eventespresso / event-espresso-core

core/db_classes/EE_Line_Item.class.php

Indentation +1659 added lines, -1659 removed lines

@@ -15,1663 +15,1663 @@
  */
 class EE_Line_Item extends EE_Base_Class implements EEI_Line_Item
 {
-    /**
-     * for children line items (currently not a normal relation)
-     *
-     * @type EE_Line_Item[]
-     */
-    protected $_children = array();
-
-    /**
-     * for the parent line item
-     *
-     * @var EE_Line_Item
-     */
-    protected $_parent;
-
-    /**
-     * @var LineItemCalculator
-     */
-    protected $calculator;
-
-
-    /**
-     * @param array  $props_n_values          incoming values
-     * @param string $timezone                incoming timezone (if not set the timezone set for the website will be
-     *                                        used.)
-     * @param array  $date_formats            incoming date_formats in an array where the first value is the
-     *                                        date_format and the second value is the time format
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function new_instance($props_n_values = array(), $timezone = null, $date_formats = array())
-    {
-        $has_object = parent::_check_for_object(
-            $props_n_values,
-            __CLASS__,
-            $timezone,
-            $date_formats
-        );
-        return $has_object
-            ? $has_object
-            : new self($props_n_values, false, $timezone);
-    }
-
-
-    /**
-     * @param array  $props_n_values  incoming values from the database
-     * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
-     *                                the website will be used.
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function new_instance_from_db($props_n_values = array(), $timezone = null)
-    {
-        return new self($props_n_values, true, $timezone);
-    }
-
-
-    /**
-     * Adds some defaults if they're not specified
-     *
-     * @param array  $fieldValues
-     * @param bool   $bydb
-     * @param string $timezone
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function __construct($fieldValues = array(), $bydb = false, $timezone = '')
-    {
-        $this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
-        parent::__construct($fieldValues, $bydb, $timezone);
-        if (! $this->get('LIN_code')) {
-            $this->set_code($this->generate_code());
-        }
-    }
-
-
-    public function __wakeup()
-    {
-        $this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
-        parent::__wakeup();
-    }
-
-
-    /**
-     * Gets ID
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ID()
-    {
-        return $this->get('LIN_ID');
-    }
-
-
-    /**
-     * Gets TXN_ID
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function TXN_ID()
-    {
-        return $this->get('TXN_ID');
-    }
-
-
-    /**
-     * Sets TXN_ID
-     *
-     * @param int $TXN_ID
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_TXN_ID($TXN_ID)
-    {
-        $this->set('TXN_ID', $TXN_ID);
-    }
-
-
-    /**
-     * Gets name
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function name()
-    {
-        $name = $this->get('LIN_name');
-        if (! $name) {
-            $name = ucwords(str_replace('-', ' ', $this->type()));
-        }
-        return $name;
-    }
-
-
-    /**
-     * Sets name
-     *
-     * @param string $name
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_name($name)
-    {
-        $this->set('LIN_name', $name);
-    }
-
-
-    /**
-     * Gets desc
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function desc()
-    {
-        return $this->get('LIN_desc');
-    }
-
-
-    /**
-     * Sets desc
-     *
-     * @param string $desc
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_desc($desc)
-    {
-        $this->set('LIN_desc', $desc);
-    }
-
-
-    /**
-     * Gets quantity
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function quantity(): int
-    {
-        return (int) $this->get('LIN_quantity');
-    }
-
-
-    /**
-     * Sets quantity
-     *
-     * @param int $quantity
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_quantity($quantity)
-    {
-        $this->set('LIN_quantity', max($quantity, 0));
-    }
-
-
-    /**
-     * Gets item_id
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function OBJ_ID()
-    {
-        return $this->get('OBJ_ID');
-    }
-
-
-    /**
-     * Sets item_id
-     *
-     * @param int $item_id
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_OBJ_ID($item_id)
-    {
-        $this->set('OBJ_ID', $item_id);
-    }
-
-
-    /**
-     * Gets item_type
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function OBJ_type()
-    {
-        return $this->get('OBJ_type');
-    }
-
-
-    /**
-     * Gets item_type
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function OBJ_type_i18n()
-    {
-        $obj_type = $this->OBJ_type();
-        switch ($obj_type) {
-            case EEM_Line_Item::OBJ_TYPE_EVENT:
-                $obj_type = esc_html__('Event', 'event_espresso');
-                break;
-            case EEM_Line_Item::OBJ_TYPE_PRICE:
-                $obj_type = esc_html__('Price', 'event_espresso');
-                break;
-            case EEM_Line_Item::OBJ_TYPE_PROMOTION:
-                $obj_type = esc_html__('Promotion', 'event_espresso');
-                break;
-            case EEM_Line_Item::OBJ_TYPE_TICKET:
-                $obj_type = esc_html__('Ticket', 'event_espresso');
-                break;
-            case EEM_Line_Item::OBJ_TYPE_TRANSACTION:
-                $obj_type = esc_html__('Transaction', 'event_espresso');
-                break;
-        }
-        return apply_filters('FHEE__EE_Line_Item__OBJ_type_i18n', $obj_type, $this);
-    }
-
-
-    /**
-     * Sets item_type
-     *
-     * @param string $OBJ_type
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_OBJ_type($OBJ_type)
-    {
-        $this->set('OBJ_type', $OBJ_type);
-    }
-
-
-    /**
-     * Gets unit_price
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function unit_price()
-    {
-        return $this->get('LIN_unit_price');
-    }
-
-
-    /**
-     * Sets unit_price
-     *
-     * @param float $unit_price
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_unit_price($unit_price)
-    {
-        $this->set('LIN_unit_price', $unit_price);
-    }
-
-
-    /**
-     * Checks if this item is a percentage modifier or not
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_percent()
-    {
-        if ($this->is_tax_sub_total()) {
-            // tax subtotals HAVE a percent on them, that percentage only applies
-            // to taxable items, so its' an exception. Treat it like a flat line item
-            return false;
-        }
-        $unit_price = abs($this->get('LIN_unit_price'));
-        $percent = abs($this->get('LIN_percent'));
-        if ($unit_price < .001 && $percent) {
-            return true;
-        }
-        if ($unit_price >= .001 && ! $percent) {
-            return false;
-        }
-        if ($unit_price >= .001 && $percent) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'A Line Item can not have a unit price of (%s) AND a percent (%s)!',
-                        'event_espresso'
-                    ),
-                    $unit_price,
-                    $percent
-                )
-            );
-        }
-        // if they're both 0, assume its not a percent item
-        return false;
-    }
-
-
-    /**
-     * Gets percent (between 100-.001)
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function percent()
-    {
-        return $this->get('LIN_percent');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since $VID:$
-     */
-    public function prettyPercent(): string
-    {
-        return $this->get_pretty('LIN_percent');
-    }
-
-
-    /**
-     * Sets percent (between 100-0.01)
-     *
-     * @param float $percent
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_percent($percent)
-    {
-        $this->set('LIN_percent', $percent);
-    }
-
-
-    /**
-     * Gets total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretaxTotal(): float
-    {
-        return (float) $this->get('LIN_pretax');
-    }
-
-
-    /**
-     * Sets total
-     *
-     * @param float $pretax_total
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function setPretaxTotal(float $pretax_total)
-    {
-        $this->set('LIN_pretax', $pretax_total);
-    }
-
-
-    /**
-     * @return float
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since  $VID:$
-     */
-    public function totalWithTax(): float
-    {
-        return (float) $this->get('LIN_total');
-    }
-
-
-    /**
-     * Sets total
-     *
-     * @param float $total
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since  $VID:$
-     */
-    public function setTotalWithTax(float $total)
-    {
-        $this->set('LIN_total', $total);
-    }
-
-
-    /**
-     * Gets total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecatd $VID:$
-     */
-    public function total(): float
-    {
-        return $this->totalWithTax();
-    }
-
-
-    /**
-     * Sets total
-     *
-     * @param float $total
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecatd $VID:$
-     */
-    public function set_total($total)
-    {
-        $this->setTotalWithTax($total);
-    }
-
-
-    /**
-     * Gets order
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function order()
-    {
-        return $this->get('LIN_order');
-    }
-
-
-    /**
-     * Sets order
-     *
-     * @param int $order
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_order($order)
-    {
-        $this->set('LIN_order', $order);
-    }
-
-
-    /**
-     * Gets parent
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function parent_ID()
-    {
-        return $this->get('LIN_parent');
-    }
-
-
-    /**
-     * Sets parent
-     *
-     * @param int $parent
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_parent_ID($parent)
-    {
-        $this->set('LIN_parent', $parent);
-    }
-
-
-    /**
-     * Gets type
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function type()
-    {
-        return $this->get('LIN_type');
-    }
-
-
-    /**
-     * Sets type
-     *
-     * @param string $type
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_type($type)
-    {
-        $this->set('LIN_type', $type);
-    }
-
-
-    /**
-     * Gets the line item of which this item is a composite. Eg, if this is a subtotal, the parent might be a total\
-     * If this line item is saved to the DB, fetches the parent from the DB. However, if this line item isn't in the DB
-     * it uses its cached reference to its parent line item (which would have been set by `EE_Line_Item::set_parent()`
-     * or indirectly by `EE_Line_item::add_child_line_item()`)
-     *
-     * @return EE_Base_Class|EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function parent()
-    {
-        return $this->ID()
-            ? $this->get_model()->get_one_by_ID($this->parent_ID())
-            : $this->_parent;
-    }
-
-
-    /**
-     * Gets ALL the children of this line item (ie, all the parts that contribute towards this total).
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function children(array $query_params = []): array
-    {
-        if ($this->ID()) {
-            // ensure where params are an array
-            $query_params[0] = $query_params[0] ?? [];
-            // add defaults for line item parent and orderby
-            $query_params[0] += ['LIN_parent' => $this->ID()];
-            $query_params += ['order_by' => ['LIN_order' => 'ASC']];
-            return $this->get_model()->get_all($query_params);
-        }
-        if (! is_array($this->_children)) {
-            $this->_children = array();
-        }
-        return $this->_children;
-    }
-
-
-    /**
-     * Gets code
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function code()
-    {
-        return $this->get('LIN_code');
-    }
-
-
-    /**
-     * Sets code
-     *
-     * @param string $code
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_code($code)
-    {
-        $this->set('LIN_code', $code);
-    }
-
-
-    /**
-     * Gets is_taxable
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_taxable()
-    {
-        return $this->get('LIN_is_taxable');
-    }
-
-
-    /**
-     * Sets is_taxable
-     *
-     * @param boolean $is_taxable
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_is_taxable($is_taxable)
-    {
-        $this->set('LIN_is_taxable', $is_taxable);
-    }
-
-
-    /**
-     * @param int $timestamp
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since $VID:$
-     */
-    public function setTimestamp(int $timestamp)
-    {
-        $this->set('LIN_timestamp', $timestamp);
-    }
-
-
-    /**
-     * Gets the object that this model-joins-to.
-     * returns one of the model objects that the field OBJ_ID can point to... see the 'OBJ_ID' field on
-     * EEM_Promotion_Object
-     *        Eg, if this line item join model object is for a ticket, this will return the EE_Ticket object
-     *
-     * @return EE_Base_Class | NULL
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_object()
-    {
-        $model_name_of_related_obj = $this->OBJ_type();
-        return $this->get_model()->has_relation($model_name_of_related_obj)
-            ? $this->get_first_related($model_name_of_related_obj)
-            : null;
-    }
-
-
-    /**
-     * Like EE_Line_Item::get_object(), but can only ever actually return an EE_Ticket.
-     * (IE, if this line item is for a price or something else, will return NULL)
-     *
-     * @param array $query_params
-     * @return EE_Base_Class|EE_Ticket
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket($query_params = array())
-    {
-        // we're going to assume that when this method is called
-        // we always want to receive the attached ticket EVEN if that ticket is archived.
-        // This can be overridden via the incoming $query_params argument
-        $remove_defaults = array('default_where_conditions' => 'none');
-        $query_params = array_merge($remove_defaults, $query_params);
-        return $this->get_first_related(EEM_Line_Item::OBJ_TYPE_TICKET, $query_params);
-    }
-
-
-    /**
-     * Gets the EE_Datetime that's related to the ticket, IF this is for a ticket
-     *
-     * @return EE_Datetime | NULL
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_ticket_datetime()
-    {
-        if ($this->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET) {
-            $ticket = $this->ticket();
-            if ($ticket instanceof EE_Ticket) {
-                $datetime = $ticket->first_datetime();
-                if ($datetime instanceof EE_Datetime) {
-                    return $datetime;
-                }
-            }
-        }
-        return null;
-    }
-
-
-    /**
-     * Gets the event's name that's related to the ticket, if this is for
-     * a ticket
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket_event_name()
-    {
-        $event_name = esc_html__('Unknown', 'event_espresso');
-        $event = $this->ticket_event();
-        if ($event instanceof EE_Event) {
-            $event_name = $event->name();
-        }
-        return $event_name;
-    }
-
-
-    /**
-     * Gets the event that's related to the ticket, if this line item represents a ticket.
-     *
-     * @return EE_Event|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket_event()
-    {
-        $event = null;
-        $ticket = $this->ticket();
-        if ($ticket instanceof EE_Ticket) {
-            $datetime = $ticket->first_datetime();
-            if ($datetime instanceof EE_Datetime) {
-                $event = $datetime->event();
-            }
-        }
-        return $event;
-    }
-
-
-    /**
-     * Gets the first datetime for this lien item, assuming it's for a ticket
-     *
-     * @param string $date_format
-     * @param string $time_format
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket_datetime_start($date_format = '', $time_format = '')
-    {
-        $first_datetime_string = esc_html__('Unknown', 'event_espresso');
-        $datetime = $this->get_ticket_datetime();
-        if ($datetime) {
-            $first_datetime_string = $datetime->start_date_and_time($date_format, $time_format);
-        }
-        return $first_datetime_string;
-    }
-
-
-    /**
-     * Adds the line item as a child to this line item. If there is another child line
-     * item with the same LIN_code, it is overwritten by this new one
-     *
-     * @param EE_Line_Item $line_item
-     * @param bool          $set_order
-     * @return bool success
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function add_child_line_item(EE_Line_Item $line_item, $set_order = true)
-    {
-        // should we calculate the LIN_order for this line item ?
-        if ($set_order || $line_item->order() === null) {
-            $line_item->set_order(count($this->children()));
-        }
-        if ($this->ID()) {
-            // check for any duplicate line items (with the same code), if so, this replaces it
-            $line_item_with_same_code = $this->get_child_line_item($line_item->code());
-            if ($line_item_with_same_code instanceof EE_Line_Item && $line_item_with_same_code !== $line_item) {
-                $this->delete_child_line_item($line_item_with_same_code->code());
-            }
-            $line_item->set_parent_ID($this->ID());
-            if ($this->TXN_ID()) {
-                $line_item->set_TXN_ID($this->TXN_ID());
-            }
-            return $line_item->save();
-        }
-        $this->_children[ $line_item->code() ] = $line_item;
-        if ($line_item->parent() !== $this) {
-            $line_item->set_parent($this);
-        }
-        return true;
-    }
-
-
-    /**
-     * Similar to EE_Base_Class::_add_relation_to, except this isn't a normal relation.
-     * If this line item is saved to the DB, this is just a wrapper for set_parent_ID() and save()
-     * However, if this line item is NOT saved to the DB, this just caches the parent on
-     * the EE_Line_Item::_parent property.
-     *
-     * @param EE_Line_Item $line_item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_parent($line_item)
-    {
-        if ($this->ID()) {
-            if (! $line_item->ID()) {
-                $line_item->save();
-            }
-            $this->set_parent_ID($line_item->ID());
-            $this->save();
-        } else {
-            $this->_parent = $line_item;
-            $this->set_parent_ID($line_item->ID());
-        }
-    }
-
-
-    /**
-     * Gets the child line item as specified by its code. Because this returns an object (by reference)
-     * you can modify this child line item and the parent (this object) can know about them
-     * because it also has a reference to that line item
-     *
-     * @param string $code
-     * @return EE_Base_Class|EE_Line_Item|EE_Soft_Delete_Base_Class|NULL
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_child_line_item($code)
-    {
-        if ($this->ID()) {
-            return $this->get_model()->get_one(
-                array(array('LIN_parent' => $this->ID(), 'LIN_code' => $code))
-            );
-        }
-        return isset($this->_children[ $code ])
-            ? $this->_children[ $code ]
-            : null;
-    }
-
-
-    /**
-     * Returns how many items are deleted (or, if this item has not been saved ot the DB yet, just how many it HAD
-     * cached on it)
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function delete_children_line_items()
-    {
-        if ($this->ID()) {
-            return $this->get_model()->delete(array(array('LIN_parent' => $this->ID())));
-        }
-        $count = count($this->_children);
-        $this->_children = array();
-        return $count;
-    }
-
-
-    /**
-     * If this line item has been saved to the DB, deletes its child with LIN_code == $code. If this line
-     * HAS NOT been saved to the DB, removes the child line item with index $code.
-     * Also searches through the child's children for a matching line item. However, once a line item has been found
-     * and deleted, stops searching (so if there are line items with duplicate codes, only the first one found will be
-     * deleted)
-     *
-     * @param string $code
-     * @param bool   $stop_search_once_found
-     * @return int count of items deleted (or simply removed from the line item's cache, if not has not been saved to
-     *             the DB yet)
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function delete_child_line_item($code, $stop_search_once_found = true)
-    {
-        if ($this->ID()) {
-            $items_deleted = 0;
-            if ($this->code() === $code) {
-                $items_deleted += EEH_Line_Item::delete_all_child_items($this);
-                $items_deleted += (int) $this->delete();
-                if ($stop_search_once_found) {
-                    return $items_deleted;
-                }
-            }
-            foreach ($this->children() as $child_line_item) {
-                $items_deleted += $child_line_item->delete_child_line_item($code, $stop_search_once_found);
-            }
-            return $items_deleted;
-        }
-        if (isset($this->_children[ $code ])) {
-            unset($this->_children[ $code ]);
-            return 1;
-        }
-        return 0;
-    }
-
-
-    /**
-     * If this line item is in the database, is of the type subtotal, and
-     * has no children, why do we have it? It should be deleted so this function
-     * does that
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function delete_if_childless_subtotal()
-    {
-        if ($this->ID() && $this->type() === EEM_Line_Item::type_sub_total && ! $this->children()) {
-            return $this->delete();
-        }
-        return false;
-    }
-
-
-    /**
-     * Creates a code and returns a string. doesn't assign the code to this model object
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function generate_code()
-    {
-        // each line item in the cart requires a unique identifier
-        return md5($this->get('OBJ_type') . $this->get('OBJ_ID') . microtime());
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function isGlobalTax(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_tax;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function isSubTax(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_sub_tax;
-    }
-
-
-    /**
-     * returns true if this is a line item with a direct descendent of the type sub-tax
-     *
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function getSubTaxes(): array
-    {
-        if (! $this->is_line_item()) {
-            return [];
-        }
-        return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_sub_tax);
-    }
-
-
-    /**
-     * returns true if this is a line item with a direct descendent of the type sub-tax
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function hasSubTaxes(): bool
-    {
-        if (! $this->is_line_item()) {
-            return false;
-        }
-        $sub_taxes = $this->getSubTaxes();
-        return ! empty($sub_taxes);
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecated   $VID:$
-     */
-    public function is_tax(): bool
-    {
-        return $this->isGlobalTax();
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_tax_sub_total()
-    {
-        return $this->type() === EEM_Line_Item::type_tax_sub_total;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_line_item()
-    {
-        return $this->type() === EEM_Line_Item::type_line_item;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_sub_line_item()
-    {
-        return $this->type() === EEM_Line_Item::type_sub_line_item;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_sub_total()
-    {
-        return $this->type() === EEM_Line_Item::type_sub_total;
-    }
-
-
-    /**
-     * Whether or not this line item is a cancellation line item
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_cancellation()
-    {
-        return EEM_Line_Item::type_cancellation === $this->type();
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_total()
-    {
-        return $this->type() === EEM_Line_Item::type_total;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_cancelled()
-    {
-        return $this->type() === EEM_Line_Item::type_cancellation;
-    }
-
-
-    /**
-     * @return string like '2, 004.00', formatted according to the localized currency
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function unit_price_no_code(): string
-    {
-        return $this->prettyUnitPrice();
-    }
-
-
-    /**
-     * @return string like '2, 004.00', formatted according to the localized currency
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since $VID:$
-     */
-    public function prettyUnitPrice(): string
-    {
-        return $this->get_pretty('LIN_unit_price', 'no_currency_code');
-    }
-
-
-    /**
-     * @return string like '2, 004.00', formatted according to the localized currency
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function total_no_code(): string
-    {
-        return $this->prettyTotal();
-    }
-
-
-    /**
-     * @return string like '2, 004.00', formatted according to the localized currency
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since $VID:$
-     */
-    public function prettyTotal(): string
-    {
-        return $this->get_pretty('LIN_total', 'no_currency_code');
-    }
-
-
-    /**
-     * Gets the final total on this item, taking taxes into account.
-     * Has the side-effect of setting the sub-total as it was just calculated.
-     * If this is used on a grand-total line item, also updates the transaction's
-     * TXN_total (provided this line item is allowed to persist, otherwise we don't
-     * want to change a persistable transaction with info from a non-persistent line item)
-     *
-     * @param bool $update_txn_status
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    public function recalculate_total_including_taxes(bool $update_txn_status = false): float
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
-        return $this->calculator->recalculateTotalIncludingTaxes($grand_total_line_item, $update_txn_status);
-    }
-
-
-    /**
-     * Recursively goes through all the children and recalculates sub-totals EXCEPT for
-     * tax-sub-totals (they're a an odd beast). Updates the 'total' on each line item according to either its
-     * unit price * quantity or the total of all its children EXCEPT when we're only calculating the taxable total and
-     * when this is called on the grand total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function recalculate_pre_tax_total(): float
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
-        [$total] = $this->calculator->recalculateLineItemTotals($grand_total_line_item);
-        return (float) $total;
-    }
-
-
-    /**
-     * Recalculates the total on each individual tax (based on a recalculation of the pre-tax total), sets
-     * the totals on each tax calculated, and returns the final tax total. Re-saves tax line items
-     * and tax sub-total if already in the DB
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function recalculate_taxes_and_tax_total(): float
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
-        return $this->calculator->recalculateTaxesAndTaxTotal($grand_total_line_item);
-    }
-
-
-    /**
-     * Gets the total tax on this line item. Assumes taxes have already been calculated using
-     * recalculate_taxes_and_total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_total_tax()
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
-        return $this->calculator->recalculateTaxesAndTaxTotal($grand_total_line_item);
-    }
-
-
-    /**
-     * Gets the total for all the items purchased only
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_items_total()
-    {
-        // by default, let's make sure we're consistent with the existing line item
-        if ($this->is_total()) {
-            return $this->pretaxTotal();
-        }
-        $total = 0;
-        foreach ($this->get_items() as $item) {
-            if ($item instanceof EE_Line_Item) {
-                $total += $item->pretaxTotal();
-            }
-        }
-        return $total;
-    }
-
-
-    /**
-     * Gets all the descendants (ie, children or children of children etc) that
-     * are of the type 'tax'
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public function tax_descendants()
-    {
-        return EEH_Line_Item::get_tax_descendants($this);
-    }
-
-
-    /**
-     * Gets all the real items purchased which are children of this item
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public function get_items()
-    {
-        return EEH_Line_Item::get_line_item_descendants($this);
-    }
-
-
-    /**
-     * Returns the amount taxable among this line item's children (or if it has no children,
-     * how much of it is taxable). Does not recalculate totals or subtotals.
-     * If the taxable total is negative, (eg, if none of the tickets were taxable,
-     * but there is a "Taxable" discount), returns 0.
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function taxable_total(): float
-    {
-        return $this->calculator->taxableAmountForGlobalTaxes($this);
-    }
-
-
-    /**
-     * Gets the transaction for this line item
-     *
-     * @return EE_Base_Class|EE_Transaction
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function transaction()
-    {
-        return $this->get_first_related(EEM_Line_Item::OBJ_TYPE_TRANSACTION);
-    }
-
-
-    /**
-     * Saves this line item to the DB, and recursively saves its descendants.
-     * Because there currently is no proper parent-child relation on the model,
-     * save_this_and_cached() will NOT save the descendants.
-     * Also sets the transaction on this line item and all its descendants before saving
-     *
-     * @param int $txn_id if none is provided, assumes $this->TXN_ID()
-     * @return int count of items saved
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function save_this_and_descendants_to_txn($txn_id = null)
-    {
-        $count = 0;
-        if (! $txn_id) {
-            $txn_id = $this->TXN_ID();
-        }
-        $this->set_TXN_ID($txn_id);
-        $children = $this->children();
-        $count += $this->save()
-            ? 1
-            : 0;
-        foreach ($children as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item) {
-                $child_line_item->set_parent_ID($this->ID());
-                $count += $child_line_item->save_this_and_descendants_to_txn($txn_id);
-            }
-        }
-        return $count;
-    }
-
-
-    /**
-     * Saves this line item to the DB, and recursively saves its descendants.
-     *
-     * @return int count of items saved
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function save_this_and_descendants()
-    {
-        $count = 0;
-        $children = $this->children();
-        $count += $this->save()
-            ? 1
-            : 0;
-        foreach ($children as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item) {
-                $child_line_item->set_parent_ID($this->ID());
-                $count += $child_line_item->save_this_and_descendants();
-            }
-        }
-        return $count;
-    }
-
-
-    /**
-     * returns the cancellation line item if this item was cancelled
-     *
-     * @return EE_Line_Item[]
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws ReflectionException
-     * @throws EE_Error
-     */
-    public function get_cancellations()
-    {
-        return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_cancellation);
-    }
-
-
-    /**
-     * If this item has an ID, then this saves it again to update the db
-     *
-     * @return int count of items saved
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function maybe_save()
-    {
-        if ($this->ID()) {
-            return $this->save();
-        }
-        return false;
-    }
-
-
-    /**
-     * clears the cached children and parent from the line item
-     *
-     * @return void
-     */
-    public function clear_related_line_item_cache()
-    {
-        $this->_children = array();
-        $this->_parent = null;
-    }
-
-
-    /**
-     * @param bool $raw
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function timestamp($raw = false)
-    {
-        return $raw
-            ? $this->get_raw('LIN_timestamp')
-            : $this->get('LIN_timestamp');
-    }
-
-
-
-
-    /************************* DEPRECATED *************************/
-    /**
-     * @deprecated 4.6.0
-     * @param string $type one of the constants on EEM_Line_Item
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    protected function _get_descendants_of_type($type)
-    {
-        EE_Error::doing_it_wrong(
-            'EE_Line_Item::_get_descendants_of_type()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::get_descendants_of_type()'
-            ),
-            '4.6.0'
-        );
-        return EEH_Line_Item::get_descendants_of_type($this, $type);
-    }
-
-
-    /**
-     * @deprecated 4.6.0
-     * @param string $type like one of the EEM_Line_Item::type_*
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_nearest_descendant_of_type(string $type): EE_Line_Item
-    {
-        EE_Error::doing_it_wrong(
-            'EE_Line_Item::get_nearest_descendant_of_type()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::get_nearest_descendant_of_type()'
-            ),
-            '4.6.0'
-        );
-        return EEH_Line_Item::get_nearest_descendant_of_type($this, $type);
-    }
+	/**
+	 * for children line items (currently not a normal relation)
+	 *
+	 * @type EE_Line_Item[]
+	 */
+	protected $_children = array();
+
+	/**
+	 * for the parent line item
+	 *
+	 * @var EE_Line_Item
+	 */
+	protected $_parent;
+
+	/**
+	 * @var LineItemCalculator
+	 */
+	protected $calculator;
+
+
+	/**
+	 * @param array  $props_n_values          incoming values
+	 * @param string $timezone                incoming timezone (if not set the timezone set for the website will be
+	 *                                        used.)
+	 * @param array  $date_formats            incoming date_formats in an array where the first value is the
+	 *                                        date_format and the second value is the time format
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function new_instance($props_n_values = array(), $timezone = null, $date_formats = array())
+	{
+		$has_object = parent::_check_for_object(
+			$props_n_values,
+			__CLASS__,
+			$timezone,
+			$date_formats
+		);
+		return $has_object
+			? $has_object
+			: new self($props_n_values, false, $timezone);
+	}
+
+
+	/**
+	 * @param array  $props_n_values  incoming values from the database
+	 * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
+	 *                                the website will be used.
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function new_instance_from_db($props_n_values = array(), $timezone = null)
+	{
+		return new self($props_n_values, true, $timezone);
+	}
+
+
+	/**
+	 * Adds some defaults if they're not specified
+	 *
+	 * @param array  $fieldValues
+	 * @param bool   $bydb
+	 * @param string $timezone
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function __construct($fieldValues = array(), $bydb = false, $timezone = '')
+	{
+		$this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
+		parent::__construct($fieldValues, $bydb, $timezone);
+		if (! $this->get('LIN_code')) {
+			$this->set_code($this->generate_code());
+		}
+	}
+
+
+	public function __wakeup()
+	{
+		$this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
+		parent::__wakeup();
+	}
+
+
+	/**
+	 * Gets ID
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ID()
+	{
+		return $this->get('LIN_ID');
+	}
+
+
+	/**
+	 * Gets TXN_ID
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function TXN_ID()
+	{
+		return $this->get('TXN_ID');
+	}
+
+
+	/**
+	 * Sets TXN_ID
+	 *
+	 * @param int $TXN_ID
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_TXN_ID($TXN_ID)
+	{
+		$this->set('TXN_ID', $TXN_ID);
+	}
+
+
+	/**
+	 * Gets name
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function name()
+	{
+		$name = $this->get('LIN_name');
+		if (! $name) {
+			$name = ucwords(str_replace('-', ' ', $this->type()));
+		}
+		return $name;
+	}
+
+
+	/**
+	 * Sets name
+	 *
+	 * @param string $name
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_name($name)
+	{
+		$this->set('LIN_name', $name);
+	}
+
+
+	/**
+	 * Gets desc
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function desc()
+	{
+		return $this->get('LIN_desc');
+	}
+
+
+	/**
+	 * Sets desc
+	 *
+	 * @param string $desc
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_desc($desc)
+	{
+		$this->set('LIN_desc', $desc);
+	}
+
+
+	/**
+	 * Gets quantity
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function quantity(): int
+	{
+		return (int) $this->get('LIN_quantity');
+	}
+
+
+	/**
+	 * Sets quantity
+	 *
+	 * @param int $quantity
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_quantity($quantity)
+	{
+		$this->set('LIN_quantity', max($quantity, 0));
+	}
+
+
+	/**
+	 * Gets item_id
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function OBJ_ID()
+	{
+		return $this->get('OBJ_ID');
+	}
+
+
+	/**
+	 * Sets item_id
+	 *
+	 * @param int $item_id
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_OBJ_ID($item_id)
+	{
+		$this->set('OBJ_ID', $item_id);
+	}
+
+
+	/**
+	 * Gets item_type
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function OBJ_type()
+	{
+		return $this->get('OBJ_type');
+	}
+
+
+	/**
+	 * Gets item_type
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function OBJ_type_i18n()
+	{
+		$obj_type = $this->OBJ_type();
+		switch ($obj_type) {
+			case EEM_Line_Item::OBJ_TYPE_EVENT:
+				$obj_type = esc_html__('Event', 'event_espresso');
+				break;
+			case EEM_Line_Item::OBJ_TYPE_PRICE:
+				$obj_type = esc_html__('Price', 'event_espresso');
+				break;
+			case EEM_Line_Item::OBJ_TYPE_PROMOTION:
+				$obj_type = esc_html__('Promotion', 'event_espresso');
+				break;
+			case EEM_Line_Item::OBJ_TYPE_TICKET:
+				$obj_type = esc_html__('Ticket', 'event_espresso');
+				break;
+			case EEM_Line_Item::OBJ_TYPE_TRANSACTION:
+				$obj_type = esc_html__('Transaction', 'event_espresso');
+				break;
+		}
+		return apply_filters('FHEE__EE_Line_Item__OBJ_type_i18n', $obj_type, $this);
+	}
+
+
+	/**
+	 * Sets item_type
+	 *
+	 * @param string $OBJ_type
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_OBJ_type($OBJ_type)
+	{
+		$this->set('OBJ_type', $OBJ_type);
+	}
+
+
+	/**
+	 * Gets unit_price
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function unit_price()
+	{
+		return $this->get('LIN_unit_price');
+	}
+
+
+	/**
+	 * Sets unit_price
+	 *
+	 * @param float $unit_price
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_unit_price($unit_price)
+	{
+		$this->set('LIN_unit_price', $unit_price);
+	}
+
+
+	/**
+	 * Checks if this item is a percentage modifier or not
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_percent()
+	{
+		if ($this->is_tax_sub_total()) {
+			// tax subtotals HAVE a percent on them, that percentage only applies
+			// to taxable items, so its' an exception. Treat it like a flat line item
+			return false;
+		}
+		$unit_price = abs($this->get('LIN_unit_price'));
+		$percent = abs($this->get('LIN_percent'));
+		if ($unit_price < .001 && $percent) {
+			return true;
+		}
+		if ($unit_price >= .001 && ! $percent) {
+			return false;
+		}
+		if ($unit_price >= .001 && $percent) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'A Line Item can not have a unit price of (%s) AND a percent (%s)!',
+						'event_espresso'
+					),
+					$unit_price,
+					$percent
+				)
+			);
+		}
+		// if they're both 0, assume its not a percent item
+		return false;
+	}
+
+
+	/**
+	 * Gets percent (between 100-.001)
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function percent()
+	{
+		return $this->get('LIN_percent');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since $VID:$
+	 */
+	public function prettyPercent(): string
+	{
+		return $this->get_pretty('LIN_percent');
+	}
+
+
+	/**
+	 * Sets percent (between 100-0.01)
+	 *
+	 * @param float $percent
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_percent($percent)
+	{
+		$this->set('LIN_percent', $percent);
+	}
+
+
+	/**
+	 * Gets total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretaxTotal(): float
+	{
+		return (float) $this->get('LIN_pretax');
+	}
+
+
+	/**
+	 * Sets total
+	 *
+	 * @param float $pretax_total
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function setPretaxTotal(float $pretax_total)
+	{
+		$this->set('LIN_pretax', $pretax_total);
+	}
+
+
+	/**
+	 * @return float
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since  $VID:$
+	 */
+	public function totalWithTax(): float
+	{
+		return (float) $this->get('LIN_total');
+	}
+
+
+	/**
+	 * Sets total
+	 *
+	 * @param float $total
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since  $VID:$
+	 */
+	public function setTotalWithTax(float $total)
+	{
+		$this->set('LIN_total', $total);
+	}
+
+
+	/**
+	 * Gets total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecatd $VID:$
+	 */
+	public function total(): float
+	{
+		return $this->totalWithTax();
+	}
+
+
+	/**
+	 * Sets total
+	 *
+	 * @param float $total
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecatd $VID:$
+	 */
+	public function set_total($total)
+	{
+		$this->setTotalWithTax($total);
+	}
+
+
+	/**
+	 * Gets order
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function order()
+	{
+		return $this->get('LIN_order');
+	}
+
+
+	/**
+	 * Sets order
+	 *
+	 * @param int $order
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_order($order)
+	{
+		$this->set('LIN_order', $order);
+	}
+
+
+	/**
+	 * Gets parent
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function parent_ID()
+	{
+		return $this->get('LIN_parent');
+	}
+
+
+	/**
+	 * Sets parent
+	 *
+	 * @param int $parent
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_parent_ID($parent)
+	{
+		$this->set('LIN_parent', $parent);
+	}
+
+
+	/**
+	 * Gets type
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function type()
+	{
+		return $this->get('LIN_type');
+	}
+
+
+	/**
+	 * Sets type
+	 *
+	 * @param string $type
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_type($type)
+	{
+		$this->set('LIN_type', $type);
+	}
+
+
+	/**
+	 * Gets the line item of which this item is a composite. Eg, if this is a subtotal, the parent might be a total\
+	 * If this line item is saved to the DB, fetches the parent from the DB. However, if this line item isn't in the DB
+	 * it uses its cached reference to its parent line item (which would have been set by `EE_Line_Item::set_parent()`
+	 * or indirectly by `EE_Line_item::add_child_line_item()`)
+	 *
+	 * @return EE_Base_Class|EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function parent()
+	{
+		return $this->ID()
+			? $this->get_model()->get_one_by_ID($this->parent_ID())
+			: $this->_parent;
+	}
+
+
+	/**
+	 * Gets ALL the children of this line item (ie, all the parts that contribute towards this total).
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function children(array $query_params = []): array
+	{
+		if ($this->ID()) {
+			// ensure where params are an array
+			$query_params[0] = $query_params[0] ?? [];
+			// add defaults for line item parent and orderby
+			$query_params[0] += ['LIN_parent' => $this->ID()];
+			$query_params += ['order_by' => ['LIN_order' => 'ASC']];
+			return $this->get_model()->get_all($query_params);
+		}
+		if (! is_array($this->_children)) {
+			$this->_children = array();
+		}
+		return $this->_children;
+	}
+
+
+	/**
+	 * Gets code
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function code()
+	{
+		return $this->get('LIN_code');
+	}
+
+
+	/**
+	 * Sets code
+	 *
+	 * @param string $code
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_code($code)
+	{
+		$this->set('LIN_code', $code);
+	}
+
+
+	/**
+	 * Gets is_taxable
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_taxable()
+	{
+		return $this->get('LIN_is_taxable');
+	}
+
+
+	/**
+	 * Sets is_taxable
+	 *
+	 * @param boolean $is_taxable
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_is_taxable($is_taxable)
+	{
+		$this->set('LIN_is_taxable', $is_taxable);
+	}
+
+
+	/**
+	 * @param int $timestamp
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since $VID:$
+	 */
+	public function setTimestamp(int $timestamp)
+	{
+		$this->set('LIN_timestamp', $timestamp);
+	}
+
+
+	/**
+	 * Gets the object that this model-joins-to.
+	 * returns one of the model objects that the field OBJ_ID can point to... see the 'OBJ_ID' field on
+	 * EEM_Promotion_Object
+	 *        Eg, if this line item join model object is for a ticket, this will return the EE_Ticket object
+	 *
+	 * @return EE_Base_Class | NULL
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_object()
+	{
+		$model_name_of_related_obj = $this->OBJ_type();
+		return $this->get_model()->has_relation($model_name_of_related_obj)
+			? $this->get_first_related($model_name_of_related_obj)
+			: null;
+	}
+
+
+	/**
+	 * Like EE_Line_Item::get_object(), but can only ever actually return an EE_Ticket.
+	 * (IE, if this line item is for a price or something else, will return NULL)
+	 *
+	 * @param array $query_params
+	 * @return EE_Base_Class|EE_Ticket
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket($query_params = array())
+	{
+		// we're going to assume that when this method is called
+		// we always want to receive the attached ticket EVEN if that ticket is archived.
+		// This can be overridden via the incoming $query_params argument
+		$remove_defaults = array('default_where_conditions' => 'none');
+		$query_params = array_merge($remove_defaults, $query_params);
+		return $this->get_first_related(EEM_Line_Item::OBJ_TYPE_TICKET, $query_params);
+	}
+
+
+	/**
+	 * Gets the EE_Datetime that's related to the ticket, IF this is for a ticket
+	 *
+	 * @return EE_Datetime | NULL
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_ticket_datetime()
+	{
+		if ($this->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET) {
+			$ticket = $this->ticket();
+			if ($ticket instanceof EE_Ticket) {
+				$datetime = $ticket->first_datetime();
+				if ($datetime instanceof EE_Datetime) {
+					return $datetime;
+				}
+			}
+		}
+		return null;
+	}
+
+
+	/**
+	 * Gets the event's name that's related to the ticket, if this is for
+	 * a ticket
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket_event_name()
+	{
+		$event_name = esc_html__('Unknown', 'event_espresso');
+		$event = $this->ticket_event();
+		if ($event instanceof EE_Event) {
+			$event_name = $event->name();
+		}
+		return $event_name;
+	}
+
+
+	/**
+	 * Gets the event that's related to the ticket, if this line item represents a ticket.
+	 *
+	 * @return EE_Event|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket_event()
+	{
+		$event = null;
+		$ticket = $this->ticket();
+		if ($ticket instanceof EE_Ticket) {
+			$datetime = $ticket->first_datetime();
+			if ($datetime instanceof EE_Datetime) {
+				$event = $datetime->event();
+			}
+		}
+		return $event;
+	}
+
+
+	/**
+	 * Gets the first datetime for this lien item, assuming it's for a ticket
+	 *
+	 * @param string $date_format
+	 * @param string $time_format
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket_datetime_start($date_format = '', $time_format = '')
+	{
+		$first_datetime_string = esc_html__('Unknown', 'event_espresso');
+		$datetime = $this->get_ticket_datetime();
+		if ($datetime) {
+			$first_datetime_string = $datetime->start_date_and_time($date_format, $time_format);
+		}
+		return $first_datetime_string;
+	}
+
+
+	/**
+	 * Adds the line item as a child to this line item. If there is another child line
+	 * item with the same LIN_code, it is overwritten by this new one
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @param bool          $set_order
+	 * @return bool success
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function add_child_line_item(EE_Line_Item $line_item, $set_order = true)
+	{
+		// should we calculate the LIN_order for this line item ?
+		if ($set_order || $line_item->order() === null) {
+			$line_item->set_order(count($this->children()));
+		}
+		if ($this->ID()) {
+			// check for any duplicate line items (with the same code), if so, this replaces it
+			$line_item_with_same_code = $this->get_child_line_item($line_item->code());
+			if ($line_item_with_same_code instanceof EE_Line_Item && $line_item_with_same_code !== $line_item) {
+				$this->delete_child_line_item($line_item_with_same_code->code());
+			}
+			$line_item->set_parent_ID($this->ID());
+			if ($this->TXN_ID()) {
+				$line_item->set_TXN_ID($this->TXN_ID());
+			}
+			return $line_item->save();
+		}
+		$this->_children[ $line_item->code() ] = $line_item;
+		if ($line_item->parent() !== $this) {
+			$line_item->set_parent($this);
+		}
+		return true;
+	}
+
+
+	/**
+	 * Similar to EE_Base_Class::_add_relation_to, except this isn't a normal relation.
+	 * If this line item is saved to the DB, this is just a wrapper for set_parent_ID() and save()
+	 * However, if this line item is NOT saved to the DB, this just caches the parent on
+	 * the EE_Line_Item::_parent property.
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_parent($line_item)
+	{
+		if ($this->ID()) {
+			if (! $line_item->ID()) {
+				$line_item->save();
+			}
+			$this->set_parent_ID($line_item->ID());
+			$this->save();
+		} else {
+			$this->_parent = $line_item;
+			$this->set_parent_ID($line_item->ID());
+		}
+	}
+
+
+	/**
+	 * Gets the child line item as specified by its code. Because this returns an object (by reference)
+	 * you can modify this child line item and the parent (this object) can know about them
+	 * because it also has a reference to that line item
+	 *
+	 * @param string $code
+	 * @return EE_Base_Class|EE_Line_Item|EE_Soft_Delete_Base_Class|NULL
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_child_line_item($code)
+	{
+		if ($this->ID()) {
+			return $this->get_model()->get_one(
+				array(array('LIN_parent' => $this->ID(), 'LIN_code' => $code))
+			);
+		}
+		return isset($this->_children[ $code ])
+			? $this->_children[ $code ]
+			: null;
+	}
+
+
+	/**
+	 * Returns how many items are deleted (or, if this item has not been saved ot the DB yet, just how many it HAD
+	 * cached on it)
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function delete_children_line_items()
+	{
+		if ($this->ID()) {
+			return $this->get_model()->delete(array(array('LIN_parent' => $this->ID())));
+		}
+		$count = count($this->_children);
+		$this->_children = array();
+		return $count;
+	}
+
+
+	/**
+	 * If this line item has been saved to the DB, deletes its child with LIN_code == $code. If this line
+	 * HAS NOT been saved to the DB, removes the child line item with index $code.
+	 * Also searches through the child's children for a matching line item. However, once a line item has been found
+	 * and deleted, stops searching (so if there are line items with duplicate codes, only the first one found will be
+	 * deleted)
+	 *
+	 * @param string $code
+	 * @param bool   $stop_search_once_found
+	 * @return int count of items deleted (or simply removed from the line item's cache, if not has not been saved to
+	 *             the DB yet)
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function delete_child_line_item($code, $stop_search_once_found = true)
+	{
+		if ($this->ID()) {
+			$items_deleted = 0;
+			if ($this->code() === $code) {
+				$items_deleted += EEH_Line_Item::delete_all_child_items($this);
+				$items_deleted += (int) $this->delete();
+				if ($stop_search_once_found) {
+					return $items_deleted;
+				}
+			}
+			foreach ($this->children() as $child_line_item) {
+				$items_deleted += $child_line_item->delete_child_line_item($code, $stop_search_once_found);
+			}
+			return $items_deleted;
+		}
+		if (isset($this->_children[ $code ])) {
+			unset($this->_children[ $code ]);
+			return 1;
+		}
+		return 0;
+	}
+
+
+	/**
+	 * If this line item is in the database, is of the type subtotal, and
+	 * has no children, why do we have it? It should be deleted so this function
+	 * does that
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function delete_if_childless_subtotal()
+	{
+		if ($this->ID() && $this->type() === EEM_Line_Item::type_sub_total && ! $this->children()) {
+			return $this->delete();
+		}
+		return false;
+	}
+
+
+	/**
+	 * Creates a code and returns a string. doesn't assign the code to this model object
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function generate_code()
+	{
+		// each line item in the cart requires a unique identifier
+		return md5($this->get('OBJ_type') . $this->get('OBJ_ID') . microtime());
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function isGlobalTax(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_tax;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function isSubTax(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_sub_tax;
+	}
+
+
+	/**
+	 * returns true if this is a line item with a direct descendent of the type sub-tax
+	 *
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function getSubTaxes(): array
+	{
+		if (! $this->is_line_item()) {
+			return [];
+		}
+		return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_sub_tax);
+	}
+
+
+	/**
+	 * returns true if this is a line item with a direct descendent of the type sub-tax
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function hasSubTaxes(): bool
+	{
+		if (! $this->is_line_item()) {
+			return false;
+		}
+		$sub_taxes = $this->getSubTaxes();
+		return ! empty($sub_taxes);
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecated   $VID:$
+	 */
+	public function is_tax(): bool
+	{
+		return $this->isGlobalTax();
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_tax_sub_total()
+	{
+		return $this->type() === EEM_Line_Item::type_tax_sub_total;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_line_item()
+	{
+		return $this->type() === EEM_Line_Item::type_line_item;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_sub_line_item()
+	{
+		return $this->type() === EEM_Line_Item::type_sub_line_item;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_sub_total()
+	{
+		return $this->type() === EEM_Line_Item::type_sub_total;
+	}
+
+
+	/**
+	 * Whether or not this line item is a cancellation line item
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_cancellation()
+	{
+		return EEM_Line_Item::type_cancellation === $this->type();
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_total()
+	{
+		return $this->type() === EEM_Line_Item::type_total;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_cancelled()
+	{
+		return $this->type() === EEM_Line_Item::type_cancellation;
+	}
+
+
+	/**
+	 * @return string like '2, 004.00', formatted according to the localized currency
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function unit_price_no_code(): string
+	{
+		return $this->prettyUnitPrice();
+	}
+
+
+	/**
+	 * @return string like '2, 004.00', formatted according to the localized currency
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since $VID:$
+	 */
+	public function prettyUnitPrice(): string
+	{
+		return $this->get_pretty('LIN_unit_price', 'no_currency_code');
+	}
+
+
+	/**
+	 * @return string like '2, 004.00', formatted according to the localized currency
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function total_no_code(): string
+	{
+		return $this->prettyTotal();
+	}
+
+
+	/**
+	 * @return string like '2, 004.00', formatted according to the localized currency
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since $VID:$
+	 */
+	public function prettyTotal(): string
+	{
+		return $this->get_pretty('LIN_total', 'no_currency_code');
+	}
+
+
+	/**
+	 * Gets the final total on this item, taking taxes into account.
+	 * Has the side-effect of setting the sub-total as it was just calculated.
+	 * If this is used on a grand-total line item, also updates the transaction's
+	 * TXN_total (provided this line item is allowed to persist, otherwise we don't
+	 * want to change a persistable transaction with info from a non-persistent line item)
+	 *
+	 * @param bool $update_txn_status
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	public function recalculate_total_including_taxes(bool $update_txn_status = false): float
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
+		return $this->calculator->recalculateTotalIncludingTaxes($grand_total_line_item, $update_txn_status);
+	}
+
+
+	/**
+	 * Recursively goes through all the children and recalculates sub-totals EXCEPT for
+	 * tax-sub-totals (they're a an odd beast). Updates the 'total' on each line item according to either its
+	 * unit price * quantity or the total of all its children EXCEPT when we're only calculating the taxable total and
+	 * when this is called on the grand total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function recalculate_pre_tax_total(): float
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
+		[$total] = $this->calculator->recalculateLineItemTotals($grand_total_line_item);
+		return (float) $total;
+	}
+
+
+	/**
+	 * Recalculates the total on each individual tax (based on a recalculation of the pre-tax total), sets
+	 * the totals on each tax calculated, and returns the final tax total. Re-saves tax line items
+	 * and tax sub-total if already in the DB
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function recalculate_taxes_and_tax_total(): float
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
+		return $this->calculator->recalculateTaxesAndTaxTotal($grand_total_line_item);
+	}
+
+
+	/**
+	 * Gets the total tax on this line item. Assumes taxes have already been calculated using
+	 * recalculate_taxes_and_total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_total_tax()
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
+		return $this->calculator->recalculateTaxesAndTaxTotal($grand_total_line_item);
+	}
+
+
+	/**
+	 * Gets the total for all the items purchased only
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_items_total()
+	{
+		// by default, let's make sure we're consistent with the existing line item
+		if ($this->is_total()) {
+			return $this->pretaxTotal();
+		}
+		$total = 0;
+		foreach ($this->get_items() as $item) {
+			if ($item instanceof EE_Line_Item) {
+				$total += $item->pretaxTotal();
+			}
+		}
+		return $total;
+	}
+
+
+	/**
+	 * Gets all the descendants (ie, children or children of children etc) that
+	 * are of the type 'tax'
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public function tax_descendants()
+	{
+		return EEH_Line_Item::get_tax_descendants($this);
+	}
+
+
+	/**
+	 * Gets all the real items purchased which are children of this item
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public function get_items()
+	{
+		return EEH_Line_Item::get_line_item_descendants($this);
+	}
+
+
+	/**
+	 * Returns the amount taxable among this line item's children (or if it has no children,
+	 * how much of it is taxable). Does not recalculate totals or subtotals.
+	 * If the taxable total is negative, (eg, if none of the tickets were taxable,
+	 * but there is a "Taxable" discount), returns 0.
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function taxable_total(): float
+	{
+		return $this->calculator->taxableAmountForGlobalTaxes($this);
+	}
+
+
+	/**
+	 * Gets the transaction for this line item
+	 *
+	 * @return EE_Base_Class|EE_Transaction
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function transaction()
+	{
+		return $this->get_first_related(EEM_Line_Item::OBJ_TYPE_TRANSACTION);
+	}
+
+
+	/**
+	 * Saves this line item to the DB, and recursively saves its descendants.
+	 * Because there currently is no proper parent-child relation on the model,
+	 * save_this_and_cached() will NOT save the descendants.
+	 * Also sets the transaction on this line item and all its descendants before saving
+	 *
+	 * @param int $txn_id if none is provided, assumes $this->TXN_ID()
+	 * @return int count of items saved
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function save_this_and_descendants_to_txn($txn_id = null)
+	{
+		$count = 0;
+		if (! $txn_id) {
+			$txn_id = $this->TXN_ID();
+		}
+		$this->set_TXN_ID($txn_id);
+		$children = $this->children();
+		$count += $this->save()
+			? 1
+			: 0;
+		foreach ($children as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item) {
+				$child_line_item->set_parent_ID($this->ID());
+				$count += $child_line_item->save_this_and_descendants_to_txn($txn_id);
+			}
+		}
+		return $count;
+	}
+
+
+	/**
+	 * Saves this line item to the DB, and recursively saves its descendants.
+	 *
+	 * @return int count of items saved
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function save_this_and_descendants()
+	{
+		$count = 0;
+		$children = $this->children();
+		$count += $this->save()
+			? 1
+			: 0;
+		foreach ($children as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item) {
+				$child_line_item->set_parent_ID($this->ID());
+				$count += $child_line_item->save_this_and_descendants();
+			}
+		}
+		return $count;
+	}
+
+
+	/**
+	 * returns the cancellation line item if this item was cancelled
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws ReflectionException
+	 * @throws EE_Error
+	 */
+	public function get_cancellations()
+	{
+		return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_cancellation);
+	}
+
+
+	/**
+	 * If this item has an ID, then this saves it again to update the db
+	 *
+	 * @return int count of items saved
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function maybe_save()
+	{
+		if ($this->ID()) {
+			return $this->save();
+		}
+		return false;
+	}
+
+
+	/**
+	 * clears the cached children and parent from the line item
+	 *
+	 * @return void
+	 */
+	public function clear_related_line_item_cache()
+	{
+		$this->_children = array();
+		$this->_parent = null;
+	}
+
+
+	/**
+	 * @param bool $raw
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function timestamp($raw = false)
+	{
+		return $raw
+			? $this->get_raw('LIN_timestamp')
+			: $this->get('LIN_timestamp');
+	}
+
+
+
+
+	/************************* DEPRECATED *************************/
+	/**
+	 * @deprecated 4.6.0
+	 * @param string $type one of the constants on EEM_Line_Item
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	protected function _get_descendants_of_type($type)
+	{
+		EE_Error::doing_it_wrong(
+			'EE_Line_Item::_get_descendants_of_type()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::get_descendants_of_type()'
+			),
+			'4.6.0'
+		);
+		return EEH_Line_Item::get_descendants_of_type($this, $type);
+	}
+
+
+	/**
+	 * @deprecated 4.6.0
+	 * @param string $type like one of the EEM_Line_Item::type_*
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_nearest_descendant_of_type(string $type): EE_Line_Item
+	{
+		EE_Error::doing_it_wrong(
+			'EE_Line_Item::get_nearest_descendant_of_type()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::get_nearest_descendant_of_type()'
+			),
+			'4.6.0'
+		);
+		return EEH_Line_Item::get_nearest_descendant_of_type($this, $type);
+	}
 }

core/helpers/EEH_Line_Item.helper.php

Indentation +2128 added lines, -2128 removed lines

@@ -21,2132 +21,2132 @@
  */
 class EEH_Line_Item
 {
-    /**
-     * @var EE_Line_Item[]
-    */
-    private static $global_taxes;
-
-
-    /**
-     * Adds a simple item (unrelated to any other model object) to the provided PARENT line item.
-     * Does NOT automatically re-calculate the line item totals or update the related transaction.
-     * You should call recalculate_total_including_taxes() on the grant total line item after this
-     * to update the subtotals, and EE_Registration_Processor::calculate_reg_final_prices_per_line_item()
-     * to keep the registration final prices in-sync with the transaction's total.
-     *
-     * @param EE_Line_Item $parent_line_item
-     * @param string       $name
-     * @param float        $unit_price
-     * @param string       $description
-     * @param int          $quantity
-     * @param boolean      $taxable
-     * @param string|null  $code if set to a value, ensures there is only one line item with that code
-     * @param bool         $return_item
-     * @param bool         $recalculate_totals
-     * @return boolean|EE_Line_Item success
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function add_unrelated_item(
-        EE_Line_Item $parent_line_item,
-        string $name,
-        float $unit_price,
-        string $description = '',
-        int $quantity = 1,
-        bool $taxable = false,
-        ?string $code = null,
-        bool $return_item = false,
-        bool $recalculate_totals = true
-    ) {
-        $items_subtotal = self::get_pre_tax_subtotal($parent_line_item);
-        $line_item      = EE_Line_Item::new_instance(
-            [
-                'LIN_name'       => $name,
-                'LIN_desc'       => $description,
-                'LIN_unit_price' => $unit_price,
-                'LIN_quantity'   => $quantity,
-                'LIN_percent'    => null,
-                'LIN_is_taxable' => $taxable,
-                'LIN_order'      => $items_subtotal instanceof EE_Line_Item
-                    ? count($items_subtotal->children())
-                    : 0,
-                'LIN_total'      => (float) $unit_price * (int) $quantity,
-                'LIN_type'       => EEM_Line_Item::type_line_item,
-                'LIN_code'       => $code,
-            ]
-        );
-        $line_item      = apply_filters(
-            'FHEE__EEH_Line_Item__add_unrelated_item__line_item',
-            $line_item,
-            $parent_line_item
-        );
-        $added          = self::add_item($parent_line_item, $line_item, $recalculate_totals);
-        return $return_item ? $line_item : $added;
-    }
-
-
-    /**
-     * Adds a simple item ( unrelated to any other model object) to the total line item,
-     * in the correct spot in the line item tree. Does not automatically
-     * re-calculate the line item totals, nor update the related transaction, nor upgrade the transaction's
-     * registrations' final prices (which should probably change because of this).
-     * You should call recalculate_total_including_taxes() on the grand total line item, then
-     * update the transaction's total, and EE_Registration_Processor::update_registration_final_prices()
-     * after using this, to keep the registration final prices in-sync with the transaction's total.
-     *
-     * @param EE_Line_Item $parent_line_item
-     * @param string       $name
-     * @param float        $percentage_amount
-     * @param string       $description
-     * @param boolean      $taxable
-     * @param string|null  $code
-     * @param bool         $return_item
-     * @return boolean|EE_Line_Item success
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function add_percentage_based_item(
-        EE_Line_Item $parent_line_item,
-        string $name,
-        float $percentage_amount,
-        string $description = '',
-        bool $taxable = false,
-        ?string $code = null,
-        bool $return_item = false
-    ) {
-        $total = $percentage_amount * $parent_line_item->total() / 100;
-        $line_item = EE_Line_Item::new_instance(
-            [
-                'LIN_name'       => $name,
-                'LIN_desc'       => $description,
-                'LIN_unit_price' => 0,
-                'LIN_percent'    => $percentage_amount,
-                'LIN_quantity'   => 1,
-                'LIN_is_taxable' => $taxable,
-                'LIN_total'      => (float) $total,
-                'LIN_type'       => EEM_Line_Item::type_line_item,
-                'LIN_parent'     => $parent_line_item->ID(),
-                'LIN_code'       => $code,
-            ]
-        );
-        $line_item = apply_filters(
-            'FHEE__EEH_Line_Item__add_percentage_based_item__line_item',
-            $line_item
-        );
-        $added     = $parent_line_item->add_child_line_item($line_item, false);
-        return $return_item ? $line_item : $added;
-    }
-
-
-    /**
-     * Returns the new line item created by adding a purchase of the ticket
-     * ensures that ticket line item is saved, and that cart total has been recalculated.
-     * If this ticket has already been purchased, just increments its count.
-     * Automatically re-calculates the line item totals and updates the related transaction. But
-     * DOES NOT automatically upgrade the transaction's registrations' final prices (which
-     * should probably change because of this).
-     * You should call EE_Registration_Processor::calculate_reg_final_prices_per_line_item()
-     * after using this, to keep the registration final prices in-sync with the transaction's total.
-     *
-     * @param EE_Line_Item|null $total_line_item grand total line item of type EEM_Line_Item::type_total
-     * @param EE_Ticket         $ticket
-     * @param int               $qty
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function add_ticket_purchase(
-        ?EE_Line_Item $total_line_item,
-        EE_Ticket $ticket,
-        int $qty = 1
-    ): ?EE_Line_Item {
-        if (! $total_line_item instanceof EE_Line_Item || ! $total_line_item->is_total()) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'A valid line item total is required in order to add tickets. A line item of type "%s" was passed.',
-                        'event_espresso'
-                    ),
-                    $ticket->ID(),
-                    $total_line_item->ID()
-                )
-            );
-        }
-        // either increment the qty for an existing ticket
-        $line_item = self::increment_ticket_qty_if_already_in_cart($total_line_item, $ticket, $qty);
-        // or add a new one
-        if (! $line_item instanceof EE_Line_Item) {
-            $line_item = self::create_ticket_line_item($total_line_item, $ticket, $qty);
-        }
-        $total_line_item->recalculate_total_including_taxes();
-        return $line_item;
-    }
-
-
-    /**
-     * Returns the new line item created by adding a purchase of the ticket
-     *
-     * @param EE_Line_Item $total_line_item
-     * @param EE_Ticket    $ticket
-     * @param int          $qty
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function increment_ticket_qty_if_already_in_cart(
-        EE_Line_Item $total_line_item,
-        EE_Ticket $ticket,
-        $qty = 1
-    ) {
-        $line_item = null;
-        if ($total_line_item instanceof EE_Line_Item && $total_line_item->is_total()) {
-            $ticket_line_items = EEH_Line_Item::get_ticket_line_items($total_line_item);
-            foreach ($ticket_line_items as $ticket_line_item) {
-                if (
-                    $ticket_line_item instanceof EE_Line_Item
-                    && (int) $ticket_line_item->OBJ_ID() === (int) $ticket->ID()
-                ) {
-                    $line_item = $ticket_line_item;
-                    break;
-                }
-            }
-        }
-        if ($line_item instanceof EE_Line_Item) {
-            EEH_Line_Item::increment_quantity($line_item, $qty);
-            return $line_item;
-        }
-        return null;
-    }
-
-
-    /**
-     * Increments the line item and all its children's quantity by $qty (but percent line items are unaffected).
-     * Does NOT save or recalculate other line items totals
-     *
-     * @param EE_Line_Item $line_item
-     * @param int          $qty
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function increment_quantity(EE_Line_Item $line_item, $qty = 1)
-    {
-        if (! $line_item->is_percent()) {
-            $qty += $line_item->quantity();
-            $line_item->set_quantity($qty);
-            $line_item->set_total($line_item->unit_price() * $qty);
-            $line_item->save();
-        }
-        foreach ($line_item->children() as $child) {
-            if ($child->is_sub_line_item()) {
-                EEH_Line_Item::update_quantity($child, $qty);
-            }
-        }
-    }
-
-
-    /**
-     * Decrements the line item and all its children's quantity by $qty (but percent line items are unaffected).
-     * Does NOT save or recalculate other line items totals
-     *
-     * @param EE_Line_Item $line_item
-     * @param int          $qty
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function decrement_quantity(EE_Line_Item $line_item, $qty = 1)
-    {
-        if (! $line_item->is_percent()) {
-            $qty = $line_item->quantity() - $qty;
-            $qty = max($qty, 0);
-            $line_item->set_quantity($qty);
-            $line_item->set_total($line_item->unit_price() * $qty);
-            $line_item->save();
-        }
-        foreach ($line_item->children() as $child) {
-            if ($child->is_sub_line_item()) {
-                EEH_Line_Item::update_quantity($child, $qty);
-            }
-        }
-    }
-
-
-    /**
-     * Updates the line item and its children's quantities to the specified number.
-     * Does NOT save them or recalculate totals.
-     *
-     * @param EE_Line_Item $line_item
-     * @param int          $new_quantity
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function update_quantity(EE_Line_Item $line_item, $new_quantity)
-    {
-        if (! $line_item->is_percent()) {
-            $line_item->set_quantity($new_quantity);
-            $line_item->set_total($line_item->unit_price() * $new_quantity);
-            $line_item->save();
-        }
-        foreach ($line_item->children() as $child) {
-            if ($child->is_sub_line_item()) {
-                EEH_Line_Item::update_quantity($child, $new_quantity);
-            }
-        }
-    }
-
-
-    /**
-     * Returns the new line item created by adding a purchase of the ticket
-     *
-     * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
-     * @param EE_Ticket    $ticket
-     * @param int          $qty
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function create_ticket_line_item(EE_Line_Item $total_line_item, EE_Ticket $ticket, $qty = 1)
-    {
-        $datetimes = $ticket->datetimes();
-        $first_datetime = reset($datetimes);
-        $first_datetime_name = esc_html__('Event', 'event_espresso');
-        if ($first_datetime instanceof EE_Datetime && $first_datetime->event() instanceof EE_Event) {
-            $first_datetime_name = $first_datetime->event()->name();
-        }
-        $event = sprintf(_x('(For %1$s)', '(For Event Name)', 'event_espresso'), $first_datetime_name);
-        // get event subtotal line
-        $events_sub_total = self::get_event_line_item_for_ticket($total_line_item, $ticket);
-        $taxes = $ticket->tax_price_modifiers();
-        // add $ticket to cart
-        $line_item = EE_Line_Item::new_instance(array(
-            'LIN_name'       => $ticket->name(),
-            'LIN_desc'       => $ticket->description() !== '' ? $ticket->description() . ' ' . $event : $event,
-            'LIN_unit_price' => $ticket->price(),
-            'LIN_quantity'   => $qty,
-            'LIN_is_taxable' => empty($taxes) && $ticket->taxable(),
-            'LIN_order'      => count($events_sub_total->children()),
-            'LIN_total'      => $ticket->price() * $qty,
-            'LIN_type'       => EEM_Line_Item::type_line_item,
-            'OBJ_ID'         => $ticket->ID(),
-            'OBJ_type'       => EEM_Line_Item::OBJ_TYPE_TICKET,
-        ));
-        $line_item = apply_filters(
-            'FHEE__EEH_Line_Item__create_ticket_line_item__line_item',
-            $line_item
-        );
-        if (!$line_item instanceof EE_Line_Item) {
-            throw new DomainException(
-                esc_html__('Invalid EE_Line_Item received.', 'event_espresso')
-            );
-        }
-        $events_sub_total->add_child_line_item($line_item);
-        // now add the sub-line items
-        $running_total = 0;
-        $running_pre_tax_total = 0;
-        foreach ($ticket->prices() as $price) {
-            $sign = $price->is_discount() ? -1 : 1;
-            $price_total = $price->is_percent()
-                ? $running_pre_tax_total * $price->amount() / 100
-                : $price->amount() * $qty;
-            if ($price->is_percent()) {
-                $percent = $sign * $price->amount();
-                $unit_price = 0;
-            } else {
-                $percent    = 0;
-                $unit_price = $sign * $price->amount();
-            }
-            $sub_line_item = EE_Line_Item::new_instance(array(
-                'LIN_name'       => $price->name(),
-                'LIN_desc'       => $price->desc(),
-                'LIN_quantity'   => $price->is_percent() ? null : $qty,
-                'LIN_is_taxable' => false,
-                'LIN_order'      => $price->order(),
-                'LIN_total'      => $price_total,
-                'LIN_pretax'     => 0,
-                'LIN_unit_price' => $unit_price,
-                'LIN_percent'    => $percent,
-                'LIN_type'       => $price->is_tax() ? EEM_Line_Item::type_sub_tax : EEM_Line_Item::type_sub_line_item,
-                'OBJ_ID'         => $price->ID(),
-                'OBJ_type'       => EEM_Line_Item::OBJ_TYPE_PRICE,
-            ));
-            $sub_line_item = apply_filters(
-                'FHEE__EEH_Line_Item__create_ticket_line_item__sub_line_item',
-                $sub_line_item
-            );
-            $running_total += $sign * $price_total;
-            $running_pre_tax_total += ! $price->is_tax() ? $sign * $price_total : 0;
-            $line_item->add_child_line_item($sub_line_item);
-        }
-        $line_item->setPretaxTotal($running_pre_tax_total);
-        return $line_item;
-    }
-
-
-    /**
-     * Adds the specified item under the pre-tax-sub-total line item. Automatically
-     * re-calculates the line item totals and updates the related transaction. But
-     * DOES NOT automatically upgrade the transaction's registrations' final prices (which
-     * should probably change because of this).
-     * You should call EE_Registration_Processor::calculate_reg_final_prices_per_line_item()
-     * after using this, to keep the registration final prices in-sync with the transaction's total.
-     *
-     * @param EE_Line_Item $total_line_item
-     * @param EE_Line_Item $item to be added
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function add_item(EE_Line_Item $total_line_item, EE_Line_Item $item, $recalculate_totals = true)
-    {
-        $pre_tax_subtotal = self::get_pre_tax_subtotal($total_line_item);
-        if ($pre_tax_subtotal instanceof EE_Line_Item) {
-            $success = $pre_tax_subtotal->add_child_line_item($item);
-        } else {
-            return false;
-        }
-        if ($recalculate_totals) {
-            $total_line_item->recalculate_total_including_taxes();
-        }
-        return $success;
-    }
-
-
-    /**
-     * cancels an existing ticket line item,
-     * by decrementing it's quantity by 1 and adding a new "type_cancellation" sub-line-item.
-     * ALL totals and subtotals will NEED TO BE UPDATED after performing this action
-     *
-     * @param EE_Line_Item $ticket_line_item
-     * @param int          $qty
-     * @return bool success
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function cancel_ticket_line_item(EE_Line_Item $ticket_line_item, $qty = 1)
-    {
-        // validate incoming line_item
-        if ($ticket_line_item->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_TICKET) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'The supplied line item must have an Object Type of "Ticket", not %1$s.',
-                        'event_espresso'
-                    ),
-                    $ticket_line_item->type()
-                )
-            );
-        }
-        if ($ticket_line_item->quantity() < $qty) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'Can not cancel %1$d ticket(s) because the supplied line item has a quantity of %2$d.',
-                        'event_espresso'
-                    ),
-                    $qty,
-                    $ticket_line_item->quantity()
-                )
-            );
-        }
-        // decrement ticket quantity; don't rely on auto-fixing when recalculating totals to do this
-        $ticket_line_item->set_quantity($ticket_line_item->quantity() - $qty);
-        foreach ($ticket_line_item->children() as $child_line_item) {
-            if (
-                $child_line_item->is_sub_line_item()
-                && ! $child_line_item->is_percent()
-                && ! $child_line_item->is_cancellation()
-            ) {
-                $child_line_item->set_quantity($child_line_item->quantity() - $qty);
-            }
-        }
-        // get cancellation sub line item
-        $cancellation_line_item = EEH_Line_Item::get_descendants_of_type(
-            $ticket_line_item,
-            EEM_Line_Item::type_cancellation
-        );
-        $cancellation_line_item = reset($cancellation_line_item);
-        // verify that this ticket was indeed previously cancelled
-        if ($cancellation_line_item instanceof EE_Line_Item) {
-            // increment cancelled quantity
-            $cancellation_line_item->set_quantity($cancellation_line_item->quantity() + $qty);
-        } else {
-            // create cancellation sub line item
-            $cancellation_line_item = EE_Line_Item::new_instance(array(
-                'LIN_name'       => esc_html__('Cancellation', 'event_espresso'),
-                'LIN_desc'       => sprintf(
-                    esc_html_x(
-                        'Cancelled %1$s : %2$s',
-                        'Cancelled Ticket Name : 2015-01-01 11:11',
-                        'event_espresso'
-                    ),
-                    $ticket_line_item->name(),
-                    current_time(get_option('date_format') . ' ' . get_option('time_format'))
-                ),
-                'LIN_unit_price' => 0, // $ticket_line_item->unit_price()
-                'LIN_quantity'   => $qty,
-                'LIN_is_taxable' => $ticket_line_item->is_taxable(),
-                'LIN_order'      => count($ticket_line_item->children()),
-                'LIN_total'      => 0, // $ticket_line_item->unit_price()
-                'LIN_type'       => EEM_Line_Item::type_cancellation,
-            ));
-            $ticket_line_item->add_child_line_item($cancellation_line_item);
-        }
-        if ($ticket_line_item->save_this_and_descendants() > 0) {
-            // decrement parent line item quantity
-            $event_line_item = $ticket_line_item->parent();
-            if (
-                $event_line_item instanceof EE_Line_Item
-                && $event_line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_EVENT
-            ) {
-                $event_line_item->set_quantity($event_line_item->quantity() - $qty);
-                $event_line_item->save();
-            }
-            EEH_Line_Item::get_grand_total_and_recalculate_everything($ticket_line_item);
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * reinstates (un-cancels?) a previously canceled ticket line item,
-     * by incrementing it's quantity by 1, and decrementing it's "type_cancellation" sub-line-item.
-     * ALL totals and subtotals will NEED TO BE UPDATED after performing this action
-     *
-     * @param EE_Line_Item $ticket_line_item
-     * @param int          $qty
-     * @return bool success
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function reinstate_canceled_ticket_line_item(EE_Line_Item $ticket_line_item, $qty = 1)
-    {
-        // validate incoming line_item
-        if ($ticket_line_item->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_TICKET) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'The supplied line item must have an Object Type of "Ticket", not %1$s.',
-                        'event_espresso'
-                    ),
-                    $ticket_line_item->type()
-                )
-            );
-        }
-        // get cancellation sub line item
-        $cancellation_line_item = EEH_Line_Item::get_descendants_of_type(
-            $ticket_line_item,
-            EEM_Line_Item::type_cancellation
-        );
-        $cancellation_line_item = reset($cancellation_line_item);
-        // verify that this ticket was indeed previously cancelled
-        if (! $cancellation_line_item instanceof EE_Line_Item) {
-            return false;
-        }
-        if ($cancellation_line_item->quantity() > $qty) {
-            // decrement cancelled quantity
-            $cancellation_line_item->set_quantity($cancellation_line_item->quantity() - $qty);
-        } elseif ($cancellation_line_item->quantity() === $qty) {
-            // decrement cancelled quantity in case anyone still has the object kicking around
-            $cancellation_line_item->set_quantity($cancellation_line_item->quantity() - $qty);
-            // delete because quantity will end up as 0
-            $cancellation_line_item->delete();
-            // and attempt to destroy the object,
-            // even though PHP won't actually destroy it until it needs the memory
-            unset($cancellation_line_item);
-        } else {
-            // what ?!?! negative quantity ?!?!
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'Can not reinstate %1$d cancelled ticket(s) because the cancelled ticket quantity is only %2$d.',
-                        'event_espresso'
-                    ),
-                    $qty,
-                    $cancellation_line_item->quantity()
-                )
-            );
-        }
-        // increment ticket quantity
-        $ticket_line_item->set_quantity($ticket_line_item->quantity() + $qty);
-        if ($ticket_line_item->save_this_and_descendants() > 0) {
-            // increment parent line item quantity
-            $event_line_item = $ticket_line_item->parent();
-            if (
-                $event_line_item instanceof EE_Line_Item
-                && $event_line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_EVENT
-            ) {
-                $event_line_item->set_quantity($event_line_item->quantity() + $qty);
-            }
-            EEH_Line_Item::get_grand_total_and_recalculate_everything($ticket_line_item);
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * calls EEH_Line_Item::find_transaction_grand_total_for_line_item()
-     * then EE_Line_Item::recalculate_total_including_taxes() on the result
-     *
-     * @param EE_Line_Item $line_item
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function get_grand_total_and_recalculate_everything(EE_Line_Item $line_item)
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($line_item);
-        return $grand_total_line_item->recalculate_total_including_taxes();
-    }
-
-
-    /**
-     * Gets the line item which contains the subtotal of all the items
-     *
-     * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function get_pre_tax_subtotal(EE_Line_Item $total_line_item)
-    {
-        $pre_tax_subtotal = $total_line_item->get_child_line_item('pre-tax-subtotal');
-        return $pre_tax_subtotal instanceof EE_Line_Item
-            ? $pre_tax_subtotal
-            : self::create_pre_tax_subtotal($total_line_item);
-    }
-
-
-    /**
-     * Gets the line item for the taxes subtotal
-     *
-     * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function get_taxes_subtotal(EE_Line_Item $total_line_item)
-    {
-        $taxes = $total_line_item->get_child_line_item('taxes');
-        return $taxes ? $taxes : self::create_taxes_subtotal($total_line_item);
-    }
-
-
-    /**
-     * sets the TXN ID on an EE_Line_Item if passed a valid EE_Transaction object
-     *
-     * @param EE_Line_Item   $line_item
-     * @param EE_Transaction $transaction
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function set_TXN_ID(EE_Line_Item $line_item, $transaction = null)
-    {
-        if ($transaction) {
-            /** @type EEM_Transaction $EEM_Transaction */
-            $EEM_Transaction = EE_Registry::instance()->load_model('Transaction');
-            $TXN_ID = $EEM_Transaction->ensure_is_ID($transaction);
-            $line_item->set_TXN_ID($TXN_ID);
-        }
-    }
-
-
-    /**
-     * Creates a new default total line item for the transaction,
-     * and its tickets subtotal and taxes subtotal line items (and adds the
-     * existing taxes as children of the taxes subtotal line item)
-     *
-     * @param EE_Transaction $transaction
-     * @return EE_Line_Item of type total
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function create_total_line_item($transaction = null)
-    {
-        $total_line_item = EE_Line_Item::new_instance(array(
-            'LIN_code' => 'total',
-            'LIN_name' => esc_html__('Grand Total', 'event_espresso'),
-            'LIN_type' => EEM_Line_Item::type_total,
-            'OBJ_type' => EEM_Line_Item::OBJ_TYPE_TRANSACTION,
-        ));
-        $total_line_item = apply_filters(
-            'FHEE__EEH_Line_Item__create_total_line_item__total_line_item',
-            $total_line_item
-        );
-        self::set_TXN_ID($total_line_item, $transaction);
-        self::create_pre_tax_subtotal($total_line_item, $transaction);
-        self::create_taxes_subtotal($total_line_item, $transaction);
-        return $total_line_item;
-    }
-
-
-    /**
-     * Creates a default items subtotal line item
-     *
-     * @param EE_Line_Item   $total_line_item
-     * @param EE_Transaction $transaction
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected static function create_pre_tax_subtotal(EE_Line_Item $total_line_item, $transaction = null)
-    {
-        $pre_tax_line_item = EE_Line_Item::new_instance(array(
-            'LIN_code' => 'pre-tax-subtotal',
-            'LIN_name' => esc_html__('Pre-Tax Subtotal', 'event_espresso'),
-            'LIN_type' => EEM_Line_Item::type_sub_total,
-        ));
-        $pre_tax_line_item = apply_filters(
-            'FHEE__EEH_Line_Item__create_pre_tax_subtotal__pre_tax_line_item',
-            $pre_tax_line_item
-        );
-        self::set_TXN_ID($pre_tax_line_item, $transaction);
-        $total_line_item->add_child_line_item($pre_tax_line_item);
-        self::create_event_subtotal($pre_tax_line_item, $transaction);
-        return $pre_tax_line_item;
-    }
-
-
-    /**
-     * Creates a line item for the taxes subtotal and finds all the tax prices
-     * and applies taxes to it
-     *
-     * @param EE_Line_Item   $total_line_item of type EEM_Line_Item::type_total
-     * @param EE_Transaction $transaction
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected static function create_taxes_subtotal(EE_Line_Item $total_line_item, $transaction = null)
-    {
-        $tax_line_item = EE_Line_Item::new_instance(array(
-            'LIN_code'  => 'taxes',
-            'LIN_name'  => esc_html__('Taxes', 'event_espresso'),
-            'LIN_type'  => EEM_Line_Item::type_tax_sub_total,
-            'LIN_order' => 1000,// this should always come last
-        ));
-        $tax_line_item = apply_filters(
-            'FHEE__EEH_Line_Item__create_taxes_subtotal__tax_line_item',
-            $tax_line_item
-        );
-        self::set_TXN_ID($tax_line_item, $transaction);
-        $total_line_item->add_child_line_item($tax_line_item);
-        // and lastly, add the actual taxes
-        self::apply_taxes($total_line_item);
-        return $tax_line_item;
-    }
-
-
-    /**
-     * Creates a default items subtotal line item
-     *
-     * @param EE_Line_Item   $pre_tax_line_item
-     * @param EE_Transaction $transaction
-     * @param EE_Event       $event
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function create_event_subtotal(EE_Line_Item $pre_tax_line_item, $transaction = null, $event = null)
-    {
-        $event_line_item = EE_Line_Item::new_instance(array(
-            'LIN_code' => self::get_event_code($event),
-            'LIN_name' => self::get_event_name($event),
-            'LIN_desc' => self::get_event_desc($event),
-            'LIN_type' => EEM_Line_Item::type_sub_total,
-            'OBJ_type' => EEM_Line_Item::OBJ_TYPE_EVENT,
-            'OBJ_ID'   => $event instanceof EE_Event ? $event->ID() : 0,
-        ));
-        $event_line_item = apply_filters(
-            'FHEE__EEH_Line_Item__create_event_subtotal__event_line_item',
-            $event_line_item
-        );
-        self::set_TXN_ID($event_line_item, $transaction);
-        $pre_tax_line_item->add_child_line_item($event_line_item);
-        return $event_line_item;
-    }
-
-
-    /**
-     * Gets what the event ticket's code SHOULD be
-     *
-     * @param EE_Event $event
-     * @return string
-     * @throws EE_Error
-     */
-    public static function get_event_code($event)
-    {
-        return 'event-' . ($event instanceof EE_Event ? $event->ID() : '0');
-    }
-
-
-    /**
-     * Gets the event name
-     *
-     * @param EE_Event $event
-     * @return string
-     * @throws EE_Error
-     */
-    public static function get_event_name($event)
-    {
-        return $event instanceof EE_Event
-            ? mb_substr($event->name(), 0, 245)
-            : esc_html__('Event', 'event_espresso');
-    }
-
-
-    /**
-     * Gets the event excerpt
-     *
-     * @param EE_Event $event
-     * @return string
-     * @throws EE_Error
-     */
-    public static function get_event_desc($event)
-    {
-        return $event instanceof EE_Event ? $event->short_description() : '';
-    }
-
-
-    /**
-     * Given the grand total line item and a ticket, finds the event sub-total
-     * line item the ticket's purchase should be added onto
-     *
-     * @access public
-     * @param EE_Line_Item $grand_total the grand total line item
-     * @param EE_Ticket    $ticket
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function get_event_line_item_for_ticket(EE_Line_Item $grand_total, EE_Ticket $ticket)
-    {
-        $first_datetime = $ticket->first_datetime();
-        if (! $first_datetime instanceof EE_Datetime) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__('The supplied ticket (ID %d) has no datetimes', 'event_espresso'),
-                    $ticket->ID()
-                )
-            );
-        }
-        $event = $first_datetime->event();
-        if (! $event instanceof EE_Event) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'The supplied ticket (ID %d) has no event data associated with it.',
-                        'event_espresso'
-                    ),
-                    $ticket->ID()
-                )
-            );
-        }
-        $events_sub_total = EEH_Line_Item::get_event_line_item($grand_total, $event);
-        if (! $events_sub_total instanceof EE_Line_Item) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'There is no events sub-total for ticket %s on total line item %d',
-                        'event_espresso'
-                    ),
-                    $ticket->ID(),
-                    $grand_total->ID()
-                )
-            );
-        }
-        return $events_sub_total;
-    }
-
-
-    /**
-     * Gets the event line item
-     *
-     * @param EE_Line_Item $grand_total
-     * @param EE_Event     $event
-     * @return EE_Line_Item for the event subtotal which is a child of $grand_total
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function get_event_line_item(EE_Line_Item $grand_total, $event)
-    {
-        /** @type EE_Event $event */
-        $event = EEM_Event::instance()->ensure_is_obj($event, true);
-        $event_line_item = null;
-        $found = false;
-        foreach (EEH_Line_Item::get_event_subtotals($grand_total) as $event_line_item) {
-            // default event subtotal, we should only ever find this the first time this method is called
-            if (! $event_line_item->OBJ_ID()) {
-                // let's use this! but first... set the event details
-                EEH_Line_Item::set_event_subtotal_details($event_line_item, $event);
-                $found = true;
-                break;
-            }
-            if ($event_line_item->OBJ_ID() === $event->ID()) {
-                // found existing line item for this event in the cart, so break out of loop and use this one
-                $found = true;
-                break;
-            }
-        }
-        if (! $found) {
-            // there is no event sub-total yet, so add it
-            $pre_tax_subtotal = EEH_Line_Item::get_pre_tax_subtotal($grand_total);
-            // create a new "event" subtotal below that
-            $event_line_item = EEH_Line_Item::create_event_subtotal($pre_tax_subtotal, null, $event);
-            // and set the event details
-            EEH_Line_Item::set_event_subtotal_details($event_line_item, $event);
-        }
-        return $event_line_item;
-    }
-
-
-    /**
-     * Creates a default items subtotal line item
-     *
-     * @param EE_Line_Item   $event_line_item
-     * @param EE_Event       $event
-     * @param EE_Transaction $transaction
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function set_event_subtotal_details(
-        EE_Line_Item $event_line_item,
-        EE_Event $event,
-        $transaction = null
-    ) {
-        if ($event instanceof EE_Event) {
-            $event_line_item->set_code(self::get_event_code($event));
-            $event_line_item->set_name(self::get_event_name($event));
-            $event_line_item->set_desc(self::get_event_desc($event));
-            $event_line_item->set_OBJ_ID($event->ID());
-        }
-        self::set_TXN_ID($event_line_item, $transaction);
-    }
-
-
-    /**
-     * Finds what taxes should apply, adds them as tax line items under the taxes sub-total,
-     * and recalculates the taxes sub-total and the grand total. Resets the taxes, so
-     * any old taxes are removed
-     *
-     * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
-     * @param bool         $update_txn_status
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    public static function apply_taxes(EE_Line_Item $total_line_item, $update_txn_status = false)
-    {
-        $total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($total_line_item);
-        $taxes_line_item = self::get_taxes_subtotal($total_line_item);
-        $existing_global_taxes = $taxes_line_item->tax_descendants();
-        $updates = false;
-        // loop thru taxes
-        $global_taxes = EEH_Line_Item::getGlobalTaxes();
-        foreach ($global_taxes as $order => $taxes) {
-            foreach ($taxes as $tax) {
-                if ($tax instanceof EE_Price) {
-                    $found = false;
-                    // check if this is already an existing tax
-                    foreach ($existing_global_taxes as $existing_global_tax) {
-                        if ($tax->ID() === $existing_global_tax->OBJ_ID()) {
-                            // maybe update the tax rate in case it has changed
-                            if ($existing_global_tax->percent() !== $tax->amount()) {
-                                $existing_global_tax->set_percent($tax->amount());
-                                $existing_global_tax->save();
-                                $updates = true;
-                            }
-                            $found = true;
-                            break;
-                        }
-                    }
-                    if (! $found) {
-                        // add a new line item for this global tax
-                        $tax_line_item = apply_filters(
-                            'FHEE__EEH_Line_Item__apply_taxes__tax_line_item',
-                            EE_Line_Item::new_instance(
-                                [
-                                    'LIN_name'       => $tax->name(),
-                                    'LIN_desc'       => $tax->desc(),
-                                    'LIN_percent'    => $tax->amount(),
-                                    'LIN_is_taxable' => false,
-                                    'LIN_order'      => $order,
-                                    'LIN_total'      => 0,
-                                    'LIN_type'       => EEM_Line_Item::type_tax,
-                                    'OBJ_type'       => EEM_Line_Item::OBJ_TYPE_PRICE,
-                                    'OBJ_ID'         => $tax->ID(),
-                                ]
-                            )
-                        );
-                        $updates = $taxes_line_item->add_child_line_item($tax_line_item) ? true : $updates;
-                    }
-                }
-            }
-        }
-        // only recalculate totals if something changed
-        if ($updates) {
-            $total_line_item->recalculate_total_including_taxes($update_txn_status);
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * Ensures that taxes have been applied to the order, if not applies them.
-     * Returns the total amount of tax
-     *
-     * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function ensure_taxes_applied($total_line_item)
-    {
-        $taxes_subtotal = self::get_taxes_subtotal($total_line_item);
-        if (! $taxes_subtotal->children()) {
-            self::apply_taxes($total_line_item);
-        }
-        return $taxes_subtotal->total();
-    }
-
-
-    /**
-     * Deletes ALL children of the passed line item
-     *
-     * @param EE_Line_Item $parent_line_item
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function delete_all_child_items(EE_Line_Item $parent_line_item)
-    {
-        $deleted = 0;
-        foreach ($parent_line_item->children() as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item) {
-                $deleted += EEH_Line_Item::delete_all_child_items($child_line_item);
-                if ($child_line_item->ID()) {
-                    $child_line_item->delete();
-                    unset($child_line_item);
-                } else {
-                    $parent_line_item->delete_child_line_item($child_line_item->code());
-                }
-                $deleted++;
-            }
-        }
-        return $deleted;
-    }
-
-
-    /**
-     * Deletes the line items as indicated by the line item code(s) provided,
-     * regardless of where they're found in the line item tree. Automatically
-     * re-calculates the line item totals and updates the related transaction. But
-     * DOES NOT automatically upgrade the transaction's registrations' final prices (which
-     * should probably change because of this).
-     * You should call EE_Registration_Processor::calculate_reg_final_prices_per_line_item()
-     * after using this, to keep the registration final prices in-sync with the transaction's total.
-     *
-     * @param EE_Line_Item      $total_line_item of type EEM_Line_Item::type_total
-     * @param array|bool|string $line_item_codes
-     * @return int number of items successfully removed
-     * @throws EE_Error
-     */
-    public static function delete_items(EE_Line_Item $total_line_item, $line_item_codes = false)
-    {
-
-        if ($total_line_item->type() !== EEM_Line_Item::type_total) {
-            EE_Error::doing_it_wrong(
-                'EEH_Line_Item::delete_items',
-                esc_html__(
-                    'This static method should only be called with a TOTAL line item, otherwise we won\'t recalculate the totals correctly',
-                    'event_espresso'
-                ),
-                '4.6.18'
-            );
-        }
-        do_action('AHEE_log', __FILE__, __FUNCTION__, '');
-
-        // check if only a single line_item_id was passed
-        if (! empty($line_item_codes) && ! is_array($line_item_codes)) {
-            // place single line_item_id in an array to appear as multiple line_item_ids
-            $line_item_codes = array($line_item_codes);
-        }
-        $removals = 0;
-        // cycle thru line_item_ids
-        foreach ($line_item_codes as $line_item_id) {
-            $removals += $total_line_item->delete_child_line_item($line_item_id);
-        }
-
-        if ($removals > 0) {
-            $total_line_item->recalculate_taxes_and_tax_total();
-            return $removals;
-        } else {
-            return false;
-        }
-    }
-
-
-    /**
-     * Overwrites the previous tax by clearing out the old taxes, and creates a new
-     * tax and updates the total line item accordingly
-     *
-     * @param EE_Line_Item $total_line_item
-     * @param float        $amount
-     * @param string       $name
-     * @param string       $description
-     * @param string       $code
-     * @param boolean      $add_to_existing_line_item
-     *                          if true, and a duplicate line item with the same code is found,
-     *                          $amount will be added onto it; otherwise will simply set the taxes to match $amount
-     * @return EE_Line_Item the new tax line item created
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function set_total_tax_to(
-        EE_Line_Item $total_line_item,
-        $amount,
-        $name = null,
-        $description = null,
-        $code = null,
-        $add_to_existing_line_item = false
-    ) {
-        $tax_subtotal = self::get_taxes_subtotal($total_line_item);
-        $taxable_total = $total_line_item->taxable_total();
-
-        if ($add_to_existing_line_item) {
-            $new_tax = $tax_subtotal->get_child_line_item($code);
-            EEM_Line_Item::instance()->delete(
-                array(array('LIN_code' => array('!=', $code), 'LIN_parent' => $tax_subtotal->ID()))
-            );
-        } else {
-            $new_tax = null;
-            $tax_subtotal->delete_children_line_items();
-        }
-        if ($new_tax) {
-            $new_tax->set_total($new_tax->total() + $amount);
-            $new_tax->set_percent($taxable_total ? $new_tax->total() / $taxable_total * 100 : 0);
-        } else {
-            // no existing tax item. Create it
-            $new_tax = EE_Line_Item::new_instance(array(
-                'TXN_ID'      => $total_line_item->TXN_ID(),
-                'LIN_name'    => $name ?: esc_html__('Tax', 'event_espresso'),
-                'LIN_desc'    => $description ?: '',
-                'LIN_percent' => $taxable_total ? ($amount / $taxable_total * 100) : 0,
-                'LIN_total'   => $amount,
-                'LIN_parent'  => $tax_subtotal->ID(),
-                'LIN_type'    => EEM_Line_Item::type_tax,
-                'LIN_code'    => $code,
-            ));
-        }
-
-        $new_tax = apply_filters(
-            'FHEE__EEH_Line_Item__set_total_tax_to__new_tax_subtotal',
-            $new_tax,
-            $total_line_item
-        );
-        $new_tax->save();
-        $tax_subtotal->set_total($new_tax->total());
-        $tax_subtotal->save();
-        $total_line_item->recalculate_total_including_taxes();
-        return $new_tax;
-    }
-
-
-    /**
-     * Makes all the line items which are children of $line_item taxable (or not).
-     * Does NOT save the line items
-     *
-     * @param EE_Line_Item $line_item
-     * @param boolean      $taxable
-     * @param string       $code_substring_for_whitelist if this string is part of the line item's code
-     *                                                   it will be whitelisted (ie, except from becoming taxable)
-     * @throws EE_Error
-     */
-    public static function set_line_items_taxable(
-        EE_Line_Item $line_item,
-        $taxable = true,
-        $code_substring_for_whitelist = null
-    ) {
-        $whitelisted = false;
-        if ($code_substring_for_whitelist !== null) {
-            $whitelisted = strpos($line_item->code(), $code_substring_for_whitelist) !== false;
-        }
-        if (! $whitelisted && $line_item->is_line_item()) {
-            $line_item->set_is_taxable($taxable);
-        }
-        foreach ($line_item->children() as $child_line_item) {
-            EEH_Line_Item::set_line_items_taxable(
-                $child_line_item,
-                $taxable,
-                $code_substring_for_whitelist
-            );
-        }
-    }
-
-
-    /**
-     * Gets all descendants that are event subtotals
-     *
-     * @uses  EEH_Line_Item::get_subtotals_of_object_type()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public static function get_event_subtotals(EE_Line_Item $parent_line_item)
-    {
-        return self::get_subtotals_of_object_type($parent_line_item, EEM_Line_Item::OBJ_TYPE_EVENT);
-    }
-
-
-    /**
-     * Gets all descendants subtotals that match the supplied object type
-     *
-     * @uses  EEH_Line_Item::_get_descendants_by_type_and_object_type()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @param string       $obj_type
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public static function get_subtotals_of_object_type(EE_Line_Item $parent_line_item, $obj_type = '')
-    {
-        return self::_get_descendants_by_type_and_object_type(
-            $parent_line_item,
-            EEM_Line_Item::type_sub_total,
-            $obj_type
-        );
-    }
-
-
-    /**
-     * Gets all descendants that are tickets
-     *
-     * @uses  EEH_Line_Item::get_line_items_of_object_type()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public static function get_ticket_line_items(EE_Line_Item $parent_line_item)
-    {
-        return self::get_line_items_of_object_type(
-            $parent_line_item,
-            EEM_Line_Item::OBJ_TYPE_TICKET
-        );
-    }
-
-
-    /**
-     * Gets all descendants subtotals that match the supplied object type
-     *
-     * @uses  EEH_Line_Item::_get_descendants_by_type_and_object_type()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @param string       $obj_type
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public static function get_line_items_of_object_type(EE_Line_Item $parent_line_item, $obj_type = '')
-    {
-        return self::_get_descendants_by_type_and_object_type(
-            $parent_line_item,
-            EEM_Line_Item::type_line_item,
-            $obj_type
-        );
-    }
-
-
-    /**
-     * Gets all the descendants (ie, children or children of children etc) that are of the type 'tax'
-     *
-     * @uses  EEH_Line_Item::get_descendants_of_type()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public static function get_tax_descendants(EE_Line_Item $parent_line_item)
-    {
-        return EEH_Line_Item::get_descendants_of_type(
-            $parent_line_item,
-            EEM_Line_Item::type_tax
-        );
-    }
-
-
-    /**
-     * Gets all the real items purchased which are children of this item
-     *
-     * @uses  EEH_Line_Item::get_descendants_of_type()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public static function get_line_item_descendants(EE_Line_Item $parent_line_item)
-    {
-        return EEH_Line_Item::get_descendants_of_type(
-            $parent_line_item,
-            EEM_Line_Item::type_line_item
-        );
-    }
-
-
-    /**
-     * Gets all descendants of supplied line item that match the supplied line item type
-     *
-     * @uses  EEH_Line_Item::_get_descendants_by_type_and_object_type()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @param string       $line_item_type   one of the EEM_Line_Item constants
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public static function get_descendants_of_type(EE_Line_Item $parent_line_item, $line_item_type)
-    {
-        return self::_get_descendants_by_type_and_object_type(
-            $parent_line_item,
-            $line_item_type,
-            null
-        );
-    }
-
-
-    /**
-     * Gets all descendants of supplied line item that match the supplied line item type and possibly the object type
-     * as well
-     *
-     * @param EE_Line_Item  $parent_line_item - the line item to find descendants of
-     * @param string        $line_item_type   one of the EEM_Line_Item constants
-     * @param string | NULL $obj_type         object model class name (minus prefix) or NULL to ignore object type when
-     *                                        searching
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    protected static function _get_descendants_by_type_and_object_type(
-        EE_Line_Item $parent_line_item,
-        $line_item_type,
-        $obj_type = null
-    ) {
-        $objects = array();
-        foreach ($parent_line_item->children() as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item) {
-                if (
-                    $child_line_item->type() === $line_item_type
-                    && (
-                        $child_line_item->OBJ_type() === $obj_type || $obj_type === null
-                    )
-                ) {
-                    $objects[] = $child_line_item;
-                } else {
-                    // go-through-all-its children looking for more matches
-                    $objects = array_merge(
-                        $objects,
-                        self::_get_descendants_by_type_and_object_type(
-                            $child_line_item,
-                            $line_item_type,
-                            $obj_type
-                        )
-                    );
-                }
-            }
-        }
-        return $objects;
-    }
-
-
-    /**
-     * Gets all descendants subtotals that match the supplied object type
-     *
-     * @uses  EEH_Line_Item::_get_descendants_by_type_and_object_type()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @param string       $OBJ_type         object type (like Event)
-     * @param array        $OBJ_IDs          array of OBJ_IDs
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public static function get_line_items_by_object_type_and_IDs(
-        EE_Line_Item $parent_line_item,
-        $OBJ_type = '',
-        $OBJ_IDs = array()
-    ) {
-        return self::_get_descendants_by_object_type_and_object_ID(
-            $parent_line_item,
-            $OBJ_type,
-            $OBJ_IDs
-        );
-    }
-
-
-    /**
-     * Gets all descendants of supplied line item that match the supplied line item type and possibly the object type
-     * as well
-     *
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @param string       $OBJ_type         object type (like Event)
-     * @param array        $OBJ_IDs          array of OBJ_IDs
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     */
-    protected static function _get_descendants_by_object_type_and_object_ID(
-        EE_Line_Item $parent_line_item,
-        $OBJ_type,
-        $OBJ_IDs
-    ) {
-        $objects = array();
-        foreach ($parent_line_item->children() as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item) {
-                if (
-                    $child_line_item->OBJ_type() === $OBJ_type
-                    && is_array($OBJ_IDs)
-                    && in_array($child_line_item->OBJ_ID(), $OBJ_IDs)
-                ) {
-                    $objects[] = $child_line_item;
-                } else {
-                    // go-through-all-its children looking for more matches
-                    $objects = array_merge(
-                        $objects,
-                        self::_get_descendants_by_object_type_and_object_ID(
-                            $child_line_item,
-                            $OBJ_type,
-                            $OBJ_IDs
-                        )
-                    );
-                }
-            }
-        }
-        return $objects;
-    }
-
-
-    /**
-     * Uses a breadth-first-search in order to find the nearest descendant of
-     * the specified type and returns it, else NULL
-     *
-     * @uses  EEH_Line_Item::_get_nearest_descendant()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @param string       $type             like one of the EEM_Line_Item::type_*
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function get_nearest_descendant_of_type(EE_Line_Item $parent_line_item, $type)
-    {
-        return self::_get_nearest_descendant($parent_line_item, 'LIN_type', $type);
-    }
-
-
-    /**
-     * Uses a breadth-first-search in order to find the nearest descendant
-     * having the specified LIN_code and returns it, else NULL
-     *
-     * @uses  EEH_Line_Item::_get_nearest_descendant()
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @param string       $code             any value used for LIN_code
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function get_nearest_descendant_having_code(EE_Line_Item $parent_line_item, $code)
-    {
-        return self::_get_nearest_descendant($parent_line_item, 'LIN_code', $code);
-    }
-
-
-    /**
-     * Uses a breadth-first-search in order to find the nearest descendant
-     * having the specified LIN_code and returns it, else NULL
-     *
-     * @param EE_Line_Item $parent_line_item - the line item to find descendants of
-     * @param string       $search_field     name of EE_Line_Item property
-     * @param string       $value            any value stored in $search_field
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected static function _get_nearest_descendant(EE_Line_Item $parent_line_item, $search_field, $value)
-    {
-        foreach ($parent_line_item->children() as $child) {
-            if ($child->get($search_field) == $value) {
-                return $child;
-            }
-        }
-        foreach ($parent_line_item->children() as $child) {
-            $descendant_found = self::_get_nearest_descendant(
-                $child,
-                $search_field,
-                $value
-            );
-            if ($descendant_found) {
-                return $descendant_found;
-            }
-        }
-        return null;
-    }
-
-
-    /**
-     * if passed line item has a TXN ID, uses that to jump directly to the grand total line item for the transaction,
-     * else recursively walks up the line item tree until a parent of type total is found,
-     *
-     * @param EE_Line_Item $line_item
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function find_transaction_grand_total_for_line_item(EE_Line_Item $line_item): EE_Line_Item
-    {
-        if ($line_item->is_total()) {
-            return $line_item;
-        }
-        if ($line_item->TXN_ID()) {
-            $total_line_item = $line_item->transaction()->total_line_item(false);
-            if ($total_line_item instanceof EE_Line_Item) {
-                return $total_line_item;
-            }
-        } else {
-            $line_item_parent = $line_item->parent();
-            if ($line_item_parent instanceof EE_Line_Item) {
-                if ($line_item_parent->is_total()) {
-                    return $line_item_parent;
-                }
-                return EEH_Line_Item::find_transaction_grand_total_for_line_item($line_item_parent);
-            }
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    'A valid grand total for line item %1$d was not found.',
-                    'event_espresso'
-                ),
-                $line_item->ID()
-            )
-        );
-    }
-
-
-    /**
-     * Prints out a representation of the line item tree
-     *
-     * @param EE_Line_Item $line_item
-     * @param int          $indentation
-     * @return void
-     * @throws EE_Error
-     */
-    public static function visualize(EE_Line_Item $line_item, $indentation = 0)
-    {
-        $new_line = defined('EE_TESTS_DIR') ? "\n" : '<br />';
-        echo $new_line;
-        if (! $indentation) {
-            echo $new_line;
-        }
-        echo str_repeat('. ', $indentation);
-        $breakdown = '';
-        if ($line_item->is_line_item() || $line_item->is_sub_line_item() || $line_item->isSubTax()) {
-            if ($line_item->is_percent()) {
-                $breakdown = "{$line_item->percent()}%";
-            } else {
-                $breakdown = "\${$line_item->unit_price()} x {$line_item->quantity()}";
-            }
-        }
-        echo wp_kses($line_item->name(), AllowedTags::getAllowedTags());
-        echo " [ ID:{$line_item->ID()} | qty:{$line_item->quantity()} ] {$line_item->type()} : ";
-        echo "\${$line_item->total()}";
-        if ($breakdown) {
-            echo " ( {$breakdown} )";
-        }
-        if ($line_item->is_taxable()) {
-            echo '  * taxable';
-        }
-        if ($line_item->children()) {
-            foreach ($line_item->children() as $child) {
-                self::visualize($child, $indentation + 1);
-            }
-        }
-        if (! $indentation) {
-            echo $new_line . $new_line;
-        }
-    }
-
-
-    /**
-     * Calculates the registration's final price, taking into account that they
-     * need to not only help pay for their OWN ticket, but also any transaction-wide surcharges and taxes,
-     * and receive a portion of any transaction-wide discounts.
-     * eg1, if I buy a $1 ticket and brent buys a $9 ticket, and we receive a $5 discount
-     * then I'll get 1/10 of that $5 discount, which is $0.50, and brent will get
-     * 9/10ths of that $5 discount, which is $4.50. So my final price should be $0.50
-     * and brent's final price should be $5.50.
-     * In order to do this, we basically need to traverse the line item tree calculating
-     * the running totals (just as if we were recalculating the total), but when we identify
-     * regular line items, we need to keep track of their share of the grand total.
-     * Also, we need to keep track of the TAXABLE total for each ticket purchase, so
-     * we can know how to apply taxes to it. (Note: "taxable total" does not equal the "pretax total"
-     * when there are non-taxable items; otherwise they would be the same)
-     *
-     * @param EE_Line_Item $line_item
-     * @param array        $billable_ticket_quantities  array of EE_Ticket IDs and their corresponding quantity that
-     *                                                  can be included in price calculations at this moment
-     * @return array        keys are line items for tickets IDs and values are their share of the running total,
-     *                                                  plus the key 'total', and 'taxable' which also has keys of all
-     *                                                  the ticket IDs.
-     *                                                  Eg array(
-     *                                                      12 => 4.3
-     *                                                      23 => 8.0
-     *                                                      'total' => 16.6,
-     *                                                      'taxable' => array(
-     *                                                          12 => 10,
-     *                                                          23 => 4
-     *                                                      ).
-     *                                                  So to find which registrations have which final price, we need
-     *                                                  to find which line item is theirs, which can be done with
-     *                                                  `EEM_Line_Item::instance()->get_line_item_for_registration(
-     *                                                  $registration );`
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function calculate_reg_final_prices_per_line_item(
-        EE_Line_Item $line_item,
-        $billable_ticket_quantities = array()
-    ) {
-        $running_totals = [
-            'total'   => 0,
-            'taxable' => ['total' => 0]
-        ];
-        foreach ($line_item->children() as $child_line_item) {
-            switch ($child_line_item->type()) {
-                case EEM_Line_Item::type_sub_total:
-                    $running_totals_from_subtotal = EEH_Line_Item::calculate_reg_final_prices_per_line_item(
-                        $child_line_item,
-                        $billable_ticket_quantities
-                    );
-                    // combine arrays but preserve numeric keys
-                    $running_totals = array_replace_recursive($running_totals_from_subtotal, $running_totals);
-                    $running_totals['total'] += $running_totals_from_subtotal['total'];
-                    $running_totals['taxable']['total'] += $running_totals_from_subtotal['taxable']['total'];
-                    break;
-
-                case EEM_Line_Item::type_tax_sub_total:
-                    // find how much the taxes percentage is
-                    if ($child_line_item->percent() !== 0) {
-                        $tax_percent_decimal = $child_line_item->percent() / 100;
-                    } else {
-                        $tax_percent_decimal = EE_Taxes::get_total_taxes_percentage() / 100;
-                    }
-                    // and apply to all the taxable totals, and add to the pretax totals
-                    foreach ($running_totals as $line_item_id => $this_running_total) {
-                        // "total" and "taxable" array key is an exception
-                        if ($line_item_id === 'taxable') {
-                            continue;
-                        }
-                        $taxable_total = $running_totals['taxable'][ $line_item_id ];
-                        $running_totals[ $line_item_id ] += ($taxable_total * $tax_percent_decimal);
-                    }
-                    break;
-
-                case EEM_Line_Item::type_line_item:
-                    // ticket line items or ????
-                    if ($child_line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET) {
-                        // kk it's a ticket
-                        if (isset($running_totals[ $child_line_item->ID() ])) {
-                            // huh? that shouldn't happen.
-                            $running_totals['total'] += $child_line_item->total();
-                        } else {
-                            // its not in our running totals yet. great.
-                            if ($child_line_item->is_taxable()) {
-                                $taxable_amount = $child_line_item->unit_price();
-                            } else {
-                                $taxable_amount = 0;
-                            }
-                            // are we only calculating totals for some tickets?
-                            if (isset($billable_ticket_quantities[ $child_line_item->OBJ_ID() ])) {
-                                $quantity = $billable_ticket_quantities[ $child_line_item->OBJ_ID() ];
-                                $running_totals[ $child_line_item->ID() ] = $quantity
-                                    ? $child_line_item->unit_price()
-                                    : 0;
-                                $running_totals['taxable'][ $child_line_item->ID() ] = $quantity
-                                    ? $taxable_amount
-                                    : 0;
-                            } else {
-                                $quantity = $child_line_item->quantity();
-                                $running_totals[ $child_line_item->ID() ] = $child_line_item->unit_price();
-                                $running_totals['taxable'][ $child_line_item->ID() ] = $taxable_amount;
-                            }
-                            $running_totals['taxable']['total'] += $taxable_amount * $quantity;
-                            $running_totals['total'] += $child_line_item->unit_price() * $quantity;
-                        }
-                    } else {
-                        // it's some other type of item added to the cart
-                        // it should affect the running totals
-                        // basically we want to convert it into a PERCENT modifier. Because
-                        // more clearly affect all registration's final price equally
-                        $line_items_percent_of_running_total = $running_totals['total'] > 0
-                            ? ($child_line_item->total() / $running_totals['total']) + 1
-                            : 1;
-                        foreach ($running_totals as $line_item_id => $this_running_total) {
-                            // the "taxable" array key is an exception
-                            if ($line_item_id === 'taxable') {
-                                continue;
-                            }
-                            // update the running totals
-                            // yes this actually even works for the running grand total!
-                            $running_totals[ $line_item_id ] =
-                                $line_items_percent_of_running_total * $this_running_total;
-
-                            if ($child_line_item->is_taxable()) {
-                                $running_totals['taxable'][ $line_item_id ] =
-                                    $line_items_percent_of_running_total * $running_totals['taxable'][ $line_item_id ];
-                            }
-                        }
-                    }
-                    break;
-            }
-        }
-        return $running_totals;
-    }
-
-
-    /**
-     * @param EE_Line_Item $total_line_item
-     * @param EE_Line_Item $ticket_line_item
-     * @return float | null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws OutOfRangeException
-     * @throws ReflectionException
-     */
-    public static function calculate_final_price_for_ticket_line_item(
-        EE_Line_Item $total_line_item,
-        EE_Line_Item $ticket_line_item
-    ) {
-        static $final_prices_per_ticket_line_item = array();
-        if (empty($final_prices_per_ticket_line_item) || empty($final_prices_per_ticket_line_item[ $total_line_item->ID() ])) {
-            $final_prices_per_ticket_line_item[ $total_line_item->ID() ] = EEH_Line_Item::calculate_reg_final_prices_per_line_item(
-                $total_line_item
-            );
-        }
-        // ok now find this new registration's final price
-        if (isset($final_prices_per_ticket_line_item[ $total_line_item->ID() ][ $ticket_line_item->ID() ])) {
-            return $final_prices_per_ticket_line_item[ $total_line_item->ID() ][ $ticket_line_item->ID() ];
-        }
-        $message = sprintf(
-            esc_html__(
-                'The final price for the ticket line item (ID:%1$d) on the total line item (ID:%2$d) could not be calculated.',
-                'event_espresso'
-            ),
-            $ticket_line_item->ID(),
-            $total_line_item->ID()
-        );
-        if (WP_DEBUG) {
-            $message .= '<br>' . print_r($final_prices_per_ticket_line_item, true);
-            throw new OutOfRangeException($message);
-        }
-        EE_Log::instance()->log(__CLASS__, __FUNCTION__, $message);
-        return null;
-    }
-
-
-    /**
-     * Creates a duplicate of the line item tree, except only includes billable items
-     * and the portion of line items attributed to billable things
-     *
-     * @param EE_Line_Item      $line_item
-     * @param EE_Registration[] $registrations
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function billable_line_item_tree(EE_Line_Item $line_item, $registrations)
-    {
-        $copy_li = EEH_Line_Item::billable_line_item($line_item, $registrations);
-        foreach ($line_item->children() as $child_li) {
-            $copy_li->add_child_line_item(
-                EEH_Line_Item::billable_line_item_tree($child_li, $registrations)
-            );
-        }
-        // if this is the grand total line item, make sure the totals all add up
-        // (we could have duplicated this logic AS we copied the line items, but
-        // it seems DRYer this way)
-        if ($copy_li->type() === EEM_Line_Item::type_total) {
-            $copy_li->recalculate_total_including_taxes();
-        }
-        return $copy_li;
-    }
-
-
-    /**
-     * Creates a new, unsaved line item from $line_item that factors in the
-     * number of billable registrations on $registrations.
-     *
-     * @param EE_Line_Item      $line_item
-     * @param EE_Registration[] $registrations
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function billable_line_item(EE_Line_Item $line_item, $registrations)
-    {
-        $new_li_fields = $line_item->model_field_array();
-        if (
-            $line_item->type() === EEM_Line_Item::type_line_item &&
-            $line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET
-        ) {
-            $count = 0;
-            foreach ($registrations as $registration) {
-                if (
-                    $line_item->OBJ_ID() === $registration->ticket_ID() &&
-                    in_array(
-                        $registration->status_ID(),
-                        EEM_Registration::reg_statuses_that_allow_payment(),
-                        true
-                    )
-                ) {
-                    $count++;
-                }
-            }
-            $new_li_fields['LIN_quantity'] = $count;
-        }
-        // don't set the total. We'll leave that up to the code that calculates it
-        unset($new_li_fields['LIN_ID'], $new_li_fields['LIN_parent'], $new_li_fields['LIN_total']);
-        return EE_Line_Item::new_instance($new_li_fields);
-    }
-
-
-    /**
-     * Returns a modified line item tree where all the subtotals which have a total of 0
-     * are removed, and line items with a quantity of 0
-     *
-     * @param EE_Line_Item $line_item |null
-     * @return EE_Line_Item|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function non_empty_line_items(EE_Line_Item $line_item)
-    {
-        $copied_li = EEH_Line_Item::non_empty_line_item($line_item);
-        if ($copied_li === null) {
-            return null;
-        }
-        // if this is an event subtotal, we want to only include it if it
-        // has a non-zero total and at least one ticket line item child
-        $ticket_children = 0;
-        foreach ($line_item->children() as $child_li) {
-            $child_li_copy = EEH_Line_Item::non_empty_line_items($child_li);
-            if ($child_li_copy !== null) {
-                $copied_li->add_child_line_item($child_li_copy);
-                if (
-                    $child_li_copy->type() === EEM_Line_Item::type_line_item &&
-                    $child_li_copy->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET
-                ) {
-                    $ticket_children++;
-                }
-            }
-        }
-        // if this is an event subtotal with NO ticket children
-        // we basically want to ignore it
-        if (
-            $ticket_children === 0
-            && $line_item->type() === EEM_Line_Item::type_sub_total
-            && $line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_EVENT
-            && $line_item->total() === 0
-        ) {
-            return null;
-        }
-        return $copied_li;
-    }
-
-
-    /**
-     * Creates a new, unsaved line item, but if it's a ticket line item
-     * with a total of 0, or a subtotal of 0, returns null instead
-     *
-     * @param EE_Line_Item $line_item
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function non_empty_line_item(EE_Line_Item $line_item)
-    {
-        if (
-            $line_item->type() === EEM_Line_Item::type_line_item
-            && $line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET
-            && $line_item->quantity() === 0
-        ) {
-            return null;
-        }
-        $new_li_fields = $line_item->model_field_array();
-        // don't set the total. We'll leave that up to the code that calculates it
-        unset($new_li_fields['LIN_ID'], $new_li_fields['LIN_parent']);
-        return EE_Line_Item::new_instance($new_li_fields);
-    }
-
-
-    /**
-     * Cycles through all of the ticket line items for the supplied total line item
-     * and ensures that the line item's "is_taxable" field matches that of its corresponding ticket
-     *
-     * @param EE_Line_Item $total_line_item
-     * @since 4.9.79.p
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function resetIsTaxableForTickets(EE_Line_Item $total_line_item)
-    {
-        $ticket_line_items = self::get_ticket_line_items($total_line_item);
-        foreach ($ticket_line_items as $ticket_line_item) {
-            if (
-                $ticket_line_item instanceof EE_Line_Item
-                && $ticket_line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET
-            ) {
-                $ticket = $ticket_line_item->ticket();
-                if ($ticket instanceof EE_Ticket && $ticket->taxable() !== $ticket_line_item->is_taxable()) {
-                    $ticket_line_item->set_is_taxable($ticket->taxable());
-                    $ticket_line_item->save();
-                }
-            }
-        }
-    }
-
-
-    /**
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since   $VID:$
-     */
-    private static function getGlobalTaxes(): array
-    {
-        if (EEH_Line_Item::$global_taxes === null) {
-
-            /** @type EEM_Price $EEM_Price */
-            $EEM_Price = EE_Registry::instance()->load_model('Price');
-            // get array of taxes via Price Model
-            EEH_Line_Item::$global_taxes = $EEM_Price->get_all_prices_that_are_taxes();
-            ksort(EEH_Line_Item::$global_taxes);
-        }
-        return EEH_Line_Item::$global_taxes;
-    }
-
-
-
-    /**************************************** @DEPRECATED METHODS *************************************** */
-    /**
-     * @deprecated
-     * @param EE_Line_Item $total_line_item
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function get_items_subtotal(EE_Line_Item $total_line_item)
-    {
-        EE_Error::doing_it_wrong(
-            'EEH_Line_Item::get_items_subtotal()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::get_pre_tax_subtotal()'
-            ),
-            '4.6.0'
-        );
-        return self::get_pre_tax_subtotal($total_line_item);
-    }
-
-
-    /**
-     * @deprecated
-     * @param EE_Transaction $transaction
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function create_default_total_line_item($transaction = null)
-    {
-        EE_Error::doing_it_wrong(
-            'EEH_Line_Item::create_default_total_line_item()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::create_total_line_item()'
-            ),
-            '4.6.0'
-        );
-        return self::create_total_line_item($transaction);
-    }
-
-
-    /**
-     * @deprecated
-     * @param EE_Line_Item   $total_line_item
-     * @param EE_Transaction $transaction
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function create_default_tickets_subtotal(EE_Line_Item $total_line_item, $transaction = null)
-    {
-        EE_Error::doing_it_wrong(
-            'EEH_Line_Item::create_default_tickets_subtotal()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::create_pre_tax_subtotal()'
-            ),
-            '4.6.0'
-        );
-        return self::create_pre_tax_subtotal($total_line_item, $transaction);
-    }
-
-
-    /**
-     * @deprecated
-     * @param EE_Line_Item   $total_line_item
-     * @param EE_Transaction $transaction
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function create_default_taxes_subtotal(EE_Line_Item $total_line_item, $transaction = null)
-    {
-        EE_Error::doing_it_wrong(
-            'EEH_Line_Item::create_default_taxes_subtotal()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::create_taxes_subtotal()'
-            ),
-            '4.6.0'
-        );
-        return self::create_taxes_subtotal($total_line_item, $transaction);
-    }
-
-
-    /**
-     * @deprecated
-     * @param EE_Line_Item   $total_line_item
-     * @param EE_Transaction $transaction
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function create_default_event_subtotal(EE_Line_Item $total_line_item, $transaction = null)
-    {
-        EE_Error::doing_it_wrong(
-            'EEH_Line_Item::create_default_event_subtotal()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::create_event_subtotal()'
-            ),
-            '4.6.0'
-        );
-        return self::create_event_subtotal($total_line_item, $transaction);
-    }
+	/**
+	 * @var EE_Line_Item[]
+	 */
+	private static $global_taxes;
+
+
+	/**
+	 * Adds a simple item (unrelated to any other model object) to the provided PARENT line item.
+	 * Does NOT automatically re-calculate the line item totals or update the related transaction.
+	 * You should call recalculate_total_including_taxes() on the grant total line item after this
+	 * to update the subtotals, and EE_Registration_Processor::calculate_reg_final_prices_per_line_item()
+	 * to keep the registration final prices in-sync with the transaction's total.
+	 *
+	 * @param EE_Line_Item $parent_line_item
+	 * @param string       $name
+	 * @param float        $unit_price
+	 * @param string       $description
+	 * @param int          $quantity
+	 * @param boolean      $taxable
+	 * @param string|null  $code if set to a value, ensures there is only one line item with that code
+	 * @param bool         $return_item
+	 * @param bool         $recalculate_totals
+	 * @return boolean|EE_Line_Item success
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function add_unrelated_item(
+		EE_Line_Item $parent_line_item,
+		string $name,
+		float $unit_price,
+		string $description = '',
+		int $quantity = 1,
+		bool $taxable = false,
+		?string $code = null,
+		bool $return_item = false,
+		bool $recalculate_totals = true
+	) {
+		$items_subtotal = self::get_pre_tax_subtotal($parent_line_item);
+		$line_item      = EE_Line_Item::new_instance(
+			[
+				'LIN_name'       => $name,
+				'LIN_desc'       => $description,
+				'LIN_unit_price' => $unit_price,
+				'LIN_quantity'   => $quantity,
+				'LIN_percent'    => null,
+				'LIN_is_taxable' => $taxable,
+				'LIN_order'      => $items_subtotal instanceof EE_Line_Item
+					? count($items_subtotal->children())
+					: 0,
+				'LIN_total'      => (float) $unit_price * (int) $quantity,
+				'LIN_type'       => EEM_Line_Item::type_line_item,
+				'LIN_code'       => $code,
+			]
+		);
+		$line_item      = apply_filters(
+			'FHEE__EEH_Line_Item__add_unrelated_item__line_item',
+			$line_item,
+			$parent_line_item
+		);
+		$added          = self::add_item($parent_line_item, $line_item, $recalculate_totals);
+		return $return_item ? $line_item : $added;
+	}
+
+
+	/**
+	 * Adds a simple item ( unrelated to any other model object) to the total line item,
+	 * in the correct spot in the line item tree. Does not automatically
+	 * re-calculate the line item totals, nor update the related transaction, nor upgrade the transaction's
+	 * registrations' final prices (which should probably change because of this).
+	 * You should call recalculate_total_including_taxes() on the grand total line item, then
+	 * update the transaction's total, and EE_Registration_Processor::update_registration_final_prices()
+	 * after using this, to keep the registration final prices in-sync with the transaction's total.
+	 *
+	 * @param EE_Line_Item $parent_line_item
+	 * @param string       $name
+	 * @param float        $percentage_amount
+	 * @param string       $description
+	 * @param boolean      $taxable
+	 * @param string|null  $code
+	 * @param bool         $return_item
+	 * @return boolean|EE_Line_Item success
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function add_percentage_based_item(
+		EE_Line_Item $parent_line_item,
+		string $name,
+		float $percentage_amount,
+		string $description = '',
+		bool $taxable = false,
+		?string $code = null,
+		bool $return_item = false
+	) {
+		$total = $percentage_amount * $parent_line_item->total() / 100;
+		$line_item = EE_Line_Item::new_instance(
+			[
+				'LIN_name'       => $name,
+				'LIN_desc'       => $description,
+				'LIN_unit_price' => 0,
+				'LIN_percent'    => $percentage_amount,
+				'LIN_quantity'   => 1,
+				'LIN_is_taxable' => $taxable,
+				'LIN_total'      => (float) $total,
+				'LIN_type'       => EEM_Line_Item::type_line_item,
+				'LIN_parent'     => $parent_line_item->ID(),
+				'LIN_code'       => $code,
+			]
+		);
+		$line_item = apply_filters(
+			'FHEE__EEH_Line_Item__add_percentage_based_item__line_item',
+			$line_item
+		);
+		$added     = $parent_line_item->add_child_line_item($line_item, false);
+		return $return_item ? $line_item : $added;
+	}
+
+
+	/**
+	 * Returns the new line item created by adding a purchase of the ticket
+	 * ensures that ticket line item is saved, and that cart total has been recalculated.
+	 * If this ticket has already been purchased, just increments its count.
+	 * Automatically re-calculates the line item totals and updates the related transaction. But
+	 * DOES NOT automatically upgrade the transaction's registrations' final prices (which
+	 * should probably change because of this).
+	 * You should call EE_Registration_Processor::calculate_reg_final_prices_per_line_item()
+	 * after using this, to keep the registration final prices in-sync with the transaction's total.
+	 *
+	 * @param EE_Line_Item|null $total_line_item grand total line item of type EEM_Line_Item::type_total
+	 * @param EE_Ticket         $ticket
+	 * @param int               $qty
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function add_ticket_purchase(
+		?EE_Line_Item $total_line_item,
+		EE_Ticket $ticket,
+		int $qty = 1
+	): ?EE_Line_Item {
+		if (! $total_line_item instanceof EE_Line_Item || ! $total_line_item->is_total()) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'A valid line item total is required in order to add tickets. A line item of type "%s" was passed.',
+						'event_espresso'
+					),
+					$ticket->ID(),
+					$total_line_item->ID()
+				)
+			);
+		}
+		// either increment the qty for an existing ticket
+		$line_item = self::increment_ticket_qty_if_already_in_cart($total_line_item, $ticket, $qty);
+		// or add a new one
+		if (! $line_item instanceof EE_Line_Item) {
+			$line_item = self::create_ticket_line_item($total_line_item, $ticket, $qty);
+		}
+		$total_line_item->recalculate_total_including_taxes();
+		return $line_item;
+	}
+
+
+	/**
+	 * Returns the new line item created by adding a purchase of the ticket
+	 *
+	 * @param EE_Line_Item $total_line_item
+	 * @param EE_Ticket    $ticket
+	 * @param int          $qty
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function increment_ticket_qty_if_already_in_cart(
+		EE_Line_Item $total_line_item,
+		EE_Ticket $ticket,
+		$qty = 1
+	) {
+		$line_item = null;
+		if ($total_line_item instanceof EE_Line_Item && $total_line_item->is_total()) {
+			$ticket_line_items = EEH_Line_Item::get_ticket_line_items($total_line_item);
+			foreach ($ticket_line_items as $ticket_line_item) {
+				if (
+					$ticket_line_item instanceof EE_Line_Item
+					&& (int) $ticket_line_item->OBJ_ID() === (int) $ticket->ID()
+				) {
+					$line_item = $ticket_line_item;
+					break;
+				}
+			}
+		}
+		if ($line_item instanceof EE_Line_Item) {
+			EEH_Line_Item::increment_quantity($line_item, $qty);
+			return $line_item;
+		}
+		return null;
+	}
+
+
+	/**
+	 * Increments the line item and all its children's quantity by $qty (but percent line items are unaffected).
+	 * Does NOT save or recalculate other line items totals
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @param int          $qty
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function increment_quantity(EE_Line_Item $line_item, $qty = 1)
+	{
+		if (! $line_item->is_percent()) {
+			$qty += $line_item->quantity();
+			$line_item->set_quantity($qty);
+			$line_item->set_total($line_item->unit_price() * $qty);
+			$line_item->save();
+		}
+		foreach ($line_item->children() as $child) {
+			if ($child->is_sub_line_item()) {
+				EEH_Line_Item::update_quantity($child, $qty);
+			}
+		}
+	}
+
+
+	/**
+	 * Decrements the line item and all its children's quantity by $qty (but percent line items are unaffected).
+	 * Does NOT save or recalculate other line items totals
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @param int          $qty
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function decrement_quantity(EE_Line_Item $line_item, $qty = 1)
+	{
+		if (! $line_item->is_percent()) {
+			$qty = $line_item->quantity() - $qty;
+			$qty = max($qty, 0);
+			$line_item->set_quantity($qty);
+			$line_item->set_total($line_item->unit_price() * $qty);
+			$line_item->save();
+		}
+		foreach ($line_item->children() as $child) {
+			if ($child->is_sub_line_item()) {
+				EEH_Line_Item::update_quantity($child, $qty);
+			}
+		}
+	}
+
+
+	/**
+	 * Updates the line item and its children's quantities to the specified number.
+	 * Does NOT save them or recalculate totals.
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @param int          $new_quantity
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function update_quantity(EE_Line_Item $line_item, $new_quantity)
+	{
+		if (! $line_item->is_percent()) {
+			$line_item->set_quantity($new_quantity);
+			$line_item->set_total($line_item->unit_price() * $new_quantity);
+			$line_item->save();
+		}
+		foreach ($line_item->children() as $child) {
+			if ($child->is_sub_line_item()) {
+				EEH_Line_Item::update_quantity($child, $new_quantity);
+			}
+		}
+	}
+
+
+	/**
+	 * Returns the new line item created by adding a purchase of the ticket
+	 *
+	 * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
+	 * @param EE_Ticket    $ticket
+	 * @param int          $qty
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function create_ticket_line_item(EE_Line_Item $total_line_item, EE_Ticket $ticket, $qty = 1)
+	{
+		$datetimes = $ticket->datetimes();
+		$first_datetime = reset($datetimes);
+		$first_datetime_name = esc_html__('Event', 'event_espresso');
+		if ($first_datetime instanceof EE_Datetime && $first_datetime->event() instanceof EE_Event) {
+			$first_datetime_name = $first_datetime->event()->name();
+		}
+		$event = sprintf(_x('(For %1$s)', '(For Event Name)', 'event_espresso'), $first_datetime_name);
+		// get event subtotal line
+		$events_sub_total = self::get_event_line_item_for_ticket($total_line_item, $ticket);
+		$taxes = $ticket->tax_price_modifiers();
+		// add $ticket to cart
+		$line_item = EE_Line_Item::new_instance(array(
+			'LIN_name'       => $ticket->name(),
+			'LIN_desc'       => $ticket->description() !== '' ? $ticket->description() . ' ' . $event : $event,
+			'LIN_unit_price' => $ticket->price(),
+			'LIN_quantity'   => $qty,
+			'LIN_is_taxable' => empty($taxes) && $ticket->taxable(),
+			'LIN_order'      => count($events_sub_total->children()),
+			'LIN_total'      => $ticket->price() * $qty,
+			'LIN_type'       => EEM_Line_Item::type_line_item,
+			'OBJ_ID'         => $ticket->ID(),
+			'OBJ_type'       => EEM_Line_Item::OBJ_TYPE_TICKET,
+		));
+		$line_item = apply_filters(
+			'FHEE__EEH_Line_Item__create_ticket_line_item__line_item',
+			$line_item
+		);
+		if (!$line_item instanceof EE_Line_Item) {
+			throw new DomainException(
+				esc_html__('Invalid EE_Line_Item received.', 'event_espresso')
+			);
+		}
+		$events_sub_total->add_child_line_item($line_item);
+		// now add the sub-line items
+		$running_total = 0;
+		$running_pre_tax_total = 0;
+		foreach ($ticket->prices() as $price) {
+			$sign = $price->is_discount() ? -1 : 1;
+			$price_total = $price->is_percent()
+				? $running_pre_tax_total * $price->amount() / 100
+				: $price->amount() * $qty;
+			if ($price->is_percent()) {
+				$percent = $sign * $price->amount();
+				$unit_price = 0;
+			} else {
+				$percent    = 0;
+				$unit_price = $sign * $price->amount();
+			}
+			$sub_line_item = EE_Line_Item::new_instance(array(
+				'LIN_name'       => $price->name(),
+				'LIN_desc'       => $price->desc(),
+				'LIN_quantity'   => $price->is_percent() ? null : $qty,
+				'LIN_is_taxable' => false,
+				'LIN_order'      => $price->order(),
+				'LIN_total'      => $price_total,
+				'LIN_pretax'     => 0,
+				'LIN_unit_price' => $unit_price,
+				'LIN_percent'    => $percent,
+				'LIN_type'       => $price->is_tax() ? EEM_Line_Item::type_sub_tax : EEM_Line_Item::type_sub_line_item,
+				'OBJ_ID'         => $price->ID(),
+				'OBJ_type'       => EEM_Line_Item::OBJ_TYPE_PRICE,
+			));
+			$sub_line_item = apply_filters(
+				'FHEE__EEH_Line_Item__create_ticket_line_item__sub_line_item',
+				$sub_line_item
+			);
+			$running_total += $sign * $price_total;
+			$running_pre_tax_total += ! $price->is_tax() ? $sign * $price_total : 0;
+			$line_item->add_child_line_item($sub_line_item);
+		}
+		$line_item->setPretaxTotal($running_pre_tax_total);
+		return $line_item;
+	}
+
+
+	/**
+	 * Adds the specified item under the pre-tax-sub-total line item. Automatically
+	 * re-calculates the line item totals and updates the related transaction. But
+	 * DOES NOT automatically upgrade the transaction's registrations' final prices (which
+	 * should probably change because of this).
+	 * You should call EE_Registration_Processor::calculate_reg_final_prices_per_line_item()
+	 * after using this, to keep the registration final prices in-sync with the transaction's total.
+	 *
+	 * @param EE_Line_Item $total_line_item
+	 * @param EE_Line_Item $item to be added
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function add_item(EE_Line_Item $total_line_item, EE_Line_Item $item, $recalculate_totals = true)
+	{
+		$pre_tax_subtotal = self::get_pre_tax_subtotal($total_line_item);
+		if ($pre_tax_subtotal instanceof EE_Line_Item) {
+			$success = $pre_tax_subtotal->add_child_line_item($item);
+		} else {
+			return false;
+		}
+		if ($recalculate_totals) {
+			$total_line_item->recalculate_total_including_taxes();
+		}
+		return $success;
+	}
+
+
+	/**
+	 * cancels an existing ticket line item,
+	 * by decrementing it's quantity by 1 and adding a new "type_cancellation" sub-line-item.
+	 * ALL totals and subtotals will NEED TO BE UPDATED after performing this action
+	 *
+	 * @param EE_Line_Item $ticket_line_item
+	 * @param int          $qty
+	 * @return bool success
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function cancel_ticket_line_item(EE_Line_Item $ticket_line_item, $qty = 1)
+	{
+		// validate incoming line_item
+		if ($ticket_line_item->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_TICKET) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'The supplied line item must have an Object Type of "Ticket", not %1$s.',
+						'event_espresso'
+					),
+					$ticket_line_item->type()
+				)
+			);
+		}
+		if ($ticket_line_item->quantity() < $qty) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'Can not cancel %1$d ticket(s) because the supplied line item has a quantity of %2$d.',
+						'event_espresso'
+					),
+					$qty,
+					$ticket_line_item->quantity()
+				)
+			);
+		}
+		// decrement ticket quantity; don't rely on auto-fixing when recalculating totals to do this
+		$ticket_line_item->set_quantity($ticket_line_item->quantity() - $qty);
+		foreach ($ticket_line_item->children() as $child_line_item) {
+			if (
+				$child_line_item->is_sub_line_item()
+				&& ! $child_line_item->is_percent()
+				&& ! $child_line_item->is_cancellation()
+			) {
+				$child_line_item->set_quantity($child_line_item->quantity() - $qty);
+			}
+		}
+		// get cancellation sub line item
+		$cancellation_line_item = EEH_Line_Item::get_descendants_of_type(
+			$ticket_line_item,
+			EEM_Line_Item::type_cancellation
+		);
+		$cancellation_line_item = reset($cancellation_line_item);
+		// verify that this ticket was indeed previously cancelled
+		if ($cancellation_line_item instanceof EE_Line_Item) {
+			// increment cancelled quantity
+			$cancellation_line_item->set_quantity($cancellation_line_item->quantity() + $qty);
+		} else {
+			// create cancellation sub line item
+			$cancellation_line_item = EE_Line_Item::new_instance(array(
+				'LIN_name'       => esc_html__('Cancellation', 'event_espresso'),
+				'LIN_desc'       => sprintf(
+					esc_html_x(
+						'Cancelled %1$s : %2$s',
+						'Cancelled Ticket Name : 2015-01-01 11:11',
+						'event_espresso'
+					),
+					$ticket_line_item->name(),
+					current_time(get_option('date_format') . ' ' . get_option('time_format'))
+				),
+				'LIN_unit_price' => 0, // $ticket_line_item->unit_price()
+				'LIN_quantity'   => $qty,
+				'LIN_is_taxable' => $ticket_line_item->is_taxable(),
+				'LIN_order'      => count($ticket_line_item->children()),
+				'LIN_total'      => 0, // $ticket_line_item->unit_price()
+				'LIN_type'       => EEM_Line_Item::type_cancellation,
+			));
+			$ticket_line_item->add_child_line_item($cancellation_line_item);
+		}
+		if ($ticket_line_item->save_this_and_descendants() > 0) {
+			// decrement parent line item quantity
+			$event_line_item = $ticket_line_item->parent();
+			if (
+				$event_line_item instanceof EE_Line_Item
+				&& $event_line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_EVENT
+			) {
+				$event_line_item->set_quantity($event_line_item->quantity() - $qty);
+				$event_line_item->save();
+			}
+			EEH_Line_Item::get_grand_total_and_recalculate_everything($ticket_line_item);
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * reinstates (un-cancels?) a previously canceled ticket line item,
+	 * by incrementing it's quantity by 1, and decrementing it's "type_cancellation" sub-line-item.
+	 * ALL totals and subtotals will NEED TO BE UPDATED after performing this action
+	 *
+	 * @param EE_Line_Item $ticket_line_item
+	 * @param int          $qty
+	 * @return bool success
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function reinstate_canceled_ticket_line_item(EE_Line_Item $ticket_line_item, $qty = 1)
+	{
+		// validate incoming line_item
+		if ($ticket_line_item->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_TICKET) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'The supplied line item must have an Object Type of "Ticket", not %1$s.',
+						'event_espresso'
+					),
+					$ticket_line_item->type()
+				)
+			);
+		}
+		// get cancellation sub line item
+		$cancellation_line_item = EEH_Line_Item::get_descendants_of_type(
+			$ticket_line_item,
+			EEM_Line_Item::type_cancellation
+		);
+		$cancellation_line_item = reset($cancellation_line_item);
+		// verify that this ticket was indeed previously cancelled
+		if (! $cancellation_line_item instanceof EE_Line_Item) {
+			return false;
+		}
+		if ($cancellation_line_item->quantity() > $qty) {
+			// decrement cancelled quantity
+			$cancellation_line_item->set_quantity($cancellation_line_item->quantity() - $qty);
+		} elseif ($cancellation_line_item->quantity() === $qty) {
+			// decrement cancelled quantity in case anyone still has the object kicking around
+			$cancellation_line_item->set_quantity($cancellation_line_item->quantity() - $qty);
+			// delete because quantity will end up as 0
+			$cancellation_line_item->delete();
+			// and attempt to destroy the object,
+			// even though PHP won't actually destroy it until it needs the memory
+			unset($cancellation_line_item);
+		} else {
+			// what ?!?! negative quantity ?!?!
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'Can not reinstate %1$d cancelled ticket(s) because the cancelled ticket quantity is only %2$d.',
+						'event_espresso'
+					),
+					$qty,
+					$cancellation_line_item->quantity()
+				)
+			);
+		}
+		// increment ticket quantity
+		$ticket_line_item->set_quantity($ticket_line_item->quantity() + $qty);
+		if ($ticket_line_item->save_this_and_descendants() > 0) {
+			// increment parent line item quantity
+			$event_line_item = $ticket_line_item->parent();
+			if (
+				$event_line_item instanceof EE_Line_Item
+				&& $event_line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_EVENT
+			) {
+				$event_line_item->set_quantity($event_line_item->quantity() + $qty);
+			}
+			EEH_Line_Item::get_grand_total_and_recalculate_everything($ticket_line_item);
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * calls EEH_Line_Item::find_transaction_grand_total_for_line_item()
+	 * then EE_Line_Item::recalculate_total_including_taxes() on the result
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function get_grand_total_and_recalculate_everything(EE_Line_Item $line_item)
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($line_item);
+		return $grand_total_line_item->recalculate_total_including_taxes();
+	}
+
+
+	/**
+	 * Gets the line item which contains the subtotal of all the items
+	 *
+	 * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function get_pre_tax_subtotal(EE_Line_Item $total_line_item)
+	{
+		$pre_tax_subtotal = $total_line_item->get_child_line_item('pre-tax-subtotal');
+		return $pre_tax_subtotal instanceof EE_Line_Item
+			? $pre_tax_subtotal
+			: self::create_pre_tax_subtotal($total_line_item);
+	}
+
+
+	/**
+	 * Gets the line item for the taxes subtotal
+	 *
+	 * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function get_taxes_subtotal(EE_Line_Item $total_line_item)
+	{
+		$taxes = $total_line_item->get_child_line_item('taxes');
+		return $taxes ? $taxes : self::create_taxes_subtotal($total_line_item);
+	}
+
+
+	/**
+	 * sets the TXN ID on an EE_Line_Item if passed a valid EE_Transaction object
+	 *
+	 * @param EE_Line_Item   $line_item
+	 * @param EE_Transaction $transaction
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function set_TXN_ID(EE_Line_Item $line_item, $transaction = null)
+	{
+		if ($transaction) {
+			/** @type EEM_Transaction $EEM_Transaction */
+			$EEM_Transaction = EE_Registry::instance()->load_model('Transaction');
+			$TXN_ID = $EEM_Transaction->ensure_is_ID($transaction);
+			$line_item->set_TXN_ID($TXN_ID);
+		}
+	}
+
+
+	/**
+	 * Creates a new default total line item for the transaction,
+	 * and its tickets subtotal and taxes subtotal line items (and adds the
+	 * existing taxes as children of the taxes subtotal line item)
+	 *
+	 * @param EE_Transaction $transaction
+	 * @return EE_Line_Item of type total
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function create_total_line_item($transaction = null)
+	{
+		$total_line_item = EE_Line_Item::new_instance(array(
+			'LIN_code' => 'total',
+			'LIN_name' => esc_html__('Grand Total', 'event_espresso'),
+			'LIN_type' => EEM_Line_Item::type_total,
+			'OBJ_type' => EEM_Line_Item::OBJ_TYPE_TRANSACTION,
+		));
+		$total_line_item = apply_filters(
+			'FHEE__EEH_Line_Item__create_total_line_item__total_line_item',
+			$total_line_item
+		);
+		self::set_TXN_ID($total_line_item, $transaction);
+		self::create_pre_tax_subtotal($total_line_item, $transaction);
+		self::create_taxes_subtotal($total_line_item, $transaction);
+		return $total_line_item;
+	}
+
+
+	/**
+	 * Creates a default items subtotal line item
+	 *
+	 * @param EE_Line_Item   $total_line_item
+	 * @param EE_Transaction $transaction
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected static function create_pre_tax_subtotal(EE_Line_Item $total_line_item, $transaction = null)
+	{
+		$pre_tax_line_item = EE_Line_Item::new_instance(array(
+			'LIN_code' => 'pre-tax-subtotal',
+			'LIN_name' => esc_html__('Pre-Tax Subtotal', 'event_espresso'),
+			'LIN_type' => EEM_Line_Item::type_sub_total,
+		));
+		$pre_tax_line_item = apply_filters(
+			'FHEE__EEH_Line_Item__create_pre_tax_subtotal__pre_tax_line_item',
+			$pre_tax_line_item
+		);
+		self::set_TXN_ID($pre_tax_line_item, $transaction);
+		$total_line_item->add_child_line_item($pre_tax_line_item);
+		self::create_event_subtotal($pre_tax_line_item, $transaction);
+		return $pre_tax_line_item;
+	}
+
+
+	/**
+	 * Creates a line item for the taxes subtotal and finds all the tax prices
+	 * and applies taxes to it
+	 *
+	 * @param EE_Line_Item   $total_line_item of type EEM_Line_Item::type_total
+	 * @param EE_Transaction $transaction
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected static function create_taxes_subtotal(EE_Line_Item $total_line_item, $transaction = null)
+	{
+		$tax_line_item = EE_Line_Item::new_instance(array(
+			'LIN_code'  => 'taxes',
+			'LIN_name'  => esc_html__('Taxes', 'event_espresso'),
+			'LIN_type'  => EEM_Line_Item::type_tax_sub_total,
+			'LIN_order' => 1000,// this should always come last
+		));
+		$tax_line_item = apply_filters(
+			'FHEE__EEH_Line_Item__create_taxes_subtotal__tax_line_item',
+			$tax_line_item
+		);
+		self::set_TXN_ID($tax_line_item, $transaction);
+		$total_line_item->add_child_line_item($tax_line_item);
+		// and lastly, add the actual taxes
+		self::apply_taxes($total_line_item);
+		return $tax_line_item;
+	}
+
+
+	/**
+	 * Creates a default items subtotal line item
+	 *
+	 * @param EE_Line_Item   $pre_tax_line_item
+	 * @param EE_Transaction $transaction
+	 * @param EE_Event       $event
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function create_event_subtotal(EE_Line_Item $pre_tax_line_item, $transaction = null, $event = null)
+	{
+		$event_line_item = EE_Line_Item::new_instance(array(
+			'LIN_code' => self::get_event_code($event),
+			'LIN_name' => self::get_event_name($event),
+			'LIN_desc' => self::get_event_desc($event),
+			'LIN_type' => EEM_Line_Item::type_sub_total,
+			'OBJ_type' => EEM_Line_Item::OBJ_TYPE_EVENT,
+			'OBJ_ID'   => $event instanceof EE_Event ? $event->ID() : 0,
+		));
+		$event_line_item = apply_filters(
+			'FHEE__EEH_Line_Item__create_event_subtotal__event_line_item',
+			$event_line_item
+		);
+		self::set_TXN_ID($event_line_item, $transaction);
+		$pre_tax_line_item->add_child_line_item($event_line_item);
+		return $event_line_item;
+	}
+
+
+	/**
+	 * Gets what the event ticket's code SHOULD be
+	 *
+	 * @param EE_Event $event
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public static function get_event_code($event)
+	{
+		return 'event-' . ($event instanceof EE_Event ? $event->ID() : '0');
+	}
+
+
+	/**
+	 * Gets the event name
+	 *
+	 * @param EE_Event $event
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public static function get_event_name($event)
+	{
+		return $event instanceof EE_Event
+			? mb_substr($event->name(), 0, 245)
+			: esc_html__('Event', 'event_espresso');
+	}
+
+
+	/**
+	 * Gets the event excerpt
+	 *
+	 * @param EE_Event $event
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public static function get_event_desc($event)
+	{
+		return $event instanceof EE_Event ? $event->short_description() : '';
+	}
+
+
+	/**
+	 * Given the grand total line item and a ticket, finds the event sub-total
+	 * line item the ticket's purchase should be added onto
+	 *
+	 * @access public
+	 * @param EE_Line_Item $grand_total the grand total line item
+	 * @param EE_Ticket    $ticket
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function get_event_line_item_for_ticket(EE_Line_Item $grand_total, EE_Ticket $ticket)
+	{
+		$first_datetime = $ticket->first_datetime();
+		if (! $first_datetime instanceof EE_Datetime) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__('The supplied ticket (ID %d) has no datetimes', 'event_espresso'),
+					$ticket->ID()
+				)
+			);
+		}
+		$event = $first_datetime->event();
+		if (! $event instanceof EE_Event) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'The supplied ticket (ID %d) has no event data associated with it.',
+						'event_espresso'
+					),
+					$ticket->ID()
+				)
+			);
+		}
+		$events_sub_total = EEH_Line_Item::get_event_line_item($grand_total, $event);
+		if (! $events_sub_total instanceof EE_Line_Item) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'There is no events sub-total for ticket %s on total line item %d',
+						'event_espresso'
+					),
+					$ticket->ID(),
+					$grand_total->ID()
+				)
+			);
+		}
+		return $events_sub_total;
+	}
+
+
+	/**
+	 * Gets the event line item
+	 *
+	 * @param EE_Line_Item $grand_total
+	 * @param EE_Event     $event
+	 * @return EE_Line_Item for the event subtotal which is a child of $grand_total
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function get_event_line_item(EE_Line_Item $grand_total, $event)
+	{
+		/** @type EE_Event $event */
+		$event = EEM_Event::instance()->ensure_is_obj($event, true);
+		$event_line_item = null;
+		$found = false;
+		foreach (EEH_Line_Item::get_event_subtotals($grand_total) as $event_line_item) {
+			// default event subtotal, we should only ever find this the first time this method is called
+			if (! $event_line_item->OBJ_ID()) {
+				// let's use this! but first... set the event details
+				EEH_Line_Item::set_event_subtotal_details($event_line_item, $event);
+				$found = true;
+				break;
+			}
+			if ($event_line_item->OBJ_ID() === $event->ID()) {
+				// found existing line item for this event in the cart, so break out of loop and use this one
+				$found = true;
+				break;
+			}
+		}
+		if (! $found) {
+			// there is no event sub-total yet, so add it
+			$pre_tax_subtotal = EEH_Line_Item::get_pre_tax_subtotal($grand_total);
+			// create a new "event" subtotal below that
+			$event_line_item = EEH_Line_Item::create_event_subtotal($pre_tax_subtotal, null, $event);
+			// and set the event details
+			EEH_Line_Item::set_event_subtotal_details($event_line_item, $event);
+		}
+		return $event_line_item;
+	}
+
+
+	/**
+	 * Creates a default items subtotal line item
+	 *
+	 * @param EE_Line_Item   $event_line_item
+	 * @param EE_Event       $event
+	 * @param EE_Transaction $transaction
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function set_event_subtotal_details(
+		EE_Line_Item $event_line_item,
+		EE_Event $event,
+		$transaction = null
+	) {
+		if ($event instanceof EE_Event) {
+			$event_line_item->set_code(self::get_event_code($event));
+			$event_line_item->set_name(self::get_event_name($event));
+			$event_line_item->set_desc(self::get_event_desc($event));
+			$event_line_item->set_OBJ_ID($event->ID());
+		}
+		self::set_TXN_ID($event_line_item, $transaction);
+	}
+
+
+	/**
+	 * Finds what taxes should apply, adds them as tax line items under the taxes sub-total,
+	 * and recalculates the taxes sub-total and the grand total. Resets the taxes, so
+	 * any old taxes are removed
+	 *
+	 * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
+	 * @param bool         $update_txn_status
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	public static function apply_taxes(EE_Line_Item $total_line_item, $update_txn_status = false)
+	{
+		$total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($total_line_item);
+		$taxes_line_item = self::get_taxes_subtotal($total_line_item);
+		$existing_global_taxes = $taxes_line_item->tax_descendants();
+		$updates = false;
+		// loop thru taxes
+		$global_taxes = EEH_Line_Item::getGlobalTaxes();
+		foreach ($global_taxes as $order => $taxes) {
+			foreach ($taxes as $tax) {
+				if ($tax instanceof EE_Price) {
+					$found = false;
+					// check if this is already an existing tax
+					foreach ($existing_global_taxes as $existing_global_tax) {
+						if ($tax->ID() === $existing_global_tax->OBJ_ID()) {
+							// maybe update the tax rate in case it has changed
+							if ($existing_global_tax->percent() !== $tax->amount()) {
+								$existing_global_tax->set_percent($tax->amount());
+								$existing_global_tax->save();
+								$updates = true;
+							}
+							$found = true;
+							break;
+						}
+					}
+					if (! $found) {
+						// add a new line item for this global tax
+						$tax_line_item = apply_filters(
+							'FHEE__EEH_Line_Item__apply_taxes__tax_line_item',
+							EE_Line_Item::new_instance(
+								[
+									'LIN_name'       => $tax->name(),
+									'LIN_desc'       => $tax->desc(),
+									'LIN_percent'    => $tax->amount(),
+									'LIN_is_taxable' => false,
+									'LIN_order'      => $order,
+									'LIN_total'      => 0,
+									'LIN_type'       => EEM_Line_Item::type_tax,
+									'OBJ_type'       => EEM_Line_Item::OBJ_TYPE_PRICE,
+									'OBJ_ID'         => $tax->ID(),
+								]
+							)
+						);
+						$updates = $taxes_line_item->add_child_line_item($tax_line_item) ? true : $updates;
+					}
+				}
+			}
+		}
+		// only recalculate totals if something changed
+		if ($updates) {
+			$total_line_item->recalculate_total_including_taxes($update_txn_status);
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * Ensures that taxes have been applied to the order, if not applies them.
+	 * Returns the total amount of tax
+	 *
+	 * @param EE_Line_Item $total_line_item of type EEM_Line_Item::type_total
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function ensure_taxes_applied($total_line_item)
+	{
+		$taxes_subtotal = self::get_taxes_subtotal($total_line_item);
+		if (! $taxes_subtotal->children()) {
+			self::apply_taxes($total_line_item);
+		}
+		return $taxes_subtotal->total();
+	}
+
+
+	/**
+	 * Deletes ALL children of the passed line item
+	 *
+	 * @param EE_Line_Item $parent_line_item
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function delete_all_child_items(EE_Line_Item $parent_line_item)
+	{
+		$deleted = 0;
+		foreach ($parent_line_item->children() as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item) {
+				$deleted += EEH_Line_Item::delete_all_child_items($child_line_item);
+				if ($child_line_item->ID()) {
+					$child_line_item->delete();
+					unset($child_line_item);
+				} else {
+					$parent_line_item->delete_child_line_item($child_line_item->code());
+				}
+				$deleted++;
+			}
+		}
+		return $deleted;
+	}
+
+
+	/**
+	 * Deletes the line items as indicated by the line item code(s) provided,
+	 * regardless of where they're found in the line item tree. Automatically
+	 * re-calculates the line item totals and updates the related transaction. But
+	 * DOES NOT automatically upgrade the transaction's registrations' final prices (which
+	 * should probably change because of this).
+	 * You should call EE_Registration_Processor::calculate_reg_final_prices_per_line_item()
+	 * after using this, to keep the registration final prices in-sync with the transaction's total.
+	 *
+	 * @param EE_Line_Item      $total_line_item of type EEM_Line_Item::type_total
+	 * @param array|bool|string $line_item_codes
+	 * @return int number of items successfully removed
+	 * @throws EE_Error
+	 */
+	public static function delete_items(EE_Line_Item $total_line_item, $line_item_codes = false)
+	{
+
+		if ($total_line_item->type() !== EEM_Line_Item::type_total) {
+			EE_Error::doing_it_wrong(
+				'EEH_Line_Item::delete_items',
+				esc_html__(
+					'This static method should only be called with a TOTAL line item, otherwise we won\'t recalculate the totals correctly',
+					'event_espresso'
+				),
+				'4.6.18'
+			);
+		}
+		do_action('AHEE_log', __FILE__, __FUNCTION__, '');
+
+		// check if only a single line_item_id was passed
+		if (! empty($line_item_codes) && ! is_array($line_item_codes)) {
+			// place single line_item_id in an array to appear as multiple line_item_ids
+			$line_item_codes = array($line_item_codes);
+		}
+		$removals = 0;
+		// cycle thru line_item_ids
+		foreach ($line_item_codes as $line_item_id) {
+			$removals += $total_line_item->delete_child_line_item($line_item_id);
+		}
+
+		if ($removals > 0) {
+			$total_line_item->recalculate_taxes_and_tax_total();
+			return $removals;
+		} else {
+			return false;
+		}
+	}
+
+
+	/**
+	 * Overwrites the previous tax by clearing out the old taxes, and creates a new
+	 * tax and updates the total line item accordingly
+	 *
+	 * @param EE_Line_Item $total_line_item
+	 * @param float        $amount
+	 * @param string       $name
+	 * @param string       $description
+	 * @param string       $code
+	 * @param boolean      $add_to_existing_line_item
+	 *                          if true, and a duplicate line item with the same code is found,
+	 *                          $amount will be added onto it; otherwise will simply set the taxes to match $amount
+	 * @return EE_Line_Item the new tax line item created
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function set_total_tax_to(
+		EE_Line_Item $total_line_item,
+		$amount,
+		$name = null,
+		$description = null,
+		$code = null,
+		$add_to_existing_line_item = false
+	) {
+		$tax_subtotal = self::get_taxes_subtotal($total_line_item);
+		$taxable_total = $total_line_item->taxable_total();
+
+		if ($add_to_existing_line_item) {
+			$new_tax = $tax_subtotal->get_child_line_item($code);
+			EEM_Line_Item::instance()->delete(
+				array(array('LIN_code' => array('!=', $code), 'LIN_parent' => $tax_subtotal->ID()))
+			);
+		} else {
+			$new_tax = null;
+			$tax_subtotal->delete_children_line_items();
+		}
+		if ($new_tax) {
+			$new_tax->set_total($new_tax->total() + $amount);
+			$new_tax->set_percent($taxable_total ? $new_tax->total() / $taxable_total * 100 : 0);
+		} else {
+			// no existing tax item. Create it
+			$new_tax = EE_Line_Item::new_instance(array(
+				'TXN_ID'      => $total_line_item->TXN_ID(),
+				'LIN_name'    => $name ?: esc_html__('Tax', 'event_espresso'),
+				'LIN_desc'    => $description ?: '',
+				'LIN_percent' => $taxable_total ? ($amount / $taxable_total * 100) : 0,
+				'LIN_total'   => $amount,
+				'LIN_parent'  => $tax_subtotal->ID(),
+				'LIN_type'    => EEM_Line_Item::type_tax,
+				'LIN_code'    => $code,
+			));
+		}
+
+		$new_tax = apply_filters(
+			'FHEE__EEH_Line_Item__set_total_tax_to__new_tax_subtotal',
+			$new_tax,
+			$total_line_item
+		);
+		$new_tax->save();
+		$tax_subtotal->set_total($new_tax->total());
+		$tax_subtotal->save();
+		$total_line_item->recalculate_total_including_taxes();
+		return $new_tax;
+	}
+
+
+	/**
+	 * Makes all the line items which are children of $line_item taxable (or not).
+	 * Does NOT save the line items
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @param boolean      $taxable
+	 * @param string       $code_substring_for_whitelist if this string is part of the line item's code
+	 *                                                   it will be whitelisted (ie, except from becoming taxable)
+	 * @throws EE_Error
+	 */
+	public static function set_line_items_taxable(
+		EE_Line_Item $line_item,
+		$taxable = true,
+		$code_substring_for_whitelist = null
+	) {
+		$whitelisted = false;
+		if ($code_substring_for_whitelist !== null) {
+			$whitelisted = strpos($line_item->code(), $code_substring_for_whitelist) !== false;
+		}
+		if (! $whitelisted && $line_item->is_line_item()) {
+			$line_item->set_is_taxable($taxable);
+		}
+		foreach ($line_item->children() as $child_line_item) {
+			EEH_Line_Item::set_line_items_taxable(
+				$child_line_item,
+				$taxable,
+				$code_substring_for_whitelist
+			);
+		}
+	}
+
+
+	/**
+	 * Gets all descendants that are event subtotals
+	 *
+	 * @uses  EEH_Line_Item::get_subtotals_of_object_type()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public static function get_event_subtotals(EE_Line_Item $parent_line_item)
+	{
+		return self::get_subtotals_of_object_type($parent_line_item, EEM_Line_Item::OBJ_TYPE_EVENT);
+	}
+
+
+	/**
+	 * Gets all descendants subtotals that match the supplied object type
+	 *
+	 * @uses  EEH_Line_Item::_get_descendants_by_type_and_object_type()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @param string       $obj_type
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public static function get_subtotals_of_object_type(EE_Line_Item $parent_line_item, $obj_type = '')
+	{
+		return self::_get_descendants_by_type_and_object_type(
+			$parent_line_item,
+			EEM_Line_Item::type_sub_total,
+			$obj_type
+		);
+	}
+
+
+	/**
+	 * Gets all descendants that are tickets
+	 *
+	 * @uses  EEH_Line_Item::get_line_items_of_object_type()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public static function get_ticket_line_items(EE_Line_Item $parent_line_item)
+	{
+		return self::get_line_items_of_object_type(
+			$parent_line_item,
+			EEM_Line_Item::OBJ_TYPE_TICKET
+		);
+	}
+
+
+	/**
+	 * Gets all descendants subtotals that match the supplied object type
+	 *
+	 * @uses  EEH_Line_Item::_get_descendants_by_type_and_object_type()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @param string       $obj_type
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public static function get_line_items_of_object_type(EE_Line_Item $parent_line_item, $obj_type = '')
+	{
+		return self::_get_descendants_by_type_and_object_type(
+			$parent_line_item,
+			EEM_Line_Item::type_line_item,
+			$obj_type
+		);
+	}
+
+
+	/**
+	 * Gets all the descendants (ie, children or children of children etc) that are of the type 'tax'
+	 *
+	 * @uses  EEH_Line_Item::get_descendants_of_type()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public static function get_tax_descendants(EE_Line_Item $parent_line_item)
+	{
+		return EEH_Line_Item::get_descendants_of_type(
+			$parent_line_item,
+			EEM_Line_Item::type_tax
+		);
+	}
+
+
+	/**
+	 * Gets all the real items purchased which are children of this item
+	 *
+	 * @uses  EEH_Line_Item::get_descendants_of_type()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public static function get_line_item_descendants(EE_Line_Item $parent_line_item)
+	{
+		return EEH_Line_Item::get_descendants_of_type(
+			$parent_line_item,
+			EEM_Line_Item::type_line_item
+		);
+	}
+
+
+	/**
+	 * Gets all descendants of supplied line item that match the supplied line item type
+	 *
+	 * @uses  EEH_Line_Item::_get_descendants_by_type_and_object_type()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @param string       $line_item_type   one of the EEM_Line_Item constants
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public static function get_descendants_of_type(EE_Line_Item $parent_line_item, $line_item_type)
+	{
+		return self::_get_descendants_by_type_and_object_type(
+			$parent_line_item,
+			$line_item_type,
+			null
+		);
+	}
+
+
+	/**
+	 * Gets all descendants of supplied line item that match the supplied line item type and possibly the object type
+	 * as well
+	 *
+	 * @param EE_Line_Item  $parent_line_item - the line item to find descendants of
+	 * @param string        $line_item_type   one of the EEM_Line_Item constants
+	 * @param string | NULL $obj_type         object model class name (minus prefix) or NULL to ignore object type when
+	 *                                        searching
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	protected static function _get_descendants_by_type_and_object_type(
+		EE_Line_Item $parent_line_item,
+		$line_item_type,
+		$obj_type = null
+	) {
+		$objects = array();
+		foreach ($parent_line_item->children() as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item) {
+				if (
+					$child_line_item->type() === $line_item_type
+					&& (
+						$child_line_item->OBJ_type() === $obj_type || $obj_type === null
+					)
+				) {
+					$objects[] = $child_line_item;
+				} else {
+					// go-through-all-its children looking for more matches
+					$objects = array_merge(
+						$objects,
+						self::_get_descendants_by_type_and_object_type(
+							$child_line_item,
+							$line_item_type,
+							$obj_type
+						)
+					);
+				}
+			}
+		}
+		return $objects;
+	}
+
+
+	/**
+	 * Gets all descendants subtotals that match the supplied object type
+	 *
+	 * @uses  EEH_Line_Item::_get_descendants_by_type_and_object_type()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @param string       $OBJ_type         object type (like Event)
+	 * @param array        $OBJ_IDs          array of OBJ_IDs
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public static function get_line_items_by_object_type_and_IDs(
+		EE_Line_Item $parent_line_item,
+		$OBJ_type = '',
+		$OBJ_IDs = array()
+	) {
+		return self::_get_descendants_by_object_type_and_object_ID(
+			$parent_line_item,
+			$OBJ_type,
+			$OBJ_IDs
+		);
+	}
+
+
+	/**
+	 * Gets all descendants of supplied line item that match the supplied line item type and possibly the object type
+	 * as well
+	 *
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @param string       $OBJ_type         object type (like Event)
+	 * @param array        $OBJ_IDs          array of OBJ_IDs
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	protected static function _get_descendants_by_object_type_and_object_ID(
+		EE_Line_Item $parent_line_item,
+		$OBJ_type,
+		$OBJ_IDs
+	) {
+		$objects = array();
+		foreach ($parent_line_item->children() as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item) {
+				if (
+					$child_line_item->OBJ_type() === $OBJ_type
+					&& is_array($OBJ_IDs)
+					&& in_array($child_line_item->OBJ_ID(), $OBJ_IDs)
+				) {
+					$objects[] = $child_line_item;
+				} else {
+					// go-through-all-its children looking for more matches
+					$objects = array_merge(
+						$objects,
+						self::_get_descendants_by_object_type_and_object_ID(
+							$child_line_item,
+							$OBJ_type,
+							$OBJ_IDs
+						)
+					);
+				}
+			}
+		}
+		return $objects;
+	}
+
+
+	/**
+	 * Uses a breadth-first-search in order to find the nearest descendant of
+	 * the specified type and returns it, else NULL
+	 *
+	 * @uses  EEH_Line_Item::_get_nearest_descendant()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @param string       $type             like one of the EEM_Line_Item::type_*
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function get_nearest_descendant_of_type(EE_Line_Item $parent_line_item, $type)
+	{
+		return self::_get_nearest_descendant($parent_line_item, 'LIN_type', $type);
+	}
+
+
+	/**
+	 * Uses a breadth-first-search in order to find the nearest descendant
+	 * having the specified LIN_code and returns it, else NULL
+	 *
+	 * @uses  EEH_Line_Item::_get_nearest_descendant()
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @param string       $code             any value used for LIN_code
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function get_nearest_descendant_having_code(EE_Line_Item $parent_line_item, $code)
+	{
+		return self::_get_nearest_descendant($parent_line_item, 'LIN_code', $code);
+	}
+
+
+	/**
+	 * Uses a breadth-first-search in order to find the nearest descendant
+	 * having the specified LIN_code and returns it, else NULL
+	 *
+	 * @param EE_Line_Item $parent_line_item - the line item to find descendants of
+	 * @param string       $search_field     name of EE_Line_Item property
+	 * @param string       $value            any value stored in $search_field
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected static function _get_nearest_descendant(EE_Line_Item $parent_line_item, $search_field, $value)
+	{
+		foreach ($parent_line_item->children() as $child) {
+			if ($child->get($search_field) == $value) {
+				return $child;
+			}
+		}
+		foreach ($parent_line_item->children() as $child) {
+			$descendant_found = self::_get_nearest_descendant(
+				$child,
+				$search_field,
+				$value
+			);
+			if ($descendant_found) {
+				return $descendant_found;
+			}
+		}
+		return null;
+	}
+
+
+	/**
+	 * if passed line item has a TXN ID, uses that to jump directly to the grand total line item for the transaction,
+	 * else recursively walks up the line item tree until a parent of type total is found,
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function find_transaction_grand_total_for_line_item(EE_Line_Item $line_item): EE_Line_Item
+	{
+		if ($line_item->is_total()) {
+			return $line_item;
+		}
+		if ($line_item->TXN_ID()) {
+			$total_line_item = $line_item->transaction()->total_line_item(false);
+			if ($total_line_item instanceof EE_Line_Item) {
+				return $total_line_item;
+			}
+		} else {
+			$line_item_parent = $line_item->parent();
+			if ($line_item_parent instanceof EE_Line_Item) {
+				if ($line_item_parent->is_total()) {
+					return $line_item_parent;
+				}
+				return EEH_Line_Item::find_transaction_grand_total_for_line_item($line_item_parent);
+			}
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					'A valid grand total for line item %1$d was not found.',
+					'event_espresso'
+				),
+				$line_item->ID()
+			)
+		);
+	}
+
+
+	/**
+	 * Prints out a representation of the line item tree
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @param int          $indentation
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public static function visualize(EE_Line_Item $line_item, $indentation = 0)
+	{
+		$new_line = defined('EE_TESTS_DIR') ? "\n" : '<br />';
+		echo $new_line;
+		if (! $indentation) {
+			echo $new_line;
+		}
+		echo str_repeat('. ', $indentation);
+		$breakdown = '';
+		if ($line_item->is_line_item() || $line_item->is_sub_line_item() || $line_item->isSubTax()) {
+			if ($line_item->is_percent()) {
+				$breakdown = "{$line_item->percent()}%";
+			} else {
+				$breakdown = "\${$line_item->unit_price()} x {$line_item->quantity()}";
+			}
+		}
+		echo wp_kses($line_item->name(), AllowedTags::getAllowedTags());
+		echo " [ ID:{$line_item->ID()} | qty:{$line_item->quantity()} ] {$line_item->type()} : ";
+		echo "\${$line_item->total()}";
+		if ($breakdown) {
+			echo " ( {$breakdown} )";
+		}
+		if ($line_item->is_taxable()) {
+			echo '  * taxable';
+		}
+		if ($line_item->children()) {
+			foreach ($line_item->children() as $child) {
+				self::visualize($child, $indentation + 1);
+			}
+		}
+		if (! $indentation) {
+			echo $new_line . $new_line;
+		}
+	}
+
+
+	/**
+	 * Calculates the registration's final price, taking into account that they
+	 * need to not only help pay for their OWN ticket, but also any transaction-wide surcharges and taxes,
+	 * and receive a portion of any transaction-wide discounts.
+	 * eg1, if I buy a $1 ticket and brent buys a $9 ticket, and we receive a $5 discount
+	 * then I'll get 1/10 of that $5 discount, which is $0.50, and brent will get
+	 * 9/10ths of that $5 discount, which is $4.50. So my final price should be $0.50
+	 * and brent's final price should be $5.50.
+	 * In order to do this, we basically need to traverse the line item tree calculating
+	 * the running totals (just as if we were recalculating the total), but when we identify
+	 * regular line items, we need to keep track of their share of the grand total.
+	 * Also, we need to keep track of the TAXABLE total for each ticket purchase, so
+	 * we can know how to apply taxes to it. (Note: "taxable total" does not equal the "pretax total"
+	 * when there are non-taxable items; otherwise they would be the same)
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @param array        $billable_ticket_quantities  array of EE_Ticket IDs and their corresponding quantity that
+	 *                                                  can be included in price calculations at this moment
+	 * @return array        keys are line items for tickets IDs and values are their share of the running total,
+	 *                                                  plus the key 'total', and 'taxable' which also has keys of all
+	 *                                                  the ticket IDs.
+	 *                                                  Eg array(
+	 *                                                      12 => 4.3
+	 *                                                      23 => 8.0
+	 *                                                      'total' => 16.6,
+	 *                                                      'taxable' => array(
+	 *                                                          12 => 10,
+	 *                                                          23 => 4
+	 *                                                      ).
+	 *                                                  So to find which registrations have which final price, we need
+	 *                                                  to find which line item is theirs, which can be done with
+	 *                                                  `EEM_Line_Item::instance()->get_line_item_for_registration(
+	 *                                                  $registration );`
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function calculate_reg_final_prices_per_line_item(
+		EE_Line_Item $line_item,
+		$billable_ticket_quantities = array()
+	) {
+		$running_totals = [
+			'total'   => 0,
+			'taxable' => ['total' => 0]
+		];
+		foreach ($line_item->children() as $child_line_item) {
+			switch ($child_line_item->type()) {
+				case EEM_Line_Item::type_sub_total:
+					$running_totals_from_subtotal = EEH_Line_Item::calculate_reg_final_prices_per_line_item(
+						$child_line_item,
+						$billable_ticket_quantities
+					);
+					// combine arrays but preserve numeric keys
+					$running_totals = array_replace_recursive($running_totals_from_subtotal, $running_totals);
+					$running_totals['total'] += $running_totals_from_subtotal['total'];
+					$running_totals['taxable']['total'] += $running_totals_from_subtotal['taxable']['total'];
+					break;
+
+				case EEM_Line_Item::type_tax_sub_total:
+					// find how much the taxes percentage is
+					if ($child_line_item->percent() !== 0) {
+						$tax_percent_decimal = $child_line_item->percent() / 100;
+					} else {
+						$tax_percent_decimal = EE_Taxes::get_total_taxes_percentage() / 100;
+					}
+					// and apply to all the taxable totals, and add to the pretax totals
+					foreach ($running_totals as $line_item_id => $this_running_total) {
+						// "total" and "taxable" array key is an exception
+						if ($line_item_id === 'taxable') {
+							continue;
+						}
+						$taxable_total = $running_totals['taxable'][ $line_item_id ];
+						$running_totals[ $line_item_id ] += ($taxable_total * $tax_percent_decimal);
+					}
+					break;
+
+				case EEM_Line_Item::type_line_item:
+					// ticket line items or ????
+					if ($child_line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET) {
+						// kk it's a ticket
+						if (isset($running_totals[ $child_line_item->ID() ])) {
+							// huh? that shouldn't happen.
+							$running_totals['total'] += $child_line_item->total();
+						} else {
+							// its not in our running totals yet. great.
+							if ($child_line_item->is_taxable()) {
+								$taxable_amount = $child_line_item->unit_price();
+							} else {
+								$taxable_amount = 0;
+							}
+							// are we only calculating totals for some tickets?
+							if (isset($billable_ticket_quantities[ $child_line_item->OBJ_ID() ])) {
+								$quantity = $billable_ticket_quantities[ $child_line_item->OBJ_ID() ];
+								$running_totals[ $child_line_item->ID() ] = $quantity
+									? $child_line_item->unit_price()
+									: 0;
+								$running_totals['taxable'][ $child_line_item->ID() ] = $quantity
+									? $taxable_amount
+									: 0;
+							} else {
+								$quantity = $child_line_item->quantity();
+								$running_totals[ $child_line_item->ID() ] = $child_line_item->unit_price();
+								$running_totals['taxable'][ $child_line_item->ID() ] = $taxable_amount;
+							}
+							$running_totals['taxable']['total'] += $taxable_amount * $quantity;
+							$running_totals['total'] += $child_line_item->unit_price() * $quantity;
+						}
+					} else {
+						// it's some other type of item added to the cart
+						// it should affect the running totals
+						// basically we want to convert it into a PERCENT modifier. Because
+						// more clearly affect all registration's final price equally
+						$line_items_percent_of_running_total = $running_totals['total'] > 0
+							? ($child_line_item->total() / $running_totals['total']) + 1
+							: 1;
+						foreach ($running_totals as $line_item_id => $this_running_total) {
+							// the "taxable" array key is an exception
+							if ($line_item_id === 'taxable') {
+								continue;
+							}
+							// update the running totals
+							// yes this actually even works for the running grand total!
+							$running_totals[ $line_item_id ] =
+								$line_items_percent_of_running_total * $this_running_total;
+
+							if ($child_line_item->is_taxable()) {
+								$running_totals['taxable'][ $line_item_id ] =
+									$line_items_percent_of_running_total * $running_totals['taxable'][ $line_item_id ];
+							}
+						}
+					}
+					break;
+			}
+		}
+		return $running_totals;
+	}
+
+
+	/**
+	 * @param EE_Line_Item $total_line_item
+	 * @param EE_Line_Item $ticket_line_item
+	 * @return float | null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws OutOfRangeException
+	 * @throws ReflectionException
+	 */
+	public static function calculate_final_price_for_ticket_line_item(
+		EE_Line_Item $total_line_item,
+		EE_Line_Item $ticket_line_item
+	) {
+		static $final_prices_per_ticket_line_item = array();
+		if (empty($final_prices_per_ticket_line_item) || empty($final_prices_per_ticket_line_item[ $total_line_item->ID() ])) {
+			$final_prices_per_ticket_line_item[ $total_line_item->ID() ] = EEH_Line_Item::calculate_reg_final_prices_per_line_item(
+				$total_line_item
+			);
+		}
+		// ok now find this new registration's final price
+		if (isset($final_prices_per_ticket_line_item[ $total_line_item->ID() ][ $ticket_line_item->ID() ])) {
+			return $final_prices_per_ticket_line_item[ $total_line_item->ID() ][ $ticket_line_item->ID() ];
+		}
+		$message = sprintf(
+			esc_html__(
+				'The final price for the ticket line item (ID:%1$d) on the total line item (ID:%2$d) could not be calculated.',
+				'event_espresso'
+			),
+			$ticket_line_item->ID(),
+			$total_line_item->ID()
+		);
+		if (WP_DEBUG) {
+			$message .= '<br>' . print_r($final_prices_per_ticket_line_item, true);
+			throw new OutOfRangeException($message);
+		}
+		EE_Log::instance()->log(__CLASS__, __FUNCTION__, $message);
+		return null;
+	}
+
+
+	/**
+	 * Creates a duplicate of the line item tree, except only includes billable items
+	 * and the portion of line items attributed to billable things
+	 *
+	 * @param EE_Line_Item      $line_item
+	 * @param EE_Registration[] $registrations
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function billable_line_item_tree(EE_Line_Item $line_item, $registrations)
+	{
+		$copy_li = EEH_Line_Item::billable_line_item($line_item, $registrations);
+		foreach ($line_item->children() as $child_li) {
+			$copy_li->add_child_line_item(
+				EEH_Line_Item::billable_line_item_tree($child_li, $registrations)
+			);
+		}
+		// if this is the grand total line item, make sure the totals all add up
+		// (we could have duplicated this logic AS we copied the line items, but
+		// it seems DRYer this way)
+		if ($copy_li->type() === EEM_Line_Item::type_total) {
+			$copy_li->recalculate_total_including_taxes();
+		}
+		return $copy_li;
+	}
+
+
+	/**
+	 * Creates a new, unsaved line item from $line_item that factors in the
+	 * number of billable registrations on $registrations.
+	 *
+	 * @param EE_Line_Item      $line_item
+	 * @param EE_Registration[] $registrations
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function billable_line_item(EE_Line_Item $line_item, $registrations)
+	{
+		$new_li_fields = $line_item->model_field_array();
+		if (
+			$line_item->type() === EEM_Line_Item::type_line_item &&
+			$line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET
+		) {
+			$count = 0;
+			foreach ($registrations as $registration) {
+				if (
+					$line_item->OBJ_ID() === $registration->ticket_ID() &&
+					in_array(
+						$registration->status_ID(),
+						EEM_Registration::reg_statuses_that_allow_payment(),
+						true
+					)
+				) {
+					$count++;
+				}
+			}
+			$new_li_fields['LIN_quantity'] = $count;
+		}
+		// don't set the total. We'll leave that up to the code that calculates it
+		unset($new_li_fields['LIN_ID'], $new_li_fields['LIN_parent'], $new_li_fields['LIN_total']);
+		return EE_Line_Item::new_instance($new_li_fields);
+	}
+
+
+	/**
+	 * Returns a modified line item tree where all the subtotals which have a total of 0
+	 * are removed, and line items with a quantity of 0
+	 *
+	 * @param EE_Line_Item $line_item |null
+	 * @return EE_Line_Item|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function non_empty_line_items(EE_Line_Item $line_item)
+	{
+		$copied_li = EEH_Line_Item::non_empty_line_item($line_item);
+		if ($copied_li === null) {
+			return null;
+		}
+		// if this is an event subtotal, we want to only include it if it
+		// has a non-zero total and at least one ticket line item child
+		$ticket_children = 0;
+		foreach ($line_item->children() as $child_li) {
+			$child_li_copy = EEH_Line_Item::non_empty_line_items($child_li);
+			if ($child_li_copy !== null) {
+				$copied_li->add_child_line_item($child_li_copy);
+				if (
+					$child_li_copy->type() === EEM_Line_Item::type_line_item &&
+					$child_li_copy->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET
+				) {
+					$ticket_children++;
+				}
+			}
+		}
+		// if this is an event subtotal with NO ticket children
+		// we basically want to ignore it
+		if (
+			$ticket_children === 0
+			&& $line_item->type() === EEM_Line_Item::type_sub_total
+			&& $line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_EVENT
+			&& $line_item->total() === 0
+		) {
+			return null;
+		}
+		return $copied_li;
+	}
+
+
+	/**
+	 * Creates a new, unsaved line item, but if it's a ticket line item
+	 * with a total of 0, or a subtotal of 0, returns null instead
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function non_empty_line_item(EE_Line_Item $line_item)
+	{
+		if (
+			$line_item->type() === EEM_Line_Item::type_line_item
+			&& $line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET
+			&& $line_item->quantity() === 0
+		) {
+			return null;
+		}
+		$new_li_fields = $line_item->model_field_array();
+		// don't set the total. We'll leave that up to the code that calculates it
+		unset($new_li_fields['LIN_ID'], $new_li_fields['LIN_parent']);
+		return EE_Line_Item::new_instance($new_li_fields);
+	}
+
+
+	/**
+	 * Cycles through all of the ticket line items for the supplied total line item
+	 * and ensures that the line item's "is_taxable" field matches that of its corresponding ticket
+	 *
+	 * @param EE_Line_Item $total_line_item
+	 * @since 4.9.79.p
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function resetIsTaxableForTickets(EE_Line_Item $total_line_item)
+	{
+		$ticket_line_items = self::get_ticket_line_items($total_line_item);
+		foreach ($ticket_line_items as $ticket_line_item) {
+			if (
+				$ticket_line_item instanceof EE_Line_Item
+				&& $ticket_line_item->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET
+			) {
+				$ticket = $ticket_line_item->ticket();
+				if ($ticket instanceof EE_Ticket && $ticket->taxable() !== $ticket_line_item->is_taxable()) {
+					$ticket_line_item->set_is_taxable($ticket->taxable());
+					$ticket_line_item->save();
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since   $VID:$
+	 */
+	private static function getGlobalTaxes(): array
+	{
+		if (EEH_Line_Item::$global_taxes === null) {
+
+			/** @type EEM_Price $EEM_Price */
+			$EEM_Price = EE_Registry::instance()->load_model('Price');
+			// get array of taxes via Price Model
+			EEH_Line_Item::$global_taxes = $EEM_Price->get_all_prices_that_are_taxes();
+			ksort(EEH_Line_Item::$global_taxes);
+		}
+		return EEH_Line_Item::$global_taxes;
+	}
+
+
+
+	/**************************************** @DEPRECATED METHODS *************************************** */
+	/**
+	 * @deprecated
+	 * @param EE_Line_Item $total_line_item
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function get_items_subtotal(EE_Line_Item $total_line_item)
+	{
+		EE_Error::doing_it_wrong(
+			'EEH_Line_Item::get_items_subtotal()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::get_pre_tax_subtotal()'
+			),
+			'4.6.0'
+		);
+		return self::get_pre_tax_subtotal($total_line_item);
+	}
+
+
+	/**
+	 * @deprecated
+	 * @param EE_Transaction $transaction
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function create_default_total_line_item($transaction = null)
+	{
+		EE_Error::doing_it_wrong(
+			'EEH_Line_Item::create_default_total_line_item()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::create_total_line_item()'
+			),
+			'4.6.0'
+		);
+		return self::create_total_line_item($transaction);
+	}
+
+
+	/**
+	 * @deprecated
+	 * @param EE_Line_Item   $total_line_item
+	 * @param EE_Transaction $transaction
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function create_default_tickets_subtotal(EE_Line_Item $total_line_item, $transaction = null)
+	{
+		EE_Error::doing_it_wrong(
+			'EEH_Line_Item::create_default_tickets_subtotal()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::create_pre_tax_subtotal()'
+			),
+			'4.6.0'
+		);
+		return self::create_pre_tax_subtotal($total_line_item, $transaction);
+	}
+
+
+	/**
+	 * @deprecated
+	 * @param EE_Line_Item   $total_line_item
+	 * @param EE_Transaction $transaction
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function create_default_taxes_subtotal(EE_Line_Item $total_line_item, $transaction = null)
+	{
+		EE_Error::doing_it_wrong(
+			'EEH_Line_Item::create_default_taxes_subtotal()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::create_taxes_subtotal()'
+			),
+			'4.6.0'
+		);
+		return self::create_taxes_subtotal($total_line_item, $transaction);
+	}
+
+
+	/**
+	 * @deprecated
+	 * @param EE_Line_Item   $total_line_item
+	 * @param EE_Transaction $transaction
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function create_default_event_subtotal(EE_Line_Item $total_line_item, $transaction = null)
+	{
+		EE_Error::doing_it_wrong(
+			'EEH_Line_Item::create_default_event_subtotal()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::create_event_subtotal()'
+			),
+			'4.6.0'
+		);
+		return self::create_event_subtotal($total_line_item, $transaction);
+	}
 }

core/admin/EE_Admin_Page_Menu_Map.core.php

Indentation +45 added lines, -45 removed lines

@@ -12,49 +12,49 @@
  */
 abstract class EE_Admin_Page_Menu_Map extends AdminMenuItem
 {
-    const NONE                   = 0;
-
-    const BLOG_ADMIN_ONLY        = 1;
-
-    const BLOG_AND_NETWORK_ADMIN = 2;
-
-    const NETWORK_ADMIN_ONLY     = 3;
-
-
-    /**
-     * @return string
-     * @deprecated $VID:$
-     */
-    protected function _add_menu_page(): string
-    {
-        return $this->registerMenuItem();
-    }
-
-
-    /**
-     * @param boolean $network_admin whether this is being added to the network admin page or not
-     * @deprecated $VID:$
-     * @since  4.4.0
-     */
-    public function add_menu_page(bool $network_admin = false)
-    {
-        $this->registerAdminMenuItem($network_admin);
-    }
-
-
-    public function __get(string $property)
-    {
-        // converts a property name like 'menu_slug' into 'menuSlug'
-        $getter = lcfirst(ucwords($property, '_'));
-        return method_exists($this, $getter) ? $this->{$getter}() : null;
-    }
-
-    public function __set(string $property, $value)
-    {
-        // converts a property name like 'menu_slug' into 'setMenuSlug'
-        $setter = 'set' . ucwords($property, '_');
-        if (method_exists($this, $setter)) {
-            $this->{$setter}($value);
-        }
-    }
+	const NONE                   = 0;
+
+	const BLOG_ADMIN_ONLY        = 1;
+
+	const BLOG_AND_NETWORK_ADMIN = 2;
+
+	const NETWORK_ADMIN_ONLY     = 3;
+
+
+	/**
+	 * @return string
+	 * @deprecated $VID:$
+	 */
+	protected function _add_menu_page(): string
+	{
+		return $this->registerMenuItem();
+	}
+
+
+	/**
+	 * @param boolean $network_admin whether this is being added to the network admin page or not
+	 * @deprecated $VID:$
+	 * @since  4.4.0
+	 */
+	public function add_menu_page(bool $network_admin = false)
+	{
+		$this->registerAdminMenuItem($network_admin);
+	}
+
+
+	public function __get(string $property)
+	{
+		// converts a property name like 'menu_slug' into 'menuSlug'
+		$getter = lcfirst(ucwords($property, '_'));
+		return method_exists($this, $getter) ? $this->{$getter}() : null;
+	}
+
+	public function __set(string $property, $value)
+	{
+		// converts a property name like 'menu_slug' into 'setMenuSlug'
+		$setter = 'set' . ucwords($property, '_');
+		if (method_exists($this, $setter)) {
+			$this->{$setter}($value);
+		}
+	}
 }

core/services/request/Request.php

Indentation +549 added lines, -549 removed lines

@@ -16,553 +16,553 @@
  */
 class Request implements InterminableInterface, RequestInterface, ReservedInstanceInterface
 {
-    /**
-     * $_COOKIE parameters
-     *
-     * @var array
-     */
-    protected $cookies;
-
-    /**
-     * $_FILES parameters
-     *
-     * @var array
-     */
-    protected $files;
-
-    /**
-     * true if current user appears to be some kind of bot
-     *
-     * @var bool
-     */
-    protected $is_bot;
-
-    /**
-     * @var RequestParams
-     */
-    protected $request_params;
-
-    /**
-     * @var RequestTypeContextCheckerInterface
-     */
-    protected $request_type;
-
-    /**
-     * @var ServerParams
-     */
-    protected $server_params;
-
-
-    public function __construct(
-        RequestParams $request_params,
-        ServerParams $server_params,
-        array $cookies = [],
-        array $files = []
-    ) {
-        $this->cookies        = ! empty($cookies)
-            ? $cookies
-            : filter_input_array(INPUT_COOKIE, FILTER_UNSAFE_RAW);
-        $this->files          = ! empty($files) ? $files : $_FILES;
-        $this->request_params = $request_params;
-        $this->server_params  = $server_params;
-    }
-
-
-    /**
-     * @param RequestTypeContextCheckerInterface $type
-     */
-    public function setRequestTypeContextChecker(RequestTypeContextCheckerInterface $type)
-    {
-        $this->request_type = $type;
-    }
-
-
-    /**
-     * @return array
-     */
-    public function getParams()
-    {
-        return $this->request_params->getParams();
-    }
-
-
-    /**
-     * @return array
-     */
-    public function postParams()
-    {
-        return $this->request_params->postParams();
-    }
-
-
-    /**
-     * @return array
-     */
-    public function cookieParams()
-    {
-        return $this->cookies;
-    }
-
-
-    /**
-     * @return array
-     */
-    public function serverParams()
-    {
-        return $this->server_params->getAllServerParams();
-    }
-
-
-    /**
-     * @param string     $key
-     * @param mixed|null $default
-     * @return array|int|float|string
-     */
-    public function getServerParam($key, $default = null)
-    {
-        return $this->server_params->getServerParam($key, $default);
-    }
-
-
-    /**
-     * @param string                 $key
-     * @param array|int|float|string $value
-     * @param bool                   $set_global_too
-     * @return void
-     */
-    public function setServerParam(string $key, $value, bool $set_global_too = false)
-    {
-        $this->server_params->setServerParam($key, $value, $set_global_too);
-    }
-
-
-    /**
-     * @param string $key
-     * @return bool
-     */
-    public function serverParamIsSet($key)
-    {
-        return $this->server_params->serverParamIsSet($key);
-    }
-
-
-    /**
-     * @return array
-     */
-    public function filesParams()
-    {
-        return $this->files;
-    }
-
-
-    /**
-     * returns sanitized contents of $_REQUEST
-     *
-     * @return array
-     */
-    public function requestParams()
-    {
-        return $this->request_params->requestParams();
-    }
-
-
-    /**
-     * @param string     $key
-     * @param mixed|null $value
-     * @param bool       $override_ee
-     * @return void
-     */
-    public function setRequestParam($key, $value, $override_ee = false)
-    {
-        $this->request_params->setRequestParam($key, $value, $override_ee);
-    }
-
-
-    /**
-     * merges the incoming array of parameters into the existing request parameters
-     *
-     * @param array $request_params
-     * @return void
-     * @since   4.10.24.p
-     */
-    public function mergeRequestParams(array $request_params)
-    {
-        $this->request_params->mergeRequestParams($request_params);
-    }
-
-
-    /**
-     * returns sanitized value for a request param if the given key exists
-     *
-     * @param string     $key
-     * @param mixed|null $default
-     * @param string     $type      the expected data type for the parameter's value, ie: string, int, bool, etc
-     * @param bool       $is_array  if true, then parameter value will be treated as an array of $type
-     * @param string     $delimiter for CSV type strings that should be returned as an array
-     * @return array|bool|float|int|string
-     */
-    public function getRequestParam($key, $default = null, $type = DataType::STRING, $is_array = false, $delimiter = '')
-    {
-        return $this->request_params->getRequestParam($key, $default, $type, $is_array, $delimiter);
-    }
-
-
-    /**
-     * check if param exists
-     *
-     * @param string $key
-     * @return bool
-     */
-    public function requestParamIsSet($key)
-    {
-        return $this->request_params->requestParamIsSet($key);
-    }
-
-
-    /**
-     * check if a request parameter exists whose key that matches the supplied wildcard pattern
-     * and return the sanitized value for the first match found
-     * wildcards can be either of the following:
-     *      ? to represent a single character of any type
-     *      * to represent one or more characters of any type
-     *
-     * @param string     $pattern
-     * @param mixed|null $default
-     * @param string     $type      the expected data type for the parameter's value, ie: string, int, bool, etc
-     * @param bool       $is_array  if true, then parameter value will be treated as an array of $type
-     * @param string     $delimiter for CSV type strings that should be returned as an array
-     * @return array|bool|float|int|string
-     */
-    public function getMatch($pattern, $default = null, $type = DataType::STRING, $is_array = false, $delimiter = '')
-    {
-        return $this->request_params->getMatch($pattern, $default, $type, $is_array, $delimiter);
-    }
-
-
-    /**
-     * check if a request parameter exists whose key matches the supplied wildcard pattern
-     * wildcards can be either of the following:
-     *      ? to represent a single character of any type
-     *      * to represent one or more characters of any type
-     * returns true if a match is found or false if not
-     *
-     * @param string $pattern
-     * @return bool
-     */
-    public function matches($pattern)
-    {
-        return $this->request_params->matches($pattern);
-    }
-
-
-    /**
-     * remove param
-     *
-     * @param      $key
-     * @param bool $unset_from_global_too
-     */
-    public function unSetRequestParam($key, $unset_from_global_too = false)
-    {
-        $this->request_params->unSetRequestParam($key, $unset_from_global_too);
-    }
-
-
-    /**
-     * remove params
-     *
-     * @param array $keys
-     * @param bool  $unset_from_global_too
-     */
-    public function unSetRequestParams(array $keys, $unset_from_global_too = false)
-    {
-        $this->request_params->unSetRequestParams($keys, $unset_from_global_too);
-    }
-
-
-    /**
-     * @param string $key
-     * @param bool   $unset_from_global_too
-     * @return void
-     */
-    public function unSetServerParam(string $key, bool $unset_from_global_too = false)
-    {
-        $this->server_params->unSetServerParam($key, $unset_from_global_too);
-    }
-
-
-    /**
-     * @return string
-     */
-    public function ipAddress()
-    {
-        return $this->server_params->ipAddress();
-    }
-
-
-    /**
-     * Gets the request's literal URI. Related to `requestUriAfterSiteHomeUri`, see its description for a comparison.
-     *
-     * @param boolean $relativeToWpRoot    If home_url() is "http://mysite.com/wp/", and a request comes to
-     *                                     "http://mysite.com/wp/wp-json", setting $relativeToWpRoot=true will return
-     *                                     "/wp-json", whereas $relativeToWpRoot=false will return "/wp/wp-json/".
-     * @param boolean $remove_query_params whether or not to return the uri with all query params removed.
-     * @return string
-     */
-    public function requestUri($relativeToWpRoot = false, $remove_query_params = false)
-    {
-        return $this->server_params->requestUri($relativeToWpRoot);
-    }
-
-
-    /**
-     * @return string
-     */
-    public function userAgent()
-    {
-        return $this->server_params->userAgent();
-    }
-
-
-    /**
-     * @param string $user_agent
-     */
-    public function setUserAgent($user_agent = '')
-    {
-        $this->server_params->setUserAgent($user_agent);
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isBot()
-    {
-        return $this->is_bot;
-    }
-
-
-    /**
-     * @param bool $is_bot
-     */
-    public function setIsBot($is_bot)
-    {
-        $this->is_bot = filter_var($is_bot, FILTER_VALIDATE_BOOLEAN);
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isActivation()
-    {
-        return $this->request_type->isActivation();
-    }
-
-
-    /**
-     * @param $is_activation
-     * @return bool
-     */
-    public function setIsActivation($is_activation)
-    {
-        return $this->request_type->setIsActivation($is_activation);
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isAdmin()
-    {
-        return $this->request_type->isAdmin();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isAdminAjax()
-    {
-        return $this->request_type->isAdminAjax();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isAjax()
-    {
-        return $this->request_type->isAjax();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isEeAjax()
-    {
-        return $this->request_type->isEeAjax();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isOtherAjax()
-    {
-        return $this->request_type->isOtherAjax();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isApi()
-    {
-        return $this->request_type->isApi();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isCli()
-    {
-        return $this->request_type->isCli();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isCron()
-    {
-        return $this->request_type->isCron();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isFeed()
-    {
-        return $this->request_type->isFeed();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isFrontend()
-    {
-        return $this->request_type->isFrontend();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isFrontAjax()
-    {
-        return $this->request_type->isFrontAjax();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isGQL()
-    {
-        return $this->request_type->isGQL();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isIframe()
-    {
-        return $this->request_type->isIframe();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isUnitTesting()
-    {
-        return $this->request_type->isUnitTesting();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isWordPressApi()
-    {
-        return $this->request_type->isWordPressApi();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isWordPressHeartbeat()
-    {
-        return $this->request_type->isWordPressHeartbeat();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isWordPressScrape()
-    {
-        return $this->request_type->isWordPressScrape();
-    }
-
-
-    /**
-     * @return string
-     */
-    public function slug()
-    {
-        return $this->request_type->slug();
-    }
-
-
-    /**
-     * returns the path portion of the current request URI with both the WP Root (home_url()) and query params removed
-     *
-     * @return string
-     * @since   $VID:$
-     */
-    public function requestPath()
-    {
-        return $this->requestUri(true, true);
-    }
-
-
-    /**
-     * returns true if the last segment of the current request path (without params) matches the provided string
-     *
-     * @param string $uri_segment
-     * @return bool
-     * @since   $VID:$
-     */
-    public function currentPageIs($uri_segment)
-    {
-        $request_path = $this->requestPath();
-        $current_page = explode('/', $request_path);
-        return end($current_page) === $uri_segment;
-    }
-
-
-    /**
-     * @return RequestTypeContextCheckerInterface
-     */
-    public function getRequestType(): RequestTypeContextCheckerInterface
-    {
-        return $this->request_type;
-    }
+	/**
+	 * $_COOKIE parameters
+	 *
+	 * @var array
+	 */
+	protected $cookies;
+
+	/**
+	 * $_FILES parameters
+	 *
+	 * @var array
+	 */
+	protected $files;
+
+	/**
+	 * true if current user appears to be some kind of bot
+	 *
+	 * @var bool
+	 */
+	protected $is_bot;
+
+	/**
+	 * @var RequestParams
+	 */
+	protected $request_params;
+
+	/**
+	 * @var RequestTypeContextCheckerInterface
+	 */
+	protected $request_type;
+
+	/**
+	 * @var ServerParams
+	 */
+	protected $server_params;
+
+
+	public function __construct(
+		RequestParams $request_params,
+		ServerParams $server_params,
+		array $cookies = [],
+		array $files = []
+	) {
+		$this->cookies        = ! empty($cookies)
+			? $cookies
+			: filter_input_array(INPUT_COOKIE, FILTER_UNSAFE_RAW);
+		$this->files          = ! empty($files) ? $files : $_FILES;
+		$this->request_params = $request_params;
+		$this->server_params  = $server_params;
+	}
+
+
+	/**
+	 * @param RequestTypeContextCheckerInterface $type
+	 */
+	public function setRequestTypeContextChecker(RequestTypeContextCheckerInterface $type)
+	{
+		$this->request_type = $type;
+	}
+
+
+	/**
+	 * @return array
+	 */
+	public function getParams()
+	{
+		return $this->request_params->getParams();
+	}
+
+
+	/**
+	 * @return array
+	 */
+	public function postParams()
+	{
+		return $this->request_params->postParams();
+	}
+
+
+	/**
+	 * @return array
+	 */
+	public function cookieParams()
+	{
+		return $this->cookies;
+	}
+
+
+	/**
+	 * @return array
+	 */
+	public function serverParams()
+	{
+		return $this->server_params->getAllServerParams();
+	}
+
+
+	/**
+	 * @param string     $key
+	 * @param mixed|null $default
+	 * @return array|int|float|string
+	 */
+	public function getServerParam($key, $default = null)
+	{
+		return $this->server_params->getServerParam($key, $default);
+	}
+
+
+	/**
+	 * @param string                 $key
+	 * @param array|int|float|string $value
+	 * @param bool                   $set_global_too
+	 * @return void
+	 */
+	public function setServerParam(string $key, $value, bool $set_global_too = false)
+	{
+		$this->server_params->setServerParam($key, $value, $set_global_too);
+	}
+
+
+	/**
+	 * @param string $key
+	 * @return bool
+	 */
+	public function serverParamIsSet($key)
+	{
+		return $this->server_params->serverParamIsSet($key);
+	}
+
+
+	/**
+	 * @return array
+	 */
+	public function filesParams()
+	{
+		return $this->files;
+	}
+
+
+	/**
+	 * returns sanitized contents of $_REQUEST
+	 *
+	 * @return array
+	 */
+	public function requestParams()
+	{
+		return $this->request_params->requestParams();
+	}
+
+
+	/**
+	 * @param string     $key
+	 * @param mixed|null $value
+	 * @param bool       $override_ee
+	 * @return void
+	 */
+	public function setRequestParam($key, $value, $override_ee = false)
+	{
+		$this->request_params->setRequestParam($key, $value, $override_ee);
+	}
+
+
+	/**
+	 * merges the incoming array of parameters into the existing request parameters
+	 *
+	 * @param array $request_params
+	 * @return void
+	 * @since   4.10.24.p
+	 */
+	public function mergeRequestParams(array $request_params)
+	{
+		$this->request_params->mergeRequestParams($request_params);
+	}
+
+
+	/**
+	 * returns sanitized value for a request param if the given key exists
+	 *
+	 * @param string     $key
+	 * @param mixed|null $default
+	 * @param string     $type      the expected data type for the parameter's value, ie: string, int, bool, etc
+	 * @param bool       $is_array  if true, then parameter value will be treated as an array of $type
+	 * @param string     $delimiter for CSV type strings that should be returned as an array
+	 * @return array|bool|float|int|string
+	 */
+	public function getRequestParam($key, $default = null, $type = DataType::STRING, $is_array = false, $delimiter = '')
+	{
+		return $this->request_params->getRequestParam($key, $default, $type, $is_array, $delimiter);
+	}
+
+
+	/**
+	 * check if param exists
+	 *
+	 * @param string $key
+	 * @return bool
+	 */
+	public function requestParamIsSet($key)
+	{
+		return $this->request_params->requestParamIsSet($key);
+	}
+
+
+	/**
+	 * check if a request parameter exists whose key that matches the supplied wildcard pattern
+	 * and return the sanitized value for the first match found
+	 * wildcards can be either of the following:
+	 *      ? to represent a single character of any type
+	 *      * to represent one or more characters of any type
+	 *
+	 * @param string     $pattern
+	 * @param mixed|null $default
+	 * @param string     $type      the expected data type for the parameter's value, ie: string, int, bool, etc
+	 * @param bool       $is_array  if true, then parameter value will be treated as an array of $type
+	 * @param string     $delimiter for CSV type strings that should be returned as an array
+	 * @return array|bool|float|int|string
+	 */
+	public function getMatch($pattern, $default = null, $type = DataType::STRING, $is_array = false, $delimiter = '')
+	{
+		return $this->request_params->getMatch($pattern, $default, $type, $is_array, $delimiter);
+	}
+
+
+	/**
+	 * check if a request parameter exists whose key matches the supplied wildcard pattern
+	 * wildcards can be either of the following:
+	 *      ? to represent a single character of any type
+	 *      * to represent one or more characters of any type
+	 * returns true if a match is found or false if not
+	 *
+	 * @param string $pattern
+	 * @return bool
+	 */
+	public function matches($pattern)
+	{
+		return $this->request_params->matches($pattern);
+	}
+
+
+	/**
+	 * remove param
+	 *
+	 * @param      $key
+	 * @param bool $unset_from_global_too
+	 */
+	public function unSetRequestParam($key, $unset_from_global_too = false)
+	{
+		$this->request_params->unSetRequestParam($key, $unset_from_global_too);
+	}
+
+
+	/**
+	 * remove params
+	 *
+	 * @param array $keys
+	 * @param bool  $unset_from_global_too
+	 */
+	public function unSetRequestParams(array $keys, $unset_from_global_too = false)
+	{
+		$this->request_params->unSetRequestParams($keys, $unset_from_global_too);
+	}
+
+
+	/**
+	 * @param string $key
+	 * @param bool   $unset_from_global_too
+	 * @return void
+	 */
+	public function unSetServerParam(string $key, bool $unset_from_global_too = false)
+	{
+		$this->server_params->unSetServerParam($key, $unset_from_global_too);
+	}
+
+
+	/**
+	 * @return string
+	 */
+	public function ipAddress()
+	{
+		return $this->server_params->ipAddress();
+	}
+
+
+	/**
+	 * Gets the request's literal URI. Related to `requestUriAfterSiteHomeUri`, see its description for a comparison.
+	 *
+	 * @param boolean $relativeToWpRoot    If home_url() is "http://mysite.com/wp/", and a request comes to
+	 *                                     "http://mysite.com/wp/wp-json", setting $relativeToWpRoot=true will return
+	 *                                     "/wp-json", whereas $relativeToWpRoot=false will return "/wp/wp-json/".
+	 * @param boolean $remove_query_params whether or not to return the uri with all query params removed.
+	 * @return string
+	 */
+	public function requestUri($relativeToWpRoot = false, $remove_query_params = false)
+	{
+		return $this->server_params->requestUri($relativeToWpRoot);
+	}
+
+
+	/**
+	 * @return string
+	 */
+	public function userAgent()
+	{
+		return $this->server_params->userAgent();
+	}
+
+
+	/**
+	 * @param string $user_agent
+	 */
+	public function setUserAgent($user_agent = '')
+	{
+		$this->server_params->setUserAgent($user_agent);
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isBot()
+	{
+		return $this->is_bot;
+	}
+
+
+	/**
+	 * @param bool $is_bot
+	 */
+	public function setIsBot($is_bot)
+	{
+		$this->is_bot = filter_var($is_bot, FILTER_VALIDATE_BOOLEAN);
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isActivation()
+	{
+		return $this->request_type->isActivation();
+	}
+
+
+	/**
+	 * @param $is_activation
+	 * @return bool
+	 */
+	public function setIsActivation($is_activation)
+	{
+		return $this->request_type->setIsActivation($is_activation);
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isAdmin()
+	{
+		return $this->request_type->isAdmin();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isAdminAjax()
+	{
+		return $this->request_type->isAdminAjax();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isAjax()
+	{
+		return $this->request_type->isAjax();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isEeAjax()
+	{
+		return $this->request_type->isEeAjax();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isOtherAjax()
+	{
+		return $this->request_type->isOtherAjax();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isApi()
+	{
+		return $this->request_type->isApi();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isCli()
+	{
+		return $this->request_type->isCli();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isCron()
+	{
+		return $this->request_type->isCron();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isFeed()
+	{
+		return $this->request_type->isFeed();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isFrontend()
+	{
+		return $this->request_type->isFrontend();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isFrontAjax()
+	{
+		return $this->request_type->isFrontAjax();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isGQL()
+	{
+		return $this->request_type->isGQL();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isIframe()
+	{
+		return $this->request_type->isIframe();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isUnitTesting()
+	{
+		return $this->request_type->isUnitTesting();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isWordPressApi()
+	{
+		return $this->request_type->isWordPressApi();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isWordPressHeartbeat()
+	{
+		return $this->request_type->isWordPressHeartbeat();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isWordPressScrape()
+	{
+		return $this->request_type->isWordPressScrape();
+	}
+
+
+	/**
+	 * @return string
+	 */
+	public function slug()
+	{
+		return $this->request_type->slug();
+	}
+
+
+	/**
+	 * returns the path portion of the current request URI with both the WP Root (home_url()) and query params removed
+	 *
+	 * @return string
+	 * @since   $VID:$
+	 */
+	public function requestPath()
+	{
+		return $this->requestUri(true, true);
+	}
+
+
+	/**
+	 * returns true if the last segment of the current request path (without params) matches the provided string
+	 *
+	 * @param string $uri_segment
+	 * @return bool
+	 * @since   $VID:$
+	 */
+	public function currentPageIs($uri_segment)
+	{
+		$request_path = $this->requestPath();
+		$current_page = explode('/', $request_path);
+		return end($current_page) === $uri_segment;
+	}
+
+
+	/**
+	 * @return RequestTypeContextCheckerInterface
+	 */
+	public function getRequestType(): RequestTypeContextCheckerInterface
+	{
+		return $this->request_type;
+	}
 }

core/services/assets/I18nRegistry.php

Indentation +38 added lines, -38 removed lines

@@ -13,46 +13,46 @@
  */
 class I18nRegistry
 {
-    /**
-     * @var DomainInterface
-     */
-    private $domain;
+	/**
+	 * @var DomainInterface
+	 */
+	private $domain;
 
-    /**
-     * @var JedLocaleData $jed_locale
-     */
-    private $jed_locale;
+	/**
+	 * @var JedLocaleData $jed_locale
+	 */
+	private $jed_locale;
 
-    /**
-     * I18nRegistry constructor.
-     *
-     * @param DomainInterface $domain
-     * @param JedLocaleData $jed_locale
-     * @param array() $i18n_map
-     * @deprecated $VID:$
-     */
-    public function __construct(DomainInterface $domain, JedLocaleData $jed_locale, array $i18n_map = [])
-    {
-        $this->domain = $domain;
-        $this->jed_locale = $jed_locale;
-    }
+	/**
+	 * I18nRegistry constructor.
+	 *
+	 * @param DomainInterface $domain
+	 * @param JedLocaleData $jed_locale
+	 * @param array() $i18n_map
+	 * @deprecated $VID:$
+	 */
+	public function __construct(DomainInterface $domain, JedLocaleData $jed_locale, array $i18n_map = [])
+	{
+		$this->domain = $domain;
+		$this->jed_locale = $jed_locale;
+	}
 
-    /**
-     * @param string $handle The script handle reference.
-     * @param string $domain The i18n domain for the strings.
-     * @deprecated $VID:$
-     */
-    public function registerScriptI18n(string $handle, string $domain = Domain::TEXT_DOMAIN)
-    {
-    }
+	/**
+	 * @param string $handle The script handle reference.
+	 * @param string $domain The i18n domain for the strings.
+	 * @deprecated $VID:$
+	 */
+	public function registerScriptI18n(string $handle, string $domain = Domain::TEXT_DOMAIN)
+	{
+	}
 
-    /**
-     * @param array $handles Array of registered script handles.
-     * @return array
-     * @deprecated $VID:$
-     */
-    public function queueI18n(array $handles): array
-    {
-        return $handles;
-    }
+	/**
+	 * @param array $handles Array of registered script handles.
+	 * @return array
+	 * @deprecated $VID:$
+	 */
+	public function queueI18n(array $handles): array
+	{
+		return $handles;
+	}
 }

core/db_models/EEM_Base.model.php

Indentation +6593 added lines, -6593 removed lines

@@ -37,6599 +37,6599 @@
  */
 abstract class EEM_Base extends EE_Base implements ResettableInterface
 {
-    /**
-     * Flag to indicate whether the values provided to EEM_Base have already been prepared
-     * by the model object or not (ie, the model object has used the field's _prepare_for_set function on the values).
-     * They almost always WILL NOT, but it's not necessarily a requirement.
-     * For example, if you want to run EEM_Event::instance()->get_all(array(array('EVT_ID'=>$_GET['event_id'])));
-     *
-     * @var boolean
-     */
-    private $_values_already_prepared_by_model_object = 0;
-
-    /**
-     * when $_values_already_prepared_by_model_object equals this, we assume
-     * the data is just like form input that needs to have the model fields'
-     * prepare_for_set and prepare_for_use_in_db called on it
-     */
-    const not_prepared_by_model_object = 0;
-
-    /**
-     * when $_values_already_prepared_by_model_object equals this, we
-     * assume this value is coming from a model object and doesn't need to have
-     * prepare_for_set called on it, just prepare_for_use_in_db is used
-     */
-    const prepared_by_model_object = 1;
-
-    /**
-     * when $_values_already_prepared_by_model_object equals this, we assume
-     * the values are already to be used in the database (ie no processing is done
-     * on them by the model's fields)
-     */
-    const prepared_for_use_in_db = 2;
-
-
-    protected $singular_item = 'Item';
-
-    protected $plural_item   = 'Items';
-
-    /**
-     * @type EE_Table_Base[] $_tables array of EE_Table objects for defining which tables comprise this model.
-     */
-    protected $_tables;
-
-    /**
-     * with two levels: top-level has array keys which are database table aliases (ie, keys in _tables)
-     * and the value is an array. Each of those sub-arrays have keys of field names (eg 'ATT_ID', which should also be
-     * variable names on the model objects (eg, EE_Attendee), and the keys should be children of EE_Model_Field
-     *
-     * @var EE_Model_Field_Base[][] $_fields
-     */
-    protected $_fields;
-
-    /**
-     * array of different kinds of relations
-     *
-     * @var EE_Model_Relation_Base[] $_model_relations
-     */
-    protected $_model_relations = [];
-
-    /**
-     * @var EE_Index[] $_indexes
-     */
-    protected $_indexes = [];
-
-    /**
-     * Default strategy for getting where conditions on this model. This strategy is used to get default
-     * where conditions which are added to get_all, update, and delete queries. They can be overridden
-     * by setting the same columns as used in these queries in the query yourself.
-     *
-     * @var EE_Default_Where_Conditions
-     */
-    protected $_default_where_conditions_strategy;
-
-    /**
-     * Strategy for getting conditions on this model when 'default_where_conditions' equals 'minimum'.
-     * This is particularly useful when you want something between 'none' and 'default'
-     *
-     * @var EE_Default_Where_Conditions
-     */
-    protected $_minimum_where_conditions_strategy;
-
-    /**
-     * String describing how to find the "owner" of this model's objects.
-     * When there is a foreign key on this model to the wp_users table, this isn't needed.
-     * But when there isn't, this indicates which related model, or transiently-related model,
-     * has the foreign key to the wp_users table.
-     * Eg, for EEM_Registration this would be 'Event' because registrations are directly
-     * related to events, and events have a foreign key to wp_users.
-     * On EEM_Transaction, this would be 'Transaction.Event'
-     *
-     * @var string
-     */
-    protected $_model_chain_to_wp_user = '';
-
-    /**
-     * String describing how to find the model with a password controlling access to this model. This property has the
-     * same format as $_model_chain_to_wp_user. This is primarily used by the query param "exclude_protected".
-     * This value is the path of models to follow to arrive at the model with the password field.
-     * If it is an empty string, it means this model has the password field. If it is null, it means there is no
-     * model with a password that should affect reading this on the front-end.
-     * Eg this is an empty string for the Event model because it has a password.
-     * This is null for the Registration model, because its event's password has no bearing on whether
-     * you can read the registration or not on the front-end (it just depends on your capabilities.)
-     * This is 'Datetime.Event' on the Ticket model, because model queries for tickets that set "exclude_protected"
-     * should hide tickets for datetimes for events that have a password set.
-     *
-     * @var string |null
-     */
-    protected $model_chain_to_password = null;
-
-    /**
-     * This is a flag typically set by updates so that we don't load the where strategy on updates because updates
-     * don't need it (particularly CPT models)
-     *
-     * @var bool
-     */
-    protected $_ignore_where_strategy = false;
-
-    /**
-     * String used in caps relating to this model. Eg, if the caps relating to this
-     * model are 'ee_edit_events', 'ee_read_events', etc, it would be 'events'.
-     *
-     * @var string. If null it hasn't been initialized yet. If false then we
-     * have indicated capabilities don't apply to this
-     */
-    protected $_caps_slug = null;
-
-    /**
-     * 2d array where top-level keys are one of EEM_Base::valid_cap_contexts(),
-     * and next-level keys are capability names, and each's value is a
-     * EE_Default_Where_Condition. If the requester requests to apply caps to the query,
-     * they specify which context to use (ie, frontend, backend, edit or delete)
-     * and then each capability in the corresponding sub-array that they're missing
-     * adds the where conditions onto the query.
-     *
-     * @var array
-     */
-    protected $_cap_restrictions = [
-        self::caps_read       => [],
-        self::caps_read_admin => [],
-        self::caps_edit       => [],
-        self::caps_delete     => [],
-    ];
-
-    /**
-     * Array defining which cap restriction generators to use to create default
-     * cap restrictions to put in EEM_Base::_cap_restrictions.
-     * Array-keys are one of EEM_Base::valid_cap_contexts(), and values are a child of
-     * EE_Restriction_Generator_Base. If you don't want any cap restrictions generated
-     * automatically set this to false (not just null).
-     *
-     * @var EE_Restriction_Generator_Base[]
-     */
-    protected $_cap_restriction_generators = [];
-
-    /**
-     * constants used to categorize capability restrictions on EEM_Base::_caps_restrictions
-     */
-    const caps_read       = 'read';
-
-    const caps_read_admin = 'read_admin';
-
-    const caps_edit       = 'edit';
-
-    const caps_delete     = 'delete';
-
-    /**
-     * Keys are all the cap contexts (ie constants EEM_Base::_caps_*) and values are their 'action'
-     * as how they'd be used in capability names. Eg EEM_Base::caps_read ('read_frontend')
-     * maps to 'read' because when looking for relevant permissions we're going to use
-     * 'read' in teh capabilities names like 'ee_read_events' etc.
-     *
-     * @var array
-     */
-    protected $_cap_contexts_to_cap_action_map = [
-        self::caps_read       => 'read',
-        self::caps_read_admin => 'read',
-        self::caps_edit       => 'edit',
-        self::caps_delete     => 'delete',
-    ];
-
-    /**
-     * Timezone
-     * This gets set via the constructor so that we know what timezone incoming strings|timestamps are in when there
-     * are EE_Datetime_Fields in use.  This can also be used before a get to set what timezone you want strings coming
-     * out of the created objects.  NOT all EEM_Base child classes use this property but any that use a
-     * EE_Datetime_Field data type will have access to it.
-     *
-     * @var string
-     */
-    protected $_timezone;
-
-
-    /**
-     * This holds the id of the blog currently making the query.  Has no bearing on single site but is used for
-     * multisite.
-     *
-     * @var int
-     */
-    protected static $_model_query_blog_id;
-
-    /**
-     * A copy of _fields, except the array keys are the model names pointed to by
-     * the field
-     *
-     * @var EE_Model_Field_Base[]
-     */
-    private $_cache_foreign_key_to_fields = [];
-
-    /**
-     * Cached list of all the fields on the model, indexed by their name
-     *
-     * @var EE_Model_Field_Base[]
-     */
-    private $_cached_fields = null;
-
-    /**
-     * Cached list of all the fields on the model, except those that are
-     * marked as only pertinent to the database
-     *
-     * @var EE_Model_Field_Base[]
-     */
-    private $_cached_fields_non_db_only = null;
-
-    /**
-     * A cached reference to the primary key for quick lookup
-     *
-     * @var EE_Model_Field_Base
-     */
-    private $_primary_key_field = null;
-
-    /**
-     * Flag indicating whether this model has a primary key or not
-     *
-     * @var boolean
-     */
-    protected $_has_primary_key_field = null;
-
-    /**
-     * array in the format:  [ FK alias => full PK ]
-     * where keys are local column name aliases for foreign keys
-     * and values are the fully qualified column name for the primary key they represent
-     *  ex:
-     *      [ 'Event.EVT_wp_user' => 'WP_User.ID' ]
-     *
-     * @var array $foreign_key_aliases
-     */
-    protected $foreign_key_aliases = [];
-
-    /**
-     * Whether or not this model is based off a table in WP core only (CPTs should set
-     * this to FALSE, but if we were to make an EE_WP_Post model, it should set this to true).
-     * This should be true for models that deal with data that should exist independent of EE.
-     * For example, if the model can read and insert data that isn't used by EE, this should be true.
-     * It would be false, however, if you could guarantee the model would only interact with EE data,
-     * even if it uses a WP core table (eg event and venue models set this to false for that reason:
-     * they can only read and insert events and venues custom post types, not arbitrary post types)
-     *
-     * @var boolean
-     */
-    protected $_wp_core_model = false;
-
-    /**
-     * @var bool stores whether this model has a password field or not.
-     * null until initialized by hasPasswordField()
-     */
-    protected $has_password_field;
-
-    /**
-     * @var EE_Password_Field|null Automatically set when calling getPasswordField()
-     */
-    protected $password_field;
-
-    /**
-     *    List of valid operators that can be used for querying.
-     * The keys are all operators we'll accept, the values are the real SQL
-     * operators used
-     *
-     * @var array
-     */
-    protected $_valid_operators = [
-        '='           => '=',
-        '<='          => '<=',
-        '<'           => '<',
-        '>='          => '>=',
-        '>'           => '>',
-        '!='          => '!=',
-        'LIKE'        => 'LIKE',
-        'like'        => 'LIKE',
-        'NOT_LIKE'    => 'NOT LIKE',
-        'not_like'    => 'NOT LIKE',
-        'NOT LIKE'    => 'NOT LIKE',
-        'not like'    => 'NOT LIKE',
-        'IN'          => 'IN',
-        'in'          => 'IN',
-        'NOT_IN'      => 'NOT IN',
-        'not_in'      => 'NOT IN',
-        'NOT IN'      => 'NOT IN',
-        'not in'      => 'NOT IN',
-        'between'     => 'BETWEEN',
-        'BETWEEN'     => 'BETWEEN',
-        'IS_NOT_NULL' => 'IS NOT NULL',
-        'is_not_null' => 'IS NOT NULL',
-        'IS NOT NULL' => 'IS NOT NULL',
-        'is not null' => 'IS NOT NULL',
-        'IS_NULL'     => 'IS NULL',
-        'is_null'     => 'IS NULL',
-        'IS NULL'     => 'IS NULL',
-        'is null'     => 'IS NULL',
-        'REGEXP'      => 'REGEXP',
-        'regexp'      => 'REGEXP',
-        'NOT_REGEXP'  => 'NOT REGEXP',
-        'not_regexp'  => 'NOT REGEXP',
-        'NOT REGEXP'  => 'NOT REGEXP',
-        'not regexp'  => 'NOT REGEXP',
-    ];
-
-    /**
-     * operators that work like 'IN', accepting a comma-separated list of values inside brackets. Eg '(1,2,3)'
-     *
-     * @var array
-     */
-    protected $_in_style_operators = ['IN', 'NOT IN'];
-
-    /**
-     * operators that work like 'BETWEEN'.  Typically used for datetime calculations, i.e. "BETWEEN '12-1-2011' AND
-     * '12-31-2012'"
-     *
-     * @var array
-     */
-    protected $_between_style_operators = ['BETWEEN'];
-
-    /**
-     * Operators that work like SQL's like: input should be assumed to be a string, already prepared for a LIKE query.
-     *
-     * @var array
-     */
-    protected $_like_style_operators = ['LIKE', 'NOT LIKE'];
-
-    /**
-     * operators that are used for handling NUll and !NULL queries.  Typically used for when checking if a row exists
-     * on a join table.
-     *
-     * @var array
-     */
-    protected $_null_style_operators = ['IS NOT NULL', 'IS NULL'];
-
-    /**
-     * Allowed values for $query_params['order'] for ordering in queries
-     *
-     * @var array
-     */
-    protected $_allowed_order_values = ['asc', 'desc', 'ASC', 'DESC'];
-
-    /**
-     * When these are keys in a WHERE or HAVING clause, they are handled much differently
-     * than regular field names. It is assumed that their values are an array of WHERE conditions
-     *
-     * @var array
-     */
-    private $_logic_query_param_keys = ['not', 'and', 'or', 'NOT', 'AND', 'OR'];
-
-    /**
-     * Allowed keys in $query_params arrays passed into queries. Note that 0 is meant to always be a
-     * 'where', but 'where' clauses are so common that we thought we'd omit it
-     *
-     * @var array
-     */
-    private $_allowed_query_params = [
-        0,
-        'limit',
-        'order_by',
-        'group_by',
-        'having',
-        'force_join',
-        'order',
-        'on_join_limit',
-        'default_where_conditions',
-        'caps',
-        'extra_selects',
-        'exclude_protected',
-    ];
-
-    /**
-     * All the data types that can be used in $wpdb->prepare statements.
-     *
-     * @var array
-     */
-    private $_valid_wpdb_data_types = ['%d', '%s', '%f'];
-
-    /**
-     * @var EE_Registry $EE
-     */
-    protected $EE = null;
-
-
-    /**
-     * Property which, when set, will have this model echo out the next X queries to the page for debugging.
-     *
-     * @var int
-     */
-    protected $_show_next_x_db_queries = 0;
-
-    /**
-     * When using _get_all_wpdb_results, you can specify a custom selection. If you do so,
-     * it gets saved on this property as an instance of CustomSelects so those selections can be used in
-     * WHERE, GROUP_BY, etc.
-     *
-     * @var CustomSelects
-     */
-    protected $_custom_selections = [];
-
-    /**
-     * key => value Entity Map using  array( EEM_Base::$_model_query_blog_id => array( ID => model object ) )
-     * caches every model object we've fetched from the DB on this request
-     *
-     * @var array
-     */
-    protected $_entity_map;
-
-    /**
-     * @var LoaderInterface
-     */
-    protected static $loader;
-
-    /**
-     * @var Mirror
-     */
-    private static $mirror;
-
-
-    /**
-     * constant used to show EEM_Base has not yet verified the db on this http request
-     */
-    const db_verified_none = 0;
-
-    /**
-     * constant used to show EEM_Base has verified the EE core db on this http request,
-     * but not the addons' dbs
-     */
-    const db_verified_core = 1;
-
-    /**
-     * constant used to show EEM_Base has verified the addons' dbs (and implicitly
-     * the EE core db too)
-     */
-    const db_verified_addons = 2;
-
-    /**
-     * indicates whether an EEM_Base child has already re-verified the DB
-     * is ok (we don't want to do it repetitively). Should be set to one the constants
-     * looking like EEM_Base::db_verified_*
-     *
-     * @var int - 0 = none, 1 = core, 2 = addons
-     */
-    protected static $_db_verification_level = EEM_Base::db_verified_none;
-
-    /**
-     * @const constant for 'default_where_conditions' to apply default where conditions to ALL queried models
-     *        (eg, if retrieving registrations ordered by their datetimes, this will only return non-trashed
-     *        registrations for non-trashed tickets for non-trashed datetimes)
-     */
-    const default_where_conditions_all = 'all';
-
-    /**
-     * @const constant for 'default_where_conditions' to apply default where conditions to THIS model only, but
-     *        no other models which are joined to (eg, if retrieving registrations ordered by their datetimes, this will
-     *        return non-trashed registrations, regardless of the related datetimes and tickets' statuses).
-     *        It is preferred to use EEM_Base::default_where_conditions_minimum_others because, when joining to
-     *        models which share tables with other models, this can return data for the wrong model.
-     */
-    const default_where_conditions_this_only = 'this_model_only';
-
-    /**
-     * @const constant for 'default_where_conditions' to apply default where conditions to other models queried,
-     *        but not the current model (eg, if retrieving registrations ordered by their datetimes, this will
-     *        return all registrations related to non-trashed tickets and non-trashed datetimes)
-     */
-    const default_where_conditions_others_only = 'other_models_only';
-
-    /**
-     * @const constant for 'default_where_conditions' to apply minimum where conditions to all models queried.
-     *        For most models this the same as EEM_Base::default_where_conditions_none, except for models which share
-     *        their table with other models, like the Event and Venue models. For example, when querying for events
-     *        ordered by their venues' name, this will be sure to only return real events with associated real venues
-     *        (regardless of whether those events and venues are trashed)
-     *        In contrast, using EEM_Base::default_where_conditions_none would could return WP posts other than EE
-     *        events.
-     */
-    const default_where_conditions_minimum_all = 'minimum';
-
-    /**
-     * @const constant for 'default_where_conditions' to apply apply where conditions to other models, and full default
-     *        where conditions for the queried model (eg, when querying events ordered by venues' names, this will
-     *        return non-trashed events for any venues, regardless of whether those associated venues are trashed or
-     *        not)
-     */
-    const default_where_conditions_minimum_others = 'full_this_minimum_others';
-
-    /**
-     * @const constant for 'default_where_conditions' to NOT apply any where conditions. This should very rarely be
-     *        used, because when querying from a model which shares its table with another model (eg Events and Venues)
-     *        it's possible it will return table entries for other models. You should use
-     *        EEM_Base::default_where_conditions_minimum_all instead.
-     */
-    const default_where_conditions_none = 'none';
-
-
-    /**
-     * About all child constructors:
-     * they should define the _tables, _fields and _model_relations arrays.
-     * Should ALWAYS be called after child constructor.
-     * In order to make the child constructors to be as simple as possible, this parent constructor
-     * finalizes constructing all the object's attributes.
-     * Generally, rather than requiring a child to code
-     * $this->_tables = array(
-     *        'Event_Post_Table' => new EE_Table('Event_Post_Table','wp_posts')
-     *        ...);
-     *  (thus repeating itself in the array key and in the constructor of the new EE_Table,)
-     * each EE_Table has a function to set the table's alias after the constructor, using
-     * the array key ('Event_Post_Table'), instead of repeating it. The model fields and model relations
-     * do something similar.
-     *
-     * @param null $timezone
-     * @throws EE_Error
-     */
-    protected function __construct($timezone = null)
-    {
-        // check that the model has not been loaded too soon
-        if (! did_action('AHEE__EE_System__load_espresso_addons')) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'The %1$s model can not be loaded before the "AHEE__EE_System__load_espresso_addons" hook has been called. This gives other addons a chance to extend this model.',
-                        'event_espresso'
-                    ),
-                    get_class($this)
-                )
-            );
-        }
-        /**
-         * Set blogid for models to current blog. However we ONLY do this if $_model_query_blog_id is not already set.
-         */
-        if (empty(EEM_Base::$_model_query_blog_id)) {
-            EEM_Base::set_model_query_blog_id();
-        }
-        /**
-         * Filters the list of tables on a model. It is best to NOT use this directly and instead
-         * just use EE_Register_Model_Extension
-         *
-         * @var EE_Table_Base[] $_tables
-         */
-        $this->_tables = (array) apply_filters('FHEE__' . get_class($this) . '__construct__tables', $this->_tables);
-        foreach ($this->_tables as $table_alias => $table_obj) {
-            /** @var $table_obj EE_Table_Base */
-            $table_obj->_construct_finalize_with_alias($table_alias);
-            if ($table_obj instanceof EE_Secondary_Table) {
-                $table_obj->_construct_finalize_set_table_to_join_with($this->_get_main_table());
-            }
-        }
-        /**
-         * Filters the list of fields on a model. It is best to NOT use this directly and instead just use
-         * EE_Register_Model_Extension
-         *
-         * @param EE_Model_Field_Base[] $_fields
-         */
-        $this->_fields = (array) apply_filters('FHEE__' . get_class($this) . '__construct__fields', $this->_fields);
-        $this->_invalidate_field_caches();
-        foreach ($this->_fields as $table_alias => $fields_for_table) {
-            if (! array_key_exists($table_alias, $this->_tables)) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            "Table alias %s does not exist in EEM_Base child's _tables array. Only tables defined are %s",
-                            'event_espresso'
-                        ),
-                        $table_alias,
-                        implode(",", $this->_fields)
-                    )
-                );
-            }
-            foreach ($fields_for_table as $field_name => $field_obj) {
-                /** @var $field_obj EE_Model_Field_Base | EE_Primary_Key_Field_Base */
-                // primary key field base has a slightly different _construct_finalize
-                /** @var $field_obj EE_Model_Field_Base */
-                $field_obj->_construct_finalize($table_alias, $field_name, $this->get_this_model_name());
-            }
-        }
-        // everything is related to Extra_Meta
-        if (get_class($this) !== 'EEM_Extra_Meta') {
-            // make extra meta related to everything, but don't block deleting things just
-            // because they have related extra meta info. For now just orphan those extra meta
-            // in the future we should automatically delete them
-            $this->_model_relations['Extra_Meta'] = new EE_Has_Many_Any_Relation(false);
-        }
-        // and change logs
-        if (get_class($this) !== 'EEM_Change_Log') {
-            $this->_model_relations['Change_Log'] = new EE_Has_Many_Any_Relation(false);
-        }
-        /**
-         * Filters the list of relations on a model. It is best to NOT use this directly and instead just use
-         * EE_Register_Model_Extension
-         *
-         * @param EE_Model_Relation_Base[] $_model_relations
-         */
-        $this->_model_relations = (array) apply_filters(
-            'FHEE__' . get_class($this) . '__construct__model_relations',
-            $this->_model_relations
-        );
-        foreach ($this->_model_relations as $model_name => $relation_obj) {
-            /** @var $relation_obj EE_Model_Relation_Base */
-            $relation_obj->_construct_finalize_set_models($this->get_this_model_name(), $model_name);
-        }
-        foreach ($this->_indexes as $index_name => $index_obj) {
-            $index_obj->_construct_finalize($index_name, $this->get_this_model_name());
-        }
-        $this->set_timezone($timezone);
-        // finalize default where condition strategy, or set default
-        if (! $this->_default_where_conditions_strategy) {
-            // nothing was set during child constructor, so set default
-            $this->_default_where_conditions_strategy = new EE_Default_Where_Conditions();
-        }
-        $this->_default_where_conditions_strategy->_finalize_construct($this);
-        if (! $this->_minimum_where_conditions_strategy) {
-            // nothing was set during child constructor, so set default
-            $this->_minimum_where_conditions_strategy = new EE_Default_Where_Conditions();
-        }
-        $this->_minimum_where_conditions_strategy->_finalize_construct($this);
-        // if the cap slug hasn't been set, and we haven't set it to false on purpose
-        // to indicate to NOT set it, set it to the logical default
-        if ($this->_caps_slug === null) {
-            $this->_caps_slug = EEH_Inflector::pluralize_and_lower($this->get_this_model_name());
-        }
-        // initialize the standard cap restriction generators if none were specified by the child constructor
-        if (is_array($this->_cap_restriction_generators)) {
-            foreach ($this->cap_contexts_to_cap_action_map() as $cap_context => $action) {
-                if (! isset($this->_cap_restriction_generators[ $cap_context ])) {
-                    $this->_cap_restriction_generators[ $cap_context ] = apply_filters(
-                        'FHEE__EEM_Base___construct__standard_cap_restriction_generator',
-                        new EE_Restriction_Generator_Protected(),
-                        $cap_context,
-                        $this
-                    );
-                }
-            }
-        }
-        // if there are cap restriction generators, use them to make the default cap restrictions
-        if (is_array($this->_cap_restriction_generators)) {
-            foreach ($this->_cap_restriction_generators as $context => $generator_object) {
-                if (! $generator_object) {
-                    continue;
-                }
-                if (! $generator_object instanceof EE_Restriction_Generator_Base) {
-                    throw new EE_Error(
-                        sprintf(
-                            esc_html__(
-                                'Index "%1$s" in the model %2$s\'s _cap_restriction_generators is not a child of EE_Restriction_Generator_Base. It should be that or NULL.',
-                                'event_espresso'
-                            ),
-                            $context,
-                            $this->get_this_model_name()
-                        )
-                    );
-                }
-                $action = $this->cap_action_for_context($context);
-                if (! $generator_object->construction_finalized()) {
-                    $generator_object->_construct_finalize($this, $action);
-                }
-            }
-        }
-        do_action('AHEE__' . get_class($this) . '__construct__end');
-    }
-
-
-    /**
-     * @return LoaderInterface
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected static function getLoader(): LoaderInterface
-    {
-        if (! EEM_Base::$loader instanceof LoaderInterface) {
-            EEM_Base::$loader = LoaderFactory::getLoader();
-        }
-        return EEM_Base::$loader;
-    }
-
-
-    /**
-     * @return Mirror
-     * @since   $VID:$
-     */
-    private static function getMirror(): Mirror
-    {
-        if (! EEM_Base::$mirror instanceof Mirror) {
-            EEM_Base::$mirror = EEM_Base::getLoader()->getShared(Mirror::class);
-        }
-        return EEM_Base::$mirror;
-    }
-
-
-    /**
-     * @param string $model_class_Name
-     * @param string $timezone
-     * @return array
-     * @throws ReflectionException
-     * @since   $VID:$
-     */
-    private static function getModelArguments(string $model_class_Name, string $timezone): array
-    {
-        $arguments = [$timezone];
-        $params    = EEM_Base::getMirror()->getParameters($model_class_Name);
-        if (count($params) > 1) {
-            if ($params[1]->getName() === 'model_field_factory') {
-                $arguments = [
-                    $timezone,
-                    EEM_Base::getLoader()->getShared(ModelFieldFactory::class),
-                ];
-            } elseif ($model_class_Name === 'EEM_Form_Section') {
-                $arguments = [
-                    EEM_Base::getLoader()->getShared('EventEspresso\core\services\form\meta\FormStatus'),
-                    $timezone,
-                ];
-            } elseif ($model_class_Name === 'EEM_Form_Element') {
-                $arguments = [
-                    EEM_Base::getLoader()->getShared('EventEspresso\core\services\form\meta\FormStatus'),
-                    EEM_Base::getLoader()->getShared('EventEspresso\core\services\form\meta\InputTypes'),
-                    $timezone,
-                ];
-            }
-        }
-        return $arguments;
-    }
-
-
-    /**
-     * This function is a singleton method used to instantiate the Espresso_model object
-     *
-     * @param string|null $timezone   string representing the timezone we want to set for returned Date Time Strings
-     *                                (and any incoming timezone data that gets saved).
-     *                                Note this just sends the timezone info to the date time model field objects.
-     *                                Default is NULL
-     *                                (and will be assumed using the set timezone in the 'timezone_string' wp option)
-     * @return static (as in the concrete child class)
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function instance($timezone = null)
-    {
-        // check if instance of Espresso_model already exists
-        if (! static::$_instance instanceof static) {
-            $arguments = EEM_Base::getModelArguments(static::class, (string) $timezone);
-            $model     = new static(...$arguments);
-            EEM_Base::getLoader()->share(static::class, $model, $arguments);
-            static::$_instance = $model;
-        }
-        // we might have a timezone set, let set_timezone decide what to do with it
-        if ($timezone) {
-            static::$_instance->set_timezone($timezone);
-        }
-        // Espresso_model object
-        return static::$_instance;
-    }
-
-
-    /**
-     * resets the model and returns it
-     *
-     * @param string|null $timezone
-     * @return EEM_Base|null (if the model was already instantiated, returns it, with
-     * all its properties reset; if it wasn't instantiated, returns null)
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public static function reset($timezone = null)
-    {
-        if (! static::$_instance instanceof EEM_Base) {
-            return null;
-        }
-        // Let's NOT swap out the current instance for a new one
-        // because if someone has a reference to it, we can't remove their reference.
-        // It's best to keep using the same reference but change the original object instead,
-        // so reset all its properties to their original values as defined in the class.
-        $static_properties = EEM_Base::getMirror()->getStaticProperties(static::class);
-        foreach (EEM_Base::getMirror()->getDefaultProperties(static::class) as $property => $value) {
-            // don't set instance to null like it was originally,
-            // but it's static anyways, and we're ignoring static properties (for now at least)
-            if (! isset($static_properties[ $property ])) {
-                static::$_instance->{$property} = $value;
-            }
-        }
-        // and then directly call its constructor again, like we would if we were creating a new one
-        $arguments = EEM_Base::getModelArguments(static::class, (string) $timezone);
-        static::$_instance->__construct(...$arguments);
-        return self::instance();
-    }
-
-
-    /**
-     * Used to set the $_model_query_blog_id static property.
-     *
-     * @param int $blog_id  If provided then will set the blog_id for the models to this id.  If not provided then the
-     *                      value for get_current_blog_id() will be used.
-     */
-    public static function set_model_query_blog_id($blog_id = 0)
-    {
-        EEM_Base::$_model_query_blog_id = $blog_id > 0
-            ? (int) $blog_id
-            : get_current_blog_id();
-    }
-
-
-    /**
-     * Returns whatever is set as the internal $model_query_blog_id.
-     *
-     * @return int
-     */
-    public static function get_model_query_blog_id()
-    {
-        return EEM_Base::$_model_query_blog_id;
-    }
-
-
-    /**
-     * retrieve the status details from esp_status table as an array IF this model has the status table as a relation.
-     *
-     * @param boolean $translated return localized strings or JUST the array.
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function status_array($translated = false)
-    {
-        if (! array_key_exists('Status', $this->_model_relations)) {
-            return [];
-        }
-        $model_name   = $this->get_this_model_name();
-        $status_type  = str_replace(' ', '_', strtolower(str_replace('_', ' ', $model_name)));
-        $stati        = EEM_Status::instance()->get_all([['STS_type' => $status_type]]);
-        $status_array = [];
-        foreach ($stati as $status) {
-            $status_array[ $status->ID() ] = $status->get('STS_code');
-        }
-        return $translated
-            ? EEM_Status::instance()->localized_status($status_array, false, 'sentence')
-            : $status_array;
-    }
-
-
-    /**
-     * Gets all the EE_Base_Class objects which match the $query_params, by querying the DB.
-     *
-     * @param array $query_params             @see
-     *                                        https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     *                                        or if you have the development copy of EE you can view this at the path:
-     *                                        /docs/G--Model-System/model-query-params.md
-     * @return EE_Base_Class[]  *note that there is NO option to pass the output type. If you want results different
-     *                                        from EE_Base_Class[], use get_all_wpdb_results(). Array keys are object
-     *                                        IDs (if there is a primary key on the model. if not, numerically indexed)
-     *                                        Some full examples: get 10 transactions which have Scottish attendees:
-     *                                        EEM_Transaction::instance()->get_all( array( array(
-     *                                        'OR'=>array(
-     *                                        'Registration.Attendee.ATT_fname'=>array('like','Mc%'),
-     *                                        'Registration.Attendee.ATT_fname*other'=>array('like','Mac%')
-     *                                        )
-     *                                        ),
-     *                                        'limit'=>10,
-     *                                        'group_by'=>'TXN_ID'
-     *                                        ));
-     *                                        get all the answers to the question titled "shirt size" for event with id
-     *                                        12, ordered by their answer EEM_Answer::instance()->get_all(array( array(
-     *                                        'Question.QST_display_text'=>'shirt size',
-     *                                        'Registration.Event.EVT_ID'=>12
-     *                                        ),
-     *                                        'order_by'=>array('ANS_value'=>'ASC')
-     *                                        ));
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_all($query_params = [])
-    {
-        if (
-            isset($query_params['limit'])
-            && ! isset($query_params['group_by'])
-        ) {
-            $query_params['group_by'] = array_keys($this->get_combined_primary_key_fields());
-        }
-        return $this->_create_objects($this->_get_all_wpdb_results($query_params));
-    }
-
-
-    /**
-     * Modifies the query parameters so we only get back model objects
-     * that "belong" to the current user
-     *
-     * @param array $query_params @see
-     *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return array @see
-     *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @throws ReflectionException
-     * @throws ReflectionException
-     */
-    public function alter_query_params_to_only_include_mine($query_params = [])
-    {
-        $wp_user_field_name = $this->wp_user_field_name();
-        if ($wp_user_field_name) {
-            $query_params[0][ $wp_user_field_name ] = get_current_user_id();
-        }
-        return $query_params;
-    }
-
-
-    /**
-     * Returns the name of the field's name that points to the WP_User table
-     *  on this model (or follows the _model_chain_to_wp_user and uses that model's
-     * foreign key to the WP_User table)
-     *
-     * @return string|boolean string on success, boolean false when there is no
-     * foreign key to the WP_User table
-     * @throws ReflectionException
-     * @throws ReflectionException
-     */
-    public function wp_user_field_name()
-    {
-        try {
-            if (! empty($this->_model_chain_to_wp_user)) {
-                $models_to_follow_to_wp_users = explode('.', $this->_model_chain_to_wp_user);
-                $last_model_name              = end($models_to_follow_to_wp_users);
-                $model_with_fk_to_wp_users    = EE_Registry::instance()->load_model($last_model_name);
-                $model_chain_to_wp_user       = $this->_model_chain_to_wp_user . '.';
-            } else {
-                $model_with_fk_to_wp_users = $this;
-                $model_chain_to_wp_user    = '';
-            }
-            $wp_user_field = $model_with_fk_to_wp_users->get_foreign_key_to('WP_User');
-            return $model_chain_to_wp_user . $wp_user_field->get_name();
-        } catch (EE_Error $e) {
-            return false;
-        }
-    }
-
-
-    /**
-     * Returns the _model_chain_to_wp_user string, which indicates which related model
-     * (or transiently-related model) has a foreign key to the wp_users table;
-     * useful for finding if model objects of this type are 'owned' by the current user.
-     * This is an empty string when the foreign key is on this model and when it isn't,
-     * but is only non-empty when this model's ownership is indicated by a RELATED model
-     * (or transiently-related model)
-     *
-     * @return string
-     */
-    public function model_chain_to_wp_user()
-    {
-        return $this->_model_chain_to_wp_user;
-    }
-
-
-    /**
-     * Whether this model is 'owned' by a specific wordpress user (even indirectly,
-     * like how registrations don't have a foreign key to wp_users, but the
-     * events they are for are), or is unrelated to wp users.
-     * generally available
-     *
-     * @return boolean
-     */
-    public function is_owned()
-    {
-        if ($this->model_chain_to_wp_user()) {
-            return true;
-        }
-        try {
-            $this->get_foreign_key_to('WP_User');
-            return true;
-        } catch (EE_Error $e) {
-            return false;
-        }
-    }
-
-
-    /**
-     * Used internally to get WPDB results, because other functions, besides get_all, may want to do some queries, but
-     * may want to preserve the WPDB results (eg, update, which first queries to make sure we have all the tables on
-     * the model)
-     *
-     * @param array  $query_params      @see
-     *                                  https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $output            ARRAY_A, OBJECT_K, etc. Just like
-     * @param mixed  $columns_to_select , What columns to select. By default, we select all columns specified by the
-     *                                  fields on the model, and the models we joined to in the query. However, you can
-     *                                  override this and set the select to "*", or a specific column name, like
-     *                                  "ATT_ID", etc. If you would like to use these custom selections in WHERE,
-     *                                  GROUP_BY, or HAVING clauses, you must instead provide an array. Array keys are
-     *                                  the aliases used to refer to this selection, and values are to be
-     *                                  numerically-indexed arrays, where 0 is the selection and 1 is the data type.
-     *                                  Eg, array('count'=>array('COUNT(REG_ID)','%d'))
-     * @return array | stdClass[] like results of $wpdb->get_results($sql,OBJECT), (ie, output type is OBJECT)
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     */
-    protected function _get_all_wpdb_results($query_params = [], $output = ARRAY_A, $columns_to_select = null)
-    {
-        $this->_custom_selections = $this->getCustomSelection($query_params, $columns_to_select);
-        $model_query_info         = $this->_create_model_query_info_carrier($query_params);
-        $select_expressions       = $columns_to_select === null
-            ? $this->_construct_default_select_sql($model_query_info)
-            : '';
-        if ($this->_custom_selections instanceof CustomSelects) {
-            $custom_expressions = $this->_custom_selections->columnsToSelectExpression();
-            $select_expressions .= $select_expressions
-                ? ', ' . $custom_expressions
-                : $custom_expressions;
-        }
-
-        $SQL = "SELECT $select_expressions " . $this->_construct_2nd_half_of_select_query($model_query_info);
-        return $this->_do_wpdb_query('get_results', [$SQL, $output]);
-    }
-
-
-    /**
-     * Get a CustomSelects object if the $query_params or $columns_to_select allows for it.
-     * Note: $query_params['extra_selects'] will always override any $columns_to_select values. It is the preferred
-     * method of including extra select information.
-     *
-     * @param array             $query_params
-     * @param null|array|string $columns_to_select
-     * @return null|CustomSelects
-     * @throws InvalidArgumentException
-     */
-    protected function getCustomSelection(array $query_params, $columns_to_select = null)
-    {
-        if (! isset($query_params['extra_selects']) && $columns_to_select === null) {
-            return null;
-        }
-        $selects = isset($query_params['extra_selects']) ? $query_params['extra_selects'] : $columns_to_select;
-        $selects = is_string($selects) ? explode(',', $selects) : $selects;
-        return new CustomSelects($selects);
-    }
-
-
-    /**
-     * Gets an array of rows from the database just like $wpdb->get_results would,
-     * but you can use the model query params to more easily
-     * take care of joins, field preparation etc.
-     *
-     * @param array  $query_params      @see
-     *                                  https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $output            ARRAY_A, OBJECT_K, etc. Just like
-     * @param mixed  $columns_to_select , What columns to select. By default, we select all columns specified by the
-     *                                  fields on the model, and the models we joined to in the query. However, you can
-     *                                  override this and set the select to "*", or a specific column name, like
-     *                                  "ATT_ID", etc. If you would like to use these custom selections in WHERE,
-     *                                  GROUP_BY, or HAVING clauses, you must instead provide an array. Array keys are
-     *                                  the aliases used to refer to this selection, and values are to be
-     *                                  numerically-indexed arrays, where 0 is the selection and 1 is the data type.
-     *                                  Eg, array('count'=>array('COUNT(REG_ID)','%d'))
-     * @return array|stdClass[] like results of $wpdb->get_results($sql,OBJECT), (ie, output type is OBJECT)
-     * @throws EE_Error
-     */
-    public function get_all_wpdb_results($query_params = [], $output = ARRAY_A, $columns_to_select = null)
-    {
-        return $this->_get_all_wpdb_results($query_params, $output, $columns_to_select);
-    }
-
-
-    /**
-     * For creating a custom select statement
-     *
-     * @param mixed $columns_to_select either a string to be inserted directly as the select statement,
-     *                                 or an array where keys are aliases, and values are arrays where 0=>the selection
-     *                                 SQL, and 1=>is the datatype
-     * @return string
-     * @throws EE_Error
-     */
-    private function _construct_select_from_input($columns_to_select)
-    {
-        if (is_array($columns_to_select)) {
-            $select_sql_array = [];
-            foreach ($columns_to_select as $alias => $selection_and_datatype) {
-                if (! is_array($selection_and_datatype) || ! isset($selection_and_datatype[1])) {
-                    throw new EE_Error(
-                        sprintf(
-                            esc_html__(
-                                "Custom selection %s (alias %s) needs to be an array like array('COUNT(REG_ID)','%%d')",
-                                'event_espresso'
-                            ),
-                            $selection_and_datatype,
-                            $alias
-                        )
-                    );
-                }
-                if (! in_array($selection_and_datatype[1], $this->_valid_wpdb_data_types, true)) {
-                    throw new EE_Error(
-                        sprintf(
-                            esc_html__(
-                                "Datatype %s (for selection '%s' and alias '%s') is not a valid wpdb datatype (eg %%s)",
-                                'event_espresso'
-                            ),
-                            $selection_and_datatype[1],
-                            $selection_and_datatype[0],
-                            $alias,
-                            implode(', ', $this->_valid_wpdb_data_types)
-                        )
-                    );
-                }
-                $select_sql_array[] = "{$selection_and_datatype[0]} AS $alias";
-            }
-            $columns_to_select_string = implode(', ', $select_sql_array);
-        } else {
-            $columns_to_select_string = $columns_to_select;
-        }
-        return $columns_to_select_string;
-    }
-
-
-    /**
-     * Convenient wrapper for getting the primary key field's name. Eg, on Registration, this would be 'REG_ID'
-     *
-     * @return string
-     * @throws EE_Error
-     */
-    public function primary_key_name()
-    {
-        return $this->get_primary_key_field()->get_name();
-    }
-
-
-    /**
-     * Gets a single item for this model from the DB, given only its ID (or null if none is found).
-     * If there is no primary key on this model, $id is treated as primary key string
-     *
-     * @param mixed $id int or string, depending on the type of the model's primary key
-     * @return EE_Base_Class|mixed|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_one_by_ID($id)
-    {
-        if ($this->get_from_entity_map($id)) {
-            return $this->get_from_entity_map($id);
-        }
-        $model_object = $this->get_one(
-            $this->alter_query_params_to_restrict_by_ID(
-                $id,
-                ['default_where_conditions' => EEM_Base::default_where_conditions_minimum_all]
-            )
-        );
-        $className    = $this->_get_class_name();
-        if ($model_object instanceof $className) {
-            // make sure valid objects get added to the entity map
-            // so that the next call to this method doesn't trigger another trip to the db
-            $this->add_to_entity_map($model_object);
-        }
-        return $model_object;
-    }
-
-
-    /**
-     * Alters query parameters to only get items with this ID are returned.
-     * Takes into account that the ID might be a string produced by EEM_Base::get_index_primary_key_string(),
-     * or could just be a simple primary key ID
-     *
-     * @param int   $id
-     * @param array $query_params
-     * @return array of normal query params, @see
-     *               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @throws EE_Error
-     */
-    public function alter_query_params_to_restrict_by_ID($id, $query_params = [])
-    {
-        if (! isset($query_params[0])) {
-            $query_params[0] = [];
-        }
-        $conditions_from_id = $this->parse_index_primary_key_string($id);
-        if ($conditions_from_id === null) {
-            $query_params[0][ $this->primary_key_name() ] = $id;
-        } else {
-            // no primary key, so the $id must be from the get_index_primary_key_string()
-            $query_params[0] = array_replace_recursive($query_params[0], $this->parse_index_primary_key_string($id));
-        }
-        return $query_params;
-    }
-
-
-    /**
-     * Gets a single item for this model from the DB, given the $query_params. Only returns a single class, not an
-     * array. If no item is found, null is returned.
-     *
-     * @param array $query_params like EEM_Base's $query_params variable.
-     * @return EE_Base_Class|EE_Soft_Delete_Base_Class|NULL
-     * @throws EE_Error
-     */
-    public function get_one($query_params = [])
-    {
-        if (! is_array($query_params)) {
-            EE_Error::doing_it_wrong(
-                'EEM_Base::get_one',
-                sprintf(
-                    esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
-                    gettype($query_params)
-                ),
-                '4.6.0'
-            );
-            $query_params = [];
-        }
-        $query_params['limit'] = 1;
-        $items                 = $this->get_all($query_params);
-        if (empty($items)) {
-            return null;
-        }
-        return array_shift($items);
-    }
-
-
-    /**
-     * Returns the next x number of items in sequence from the given value as
-     * found in the database matching the given query conditions.
-     *
-     * @param mixed $current_field_value    Value used for the reference point.
-     * @param null  $field_to_order_by      What field is used for the
-     *                                      reference point.
-     * @param int   $limit                  How many to return.
-     * @param array $query_params           Extra conditions on the query.
-     * @param null  $columns_to_select      If left null, then an array of
-     *                                      EE_Base_Class objects is returned,
-     *                                      otherwise you can indicate just the
-     *                                      columns you want returned.
-     * @return EE_Base_Class[]|array
-     * @throws EE_Error
-     */
-    public function next_x(
-        $current_field_value,
-        $field_to_order_by = null,
-        $limit = 1,
-        $query_params = [],
-        $columns_to_select = null
-    ) {
-        return $this->_get_consecutive(
-            $current_field_value,
-            '>',
-            $field_to_order_by,
-            $limit,
-            $query_params,
-            $columns_to_select
-        );
-    }
-
-
-    /**
-     * Returns the previous x number of items in sequence from the given value
-     * as found in the database matching the given query conditions.
-     *
-     * @param mixed $current_field_value    Value used for the reference point.
-     * @param null  $field_to_order_by      What field is used for the
-     *                                      reference point.
-     * @param int   $limit                  How many to return.
-     * @param array $query_params           Extra conditions on the query.
-     * @param null  $columns_to_select      If left null, then an array of
-     *                                      EE_Base_Class objects is returned,
-     *                                      otherwise you can indicate just the
-     *                                      columns you want returned.
-     * @return EE_Base_Class[]|array
-     * @throws EE_Error
-     */
-    public function previous_x(
-        $current_field_value,
-        $field_to_order_by = null,
-        $limit = 1,
-        $query_params = [],
-        $columns_to_select = null
-    ) {
-        return $this->_get_consecutive(
-            $current_field_value,
-            '<',
-            $field_to_order_by,
-            $limit,
-            $query_params,
-            $columns_to_select
-        );
-    }
-
-
-    /**
-     * Returns the next item in sequence from the given value as found in the
-     * database matching the given query conditions.
-     *
-     * @param mixed $current_field_value    Value used for the reference point.
-     * @param null  $field_to_order_by      What field is used for the
-     *                                      reference point.
-     * @param array $query_params           Extra conditions on the query.
-     * @param null  $columns_to_select      If left null, then an EE_Base_Class
-     *                                      object is returned, otherwise you
-     *                                      can indicate just the columns you
-     *                                      want and a single array indexed by
-     *                                      the columns will be returned.
-     * @return EE_Base_Class|null|array()
-     * @throws EE_Error
-     */
-    public function next(
-        $current_field_value,
-        $field_to_order_by = null,
-        $query_params = [],
-        $columns_to_select = null
-    ) {
-        $results = $this->_get_consecutive(
-            $current_field_value,
-            '>',
-            $field_to_order_by,
-            1,
-            $query_params,
-            $columns_to_select
-        );
-        return empty($results) ? null : reset($results);
-    }
-
-
-    /**
-     * Returns the previous item in sequence from the given value as found in
-     * the database matching the given query conditions.
-     *
-     * @param mixed $current_field_value    Value used for the reference point.
-     * @param null  $field_to_order_by      What field is used for the
-     *                                      reference point.
-     * @param array $query_params           Extra conditions on the query.
-     * @param null  $columns_to_select      If left null, then an EE_Base_Class
-     *                                      object is returned, otherwise you
-     *                                      can indicate just the columns you
-     *                                      want and a single array indexed by
-     *                                      the columns will be returned.
-     * @return EE_Base_Class|null|array()
-     * @throws EE_Error
-     */
-    public function previous(
-        $current_field_value,
-        $field_to_order_by = null,
-        $query_params = [],
-        $columns_to_select = null
-    ) {
-        $results = $this->_get_consecutive(
-            $current_field_value,
-            '<',
-            $field_to_order_by,
-            1,
-            $query_params,
-            $columns_to_select
-        );
-        return empty($results) ? null : reset($results);
-    }
-
-
-    /**
-     * Returns the a consecutive number of items in sequence from the given
-     * value as found in the database matching the given query conditions.
-     *
-     * @param mixed  $current_field_value   Value used for the reference point.
-     * @param string $operand               What operand is used for the sequence.
-     * @param string $field_to_order_by     What field is used for the reference point.
-     * @param int    $limit                 How many to return.
-     * @param array  $query_params          Extra conditions on the query.
-     * @param null   $columns_to_select     If left null, then an array of EE_Base_Class objects is returned,
-     *                                      otherwise you can indicate just the columns you want returned.
-     * @return EE_Base_Class[]|array
-     * @throws EE_Error
-     */
-    protected function _get_consecutive(
-        $current_field_value,
-        $operand = '>',
-        $field_to_order_by = null,
-        $limit = 1,
-        $query_params = [],
-        $columns_to_select = null
-    ) {
-        // if $field_to_order_by is empty then let's assume we're ordering by the primary key.
-        if (empty($field_to_order_by)) {
-            if ($this->has_primary_key_field()) {
-                $field_to_order_by = $this->get_primary_key_field()->get_name();
-            } else {
-                if (WP_DEBUG) {
-                    throw new EE_Error(
-                        esc_html__(
-                            'EEM_Base::_get_consecutive() has been called with no $field_to_order_by argument and there is no primary key on the field.  Please provide the field you would like to use as the base for retrieving the next item(s).',
-                            'event_espresso'
-                        )
-                    );
-                }
-                EE_Error::add_error(
-                    esc_html__('There was an error with the query.', 'event_espresso'),
-                    __FILE__,
-                    __FUNCTION__,
-                    __LINE__
-                );
-                return [];
-            }
-        }
-        if (! is_array($query_params)) {
-            EE_Error::doing_it_wrong(
-                'EEM_Base::_get_consecutive',
-                sprintf(
-                    esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
-                    gettype($query_params)
-                ),
-                '4.6.0'
-            );
-            $query_params = [];
-        }
-        // let's add the where query param for consecutive look up.
-        $query_params[0][ $field_to_order_by ] = [$operand, $current_field_value];
-        $query_params['limit']                 = $limit;
-        // set direction
-        $incoming_orderby         = isset($query_params['order_by']) ? (array) $query_params['order_by'] : [];
-        $query_params['order_by'] = $operand === '>'
-            ? [$field_to_order_by => 'ASC'] + $incoming_orderby
-            : [$field_to_order_by => 'DESC'] + $incoming_orderby;
-        // if $columns_to_select is empty then that means we're returning EE_Base_Class objects
-        if (empty($columns_to_select)) {
-            return $this->get_all($query_params);
-        }
-        // getting just the fields
-        return $this->_get_all_wpdb_results($query_params, ARRAY_A, $columns_to_select);
-    }
-
-
-    /**
-     * This sets the _timezone property after model object has been instantiated.
-     *
-     * @param null | string $timezone valid PHP DateTimeZone timezone string
-     */
-    public function set_timezone($timezone)
-    {
-        if ($timezone !== null) {
-            $this->_timezone = $timezone;
-        }
-        // note we need to loop through relations and set the timezone on those objects as well.
-        foreach ($this->_model_relations as $relation) {
-            $relation->set_timezone($timezone);
-        }
-        // and finally we do the same for any datetime fields
-        foreach ($this->_fields as $field) {
-            if ($field instanceof EE_Datetime_Field) {
-                $field->set_timezone($timezone);
-            }
-        }
-    }
-
-
-    /**
-     * This just returns whatever is set for the current timezone.
-     *
-     * @access public
-     * @return string
-     */
-    public function get_timezone()
-    {
-        // first validate if timezone is set.  If not, then let's set it be whatever is set on the model fields.
-        if (empty($this->_timezone)) {
-            foreach ($this->_fields as $field) {
-                if ($field instanceof EE_Datetime_Field) {
-                    $this->set_timezone($field->get_timezone());
-                    break;
-                }
-            }
-        }
-        // if timezone STILL empty then return the default timezone for the site.
-        if (empty($this->_timezone)) {
-            $this->set_timezone(EEH_DTT_Helper::get_timezone());
-        }
-        return $this->_timezone;
-    }
-
-
-    /**
-     * This returns the date formats set for the given field name and also ensures that
-     * $this->_timezone property is set correctly.
-     *
-     * @param string $field_name The name of the field the formats are being retrieved for.
-     * @param bool   $pretty     Whether to return the pretty formats (true) or not (false).
-     * @return array formats in an array with the date format first, and the time format last.
-     * @throws EE_Error   If the given field_name is not of the EE_Datetime_Field type.
-     * @since 4.6.x
-     */
-    public function get_formats_for($field_name, $pretty = false)
-    {
-        $field_settings = $this->field_settings_for($field_name);
-        // if not a valid EE_Datetime_Field then throw error
-        if (! $field_settings instanceof EE_Datetime_Field) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'The field sent into EEM_Base::get_formats_for (%s) is not registered as a EE_Datetime_Field. Please check the spelling and make sure you are submitting the right field name to retrieve date_formats for.',
-                        'event_espresso'
-                    ),
-                    $field_name
-                )
-            );
-        }
-        // while we are here, let's make sure the timezone internally in EEM_Base matches what is stored on
-        // the field.
-        $this->_timezone = $field_settings->get_timezone();
-        return [$field_settings->get_date_format($pretty), $field_settings->get_time_format($pretty)];
-    }
-
-
-    /**
-     * This returns the current time in a format setup for a query on this model.
-     * Usage of this method makes it easier to setup queries against EE_Datetime_Field columns because
-     * it will return:
-     *  - a formatted string in the timezone and format currently set on the EE_Datetime_Field for the given field for
-     *  NOW
-     *  - or a unix timestamp (equivalent to time())
-     * Note: When requesting a formatted string, if the date or time format doesn't include seconds, for example,
-     * the time returned, because it uses that format, will also NOT include seconds. For this reason, if you want
-     * the time returned to be the current time down to the exact second, set $timestamp to true.
-     *
-     * @param string $field_name       The field the current time is needed for.
-     * @param bool   $timestamp        True means to return a unix timestamp. Otherwise a
-     *                                 formatted string matching the set format for the field in the set timezone will
-     *                                 be returned.
-     * @param string $what             Whether to return the string in just the time format, the date format, or both.
-     * @return int|string  If the given field_name is not of the EE_Datetime_Field type, then an EE_Error
-     *                                 exception is triggered.
-     * @throws EE_Error    If the given field_name is not of the EE_Datetime_Field type.
-     * @throws Exception
-     * @since 4.6.x
-     */
-    public function current_time_for_query($field_name, $timestamp = false, $what = 'both')
-    {
-        $formats  = $this->get_formats_for($field_name);
-        $DateTime = new DateTime("now", new DateTimeZone($this->_timezone));
-        if ($timestamp) {
-            return $DateTime->format('U');
-        }
-        // not returning timestamp, so return formatted string in timezone.
-        switch ($what) {
-            case 'time':
-                return $DateTime->format($formats[1]);
-            case 'date':
-                return $DateTime->format($formats[0]);
-            default:
-                return $DateTime->format(implode(' ', $formats));
-        }
-    }
-
-
-    /**
-     * This receives a time string for a given field and ensures that it is setup to match what the internal settings
-     * for the model are.  Returns a DateTime object.
-     * Note: a gotcha for when you send in unix timestamp.  Remember a unix timestamp is already timezone agnostic,
-     * (functionally the equivalent of UTC+0).  So when you send it in, whatever timezone string you include is
-     * ignored.
-     *
-     * @param string $field_name      The field being setup.
-     * @param string $timestring      The date time string being used.
-     * @param string $incoming_format The format for the time string.
-     * @param string $timezone        By default, it is assumed the incoming time string is in timezone for
-     *                                the blog.  If this is not the case, then it can be specified here.  If incoming
-     *                                format is
-     *                                'U', this is ignored.
-     * @return DateTime
-     * @throws EE_Error
-     */
-    public function convert_datetime_for_query($field_name, $timestring, $incoming_format, $timezone = '')
-    {
-        // just using this to ensure the timezone is set correctly internally
-        $this->get_formats_for($field_name);
-        // load EEH_DTT_Helper
-        $set_timezone     = empty($timezone) ? EEH_DTT_Helper::get_timezone() : $timezone;
-        $incomingDateTime = date_create_from_format($incoming_format, $timestring, new DateTimeZone($set_timezone));
-        EEH_DTT_Helper::setTimezone($incomingDateTime, new DateTimeZone($this->_timezone));
-        return \EventEspresso\core\domain\entities\DbSafeDateTime::createFromDateTime($incomingDateTime);
-    }
-
-
-    /**
-     * Gets all the tables comprising this model. Array keys are the table aliases, and values are EE_Table objects
-     *
-     * @return EE_Table_Base[]
-     */
-    public function get_tables()
-    {
-        return $this->_tables;
-    }
-
-
-    /**
-     * Updates all the database entries (in each table for this model) according to $fields_n_values and optionally
-     * also updates all the model objects, where the criteria expressed in $query_params are met..
-     * Also note: if this model has multiple tables, this update verifies all the secondary tables have an entry for
-     * each row (in the primary table) we're trying to update; if not, it inserts an entry in the secondary table. Eg:
-     * if our model has 2 tables: wp_posts (primary), and wp_esp_event (secondary). Let's say we are trying to update a
-     * model object with EVT_ID = 1
-     * (which means where wp_posts has ID = 1, because wp_posts.ID is the primary key's column), which exists, but
-     * there is no entry in wp_esp_event for this entry in wp_posts. So, this update script will insert a row into
-     * wp_esp_event, using any available parameters from $fields_n_values (eg, if "EVT_limit" => 40 is in
-     * $fields_n_values, the new entry in wp_esp_event will set EVT_limit = 40, and use default for other columns which
-     * are not specified)
-     *
-     * @param array   $fields_n_values         keys are model fields (exactly like keys in EEM_Base::_fields, NOT db
-     *                                         columns!), values are strings, ints, floats, and maybe arrays if they
-     *                                         are to be serialized. Basically, the values are what you'd expect to be
-     *                                         values on the model, NOT necessarily what's in the DB. For example, if
-     *                                         we wanted to update only the TXN_details on any Transactions where its
-     *                                         ID=34, we'd use this method as follows:
-     *                                         EEM_Transaction::instance()->update(
-     *                                         array('TXN_details'=>array('detail1'=>'monkey','detail2'=>'banana'),
-     *                                         array(array('TXN_ID'=>34)));
-     * @param array   $query_params            @see
-     *                                         https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     *                                         Eg, consider updating Question's QST_admin_label field is of type
-     *                                         Simple_HTML. If you use this function to update that field to $new_value
-     *                                         = (note replace 8's with appropriate opening and closing tags in the
-     *                                         following example)"8script8alert('I hack all');8/script88b8boom
-     *                                         baby8/b8", then if you set $values_already_prepared_by_model_object to
-     *                                         TRUE, it is assumed that you've already called
-     *                                         EE_Simple_HTML_Field->prepare_for_set($new_value), which removes the
-     *                                         malicious javascript. However, if
-     *                                         $values_already_prepared_by_model_object is left as FALSE, then
-     *                                         EE_Simple_HTML_Field->prepare_for_set($new_value) will be called on it,
-     *                                         and every other field, before insertion. We provide this parameter
-     *                                         because model objects perform their prepare_for_set function on all
-     *                                         their values, and so don't need to be called again (and in many cases,
-     *                                         shouldn't be called again. Eg: if we escape HTML characters in the
-     *                                         prepare_for_set method...)
-     * @param boolean $keep_model_objs_in_sync if TRUE, makes sure we ALSO update model objects
-     *                                         in this model's entity map according to $fields_n_values that match
-     *                                         $query_params. This obviously has some overhead, so you can disable it
-     *                                         by setting this to FALSE, but be aware that model objects being used
-     *                                         could get out-of-sync with the database
-     * @return int how many rows got updated or FALSE if something went wrong with the query (wp returns FALSE or num
-     *                                         rows affected which *could* include 0 which DOES NOT mean the query was
-     *                                         bad)
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function update($fields_n_values, $query_params, $keep_model_objs_in_sync = true)
-    {
-        if (! is_array($query_params)) {
-            EE_Error::doing_it_wrong(
-                'EEM_Base::update',
-                sprintf(
-                    esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
-                    gettype($query_params)
-                ),
-                '4.6.0'
-            );
-            $query_params = [];
-        }
-        /**
-         * Action called before a model update call has been made.
-         *
-         * @param EEM_Base $model
-         * @param array    $fields_n_values the updated fields and their new values
-         * @param array    $query_params    @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-         */
-        do_action('AHEE__EEM_Base__update__begin', $this, $fields_n_values, $query_params);
-        /**
-         * Filters the fields about to be updated given the query parameters. You can provide the
-         * $query_params to $this->get_all() to find exactly which records will be updated
-         *
-         * @param array    $fields_n_values fields and their new values
-         * @param EEM_Base $model           the model being queried
-         * @param array    $query_params    @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-         */
-        $fields_n_values = (array) apply_filters(
-            'FHEE__EEM_Base__update__fields_n_values',
-            $fields_n_values,
-            $this,
-            $query_params
-        );
-        // need to verify that, for any entry we want to update, there are entries in each secondary table.
-        // to do that, for each table, verify that it's PK isn't null.
-        $tables = $this->get_tables();
-        // and if the other tables don't have a row for each table-to-be-updated, we'll insert one with whatever values available in the current update query
-        // NOTE: we should make this code more efficient by NOT querying twice
-        // before the real update, but that needs to first go through ALPHA testing
-        // as it's dangerous. says Mike August 8 2014
-        // we want to make sure the default_where strategy is ignored
-        $this->_ignore_where_strategy = true;
-        $wpdb_select_results          = $this->_get_all_wpdb_results($query_params);
-        foreach ($wpdb_select_results as $wpdb_result) {
-            // type cast stdClass as array
-            $wpdb_result = (array) $wpdb_result;
-            // get the model object's PK, as we'll want this if we need to insert a row into secondary tables
-            if ($this->has_primary_key_field()) {
-                $main_table_pk_value = $wpdb_result[ $this->get_primary_key_field()->get_qualified_column() ];
-            } else {
-                // if there's no primary key, we basically can't support having a 2nd table on the model (we could but it would be lots of work)
-                $main_table_pk_value = null;
-            }
-            // if there are more than 1 tables, we'll want to verify that each table for this model has an entry in the other tables
-            // and if the other tables don't have a row for each table-to-be-updated, we'll insert one with whatever values available in the current update query
-            if (count($tables) > 1) {
-                // foreach matching row in the DB, ensure that each table's PK isn't null. If so, there must not be an entry
-                // in that table, and so we'll want to insert one
-                foreach ($tables as $table_obj) {
-                    $this_table_pk_column = $table_obj->get_fully_qualified_pk_column();
-                    // if there is no private key for this table on the results, it means there's no entry
-                    // in this table, right? so insert a row in the current table, using any fields available
-                    if (
-                        ! (array_key_exists($this_table_pk_column, $wpdb_result)
-                           && $wpdb_result[ $this_table_pk_column ])
-                    ) {
-                        $success = $this->_insert_into_specific_table(
-                            $table_obj,
-                            $fields_n_values,
-                            $main_table_pk_value
-                        );
-                        // if we died here, report the error
-                        if (! $success) {
-                            return false;
-                        }
-                    }
-                }
-            }
-            //              //and now check that if we have cached any models by that ID on the model, that
-            //              //they also get updated properly
-            //              $model_object = $this->get_from_entity_map( $main_table_pk_value );
-            //              if( $model_object ){
-            //                  foreach( $fields_n_values as $field => $value ){
-            //                      $model_object->set($field, $value);
-            // let's make sure default_where strategy is followed now
-            $this->_ignore_where_strategy = false;
-        }
-        // if we want to keep model objects in sync, AND
-        // if this wasn't called from a model object (to update itself)
-        // then we want to make sure we keep all the existing
-        // model objects in sync with the db
-        if ($keep_model_objs_in_sync && ! $this->_values_already_prepared_by_model_object) {
-            if ($this->has_primary_key_field()) {
-                $model_objs_affected_ids = $this->get_col($query_params);
-            } else {
-                // we need to select a bunch of columns and then combine them into the the "index primary key string"s
-                $models_affected_key_columns = $this->_get_all_wpdb_results($query_params, ARRAY_A);
-                $model_objs_affected_ids     = [];
-                foreach ($models_affected_key_columns as $row) {
-                    $combined_index_key                             = $this->get_index_primary_key_string($row);
-                    $model_objs_affected_ids[ $combined_index_key ] = $combined_index_key;
-                }
-            }
-            if (! $model_objs_affected_ids) {
-                // wait wait wait- if nothing was affected let's stop here
-                return 0;
-            }
-            foreach ($model_objs_affected_ids as $id) {
-                $model_obj_in_entity_map = $this->get_from_entity_map($id);
-                if ($model_obj_in_entity_map) {
-                    foreach ($fields_n_values as $field => $new_value) {
-                        $model_obj_in_entity_map->set($field, $new_value);
-                    }
-                }
-            }
-            // if there is a primary key on this model, we can now do a slight optimization
-            if ($this->has_primary_key_field()) {
-                // we already know what we want to update. So let's make the query simpler so it's a little more efficient
-                $query_params = [
-                    [$this->primary_key_name() => ['IN', $model_objs_affected_ids]],
-                    'limit'                    => count($model_objs_affected_ids),
-                    'default_where_conditions' => EEM_Base::default_where_conditions_none,
-                ];
-            }
-        }
-        $model_query_info = $this->_create_model_query_info_carrier($query_params);
-        $SQL              = "UPDATE "
-                            . $model_query_info->get_full_join_sql()
-                            . " SET "
-                            . $this->_construct_update_sql($fields_n_values)
-                            . $model_query_info->get_where_sql(
-                            );// note: doesn't use _construct_2nd_half_of_select_query() because doesn't accept LIMIT, ORDER BY, etc.
-        $rows_affected    = $this->_do_wpdb_query('query', [$SQL]);
-        /**
-         * Action called after a model update call has been made.
-         *
-         * @param EEM_Base $model
-         * @param array    $fields_n_values the updated fields and their new values
-         * @param array    $query_params    @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-         * @param int      $rows_affected
-         */
-        do_action('AHEE__EEM_Base__update__end', $this, $fields_n_values, $query_params, $rows_affected);
-        return $rows_affected;// how many supposedly got updated
-    }
-
-
-    /**
-     * Analogous to $wpdb->get_col, returns a 1-dimensional array where teh values
-     * are teh values of the field specified (or by default the primary key field)
-     * that matched the query params. Note that you should pass the name of the
-     * model FIELD, not the database table's column name.
-     *
-     * @param array  $query_params @see
-     *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_select
-     * @return array just like $wpdb->get_col()
-     * @throws EE_Error
-     */
-    public function get_col($query_params = [], $field_to_select = null)
-    {
-        if ($field_to_select) {
-            $field = $this->field_settings_for($field_to_select);
-        } elseif ($this->has_primary_key_field()) {
-            $field = $this->get_primary_key_field();
-        } else {
-            $field_settings = $this->field_settings();
-            // no primary key, just grab the first column
-            $field = reset($field_settings);
-            // don't need this array now
-            unset($field_settings);
-        }
-        $model_query_info   = $this->_create_model_query_info_carrier($query_params);
-        $select_expressions = $field->get_qualified_column();
-        $SQL                =
-            "SELECT $select_expressions " . $this->_construct_2nd_half_of_select_query($model_query_info);
-        return $this->_do_wpdb_query('get_col', [$SQL]);
-    }
-
-
-    /**
-     * Returns a single column value for a single row from the database
-     *
-     * @param array  $query_params    @see
-     *                                https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_select @see EEM_Base::get_col()
-     * @return string
-     * @throws EE_Error
-     */
-    public function get_var($query_params = [], $field_to_select = null)
-    {
-        $query_params['limit'] = 1;
-        $col                   = $this->get_col($query_params, $field_to_select);
-        if (! empty($col)) {
-            return reset($col);
-        }
-        return null;
-    }
-
-
-    /**
-     * Makes the SQL for after "UPDATE table_X inner join table_Y..." and before "...WHERE". Eg "Question.name='party
-     * time?', Question.desc='what do you think?',..." Values are filtered through wpdb->prepare to avoid against SQL
-     * injection, but currently no further filtering is done
-     *
-     * @param array $fields_n_values array keys are field names on this model, and values are what those fields should
-     *                               be updated to in the DB
-     * @return string of SQL
-     * @throws EE_Error
-     * @global      $wpdb
-     */
-    public function _construct_update_sql($fields_n_values)
-    {
-        /** @type WPDB $wpdb */
-        global $wpdb;
-        $cols_n_values = [];
-        foreach ($fields_n_values as $field_name => $value) {
-            $field_obj = $this->field_settings_for($field_name);
-            // if the value is NULL, we want to assign the value to that.
-            // wpdb->prepare doesn't really handle that properly
-            $prepared_value  = $this->_prepare_value_or_use_default($field_obj, $fields_n_values);
-            $value_sql       = $prepared_value === null ? 'NULL'
-                : $wpdb->prepare($field_obj->get_wpdb_data_type(), $prepared_value);
-            $cols_n_values[] = $field_obj->get_qualified_column() . "=" . $value_sql;
-        }
-        return implode(",", $cols_n_values);
-    }
-
-
-    /**
-     * Deletes a single row from the DB given the model object's primary key value. (eg, EE_Attendee->ID()'s value).
-     * Performs a HARD delete, meaning the database row should always be removed,
-     * not just have a flag field on it switched
-     * Wrapper for EEM_Base::delete_permanently()
-     *
-     * @param mixed   $id
-     * @param boolean $allow_blocking
-     * @return int the number of rows deleted
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function delete_permanently_by_ID($id, $allow_blocking = true)
-    {
-        return $this->delete_permanently(
-            [
-                [$this->get_primary_key_field()->get_name() => $id],
-                'limit' => 1,
-            ],
-            $allow_blocking
-        );
-    }
-
-
-    /**
-     * Deletes a single row from the DB given the model object's primary key value. (eg, EE_Attendee->ID()'s value).
-     * Wrapper for EEM_Base::delete()
-     *
-     * @param mixed   $id
-     * @param boolean $allow_blocking
-     * @return int the number of rows deleted
-     * @throws EE_Error
-     */
-    public function delete_by_ID($id, $allow_blocking = true)
-    {
-        return $this->delete(
-            [
-                [$this->get_primary_key_field()->get_name() => $id],
-                'limit' => 1,
-            ],
-            $allow_blocking
-        );
-    }
-
-
-    /**
-     * Identical to delete_permanently, but does a "soft" delete if possible,
-     * meaning if the model has a field that indicates its been "trashed" or
-     * "soft deleted", we will just set that instead of actually deleting the rows.
-     *
-     * @param array   $query_params
-     * @param boolean $allow_blocking
-     * @return int how many rows got deleted
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see EEM_Base::delete_permanently
-     */
-    public function delete($query_params, $allow_blocking = true)
-    {
-        return $this->delete_permanently($query_params, $allow_blocking);
-    }
-
-
-    /**
-     * Deletes the model objects that meet the query params. Note: this method is overridden
-     * in EEM_Soft_Delete_Base so that soft-deleted model objects are instead only flagged
-     * as archived, not actually deleted
-     *
-     * @param array   $query_params   @see
-     *                                https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param boolean $allow_blocking if TRUE, matched objects will only be deleted if there is no related model info
-     *                                that blocks it (ie, there' sno other data that depends on this data); if false,
-     *                                deletes regardless of other objects which may depend on it. Its generally
-     *                                advisable to always leave this as TRUE, otherwise you could easily corrupt your
-     *                                DB
-     * @return int how many rows got deleted
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function delete_permanently($query_params, $allow_blocking = true)
-    {
-        /**
-         * Action called just before performing a real deletion query. You can use the
-         * model and its $query_params to find exactly which items will be deleted
-         *
-         * @param EEM_Base $model
-         * @param array    $query_params   @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-         * @param boolean  $allow_blocking whether or not to allow related model objects
-         *                                 to block (prevent) this deletion
-         */
-        do_action('AHEE__EEM_Base__delete__begin', $this, $query_params, $allow_blocking);
-        // some MySQL databases may be running safe mode, which may restrict
-        // deletion if there is no KEY column used in the WHERE statement of a deletion.
-        // to get around this, we first do a SELECT, get all the IDs, and then run another query
-        // to delete them
-        $items_for_deletion           = $this->_get_all_wpdb_results($query_params);
-        $columns_and_ids_for_deleting = $this->_get_ids_for_delete($items_for_deletion, $allow_blocking);
-        $deletion_where_query_part    = $this->_build_query_part_for_deleting_from_columns_and_values(
-            $columns_and_ids_for_deleting
-        );
-        /**
-         * Allows client code to act on the items being deleted before the query is actually executed.
-         *
-         * @param EEM_Base $this                            The model instance being acted on.
-         * @param array    $query_params                    The incoming array of query parameters influencing what gets deleted.
-         * @param bool     $allow_blocking                  @see param description in method phpdoc block.
-         * @param array    $columns_and_ids_for_deleting    An array indicating what entities will get removed as
-         *                                                  derived from the incoming query parameters.
-         * @see details on the structure of this array in the phpdocs
-         *                                                  for the `_get_ids_for_delete_method`
-         *
-         */
-        do_action(
-            'AHEE__EEM_Base__delete__before_query',
-            $this,
-            $query_params,
-            $allow_blocking,
-            $columns_and_ids_for_deleting
-        );
-        if ($deletion_where_query_part) {
-            $model_query_info = $this->_create_model_query_info_carrier($query_params);
-            $table_aliases    = array_keys($this->_tables);
-            $SQL              = "DELETE "
-                                . implode(", ", $table_aliases)
-                                . " FROM "
-                                . $model_query_info->get_full_join_sql()
-                                . " WHERE "
-                                . $deletion_where_query_part;
-            $rows_deleted     = $this->_do_wpdb_query('query', [$SQL]);
-        } else {
-            $rows_deleted = 0;
-        }
-
-        // Next, make sure those items are removed from the entity map; if they could be put into it at all; and if
-        // there was no error with the delete query.
-        if (
-            $this->has_primary_key_field()
-            && $rows_deleted !== false
-            && isset($columns_and_ids_for_deleting[ $this->get_primary_key_field()->get_qualified_column() ])
-        ) {
-            $ids_for_removal = $columns_and_ids_for_deleting[ $this->get_primary_key_field()->get_qualified_column() ];
-            foreach ($ids_for_removal as $id) {
-                if (isset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ])) {
-                    unset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ]);
-                }
-            }
-
-            // delete any extra meta attached to the deleted entities but ONLY if this model is not an instance of
-            // `EEM_Extra_Meta`.  In other words we want to prevent recursion on EEM_Extra_Meta::delete_permanently calls
-            // unnecessarily.  It's very unlikely that users will have assigned Extra Meta to Extra Meta
-            // (although it is possible).
-            // Note this can be skipped by using the provided filter and returning false.
-            if (
-                apply_filters(
-                    'FHEE__EEM_Base__delete_permanently__dont_delete_extra_meta_for_extra_meta',
-                    ! $this instanceof EEM_Extra_Meta,
-                    $this
-                )
-            ) {
-                EEM_Extra_Meta::instance()->delete_permanently([
-                                                                   0 => [
-                                                                       'EXM_type' => $this->get_this_model_name(),
-                                                                       'OBJ_ID'   => [
-                                                                           'IN',
-                                                                           $ids_for_removal,
-                                                                       ],
-                                                                   ],
-                                                               ]);
-            }
-        }
-
-        /**
-         * Action called just after performing a real deletion query. Although at this point the
-         * items should have been deleted
-         *
-         * @param EEM_Base $model
-         * @param array    $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-         * @param int      $rows_deleted
-         */
-        do_action('AHEE__EEM_Base__delete__end', $this, $query_params, $rows_deleted, $columns_and_ids_for_deleting);
-        return $rows_deleted;// how many supposedly got deleted
-    }
-
-
-    /**
-     * Checks all the relations that throw error messages when there are blocking related objects
-     * for related model objects. If there are any related model objects on those relations,
-     * adds an EE_Error, and return true
-     *
-     * @param EE_Base_Class|int $this_model_obj_or_id
-     * @param EE_Base_Class     $ignore_this_model_obj a model object like 'EE_Event', or 'EE_Term_Taxonomy', which
-     *                                                 should be ignored when determining whether there are related
-     *                                                 model objects which block this model object's deletion. Useful
-     *                                                 if you know A is related to B and are considering deleting A,
-     *                                                 but want to see if A has any other objects blocking its deletion
-     *                                                 before removing the relation between A and B
-     * @return boolean
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function delete_is_blocked_by_related_models($this_model_obj_or_id, $ignore_this_model_obj = null)
-    {
-        // first, if $ignore_this_model_obj was supplied, get its model
-        if ($ignore_this_model_obj && $ignore_this_model_obj instanceof EE_Base_Class) {
-            $ignored_model = $ignore_this_model_obj->get_model();
-        } else {
-            $ignored_model = null;
-        }
-        // now check all the relations of $this_model_obj_or_id and see if there
-        // are any related model objects blocking it?
-        $is_blocked = false;
-        foreach ($this->_model_relations as $relation_name => $relation_obj) {
-            if ($relation_obj->block_delete_if_related_models_exist()) {
-                // if $ignore_this_model_obj was supplied, then for the query
-                // on that model needs to be told to ignore $ignore_this_model_obj
-                if ($ignored_model && $relation_name === $ignored_model->get_this_model_name()) {
-                    $related_model_objects = $relation_obj->get_all_related($this_model_obj_or_id, [
-                        [
-                            $ignored_model->get_primary_key_field()->get_name() => [
-                                '!=',
-                                $ignore_this_model_obj->ID(),
-                            ],
-                        ],
-                    ]);
-                } else {
-                    $related_model_objects = $relation_obj->get_all_related($this_model_obj_or_id);
-                }
-                if ($related_model_objects) {
-                    EE_Error::add_error($relation_obj->get_deletion_error_message(), __FILE__, __FUNCTION__, __LINE__);
-                    $is_blocked = true;
-                }
-            }
-        }
-        return $is_blocked;
-    }
-
-
-    /**
-     * Builds the columns and values for items to delete from the incoming $row_results_for_deleting array.
-     *
-     * @param array $row_results_for_deleting
-     * @param bool  $allow_blocking
-     * @return array   The shape of this array depends on whether the model `has_primary_key_field` or not.  If the
-     *                              model DOES have a primary_key_field, then the array will be a simple single
-     *                              dimension array where the key is the fully qualified primary key column and the
-     *                              value is an array of ids that will be deleted. Example: array('Event.EVT_ID' =>
-     *                              array( 1,2,3)) If the model DOES NOT have a primary_key_field, then the array will
-     *                              be a two dimensional array where each element is a group of columns and values that
-     *                              get deleted. Example: array(
-     *                              0 => array(
-     *                              'Term_Relationship.object_id' => 1
-     *                              'Term_Relationship.term_taxonomy_id' => 5
-     *                              ),
-     *                              1 => array(
-     *                              'Term_Relationship.object_id' => 1
-     *                              'Term_Relationship.term_taxonomy_id' => 6
-     *                              )
-     *                              )
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _get_ids_for_delete(array $row_results_for_deleting, $allow_blocking = true)
-    {
-        $ids_to_delete_indexed_by_column = [];
-        if ($this->has_primary_key_field()) {
-            $primary_table                   = $this->_get_main_table();
-            $primary_table_pk_field          =
-                $this->get_field_by_column($primary_table->get_fully_qualified_pk_column());
-            $other_tables                    = $this->_get_other_tables();
-            $ids_to_delete_indexed_by_column = $query = [];
-            foreach ($row_results_for_deleting as $item_to_delete) {
-                // before we mark this item for deletion,
-                // make sure there's no related entities blocking its deletion (if we're checking)
-                if (
-                    $allow_blocking
-                    && $this->delete_is_blocked_by_related_models(
-                        $item_to_delete[ $primary_table->get_fully_qualified_pk_column() ]
-                    )
-                ) {
-                    continue;
-                }
-                // primary table deletes
-                if (isset($item_to_delete[ $primary_table->get_fully_qualified_pk_column() ])) {
-                    $ids_to_delete_indexed_by_column[ $primary_table->get_fully_qualified_pk_column() ][] =
-                        $item_to_delete[ $primary_table->get_fully_qualified_pk_column() ];
-                }
-            }
-        } elseif (count($this->get_combined_primary_key_fields()) > 1) {
-            $fields = $this->get_combined_primary_key_fields();
-            foreach ($row_results_for_deleting as $item_to_delete) {
-                $ids_to_delete_indexed_by_column_for_row = [];
-                foreach ($fields as $cpk_field) {
-                    if ($cpk_field instanceof EE_Model_Field_Base) {
-                        $ids_to_delete_indexed_by_column_for_row[ $cpk_field->get_qualified_column() ] =
-                            $item_to_delete[ $cpk_field->get_qualified_column() ];
-                    }
-                }
-                $ids_to_delete_indexed_by_column[] = $ids_to_delete_indexed_by_column_for_row;
-            }
-        } else {
-            // so there's no primary key and no combined key...
-            // sorry, can't help you
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "Cannot delete objects of type %s because there is no primary key NOR combined key",
-                        "event_espresso"
-                    ),
-                    get_class($this)
-                )
-            );
-        }
-        return $ids_to_delete_indexed_by_column;
-    }
-
-
-    /**
-     * This receives an array of columns and values set to be deleted (as prepared by _get_ids_for_delete) and prepares
-     * the corresponding query_part for the query performing the delete.
-     *
-     * @param array $ids_to_delete_indexed_by_column @see _get_ids_for_delete for how this array might be shaped.
-     * @return string
-     * @throws EE_Error
-     */
-    protected function _build_query_part_for_deleting_from_columns_and_values(array $ids_to_delete_indexed_by_column)
-    {
-        $query_part = '';
-        if (empty($ids_to_delete_indexed_by_column)) {
-            return $query_part;
-        } elseif ($this->has_primary_key_field()) {
-            $query = [];
-            foreach ($ids_to_delete_indexed_by_column as $column => $ids) {
-                $query[] = $column . ' IN' . $this->_construct_in_value($ids, $this->_primary_key_field);
-            }
-            $query_part = ! empty($query) ? implode(' AND ', $query) : $query_part;
-        } elseif (count($this->get_combined_primary_key_fields()) > 1) {
-            $ways_to_identify_a_row = [];
-            foreach ($ids_to_delete_indexed_by_column as $ids_to_delete_indexed_by_column_for_each_row) {
-                $values_for_each_combined_primary_key_for_a_row = [];
-                foreach ($ids_to_delete_indexed_by_column_for_each_row as $column => $id) {
-                    $values_for_each_combined_primary_key_for_a_row[] = $column . '=' . $id;
-                }
-                $ways_to_identify_a_row[] = '('
-                                            . implode(' AND ', $values_for_each_combined_primary_key_for_a_row)
-                                            . ')';
-            }
-            $query_part = implode(' OR ', $ways_to_identify_a_row);
-        }
-        return $query_part;
-    }
-
-
-    /**
-     * Gets the model field by the fully qualified name
-     *
-     * @param string $qualified_column_name eg 'Event_CPT.post_name' or $field_obj->get_qualified_column()
-     * @return EE_Model_Field_Base
-     * @throws EE_Error
-     * @throws EE_Error
-     */
-    public function get_field_by_column($qualified_column_name)
-    {
-        foreach ($this->field_settings(true) as $field_name => $field_obj) {
-            if ($field_obj->get_qualified_column() === $qualified_column_name) {
-                return $field_obj;
-            }
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__('Could not find a field on the model "%1$s" for qualified column "%2$s"', 'event_espresso'),
-                $this->get_this_model_name(),
-                $qualified_column_name
-            )
-        );
-    }
-
-
-    /**
-     * Count all the rows that match criteria the model query params.
-     * If $field_to_count isn't provided, the model's primary key is used. Otherwise, we count by field_to_count's
-     * column
-     *
-     * @param array  $query_params   @see
-     *                               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_count field on model to count by (not column name)
-     * @param bool   $distinct       if we want to only count the distinct values for the column then you can trigger
-     *                               that by the setting $distinct to TRUE;
-     * @return int
-     * @throws EE_Error
-     */
-    public function count($query_params = [], $field_to_count = null, $distinct = false)
-    {
-        $model_query_info = $this->_create_model_query_info_carrier($query_params);
-        if ($field_to_count) {
-            $field_obj       = $this->field_settings_for($field_to_count);
-            $column_to_count = $field_obj->get_qualified_column();
-        } elseif ($this->has_primary_key_field()) {
-            $pk_field_obj    = $this->get_primary_key_field();
-            $column_to_count = $pk_field_obj->get_qualified_column();
-        } else {
-            // there's no primary key
-            // if we're counting distinct items, and there's no primary key,
-            // we need to list out the columns for distinction;
-            // otherwise we can just use star
-            if ($distinct) {
-                $columns_to_use = [];
-                foreach ($this->get_combined_primary_key_fields() as $field_obj) {
-                    $columns_to_use[] = $field_obj->get_qualified_column();
-                }
-                $column_to_count = implode(',', $columns_to_use);
-            } else {
-                $column_to_count = '*';
-            }
-        }
-        $column_to_count = $distinct ? "DISTINCT " . $column_to_count : $column_to_count;
-        $SQL             =
-            "SELECT COUNT(" . $column_to_count . ")" . $this->_construct_2nd_half_of_select_query($model_query_info);
-        return (int) $this->_do_wpdb_query('get_var', [$SQL]);
-    }
-
-
-    /**
-     * Sums up the value of the $field_to_sum (defaults to the primary key, which isn't terribly useful)
-     *
-     * @param array  $query_params @see
-     *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_sum name of field (array key in $_fields array)
-     * @return float
-     * @throws EE_Error
-     */
-    public function sum($query_params, $field_to_sum = null)
-    {
-        $model_query_info = $this->_create_model_query_info_carrier($query_params);
-        if ($field_to_sum) {
-            $field_obj = $this->field_settings_for($field_to_sum);
-        } else {
-            $field_obj = $this->get_primary_key_field();
-        }
-        $column_to_count = $field_obj->get_qualified_column();
-        $SQL             =
-            "SELECT SUM(" . $column_to_count . ")" . $this->_construct_2nd_half_of_select_query($model_query_info);
-        $return_value    = $this->_do_wpdb_query('get_var', [$SQL]);
-        $data_type       = $field_obj->get_wpdb_data_type();
-        if ($data_type === '%d' || $data_type === '%s') {
-            return (float) $return_value;
-        }
-        // must be %f
-        return (float) $return_value;
-    }
-
-
-    /**
-     * Just calls the specified method on $wpdb with the given arguments
-     * Consolidates a little extra error handling code
-     *
-     * @param string $wpdb_method
-     * @param array  $arguments_to_provide
-     * @return mixed
-     * @throws EE_Error
-     * @global wpdb  $wpdb
-     */
-    protected function _do_wpdb_query($wpdb_method, $arguments_to_provide)
-    {
-        // if we're in maintenance mode level 2, DON'T run any queries
-        // because level 2 indicates the database needs updating and
-        // is probably out of sync with the code
-        if (! EE_Maintenance_Mode::instance()->models_can_query()) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "Event Espresso Level 2 Maintenance mode is active. That means EE can not run ANY database queries until the necessary migration scripts have run which will take EE out of maintenance mode level 2. Please inform support of this error.",
-                        "event_espresso"
-                    )
-                )
-            );
-        }
-        /** @type WPDB $wpdb */
-        global $wpdb;
-        if (! method_exists($wpdb, $wpdb_method)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'There is no method named "%s" on Wordpress\' $wpdb object',
-                        'event_espresso'
-                    ),
-                    $wpdb_method
-                )
-            );
-        }
-        if (WP_DEBUG) {
-            $old_show_errors_value = $wpdb->show_errors;
-            $wpdb->show_errors(false);
-        }
-        $result = $this->_process_wpdb_query($wpdb_method, $arguments_to_provide);
-        $this->show_db_query_if_previously_requested($wpdb->last_query);
-        if (WP_DEBUG) {
-            $wpdb->show_errors($old_show_errors_value);
-            if (! empty($wpdb->last_error)) {
-                throw new EE_Error(sprintf(esc_html__('WPDB Error: "%s"', 'event_espresso'), $wpdb->last_error));
-            }
-            if ($result === false) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'WPDB Error occurred, but no error message was logged by wpdb! The wpdb method called was "%1$s" and the arguments were "%2$s"',
-                            'event_espresso'
-                        ),
-                        $wpdb_method,
-                        var_export($arguments_to_provide, true)
-                    )
-                );
-            }
-        } elseif ($result === false) {
-            EE_Error::add_error(
-                sprintf(
-                    esc_html__(
-                        'A database error has occurred. Turn on WP_DEBUG for more information.||A database error occurred doing wpdb method "%1$s", with arguments "%2$s". The error was "%3$s"',
-                        'event_espresso'
-                    ),
-                    $wpdb_method,
-                    var_export($arguments_to_provide, true),
-                    $wpdb->last_error
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        }
-        return $result;
-    }
-
-
-    /**
-     * Attempts to run the indicated WPDB method with the provided arguments,
-     * and if there's an error tries to verify the DB is correct. Uses
-     * the static property EEM_Base::$_db_verification_level to determine whether
-     * we should try to fix the EE core db, the addons, or just give up
-     *
-     * @param string $wpdb_method
-     * @param array  $arguments_to_provide
-     * @return mixed
-     */
-    private function _process_wpdb_query($wpdb_method, $arguments_to_provide)
-    {
-        /** @type WPDB $wpdb */
-        global $wpdb;
-        $wpdb->last_error = null;
-        $result           = call_user_func_array([$wpdb, $wpdb_method], $arguments_to_provide);
-        // was there an error running the query? but we don't care on new activations
-        // (we're going to setup the DB anyway on new activations)
-        if (
-            ($result === false || ! empty($wpdb->last_error))
-            && EE_System::instance()->detect_req_type() !== EE_System::req_type_new_activation
-        ) {
-            switch (EEM_Base::$_db_verification_level) {
-                case EEM_Base::db_verified_none:
-                    // let's double-check core's DB
-                    $error_message = $this->_verify_core_db($wpdb_method, $arguments_to_provide);
-                    break;
-                case EEM_Base::db_verified_core:
-                    // STILL NO LOVE?? verify all the addons too. Maybe they need to be fixed
-                    $error_message = $this->_verify_addons_db($wpdb_method, $arguments_to_provide);
-                    break;
-                case EEM_Base::db_verified_addons:
-                    // ummmm... you in trouble
-                    return $result;
-            }
-            if (! empty($error_message)) {
-                EE_Log::instance()->log(__FILE__, __FUNCTION__, $error_message, 'error');
-                trigger_error($error_message);
-            }
-            return $this->_process_wpdb_query($wpdb_method, $arguments_to_provide);
-        }
-        return $result;
-    }
-
-
-    /**
-     * Verifies the EE core database is up-to-date and records that we've done it on
-     * EEM_Base::$_db_verification_level
-     *
-     * @param string $wpdb_method
-     * @param array  $arguments_to_provide
-     * @return string
-     */
-    private function _verify_core_db($wpdb_method, $arguments_to_provide)
-    {
-        /** @type WPDB $wpdb */
-        global $wpdb;
-        // ok remember that we've already attempted fixing the core db, in case the problem persists
-        EEM_Base::$_db_verification_level = EEM_Base::db_verified_core;
-        $error_message                    = sprintf(
-            esc_html__(
-                'WPDB Error "%1$s" while running wpdb method "%2$s" with arguments %3$s. Automatically attempting to fix EE Core DB',
-                'event_espresso'
-            ),
-            $wpdb->last_error,
-            $wpdb_method,
-            wp_json_encode($arguments_to_provide)
-        );
-        EE_System::instance()->initialize_db_if_no_migrations_required(false, true);
-        return $error_message;
-    }
-
-
-    /**
-     * Verifies the EE addons' database is up-to-date and records that we've done it on
-     * EEM_Base::$_db_verification_level
-     *
-     * @param $wpdb_method
-     * @param $arguments_to_provide
-     * @return string
-     */
-    private function _verify_addons_db($wpdb_method, $arguments_to_provide)
-    {
-        /** @type WPDB $wpdb */
-        global $wpdb;
-        // ok remember that we've already attempted fixing the addons dbs, in case the problem persists
-        EEM_Base::$_db_verification_level = EEM_Base::db_verified_addons;
-        $error_message                    = sprintf(
-            esc_html__(
-                'WPDB AGAIN: Error "%1$s" while running the same method and arguments as before. Automatically attempting to fix EE Addons DB',
-                'event_espresso'
-            ),
-            $wpdb->last_error,
-            $wpdb_method,
-            wp_json_encode($arguments_to_provide)
-        );
-        EE_System::instance()->initialize_addons();
-        return $error_message;
-    }
-
-
-    /**
-     * In order to avoid repeating this code for the get_all, sum, and count functions, put the code parts
-     * that are identical in here. Returns a string of SQL of everything in a SELECT query except the beginning
-     * SELECT clause, eg " FROM wp_posts AS Event INNER JOIN ... WHERE ... ORDER BY ... LIMIT ... GROUP BY ... HAVING
-     * ..."
-     *
-     * @param EE_Model_Query_Info_Carrier $model_query_info
-     * @return string
-     */
-    private function _construct_2nd_half_of_select_query(EE_Model_Query_Info_Carrier $model_query_info)
-    {
-        return " FROM " . $model_query_info->get_full_join_sql() .
-               $model_query_info->get_where_sql() .
-               $model_query_info->get_group_by_sql() .
-               $model_query_info->get_having_sql() .
-               $model_query_info->get_order_by_sql() .
-               $model_query_info->get_limit_sql();
-    }
-
-
-    /**
-     * Set to easily debug the next X queries ran from this model.
-     *
-     * @param int $count
-     */
-    public function show_next_x_db_queries($count = 1)
-    {
-        $this->_show_next_x_db_queries = $count;
-    }
-
-
-    /**
-     * @param $sql_query
-     */
-    public function show_db_query_if_previously_requested($sql_query)
-    {
-        if ($this->_show_next_x_db_queries > 0) {
-            echo esc_html($sql_query);
-            $this->_show_next_x_db_queries--;
-        }
-    }
-
-
-    /**
-     * Adds a relationship of the correct type between $modelObject and $otherModelObject.
-     * There are the 3 cases:
-     * 'belongsTo' relationship: sets $id_or_obj's foreign_key to be $other_model_id_or_obj's primary_key. If
-     * $otherModelObject has no ID, it is first saved.
-     * 'hasMany' relationship: sets $other_model_id_or_obj's foreign_key to be $id_or_obj's primary_key. If $id_or_obj
-     * has no ID, it is first saved.
-     * 'hasAndBelongsToMany' relationships: checks that there isn't already an entry in the join table, and adds one.
-     * If one of the model Objects has not yet been saved to the database, it is saved before adding the entry in the
-     * join table
-     *
-     * @param EE_Base_Class                     /int $thisModelObject
-     * @param EE_Base_Class                     /int $id_or_obj EE_base_Class or ID of other Model Object
-     * @param string $relationName                     , key in EEM_Base::_relations
-     *                                                 an attendee to a group, you also want to specify which role they
-     *                                                 will have in that group. So you would use this parameter to
-     *                                                 specify array('role-column-name'=>'role-id')
-     * @param array  $extra_join_model_fields_n_values This allows you to enter further query params for the relation
-     *                                                 to for relation to methods that allow you to further specify
-     *                                                 extra columns to join by (such as HABTM).  Keep in mind that the
-     *                                                 only acceptable query_params is strict "col" => "value" pairs
-     *                                                 because these will be inserted in any new rows created as well.
-     * @return EE_Base_Class which was added as a relation. Object referred to by $other_model_id_or_obj
-     * @throws EE_Error
-     */
-    public function add_relationship_to(
-        $id_or_obj,
-        $other_model_id_or_obj,
-        $relationName,
-        $extra_join_model_fields_n_values = []
-    ) {
-        $relation_obj = $this->related_settings_for($relationName);
-        return $relation_obj->add_relation_to($id_or_obj, $other_model_id_or_obj, $extra_join_model_fields_n_values);
-    }
-
-
-    /**
-     * Removes a relationship of the correct type between $modelObject and $otherModelObject.
-     * There are the 3 cases:
-     * 'belongsTo' relationship: sets $modelObject's foreign_key to null, if that field is nullable.Otherwise throws an
-     * error
-     * 'hasMany' relationship: sets $otherModelObject's foreign_key to null,if that field is nullable.Otherwise throws
-     * an error
-     * 'hasAndBelongsToMany' relationships:removes any existing entry in the join table between the two models.
-     *
-     * @param EE_Base_Class /int $id_or_obj
-     * @param EE_Base_Class /int $other_model_id_or_obj EE_Base_Class or ID of other Model Object
-     * @param string $relationName key in EEM_Base::_relations
-     * @param array  $where_query  This allows you to enter further query params for the relation to for relation to
-     *                             methods that allow you to further specify extra columns to join by (such as HABTM).
-     *                             Keep in mind that the only acceptable query_params is strict "col" => "value" pairs
-     *                             because these will be inserted in any new rows created as well.
-     * @return boolean of success
-     * @throws EE_Error
-     */
-    public function remove_relationship_to($id_or_obj, $other_model_id_or_obj, $relationName, $where_query = [])
-    {
-        $relation_obj = $this->related_settings_for($relationName);
-        return $relation_obj->remove_relation_to($id_or_obj, $other_model_id_or_obj, $where_query);
-    }
-
-
-    /**
-     * @param mixed  $id_or_obj
-     * @param string $relationName
-     * @param array  $where_query_params
-     * @param EE_Base_Class[] objects to which relations were removed
-     * @return EE_Base_Class[]
-     * @throws EE_Error
-     */
-    public function remove_relations($id_or_obj, $relationName, $where_query_params = [])
-    {
-        $relation_obj = $this->related_settings_for($relationName);
-        return $relation_obj->remove_relations($id_or_obj, $where_query_params);
-    }
-
-
-    /**
-     * Gets all the related items of the specified $model_name, using $query_params.
-     * Note: by default, we remove the "default query params"
-     * because we want to get even deleted items etc.
-     *
-     * @param mixed  $id_or_obj    EE_Base_Class child or its ID
-     * @param string $model_name   like 'Event', 'Registration', etc. always singular
-     * @param array  $query_params @see
-     *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Base_Class[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_all_related($id_or_obj, $model_name, $query_params = null)
-    {
-        $model_obj         = $this->ensure_is_obj($id_or_obj);
-        $relation_settings = $this->related_settings_for($model_name);
-        return $relation_settings->get_all_related($model_obj, $query_params);
-    }
-
-
-    /**
-     * Deletes all the model objects across the relation indicated by $model_name
-     * which are related to $id_or_obj which meet the criteria set in $query_params.
-     * However, if the model objects can't be deleted because of blocking related model objects, then
-     * they aren't deleted. (Unless the thing that would have been deleted can be soft-deleted, that still happens).
-     *
-     * @param EE_Base_Class|int|string $id_or_obj
-     * @param string                   $model_name
-     * @param array                    $query_params
-     * @return int how many deleted
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function delete_related($id_or_obj, $model_name, $query_params = [])
-    {
-        $model_obj         = $this->ensure_is_obj($id_or_obj);
-        $relation_settings = $this->related_settings_for($model_name);
-        return $relation_settings->delete_all_related($model_obj, $query_params);
-    }
-
-
-    /**
-     * Hard deletes all the model objects across the relation indicated by $model_name
-     * which are related to $id_or_obj which meet the criteria set in $query_params. If
-     * the model objects can't be hard deleted because of blocking related model objects,
-     * just does a soft-delete on them instead.
-     *
-     * @param EE_Base_Class|int|string $id_or_obj
-     * @param string                   $model_name
-     * @param array                    $query_params
-     * @return int how many deleted
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function delete_related_permanently($id_or_obj, $model_name, $query_params = [])
-    {
-        $model_obj         = $this->ensure_is_obj($id_or_obj);
-        $relation_settings = $this->related_settings_for($model_name);
-        return $relation_settings->delete_related_permanently($model_obj, $query_params);
-    }
-
-
-    /**
-     * Instead of getting the related model objects, simply counts them. Ignores default_where_conditions by default,
-     * unless otherwise specified in the $query_params
-     *
-     * @param int             /EE_Base_Class $id_or_obj
-     * @param string $model_name     like 'Event', or 'Registration'
-     * @param array  $query_params   @see
-     *                               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_count name of field to count by. By default, uses primary key
-     * @param bool   $distinct       if we want to only count the distinct values for the column then you can trigger
-     *                               that by the setting $distinct to TRUE;
-     * @return int
-     * @throws EE_Error
-     */
-    public function count_related(
-        $id_or_obj,
-        $model_name,
-        $query_params = [],
-        $field_to_count = null,
-        $distinct = false
-    ) {
-        $related_model = $this->get_related_model_obj($model_name);
-        // we're just going to use the query params on the related model's normal get_all query,
-        // except add a condition to say to match the current mod
-        if (! isset($query_params['default_where_conditions'])) {
-            $query_params['default_where_conditions'] = EEM_Base::default_where_conditions_none;
-        }
-        $this_model_name                                                 = $this->get_this_model_name();
-        $this_pk_field_name                                              = $this->get_primary_key_field()->get_name();
-        $query_params[0][ $this_model_name . "." . $this_pk_field_name ] = $id_or_obj;
-        return $related_model->count($query_params, $field_to_count, $distinct);
-    }
-
-
-    /**
-     * Instead of getting the related model objects, simply sums up the values of the specified field.
-     * Note: ignores default_where_conditions by default, unless otherwise specified in the $query_params
-     *
-     * @param int           /EE_Base_Class $id_or_obj
-     * @param string $model_name   like 'Event', or 'Registration'
-     * @param array  $query_params @see
-     *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_sum name of field to count by. By default, uses primary key
-     * @return float
-     * @throws EE_Error
-     */
-    public function sum_related($id_or_obj, $model_name, $query_params, $field_to_sum = null)
-    {
-        $related_model = $this->get_related_model_obj($model_name);
-        if (! is_array($query_params)) {
-            EE_Error::doing_it_wrong(
-                'EEM_Base::sum_related',
-                sprintf(
-                    esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
-                    gettype($query_params)
-                ),
-                '4.6.0'
-            );
-            $query_params = [];
-        }
-        // we're just going to use the query params on the related model's normal get_all query,
-        // except add a condition to say to match the current mod
-        if (! isset($query_params['default_where_conditions'])) {
-            $query_params['default_where_conditions'] = EEM_Base::default_where_conditions_none;
-        }
-        $this_model_name                                                 = $this->get_this_model_name();
-        $this_pk_field_name                                              = $this->get_primary_key_field()->get_name();
-        $query_params[0][ $this_model_name . "." . $this_pk_field_name ] = $id_or_obj;
-        return $related_model->sum($query_params, $field_to_sum);
-    }
-
-
-    /**
-     * Uses $this->_relatedModels info to find the first related model object of relation $relationName to the given
-     * $modelObject
-     *
-     * @param int | EE_Base_Class $id_or_obj        EE_Base_Class child or its ID
-     * @param string              $other_model_name , key in $this->_relatedModels, eg 'Registration', or 'Events'
-     * @param array               $query_params     @see
-     *                                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Base_Class
-     * @throws EE_Error
-     */
-    public function get_first_related(EE_Base_Class $id_or_obj, $other_model_name, $query_params)
-    {
-        $query_params['limit'] = 1;
-        $results               = $this->get_all_related($id_or_obj, $other_model_name, $query_params);
-        if ($results) {
-            return array_shift($results);
-        }
-        return null;
-    }
-
-
-    /**
-     * Gets the model's name as it's expected in queries. For example, if this is EEM_Event model, that would be Event
-     *
-     * @return string
-     */
-    public function get_this_model_name()
-    {
-        return str_replace("EEM_", "", get_class($this));
-    }
-
-
-    /**
-     * Gets the model field on this model which is of type EE_Any_Foreign_Model_Name_Field
-     *
-     * @return EE_Any_Foreign_Model_Name_Field
-     * @throws EE_Error
-     */
-    public function get_field_containing_related_model_name()
-    {
-        foreach ($this->field_settings(true) as $field) {
-            if ($field instanceof EE_Any_Foreign_Model_Name_Field) {
-                $field_with_model_name = $field;
-            }
-        }
-        if (! isset($field_with_model_name) || ! $field_with_model_name) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__("There is no EE_Any_Foreign_Model_Name field on model %s", "event_espresso"),
-                    $this->get_this_model_name()
-                )
-            );
-        }
-        return $field_with_model_name;
-    }
-
-
-    /**
-     * Inserts a new entry into the database, for each table.
-     * Note: does not add the item to the entity map because that is done by EE_Base_Class::save() right after this.
-     * If client code uses EEM_Base::insert() directly, then although the item isn't in the entity map,
-     * we also know there is no model object with the newly inserted item's ID at the moment (because
-     * if there were, then they would already be in the DB and this would fail); and in the future if someone
-     * creates a model object with this ID (or grabs it from the DB) then it will be added to the
-     * entity map at that time anyways. SO, no need for EEM_Base::insert ot add to the entity map
-     *
-     * @param array $field_n_values keys are field names, values are their values (in the client code's domain if
-     *                              $values_already_prepared_by_model_object is false, in the model object's domain if
-     *                              $values_already_prepared_by_model_object is true. See comment about this at the top
-     *                              of EEM_Base)
-     * @return int|string new primary key on main table that got inserted
-     * @throws EE_Error
-     */
-    public function insert($field_n_values)
-    {
-        /**
-         * Filters the fields and their values before inserting an item using the models
-         *
-         * @param array    $fields_n_values keys are the fields and values are their new values
-         * @param EEM_Base $model           the model used
-         */
-        $field_n_values = (array) apply_filters('FHEE__EEM_Base__insert__fields_n_values', $field_n_values, $this);
-        if ($this->_satisfies_unique_indexes($field_n_values)) {
-            $main_table = $this->_get_main_table();
-            $new_id     = $this->_insert_into_specific_table($main_table, $field_n_values, false);
-            if ($new_id !== false) {
-                foreach ($this->_get_other_tables() as $other_table) {
-                    $this->_insert_into_specific_table($other_table, $field_n_values, $new_id);
-                }
-            }
-            /**
-             * Done just after attempting to insert a new model object
-             *
-             * @param EEM_Base $model           used
-             * @param array    $fields_n_values fields and their values
-             * @param int|string the              ID of the newly-inserted model object
-             */
-            do_action('AHEE__EEM_Base__insert__end', $this, $field_n_values, $new_id);
-            return $new_id;
-        }
-        return false;
-    }
-
-
-    /**
-     * Checks that the result would satisfy the unique indexes on this model
-     *
-     * @param array  $field_n_values
-     * @param string $action
-     * @return boolean
-     * @throws EE_Error
-     */
-    protected function _satisfies_unique_indexes($field_n_values, $action = 'insert')
-    {
-        foreach ($this->unique_indexes() as $index_name => $index) {
-            $uniqueness_where_params = array_intersect_key($field_n_values, $index->fields());
-            if ($this->exists([$uniqueness_where_params])) {
-                EE_Error::add_error(
-                    sprintf(
-                        esc_html__(
-                            "Could not %s %s. %s uniqueness index failed. Fields %s must form a unique set, but an entry already exists with values %s.",
-                            "event_espresso"
-                        ),
-                        $action,
-                        $this->_get_class_name(),
-                        $index_name,
-                        implode(",", $index->field_names()),
-                        http_build_query($uniqueness_where_params)
-                    ),
-                    __FILE__,
-                    __FUNCTION__,
-                    __LINE__
-                );
-                return false;
-            }
-        }
-        return true;
-    }
-
-
-    /**
-     * Checks the database for an item that conflicts (ie, if this item were
-     * saved to the DB would break some uniqueness requirement, like a primary key
-     * or an index primary key set) with the item specified. $id_obj_or_fields_array
-     * can be either an EE_Base_Class or an array of fields n values
-     *
-     * @param EE_Base_Class|array $obj_or_fields_array
-     * @param boolean             $include_primary_key whether to use the model object's primary key
-     *                                                 when looking for conflicts
-     *                                                 (ie, if false, we ignore the model object's primary key
-     *                                                 when finding "conflicts". If true, it's also considered).
-     *                                                 Only works for INT primary key,
-     *                                                 STRING primary keys cannot be ignored
-     * @return EE_Base_Class|array
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_one_conflicting($obj_or_fields_array, $include_primary_key = true)
-    {
-        if ($obj_or_fields_array instanceof EE_Base_Class) {
-            $fields_n_values = $obj_or_fields_array->model_field_array();
-        } elseif (is_array($obj_or_fields_array)) {
-            $fields_n_values = $obj_or_fields_array;
-        } else {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "%s get_all_conflicting should be called with a model object or an array of field names and values, you provided %d",
-                        "event_espresso"
-                    ),
-                    get_class($this),
-                    $obj_or_fields_array
-                )
-            );
-        }
-        $query_params = [];
-        if (
-            $this->has_primary_key_field()
-            && ($include_primary_key
-                || $this->get_primary_key_field()
-                   instanceof
-                   EE_Primary_Key_String_Field)
-            && isset($fields_n_values[ $this->primary_key_name() ])
-        ) {
-            $query_params[0]['OR'][ $this->primary_key_name() ] = $fields_n_values[ $this->primary_key_name() ];
-        }
-        foreach ($this->unique_indexes() as $unique_index_name => $unique_index) {
-            $uniqueness_where_params                              =
-                array_intersect_key($fields_n_values, $unique_index->fields());
-            $query_params[0]['OR'][ 'AND*' . $unique_index_name ] = $uniqueness_where_params;
-        }
-        // if there is nothing to base this search on, then we shouldn't find anything
-        if (empty($query_params)) {
-            return [];
-        }
-        return $this->get_one($query_params);
-    }
-
-
-    /**
-     * Like count, but is optimized and returns a boolean instead of an int
-     *
-     * @param array $query_params
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function exists($query_params)
-    {
-        $query_params['limit'] = 1;
-        return $this->count($query_params) > 0;
-    }
-
-
-    /**
-     * Wrapper for exists, except ignores default query parameters so we're only considering ID
-     *
-     * @param int|string $id
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function exists_by_ID($id)
-    {
-        return $this->exists(
-            [
-                'default_where_conditions' => EEM_Base::default_where_conditions_none,
-                [
-                    $this->primary_key_name() => $id,
-                ],
-            ]
-        );
-    }
-
-
-    /**
-     * Inserts a new row in $table, using the $cols_n_values which apply to that table.
-     * If a $new_id is supplied and if $table is an EE_Other_Table, we assume
-     * we need to add a foreign key column to point to $new_id (which should be the primary key's value
-     * on the main table)
-     * This is protected rather than private because private is not accessible to any child methods and there MAY be
-     * cases where we want to call it directly rather than via insert().
-     *
-     * @access   protected
-     * @param EE_Table_Base $table
-     * @param array         $fields_n_values each key should be in field's keys, and value should be an int, string or
-     *                                       float
-     * @param int           $new_id          for now we assume only int keys
-     * @return int ID of new row inserted, or FALSE on failure
-     * @throws EE_Error
-     * @global WPDB         $wpdb            only used to get the $wpdb->insert_id after performing an insert
-     */
-    protected function _insert_into_specific_table(EE_Table_Base $table, $fields_n_values, $new_id = 0)
-    {
-        global $wpdb;
-        $insertion_col_n_values = [];
-        $format_for_insertion   = [];
-        $fields_on_table        = $this->_get_fields_for_table($table->get_table_alias());
-        foreach ($fields_on_table as $field_name => $field_obj) {
-            // check if its an auto-incrementing column, in which case we should just leave it to do its autoincrement thing
-            if ($field_obj->is_auto_increment()) {
-                continue;
-            }
-            $prepared_value = $this->_prepare_value_or_use_default($field_obj, $fields_n_values);
-            // if the value we want to assign it to is NULL, just don't mention it for the insertion
-            if ($prepared_value !== null) {
-                $insertion_col_n_values[ $field_obj->get_table_column() ] = $prepared_value;
-                $format_for_insertion[]                                   = $field_obj->get_wpdb_data_type();
-            }
-        }
-        if ($table instanceof EE_Secondary_Table && $new_id) {
-            // its not the main table, so we should have already saved the main table's PK which we just inserted
-            // so add the fk to the main table as a column
-            $insertion_col_n_values[ $table->get_fk_on_table() ] = $new_id;
-            $format_for_insertion[]                              =
-                '%d';// yes right now we're only allowing these foreign keys to be INTs
-        }
-
-        // insert the new entry
-        $result = $this->_do_wpdb_query(
-            'insert',
-            [$table->get_table_name(), $insertion_col_n_values, $format_for_insertion]
-        );
-        if ($result === false) {
-            return false;
-        }
-        // ok, now what do we return for the ID of the newly-inserted thing?
-        if ($this->has_primary_key_field()) {
-            if ($this->get_primary_key_field()->is_auto_increment()) {
-                return $wpdb->insert_id;
-            }
-            // it's not an auto-increment primary key, so
-            // it must have been supplied
-            return $fields_n_values[ $this->get_primary_key_field()->get_name() ];
-        }
-        // we can't return a  primary key because there is none. instead return
-        // a unique string indicating this model
-        return $this->get_index_primary_key_string($fields_n_values);
-    }
-
-
-    /**
-     * Prepare the $field_obj 's value in $fields_n_values for use in the database.
-     * If the field doesn't allow NULL, try to use its default. (If it doesn't allow NULL,
-     * and there is no default, we pass it along. WPDB will take care of it)
-     *
-     * @param EE_Model_Field_Base $field_obj
-     * @param array               $fields_n_values
-     * @return mixed string|int|float depending on what the table column will be expecting
-     * @throws EE_Error
-     */
-    protected function _prepare_value_or_use_default($field_obj, $fields_n_values)
-    {
-        $field_name = $field_obj->get_name();
-        // if this field doesn't allow nullable, don't allow it
-        if (! $field_obj->is_nullable() && ! isset($fields_n_values[ $field_name ])) {
-            $fields_n_values[ $field_name ] = $field_obj->get_default_value();
-        }
-        $unprepared_value = $fields_n_values[ $field_name ] ?? null;
-        return $this->_prepare_value_for_use_in_db($unprepared_value, $field_obj);
-    }
-
-
-    /**
-     * Consolidates code for preparing  a value supplied to the model for use int eh db. Calls the field's
-     * prepare_for_use_in_db method on the value, and depending on $value_already_prepare_by_model_obj, may also call
-     * the field's prepare_for_set() method.
-     *
-     * @param mixed               $value value in the client code domain if $value_already_prepared_by_model_object is
-     *                                   false, otherwise a value in the model object's domain (see lengthy comment at
-     *                                   top of file)
-     * @param EE_Model_Field_Base $field field which will be doing the preparing of the value. If null, we assume
-     *                                   $value is a custom selection
-     * @return mixed a value ready for use in the database for insertions, updating, or in a where clause
-     */
-    private function _prepare_value_for_use_in_db($value, $field)
-    {
-        if ($field instanceof EE_Model_Field_Base) {
-            // phpcs:disable PSR2.ControlStructures.SwitchDeclaration.TerminatingComment
-            switch ($this->_values_already_prepared_by_model_object) {
-                /** @noinspection PhpMissingBreakStatementInspection */
-                case self::not_prepared_by_model_object:
-                    $value = $field->prepare_for_set($value);
-                // purposefully left out "return"
-                // no break
-                case self::prepared_by_model_object:
-                    /** @noinspection SuspiciousAssignmentsInspection */
-                    $value = $field->prepare_for_use_in_db($value);
-                // no break
-                case self::prepared_for_use_in_db:
-                    // leave the value alone
-            }
-            // phpcs:enable
-        }
-        return $value;
-    }
-
-
-    /**
-     * Returns the main table on this model
-     *
-     * @return EE_Primary_Table
-     * @throws EE_Error
-     */
-    protected function _get_main_table()
-    {
-        foreach ($this->_tables as $table) {
-            if ($table instanceof EE_Primary_Table) {
-                return $table;
-            }
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    'There are no main tables on %s. They should be added to _tables array in the constructor',
-                    'event_espresso'
-                ),
-                get_class($this)
-            )
-        );
-    }
-
-
-    /**
-     * table
-     * returns EE_Primary_Table table name
-     *
-     * @return string
-     * @throws EE_Error
-     */
-    public function table()
-    {
-        return $this->_get_main_table()->get_table_name();
-    }
-
-
-    /**
-     * table
-     * returns first EE_Secondary_Table table name
-     *
-     * @return string
-     */
-    public function second_table()
-    {
-        // grab second table from tables array
-        $second_table = end($this->_tables);
-        return $second_table instanceof EE_Secondary_Table ? $second_table->get_table_name() : null;
-    }
-
-
-    /**
-     * get_table_obj_by_alias
-     * returns table name given it's alias
-     *
-     * @param string $table_alias
-     * @return EE_Primary_Table | EE_Secondary_Table
-     */
-    public function get_table_obj_by_alias($table_alias = '')
-    {
-        return isset($this->_tables[ $table_alias ]) ? $this->_tables[ $table_alias ] : null;
-    }
-
-
-    /**
-     * Gets all the tables of type EE_Other_Table from EEM_CPT_Basel_Model::_tables
-     *
-     * @return EE_Secondary_Table[]
-     */
-    protected function _get_other_tables()
-    {
-        $other_tables = [];
-        foreach ($this->_tables as $table_alias => $table) {
-            if ($table instanceof EE_Secondary_Table) {
-                $other_tables[ $table_alias ] = $table;
-            }
-        }
-        return $other_tables;
-    }
-
-
-    /**
-     * Finds all the fields that correspond to the given table
-     *
-     * @param string $table_alias , array key in EEM_Base::_tables
-     * @return EE_Model_Field_Base[]
-     */
-    public function _get_fields_for_table($table_alias)
-    {
-        return $this->_fields[ $table_alias ];
-    }
-
-
-    /**
-     * Recurses through all the where parameters, and finds all the related models we'll need
-     * to complete this query. Eg, given where parameters like array('EVT_ID'=>3) from within Event model, we won't
-     * need any related models. But if the array were array('Registrations.REG_ID'=>3), we'd need the related
-     * Registration model. If it were array('Registrations.Transactions.Payments.PAY_ID'=>3), then we'd need the
-     * related Registration, Transaction, and Payment models.
-     *
-     * @param array $query_params @see
-     *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Model_Query_Info_Carrier
-     * @throws EE_Error
-     */
-    public function _extract_related_models_from_query($query_params)
-    {
-        $query_info_carrier = new EE_Model_Query_Info_Carrier();
-        if (array_key_exists(0, $query_params)) {
-            $this->_extract_related_models_from_sub_params_array_keys($query_params[0], $query_info_carrier, 0);
-        }
-        if (array_key_exists('group_by', $query_params)) {
-            if (is_array($query_params['group_by'])) {
-                $this->_extract_related_models_from_sub_params_array_values(
-                    $query_params['group_by'],
-                    $query_info_carrier,
-                    'group_by'
-                );
-            } elseif (! empty($query_params['group_by'])) {
-                $this->_extract_related_model_info_from_query_param(
-                    $query_params['group_by'],
-                    $query_info_carrier,
-                    'group_by'
-                );
-            }
-        }
-        if (array_key_exists('having', $query_params)) {
-            $this->_extract_related_models_from_sub_params_array_keys(
-                $query_params[0],
-                $query_info_carrier,
-                'having'
-            );
-        }
-        if (array_key_exists('order_by', $query_params)) {
-            if (is_array($query_params['order_by'])) {
-                $this->_extract_related_models_from_sub_params_array_keys(
-                    $query_params['order_by'],
-                    $query_info_carrier,
-                    'order_by'
-                );
-            } elseif (! empty($query_params['order_by'])) {
-                $this->_extract_related_model_info_from_query_param(
-                    $query_params['order_by'],
-                    $query_info_carrier,
-                    'order_by'
-                );
-            }
-        }
-        if (array_key_exists('force_join', $query_params)) {
-            $this->_extract_related_models_from_sub_params_array_values(
-                $query_params['force_join'],
-                $query_info_carrier,
-                'force_join'
-            );
-        }
-        $this->extractRelatedModelsFromCustomSelects($query_info_carrier);
-        return $query_info_carrier;
-    }
-
-
-    /**
-     * For extracting related models from WHERE (0), HAVING (having), ORDER BY (order_by) or forced joins (force_join)
-     *
-     * @param array                       $sub_query_params @see
-     *                                                      https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#-0-where-conditions
-     * @param EE_Model_Query_Info_Carrier $model_query_info_carrier
-     * @param string                      $query_param_type one of $this->_allowed_query_params
-     * @return EE_Model_Query_Info_Carrier
-     * @throws EE_Error
-     */
-    private function _extract_related_models_from_sub_params_array_keys(
-        $sub_query_params,
-        EE_Model_Query_Info_Carrier $model_query_info_carrier,
-        $query_param_type
-    ) {
-        if (! empty($sub_query_params)) {
-            $sub_query_params = (array) $sub_query_params;
-            foreach ($sub_query_params as $param => $possibly_array_of_params) {
-                // $param could be simply 'EVT_ID', or it could be 'Registrations.REG_ID', or even 'Registrations.Transactions.Payments.PAY_amount'
-                $this->_extract_related_model_info_from_query_param(
-                    $param,
-                    $model_query_info_carrier,
-                    $query_param_type
-                );
-                // if $possibly_array_of_params is an array, try recursing into it, searching for keys which
-                // indicate needed joins. Eg, array('NOT'=>array('Registration.TXN_ID'=>23)). In this case, we tried
-                // extracting models out of the 'NOT', which obviously wasn't successful, and then we recurse into the value
-                // of array('Registration.TXN_ID'=>23)
-                $query_param_sans_stars =
-                    $this->_remove_stars_and_anything_after_from_condition_query_param_key($param);
-                if (in_array($query_param_sans_stars, $this->_logic_query_param_keys, true)) {
-                    if (! is_array($possibly_array_of_params)) {
-                        throw new EE_Error(
-                            sprintf(
-                                esc_html__(
-                                    "You used a special where query param %s, but the value isn't an array of where query params, it's just %s'. It should be an array, eg array('EVT_ID'=>23,'OR'=>array('Venue.VNU_ID'=>32,'Venue.VNU_name'=>'monkey_land'))",
-                                    "event_espresso"
-                                ),
-                                $param,
-                                $possibly_array_of_params
-                            )
-                        );
-                    }
-                    $this->_extract_related_models_from_sub_params_array_keys(
-                        $possibly_array_of_params,
-                        $model_query_info_carrier,
-                        $query_param_type
-                    );
-                } elseif (
-                    $query_param_type === 0 // ie WHERE
-                    && is_array($possibly_array_of_params)
-                    && isset($possibly_array_of_params[2])
-                    && $possibly_array_of_params[2] == true
-                ) {
-                    // then $possible_array_of_params looks something like array('<','DTT_sold',true)
-                    // indicating that $possible_array_of_params[1] is actually a field name,
-                    // from which we should extract query parameters!
-                    if (! isset($possibly_array_of_params[0], $possibly_array_of_params[1])) {
-                        throw new EE_Error(
-                            sprintf(
-                                esc_html__(
-                                    "Improperly formed query parameter %s. It should be numerically indexed like array('<','DTT_sold',true); but you provided %s",
-                                    "event_espresso"
-                                ),
-                                $query_param_type,
-                                implode(",", $possibly_array_of_params)
-                            )
-                        );
-                    }
-                    $this->_extract_related_model_info_from_query_param(
-                        $possibly_array_of_params[1],
-                        $model_query_info_carrier,
-                        $query_param_type
-                    );
-                }
-            }
-        }
-        return $model_query_info_carrier;
-    }
-
-
-    /**
-     * For extracting related models from forced_joins, where the array values contain the info about what
-     * models to join with. Eg an array like array('Attendee','Price.Price_Type');
-     *
-     * @param array                       $sub_query_params @see
-     *                                                      https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @param EE_Model_Query_Info_Carrier $model_query_info_carrier
-     * @param string                      $query_param_type one of $this->_allowed_query_params
-     * @return EE_Model_Query_Info_Carrier
-     * @throws EE_Error
-     */
-    private function _extract_related_models_from_sub_params_array_values(
-        $sub_query_params,
-        EE_Model_Query_Info_Carrier $model_query_info_carrier,
-        $query_param_type
-    ) {
-        if (! empty($sub_query_params)) {
-            if (! is_array($sub_query_params)) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__("Query parameter %s should be an array, but it isn't.", "event_espresso"),
-                        $sub_query_params
-                    )
-                );
-            }
-            foreach ($sub_query_params as $param) {
-                // $param could be simply 'EVT_ID', or it could be 'Registrations.REG_ID', or even 'Registrations.Transactions.Payments.PAY_amount'
-                $this->_extract_related_model_info_from_query_param(
-                    $param,
-                    $model_query_info_carrier,
-                    $query_param_type
-                );
-            }
-        }
-        return $model_query_info_carrier;
-    }
-
-
-    /**
-     * Extract all the query parts from  model query params
-     * and put into a EEM_Related_Model_Info_Carrier for easy extraction into a query. We create this object
-     * instead of directly constructing the SQL because often we need to extract info from the $query_params
-     * but use them in a different order. Eg, we need to know what models we are querying
-     * before we know what joins to perform. However, we need to know what data types correspond to which fields on
-     * other models before we can finalize the where clause SQL.
-     *
-     * @param array $query_params @see
-     *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Model_Query_Info_Carrier
-     * @throws EE_Error
-     * @throws ModelConfigurationException*@throws ReflectionException
-     * @throws ReflectionException
-     */
-    public function _create_model_query_info_carrier($query_params)
-    {
-        if (! is_array($query_params)) {
-            EE_Error::doing_it_wrong(
-                'EEM_Base::_create_model_query_info_carrier',
-                sprintf(
-                    esc_html__(
-                        '$query_params should be an array, you passed a variable of type %s',
-                        'event_espresso'
-                    ),
-                    gettype($query_params)
-                ),
-                '4.6.0'
-            );
-            $query_params = [];
-        }
-        $query_params[0] = isset($query_params[0]) ? $query_params[0] : [];
-        // first check if we should alter the query to account for caps or not
-        // because the caps might require us to do extra joins
-        if (isset($query_params['caps']) && $query_params['caps'] !== 'none') {
-            $query_params[0] = array_replace_recursive(
-                $query_params[0],
-                $this->caps_where_conditions($query_params['caps'])
-            );
-        }
-
-        // check if we should alter the query to remove data related to protected
-        // custom post types
-        if (isset($query_params['exclude_protected']) && $query_params['exclude_protected'] === true) {
-            $where_param_key_for_password = $this->modelChainAndPassword();
-            // only include if related to a cpt where no password has been set
-            $query_params[0]['OR*nopassword'] = [
-                $where_param_key_for_password       => '',
-                $where_param_key_for_password . '*' => ['IS_NULL'],
-            ];
-        }
-        $query_object = $this->_extract_related_models_from_query($query_params);
-        // verify where_query_params has NO numeric indexes.... that's simply not how you use it!
-        foreach ($query_params[0] as $key => $value) {
-            if (is_int($key)) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            "WHERE query params must NOT be numerically-indexed. You provided the array key '%s' for value '%s' while querying model %s. All the query params provided were '%s' Please read documentation on EEM_Base::get_all.",
-                            "event_espresso"
-                        ),
-                        $key,
-                        var_export($value, true),
-                        var_export($query_params, true),
-                        get_class($this)
-                    )
-                );
-            }
-        }
-        if (
-            array_key_exists('default_where_conditions', $query_params)
-            && ! empty($query_params['default_where_conditions'])
-        ) {
-            $use_default_where_conditions = $query_params['default_where_conditions'];
-        } else {
-            $use_default_where_conditions = EEM_Base::default_where_conditions_all;
-        }
-        $query_params[0] = array_merge(
-            $this->_get_default_where_conditions_for_models_in_query(
-                $query_object,
-                $use_default_where_conditions,
-                $query_params[0]
-            ),
-            $query_params[0]
-        );
-        $query_object->set_where_sql($this->_construct_where_clause($query_params[0]));
-        // if this is a "on_join_limit" then we are limiting on on a specific table in a multi_table join.
-        // So we need to setup a subquery and use that for the main join.
-        // Note for now this only works on the primary table for the model.
-        // So for instance, you could set the limit array like this:
-        // array( 'on_join_limit' => array('Primary_Table_Alias', array(1,10) ) )
-        if (array_key_exists('on_join_limit', $query_params) && ! empty($query_params['on_join_limit'])) {
-            $query_object->set_main_model_join_sql(
-                $this->_construct_limit_join_select(
-                    $query_params['on_join_limit'][0],
-                    $query_params['on_join_limit'][1]
-                )
-            );
-        }
-        // set limit
-        if (array_key_exists('limit', $query_params)) {
-            if (is_array($query_params['limit'])) {
-                if (! isset($query_params['limit'][0], $query_params['limit'][1])) {
-                    $e = sprintf(
-                        esc_html__(
-                            "Invalid DB query. You passed '%s' for the LIMIT, but only the following are valid: an integer, string representing an integer, a string like 'int,int', or an array like array(int,int)",
-                            "event_espresso"
-                        ),
-                        http_build_query($query_params['limit'])
-                    );
-                    throw new EE_Error($e . "|" . $e);
-                }
-                // they passed us an array for the limit. Assume it's like array(50,25), meaning offset by 50, and get 25
-                $query_object->set_limit_sql(" LIMIT " . $query_params['limit'][0] . "," . $query_params['limit'][1]);
-            } elseif (! empty($query_params['limit'])) {
-                $query_object->set_limit_sql(" LIMIT " . $query_params['limit']);
-            }
-        }
-        // set order by
-        if (array_key_exists('order_by', $query_params)) {
-            if (is_array($query_params['order_by'])) {
-                // if they're using 'order_by' as an array, they can't use 'order' (because 'order_by' must
-                // specify whether to ascend or descend on each field. Eg 'order_by'=>array('EVT_ID'=>'ASC'). So
-                // including 'order' wouldn't make any sense if 'order_by' has already specified which way to order!
-                if (array_key_exists('order', $query_params)) {
-                    throw new EE_Error(
-                        sprintf(
-                            esc_html__(
-                                "In querying %s, we are using query parameter 'order_by' as an array (keys:%s,values:%s), and so we can't use query parameter 'order' (value %s). You should just use the 'order_by' parameter ",
-                                "event_espresso"
-                            ),
-                            get_class($this),
-                            implode(", ", array_keys($query_params['order_by'])),
-                            implode(", ", $query_params['order_by']),
-                            $query_params['order']
-                        )
-                    );
-                }
-                $this->_extract_related_models_from_sub_params_array_keys(
-                    $query_params['order_by'],
-                    $query_object,
-                    'order_by'
-                );
-                // assume it's an array of fields to order by
-                $order_array = [];
-                foreach ($query_params['order_by'] as $field_name_to_order_by => $order) {
-                    $order         = $this->_extract_order($order);
-                    $order_array[] = $this->_deduce_column_name_from_query_param($field_name_to_order_by) . SP . $order;
-                }
-                $query_object->set_order_by_sql(" ORDER BY " . implode(",", $order_array));
-            } elseif (! empty($query_params['order_by'])) {
-                $this->_extract_related_model_info_from_query_param(
-                    $query_params['order_by'],
-                    $query_object,
-                    'order',
-                    $query_params['order_by']
-                );
-                $order = isset($query_params['order'])
-                    ? $this->_extract_order($query_params['order'])
-                    : 'DESC';
-                $query_object->set_order_by_sql(
-                    " ORDER BY " . $this->_deduce_column_name_from_query_param($query_params['order_by']) . SP . $order
-                );
-            }
-        }
-        // if 'order_by' wasn't set, maybe they are just using 'order' on its own?
-        if (
-            ! array_key_exists('order_by', $query_params)
-            && array_key_exists('order', $query_params)
-            && ! empty($query_params['order'])
-        ) {
-            $pk_field = $this->get_primary_key_field();
-            $order    = $this->_extract_order($query_params['order']);
-            $query_object->set_order_by_sql(" ORDER BY " . $pk_field->get_qualified_column() . SP . $order);
-        }
-        // set group by
-        if (array_key_exists('group_by', $query_params)) {
-            if (is_array($query_params['group_by'])) {
-                // it's an array, so assume we'll be grouping by a bunch of stuff
-                $group_by_array = [];
-                foreach ($query_params['group_by'] as $field_name_to_group_by) {
-                    $group_by_array[] = $this->_deduce_column_name_from_query_param($field_name_to_group_by);
-                }
-                $query_object->set_group_by_sql(" GROUP BY " . implode(", ", $group_by_array));
-            } elseif (! empty($query_params['group_by'])) {
-                $query_object->set_group_by_sql(
-                    " GROUP BY " . $this->_deduce_column_name_from_query_param($query_params['group_by'])
-                );
-            }
-        }
-        // set having
-        if (array_key_exists('having', $query_params) && $query_params['having']) {
-            $query_object->set_having_sql($this->_construct_having_clause($query_params['having']));
-        }
-        // now, just verify they didn't pass anything wack
-        foreach ($query_params as $query_key => $query_value) {
-            if (! in_array($query_key, $this->_allowed_query_params, true)) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            "You passed %s as a query parameter to %s, which is illegal! The allowed query parameters are %s",
-                            'event_espresso'
-                        ),
-                        $query_key,
-                        get_class($this),
-                        //                      print_r( $this->_allowed_query_params, TRUE )
-                        implode(',', $this->_allowed_query_params)
-                    )
-                );
-            }
-        }
-        $main_model_join_sql = $query_object->get_main_model_join_sql();
-        if (empty($main_model_join_sql)) {
-            $query_object->set_main_model_join_sql($this->_construct_internal_join());
-        }
-        return $query_object;
-    }
-
-
-    /**
-     * Gets the where conditions that should be imposed on the query based on the
-     * context (eg reading frontend, backend, edit or delete).
-     *
-     * @param string $context one of EEM_Base::valid_cap_contexts()
-     * @return array @see
-     *               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @throws EE_Error
-     */
-    public function caps_where_conditions($context = self::caps_read)
-    {
-        EEM_Base::verify_is_valid_cap_context($context);
-        $cap_where_conditions = [];
-        $cap_restrictions     = $this->caps_missing($context);
-        /**
-         * @var $cap_restrictions EE_Default_Where_Conditions[]
-         */
-        foreach ($cap_restrictions as $cap => $restriction_if_no_cap) {
-            $cap_where_conditions = array_replace_recursive(
-                $cap_where_conditions,
-                $restriction_if_no_cap->get_default_where_conditions()
-            );
-        }
-        return apply_filters(
-            'FHEE__EEM_Base__caps_where_conditions__return',
-            $cap_where_conditions,
-            $this,
-            $context,
-            $cap_restrictions
-        );
-    }
-
-
-    /**
-     * Verifies that $should_be_order_string is in $this->_allowed_order_values,
-     * otherwise throws an exception
-     *
-     * @param string $should_be_order_string
-     * @return string either ASC, asc, DESC or desc
-     * @throws EE_Error
-     */
-    private function _extract_order($should_be_order_string)
-    {
-        if (in_array($should_be_order_string, $this->_allowed_order_values)) {
-            return $should_be_order_string;
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    "While performing a query on '%s', tried to use '%s' as an order parameter. ",
-                    "event_espresso"
-                ),
-                get_class($this),
-                $should_be_order_string
-            )
-        );
-    }
-
-
-    /**
-     * Looks at all the models which are included in this query, and asks each
-     * for their universal_where_params, and returns them in the same format as $query_params[0] (where),
-     * so they can be merged
-     *
-     * @param EE_Model_Query_Info_Carrier $query_info_carrier
-     * @param string                      $use_default_where_conditions can be 'none','other_models_only', or 'all'.
-     *                                                                  'none' means NO default where conditions will
-     *                                                                  be used AT ALL during this query.
-     *                                                                  'other_models_only' means default where
-     *                                                                  conditions from other models will be used, but
-     *                                                                  not for this primary model. 'all', the default,
-     *                                                                  means default where conditions will apply as
-     *                                                                  normal
-     * @param array                       $where_query_params           @see
-     *                                                                  https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @throws EE_Error
-     */
-    private function _get_default_where_conditions_for_models_in_query(
-        EE_Model_Query_Info_Carrier $query_info_carrier,
-        $use_default_where_conditions = EEM_Base::default_where_conditions_all,
-        $where_query_params = []
-    ) {
-        $allowed_used_default_where_conditions_values = EEM_Base::valid_default_where_conditions();
-        if (! in_array($use_default_where_conditions, $allowed_used_default_where_conditions_values)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "You passed an invalid value to the query parameter 'default_where_conditions' of '%s'. Allowed values are %s",
-                        "event_espresso"
-                    ),
-                    $use_default_where_conditions,
-                    implode(", ", $allowed_used_default_where_conditions_values)
-                )
-            );
-        }
-        $universal_query_params = [];
-        if ($this->_should_use_default_where_conditions($use_default_where_conditions, true)) {
-            $universal_query_params = $this->_get_default_where_conditions();
-        } elseif ($this->_should_use_minimum_where_conditions($use_default_where_conditions, true)) {
-            $universal_query_params = $this->_get_minimum_where_conditions();
-        }
-        foreach ($query_info_carrier->get_model_names_included() as $model_relation_path => $model_name) {
-            $related_model = $this->get_related_model_obj($model_name);
-            if ($this->_should_use_default_where_conditions($use_default_where_conditions, false)) {
-                $related_model_universal_where_params =
-                    $related_model->_get_default_where_conditions($model_relation_path);
-            } elseif ($this->_should_use_minimum_where_conditions($use_default_where_conditions, false)) {
-                $related_model_universal_where_params =
-                    $related_model->_get_minimum_where_conditions($model_relation_path);
-            } else {
-                // we don't want to add full or even minimum default where conditions from this model, so just continue
-                continue;
-            }
-            $overrides              = $this->_override_defaults_or_make_null_friendly(
-                $related_model_universal_where_params,
-                $where_query_params,
-                $related_model,
-                $model_relation_path
-            );
-            $universal_query_params = EEH_Array::merge_arrays_and_overwrite_keys(
-                $universal_query_params,
-                $overrides
-            );
-        }
-        return $universal_query_params;
-    }
-
-
-    /**
-     * Determines whether or not we should use default where conditions for the model in question
-     * (this model, or other related models).
-     * Basically, we should use default where conditions on this model if they have requested to use them on all models,
-     * this model only, or to use minimum where conditions on all other models and normal where conditions on this one.
-     * We should use default where conditions on related models when they requested to use default where conditions
-     * on all models, or specifically just on other related models
-     *
-     * @param      $default_where_conditions_value
-     * @param bool $for_this_model false means this is for OTHER related models
-     * @return bool
-     */
-    private function _should_use_default_where_conditions($default_where_conditions_value, $for_this_model = true)
-    {
-        return (
-                   $for_this_model
-                   && in_array(
-                       $default_where_conditions_value,
-                       [
-                           EEM_Base::default_where_conditions_all,
-                           EEM_Base::default_where_conditions_this_only,
-                           EEM_Base::default_where_conditions_minimum_others,
-                       ],
-                       true
-                   )
-               )
-               || (
-                   ! $for_this_model
-                   && in_array(
-                       $default_where_conditions_value,
-                       [
-                           EEM_Base::default_where_conditions_all,
-                           EEM_Base::default_where_conditions_others_only,
-                       ],
-                       true
-                   )
-               );
-    }
-
-
-    /**
-     * Determines whether or not we should use default minimum conditions for the model in question
-     * (this model, or other related models).
-     * Basically, we should use minimum where conditions on this model only if they requested all models to use minimum
-     * where conditions.
-     * We should use minimum where conditions on related models if they requested to use minimum where conditions
-     * on this model or others
-     *
-     * @param      $default_where_conditions_value
-     * @param bool $for_this_model false means this is for OTHER related models
-     * @return bool
-     */
-    private function _should_use_minimum_where_conditions($default_where_conditions_value, $for_this_model = true)
-    {
-        return (
-                   $for_this_model
-                   && $default_where_conditions_value === EEM_Base::default_where_conditions_minimum_all
-               )
-               || (
-                   ! $for_this_model
-                   && in_array(
-                       $default_where_conditions_value,
-                       [
-                           EEM_Base::default_where_conditions_minimum_others,
-                           EEM_Base::default_where_conditions_minimum_all,
-                       ],
-                       true
-                   )
-               );
-    }
-
-
-    /**
-     * Checks if any of the defaults have been overridden. If there are any that AREN'T overridden,
-     * then we also add a special where condition which allows for that model's primary key
-     * to be null (which is important for JOINs. Eg, if you want to see all Events ordered by Venue's name,
-     * then Event's with NO Venue won't appear unless you allow VNU_ID to be NULL)
-     *
-     * @param array    $default_where_conditions
-     * @param array    $provided_where_conditions
-     * @param EEM_Base $model
-     * @param string   $model_relation_path like 'Transaction.Payment.'
-     * @return array @see
-     *               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @throws EE_Error
-     */
-    private function _override_defaults_or_make_null_friendly(
-        $default_where_conditions,
-        $provided_where_conditions,
-        $model,
-        $model_relation_path
-    ) {
-        $null_friendly_where_conditions = [];
-        $none_overridden                = true;
-        $or_condition_key_for_defaults  = 'OR*' . get_class($model);
-        foreach ($default_where_conditions as $key => $val) {
-            if (isset($provided_where_conditions[ $key ])) {
-                $none_overridden = false;
-            } else {
-                $null_friendly_where_conditions[ $or_condition_key_for_defaults ]['AND'][ $key ] = $val;
-            }
-        }
-        if ($none_overridden && $default_where_conditions) {
-            if ($model->has_primary_key_field()) {
-                $null_friendly_where_conditions[ $or_condition_key_for_defaults ][ $model_relation_path
-                                                                                   . "."
-                                                                                   . $model->primary_key_name() ] =
-                    ['IS NULL'];
-            }/*else{
+	/**
+	 * Flag to indicate whether the values provided to EEM_Base have already been prepared
+	 * by the model object or not (ie, the model object has used the field's _prepare_for_set function on the values).
+	 * They almost always WILL NOT, but it's not necessarily a requirement.
+	 * For example, if you want to run EEM_Event::instance()->get_all(array(array('EVT_ID'=>$_GET['event_id'])));
+	 *
+	 * @var boolean
+	 */
+	private $_values_already_prepared_by_model_object = 0;
+
+	/**
+	 * when $_values_already_prepared_by_model_object equals this, we assume
+	 * the data is just like form input that needs to have the model fields'
+	 * prepare_for_set and prepare_for_use_in_db called on it
+	 */
+	const not_prepared_by_model_object = 0;
+
+	/**
+	 * when $_values_already_prepared_by_model_object equals this, we
+	 * assume this value is coming from a model object and doesn't need to have
+	 * prepare_for_set called on it, just prepare_for_use_in_db is used
+	 */
+	const prepared_by_model_object = 1;
+
+	/**
+	 * when $_values_already_prepared_by_model_object equals this, we assume
+	 * the values are already to be used in the database (ie no processing is done
+	 * on them by the model's fields)
+	 */
+	const prepared_for_use_in_db = 2;
+
+
+	protected $singular_item = 'Item';
+
+	protected $plural_item   = 'Items';
+
+	/**
+	 * @type EE_Table_Base[] $_tables array of EE_Table objects for defining which tables comprise this model.
+	 */
+	protected $_tables;
+
+	/**
+	 * with two levels: top-level has array keys which are database table aliases (ie, keys in _tables)
+	 * and the value is an array. Each of those sub-arrays have keys of field names (eg 'ATT_ID', which should also be
+	 * variable names on the model objects (eg, EE_Attendee), and the keys should be children of EE_Model_Field
+	 *
+	 * @var EE_Model_Field_Base[][] $_fields
+	 */
+	protected $_fields;
+
+	/**
+	 * array of different kinds of relations
+	 *
+	 * @var EE_Model_Relation_Base[] $_model_relations
+	 */
+	protected $_model_relations = [];
+
+	/**
+	 * @var EE_Index[] $_indexes
+	 */
+	protected $_indexes = [];
+
+	/**
+	 * Default strategy for getting where conditions on this model. This strategy is used to get default
+	 * where conditions which are added to get_all, update, and delete queries. They can be overridden
+	 * by setting the same columns as used in these queries in the query yourself.
+	 *
+	 * @var EE_Default_Where_Conditions
+	 */
+	protected $_default_where_conditions_strategy;
+
+	/**
+	 * Strategy for getting conditions on this model when 'default_where_conditions' equals 'minimum'.
+	 * This is particularly useful when you want something between 'none' and 'default'
+	 *
+	 * @var EE_Default_Where_Conditions
+	 */
+	protected $_minimum_where_conditions_strategy;
+
+	/**
+	 * String describing how to find the "owner" of this model's objects.
+	 * When there is a foreign key on this model to the wp_users table, this isn't needed.
+	 * But when there isn't, this indicates which related model, or transiently-related model,
+	 * has the foreign key to the wp_users table.
+	 * Eg, for EEM_Registration this would be 'Event' because registrations are directly
+	 * related to events, and events have a foreign key to wp_users.
+	 * On EEM_Transaction, this would be 'Transaction.Event'
+	 *
+	 * @var string
+	 */
+	protected $_model_chain_to_wp_user = '';
+
+	/**
+	 * String describing how to find the model with a password controlling access to this model. This property has the
+	 * same format as $_model_chain_to_wp_user. This is primarily used by the query param "exclude_protected".
+	 * This value is the path of models to follow to arrive at the model with the password field.
+	 * If it is an empty string, it means this model has the password field. If it is null, it means there is no
+	 * model with a password that should affect reading this on the front-end.
+	 * Eg this is an empty string for the Event model because it has a password.
+	 * This is null for the Registration model, because its event's password has no bearing on whether
+	 * you can read the registration or not on the front-end (it just depends on your capabilities.)
+	 * This is 'Datetime.Event' on the Ticket model, because model queries for tickets that set "exclude_protected"
+	 * should hide tickets for datetimes for events that have a password set.
+	 *
+	 * @var string |null
+	 */
+	protected $model_chain_to_password = null;
+
+	/**
+	 * This is a flag typically set by updates so that we don't load the where strategy on updates because updates
+	 * don't need it (particularly CPT models)
+	 *
+	 * @var bool
+	 */
+	protected $_ignore_where_strategy = false;
+
+	/**
+	 * String used in caps relating to this model. Eg, if the caps relating to this
+	 * model are 'ee_edit_events', 'ee_read_events', etc, it would be 'events'.
+	 *
+	 * @var string. If null it hasn't been initialized yet. If false then we
+	 * have indicated capabilities don't apply to this
+	 */
+	protected $_caps_slug = null;
+
+	/**
+	 * 2d array where top-level keys are one of EEM_Base::valid_cap_contexts(),
+	 * and next-level keys are capability names, and each's value is a
+	 * EE_Default_Where_Condition. If the requester requests to apply caps to the query,
+	 * they specify which context to use (ie, frontend, backend, edit or delete)
+	 * and then each capability in the corresponding sub-array that they're missing
+	 * adds the where conditions onto the query.
+	 *
+	 * @var array
+	 */
+	protected $_cap_restrictions = [
+		self::caps_read       => [],
+		self::caps_read_admin => [],
+		self::caps_edit       => [],
+		self::caps_delete     => [],
+	];
+
+	/**
+	 * Array defining which cap restriction generators to use to create default
+	 * cap restrictions to put in EEM_Base::_cap_restrictions.
+	 * Array-keys are one of EEM_Base::valid_cap_contexts(), and values are a child of
+	 * EE_Restriction_Generator_Base. If you don't want any cap restrictions generated
+	 * automatically set this to false (not just null).
+	 *
+	 * @var EE_Restriction_Generator_Base[]
+	 */
+	protected $_cap_restriction_generators = [];
+
+	/**
+	 * constants used to categorize capability restrictions on EEM_Base::_caps_restrictions
+	 */
+	const caps_read       = 'read';
+
+	const caps_read_admin = 'read_admin';
+
+	const caps_edit       = 'edit';
+
+	const caps_delete     = 'delete';
+
+	/**
+	 * Keys are all the cap contexts (ie constants EEM_Base::_caps_*) and values are their 'action'
+	 * as how they'd be used in capability names. Eg EEM_Base::caps_read ('read_frontend')
+	 * maps to 'read' because when looking for relevant permissions we're going to use
+	 * 'read' in teh capabilities names like 'ee_read_events' etc.
+	 *
+	 * @var array
+	 */
+	protected $_cap_contexts_to_cap_action_map = [
+		self::caps_read       => 'read',
+		self::caps_read_admin => 'read',
+		self::caps_edit       => 'edit',
+		self::caps_delete     => 'delete',
+	];
+
+	/**
+	 * Timezone
+	 * This gets set via the constructor so that we know what timezone incoming strings|timestamps are in when there
+	 * are EE_Datetime_Fields in use.  This can also be used before a get to set what timezone you want strings coming
+	 * out of the created objects.  NOT all EEM_Base child classes use this property but any that use a
+	 * EE_Datetime_Field data type will have access to it.
+	 *
+	 * @var string
+	 */
+	protected $_timezone;
+
+
+	/**
+	 * This holds the id of the blog currently making the query.  Has no bearing on single site but is used for
+	 * multisite.
+	 *
+	 * @var int
+	 */
+	protected static $_model_query_blog_id;
+
+	/**
+	 * A copy of _fields, except the array keys are the model names pointed to by
+	 * the field
+	 *
+	 * @var EE_Model_Field_Base[]
+	 */
+	private $_cache_foreign_key_to_fields = [];
+
+	/**
+	 * Cached list of all the fields on the model, indexed by their name
+	 *
+	 * @var EE_Model_Field_Base[]
+	 */
+	private $_cached_fields = null;
+
+	/**
+	 * Cached list of all the fields on the model, except those that are
+	 * marked as only pertinent to the database
+	 *
+	 * @var EE_Model_Field_Base[]
+	 */
+	private $_cached_fields_non_db_only = null;
+
+	/**
+	 * A cached reference to the primary key for quick lookup
+	 *
+	 * @var EE_Model_Field_Base
+	 */
+	private $_primary_key_field = null;
+
+	/**
+	 * Flag indicating whether this model has a primary key or not
+	 *
+	 * @var boolean
+	 */
+	protected $_has_primary_key_field = null;
+
+	/**
+	 * array in the format:  [ FK alias => full PK ]
+	 * where keys are local column name aliases for foreign keys
+	 * and values are the fully qualified column name for the primary key they represent
+	 *  ex:
+	 *      [ 'Event.EVT_wp_user' => 'WP_User.ID' ]
+	 *
+	 * @var array $foreign_key_aliases
+	 */
+	protected $foreign_key_aliases = [];
+
+	/**
+	 * Whether or not this model is based off a table in WP core only (CPTs should set
+	 * this to FALSE, but if we were to make an EE_WP_Post model, it should set this to true).
+	 * This should be true for models that deal with data that should exist independent of EE.
+	 * For example, if the model can read and insert data that isn't used by EE, this should be true.
+	 * It would be false, however, if you could guarantee the model would only interact with EE data,
+	 * even if it uses a WP core table (eg event and venue models set this to false for that reason:
+	 * they can only read and insert events and venues custom post types, not arbitrary post types)
+	 *
+	 * @var boolean
+	 */
+	protected $_wp_core_model = false;
+
+	/**
+	 * @var bool stores whether this model has a password field or not.
+	 * null until initialized by hasPasswordField()
+	 */
+	protected $has_password_field;
+
+	/**
+	 * @var EE_Password_Field|null Automatically set when calling getPasswordField()
+	 */
+	protected $password_field;
+
+	/**
+	 *    List of valid operators that can be used for querying.
+	 * The keys are all operators we'll accept, the values are the real SQL
+	 * operators used
+	 *
+	 * @var array
+	 */
+	protected $_valid_operators = [
+		'='           => '=',
+		'<='          => '<=',
+		'<'           => '<',
+		'>='          => '>=',
+		'>'           => '>',
+		'!='          => '!=',
+		'LIKE'        => 'LIKE',
+		'like'        => 'LIKE',
+		'NOT_LIKE'    => 'NOT LIKE',
+		'not_like'    => 'NOT LIKE',
+		'NOT LIKE'    => 'NOT LIKE',
+		'not like'    => 'NOT LIKE',
+		'IN'          => 'IN',
+		'in'          => 'IN',
+		'NOT_IN'      => 'NOT IN',
+		'not_in'      => 'NOT IN',
+		'NOT IN'      => 'NOT IN',
+		'not in'      => 'NOT IN',
+		'between'     => 'BETWEEN',
+		'BETWEEN'     => 'BETWEEN',
+		'IS_NOT_NULL' => 'IS NOT NULL',
+		'is_not_null' => 'IS NOT NULL',
+		'IS NOT NULL' => 'IS NOT NULL',
+		'is not null' => 'IS NOT NULL',
+		'IS_NULL'     => 'IS NULL',
+		'is_null'     => 'IS NULL',
+		'IS NULL'     => 'IS NULL',
+		'is null'     => 'IS NULL',
+		'REGEXP'      => 'REGEXP',
+		'regexp'      => 'REGEXP',
+		'NOT_REGEXP'  => 'NOT REGEXP',
+		'not_regexp'  => 'NOT REGEXP',
+		'NOT REGEXP'  => 'NOT REGEXP',
+		'not regexp'  => 'NOT REGEXP',
+	];
+
+	/**
+	 * operators that work like 'IN', accepting a comma-separated list of values inside brackets. Eg '(1,2,3)'
+	 *
+	 * @var array
+	 */
+	protected $_in_style_operators = ['IN', 'NOT IN'];
+
+	/**
+	 * operators that work like 'BETWEEN'.  Typically used for datetime calculations, i.e. "BETWEEN '12-1-2011' AND
+	 * '12-31-2012'"
+	 *
+	 * @var array
+	 */
+	protected $_between_style_operators = ['BETWEEN'];
+
+	/**
+	 * Operators that work like SQL's like: input should be assumed to be a string, already prepared for a LIKE query.
+	 *
+	 * @var array
+	 */
+	protected $_like_style_operators = ['LIKE', 'NOT LIKE'];
+
+	/**
+	 * operators that are used for handling NUll and !NULL queries.  Typically used for when checking if a row exists
+	 * on a join table.
+	 *
+	 * @var array
+	 */
+	protected $_null_style_operators = ['IS NOT NULL', 'IS NULL'];
+
+	/**
+	 * Allowed values for $query_params['order'] for ordering in queries
+	 *
+	 * @var array
+	 */
+	protected $_allowed_order_values = ['asc', 'desc', 'ASC', 'DESC'];
+
+	/**
+	 * When these are keys in a WHERE or HAVING clause, they are handled much differently
+	 * than regular field names. It is assumed that their values are an array of WHERE conditions
+	 *
+	 * @var array
+	 */
+	private $_logic_query_param_keys = ['not', 'and', 'or', 'NOT', 'AND', 'OR'];
+
+	/**
+	 * Allowed keys in $query_params arrays passed into queries. Note that 0 is meant to always be a
+	 * 'where', but 'where' clauses are so common that we thought we'd omit it
+	 *
+	 * @var array
+	 */
+	private $_allowed_query_params = [
+		0,
+		'limit',
+		'order_by',
+		'group_by',
+		'having',
+		'force_join',
+		'order',
+		'on_join_limit',
+		'default_where_conditions',
+		'caps',
+		'extra_selects',
+		'exclude_protected',
+	];
+
+	/**
+	 * All the data types that can be used in $wpdb->prepare statements.
+	 *
+	 * @var array
+	 */
+	private $_valid_wpdb_data_types = ['%d', '%s', '%f'];
+
+	/**
+	 * @var EE_Registry $EE
+	 */
+	protected $EE = null;
+
+
+	/**
+	 * Property which, when set, will have this model echo out the next X queries to the page for debugging.
+	 *
+	 * @var int
+	 */
+	protected $_show_next_x_db_queries = 0;
+
+	/**
+	 * When using _get_all_wpdb_results, you can specify a custom selection. If you do so,
+	 * it gets saved on this property as an instance of CustomSelects so those selections can be used in
+	 * WHERE, GROUP_BY, etc.
+	 *
+	 * @var CustomSelects
+	 */
+	protected $_custom_selections = [];
+
+	/**
+	 * key => value Entity Map using  array( EEM_Base::$_model_query_blog_id => array( ID => model object ) )
+	 * caches every model object we've fetched from the DB on this request
+	 *
+	 * @var array
+	 */
+	protected $_entity_map;
+
+	/**
+	 * @var LoaderInterface
+	 */
+	protected static $loader;
+
+	/**
+	 * @var Mirror
+	 */
+	private static $mirror;
+
+
+	/**
+	 * constant used to show EEM_Base has not yet verified the db on this http request
+	 */
+	const db_verified_none = 0;
+
+	/**
+	 * constant used to show EEM_Base has verified the EE core db on this http request,
+	 * but not the addons' dbs
+	 */
+	const db_verified_core = 1;
+
+	/**
+	 * constant used to show EEM_Base has verified the addons' dbs (and implicitly
+	 * the EE core db too)
+	 */
+	const db_verified_addons = 2;
+
+	/**
+	 * indicates whether an EEM_Base child has already re-verified the DB
+	 * is ok (we don't want to do it repetitively). Should be set to one the constants
+	 * looking like EEM_Base::db_verified_*
+	 *
+	 * @var int - 0 = none, 1 = core, 2 = addons
+	 */
+	protected static $_db_verification_level = EEM_Base::db_verified_none;
+
+	/**
+	 * @const constant for 'default_where_conditions' to apply default where conditions to ALL queried models
+	 *        (eg, if retrieving registrations ordered by their datetimes, this will only return non-trashed
+	 *        registrations for non-trashed tickets for non-trashed datetimes)
+	 */
+	const default_where_conditions_all = 'all';
+
+	/**
+	 * @const constant for 'default_where_conditions' to apply default where conditions to THIS model only, but
+	 *        no other models which are joined to (eg, if retrieving registrations ordered by their datetimes, this will
+	 *        return non-trashed registrations, regardless of the related datetimes and tickets' statuses).
+	 *        It is preferred to use EEM_Base::default_where_conditions_minimum_others because, when joining to
+	 *        models which share tables with other models, this can return data for the wrong model.
+	 */
+	const default_where_conditions_this_only = 'this_model_only';
+
+	/**
+	 * @const constant for 'default_where_conditions' to apply default where conditions to other models queried,
+	 *        but not the current model (eg, if retrieving registrations ordered by their datetimes, this will
+	 *        return all registrations related to non-trashed tickets and non-trashed datetimes)
+	 */
+	const default_where_conditions_others_only = 'other_models_only';
+
+	/**
+	 * @const constant for 'default_where_conditions' to apply minimum where conditions to all models queried.
+	 *        For most models this the same as EEM_Base::default_where_conditions_none, except for models which share
+	 *        their table with other models, like the Event and Venue models. For example, when querying for events
+	 *        ordered by their venues' name, this will be sure to only return real events with associated real venues
+	 *        (regardless of whether those events and venues are trashed)
+	 *        In contrast, using EEM_Base::default_where_conditions_none would could return WP posts other than EE
+	 *        events.
+	 */
+	const default_where_conditions_minimum_all = 'minimum';
+
+	/**
+	 * @const constant for 'default_where_conditions' to apply apply where conditions to other models, and full default
+	 *        where conditions for the queried model (eg, when querying events ordered by venues' names, this will
+	 *        return non-trashed events for any venues, regardless of whether those associated venues are trashed or
+	 *        not)
+	 */
+	const default_where_conditions_minimum_others = 'full_this_minimum_others';
+
+	/**
+	 * @const constant for 'default_where_conditions' to NOT apply any where conditions. This should very rarely be
+	 *        used, because when querying from a model which shares its table with another model (eg Events and Venues)
+	 *        it's possible it will return table entries for other models. You should use
+	 *        EEM_Base::default_where_conditions_minimum_all instead.
+	 */
+	const default_where_conditions_none = 'none';
+
+
+	/**
+	 * About all child constructors:
+	 * they should define the _tables, _fields and _model_relations arrays.
+	 * Should ALWAYS be called after child constructor.
+	 * In order to make the child constructors to be as simple as possible, this parent constructor
+	 * finalizes constructing all the object's attributes.
+	 * Generally, rather than requiring a child to code
+	 * $this->_tables = array(
+	 *        'Event_Post_Table' => new EE_Table('Event_Post_Table','wp_posts')
+	 *        ...);
+	 *  (thus repeating itself in the array key and in the constructor of the new EE_Table,)
+	 * each EE_Table has a function to set the table's alias after the constructor, using
+	 * the array key ('Event_Post_Table'), instead of repeating it. The model fields and model relations
+	 * do something similar.
+	 *
+	 * @param null $timezone
+	 * @throws EE_Error
+	 */
+	protected function __construct($timezone = null)
+	{
+		// check that the model has not been loaded too soon
+		if (! did_action('AHEE__EE_System__load_espresso_addons')) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'The %1$s model can not be loaded before the "AHEE__EE_System__load_espresso_addons" hook has been called. This gives other addons a chance to extend this model.',
+						'event_espresso'
+					),
+					get_class($this)
+				)
+			);
+		}
+		/**
+		 * Set blogid for models to current blog. However we ONLY do this if $_model_query_blog_id is not already set.
+		 */
+		if (empty(EEM_Base::$_model_query_blog_id)) {
+			EEM_Base::set_model_query_blog_id();
+		}
+		/**
+		 * Filters the list of tables on a model. It is best to NOT use this directly and instead
+		 * just use EE_Register_Model_Extension
+		 *
+		 * @var EE_Table_Base[] $_tables
+		 */
+		$this->_tables = (array) apply_filters('FHEE__' . get_class($this) . '__construct__tables', $this->_tables);
+		foreach ($this->_tables as $table_alias => $table_obj) {
+			/** @var $table_obj EE_Table_Base */
+			$table_obj->_construct_finalize_with_alias($table_alias);
+			if ($table_obj instanceof EE_Secondary_Table) {
+				$table_obj->_construct_finalize_set_table_to_join_with($this->_get_main_table());
+			}
+		}
+		/**
+		 * Filters the list of fields on a model. It is best to NOT use this directly and instead just use
+		 * EE_Register_Model_Extension
+		 *
+		 * @param EE_Model_Field_Base[] $_fields
+		 */
+		$this->_fields = (array) apply_filters('FHEE__' . get_class($this) . '__construct__fields', $this->_fields);
+		$this->_invalidate_field_caches();
+		foreach ($this->_fields as $table_alias => $fields_for_table) {
+			if (! array_key_exists($table_alias, $this->_tables)) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							"Table alias %s does not exist in EEM_Base child's _tables array. Only tables defined are %s",
+							'event_espresso'
+						),
+						$table_alias,
+						implode(",", $this->_fields)
+					)
+				);
+			}
+			foreach ($fields_for_table as $field_name => $field_obj) {
+				/** @var $field_obj EE_Model_Field_Base | EE_Primary_Key_Field_Base */
+				// primary key field base has a slightly different _construct_finalize
+				/** @var $field_obj EE_Model_Field_Base */
+				$field_obj->_construct_finalize($table_alias, $field_name, $this->get_this_model_name());
+			}
+		}
+		// everything is related to Extra_Meta
+		if (get_class($this) !== 'EEM_Extra_Meta') {
+			// make extra meta related to everything, but don't block deleting things just
+			// because they have related extra meta info. For now just orphan those extra meta
+			// in the future we should automatically delete them
+			$this->_model_relations['Extra_Meta'] = new EE_Has_Many_Any_Relation(false);
+		}
+		// and change logs
+		if (get_class($this) !== 'EEM_Change_Log') {
+			$this->_model_relations['Change_Log'] = new EE_Has_Many_Any_Relation(false);
+		}
+		/**
+		 * Filters the list of relations on a model. It is best to NOT use this directly and instead just use
+		 * EE_Register_Model_Extension
+		 *
+		 * @param EE_Model_Relation_Base[] $_model_relations
+		 */
+		$this->_model_relations = (array) apply_filters(
+			'FHEE__' . get_class($this) . '__construct__model_relations',
+			$this->_model_relations
+		);
+		foreach ($this->_model_relations as $model_name => $relation_obj) {
+			/** @var $relation_obj EE_Model_Relation_Base */
+			$relation_obj->_construct_finalize_set_models($this->get_this_model_name(), $model_name);
+		}
+		foreach ($this->_indexes as $index_name => $index_obj) {
+			$index_obj->_construct_finalize($index_name, $this->get_this_model_name());
+		}
+		$this->set_timezone($timezone);
+		// finalize default where condition strategy, or set default
+		if (! $this->_default_where_conditions_strategy) {
+			// nothing was set during child constructor, so set default
+			$this->_default_where_conditions_strategy = new EE_Default_Where_Conditions();
+		}
+		$this->_default_where_conditions_strategy->_finalize_construct($this);
+		if (! $this->_minimum_where_conditions_strategy) {
+			// nothing was set during child constructor, so set default
+			$this->_minimum_where_conditions_strategy = new EE_Default_Where_Conditions();
+		}
+		$this->_minimum_where_conditions_strategy->_finalize_construct($this);
+		// if the cap slug hasn't been set, and we haven't set it to false on purpose
+		// to indicate to NOT set it, set it to the logical default
+		if ($this->_caps_slug === null) {
+			$this->_caps_slug = EEH_Inflector::pluralize_and_lower($this->get_this_model_name());
+		}
+		// initialize the standard cap restriction generators if none were specified by the child constructor
+		if (is_array($this->_cap_restriction_generators)) {
+			foreach ($this->cap_contexts_to_cap_action_map() as $cap_context => $action) {
+				if (! isset($this->_cap_restriction_generators[ $cap_context ])) {
+					$this->_cap_restriction_generators[ $cap_context ] = apply_filters(
+						'FHEE__EEM_Base___construct__standard_cap_restriction_generator',
+						new EE_Restriction_Generator_Protected(),
+						$cap_context,
+						$this
+					);
+				}
+			}
+		}
+		// if there are cap restriction generators, use them to make the default cap restrictions
+		if (is_array($this->_cap_restriction_generators)) {
+			foreach ($this->_cap_restriction_generators as $context => $generator_object) {
+				if (! $generator_object) {
+					continue;
+				}
+				if (! $generator_object instanceof EE_Restriction_Generator_Base) {
+					throw new EE_Error(
+						sprintf(
+							esc_html__(
+								'Index "%1$s" in the model %2$s\'s _cap_restriction_generators is not a child of EE_Restriction_Generator_Base. It should be that or NULL.',
+								'event_espresso'
+							),
+							$context,
+							$this->get_this_model_name()
+						)
+					);
+				}
+				$action = $this->cap_action_for_context($context);
+				if (! $generator_object->construction_finalized()) {
+					$generator_object->_construct_finalize($this, $action);
+				}
+			}
+		}
+		do_action('AHEE__' . get_class($this) . '__construct__end');
+	}
+
+
+	/**
+	 * @return LoaderInterface
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected static function getLoader(): LoaderInterface
+	{
+		if (! EEM_Base::$loader instanceof LoaderInterface) {
+			EEM_Base::$loader = LoaderFactory::getLoader();
+		}
+		return EEM_Base::$loader;
+	}
+
+
+	/**
+	 * @return Mirror
+	 * @since   $VID:$
+	 */
+	private static function getMirror(): Mirror
+	{
+		if (! EEM_Base::$mirror instanceof Mirror) {
+			EEM_Base::$mirror = EEM_Base::getLoader()->getShared(Mirror::class);
+		}
+		return EEM_Base::$mirror;
+	}
+
+
+	/**
+	 * @param string $model_class_Name
+	 * @param string $timezone
+	 * @return array
+	 * @throws ReflectionException
+	 * @since   $VID:$
+	 */
+	private static function getModelArguments(string $model_class_Name, string $timezone): array
+	{
+		$arguments = [$timezone];
+		$params    = EEM_Base::getMirror()->getParameters($model_class_Name);
+		if (count($params) > 1) {
+			if ($params[1]->getName() === 'model_field_factory') {
+				$arguments = [
+					$timezone,
+					EEM_Base::getLoader()->getShared(ModelFieldFactory::class),
+				];
+			} elseif ($model_class_Name === 'EEM_Form_Section') {
+				$arguments = [
+					EEM_Base::getLoader()->getShared('EventEspresso\core\services\form\meta\FormStatus'),
+					$timezone,
+				];
+			} elseif ($model_class_Name === 'EEM_Form_Element') {
+				$arguments = [
+					EEM_Base::getLoader()->getShared('EventEspresso\core\services\form\meta\FormStatus'),
+					EEM_Base::getLoader()->getShared('EventEspresso\core\services\form\meta\InputTypes'),
+					$timezone,
+				];
+			}
+		}
+		return $arguments;
+	}
+
+
+	/**
+	 * This function is a singleton method used to instantiate the Espresso_model object
+	 *
+	 * @param string|null $timezone   string representing the timezone we want to set for returned Date Time Strings
+	 *                                (and any incoming timezone data that gets saved).
+	 *                                Note this just sends the timezone info to the date time model field objects.
+	 *                                Default is NULL
+	 *                                (and will be assumed using the set timezone in the 'timezone_string' wp option)
+	 * @return static (as in the concrete child class)
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function instance($timezone = null)
+	{
+		// check if instance of Espresso_model already exists
+		if (! static::$_instance instanceof static) {
+			$arguments = EEM_Base::getModelArguments(static::class, (string) $timezone);
+			$model     = new static(...$arguments);
+			EEM_Base::getLoader()->share(static::class, $model, $arguments);
+			static::$_instance = $model;
+		}
+		// we might have a timezone set, let set_timezone decide what to do with it
+		if ($timezone) {
+			static::$_instance->set_timezone($timezone);
+		}
+		// Espresso_model object
+		return static::$_instance;
+	}
+
+
+	/**
+	 * resets the model and returns it
+	 *
+	 * @param string|null $timezone
+	 * @return EEM_Base|null (if the model was already instantiated, returns it, with
+	 * all its properties reset; if it wasn't instantiated, returns null)
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public static function reset($timezone = null)
+	{
+		if (! static::$_instance instanceof EEM_Base) {
+			return null;
+		}
+		// Let's NOT swap out the current instance for a new one
+		// because if someone has a reference to it, we can't remove their reference.
+		// It's best to keep using the same reference but change the original object instead,
+		// so reset all its properties to their original values as defined in the class.
+		$static_properties = EEM_Base::getMirror()->getStaticProperties(static::class);
+		foreach (EEM_Base::getMirror()->getDefaultProperties(static::class) as $property => $value) {
+			// don't set instance to null like it was originally,
+			// but it's static anyways, and we're ignoring static properties (for now at least)
+			if (! isset($static_properties[ $property ])) {
+				static::$_instance->{$property} = $value;
+			}
+		}
+		// and then directly call its constructor again, like we would if we were creating a new one
+		$arguments = EEM_Base::getModelArguments(static::class, (string) $timezone);
+		static::$_instance->__construct(...$arguments);
+		return self::instance();
+	}
+
+
+	/**
+	 * Used to set the $_model_query_blog_id static property.
+	 *
+	 * @param int $blog_id  If provided then will set the blog_id for the models to this id.  If not provided then the
+	 *                      value for get_current_blog_id() will be used.
+	 */
+	public static function set_model_query_blog_id($blog_id = 0)
+	{
+		EEM_Base::$_model_query_blog_id = $blog_id > 0
+			? (int) $blog_id
+			: get_current_blog_id();
+	}
+
+
+	/**
+	 * Returns whatever is set as the internal $model_query_blog_id.
+	 *
+	 * @return int
+	 */
+	public static function get_model_query_blog_id()
+	{
+		return EEM_Base::$_model_query_blog_id;
+	}
+
+
+	/**
+	 * retrieve the status details from esp_status table as an array IF this model has the status table as a relation.
+	 *
+	 * @param boolean $translated return localized strings or JUST the array.
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function status_array($translated = false)
+	{
+		if (! array_key_exists('Status', $this->_model_relations)) {
+			return [];
+		}
+		$model_name   = $this->get_this_model_name();
+		$status_type  = str_replace(' ', '_', strtolower(str_replace('_', ' ', $model_name)));
+		$stati        = EEM_Status::instance()->get_all([['STS_type' => $status_type]]);
+		$status_array = [];
+		foreach ($stati as $status) {
+			$status_array[ $status->ID() ] = $status->get('STS_code');
+		}
+		return $translated
+			? EEM_Status::instance()->localized_status($status_array, false, 'sentence')
+			: $status_array;
+	}
+
+
+	/**
+	 * Gets all the EE_Base_Class objects which match the $query_params, by querying the DB.
+	 *
+	 * @param array $query_params             @see
+	 *                                        https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 *                                        or if you have the development copy of EE you can view this at the path:
+	 *                                        /docs/G--Model-System/model-query-params.md
+	 * @return EE_Base_Class[]  *note that there is NO option to pass the output type. If you want results different
+	 *                                        from EE_Base_Class[], use get_all_wpdb_results(). Array keys are object
+	 *                                        IDs (if there is a primary key on the model. if not, numerically indexed)
+	 *                                        Some full examples: get 10 transactions which have Scottish attendees:
+	 *                                        EEM_Transaction::instance()->get_all( array( array(
+	 *                                        'OR'=>array(
+	 *                                        'Registration.Attendee.ATT_fname'=>array('like','Mc%'),
+	 *                                        'Registration.Attendee.ATT_fname*other'=>array('like','Mac%')
+	 *                                        )
+	 *                                        ),
+	 *                                        'limit'=>10,
+	 *                                        'group_by'=>'TXN_ID'
+	 *                                        ));
+	 *                                        get all the answers to the question titled "shirt size" for event with id
+	 *                                        12, ordered by their answer EEM_Answer::instance()->get_all(array( array(
+	 *                                        'Question.QST_display_text'=>'shirt size',
+	 *                                        'Registration.Event.EVT_ID'=>12
+	 *                                        ),
+	 *                                        'order_by'=>array('ANS_value'=>'ASC')
+	 *                                        ));
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_all($query_params = [])
+	{
+		if (
+			isset($query_params['limit'])
+			&& ! isset($query_params['group_by'])
+		) {
+			$query_params['group_by'] = array_keys($this->get_combined_primary_key_fields());
+		}
+		return $this->_create_objects($this->_get_all_wpdb_results($query_params));
+	}
+
+
+	/**
+	 * Modifies the query parameters so we only get back model objects
+	 * that "belong" to the current user
+	 *
+	 * @param array $query_params @see
+	 *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return array @see
+	 *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 */
+	public function alter_query_params_to_only_include_mine($query_params = [])
+	{
+		$wp_user_field_name = $this->wp_user_field_name();
+		if ($wp_user_field_name) {
+			$query_params[0][ $wp_user_field_name ] = get_current_user_id();
+		}
+		return $query_params;
+	}
+
+
+	/**
+	 * Returns the name of the field's name that points to the WP_User table
+	 *  on this model (or follows the _model_chain_to_wp_user and uses that model's
+	 * foreign key to the WP_User table)
+	 *
+	 * @return string|boolean string on success, boolean false when there is no
+	 * foreign key to the WP_User table
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 */
+	public function wp_user_field_name()
+	{
+		try {
+			if (! empty($this->_model_chain_to_wp_user)) {
+				$models_to_follow_to_wp_users = explode('.', $this->_model_chain_to_wp_user);
+				$last_model_name              = end($models_to_follow_to_wp_users);
+				$model_with_fk_to_wp_users    = EE_Registry::instance()->load_model($last_model_name);
+				$model_chain_to_wp_user       = $this->_model_chain_to_wp_user . '.';
+			} else {
+				$model_with_fk_to_wp_users = $this;
+				$model_chain_to_wp_user    = '';
+			}
+			$wp_user_field = $model_with_fk_to_wp_users->get_foreign_key_to('WP_User');
+			return $model_chain_to_wp_user . $wp_user_field->get_name();
+		} catch (EE_Error $e) {
+			return false;
+		}
+	}
+
+
+	/**
+	 * Returns the _model_chain_to_wp_user string, which indicates which related model
+	 * (or transiently-related model) has a foreign key to the wp_users table;
+	 * useful for finding if model objects of this type are 'owned' by the current user.
+	 * This is an empty string when the foreign key is on this model and when it isn't,
+	 * but is only non-empty when this model's ownership is indicated by a RELATED model
+	 * (or transiently-related model)
+	 *
+	 * @return string
+	 */
+	public function model_chain_to_wp_user()
+	{
+		return $this->_model_chain_to_wp_user;
+	}
+
+
+	/**
+	 * Whether this model is 'owned' by a specific wordpress user (even indirectly,
+	 * like how registrations don't have a foreign key to wp_users, but the
+	 * events they are for are), or is unrelated to wp users.
+	 * generally available
+	 *
+	 * @return boolean
+	 */
+	public function is_owned()
+	{
+		if ($this->model_chain_to_wp_user()) {
+			return true;
+		}
+		try {
+			$this->get_foreign_key_to('WP_User');
+			return true;
+		} catch (EE_Error $e) {
+			return false;
+		}
+	}
+
+
+	/**
+	 * Used internally to get WPDB results, because other functions, besides get_all, may want to do some queries, but
+	 * may want to preserve the WPDB results (eg, update, which first queries to make sure we have all the tables on
+	 * the model)
+	 *
+	 * @param array  $query_params      @see
+	 *                                  https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $output            ARRAY_A, OBJECT_K, etc. Just like
+	 * @param mixed  $columns_to_select , What columns to select. By default, we select all columns specified by the
+	 *                                  fields on the model, and the models we joined to in the query. However, you can
+	 *                                  override this and set the select to "*", or a specific column name, like
+	 *                                  "ATT_ID", etc. If you would like to use these custom selections in WHERE,
+	 *                                  GROUP_BY, or HAVING clauses, you must instead provide an array. Array keys are
+	 *                                  the aliases used to refer to this selection, and values are to be
+	 *                                  numerically-indexed arrays, where 0 is the selection and 1 is the data type.
+	 *                                  Eg, array('count'=>array('COUNT(REG_ID)','%d'))
+	 * @return array | stdClass[] like results of $wpdb->get_results($sql,OBJECT), (ie, output type is OBJECT)
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 */
+	protected function _get_all_wpdb_results($query_params = [], $output = ARRAY_A, $columns_to_select = null)
+	{
+		$this->_custom_selections = $this->getCustomSelection($query_params, $columns_to_select);
+		$model_query_info         = $this->_create_model_query_info_carrier($query_params);
+		$select_expressions       = $columns_to_select === null
+			? $this->_construct_default_select_sql($model_query_info)
+			: '';
+		if ($this->_custom_selections instanceof CustomSelects) {
+			$custom_expressions = $this->_custom_selections->columnsToSelectExpression();
+			$select_expressions .= $select_expressions
+				? ', ' . $custom_expressions
+				: $custom_expressions;
+		}
+
+		$SQL = "SELECT $select_expressions " . $this->_construct_2nd_half_of_select_query($model_query_info);
+		return $this->_do_wpdb_query('get_results', [$SQL, $output]);
+	}
+
+
+	/**
+	 * Get a CustomSelects object if the $query_params or $columns_to_select allows for it.
+	 * Note: $query_params['extra_selects'] will always override any $columns_to_select values. It is the preferred
+	 * method of including extra select information.
+	 *
+	 * @param array             $query_params
+	 * @param null|array|string $columns_to_select
+	 * @return null|CustomSelects
+	 * @throws InvalidArgumentException
+	 */
+	protected function getCustomSelection(array $query_params, $columns_to_select = null)
+	{
+		if (! isset($query_params['extra_selects']) && $columns_to_select === null) {
+			return null;
+		}
+		$selects = isset($query_params['extra_selects']) ? $query_params['extra_selects'] : $columns_to_select;
+		$selects = is_string($selects) ? explode(',', $selects) : $selects;
+		return new CustomSelects($selects);
+	}
+
+
+	/**
+	 * Gets an array of rows from the database just like $wpdb->get_results would,
+	 * but you can use the model query params to more easily
+	 * take care of joins, field preparation etc.
+	 *
+	 * @param array  $query_params      @see
+	 *                                  https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $output            ARRAY_A, OBJECT_K, etc. Just like
+	 * @param mixed  $columns_to_select , What columns to select. By default, we select all columns specified by the
+	 *                                  fields on the model, and the models we joined to in the query. However, you can
+	 *                                  override this and set the select to "*", or a specific column name, like
+	 *                                  "ATT_ID", etc. If you would like to use these custom selections in WHERE,
+	 *                                  GROUP_BY, or HAVING clauses, you must instead provide an array. Array keys are
+	 *                                  the aliases used to refer to this selection, and values are to be
+	 *                                  numerically-indexed arrays, where 0 is the selection and 1 is the data type.
+	 *                                  Eg, array('count'=>array('COUNT(REG_ID)','%d'))
+	 * @return array|stdClass[] like results of $wpdb->get_results($sql,OBJECT), (ie, output type is OBJECT)
+	 * @throws EE_Error
+	 */
+	public function get_all_wpdb_results($query_params = [], $output = ARRAY_A, $columns_to_select = null)
+	{
+		return $this->_get_all_wpdb_results($query_params, $output, $columns_to_select);
+	}
+
+
+	/**
+	 * For creating a custom select statement
+	 *
+	 * @param mixed $columns_to_select either a string to be inserted directly as the select statement,
+	 *                                 or an array where keys are aliases, and values are arrays where 0=>the selection
+	 *                                 SQL, and 1=>is the datatype
+	 * @return string
+	 * @throws EE_Error
+	 */
+	private function _construct_select_from_input($columns_to_select)
+	{
+		if (is_array($columns_to_select)) {
+			$select_sql_array = [];
+			foreach ($columns_to_select as $alias => $selection_and_datatype) {
+				if (! is_array($selection_and_datatype) || ! isset($selection_and_datatype[1])) {
+					throw new EE_Error(
+						sprintf(
+							esc_html__(
+								"Custom selection %s (alias %s) needs to be an array like array('COUNT(REG_ID)','%%d')",
+								'event_espresso'
+							),
+							$selection_and_datatype,
+							$alias
+						)
+					);
+				}
+				if (! in_array($selection_and_datatype[1], $this->_valid_wpdb_data_types, true)) {
+					throw new EE_Error(
+						sprintf(
+							esc_html__(
+								"Datatype %s (for selection '%s' and alias '%s') is not a valid wpdb datatype (eg %%s)",
+								'event_espresso'
+							),
+							$selection_and_datatype[1],
+							$selection_and_datatype[0],
+							$alias,
+							implode(', ', $this->_valid_wpdb_data_types)
+						)
+					);
+				}
+				$select_sql_array[] = "{$selection_and_datatype[0]} AS $alias";
+			}
+			$columns_to_select_string = implode(', ', $select_sql_array);
+		} else {
+			$columns_to_select_string = $columns_to_select;
+		}
+		return $columns_to_select_string;
+	}
+
+
+	/**
+	 * Convenient wrapper for getting the primary key field's name. Eg, on Registration, this would be 'REG_ID'
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function primary_key_name()
+	{
+		return $this->get_primary_key_field()->get_name();
+	}
+
+
+	/**
+	 * Gets a single item for this model from the DB, given only its ID (or null if none is found).
+	 * If there is no primary key on this model, $id is treated as primary key string
+	 *
+	 * @param mixed $id int or string, depending on the type of the model's primary key
+	 * @return EE_Base_Class|mixed|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_one_by_ID($id)
+	{
+		if ($this->get_from_entity_map($id)) {
+			return $this->get_from_entity_map($id);
+		}
+		$model_object = $this->get_one(
+			$this->alter_query_params_to_restrict_by_ID(
+				$id,
+				['default_where_conditions' => EEM_Base::default_where_conditions_minimum_all]
+			)
+		);
+		$className    = $this->_get_class_name();
+		if ($model_object instanceof $className) {
+			// make sure valid objects get added to the entity map
+			// so that the next call to this method doesn't trigger another trip to the db
+			$this->add_to_entity_map($model_object);
+		}
+		return $model_object;
+	}
+
+
+	/**
+	 * Alters query parameters to only get items with this ID are returned.
+	 * Takes into account that the ID might be a string produced by EEM_Base::get_index_primary_key_string(),
+	 * or could just be a simple primary key ID
+	 *
+	 * @param int   $id
+	 * @param array $query_params
+	 * @return array of normal query params, @see
+	 *               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @throws EE_Error
+	 */
+	public function alter_query_params_to_restrict_by_ID($id, $query_params = [])
+	{
+		if (! isset($query_params[0])) {
+			$query_params[0] = [];
+		}
+		$conditions_from_id = $this->parse_index_primary_key_string($id);
+		if ($conditions_from_id === null) {
+			$query_params[0][ $this->primary_key_name() ] = $id;
+		} else {
+			// no primary key, so the $id must be from the get_index_primary_key_string()
+			$query_params[0] = array_replace_recursive($query_params[0], $this->parse_index_primary_key_string($id));
+		}
+		return $query_params;
+	}
+
+
+	/**
+	 * Gets a single item for this model from the DB, given the $query_params. Only returns a single class, not an
+	 * array. If no item is found, null is returned.
+	 *
+	 * @param array $query_params like EEM_Base's $query_params variable.
+	 * @return EE_Base_Class|EE_Soft_Delete_Base_Class|NULL
+	 * @throws EE_Error
+	 */
+	public function get_one($query_params = [])
+	{
+		if (! is_array($query_params)) {
+			EE_Error::doing_it_wrong(
+				'EEM_Base::get_one',
+				sprintf(
+					esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
+					gettype($query_params)
+				),
+				'4.6.0'
+			);
+			$query_params = [];
+		}
+		$query_params['limit'] = 1;
+		$items                 = $this->get_all($query_params);
+		if (empty($items)) {
+			return null;
+		}
+		return array_shift($items);
+	}
+
+
+	/**
+	 * Returns the next x number of items in sequence from the given value as
+	 * found in the database matching the given query conditions.
+	 *
+	 * @param mixed $current_field_value    Value used for the reference point.
+	 * @param null  $field_to_order_by      What field is used for the
+	 *                                      reference point.
+	 * @param int   $limit                  How many to return.
+	 * @param array $query_params           Extra conditions on the query.
+	 * @param null  $columns_to_select      If left null, then an array of
+	 *                                      EE_Base_Class objects is returned,
+	 *                                      otherwise you can indicate just the
+	 *                                      columns you want returned.
+	 * @return EE_Base_Class[]|array
+	 * @throws EE_Error
+	 */
+	public function next_x(
+		$current_field_value,
+		$field_to_order_by = null,
+		$limit = 1,
+		$query_params = [],
+		$columns_to_select = null
+	) {
+		return $this->_get_consecutive(
+			$current_field_value,
+			'>',
+			$field_to_order_by,
+			$limit,
+			$query_params,
+			$columns_to_select
+		);
+	}
+
+
+	/**
+	 * Returns the previous x number of items in sequence from the given value
+	 * as found in the database matching the given query conditions.
+	 *
+	 * @param mixed $current_field_value    Value used for the reference point.
+	 * @param null  $field_to_order_by      What field is used for the
+	 *                                      reference point.
+	 * @param int   $limit                  How many to return.
+	 * @param array $query_params           Extra conditions on the query.
+	 * @param null  $columns_to_select      If left null, then an array of
+	 *                                      EE_Base_Class objects is returned,
+	 *                                      otherwise you can indicate just the
+	 *                                      columns you want returned.
+	 * @return EE_Base_Class[]|array
+	 * @throws EE_Error
+	 */
+	public function previous_x(
+		$current_field_value,
+		$field_to_order_by = null,
+		$limit = 1,
+		$query_params = [],
+		$columns_to_select = null
+	) {
+		return $this->_get_consecutive(
+			$current_field_value,
+			'<',
+			$field_to_order_by,
+			$limit,
+			$query_params,
+			$columns_to_select
+		);
+	}
+
+
+	/**
+	 * Returns the next item in sequence from the given value as found in the
+	 * database matching the given query conditions.
+	 *
+	 * @param mixed $current_field_value    Value used for the reference point.
+	 * @param null  $field_to_order_by      What field is used for the
+	 *                                      reference point.
+	 * @param array $query_params           Extra conditions on the query.
+	 * @param null  $columns_to_select      If left null, then an EE_Base_Class
+	 *                                      object is returned, otherwise you
+	 *                                      can indicate just the columns you
+	 *                                      want and a single array indexed by
+	 *                                      the columns will be returned.
+	 * @return EE_Base_Class|null|array()
+	 * @throws EE_Error
+	 */
+	public function next(
+		$current_field_value,
+		$field_to_order_by = null,
+		$query_params = [],
+		$columns_to_select = null
+	) {
+		$results = $this->_get_consecutive(
+			$current_field_value,
+			'>',
+			$field_to_order_by,
+			1,
+			$query_params,
+			$columns_to_select
+		);
+		return empty($results) ? null : reset($results);
+	}
+
+
+	/**
+	 * Returns the previous item in sequence from the given value as found in
+	 * the database matching the given query conditions.
+	 *
+	 * @param mixed $current_field_value    Value used for the reference point.
+	 * @param null  $field_to_order_by      What field is used for the
+	 *                                      reference point.
+	 * @param array $query_params           Extra conditions on the query.
+	 * @param null  $columns_to_select      If left null, then an EE_Base_Class
+	 *                                      object is returned, otherwise you
+	 *                                      can indicate just the columns you
+	 *                                      want and a single array indexed by
+	 *                                      the columns will be returned.
+	 * @return EE_Base_Class|null|array()
+	 * @throws EE_Error
+	 */
+	public function previous(
+		$current_field_value,
+		$field_to_order_by = null,
+		$query_params = [],
+		$columns_to_select = null
+	) {
+		$results = $this->_get_consecutive(
+			$current_field_value,
+			'<',
+			$field_to_order_by,
+			1,
+			$query_params,
+			$columns_to_select
+		);
+		return empty($results) ? null : reset($results);
+	}
+
+
+	/**
+	 * Returns the a consecutive number of items in sequence from the given
+	 * value as found in the database matching the given query conditions.
+	 *
+	 * @param mixed  $current_field_value   Value used for the reference point.
+	 * @param string $operand               What operand is used for the sequence.
+	 * @param string $field_to_order_by     What field is used for the reference point.
+	 * @param int    $limit                 How many to return.
+	 * @param array  $query_params          Extra conditions on the query.
+	 * @param null   $columns_to_select     If left null, then an array of EE_Base_Class objects is returned,
+	 *                                      otherwise you can indicate just the columns you want returned.
+	 * @return EE_Base_Class[]|array
+	 * @throws EE_Error
+	 */
+	protected function _get_consecutive(
+		$current_field_value,
+		$operand = '>',
+		$field_to_order_by = null,
+		$limit = 1,
+		$query_params = [],
+		$columns_to_select = null
+	) {
+		// if $field_to_order_by is empty then let's assume we're ordering by the primary key.
+		if (empty($field_to_order_by)) {
+			if ($this->has_primary_key_field()) {
+				$field_to_order_by = $this->get_primary_key_field()->get_name();
+			} else {
+				if (WP_DEBUG) {
+					throw new EE_Error(
+						esc_html__(
+							'EEM_Base::_get_consecutive() has been called with no $field_to_order_by argument and there is no primary key on the field.  Please provide the field you would like to use as the base for retrieving the next item(s).',
+							'event_espresso'
+						)
+					);
+				}
+				EE_Error::add_error(
+					esc_html__('There was an error with the query.', 'event_espresso'),
+					__FILE__,
+					__FUNCTION__,
+					__LINE__
+				);
+				return [];
+			}
+		}
+		if (! is_array($query_params)) {
+			EE_Error::doing_it_wrong(
+				'EEM_Base::_get_consecutive',
+				sprintf(
+					esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
+					gettype($query_params)
+				),
+				'4.6.0'
+			);
+			$query_params = [];
+		}
+		// let's add the where query param for consecutive look up.
+		$query_params[0][ $field_to_order_by ] = [$operand, $current_field_value];
+		$query_params['limit']                 = $limit;
+		// set direction
+		$incoming_orderby         = isset($query_params['order_by']) ? (array) $query_params['order_by'] : [];
+		$query_params['order_by'] = $operand === '>'
+			? [$field_to_order_by => 'ASC'] + $incoming_orderby
+			: [$field_to_order_by => 'DESC'] + $incoming_orderby;
+		// if $columns_to_select is empty then that means we're returning EE_Base_Class objects
+		if (empty($columns_to_select)) {
+			return $this->get_all($query_params);
+		}
+		// getting just the fields
+		return $this->_get_all_wpdb_results($query_params, ARRAY_A, $columns_to_select);
+	}
+
+
+	/**
+	 * This sets the _timezone property after model object has been instantiated.
+	 *
+	 * @param null | string $timezone valid PHP DateTimeZone timezone string
+	 */
+	public function set_timezone($timezone)
+	{
+		if ($timezone !== null) {
+			$this->_timezone = $timezone;
+		}
+		// note we need to loop through relations and set the timezone on those objects as well.
+		foreach ($this->_model_relations as $relation) {
+			$relation->set_timezone($timezone);
+		}
+		// and finally we do the same for any datetime fields
+		foreach ($this->_fields as $field) {
+			if ($field instanceof EE_Datetime_Field) {
+				$field->set_timezone($timezone);
+			}
+		}
+	}
+
+
+	/**
+	 * This just returns whatever is set for the current timezone.
+	 *
+	 * @access public
+	 * @return string
+	 */
+	public function get_timezone()
+	{
+		// first validate if timezone is set.  If not, then let's set it be whatever is set on the model fields.
+		if (empty($this->_timezone)) {
+			foreach ($this->_fields as $field) {
+				if ($field instanceof EE_Datetime_Field) {
+					$this->set_timezone($field->get_timezone());
+					break;
+				}
+			}
+		}
+		// if timezone STILL empty then return the default timezone for the site.
+		if (empty($this->_timezone)) {
+			$this->set_timezone(EEH_DTT_Helper::get_timezone());
+		}
+		return $this->_timezone;
+	}
+
+
+	/**
+	 * This returns the date formats set for the given field name and also ensures that
+	 * $this->_timezone property is set correctly.
+	 *
+	 * @param string $field_name The name of the field the formats are being retrieved for.
+	 * @param bool   $pretty     Whether to return the pretty formats (true) or not (false).
+	 * @return array formats in an array with the date format first, and the time format last.
+	 * @throws EE_Error   If the given field_name is not of the EE_Datetime_Field type.
+	 * @since 4.6.x
+	 */
+	public function get_formats_for($field_name, $pretty = false)
+	{
+		$field_settings = $this->field_settings_for($field_name);
+		// if not a valid EE_Datetime_Field then throw error
+		if (! $field_settings instanceof EE_Datetime_Field) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'The field sent into EEM_Base::get_formats_for (%s) is not registered as a EE_Datetime_Field. Please check the spelling and make sure you are submitting the right field name to retrieve date_formats for.',
+						'event_espresso'
+					),
+					$field_name
+				)
+			);
+		}
+		// while we are here, let's make sure the timezone internally in EEM_Base matches what is stored on
+		// the field.
+		$this->_timezone = $field_settings->get_timezone();
+		return [$field_settings->get_date_format($pretty), $field_settings->get_time_format($pretty)];
+	}
+
+
+	/**
+	 * This returns the current time in a format setup for a query on this model.
+	 * Usage of this method makes it easier to setup queries against EE_Datetime_Field columns because
+	 * it will return:
+	 *  - a formatted string in the timezone and format currently set on the EE_Datetime_Field for the given field for
+	 *  NOW
+	 *  - or a unix timestamp (equivalent to time())
+	 * Note: When requesting a formatted string, if the date or time format doesn't include seconds, for example,
+	 * the time returned, because it uses that format, will also NOT include seconds. For this reason, if you want
+	 * the time returned to be the current time down to the exact second, set $timestamp to true.
+	 *
+	 * @param string $field_name       The field the current time is needed for.
+	 * @param bool   $timestamp        True means to return a unix timestamp. Otherwise a
+	 *                                 formatted string matching the set format for the field in the set timezone will
+	 *                                 be returned.
+	 * @param string $what             Whether to return the string in just the time format, the date format, or both.
+	 * @return int|string  If the given field_name is not of the EE_Datetime_Field type, then an EE_Error
+	 *                                 exception is triggered.
+	 * @throws EE_Error    If the given field_name is not of the EE_Datetime_Field type.
+	 * @throws Exception
+	 * @since 4.6.x
+	 */
+	public function current_time_for_query($field_name, $timestamp = false, $what = 'both')
+	{
+		$formats  = $this->get_formats_for($field_name);
+		$DateTime = new DateTime("now", new DateTimeZone($this->_timezone));
+		if ($timestamp) {
+			return $DateTime->format('U');
+		}
+		// not returning timestamp, so return formatted string in timezone.
+		switch ($what) {
+			case 'time':
+				return $DateTime->format($formats[1]);
+			case 'date':
+				return $DateTime->format($formats[0]);
+			default:
+				return $DateTime->format(implode(' ', $formats));
+		}
+	}
+
+
+	/**
+	 * This receives a time string for a given field and ensures that it is setup to match what the internal settings
+	 * for the model are.  Returns a DateTime object.
+	 * Note: a gotcha for when you send in unix timestamp.  Remember a unix timestamp is already timezone agnostic,
+	 * (functionally the equivalent of UTC+0).  So when you send it in, whatever timezone string you include is
+	 * ignored.
+	 *
+	 * @param string $field_name      The field being setup.
+	 * @param string $timestring      The date time string being used.
+	 * @param string $incoming_format The format for the time string.
+	 * @param string $timezone        By default, it is assumed the incoming time string is in timezone for
+	 *                                the blog.  If this is not the case, then it can be specified here.  If incoming
+	 *                                format is
+	 *                                'U', this is ignored.
+	 * @return DateTime
+	 * @throws EE_Error
+	 */
+	public function convert_datetime_for_query($field_name, $timestring, $incoming_format, $timezone = '')
+	{
+		// just using this to ensure the timezone is set correctly internally
+		$this->get_formats_for($field_name);
+		// load EEH_DTT_Helper
+		$set_timezone     = empty($timezone) ? EEH_DTT_Helper::get_timezone() : $timezone;
+		$incomingDateTime = date_create_from_format($incoming_format, $timestring, new DateTimeZone($set_timezone));
+		EEH_DTT_Helper::setTimezone($incomingDateTime, new DateTimeZone($this->_timezone));
+		return \EventEspresso\core\domain\entities\DbSafeDateTime::createFromDateTime($incomingDateTime);
+	}
+
+
+	/**
+	 * Gets all the tables comprising this model. Array keys are the table aliases, and values are EE_Table objects
+	 *
+	 * @return EE_Table_Base[]
+	 */
+	public function get_tables()
+	{
+		return $this->_tables;
+	}
+
+
+	/**
+	 * Updates all the database entries (in each table for this model) according to $fields_n_values and optionally
+	 * also updates all the model objects, where the criteria expressed in $query_params are met..
+	 * Also note: if this model has multiple tables, this update verifies all the secondary tables have an entry for
+	 * each row (in the primary table) we're trying to update; if not, it inserts an entry in the secondary table. Eg:
+	 * if our model has 2 tables: wp_posts (primary), and wp_esp_event (secondary). Let's say we are trying to update a
+	 * model object with EVT_ID = 1
+	 * (which means where wp_posts has ID = 1, because wp_posts.ID is the primary key's column), which exists, but
+	 * there is no entry in wp_esp_event for this entry in wp_posts. So, this update script will insert a row into
+	 * wp_esp_event, using any available parameters from $fields_n_values (eg, if "EVT_limit" => 40 is in
+	 * $fields_n_values, the new entry in wp_esp_event will set EVT_limit = 40, and use default for other columns which
+	 * are not specified)
+	 *
+	 * @param array   $fields_n_values         keys are model fields (exactly like keys in EEM_Base::_fields, NOT db
+	 *                                         columns!), values are strings, ints, floats, and maybe arrays if they
+	 *                                         are to be serialized. Basically, the values are what you'd expect to be
+	 *                                         values on the model, NOT necessarily what's in the DB. For example, if
+	 *                                         we wanted to update only the TXN_details on any Transactions where its
+	 *                                         ID=34, we'd use this method as follows:
+	 *                                         EEM_Transaction::instance()->update(
+	 *                                         array('TXN_details'=>array('detail1'=>'monkey','detail2'=>'banana'),
+	 *                                         array(array('TXN_ID'=>34)));
+	 * @param array   $query_params            @see
+	 *                                         https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 *                                         Eg, consider updating Question's QST_admin_label field is of type
+	 *                                         Simple_HTML. If you use this function to update that field to $new_value
+	 *                                         = (note replace 8's with appropriate opening and closing tags in the
+	 *                                         following example)"8script8alert('I hack all');8/script88b8boom
+	 *                                         baby8/b8", then if you set $values_already_prepared_by_model_object to
+	 *                                         TRUE, it is assumed that you've already called
+	 *                                         EE_Simple_HTML_Field->prepare_for_set($new_value), which removes the
+	 *                                         malicious javascript. However, if
+	 *                                         $values_already_prepared_by_model_object is left as FALSE, then
+	 *                                         EE_Simple_HTML_Field->prepare_for_set($new_value) will be called on it,
+	 *                                         and every other field, before insertion. We provide this parameter
+	 *                                         because model objects perform their prepare_for_set function on all
+	 *                                         their values, and so don't need to be called again (and in many cases,
+	 *                                         shouldn't be called again. Eg: if we escape HTML characters in the
+	 *                                         prepare_for_set method...)
+	 * @param boolean $keep_model_objs_in_sync if TRUE, makes sure we ALSO update model objects
+	 *                                         in this model's entity map according to $fields_n_values that match
+	 *                                         $query_params. This obviously has some overhead, so you can disable it
+	 *                                         by setting this to FALSE, but be aware that model objects being used
+	 *                                         could get out-of-sync with the database
+	 * @return int how many rows got updated or FALSE if something went wrong with the query (wp returns FALSE or num
+	 *                                         rows affected which *could* include 0 which DOES NOT mean the query was
+	 *                                         bad)
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function update($fields_n_values, $query_params, $keep_model_objs_in_sync = true)
+	{
+		if (! is_array($query_params)) {
+			EE_Error::doing_it_wrong(
+				'EEM_Base::update',
+				sprintf(
+					esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
+					gettype($query_params)
+				),
+				'4.6.0'
+			);
+			$query_params = [];
+		}
+		/**
+		 * Action called before a model update call has been made.
+		 *
+		 * @param EEM_Base $model
+		 * @param array    $fields_n_values the updated fields and their new values
+		 * @param array    $query_params    @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+		 */
+		do_action('AHEE__EEM_Base__update__begin', $this, $fields_n_values, $query_params);
+		/**
+		 * Filters the fields about to be updated given the query parameters. You can provide the
+		 * $query_params to $this->get_all() to find exactly which records will be updated
+		 *
+		 * @param array    $fields_n_values fields and their new values
+		 * @param EEM_Base $model           the model being queried
+		 * @param array    $query_params    @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+		 */
+		$fields_n_values = (array) apply_filters(
+			'FHEE__EEM_Base__update__fields_n_values',
+			$fields_n_values,
+			$this,
+			$query_params
+		);
+		// need to verify that, for any entry we want to update, there are entries in each secondary table.
+		// to do that, for each table, verify that it's PK isn't null.
+		$tables = $this->get_tables();
+		// and if the other tables don't have a row for each table-to-be-updated, we'll insert one with whatever values available in the current update query
+		// NOTE: we should make this code more efficient by NOT querying twice
+		// before the real update, but that needs to first go through ALPHA testing
+		// as it's dangerous. says Mike August 8 2014
+		// we want to make sure the default_where strategy is ignored
+		$this->_ignore_where_strategy = true;
+		$wpdb_select_results          = $this->_get_all_wpdb_results($query_params);
+		foreach ($wpdb_select_results as $wpdb_result) {
+			// type cast stdClass as array
+			$wpdb_result = (array) $wpdb_result;
+			// get the model object's PK, as we'll want this if we need to insert a row into secondary tables
+			if ($this->has_primary_key_field()) {
+				$main_table_pk_value = $wpdb_result[ $this->get_primary_key_field()->get_qualified_column() ];
+			} else {
+				// if there's no primary key, we basically can't support having a 2nd table on the model (we could but it would be lots of work)
+				$main_table_pk_value = null;
+			}
+			// if there are more than 1 tables, we'll want to verify that each table for this model has an entry in the other tables
+			// and if the other tables don't have a row for each table-to-be-updated, we'll insert one with whatever values available in the current update query
+			if (count($tables) > 1) {
+				// foreach matching row in the DB, ensure that each table's PK isn't null. If so, there must not be an entry
+				// in that table, and so we'll want to insert one
+				foreach ($tables as $table_obj) {
+					$this_table_pk_column = $table_obj->get_fully_qualified_pk_column();
+					// if there is no private key for this table on the results, it means there's no entry
+					// in this table, right? so insert a row in the current table, using any fields available
+					if (
+						! (array_key_exists($this_table_pk_column, $wpdb_result)
+						   && $wpdb_result[ $this_table_pk_column ])
+					) {
+						$success = $this->_insert_into_specific_table(
+							$table_obj,
+							$fields_n_values,
+							$main_table_pk_value
+						);
+						// if we died here, report the error
+						if (! $success) {
+							return false;
+						}
+					}
+				}
+			}
+			//              //and now check that if we have cached any models by that ID on the model, that
+			//              //they also get updated properly
+			//              $model_object = $this->get_from_entity_map( $main_table_pk_value );
+			//              if( $model_object ){
+			//                  foreach( $fields_n_values as $field => $value ){
+			//                      $model_object->set($field, $value);
+			// let's make sure default_where strategy is followed now
+			$this->_ignore_where_strategy = false;
+		}
+		// if we want to keep model objects in sync, AND
+		// if this wasn't called from a model object (to update itself)
+		// then we want to make sure we keep all the existing
+		// model objects in sync with the db
+		if ($keep_model_objs_in_sync && ! $this->_values_already_prepared_by_model_object) {
+			if ($this->has_primary_key_field()) {
+				$model_objs_affected_ids = $this->get_col($query_params);
+			} else {
+				// we need to select a bunch of columns and then combine them into the the "index primary key string"s
+				$models_affected_key_columns = $this->_get_all_wpdb_results($query_params, ARRAY_A);
+				$model_objs_affected_ids     = [];
+				foreach ($models_affected_key_columns as $row) {
+					$combined_index_key                             = $this->get_index_primary_key_string($row);
+					$model_objs_affected_ids[ $combined_index_key ] = $combined_index_key;
+				}
+			}
+			if (! $model_objs_affected_ids) {
+				// wait wait wait- if nothing was affected let's stop here
+				return 0;
+			}
+			foreach ($model_objs_affected_ids as $id) {
+				$model_obj_in_entity_map = $this->get_from_entity_map($id);
+				if ($model_obj_in_entity_map) {
+					foreach ($fields_n_values as $field => $new_value) {
+						$model_obj_in_entity_map->set($field, $new_value);
+					}
+				}
+			}
+			// if there is a primary key on this model, we can now do a slight optimization
+			if ($this->has_primary_key_field()) {
+				// we already know what we want to update. So let's make the query simpler so it's a little more efficient
+				$query_params = [
+					[$this->primary_key_name() => ['IN', $model_objs_affected_ids]],
+					'limit'                    => count($model_objs_affected_ids),
+					'default_where_conditions' => EEM_Base::default_where_conditions_none,
+				];
+			}
+		}
+		$model_query_info = $this->_create_model_query_info_carrier($query_params);
+		$SQL              = "UPDATE "
+							. $model_query_info->get_full_join_sql()
+							. " SET "
+							. $this->_construct_update_sql($fields_n_values)
+							. $model_query_info->get_where_sql(
+							);// note: doesn't use _construct_2nd_half_of_select_query() because doesn't accept LIMIT, ORDER BY, etc.
+		$rows_affected    = $this->_do_wpdb_query('query', [$SQL]);
+		/**
+		 * Action called after a model update call has been made.
+		 *
+		 * @param EEM_Base $model
+		 * @param array    $fields_n_values the updated fields and their new values
+		 * @param array    $query_params    @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+		 * @param int      $rows_affected
+		 */
+		do_action('AHEE__EEM_Base__update__end', $this, $fields_n_values, $query_params, $rows_affected);
+		return $rows_affected;// how many supposedly got updated
+	}
+
+
+	/**
+	 * Analogous to $wpdb->get_col, returns a 1-dimensional array where teh values
+	 * are teh values of the field specified (or by default the primary key field)
+	 * that matched the query params. Note that you should pass the name of the
+	 * model FIELD, not the database table's column name.
+	 *
+	 * @param array  $query_params @see
+	 *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_select
+	 * @return array just like $wpdb->get_col()
+	 * @throws EE_Error
+	 */
+	public function get_col($query_params = [], $field_to_select = null)
+	{
+		if ($field_to_select) {
+			$field = $this->field_settings_for($field_to_select);
+		} elseif ($this->has_primary_key_field()) {
+			$field = $this->get_primary_key_field();
+		} else {
+			$field_settings = $this->field_settings();
+			// no primary key, just grab the first column
+			$field = reset($field_settings);
+			// don't need this array now
+			unset($field_settings);
+		}
+		$model_query_info   = $this->_create_model_query_info_carrier($query_params);
+		$select_expressions = $field->get_qualified_column();
+		$SQL                =
+			"SELECT $select_expressions " . $this->_construct_2nd_half_of_select_query($model_query_info);
+		return $this->_do_wpdb_query('get_col', [$SQL]);
+	}
+
+
+	/**
+	 * Returns a single column value for a single row from the database
+	 *
+	 * @param array  $query_params    @see
+	 *                                https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_select @see EEM_Base::get_col()
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function get_var($query_params = [], $field_to_select = null)
+	{
+		$query_params['limit'] = 1;
+		$col                   = $this->get_col($query_params, $field_to_select);
+		if (! empty($col)) {
+			return reset($col);
+		}
+		return null;
+	}
+
+
+	/**
+	 * Makes the SQL for after "UPDATE table_X inner join table_Y..." and before "...WHERE". Eg "Question.name='party
+	 * time?', Question.desc='what do you think?',..." Values are filtered through wpdb->prepare to avoid against SQL
+	 * injection, but currently no further filtering is done
+	 *
+	 * @param array $fields_n_values array keys are field names on this model, and values are what those fields should
+	 *                               be updated to in the DB
+	 * @return string of SQL
+	 * @throws EE_Error
+	 * @global      $wpdb
+	 */
+	public function _construct_update_sql($fields_n_values)
+	{
+		/** @type WPDB $wpdb */
+		global $wpdb;
+		$cols_n_values = [];
+		foreach ($fields_n_values as $field_name => $value) {
+			$field_obj = $this->field_settings_for($field_name);
+			// if the value is NULL, we want to assign the value to that.
+			// wpdb->prepare doesn't really handle that properly
+			$prepared_value  = $this->_prepare_value_or_use_default($field_obj, $fields_n_values);
+			$value_sql       = $prepared_value === null ? 'NULL'
+				: $wpdb->prepare($field_obj->get_wpdb_data_type(), $prepared_value);
+			$cols_n_values[] = $field_obj->get_qualified_column() . "=" . $value_sql;
+		}
+		return implode(",", $cols_n_values);
+	}
+
+
+	/**
+	 * Deletes a single row from the DB given the model object's primary key value. (eg, EE_Attendee->ID()'s value).
+	 * Performs a HARD delete, meaning the database row should always be removed,
+	 * not just have a flag field on it switched
+	 * Wrapper for EEM_Base::delete_permanently()
+	 *
+	 * @param mixed   $id
+	 * @param boolean $allow_blocking
+	 * @return int the number of rows deleted
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function delete_permanently_by_ID($id, $allow_blocking = true)
+	{
+		return $this->delete_permanently(
+			[
+				[$this->get_primary_key_field()->get_name() => $id],
+				'limit' => 1,
+			],
+			$allow_blocking
+		);
+	}
+
+
+	/**
+	 * Deletes a single row from the DB given the model object's primary key value. (eg, EE_Attendee->ID()'s value).
+	 * Wrapper for EEM_Base::delete()
+	 *
+	 * @param mixed   $id
+	 * @param boolean $allow_blocking
+	 * @return int the number of rows deleted
+	 * @throws EE_Error
+	 */
+	public function delete_by_ID($id, $allow_blocking = true)
+	{
+		return $this->delete(
+			[
+				[$this->get_primary_key_field()->get_name() => $id],
+				'limit' => 1,
+			],
+			$allow_blocking
+		);
+	}
+
+
+	/**
+	 * Identical to delete_permanently, but does a "soft" delete if possible,
+	 * meaning if the model has a field that indicates its been "trashed" or
+	 * "soft deleted", we will just set that instead of actually deleting the rows.
+	 *
+	 * @param array   $query_params
+	 * @param boolean $allow_blocking
+	 * @return int how many rows got deleted
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see EEM_Base::delete_permanently
+	 */
+	public function delete($query_params, $allow_blocking = true)
+	{
+		return $this->delete_permanently($query_params, $allow_blocking);
+	}
+
+
+	/**
+	 * Deletes the model objects that meet the query params. Note: this method is overridden
+	 * in EEM_Soft_Delete_Base so that soft-deleted model objects are instead only flagged
+	 * as archived, not actually deleted
+	 *
+	 * @param array   $query_params   @see
+	 *                                https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param boolean $allow_blocking if TRUE, matched objects will only be deleted if there is no related model info
+	 *                                that blocks it (ie, there' sno other data that depends on this data); if false,
+	 *                                deletes regardless of other objects which may depend on it. Its generally
+	 *                                advisable to always leave this as TRUE, otherwise you could easily corrupt your
+	 *                                DB
+	 * @return int how many rows got deleted
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function delete_permanently($query_params, $allow_blocking = true)
+	{
+		/**
+		 * Action called just before performing a real deletion query. You can use the
+		 * model and its $query_params to find exactly which items will be deleted
+		 *
+		 * @param EEM_Base $model
+		 * @param array    $query_params   @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+		 * @param boolean  $allow_blocking whether or not to allow related model objects
+		 *                                 to block (prevent) this deletion
+		 */
+		do_action('AHEE__EEM_Base__delete__begin', $this, $query_params, $allow_blocking);
+		// some MySQL databases may be running safe mode, which may restrict
+		// deletion if there is no KEY column used in the WHERE statement of a deletion.
+		// to get around this, we first do a SELECT, get all the IDs, and then run another query
+		// to delete them
+		$items_for_deletion           = $this->_get_all_wpdb_results($query_params);
+		$columns_and_ids_for_deleting = $this->_get_ids_for_delete($items_for_deletion, $allow_blocking);
+		$deletion_where_query_part    = $this->_build_query_part_for_deleting_from_columns_and_values(
+			$columns_and_ids_for_deleting
+		);
+		/**
+		 * Allows client code to act on the items being deleted before the query is actually executed.
+		 *
+		 * @param EEM_Base $this                            The model instance being acted on.
+		 * @param array    $query_params                    The incoming array of query parameters influencing what gets deleted.
+		 * @param bool     $allow_blocking                  @see param description in method phpdoc block.
+		 * @param array    $columns_and_ids_for_deleting    An array indicating what entities will get removed as
+		 *                                                  derived from the incoming query parameters.
+		 * @see details on the structure of this array in the phpdocs
+		 *                                                  for the `_get_ids_for_delete_method`
+		 *
+		 */
+		do_action(
+			'AHEE__EEM_Base__delete__before_query',
+			$this,
+			$query_params,
+			$allow_blocking,
+			$columns_and_ids_for_deleting
+		);
+		if ($deletion_where_query_part) {
+			$model_query_info = $this->_create_model_query_info_carrier($query_params);
+			$table_aliases    = array_keys($this->_tables);
+			$SQL              = "DELETE "
+								. implode(", ", $table_aliases)
+								. " FROM "
+								. $model_query_info->get_full_join_sql()
+								. " WHERE "
+								. $deletion_where_query_part;
+			$rows_deleted     = $this->_do_wpdb_query('query', [$SQL]);
+		} else {
+			$rows_deleted = 0;
+		}
+
+		// Next, make sure those items are removed from the entity map; if they could be put into it at all; and if
+		// there was no error with the delete query.
+		if (
+			$this->has_primary_key_field()
+			&& $rows_deleted !== false
+			&& isset($columns_and_ids_for_deleting[ $this->get_primary_key_field()->get_qualified_column() ])
+		) {
+			$ids_for_removal = $columns_and_ids_for_deleting[ $this->get_primary_key_field()->get_qualified_column() ];
+			foreach ($ids_for_removal as $id) {
+				if (isset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ])) {
+					unset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ]);
+				}
+			}
+
+			// delete any extra meta attached to the deleted entities but ONLY if this model is not an instance of
+			// `EEM_Extra_Meta`.  In other words we want to prevent recursion on EEM_Extra_Meta::delete_permanently calls
+			// unnecessarily.  It's very unlikely that users will have assigned Extra Meta to Extra Meta
+			// (although it is possible).
+			// Note this can be skipped by using the provided filter and returning false.
+			if (
+				apply_filters(
+					'FHEE__EEM_Base__delete_permanently__dont_delete_extra_meta_for_extra_meta',
+					! $this instanceof EEM_Extra_Meta,
+					$this
+				)
+			) {
+				EEM_Extra_Meta::instance()->delete_permanently([
+																   0 => [
+																	   'EXM_type' => $this->get_this_model_name(),
+																	   'OBJ_ID'   => [
+																		   'IN',
+																		   $ids_for_removal,
+																	   ],
+																   ],
+															   ]);
+			}
+		}
+
+		/**
+		 * Action called just after performing a real deletion query. Although at this point the
+		 * items should have been deleted
+		 *
+		 * @param EEM_Base $model
+		 * @param array    $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+		 * @param int      $rows_deleted
+		 */
+		do_action('AHEE__EEM_Base__delete__end', $this, $query_params, $rows_deleted, $columns_and_ids_for_deleting);
+		return $rows_deleted;// how many supposedly got deleted
+	}
+
+
+	/**
+	 * Checks all the relations that throw error messages when there are blocking related objects
+	 * for related model objects. If there are any related model objects on those relations,
+	 * adds an EE_Error, and return true
+	 *
+	 * @param EE_Base_Class|int $this_model_obj_or_id
+	 * @param EE_Base_Class     $ignore_this_model_obj a model object like 'EE_Event', or 'EE_Term_Taxonomy', which
+	 *                                                 should be ignored when determining whether there are related
+	 *                                                 model objects which block this model object's deletion. Useful
+	 *                                                 if you know A is related to B and are considering deleting A,
+	 *                                                 but want to see if A has any other objects blocking its deletion
+	 *                                                 before removing the relation between A and B
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function delete_is_blocked_by_related_models($this_model_obj_or_id, $ignore_this_model_obj = null)
+	{
+		// first, if $ignore_this_model_obj was supplied, get its model
+		if ($ignore_this_model_obj && $ignore_this_model_obj instanceof EE_Base_Class) {
+			$ignored_model = $ignore_this_model_obj->get_model();
+		} else {
+			$ignored_model = null;
+		}
+		// now check all the relations of $this_model_obj_or_id and see if there
+		// are any related model objects blocking it?
+		$is_blocked = false;
+		foreach ($this->_model_relations as $relation_name => $relation_obj) {
+			if ($relation_obj->block_delete_if_related_models_exist()) {
+				// if $ignore_this_model_obj was supplied, then for the query
+				// on that model needs to be told to ignore $ignore_this_model_obj
+				if ($ignored_model && $relation_name === $ignored_model->get_this_model_name()) {
+					$related_model_objects = $relation_obj->get_all_related($this_model_obj_or_id, [
+						[
+							$ignored_model->get_primary_key_field()->get_name() => [
+								'!=',
+								$ignore_this_model_obj->ID(),
+							],
+						],
+					]);
+				} else {
+					$related_model_objects = $relation_obj->get_all_related($this_model_obj_or_id);
+				}
+				if ($related_model_objects) {
+					EE_Error::add_error($relation_obj->get_deletion_error_message(), __FILE__, __FUNCTION__, __LINE__);
+					$is_blocked = true;
+				}
+			}
+		}
+		return $is_blocked;
+	}
+
+
+	/**
+	 * Builds the columns and values for items to delete from the incoming $row_results_for_deleting array.
+	 *
+	 * @param array $row_results_for_deleting
+	 * @param bool  $allow_blocking
+	 * @return array   The shape of this array depends on whether the model `has_primary_key_field` or not.  If the
+	 *                              model DOES have a primary_key_field, then the array will be a simple single
+	 *                              dimension array where the key is the fully qualified primary key column and the
+	 *                              value is an array of ids that will be deleted. Example: array('Event.EVT_ID' =>
+	 *                              array( 1,2,3)) If the model DOES NOT have a primary_key_field, then the array will
+	 *                              be a two dimensional array where each element is a group of columns and values that
+	 *                              get deleted. Example: array(
+	 *                              0 => array(
+	 *                              'Term_Relationship.object_id' => 1
+	 *                              'Term_Relationship.term_taxonomy_id' => 5
+	 *                              ),
+	 *                              1 => array(
+	 *                              'Term_Relationship.object_id' => 1
+	 *                              'Term_Relationship.term_taxonomy_id' => 6
+	 *                              )
+	 *                              )
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _get_ids_for_delete(array $row_results_for_deleting, $allow_blocking = true)
+	{
+		$ids_to_delete_indexed_by_column = [];
+		if ($this->has_primary_key_field()) {
+			$primary_table                   = $this->_get_main_table();
+			$primary_table_pk_field          =
+				$this->get_field_by_column($primary_table->get_fully_qualified_pk_column());
+			$other_tables                    = $this->_get_other_tables();
+			$ids_to_delete_indexed_by_column = $query = [];
+			foreach ($row_results_for_deleting as $item_to_delete) {
+				// before we mark this item for deletion,
+				// make sure there's no related entities blocking its deletion (if we're checking)
+				if (
+					$allow_blocking
+					&& $this->delete_is_blocked_by_related_models(
+						$item_to_delete[ $primary_table->get_fully_qualified_pk_column() ]
+					)
+				) {
+					continue;
+				}
+				// primary table deletes
+				if (isset($item_to_delete[ $primary_table->get_fully_qualified_pk_column() ])) {
+					$ids_to_delete_indexed_by_column[ $primary_table->get_fully_qualified_pk_column() ][] =
+						$item_to_delete[ $primary_table->get_fully_qualified_pk_column() ];
+				}
+			}
+		} elseif (count($this->get_combined_primary_key_fields()) > 1) {
+			$fields = $this->get_combined_primary_key_fields();
+			foreach ($row_results_for_deleting as $item_to_delete) {
+				$ids_to_delete_indexed_by_column_for_row = [];
+				foreach ($fields as $cpk_field) {
+					if ($cpk_field instanceof EE_Model_Field_Base) {
+						$ids_to_delete_indexed_by_column_for_row[ $cpk_field->get_qualified_column() ] =
+							$item_to_delete[ $cpk_field->get_qualified_column() ];
+					}
+				}
+				$ids_to_delete_indexed_by_column[] = $ids_to_delete_indexed_by_column_for_row;
+			}
+		} else {
+			// so there's no primary key and no combined key...
+			// sorry, can't help you
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"Cannot delete objects of type %s because there is no primary key NOR combined key",
+						"event_espresso"
+					),
+					get_class($this)
+				)
+			);
+		}
+		return $ids_to_delete_indexed_by_column;
+	}
+
+
+	/**
+	 * This receives an array of columns and values set to be deleted (as prepared by _get_ids_for_delete) and prepares
+	 * the corresponding query_part for the query performing the delete.
+	 *
+	 * @param array $ids_to_delete_indexed_by_column @see _get_ids_for_delete for how this array might be shaped.
+	 * @return string
+	 * @throws EE_Error
+	 */
+	protected function _build_query_part_for_deleting_from_columns_and_values(array $ids_to_delete_indexed_by_column)
+	{
+		$query_part = '';
+		if (empty($ids_to_delete_indexed_by_column)) {
+			return $query_part;
+		} elseif ($this->has_primary_key_field()) {
+			$query = [];
+			foreach ($ids_to_delete_indexed_by_column as $column => $ids) {
+				$query[] = $column . ' IN' . $this->_construct_in_value($ids, $this->_primary_key_field);
+			}
+			$query_part = ! empty($query) ? implode(' AND ', $query) : $query_part;
+		} elseif (count($this->get_combined_primary_key_fields()) > 1) {
+			$ways_to_identify_a_row = [];
+			foreach ($ids_to_delete_indexed_by_column as $ids_to_delete_indexed_by_column_for_each_row) {
+				$values_for_each_combined_primary_key_for_a_row = [];
+				foreach ($ids_to_delete_indexed_by_column_for_each_row as $column => $id) {
+					$values_for_each_combined_primary_key_for_a_row[] = $column . '=' . $id;
+				}
+				$ways_to_identify_a_row[] = '('
+											. implode(' AND ', $values_for_each_combined_primary_key_for_a_row)
+											. ')';
+			}
+			$query_part = implode(' OR ', $ways_to_identify_a_row);
+		}
+		return $query_part;
+	}
+
+
+	/**
+	 * Gets the model field by the fully qualified name
+	 *
+	 * @param string $qualified_column_name eg 'Event_CPT.post_name' or $field_obj->get_qualified_column()
+	 * @return EE_Model_Field_Base
+	 * @throws EE_Error
+	 * @throws EE_Error
+	 */
+	public function get_field_by_column($qualified_column_name)
+	{
+		foreach ($this->field_settings(true) as $field_name => $field_obj) {
+			if ($field_obj->get_qualified_column() === $qualified_column_name) {
+				return $field_obj;
+			}
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__('Could not find a field on the model "%1$s" for qualified column "%2$s"', 'event_espresso'),
+				$this->get_this_model_name(),
+				$qualified_column_name
+			)
+		);
+	}
+
+
+	/**
+	 * Count all the rows that match criteria the model query params.
+	 * If $field_to_count isn't provided, the model's primary key is used. Otherwise, we count by field_to_count's
+	 * column
+	 *
+	 * @param array  $query_params   @see
+	 *                               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_count field on model to count by (not column name)
+	 * @param bool   $distinct       if we want to only count the distinct values for the column then you can trigger
+	 *                               that by the setting $distinct to TRUE;
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function count($query_params = [], $field_to_count = null, $distinct = false)
+	{
+		$model_query_info = $this->_create_model_query_info_carrier($query_params);
+		if ($field_to_count) {
+			$field_obj       = $this->field_settings_for($field_to_count);
+			$column_to_count = $field_obj->get_qualified_column();
+		} elseif ($this->has_primary_key_field()) {
+			$pk_field_obj    = $this->get_primary_key_field();
+			$column_to_count = $pk_field_obj->get_qualified_column();
+		} else {
+			// there's no primary key
+			// if we're counting distinct items, and there's no primary key,
+			// we need to list out the columns for distinction;
+			// otherwise we can just use star
+			if ($distinct) {
+				$columns_to_use = [];
+				foreach ($this->get_combined_primary_key_fields() as $field_obj) {
+					$columns_to_use[] = $field_obj->get_qualified_column();
+				}
+				$column_to_count = implode(',', $columns_to_use);
+			} else {
+				$column_to_count = '*';
+			}
+		}
+		$column_to_count = $distinct ? "DISTINCT " . $column_to_count : $column_to_count;
+		$SQL             =
+			"SELECT COUNT(" . $column_to_count . ")" . $this->_construct_2nd_half_of_select_query($model_query_info);
+		return (int) $this->_do_wpdb_query('get_var', [$SQL]);
+	}
+
+
+	/**
+	 * Sums up the value of the $field_to_sum (defaults to the primary key, which isn't terribly useful)
+	 *
+	 * @param array  $query_params @see
+	 *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_sum name of field (array key in $_fields array)
+	 * @return float
+	 * @throws EE_Error
+	 */
+	public function sum($query_params, $field_to_sum = null)
+	{
+		$model_query_info = $this->_create_model_query_info_carrier($query_params);
+		if ($field_to_sum) {
+			$field_obj = $this->field_settings_for($field_to_sum);
+		} else {
+			$field_obj = $this->get_primary_key_field();
+		}
+		$column_to_count = $field_obj->get_qualified_column();
+		$SQL             =
+			"SELECT SUM(" . $column_to_count . ")" . $this->_construct_2nd_half_of_select_query($model_query_info);
+		$return_value    = $this->_do_wpdb_query('get_var', [$SQL]);
+		$data_type       = $field_obj->get_wpdb_data_type();
+		if ($data_type === '%d' || $data_type === '%s') {
+			return (float) $return_value;
+		}
+		// must be %f
+		return (float) $return_value;
+	}
+
+
+	/**
+	 * Just calls the specified method on $wpdb with the given arguments
+	 * Consolidates a little extra error handling code
+	 *
+	 * @param string $wpdb_method
+	 * @param array  $arguments_to_provide
+	 * @return mixed
+	 * @throws EE_Error
+	 * @global wpdb  $wpdb
+	 */
+	protected function _do_wpdb_query($wpdb_method, $arguments_to_provide)
+	{
+		// if we're in maintenance mode level 2, DON'T run any queries
+		// because level 2 indicates the database needs updating and
+		// is probably out of sync with the code
+		if (! EE_Maintenance_Mode::instance()->models_can_query()) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"Event Espresso Level 2 Maintenance mode is active. That means EE can not run ANY database queries until the necessary migration scripts have run which will take EE out of maintenance mode level 2. Please inform support of this error.",
+						"event_espresso"
+					)
+				)
+			);
+		}
+		/** @type WPDB $wpdb */
+		global $wpdb;
+		if (! method_exists($wpdb, $wpdb_method)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'There is no method named "%s" on Wordpress\' $wpdb object',
+						'event_espresso'
+					),
+					$wpdb_method
+				)
+			);
+		}
+		if (WP_DEBUG) {
+			$old_show_errors_value = $wpdb->show_errors;
+			$wpdb->show_errors(false);
+		}
+		$result = $this->_process_wpdb_query($wpdb_method, $arguments_to_provide);
+		$this->show_db_query_if_previously_requested($wpdb->last_query);
+		if (WP_DEBUG) {
+			$wpdb->show_errors($old_show_errors_value);
+			if (! empty($wpdb->last_error)) {
+				throw new EE_Error(sprintf(esc_html__('WPDB Error: "%s"', 'event_espresso'), $wpdb->last_error));
+			}
+			if ($result === false) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'WPDB Error occurred, but no error message was logged by wpdb! The wpdb method called was "%1$s" and the arguments were "%2$s"',
+							'event_espresso'
+						),
+						$wpdb_method,
+						var_export($arguments_to_provide, true)
+					)
+				);
+			}
+		} elseif ($result === false) {
+			EE_Error::add_error(
+				sprintf(
+					esc_html__(
+						'A database error has occurred. Turn on WP_DEBUG for more information.||A database error occurred doing wpdb method "%1$s", with arguments "%2$s". The error was "%3$s"',
+						'event_espresso'
+					),
+					$wpdb_method,
+					var_export($arguments_to_provide, true),
+					$wpdb->last_error
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		}
+		return $result;
+	}
+
+
+	/**
+	 * Attempts to run the indicated WPDB method with the provided arguments,
+	 * and if there's an error tries to verify the DB is correct. Uses
+	 * the static property EEM_Base::$_db_verification_level to determine whether
+	 * we should try to fix the EE core db, the addons, or just give up
+	 *
+	 * @param string $wpdb_method
+	 * @param array  $arguments_to_provide
+	 * @return mixed
+	 */
+	private function _process_wpdb_query($wpdb_method, $arguments_to_provide)
+	{
+		/** @type WPDB $wpdb */
+		global $wpdb;
+		$wpdb->last_error = null;
+		$result           = call_user_func_array([$wpdb, $wpdb_method], $arguments_to_provide);
+		// was there an error running the query? but we don't care on new activations
+		// (we're going to setup the DB anyway on new activations)
+		if (
+			($result === false || ! empty($wpdb->last_error))
+			&& EE_System::instance()->detect_req_type() !== EE_System::req_type_new_activation
+		) {
+			switch (EEM_Base::$_db_verification_level) {
+				case EEM_Base::db_verified_none:
+					// let's double-check core's DB
+					$error_message = $this->_verify_core_db($wpdb_method, $arguments_to_provide);
+					break;
+				case EEM_Base::db_verified_core:
+					// STILL NO LOVE?? verify all the addons too. Maybe they need to be fixed
+					$error_message = $this->_verify_addons_db($wpdb_method, $arguments_to_provide);
+					break;
+				case EEM_Base::db_verified_addons:
+					// ummmm... you in trouble
+					return $result;
+			}
+			if (! empty($error_message)) {
+				EE_Log::instance()->log(__FILE__, __FUNCTION__, $error_message, 'error');
+				trigger_error($error_message);
+			}
+			return $this->_process_wpdb_query($wpdb_method, $arguments_to_provide);
+		}
+		return $result;
+	}
+
+
+	/**
+	 * Verifies the EE core database is up-to-date and records that we've done it on
+	 * EEM_Base::$_db_verification_level
+	 *
+	 * @param string $wpdb_method
+	 * @param array  $arguments_to_provide
+	 * @return string
+	 */
+	private function _verify_core_db($wpdb_method, $arguments_to_provide)
+	{
+		/** @type WPDB $wpdb */
+		global $wpdb;
+		// ok remember that we've already attempted fixing the core db, in case the problem persists
+		EEM_Base::$_db_verification_level = EEM_Base::db_verified_core;
+		$error_message                    = sprintf(
+			esc_html__(
+				'WPDB Error "%1$s" while running wpdb method "%2$s" with arguments %3$s. Automatically attempting to fix EE Core DB',
+				'event_espresso'
+			),
+			$wpdb->last_error,
+			$wpdb_method,
+			wp_json_encode($arguments_to_provide)
+		);
+		EE_System::instance()->initialize_db_if_no_migrations_required(false, true);
+		return $error_message;
+	}
+
+
+	/**
+	 * Verifies the EE addons' database is up-to-date and records that we've done it on
+	 * EEM_Base::$_db_verification_level
+	 *
+	 * @param $wpdb_method
+	 * @param $arguments_to_provide
+	 * @return string
+	 */
+	private function _verify_addons_db($wpdb_method, $arguments_to_provide)
+	{
+		/** @type WPDB $wpdb */
+		global $wpdb;
+		// ok remember that we've already attempted fixing the addons dbs, in case the problem persists
+		EEM_Base::$_db_verification_level = EEM_Base::db_verified_addons;
+		$error_message                    = sprintf(
+			esc_html__(
+				'WPDB AGAIN: Error "%1$s" while running the same method and arguments as before. Automatically attempting to fix EE Addons DB',
+				'event_espresso'
+			),
+			$wpdb->last_error,
+			$wpdb_method,
+			wp_json_encode($arguments_to_provide)
+		);
+		EE_System::instance()->initialize_addons();
+		return $error_message;
+	}
+
+
+	/**
+	 * In order to avoid repeating this code for the get_all, sum, and count functions, put the code parts
+	 * that are identical in here. Returns a string of SQL of everything in a SELECT query except the beginning
+	 * SELECT clause, eg " FROM wp_posts AS Event INNER JOIN ... WHERE ... ORDER BY ... LIMIT ... GROUP BY ... HAVING
+	 * ..."
+	 *
+	 * @param EE_Model_Query_Info_Carrier $model_query_info
+	 * @return string
+	 */
+	private function _construct_2nd_half_of_select_query(EE_Model_Query_Info_Carrier $model_query_info)
+	{
+		return " FROM " . $model_query_info->get_full_join_sql() .
+			   $model_query_info->get_where_sql() .
+			   $model_query_info->get_group_by_sql() .
+			   $model_query_info->get_having_sql() .
+			   $model_query_info->get_order_by_sql() .
+			   $model_query_info->get_limit_sql();
+	}
+
+
+	/**
+	 * Set to easily debug the next X queries ran from this model.
+	 *
+	 * @param int $count
+	 */
+	public function show_next_x_db_queries($count = 1)
+	{
+		$this->_show_next_x_db_queries = $count;
+	}
+
+
+	/**
+	 * @param $sql_query
+	 */
+	public function show_db_query_if_previously_requested($sql_query)
+	{
+		if ($this->_show_next_x_db_queries > 0) {
+			echo esc_html($sql_query);
+			$this->_show_next_x_db_queries--;
+		}
+	}
+
+
+	/**
+	 * Adds a relationship of the correct type between $modelObject and $otherModelObject.
+	 * There are the 3 cases:
+	 * 'belongsTo' relationship: sets $id_or_obj's foreign_key to be $other_model_id_or_obj's primary_key. If
+	 * $otherModelObject has no ID, it is first saved.
+	 * 'hasMany' relationship: sets $other_model_id_or_obj's foreign_key to be $id_or_obj's primary_key. If $id_or_obj
+	 * has no ID, it is first saved.
+	 * 'hasAndBelongsToMany' relationships: checks that there isn't already an entry in the join table, and adds one.
+	 * If one of the model Objects has not yet been saved to the database, it is saved before adding the entry in the
+	 * join table
+	 *
+	 * @param EE_Base_Class                     /int $thisModelObject
+	 * @param EE_Base_Class                     /int $id_or_obj EE_base_Class or ID of other Model Object
+	 * @param string $relationName                     , key in EEM_Base::_relations
+	 *                                                 an attendee to a group, you also want to specify which role they
+	 *                                                 will have in that group. So you would use this parameter to
+	 *                                                 specify array('role-column-name'=>'role-id')
+	 * @param array  $extra_join_model_fields_n_values This allows you to enter further query params for the relation
+	 *                                                 to for relation to methods that allow you to further specify
+	 *                                                 extra columns to join by (such as HABTM).  Keep in mind that the
+	 *                                                 only acceptable query_params is strict "col" => "value" pairs
+	 *                                                 because these will be inserted in any new rows created as well.
+	 * @return EE_Base_Class which was added as a relation. Object referred to by $other_model_id_or_obj
+	 * @throws EE_Error
+	 */
+	public function add_relationship_to(
+		$id_or_obj,
+		$other_model_id_or_obj,
+		$relationName,
+		$extra_join_model_fields_n_values = []
+	) {
+		$relation_obj = $this->related_settings_for($relationName);
+		return $relation_obj->add_relation_to($id_or_obj, $other_model_id_or_obj, $extra_join_model_fields_n_values);
+	}
+
+
+	/**
+	 * Removes a relationship of the correct type between $modelObject and $otherModelObject.
+	 * There are the 3 cases:
+	 * 'belongsTo' relationship: sets $modelObject's foreign_key to null, if that field is nullable.Otherwise throws an
+	 * error
+	 * 'hasMany' relationship: sets $otherModelObject's foreign_key to null,if that field is nullable.Otherwise throws
+	 * an error
+	 * 'hasAndBelongsToMany' relationships:removes any existing entry in the join table between the two models.
+	 *
+	 * @param EE_Base_Class /int $id_or_obj
+	 * @param EE_Base_Class /int $other_model_id_or_obj EE_Base_Class or ID of other Model Object
+	 * @param string $relationName key in EEM_Base::_relations
+	 * @param array  $where_query  This allows you to enter further query params for the relation to for relation to
+	 *                             methods that allow you to further specify extra columns to join by (such as HABTM).
+	 *                             Keep in mind that the only acceptable query_params is strict "col" => "value" pairs
+	 *                             because these will be inserted in any new rows created as well.
+	 * @return boolean of success
+	 * @throws EE_Error
+	 */
+	public function remove_relationship_to($id_or_obj, $other_model_id_or_obj, $relationName, $where_query = [])
+	{
+		$relation_obj = $this->related_settings_for($relationName);
+		return $relation_obj->remove_relation_to($id_or_obj, $other_model_id_or_obj, $where_query);
+	}
+
+
+	/**
+	 * @param mixed  $id_or_obj
+	 * @param string $relationName
+	 * @param array  $where_query_params
+	 * @param EE_Base_Class[] objects to which relations were removed
+	 * @return EE_Base_Class[]
+	 * @throws EE_Error
+	 */
+	public function remove_relations($id_or_obj, $relationName, $where_query_params = [])
+	{
+		$relation_obj = $this->related_settings_for($relationName);
+		return $relation_obj->remove_relations($id_or_obj, $where_query_params);
+	}
+
+
+	/**
+	 * Gets all the related items of the specified $model_name, using $query_params.
+	 * Note: by default, we remove the "default query params"
+	 * because we want to get even deleted items etc.
+	 *
+	 * @param mixed  $id_or_obj    EE_Base_Class child or its ID
+	 * @param string $model_name   like 'Event', 'Registration', etc. always singular
+	 * @param array  $query_params @see
+	 *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Base_Class[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_all_related($id_or_obj, $model_name, $query_params = null)
+	{
+		$model_obj         = $this->ensure_is_obj($id_or_obj);
+		$relation_settings = $this->related_settings_for($model_name);
+		return $relation_settings->get_all_related($model_obj, $query_params);
+	}
+
+
+	/**
+	 * Deletes all the model objects across the relation indicated by $model_name
+	 * which are related to $id_or_obj which meet the criteria set in $query_params.
+	 * However, if the model objects can't be deleted because of blocking related model objects, then
+	 * they aren't deleted. (Unless the thing that would have been deleted can be soft-deleted, that still happens).
+	 *
+	 * @param EE_Base_Class|int|string $id_or_obj
+	 * @param string                   $model_name
+	 * @param array                    $query_params
+	 * @return int how many deleted
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function delete_related($id_or_obj, $model_name, $query_params = [])
+	{
+		$model_obj         = $this->ensure_is_obj($id_or_obj);
+		$relation_settings = $this->related_settings_for($model_name);
+		return $relation_settings->delete_all_related($model_obj, $query_params);
+	}
+
+
+	/**
+	 * Hard deletes all the model objects across the relation indicated by $model_name
+	 * which are related to $id_or_obj which meet the criteria set in $query_params. If
+	 * the model objects can't be hard deleted because of blocking related model objects,
+	 * just does a soft-delete on them instead.
+	 *
+	 * @param EE_Base_Class|int|string $id_or_obj
+	 * @param string                   $model_name
+	 * @param array                    $query_params
+	 * @return int how many deleted
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function delete_related_permanently($id_or_obj, $model_name, $query_params = [])
+	{
+		$model_obj         = $this->ensure_is_obj($id_or_obj);
+		$relation_settings = $this->related_settings_for($model_name);
+		return $relation_settings->delete_related_permanently($model_obj, $query_params);
+	}
+
+
+	/**
+	 * Instead of getting the related model objects, simply counts them. Ignores default_where_conditions by default,
+	 * unless otherwise specified in the $query_params
+	 *
+	 * @param int             /EE_Base_Class $id_or_obj
+	 * @param string $model_name     like 'Event', or 'Registration'
+	 * @param array  $query_params   @see
+	 *                               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_count name of field to count by. By default, uses primary key
+	 * @param bool   $distinct       if we want to only count the distinct values for the column then you can trigger
+	 *                               that by the setting $distinct to TRUE;
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function count_related(
+		$id_or_obj,
+		$model_name,
+		$query_params = [],
+		$field_to_count = null,
+		$distinct = false
+	) {
+		$related_model = $this->get_related_model_obj($model_name);
+		// we're just going to use the query params on the related model's normal get_all query,
+		// except add a condition to say to match the current mod
+		if (! isset($query_params['default_where_conditions'])) {
+			$query_params['default_where_conditions'] = EEM_Base::default_where_conditions_none;
+		}
+		$this_model_name                                                 = $this->get_this_model_name();
+		$this_pk_field_name                                              = $this->get_primary_key_field()->get_name();
+		$query_params[0][ $this_model_name . "." . $this_pk_field_name ] = $id_or_obj;
+		return $related_model->count($query_params, $field_to_count, $distinct);
+	}
+
+
+	/**
+	 * Instead of getting the related model objects, simply sums up the values of the specified field.
+	 * Note: ignores default_where_conditions by default, unless otherwise specified in the $query_params
+	 *
+	 * @param int           /EE_Base_Class $id_or_obj
+	 * @param string $model_name   like 'Event', or 'Registration'
+	 * @param array  $query_params @see
+	 *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_sum name of field to count by. By default, uses primary key
+	 * @return float
+	 * @throws EE_Error
+	 */
+	public function sum_related($id_or_obj, $model_name, $query_params, $field_to_sum = null)
+	{
+		$related_model = $this->get_related_model_obj($model_name);
+		if (! is_array($query_params)) {
+			EE_Error::doing_it_wrong(
+				'EEM_Base::sum_related',
+				sprintf(
+					esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
+					gettype($query_params)
+				),
+				'4.6.0'
+			);
+			$query_params = [];
+		}
+		// we're just going to use the query params on the related model's normal get_all query,
+		// except add a condition to say to match the current mod
+		if (! isset($query_params['default_where_conditions'])) {
+			$query_params['default_where_conditions'] = EEM_Base::default_where_conditions_none;
+		}
+		$this_model_name                                                 = $this->get_this_model_name();
+		$this_pk_field_name                                              = $this->get_primary_key_field()->get_name();
+		$query_params[0][ $this_model_name . "." . $this_pk_field_name ] = $id_or_obj;
+		return $related_model->sum($query_params, $field_to_sum);
+	}
+
+
+	/**
+	 * Uses $this->_relatedModels info to find the first related model object of relation $relationName to the given
+	 * $modelObject
+	 *
+	 * @param int | EE_Base_Class $id_or_obj        EE_Base_Class child or its ID
+	 * @param string              $other_model_name , key in $this->_relatedModels, eg 'Registration', or 'Events'
+	 * @param array               $query_params     @see
+	 *                                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Base_Class
+	 * @throws EE_Error
+	 */
+	public function get_first_related(EE_Base_Class $id_or_obj, $other_model_name, $query_params)
+	{
+		$query_params['limit'] = 1;
+		$results               = $this->get_all_related($id_or_obj, $other_model_name, $query_params);
+		if ($results) {
+			return array_shift($results);
+		}
+		return null;
+	}
+
+
+	/**
+	 * Gets the model's name as it's expected in queries. For example, if this is EEM_Event model, that would be Event
+	 *
+	 * @return string
+	 */
+	public function get_this_model_name()
+	{
+		return str_replace("EEM_", "", get_class($this));
+	}
+
+
+	/**
+	 * Gets the model field on this model which is of type EE_Any_Foreign_Model_Name_Field
+	 *
+	 * @return EE_Any_Foreign_Model_Name_Field
+	 * @throws EE_Error
+	 */
+	public function get_field_containing_related_model_name()
+	{
+		foreach ($this->field_settings(true) as $field) {
+			if ($field instanceof EE_Any_Foreign_Model_Name_Field) {
+				$field_with_model_name = $field;
+			}
+		}
+		if (! isset($field_with_model_name) || ! $field_with_model_name) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__("There is no EE_Any_Foreign_Model_Name field on model %s", "event_espresso"),
+					$this->get_this_model_name()
+				)
+			);
+		}
+		return $field_with_model_name;
+	}
+
+
+	/**
+	 * Inserts a new entry into the database, for each table.
+	 * Note: does not add the item to the entity map because that is done by EE_Base_Class::save() right after this.
+	 * If client code uses EEM_Base::insert() directly, then although the item isn't in the entity map,
+	 * we also know there is no model object with the newly inserted item's ID at the moment (because
+	 * if there were, then they would already be in the DB and this would fail); and in the future if someone
+	 * creates a model object with this ID (or grabs it from the DB) then it will be added to the
+	 * entity map at that time anyways. SO, no need for EEM_Base::insert ot add to the entity map
+	 *
+	 * @param array $field_n_values keys are field names, values are their values (in the client code's domain if
+	 *                              $values_already_prepared_by_model_object is false, in the model object's domain if
+	 *                              $values_already_prepared_by_model_object is true. See comment about this at the top
+	 *                              of EEM_Base)
+	 * @return int|string new primary key on main table that got inserted
+	 * @throws EE_Error
+	 */
+	public function insert($field_n_values)
+	{
+		/**
+		 * Filters the fields and their values before inserting an item using the models
+		 *
+		 * @param array    $fields_n_values keys are the fields and values are their new values
+		 * @param EEM_Base $model           the model used
+		 */
+		$field_n_values = (array) apply_filters('FHEE__EEM_Base__insert__fields_n_values', $field_n_values, $this);
+		if ($this->_satisfies_unique_indexes($field_n_values)) {
+			$main_table = $this->_get_main_table();
+			$new_id     = $this->_insert_into_specific_table($main_table, $field_n_values, false);
+			if ($new_id !== false) {
+				foreach ($this->_get_other_tables() as $other_table) {
+					$this->_insert_into_specific_table($other_table, $field_n_values, $new_id);
+				}
+			}
+			/**
+			 * Done just after attempting to insert a new model object
+			 *
+			 * @param EEM_Base $model           used
+			 * @param array    $fields_n_values fields and their values
+			 * @param int|string the              ID of the newly-inserted model object
+			 */
+			do_action('AHEE__EEM_Base__insert__end', $this, $field_n_values, $new_id);
+			return $new_id;
+		}
+		return false;
+	}
+
+
+	/**
+	 * Checks that the result would satisfy the unique indexes on this model
+	 *
+	 * @param array  $field_n_values
+	 * @param string $action
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	protected function _satisfies_unique_indexes($field_n_values, $action = 'insert')
+	{
+		foreach ($this->unique_indexes() as $index_name => $index) {
+			$uniqueness_where_params = array_intersect_key($field_n_values, $index->fields());
+			if ($this->exists([$uniqueness_where_params])) {
+				EE_Error::add_error(
+					sprintf(
+						esc_html__(
+							"Could not %s %s. %s uniqueness index failed. Fields %s must form a unique set, but an entry already exists with values %s.",
+							"event_espresso"
+						),
+						$action,
+						$this->_get_class_name(),
+						$index_name,
+						implode(",", $index->field_names()),
+						http_build_query($uniqueness_where_params)
+					),
+					__FILE__,
+					__FUNCTION__,
+					__LINE__
+				);
+				return false;
+			}
+		}
+		return true;
+	}
+
+
+	/**
+	 * Checks the database for an item that conflicts (ie, if this item were
+	 * saved to the DB would break some uniqueness requirement, like a primary key
+	 * or an index primary key set) with the item specified. $id_obj_or_fields_array
+	 * can be either an EE_Base_Class or an array of fields n values
+	 *
+	 * @param EE_Base_Class|array $obj_or_fields_array
+	 * @param boolean             $include_primary_key whether to use the model object's primary key
+	 *                                                 when looking for conflicts
+	 *                                                 (ie, if false, we ignore the model object's primary key
+	 *                                                 when finding "conflicts". If true, it's also considered).
+	 *                                                 Only works for INT primary key,
+	 *                                                 STRING primary keys cannot be ignored
+	 * @return EE_Base_Class|array
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_one_conflicting($obj_or_fields_array, $include_primary_key = true)
+	{
+		if ($obj_or_fields_array instanceof EE_Base_Class) {
+			$fields_n_values = $obj_or_fields_array->model_field_array();
+		} elseif (is_array($obj_or_fields_array)) {
+			$fields_n_values = $obj_or_fields_array;
+		} else {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"%s get_all_conflicting should be called with a model object or an array of field names and values, you provided %d",
+						"event_espresso"
+					),
+					get_class($this),
+					$obj_or_fields_array
+				)
+			);
+		}
+		$query_params = [];
+		if (
+			$this->has_primary_key_field()
+			&& ($include_primary_key
+				|| $this->get_primary_key_field()
+				   instanceof
+				   EE_Primary_Key_String_Field)
+			&& isset($fields_n_values[ $this->primary_key_name() ])
+		) {
+			$query_params[0]['OR'][ $this->primary_key_name() ] = $fields_n_values[ $this->primary_key_name() ];
+		}
+		foreach ($this->unique_indexes() as $unique_index_name => $unique_index) {
+			$uniqueness_where_params                              =
+				array_intersect_key($fields_n_values, $unique_index->fields());
+			$query_params[0]['OR'][ 'AND*' . $unique_index_name ] = $uniqueness_where_params;
+		}
+		// if there is nothing to base this search on, then we shouldn't find anything
+		if (empty($query_params)) {
+			return [];
+		}
+		return $this->get_one($query_params);
+	}
+
+
+	/**
+	 * Like count, but is optimized and returns a boolean instead of an int
+	 *
+	 * @param array $query_params
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function exists($query_params)
+	{
+		$query_params['limit'] = 1;
+		return $this->count($query_params) > 0;
+	}
+
+
+	/**
+	 * Wrapper for exists, except ignores default query parameters so we're only considering ID
+	 *
+	 * @param int|string $id
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function exists_by_ID($id)
+	{
+		return $this->exists(
+			[
+				'default_where_conditions' => EEM_Base::default_where_conditions_none,
+				[
+					$this->primary_key_name() => $id,
+				],
+			]
+		);
+	}
+
+
+	/**
+	 * Inserts a new row in $table, using the $cols_n_values which apply to that table.
+	 * If a $new_id is supplied and if $table is an EE_Other_Table, we assume
+	 * we need to add a foreign key column to point to $new_id (which should be the primary key's value
+	 * on the main table)
+	 * This is protected rather than private because private is not accessible to any child methods and there MAY be
+	 * cases where we want to call it directly rather than via insert().
+	 *
+	 * @access   protected
+	 * @param EE_Table_Base $table
+	 * @param array         $fields_n_values each key should be in field's keys, and value should be an int, string or
+	 *                                       float
+	 * @param int           $new_id          for now we assume only int keys
+	 * @return int ID of new row inserted, or FALSE on failure
+	 * @throws EE_Error
+	 * @global WPDB         $wpdb            only used to get the $wpdb->insert_id after performing an insert
+	 */
+	protected function _insert_into_specific_table(EE_Table_Base $table, $fields_n_values, $new_id = 0)
+	{
+		global $wpdb;
+		$insertion_col_n_values = [];
+		$format_for_insertion   = [];
+		$fields_on_table        = $this->_get_fields_for_table($table->get_table_alias());
+		foreach ($fields_on_table as $field_name => $field_obj) {
+			// check if its an auto-incrementing column, in which case we should just leave it to do its autoincrement thing
+			if ($field_obj->is_auto_increment()) {
+				continue;
+			}
+			$prepared_value = $this->_prepare_value_or_use_default($field_obj, $fields_n_values);
+			// if the value we want to assign it to is NULL, just don't mention it for the insertion
+			if ($prepared_value !== null) {
+				$insertion_col_n_values[ $field_obj->get_table_column() ] = $prepared_value;
+				$format_for_insertion[]                                   = $field_obj->get_wpdb_data_type();
+			}
+		}
+		if ($table instanceof EE_Secondary_Table && $new_id) {
+			// its not the main table, so we should have already saved the main table's PK which we just inserted
+			// so add the fk to the main table as a column
+			$insertion_col_n_values[ $table->get_fk_on_table() ] = $new_id;
+			$format_for_insertion[]                              =
+				'%d';// yes right now we're only allowing these foreign keys to be INTs
+		}
+
+		// insert the new entry
+		$result = $this->_do_wpdb_query(
+			'insert',
+			[$table->get_table_name(), $insertion_col_n_values, $format_for_insertion]
+		);
+		if ($result === false) {
+			return false;
+		}
+		// ok, now what do we return for the ID of the newly-inserted thing?
+		if ($this->has_primary_key_field()) {
+			if ($this->get_primary_key_field()->is_auto_increment()) {
+				return $wpdb->insert_id;
+			}
+			// it's not an auto-increment primary key, so
+			// it must have been supplied
+			return $fields_n_values[ $this->get_primary_key_field()->get_name() ];
+		}
+		// we can't return a  primary key because there is none. instead return
+		// a unique string indicating this model
+		return $this->get_index_primary_key_string($fields_n_values);
+	}
+
+
+	/**
+	 * Prepare the $field_obj 's value in $fields_n_values for use in the database.
+	 * If the field doesn't allow NULL, try to use its default. (If it doesn't allow NULL,
+	 * and there is no default, we pass it along. WPDB will take care of it)
+	 *
+	 * @param EE_Model_Field_Base $field_obj
+	 * @param array               $fields_n_values
+	 * @return mixed string|int|float depending on what the table column will be expecting
+	 * @throws EE_Error
+	 */
+	protected function _prepare_value_or_use_default($field_obj, $fields_n_values)
+	{
+		$field_name = $field_obj->get_name();
+		// if this field doesn't allow nullable, don't allow it
+		if (! $field_obj->is_nullable() && ! isset($fields_n_values[ $field_name ])) {
+			$fields_n_values[ $field_name ] = $field_obj->get_default_value();
+		}
+		$unprepared_value = $fields_n_values[ $field_name ] ?? null;
+		return $this->_prepare_value_for_use_in_db($unprepared_value, $field_obj);
+	}
+
+
+	/**
+	 * Consolidates code for preparing  a value supplied to the model for use int eh db. Calls the field's
+	 * prepare_for_use_in_db method on the value, and depending on $value_already_prepare_by_model_obj, may also call
+	 * the field's prepare_for_set() method.
+	 *
+	 * @param mixed               $value value in the client code domain if $value_already_prepared_by_model_object is
+	 *                                   false, otherwise a value in the model object's domain (see lengthy comment at
+	 *                                   top of file)
+	 * @param EE_Model_Field_Base $field field which will be doing the preparing of the value. If null, we assume
+	 *                                   $value is a custom selection
+	 * @return mixed a value ready for use in the database for insertions, updating, or in a where clause
+	 */
+	private function _prepare_value_for_use_in_db($value, $field)
+	{
+		if ($field instanceof EE_Model_Field_Base) {
+			// phpcs:disable PSR2.ControlStructures.SwitchDeclaration.TerminatingComment
+			switch ($this->_values_already_prepared_by_model_object) {
+				/** @noinspection PhpMissingBreakStatementInspection */
+				case self::not_prepared_by_model_object:
+					$value = $field->prepare_for_set($value);
+				// purposefully left out "return"
+				// no break
+				case self::prepared_by_model_object:
+					/** @noinspection SuspiciousAssignmentsInspection */
+					$value = $field->prepare_for_use_in_db($value);
+				// no break
+				case self::prepared_for_use_in_db:
+					// leave the value alone
+			}
+			// phpcs:enable
+		}
+		return $value;
+	}
+
+
+	/**
+	 * Returns the main table on this model
+	 *
+	 * @return EE_Primary_Table
+	 * @throws EE_Error
+	 */
+	protected function _get_main_table()
+	{
+		foreach ($this->_tables as $table) {
+			if ($table instanceof EE_Primary_Table) {
+				return $table;
+			}
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					'There are no main tables on %s. They should be added to _tables array in the constructor',
+					'event_espresso'
+				),
+				get_class($this)
+			)
+		);
+	}
+
+
+	/**
+	 * table
+	 * returns EE_Primary_Table table name
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function table()
+	{
+		return $this->_get_main_table()->get_table_name();
+	}
+
+
+	/**
+	 * table
+	 * returns first EE_Secondary_Table table name
+	 *
+	 * @return string
+	 */
+	public function second_table()
+	{
+		// grab second table from tables array
+		$second_table = end($this->_tables);
+		return $second_table instanceof EE_Secondary_Table ? $second_table->get_table_name() : null;
+	}
+
+
+	/**
+	 * get_table_obj_by_alias
+	 * returns table name given it's alias
+	 *
+	 * @param string $table_alias
+	 * @return EE_Primary_Table | EE_Secondary_Table
+	 */
+	public function get_table_obj_by_alias($table_alias = '')
+	{
+		return isset($this->_tables[ $table_alias ]) ? $this->_tables[ $table_alias ] : null;
+	}
+
+
+	/**
+	 * Gets all the tables of type EE_Other_Table from EEM_CPT_Basel_Model::_tables
+	 *
+	 * @return EE_Secondary_Table[]
+	 */
+	protected function _get_other_tables()
+	{
+		$other_tables = [];
+		foreach ($this->_tables as $table_alias => $table) {
+			if ($table instanceof EE_Secondary_Table) {
+				$other_tables[ $table_alias ] = $table;
+			}
+		}
+		return $other_tables;
+	}
+
+
+	/**
+	 * Finds all the fields that correspond to the given table
+	 *
+	 * @param string $table_alias , array key in EEM_Base::_tables
+	 * @return EE_Model_Field_Base[]
+	 */
+	public function _get_fields_for_table($table_alias)
+	{
+		return $this->_fields[ $table_alias ];
+	}
+
+
+	/**
+	 * Recurses through all the where parameters, and finds all the related models we'll need
+	 * to complete this query. Eg, given where parameters like array('EVT_ID'=>3) from within Event model, we won't
+	 * need any related models. But if the array were array('Registrations.REG_ID'=>3), we'd need the related
+	 * Registration model. If it were array('Registrations.Transactions.Payments.PAY_ID'=>3), then we'd need the
+	 * related Registration, Transaction, and Payment models.
+	 *
+	 * @param array $query_params @see
+	 *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Model_Query_Info_Carrier
+	 * @throws EE_Error
+	 */
+	public function _extract_related_models_from_query($query_params)
+	{
+		$query_info_carrier = new EE_Model_Query_Info_Carrier();
+		if (array_key_exists(0, $query_params)) {
+			$this->_extract_related_models_from_sub_params_array_keys($query_params[0], $query_info_carrier, 0);
+		}
+		if (array_key_exists('group_by', $query_params)) {
+			if (is_array($query_params['group_by'])) {
+				$this->_extract_related_models_from_sub_params_array_values(
+					$query_params['group_by'],
+					$query_info_carrier,
+					'group_by'
+				);
+			} elseif (! empty($query_params['group_by'])) {
+				$this->_extract_related_model_info_from_query_param(
+					$query_params['group_by'],
+					$query_info_carrier,
+					'group_by'
+				);
+			}
+		}
+		if (array_key_exists('having', $query_params)) {
+			$this->_extract_related_models_from_sub_params_array_keys(
+				$query_params[0],
+				$query_info_carrier,
+				'having'
+			);
+		}
+		if (array_key_exists('order_by', $query_params)) {
+			if (is_array($query_params['order_by'])) {
+				$this->_extract_related_models_from_sub_params_array_keys(
+					$query_params['order_by'],
+					$query_info_carrier,
+					'order_by'
+				);
+			} elseif (! empty($query_params['order_by'])) {
+				$this->_extract_related_model_info_from_query_param(
+					$query_params['order_by'],
+					$query_info_carrier,
+					'order_by'
+				);
+			}
+		}
+		if (array_key_exists('force_join', $query_params)) {
+			$this->_extract_related_models_from_sub_params_array_values(
+				$query_params['force_join'],
+				$query_info_carrier,
+				'force_join'
+			);
+		}
+		$this->extractRelatedModelsFromCustomSelects($query_info_carrier);
+		return $query_info_carrier;
+	}
+
+
+	/**
+	 * For extracting related models from WHERE (0), HAVING (having), ORDER BY (order_by) or forced joins (force_join)
+	 *
+	 * @param array                       $sub_query_params @see
+	 *                                                      https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#-0-where-conditions
+	 * @param EE_Model_Query_Info_Carrier $model_query_info_carrier
+	 * @param string                      $query_param_type one of $this->_allowed_query_params
+	 * @return EE_Model_Query_Info_Carrier
+	 * @throws EE_Error
+	 */
+	private function _extract_related_models_from_sub_params_array_keys(
+		$sub_query_params,
+		EE_Model_Query_Info_Carrier $model_query_info_carrier,
+		$query_param_type
+	) {
+		if (! empty($sub_query_params)) {
+			$sub_query_params = (array) $sub_query_params;
+			foreach ($sub_query_params as $param => $possibly_array_of_params) {
+				// $param could be simply 'EVT_ID', or it could be 'Registrations.REG_ID', or even 'Registrations.Transactions.Payments.PAY_amount'
+				$this->_extract_related_model_info_from_query_param(
+					$param,
+					$model_query_info_carrier,
+					$query_param_type
+				);
+				// if $possibly_array_of_params is an array, try recursing into it, searching for keys which
+				// indicate needed joins. Eg, array('NOT'=>array('Registration.TXN_ID'=>23)). In this case, we tried
+				// extracting models out of the 'NOT', which obviously wasn't successful, and then we recurse into the value
+				// of array('Registration.TXN_ID'=>23)
+				$query_param_sans_stars =
+					$this->_remove_stars_and_anything_after_from_condition_query_param_key($param);
+				if (in_array($query_param_sans_stars, $this->_logic_query_param_keys, true)) {
+					if (! is_array($possibly_array_of_params)) {
+						throw new EE_Error(
+							sprintf(
+								esc_html__(
+									"You used a special where query param %s, but the value isn't an array of where query params, it's just %s'. It should be an array, eg array('EVT_ID'=>23,'OR'=>array('Venue.VNU_ID'=>32,'Venue.VNU_name'=>'monkey_land'))",
+									"event_espresso"
+								),
+								$param,
+								$possibly_array_of_params
+							)
+						);
+					}
+					$this->_extract_related_models_from_sub_params_array_keys(
+						$possibly_array_of_params,
+						$model_query_info_carrier,
+						$query_param_type
+					);
+				} elseif (
+					$query_param_type === 0 // ie WHERE
+					&& is_array($possibly_array_of_params)
+					&& isset($possibly_array_of_params[2])
+					&& $possibly_array_of_params[2] == true
+				) {
+					// then $possible_array_of_params looks something like array('<','DTT_sold',true)
+					// indicating that $possible_array_of_params[1] is actually a field name,
+					// from which we should extract query parameters!
+					if (! isset($possibly_array_of_params[0], $possibly_array_of_params[1])) {
+						throw new EE_Error(
+							sprintf(
+								esc_html__(
+									"Improperly formed query parameter %s. It should be numerically indexed like array('<','DTT_sold',true); but you provided %s",
+									"event_espresso"
+								),
+								$query_param_type,
+								implode(",", $possibly_array_of_params)
+							)
+						);
+					}
+					$this->_extract_related_model_info_from_query_param(
+						$possibly_array_of_params[1],
+						$model_query_info_carrier,
+						$query_param_type
+					);
+				}
+			}
+		}
+		return $model_query_info_carrier;
+	}
+
+
+	/**
+	 * For extracting related models from forced_joins, where the array values contain the info about what
+	 * models to join with. Eg an array like array('Attendee','Price.Price_Type');
+	 *
+	 * @param array                       $sub_query_params @see
+	 *                                                      https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @param EE_Model_Query_Info_Carrier $model_query_info_carrier
+	 * @param string                      $query_param_type one of $this->_allowed_query_params
+	 * @return EE_Model_Query_Info_Carrier
+	 * @throws EE_Error
+	 */
+	private function _extract_related_models_from_sub_params_array_values(
+		$sub_query_params,
+		EE_Model_Query_Info_Carrier $model_query_info_carrier,
+		$query_param_type
+	) {
+		if (! empty($sub_query_params)) {
+			if (! is_array($sub_query_params)) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__("Query parameter %s should be an array, but it isn't.", "event_espresso"),
+						$sub_query_params
+					)
+				);
+			}
+			foreach ($sub_query_params as $param) {
+				// $param could be simply 'EVT_ID', or it could be 'Registrations.REG_ID', or even 'Registrations.Transactions.Payments.PAY_amount'
+				$this->_extract_related_model_info_from_query_param(
+					$param,
+					$model_query_info_carrier,
+					$query_param_type
+				);
+			}
+		}
+		return $model_query_info_carrier;
+	}
+
+
+	/**
+	 * Extract all the query parts from  model query params
+	 * and put into a EEM_Related_Model_Info_Carrier for easy extraction into a query. We create this object
+	 * instead of directly constructing the SQL because often we need to extract info from the $query_params
+	 * but use them in a different order. Eg, we need to know what models we are querying
+	 * before we know what joins to perform. However, we need to know what data types correspond to which fields on
+	 * other models before we can finalize the where clause SQL.
+	 *
+	 * @param array $query_params @see
+	 *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Model_Query_Info_Carrier
+	 * @throws EE_Error
+	 * @throws ModelConfigurationException*@throws ReflectionException
+	 * @throws ReflectionException
+	 */
+	public function _create_model_query_info_carrier($query_params)
+	{
+		if (! is_array($query_params)) {
+			EE_Error::doing_it_wrong(
+				'EEM_Base::_create_model_query_info_carrier',
+				sprintf(
+					esc_html__(
+						'$query_params should be an array, you passed a variable of type %s',
+						'event_espresso'
+					),
+					gettype($query_params)
+				),
+				'4.6.0'
+			);
+			$query_params = [];
+		}
+		$query_params[0] = isset($query_params[0]) ? $query_params[0] : [];
+		// first check if we should alter the query to account for caps or not
+		// because the caps might require us to do extra joins
+		if (isset($query_params['caps']) && $query_params['caps'] !== 'none') {
+			$query_params[0] = array_replace_recursive(
+				$query_params[0],
+				$this->caps_where_conditions($query_params['caps'])
+			);
+		}
+
+		// check if we should alter the query to remove data related to protected
+		// custom post types
+		if (isset($query_params['exclude_protected']) && $query_params['exclude_protected'] === true) {
+			$where_param_key_for_password = $this->modelChainAndPassword();
+			// only include if related to a cpt where no password has been set
+			$query_params[0]['OR*nopassword'] = [
+				$where_param_key_for_password       => '',
+				$where_param_key_for_password . '*' => ['IS_NULL'],
+			];
+		}
+		$query_object = $this->_extract_related_models_from_query($query_params);
+		// verify where_query_params has NO numeric indexes.... that's simply not how you use it!
+		foreach ($query_params[0] as $key => $value) {
+			if (is_int($key)) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							"WHERE query params must NOT be numerically-indexed. You provided the array key '%s' for value '%s' while querying model %s. All the query params provided were '%s' Please read documentation on EEM_Base::get_all.",
+							"event_espresso"
+						),
+						$key,
+						var_export($value, true),
+						var_export($query_params, true),
+						get_class($this)
+					)
+				);
+			}
+		}
+		if (
+			array_key_exists('default_where_conditions', $query_params)
+			&& ! empty($query_params['default_where_conditions'])
+		) {
+			$use_default_where_conditions = $query_params['default_where_conditions'];
+		} else {
+			$use_default_where_conditions = EEM_Base::default_where_conditions_all;
+		}
+		$query_params[0] = array_merge(
+			$this->_get_default_where_conditions_for_models_in_query(
+				$query_object,
+				$use_default_where_conditions,
+				$query_params[0]
+			),
+			$query_params[0]
+		);
+		$query_object->set_where_sql($this->_construct_where_clause($query_params[0]));
+		// if this is a "on_join_limit" then we are limiting on on a specific table in a multi_table join.
+		// So we need to setup a subquery and use that for the main join.
+		// Note for now this only works on the primary table for the model.
+		// So for instance, you could set the limit array like this:
+		// array( 'on_join_limit' => array('Primary_Table_Alias', array(1,10) ) )
+		if (array_key_exists('on_join_limit', $query_params) && ! empty($query_params['on_join_limit'])) {
+			$query_object->set_main_model_join_sql(
+				$this->_construct_limit_join_select(
+					$query_params['on_join_limit'][0],
+					$query_params['on_join_limit'][1]
+				)
+			);
+		}
+		// set limit
+		if (array_key_exists('limit', $query_params)) {
+			if (is_array($query_params['limit'])) {
+				if (! isset($query_params['limit'][0], $query_params['limit'][1])) {
+					$e = sprintf(
+						esc_html__(
+							"Invalid DB query. You passed '%s' for the LIMIT, but only the following are valid: an integer, string representing an integer, a string like 'int,int', or an array like array(int,int)",
+							"event_espresso"
+						),
+						http_build_query($query_params['limit'])
+					);
+					throw new EE_Error($e . "|" . $e);
+				}
+				// they passed us an array for the limit. Assume it's like array(50,25), meaning offset by 50, and get 25
+				$query_object->set_limit_sql(" LIMIT " . $query_params['limit'][0] . "," . $query_params['limit'][1]);
+			} elseif (! empty($query_params['limit'])) {
+				$query_object->set_limit_sql(" LIMIT " . $query_params['limit']);
+			}
+		}
+		// set order by
+		if (array_key_exists('order_by', $query_params)) {
+			if (is_array($query_params['order_by'])) {
+				// if they're using 'order_by' as an array, they can't use 'order' (because 'order_by' must
+				// specify whether to ascend or descend on each field. Eg 'order_by'=>array('EVT_ID'=>'ASC'). So
+				// including 'order' wouldn't make any sense if 'order_by' has already specified which way to order!
+				if (array_key_exists('order', $query_params)) {
+					throw new EE_Error(
+						sprintf(
+							esc_html__(
+								"In querying %s, we are using query parameter 'order_by' as an array (keys:%s,values:%s), and so we can't use query parameter 'order' (value %s). You should just use the 'order_by' parameter ",
+								"event_espresso"
+							),
+							get_class($this),
+							implode(", ", array_keys($query_params['order_by'])),
+							implode(", ", $query_params['order_by']),
+							$query_params['order']
+						)
+					);
+				}
+				$this->_extract_related_models_from_sub_params_array_keys(
+					$query_params['order_by'],
+					$query_object,
+					'order_by'
+				);
+				// assume it's an array of fields to order by
+				$order_array = [];
+				foreach ($query_params['order_by'] as $field_name_to_order_by => $order) {
+					$order         = $this->_extract_order($order);
+					$order_array[] = $this->_deduce_column_name_from_query_param($field_name_to_order_by) . SP . $order;
+				}
+				$query_object->set_order_by_sql(" ORDER BY " . implode(",", $order_array));
+			} elseif (! empty($query_params['order_by'])) {
+				$this->_extract_related_model_info_from_query_param(
+					$query_params['order_by'],
+					$query_object,
+					'order',
+					$query_params['order_by']
+				);
+				$order = isset($query_params['order'])
+					? $this->_extract_order($query_params['order'])
+					: 'DESC';
+				$query_object->set_order_by_sql(
+					" ORDER BY " . $this->_deduce_column_name_from_query_param($query_params['order_by']) . SP . $order
+				);
+			}
+		}
+		// if 'order_by' wasn't set, maybe they are just using 'order' on its own?
+		if (
+			! array_key_exists('order_by', $query_params)
+			&& array_key_exists('order', $query_params)
+			&& ! empty($query_params['order'])
+		) {
+			$pk_field = $this->get_primary_key_field();
+			$order    = $this->_extract_order($query_params['order']);
+			$query_object->set_order_by_sql(" ORDER BY " . $pk_field->get_qualified_column() . SP . $order);
+		}
+		// set group by
+		if (array_key_exists('group_by', $query_params)) {
+			if (is_array($query_params['group_by'])) {
+				// it's an array, so assume we'll be grouping by a bunch of stuff
+				$group_by_array = [];
+				foreach ($query_params['group_by'] as $field_name_to_group_by) {
+					$group_by_array[] = $this->_deduce_column_name_from_query_param($field_name_to_group_by);
+				}
+				$query_object->set_group_by_sql(" GROUP BY " . implode(", ", $group_by_array));
+			} elseif (! empty($query_params['group_by'])) {
+				$query_object->set_group_by_sql(
+					" GROUP BY " . $this->_deduce_column_name_from_query_param($query_params['group_by'])
+				);
+			}
+		}
+		// set having
+		if (array_key_exists('having', $query_params) && $query_params['having']) {
+			$query_object->set_having_sql($this->_construct_having_clause($query_params['having']));
+		}
+		// now, just verify they didn't pass anything wack
+		foreach ($query_params as $query_key => $query_value) {
+			if (! in_array($query_key, $this->_allowed_query_params, true)) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							"You passed %s as a query parameter to %s, which is illegal! The allowed query parameters are %s",
+							'event_espresso'
+						),
+						$query_key,
+						get_class($this),
+						//                      print_r( $this->_allowed_query_params, TRUE )
+						implode(',', $this->_allowed_query_params)
+					)
+				);
+			}
+		}
+		$main_model_join_sql = $query_object->get_main_model_join_sql();
+		if (empty($main_model_join_sql)) {
+			$query_object->set_main_model_join_sql($this->_construct_internal_join());
+		}
+		return $query_object;
+	}
+
+
+	/**
+	 * Gets the where conditions that should be imposed on the query based on the
+	 * context (eg reading frontend, backend, edit or delete).
+	 *
+	 * @param string $context one of EEM_Base::valid_cap_contexts()
+	 * @return array @see
+	 *               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @throws EE_Error
+	 */
+	public function caps_where_conditions($context = self::caps_read)
+	{
+		EEM_Base::verify_is_valid_cap_context($context);
+		$cap_where_conditions = [];
+		$cap_restrictions     = $this->caps_missing($context);
+		/**
+		 * @var $cap_restrictions EE_Default_Where_Conditions[]
+		 */
+		foreach ($cap_restrictions as $cap => $restriction_if_no_cap) {
+			$cap_where_conditions = array_replace_recursive(
+				$cap_where_conditions,
+				$restriction_if_no_cap->get_default_where_conditions()
+			);
+		}
+		return apply_filters(
+			'FHEE__EEM_Base__caps_where_conditions__return',
+			$cap_where_conditions,
+			$this,
+			$context,
+			$cap_restrictions
+		);
+	}
+
+
+	/**
+	 * Verifies that $should_be_order_string is in $this->_allowed_order_values,
+	 * otherwise throws an exception
+	 *
+	 * @param string $should_be_order_string
+	 * @return string either ASC, asc, DESC or desc
+	 * @throws EE_Error
+	 */
+	private function _extract_order($should_be_order_string)
+	{
+		if (in_array($should_be_order_string, $this->_allowed_order_values)) {
+			return $should_be_order_string;
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					"While performing a query on '%s', tried to use '%s' as an order parameter. ",
+					"event_espresso"
+				),
+				get_class($this),
+				$should_be_order_string
+			)
+		);
+	}
+
+
+	/**
+	 * Looks at all the models which are included in this query, and asks each
+	 * for their universal_where_params, and returns them in the same format as $query_params[0] (where),
+	 * so they can be merged
+	 *
+	 * @param EE_Model_Query_Info_Carrier $query_info_carrier
+	 * @param string                      $use_default_where_conditions can be 'none','other_models_only', or 'all'.
+	 *                                                                  'none' means NO default where conditions will
+	 *                                                                  be used AT ALL during this query.
+	 *                                                                  'other_models_only' means default where
+	 *                                                                  conditions from other models will be used, but
+	 *                                                                  not for this primary model. 'all', the default,
+	 *                                                                  means default where conditions will apply as
+	 *                                                                  normal
+	 * @param array                       $where_query_params           @see
+	 *                                                                  https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @throws EE_Error
+	 */
+	private function _get_default_where_conditions_for_models_in_query(
+		EE_Model_Query_Info_Carrier $query_info_carrier,
+		$use_default_where_conditions = EEM_Base::default_where_conditions_all,
+		$where_query_params = []
+	) {
+		$allowed_used_default_where_conditions_values = EEM_Base::valid_default_where_conditions();
+		if (! in_array($use_default_where_conditions, $allowed_used_default_where_conditions_values)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"You passed an invalid value to the query parameter 'default_where_conditions' of '%s'. Allowed values are %s",
+						"event_espresso"
+					),
+					$use_default_where_conditions,
+					implode(", ", $allowed_used_default_where_conditions_values)
+				)
+			);
+		}
+		$universal_query_params = [];
+		if ($this->_should_use_default_where_conditions($use_default_where_conditions, true)) {
+			$universal_query_params = $this->_get_default_where_conditions();
+		} elseif ($this->_should_use_minimum_where_conditions($use_default_where_conditions, true)) {
+			$universal_query_params = $this->_get_minimum_where_conditions();
+		}
+		foreach ($query_info_carrier->get_model_names_included() as $model_relation_path => $model_name) {
+			$related_model = $this->get_related_model_obj($model_name);
+			if ($this->_should_use_default_where_conditions($use_default_where_conditions, false)) {
+				$related_model_universal_where_params =
+					$related_model->_get_default_where_conditions($model_relation_path);
+			} elseif ($this->_should_use_minimum_where_conditions($use_default_where_conditions, false)) {
+				$related_model_universal_where_params =
+					$related_model->_get_minimum_where_conditions($model_relation_path);
+			} else {
+				// we don't want to add full or even minimum default where conditions from this model, so just continue
+				continue;
+			}
+			$overrides              = $this->_override_defaults_or_make_null_friendly(
+				$related_model_universal_where_params,
+				$where_query_params,
+				$related_model,
+				$model_relation_path
+			);
+			$universal_query_params = EEH_Array::merge_arrays_and_overwrite_keys(
+				$universal_query_params,
+				$overrides
+			);
+		}
+		return $universal_query_params;
+	}
+
+
+	/**
+	 * Determines whether or not we should use default where conditions for the model in question
+	 * (this model, or other related models).
+	 * Basically, we should use default where conditions on this model if they have requested to use them on all models,
+	 * this model only, or to use minimum where conditions on all other models and normal where conditions on this one.
+	 * We should use default where conditions on related models when they requested to use default where conditions
+	 * on all models, or specifically just on other related models
+	 *
+	 * @param      $default_where_conditions_value
+	 * @param bool $for_this_model false means this is for OTHER related models
+	 * @return bool
+	 */
+	private function _should_use_default_where_conditions($default_where_conditions_value, $for_this_model = true)
+	{
+		return (
+				   $for_this_model
+				   && in_array(
+					   $default_where_conditions_value,
+					   [
+						   EEM_Base::default_where_conditions_all,
+						   EEM_Base::default_where_conditions_this_only,
+						   EEM_Base::default_where_conditions_minimum_others,
+					   ],
+					   true
+				   )
+			   )
+			   || (
+				   ! $for_this_model
+				   && in_array(
+					   $default_where_conditions_value,
+					   [
+						   EEM_Base::default_where_conditions_all,
+						   EEM_Base::default_where_conditions_others_only,
+					   ],
+					   true
+				   )
+			   );
+	}
+
+
+	/**
+	 * Determines whether or not we should use default minimum conditions for the model in question
+	 * (this model, or other related models).
+	 * Basically, we should use minimum where conditions on this model only if they requested all models to use minimum
+	 * where conditions.
+	 * We should use minimum where conditions on related models if they requested to use minimum where conditions
+	 * on this model or others
+	 *
+	 * @param      $default_where_conditions_value
+	 * @param bool $for_this_model false means this is for OTHER related models
+	 * @return bool
+	 */
+	private function _should_use_minimum_where_conditions($default_where_conditions_value, $for_this_model = true)
+	{
+		return (
+				   $for_this_model
+				   && $default_where_conditions_value === EEM_Base::default_where_conditions_minimum_all
+			   )
+			   || (
+				   ! $for_this_model
+				   && in_array(
+					   $default_where_conditions_value,
+					   [
+						   EEM_Base::default_where_conditions_minimum_others,
+						   EEM_Base::default_where_conditions_minimum_all,
+					   ],
+					   true
+				   )
+			   );
+	}
+
+
+	/**
+	 * Checks if any of the defaults have been overridden. If there are any that AREN'T overridden,
+	 * then we also add a special where condition which allows for that model's primary key
+	 * to be null (which is important for JOINs. Eg, if you want to see all Events ordered by Venue's name,
+	 * then Event's with NO Venue won't appear unless you allow VNU_ID to be NULL)
+	 *
+	 * @param array    $default_where_conditions
+	 * @param array    $provided_where_conditions
+	 * @param EEM_Base $model
+	 * @param string   $model_relation_path like 'Transaction.Payment.'
+	 * @return array @see
+	 *               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @throws EE_Error
+	 */
+	private function _override_defaults_or_make_null_friendly(
+		$default_where_conditions,
+		$provided_where_conditions,
+		$model,
+		$model_relation_path
+	) {
+		$null_friendly_where_conditions = [];
+		$none_overridden                = true;
+		$or_condition_key_for_defaults  = 'OR*' . get_class($model);
+		foreach ($default_where_conditions as $key => $val) {
+			if (isset($provided_where_conditions[ $key ])) {
+				$none_overridden = false;
+			} else {
+				$null_friendly_where_conditions[ $or_condition_key_for_defaults ]['AND'][ $key ] = $val;
+			}
+		}
+		if ($none_overridden && $default_where_conditions) {
+			if ($model->has_primary_key_field()) {
+				$null_friendly_where_conditions[ $or_condition_key_for_defaults ][ $model_relation_path
+																				   . "."
+																				   . $model->primary_key_name() ] =
+					['IS NULL'];
+			}/*else{
                 //@todo NO PK, use other defaults
             }*/
-        }
-        return $null_friendly_where_conditions;
-    }
-
-
-    /**
-     * Uses the _default_where_conditions_strategy set during __construct() to get
-     * default where conditions on all get_all, update, and delete queries done by this model.
-     * Use the same syntax as client code. Eg on the Event model, use array('Event.EVT_post_type'=>'esp_event'),
-     * NOT array('Event_CPT.post_type'=>'esp_event').
-     *
-     * @param string $model_relation_path eg, path from Event to Payment is "Registration.Transaction.Payment."
-     * @return array @see
-     *                                    https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @throws EE_Error
-     * @throws EE_Error
-     */
-    private function _get_default_where_conditions($model_relation_path = '')
-    {
-        if ($this->_ignore_where_strategy) {
-            return [];
-        }
-        return $this->_default_where_conditions_strategy->get_default_where_conditions($model_relation_path);
-    }
-
-
-    /**
-     * Uses the _minimum_where_conditions_strategy set during __construct() to get
-     * minimum where conditions on all get_all, update, and delete queries done by this model.
-     * Use the same syntax as client code. Eg on the Event model, use array('Event.EVT_post_type'=>'esp_event'),
-     * NOT array('Event_CPT.post_type'=>'esp_event').
-     * Similar to _get_default_where_conditions
-     *
-     * @param string $model_relation_path eg, path from Event to Payment is "Registration.Transaction.Payment."
-     * @return array @see
-     *                                    https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @throws EE_Error
-     * @throws EE_Error
-     */
-    protected function _get_minimum_where_conditions($model_relation_path = '')
-    {
-        if ($this->_ignore_where_strategy) {
-            return [];
-        }
-        return $this->_minimum_where_conditions_strategy->get_default_where_conditions($model_relation_path);
-    }
-
-
-    /**
-     * Creates the string of SQL for the select part of a select query, everything behind SELECT and before FROM.
-     * Eg, "Event.post_id, Event.post_name,Event_Detail.EVT_ID..."
-     *
-     * @param EE_Model_Query_Info_Carrier $model_query_info
-     * @return string
-     * @throws EE_Error
-     */
-    private function _construct_default_select_sql(EE_Model_Query_Info_Carrier $model_query_info)
-    {
-        $selects = $this->_get_columns_to_select_for_this_model();
-        foreach (
-            $model_query_info->get_model_names_included() as $model_relation_chain => $name_of_other_model_included
-        ) {
-            $other_model_included = $this->get_related_model_obj($name_of_other_model_included);
-            $other_model_selects  = $other_model_included->_get_columns_to_select_for_this_model($model_relation_chain);
-            foreach ($other_model_selects as $key => $value) {
-                $selects[] = $value;
-            }
-        }
-        return implode(", ", $selects);
-    }
-
-
-    /**
-     * Gets an array of columns to select for this model, which are necessary for it to create its objects.
-     * So that's going to be the columns for all the fields on the model
-     *
-     * @param string $model_relation_chain like 'Question.Question_Group.Event'
-     * @return array numerically indexed, values are columns to select and rename, eg "Event.ID AS 'Event.ID'"
-     */
-    public function _get_columns_to_select_for_this_model($model_relation_chain = '')
-    {
-        $fields                                       = $this->field_settings();
-        $selects                                      = [];
-        $table_alias_with_model_relation_chain_prefix =
-            EE_Model_Parser::extract_table_alias_model_relation_chain_prefix(
-                $model_relation_chain,
-                $this->get_this_model_name()
-            );
-        foreach ($fields as $field_obj) {
-            $selects[] = $table_alias_with_model_relation_chain_prefix
-                         . $field_obj->get_table_alias()
-                         . "."
-                         . $field_obj->get_table_column()
-                         . " AS '"
-                         . $table_alias_with_model_relation_chain_prefix
-                         . $field_obj->get_table_alias()
-                         . "."
-                         . $field_obj->get_table_column()
-                         . "'";
-        }
-        // make sure we are also getting the PKs of each table
-        $tables = $this->get_tables();
-        if (count($tables) > 1) {
-            foreach ($tables as $table_obj) {
-                $qualified_pk_column = $table_alias_with_model_relation_chain_prefix
-                                       . $table_obj->get_fully_qualified_pk_column();
-                if (! in_array($qualified_pk_column, $selects)) {
-                    $selects[] = "$qualified_pk_column AS '$qualified_pk_column'";
-                }
-            }
-        }
-        return $selects;
-    }
-
-
-    /**
-     * Given a $query_param like 'Registration.Transaction.TXN_ID', pops off 'Registration.',
-     * gets the join statement for it; gets the data types for it; and passes the remaining 'Transaction.TXN_ID'
-     * onto its related Transaction object to do the same. Returns an EE_Join_And_Data_Types object which contains the
-     * SQL for joining, and the data types
-     *
-     * @param null|string                 $original_query_param
-     * @param string                      $query_param          like Registration.Transaction.TXN_ID
-     * @param EE_Model_Query_Info_Carrier $passed_in_query_info
-     * @param string                      $query_param_type     like Registration.Transaction.TXN_ID
-     *                                                          or 'PAY_ID'. Otherwise, we don't expect there to be a
-     *                                                          column name. We only want model names, eg 'Event.Venue'
-     *                                                          or 'Registration's
-     * @param string                      $original_query_param what it originally was (eg
-     *                                                          Registration.Transaction.TXN_ID). If null, we assume it
-     *                                                          matches $query_param
-     * @return void only modifies the EEM_Related_Model_Info_Carrier passed into it
-     * @throws EE_Error
-     */
-    private function _extract_related_model_info_from_query_param(
-        $query_param,
-        EE_Model_Query_Info_Carrier $passed_in_query_info,
-        $query_param_type,
-        $original_query_param = null
-    ) {
-        if ($original_query_param === null) {
-            $original_query_param = $query_param;
-        }
-        $query_param = $this->_remove_stars_and_anything_after_from_condition_query_param_key($query_param);
-        // check to see if we have a field on this model
-        $this_model_fields = $this->field_settings(true);
-        if (array_key_exists($query_param, $this_model_fields)) {
-            $field_is_allowed = in_array(
-                $query_param_type,
-                [0, 'where', 'having', 'order_by', 'group_by', 'order', 'custom_selects'],
-                true
-            );
-            if ($field_is_allowed) {
-                return;
-            }
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "Using a field name (%s) on model %s is not allowed on this query param type '%s'. Original query param was %s",
-                        "event_espresso"
-                    ),
-                    $query_param,
-                    get_class($this),
-                    $query_param_type,
-                    $original_query_param
-                )
-            );
-        }
-        // check if this is a special logic query param
-        if (in_array($query_param, $this->_logic_query_param_keys, true)) {
-            $operator_is_allowed = in_array($query_param_type, ['where', 'having', 0, 'custom_selects'], true);
-            if ($operator_is_allowed) {
-                return;
-            }
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'Logic query params ("%1$s") are being used incorrectly with the following query param ("%2$s") on model %3$s. %4$sAdditional Info:%4$s%5$s',
-                        'event_espresso'
-                    ),
-                    implode('", "', $this->_logic_query_param_keys),
-                    $query_param,
-                    get_class($this),
-                    '<br />',
-                    "\t"
-                    . ' $passed_in_query_info = <pre>'
-                    . print_r($passed_in_query_info, true)
-                    . '</pre>'
-                    . "\n\t"
-                    . ' $query_param_type = '
-                    . $query_param_type
-                    . "\n\t"
-                    . ' $original_query_param = '
-                    . $original_query_param
-                )
-            );
-        }
-        // check if it's a custom selection
-        if (
-            $this->_custom_selections instanceof CustomSelects
-            && in_array($query_param, $this->_custom_selections->columnAliases(), true)
-        ) {
-            return;
-        }
-        // check if has a model name at the beginning
-        // and
-        // check if it's a field on a related model
-        if (
-            $this->extractJoinModelFromQueryParams(
-                $passed_in_query_info,
-                $query_param,
-                $original_query_param,
-                $query_param_type
-            )
-        ) {
-            return;
-        }
-
-        // ok so $query_param didn't start with a model name
-        // and we previously confirmed it wasn't a logic query param or field on the current model
-        // it's wack, that's what it is
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    "There is no model named '%s' related to %s. Query param type is %s and original query param is %s",
-                    "event_espresso"
-                ),
-                $query_param,
-                get_class($this),
-                $query_param_type,
-                $original_query_param
-            )
-        );
-    }
-
-
-    /**
-     * Extracts any possible join model information from the provided possible_join_string.
-     * This method will read the provided $possible_join_string value and determine if there are any possible model
-     * join
-     * parts that should be added to the query.
-     *
-     * @param EE_Model_Query_Info_Carrier $query_info_carrier
-     * @param string                      $possible_join_string  Such as Registration.REG_ID, or Registration
-     * @param null|string                 $original_query_param
-     * @param string                      $query_parameter_type  The type for the source of the $possible_join_string
-     *                                                           ('where', 'order_by', 'group_by', 'custom_selects'
-     *                                                           etc.)
-     * @return bool  returns true if a join was added and false if not.
-     * @throws EE_Error
-     */
-    private function extractJoinModelFromQueryParams(
-        EE_Model_Query_Info_Carrier $query_info_carrier,
-        $possible_join_string,
-        $original_query_param,
-        $query_parameter_type
-    ) {
-        foreach ($this->_model_relations as $valid_related_model_name => $relation_obj) {
-            if (strpos($possible_join_string, $valid_related_model_name . ".") === 0) {
-                $this->_add_join_to_model($valid_related_model_name, $query_info_carrier, $original_query_param);
-                $possible_join_string = substr($possible_join_string, strlen($valid_related_model_name . "."));
-                if ($possible_join_string === '') {
-                    // nothing left to $query_param
-                    // we should actually end in a field name, not a model like this!
-                    throw new EE_Error(
-                        sprintf(
-                            esc_html__(
-                                "Query param '%s' (of type %s on model %s) shouldn't end on a period (.) ",
-                                "event_espresso"
-                            ),
-                            $possible_join_string,
-                            $query_parameter_type,
-                            get_class($this),
-                            $valid_related_model_name
-                        )
-                    );
-                }
-                $related_model_obj = $this->get_related_model_obj($valid_related_model_name);
-                $related_model_obj->_extract_related_model_info_from_query_param(
-                    $possible_join_string,
-                    $query_info_carrier,
-                    $query_parameter_type,
-                    $original_query_param
-                );
-                return true;
-            }
-            if ($possible_join_string === $valid_related_model_name) {
-                $this->_add_join_to_model(
-                    $valid_related_model_name,
-                    $query_info_carrier,
-                    $original_query_param
-                );
-                return true;
-            }
-        }
-        return false;
-    }
-
-
-    /**
-     * Extracts related models from Custom Selects and sets up any joins for those related models.
-     *
-     * @param EE_Model_Query_Info_Carrier $query_info_carrier
-     * @throws EE_Error
-     */
-    private function extractRelatedModelsFromCustomSelects(EE_Model_Query_Info_Carrier $query_info_carrier)
-    {
-        if (
-            $this->_custom_selections instanceof CustomSelects
-            && (
-                $this->_custom_selections->type() === CustomSelects::TYPE_STRUCTURED
-                || $this->_custom_selections->type() == CustomSelects::TYPE_COMPLEX
-            )
-        ) {
-            $original_selects = $this->_custom_selections->originalSelects();
-            foreach ($original_selects as $alias => $select_configuration) {
-                $this->extractJoinModelFromQueryParams(
-                    $query_info_carrier,
-                    $select_configuration[0],
-                    $select_configuration[0],
-                    'custom_selects'
-                );
-            }
-        }
-    }
-
-
-    /**
-     * Privately used by _extract_related_model_info_from_query_param to add a join to $model_name
-     * and store it on $passed_in_query_info
-     *
-     * @param string                      $model_name
-     * @param EE_Model_Query_Info_Carrier $passed_in_query_info
-     * @param string                      $original_query_param used to extract the relation chain between the queried
-     *                                                          model and $model_name. Eg, if we are querying Event,
-     *                                                          and are adding a join to 'Payment' with the original
-     *                                                          query param key
-     *                                                          'Registration.Transaction.Payment.PAY_amount', we want
-     *                                                          to extract 'Registration.Transaction.Payment', in case
-     *                                                          Payment wants to add default query params so that it
-     *                                                          will know what models to prepend onto its default query
-     *                                                          params or in case it wants to rename tables (in case
-     *                                                          there are multiple joins to the same table)
-     * @return void
-     * @throws EE_Error
-     */
-    private function _add_join_to_model(
-        $model_name,
-        EE_Model_Query_Info_Carrier $passed_in_query_info,
-        $original_query_param
-    ) {
-        $relation_obj         = $this->related_settings_for($model_name);
-        $model_relation_chain = EE_Model_Parser::extract_model_relation_chain($model_name, $original_query_param);
-        // check if the relation is HABTM, because then we're essentially doing two joins
-        // If so, join first to the JOIN table, and add its data types, and then continue as normal
-        if ($relation_obj instanceof EE_HABTM_Relation) {
-            $join_model_obj = $relation_obj->get_join_model();
-            // replace the model specified with the join model for this relation chain, whi
-            $relation_chain_to_join_model =
-                EE_Model_Parser::replace_model_name_with_join_model_name_in_model_relation_chain(
-                    $model_name,
-                    $join_model_obj->get_this_model_name(),
-                    $model_relation_chain
-                );
-            $passed_in_query_info->merge(
-                new EE_Model_Query_Info_Carrier(
-                    [$relation_chain_to_join_model => $join_model_obj->get_this_model_name()],
-                    $relation_obj->get_join_to_intermediate_model_statement($relation_chain_to_join_model)
-                )
-            );
-        }
-        // now just join to the other table pointed to by the relation object, and add its data types
-        $passed_in_query_info->merge(
-            new EE_Model_Query_Info_Carrier(
-                [$model_relation_chain => $model_name],
-                $relation_obj->get_join_statement($model_relation_chain)
-            )
-        );
-    }
-
-
-    /**
-     * Constructs SQL for where clause, like "WHERE Event.ID = 23 AND Transaction.amount > 100" etc.
-     *
-     * @param array $where_params @see
-     *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @return string of SQL
-     * @throws EE_Error
-     */
-    private function _construct_where_clause($where_params)
-    {
-        $SQL = $this->_construct_condition_clause_recursive($where_params, ' AND ');
-        if ($SQL) {
-            return " WHERE " . $SQL;
-        }
-        return '';
-    }
-
-
-    /**
-     * Just like the _construct_where_clause, except prepends 'HAVING' instead of 'WHERE',
-     * and should be passed HAVING parameters, not WHERE parameters
-     *
-     * @param array $having_params
-     * @return string
-     * @throws EE_Error
-     */
-    private function _construct_having_clause($having_params)
-    {
-        $SQL = $this->_construct_condition_clause_recursive($having_params, ' AND ');
-        if ($SQL) {
-            return " HAVING " . $SQL;
-        }
-        return '';
-    }
-
-
-    /**
-     * Used for creating nested WHERE conditions. Eg "WHERE ! (Event.ID = 3 OR ( Event_Meta.meta_key = 'bob' AND
-     * Event_Meta.meta_value = 'foo'))"
-     *
-     * @param array  $where_params @see
-     *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @param string $glue         joins each subclause together. Should really only be " AND " or " OR "...
-     * @return string of SQL
-     * @throws EE_Error
-     */
-    private function _construct_condition_clause_recursive($where_params, $glue = ' AND')
-    {
-        $where_clauses = [];
-        foreach ($where_params as $query_param => $op_and_value_or_sub_condition) {
-            $query_param = $this->_remove_stars_and_anything_after_from_condition_query_param_key($query_param);
-            if (in_array($query_param, $this->_logic_query_param_keys, true)) {
-                switch ($query_param) {
-                    case 'not':
-                    case 'NOT':
-                        $where_clauses[] = "! ("
-                                           . $this->_construct_condition_clause_recursive(
-                                               $op_and_value_or_sub_condition,
-                                               $glue
-                                           )
-                                           . ")";
-                        break;
-                    case 'and':
-                    case 'AND':
-                        $where_clauses[] = " ("
-                                           . $this->_construct_condition_clause_recursive(
-                                               $op_and_value_or_sub_condition,
-                                               ' AND '
-                                           )
-                                           . ")";
-                        break;
-                    case 'or':
-                    case 'OR':
-                        $where_clauses[] = " ("
-                                           . $this->_construct_condition_clause_recursive(
-                                               $op_and_value_or_sub_condition,
-                                               ' OR '
-                                           )
-                                           . ")";
-                        break;
-                }
-            } else {
-                $field_obj = $this->_deduce_field_from_query_param($query_param);
-                // if it's not a normal field, maybe it's a custom selection?
-                if (! $field_obj) {
-                    if ($this->_custom_selections instanceof CustomSelects) {
-                        $field_obj = $this->_custom_selections->getDataTypeForAlias($query_param);
-                    } else {
-                        throw new EE_Error(
-                            sprintf(
-                                esc_html__(
-                                    "%s is neither a valid model field name, nor a custom selection",
-                                    "event_espresso"
-                                ),
-                                $query_param
-                            )
-                        );
-                    }
-                }
-                $op_and_value_sql = $this->_construct_op_and_value($op_and_value_or_sub_condition, $field_obj);
-                $where_clauses[]  = $this->_deduce_column_name_from_query_param($query_param) . SP . $op_and_value_sql;
-            }
-        }
-        return $where_clauses ? implode($glue, $where_clauses) : '';
-    }
-
-
-    /**
-     * Takes the input parameter and extract the table name (alias) and column name
-     *
-     * @param string $query_param like Registration.Transaction.TXN_ID, Event.Datetime.start_time, or REG_ID
-     * @return string table alias and column name for SQL, eg "Transaction.TXN_ID"
-     * @throws EE_Error
-     */
-    private function _deduce_column_name_from_query_param($query_param)
-    {
-        $field = $this->_deduce_field_from_query_param($query_param);
-        if ($field) {
-            $table_alias_prefix = EE_Model_Parser::extract_table_alias_model_relation_chain_from_query_param(
-                $field->get_model_name(),
-                $query_param
-            );
-            return $table_alias_prefix . $field->get_qualified_column();
-        }
-        if (
-            $this->_custom_selections instanceof CustomSelects
-            && in_array($query_param, $this->_custom_selections->columnAliases(), true)
-        ) {
-            // maybe it's custom selection item?
-            // if so, just use it as the "column name"
-            return $query_param;
-        }
-        $custom_select_aliases = $this->_custom_selections instanceof CustomSelects
-            ? implode(',', $this->_custom_selections->columnAliases())
-            : '';
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    "%s is not a valid field on this model, nor a custom selection (%s)",
-                    "event_espresso"
-                ),
-                $query_param,
-                $custom_select_aliases
-            )
-        );
-    }
-
-
-    /**
-     * Removes the * and anything after it from the condition query param key. It is useful to add the * to condition
-     * query param keys (eg, 'OR*', 'EVT_ID') in order for the array keys to still be unique, so that they don't get
-     * overwritten Takes a string like 'Event.EVT_ID*', 'TXN_total**', 'OR*1st', and 'DTT_reg_start*foobar' to
-     * 'Event.EVT_ID', 'TXN_total', 'OR', and 'DTT_reg_start', respectively.
-     *
-     * @param string $condition_query_param_key
-     * @return string
-     */
-    private function _remove_stars_and_anything_after_from_condition_query_param_key($condition_query_param_key)
-    {
-        $pos_of_star = strpos($condition_query_param_key, '*');
-        if ($pos_of_star === false) {
-            return $condition_query_param_key;
-        }
-        $condition_query_param_sans_star = substr($condition_query_param_key, 0, $pos_of_star);
-        return $condition_query_param_sans_star;
-    }
-
-
-    /**
-     * creates the SQL for the operator and the value in a WHERE clause, eg "< 23" or "LIKE '%monkey%'"
-     *
-     * @param mixed      array | string    $op_and_value
-     * @param EE_Model_Field_Base|string $field_obj . If string, should be one of EEM_Base::_valid_wpdb_data_types
-     * @return string
-     * @throws EE_Error
-     */
-    private function _construct_op_and_value($op_and_value, $field_obj)
-    {
-        if (is_array($op_and_value)) {
-            $operator = isset($op_and_value[0]) ? $this->_prepare_operator_for_sql($op_and_value[0]) : null;
-            if (! $operator) {
-                $php_array_like_string = [];
-                foreach ($op_and_value as $key => $value) {
-                    $php_array_like_string[] = "$key=>$value";
-                }
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            "You setup a query parameter like you were going to specify an operator, but didn't. You provided '(%s)', but the operator should be at array key index 0 (eg array('>',32))",
-                            "event_espresso"
-                        ),
-                        implode(",", $php_array_like_string)
-                    )
-                );
-            }
-            $value = isset($op_and_value[1]) ? $op_and_value[1] : null;
-        } else {
-            $operator = '=';
-            $value    = $op_and_value;
-        }
-        // check to see if the value is actually another field
-        if (is_array($op_and_value) && isset($op_and_value[2]) && $op_and_value[2] == true) {
-            return $operator . SP . $this->_deduce_column_name_from_query_param($value);
-        }
-        if (in_array($operator, $this->valid_in_style_operators()) && is_array($value)) {
-            // in this case, the value should be an array, or at least a comma-separated list
-            // it will need to handle a little differently
-            $cleaned_value = $this->_construct_in_value($value, $field_obj);
-            // note: $cleaned_value has already been run through $wpdb->prepare()
-            return $operator . SP . $cleaned_value;
-        }
-        if (in_array($operator, $this->valid_between_style_operators()) && is_array($value)) {
-            // the value should be an array with count of two.
-            if (count($value) !== 2) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            "The '%s' operator must be used with an array of values and there must be exactly TWO values in that array.",
-                            'event_espresso'
-                        ),
-                        "BETWEEN"
-                    )
-                );
-            }
-            $cleaned_value = $this->_construct_between_value($value, $field_obj);
-            return $operator . SP . $cleaned_value;
-        }
-        if (in_array($operator, $this->valid_null_style_operators())) {
-            if ($value !== null) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            "You attempted to give a value  (%s) while using a NULL-style operator (%s). That isn't valid",
-                            "event_espresso"
-                        ),
-                        $value,
-                        $operator
-                    )
-                );
-            }
-            return $operator;
-        }
-        if (in_array($operator, $this->valid_like_style_operators()) && ! is_array($value)) {
-            // if the operator is 'LIKE', we want to allow percent signs (%) and not
-            // remove other junk. So just treat it as a string.
-            return $operator . SP . $this->_wpdb_prepare_using_field($value, '%s');
-        }
-        if (! in_array($operator, $this->valid_in_style_operators()) && ! is_array($value)) {
-            return $operator . SP . $this->_wpdb_prepare_using_field($value, $field_obj);
-        }
-        if (in_array($operator, $this->valid_in_style_operators()) && ! is_array($value)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "Operator '%s' must be used with an array of values, eg 'Registration.REG_ID' => array('%s',array(1,2,3))",
-                        'event_espresso'
-                    ),
-                    $operator,
-                    $operator
-                )
-            );
-        }
-        if (! in_array($operator, $this->valid_in_style_operators()) && is_array($value)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "Operator '%s' must be used with a single value, not an array. Eg 'Registration.REG_ID => array('%s',23))",
-                        'event_espresso'
-                    ),
-                    $operator,
-                    $operator
-                )
-            );
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    "It appears you've provided some totally invalid query parameters. Operator and value were:'%s', which isn't right at all",
-                    "event_espresso"
-                ),
-                http_build_query($op_and_value)
-            )
-        );
-    }
-
-
-    /**
-     * Creates the operands to be used in a BETWEEN query, eg "'2014-12-31 20:23:33' AND '2015-01-23 12:32:54'"
-     *
-     * @param array                      $values
-     * @param EE_Model_Field_Base|string $field_obj if string, it should be the datatype to be used when querying, eg
-     *                                              '%s'
-     * @return string
-     * @throws EE_Error
-     */
-    public function _construct_between_value($values, $field_obj)
-    {
-        $cleaned_values = [];
-        foreach ($values as $value) {
-            $cleaned_values[] = $this->_wpdb_prepare_using_field($value, $field_obj);
-        }
-        return $cleaned_values[0] . " AND " . $cleaned_values[1];
-    }
-
-
-    /**
-     * Takes an array or a comma-separated list of $values and cleans them
-     * according to $data_type using $wpdb->prepare, and then makes the list a
-     * string surrounded by ( and ). Eg, _construct_in_value(array(1,2,3),'%d') would
-     * return '(1,2,3)'; _construct_in_value("1,2,hack",'%d') would return '(1,2,1)' (assuming
-     * I'm right that a string, when interpreted as a digit, becomes a 1. It might become a 0)
-     *
-     * @param mixed                      $values    array or comma-separated string
-     * @param EE_Model_Field_Base|string $field_obj if string, it should be a wpdb data type like '%s', or '%d'
-     * @return string of SQL to follow an 'IN' or 'NOT IN' operator
-     * @throws EE_Error
-     */
-    public function _construct_in_value($values, $field_obj)
-    {
-        $prepped = [];
-        // check if the value is a CSV list
-        if (is_string($values)) {
-            // in which case, turn it into an array
-            $values = explode(',', $values);
-        }
-        // make sure we only have one of each value in the list
-        $values = array_unique($values);
-        foreach ($values as $value) {
-            $prepped[] = $this->_wpdb_prepare_using_field($value, $field_obj);
-        }
-        // we would just LOVE to leave $cleaned_values as an empty array, and return the value as "()",
-        // but unfortunately that's invalid SQL. So instead we return a string which we KNOW will evaluate to be the empty set
-        // which is effectively equivalent to returning "()". We don't return "(0)" because that only works for auto-incrementing columns
-        if (empty($prepped)) {
-            $all_fields  = $this->field_settings();
-            $first_field = reset($all_fields);
-            $main_table  = $this->_get_main_table();
-            $prepped[]   = "SELECT {$first_field->get_table_column()} FROM {$main_table->get_table_name()} WHERE FALSE";
-        }
-        return '(' . implode(',', $prepped) . ')';
-    }
-
-
-    /**
-     * @param mixed                      $value
-     * @param EE_Model_Field_Base|string $field_obj if string it should be a wpdb data type like '%d'
-     * @return false|null|string
-     * @throws EE_Error
-     */
-    private function _wpdb_prepare_using_field($value, $field_obj)
-    {
-        /** @type WPDB $wpdb */
-        global $wpdb;
-        if ($field_obj instanceof EE_Model_Field_Base) {
-            return $wpdb->prepare(
-                $field_obj->get_wpdb_data_type(),
-                $this->_prepare_value_for_use_in_db($value, $field_obj)
-            );
-        } //$field_obj should really just be a data type
-        if (! in_array($field_obj, $this->_valid_wpdb_data_types)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__("%s is not a valid wpdb datatype. Valid ones are %s", "event_espresso"),
-                    $field_obj,
-                    implode(",", $this->_valid_wpdb_data_types)
-                )
-            );
-        }
-        return $wpdb->prepare($field_obj, $value);
-    }
-
-
-    /**
-     * Takes the input parameter and finds the model field that it indicates.
-     *
-     * @param string $query_param_name like Registration.Transaction.TXN_ID, Event.Datetime.start_time, or REG_ID
-     * @return EE_Model_Field_Base
-     * @throws EE_Error
-     */
-    protected function _deduce_field_from_query_param($query_param_name)
-    {
-        // ok, now proceed with deducing which part is the model's name, and which is the field's name
-        // which will help us find the database table and column
-        $query_param_parts = explode(".", $query_param_name);
-        if (empty($query_param_parts)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "_extract_column_name is empty when trying to extract column and table name from %s",
-                        'event_espresso'
-                    ),
-                    $query_param_name
-                )
-            );
-        }
-        $number_of_parts       = count($query_param_parts);
-        $last_query_param_part = $query_param_parts[ count($query_param_parts) - 1 ];
-        if ($number_of_parts === 1) {
-            $field_name = $last_query_param_part;
-            $model_obj  = $this;
-        } else {// $number_of_parts >= 2
-            // the last part is the column name, and there are only 2parts. therefore...
-            $field_name = $last_query_param_part;
-            $model_obj  = $this->get_related_model_obj($query_param_parts[ $number_of_parts - 2 ]);
-        }
-        try {
-            return $model_obj->field_settings_for($field_name);
-        } catch (EE_Error $e) {
-            return null;
-        }
-    }
-
-
-    /**
-     * Given a field's name (ie, a key in $this->field_settings()), uses the EE_Model_Field object to get the table's
-     * alias and column which corresponds to it
-     *
-     * @param string $field_name
-     * @return string
-     * @throws EE_Error
-     */
-    public function _get_qualified_column_for_field($field_name)
-    {
-        $all_fields = $this->field_settings();
-        $field      = isset($all_fields[ $field_name ]) ? $all_fields[ $field_name ] : false;
-        if ($field) {
-            return $field->get_qualified_column();
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    "There is no field titled %s on model %s. Either the query trying to use it is bad, or you need to add it to the list of fields on the model.",
-                    'event_espresso'
-                ),
-                $field_name,
-                get_class($this)
-            )
-        );
-    }
-
-
-    /**
-     * similar to \EEM_Base::_get_qualified_column_for_field() but returns an array with data for ALL fields.
-     * Example usage:
-     * EEM_Ticket::instance()->get_all_wpdb_results(
-     *      array(),
-     *      ARRAY_A,
-     *      EEM_Ticket::instance()->get_qualified_columns_for_all_fields()
-     *  );
-     * is equivalent to
-     *  EEM_Ticket::instance()->get_all_wpdb_results( array(), ARRAY_A, '*' );
-     * and
-     *  EEM_Event::instance()->get_all_wpdb_results(
-     *      array(
-     *          array(
-     *              'Datetime.Ticket.TKT_ID' => array( '<', 100 ),
-     *          ),
-     *          ARRAY_A,
-     *          implode(
-     *              ', ',
-     *              array_merge(
-     *                  EEM_Event::instance()->get_qualified_columns_for_all_fields( '', false ),
-     *                  EEM_Ticket::instance()->get_qualified_columns_for_all_fields( 'Datetime', false )
-     *              )
-     *          )
-     *      )
-     *  );
-     * selects rows from the database, selecting all the event and ticket columns, where the ticket ID is below 100
-     *
-     * @param string $model_relation_chain        the chain of models used to join between the model you want to query
-     *                                            and the one whose fields you are selecting for example: when querying
-     *                                            tickets model and selecting fields from the tickets model you would
-     *                                            leave this parameter empty, because no models are needed to join
-     *                                            between the queried model and the selected one. Likewise when
-     *                                            querying the datetime model and selecting fields from the tickets
-     *                                            model, it would also be left empty, because there is a direct
-     *                                            relation from datetimes to tickets, so no model is needed to join
-     *                                            them together. However, when querying from the event model and
-     *                                            selecting fields from the ticket model, you should provide the string
-     *                                            'Datetime', indicating that the event model must first join to the
-     *                                            datetime model in order to find its relation to ticket model.
-     *                                            Also, when querying from the venue model and selecting fields from
-     *                                            the ticket model, you should provide the string 'Event.Datetime',
-     *                                            indicating you need to join the venue model to the event model,
-     *                                            to the datetime model, in order to find its relation to the ticket
-     *                                            model. This string is used to deduce the prefix that gets added onto
-     *                                            the models' tables qualified columns
-     * @param bool   $return_string               if true, will return a string with qualified column names separated
-     *                                            by ', ' if false, will simply return a numerically indexed array of
-     *                                            qualified column names
-     * @return array|string
-     */
-    public function get_qualified_columns_for_all_fields($model_relation_chain = '', $return_string = true)
-    {
-        $table_prefix      = str_replace('.', '__', $model_relation_chain) . (empty($model_relation_chain) ? '' : '__');
-        $qualified_columns = [];
-        foreach ($this->field_settings() as $field_name => $field) {
-            $qualified_columns[] = $table_prefix . $field->get_qualified_column();
-        }
-        return $return_string ? implode(', ', $qualified_columns) : $qualified_columns;
-    }
-
-
-    /**
-     * constructs the select use on special limit joins
-     * NOTE: for now this has only been tested and will work when the  table alias is for the PRIMARY table. Although
-     * its setup so the select query will be setup on and just doing the special select join off of the primary table
-     * (as that is typically where the limits would be set).
-     *
-     * @param string       $table_alias The table the select is being built for
-     * @param mixed|string $limit       The limit for this select
-     * @return string                The final select join element for the query.
-     * @throws EE_Error
-     * @throws EE_Error
-     */
-    public function _construct_limit_join_select($table_alias, $limit)
-    {
-        $SQL = '';
-        foreach ($this->_tables as $table_obj) {
-            if ($table_obj instanceof EE_Primary_Table) {
-                $SQL .= $table_alias === $table_obj->get_table_alias()
-                    ? $table_obj->get_select_join_limit($limit)
-                    : SP . $table_obj->get_table_name() . " AS " . $table_obj->get_table_alias() . SP;
-            } elseif ($table_obj instanceof EE_Secondary_Table) {
-                $SQL .= $table_alias === $table_obj->get_table_alias()
-                    ? $table_obj->get_select_join_limit_join($limit)
-                    : SP . $table_obj->get_join_sql($table_alias) . SP;
-            }
-        }
-        return $SQL;
-    }
-
-
-    /**
-     * Constructs the internal join if there are multiple tables, or simply the table's name and alias
-     * Eg "wp_post AS Event" or "wp_post AS Event INNER JOIN wp_postmeta Event_Meta ON Event.ID = Event_Meta.post_id"
-     *
-     * @return string SQL
-     * @throws EE_Error
-     */
-    public function _construct_internal_join()
-    {
-        $SQL = $this->_get_main_table()->get_table_sql();
-        $SQL .= $this->_construct_internal_join_to_table_with_alias($this->_get_main_table()->get_table_alias());
-        return $SQL;
-    }
-
-
-    /**
-     * Constructs the SQL for joining all the tables on this model.
-     * Normally $alias should be the primary table's alias, but in cases where
-     * we have already joined to a secondary table (eg, the secondary table has a foreign key and is joined before the
-     * primary table) then we should provide that secondary table's alias. Eg, with $alias being the primary table's
-     * alias, this will construct SQL like:
-     * " INNER JOIN wp_esp_secondary_table AS Secondary_Table ON Primary_Table.pk = Secondary_Table.fk".
-     * With $alias being a secondary table's alias, this will construct SQL like:
-     * " INNER JOIN wp_esp_primary_table AS Primary_Table ON Primary_Table.pk = Secondary_Table.fk".
-     *
-     * @param string $alias_prefixed table alias to join to (this table should already be in the FROM SQL clause)
-     * @return string
-     * @throws EE_Error
-     * @throws EE_Error
-     */
-    public function _construct_internal_join_to_table_with_alias($alias_prefixed)
-    {
-        $SQL               = '';
-        $alias_sans_prefix = EE_Model_Parser::remove_table_alias_model_relation_chain_prefix($alias_prefixed);
-        foreach ($this->_tables as $table_obj) {
-            if ($table_obj instanceof EE_Secondary_Table) {// table is secondary table
-                if ($alias_sans_prefix === $table_obj->get_table_alias()) {
-                    // so we're joining to this table, meaning the table is already in
-                    // the FROM statement, BUT the primary table isn't. So we want
-                    // to add the inverse join sql
-                    $SQL .= $table_obj->get_inverse_join_sql($alias_prefixed);
-                } else {
-                    // just add a regular JOIN to this table from the primary table
-                    $SQL .= $table_obj->get_join_sql($alias_prefixed);
-                }
-            }//if it's a primary table, dont add any SQL. it should already be in the FROM statement
-        }
-        return $SQL;
-    }
-
-
-    /**
-     * Gets an array for storing all the data types on the next-to-be-executed-query.
-     * This should be a growing array of keys being table-columns (eg 'EVT_ID' and 'Event.EVT_ID'), and values being
-     * their data type (eg, '%s', '%d', etc)
-     *
-     * @return array
-     */
-    public function _get_data_types()
-    {
-        $data_types = [];
-        foreach ($this->field_settings() as $field_obj) {
-            // $data_types[$field_obj->get_table_column()] = $field_obj->get_wpdb_data_type();
-            /** @var $field_obj EE_Model_Field_Base */
-            $data_types[ $field_obj->get_qualified_column() ] = $field_obj->get_wpdb_data_type();
-        }
-        return $data_types;
-    }
-
-
-    /**
-     * Gets the model object given the relation's name / model's name (eg, 'Event', 'Registration',etc. Always singular)
-     *
-     * @param string $model_name
-     * @return EEM_Base
-     * @throws EE_Error
-     */
-    public function get_related_model_obj($model_name)
-    {
-        $model_classname = "EEM_" . $model_name;
-        if (! class_exists($model_classname)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "You specified a related model named %s in your query. No such model exists, if it did, it would have the classname %s",
-                        'event_espresso'
-                    ),
-                    $model_name,
-                    $model_classname
-                )
-            );
-        }
-        return call_user_func($model_classname . "::instance");
-    }
-
-
-    /**
-     * Returns the array of EE_ModelRelations for this model.
-     *
-     * @return EE_Model_Relation_Base[]
-     */
-    public function relation_settings()
-    {
-        return $this->_model_relations;
-    }
-
-
-    /**
-     * Gets all related models that this model BELONGS TO. Handy to know sometimes
-     * because without THOSE models, this model probably doesn't have much purpose.
-     * (Eg, without an event, datetimes have little purpose.)
-     *
-     * @return EE_Belongs_To_Relation[]
-     */
-    public function belongs_to_relations()
-    {
-        $belongs_to_relations = [];
-        foreach ($this->relation_settings() as $model_name => $relation_obj) {
-            if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                $belongs_to_relations[ $model_name ] = $relation_obj;
-            }
-        }
-        return $belongs_to_relations;
-    }
-
-
-    /**
-     * Returns the specified EE_Model_Relation, or throws an exception
-     *
-     * @param string $relation_name name of relation, key in $this->_relatedModels
-     * @return EE_Model_Relation_Base
-     * @throws EE_Error
-     */
-    public function related_settings_for($relation_name)
-    {
-        $relatedModels = $this->relation_settings();
-        if (! array_key_exists($relation_name, $relatedModels)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'Cannot get %s related to %s. There is no model relation of that type. There is, however, %s...',
-                        'event_espresso'
-                    ),
-                    $relation_name,
-                    $this->_get_class_name(),
-                    implode(', ', array_keys($relatedModels))
-                )
-            );
-        }
-        return $relatedModels[ $relation_name ];
-    }
-
-
-    /**
-     * A convenience method for getting a specific field's settings, instead of getting all field settings for all
-     * fields
-     *
-     * @param string  $fieldName
-     * @param boolean $include_db_only_fields
-     * @return EE_Model_Field_Base
-     * @throws EE_Error
-     */
-    public function field_settings_for($fieldName, $include_db_only_fields = true)
-    {
-        $fieldSettings = $this->field_settings($include_db_only_fields);
-        if (! array_key_exists($fieldName, $fieldSettings)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__("There is no field/column '%s' on '%s'", 'event_espresso'),
-                    $fieldName,
-                    get_class($this)
-                )
-            );
-        }
-        return $fieldSettings[ $fieldName ];
-    }
-
-
-    /**
-     * Checks if this field exists on this model
-     *
-     * @param string $fieldName a key in the model's _field_settings array
-     * @return boolean
-     */
-    public function has_field($fieldName)
-    {
-        $fieldSettings = $this->field_settings(true);
-        if (isset($fieldSettings[ $fieldName ])) {
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * Returns whether or not this model has a relation to the specified model
-     *
-     * @param string $relation_name possibly one of the keys in the relation_settings array
-     * @return boolean
-     */
-    public function has_relation($relation_name)
-    {
-        $relations = $this->relation_settings();
-        if (isset($relations[ $relation_name ])) {
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * gets the field object of type 'primary_key' from the fieldsSettings attribute.
-     * Eg, on EE_Answer that would be ANS_ID field object
-     *
-     * @param $field_obj
-     * @return boolean
-     */
-    public function is_primary_key_field($field_obj)
-    {
-        return $field_obj instanceof EE_Primary_Key_Field_Base ? true : false;
-    }
-
-
-    /**
-     * gets the field object of type 'primary_key' from the fieldsSettings attribute.
-     * Eg, on EE_Answer that would be ANS_ID field object
-     *
-     * @return EE_Primary_Key_Field_Base
-     * @throws EE_Error
-     */
-    public function get_primary_key_field()
-    {
-        if ($this->_primary_key_field === null) {
-            foreach ($this->field_settings(true) as $field_obj) {
-                if ($this->is_primary_key_field($field_obj)) {
-                    $this->_primary_key_field = $field_obj;
-                    break;
-                }
-            }
-            if (! $this->_primary_key_field instanceof EE_Primary_Key_Field_Base) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__("There is no Primary Key defined on model %s", 'event_espresso'),
-                        get_class($this)
-                    )
-                );
-            }
-        }
-        return $this->_primary_key_field;
-    }
-
-
-    /**
-     * Returns whether or not not there is a primary key on this model.
-     * Internally does some caching.
-     *
-     * @return boolean
-     */
-    public function has_primary_key_field()
-    {
-        if ($this->_has_primary_key_field === null) {
-            try {
-                $this->get_primary_key_field();
-                $this->_has_primary_key_field = true;
-            } catch (EE_Error $e) {
-                $this->_has_primary_key_field = false;
-            }
-        }
-        return $this->_has_primary_key_field;
-    }
-
-
-    /**
-     * Finds the first field of type $field_class_name.
-     *
-     * @param string $field_class_name class name of field that you want to find. Eg, EE_Datetime_Field,
-     *                                 EE_Foreign_Key_Field, etc
-     * @return EE_Model_Field_Base or null if none is found
-     */
-    public function get_a_field_of_type($field_class_name)
-    {
-        foreach ($this->field_settings() as $field) {
-            if ($field instanceof $field_class_name) {
-                return $field;
-            }
-        }
-        return null;
-    }
-
-
-    /**
-     * Gets a foreign key field pointing to model.
-     *
-     * @param string $model_name eg Event, Registration, not EEM_Event
-     * @return EE_Foreign_Key_Field_Base
-     * @throws EE_Error
-     */
-    public function get_foreign_key_to($model_name)
-    {
-        if (! isset($this->_cache_foreign_key_to_fields[ $model_name ])) {
-            foreach ($this->field_settings() as $field) {
-                if (
-                    $field instanceof EE_Foreign_Key_Field_Base
-                    && in_array($model_name, $field->get_model_names_pointed_to())
-                ) {
-                    $this->_cache_foreign_key_to_fields[ $model_name ] = $field;
-                    break;
-                }
-            }
-            if (! isset($this->_cache_foreign_key_to_fields[ $model_name ])) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            "There is no foreign key field pointing to model %s on model %s",
-                            'event_espresso'
-                        ),
-                        $model_name,
-                        get_class($this)
-                    )
-                );
-            }
-        }
-        return $this->_cache_foreign_key_to_fields[ $model_name ];
-    }
-
-
-    /**
-     * Gets the table name (including $wpdb->prefix) for the table alias
-     *
-     * @param string $table_alias eg Event, Event_Meta, Registration, Transaction, but maybe
-     *                            a table alias with a model chain prefix, like 'Venue__Event_Venue___Event_Meta'.
-     *                            Either one works
-     * @return string
-     */
-    public function get_table_for_alias($table_alias)
-    {
-        $table_alias_sans_model_relation_chain_prefix =
-            EE_Model_Parser::remove_table_alias_model_relation_chain_prefix($table_alias);
-        return $this->_tables[ $table_alias_sans_model_relation_chain_prefix ]->get_table_name();
-    }
-
-
-    /**
-     * Returns a flat array of all field son this model, instead of organizing them
-     * by table_alias as they are in the constructor.
-     *
-     * @param bool $include_db_only_fields flag indicating whether or not to include the db-only fields
-     * @return EE_Model_Field_Base[] where the keys are the field's name
-     */
-    public function field_settings($include_db_only_fields = false)
-    {
-        if ($include_db_only_fields) {
-            if ($this->_cached_fields === null) {
-                $this->_cached_fields = [];
-                foreach ($this->_fields as $fields_corresponding_to_table) {
-                    foreach ($fields_corresponding_to_table as $field_name => $field_obj) {
-                        $this->_cached_fields[ $field_name ] = $field_obj;
-                    }
-                }
-            }
-            return $this->_cached_fields;
-        }
-        if ($this->_cached_fields_non_db_only === null) {
-            $this->_cached_fields_non_db_only = [];
-            foreach ($this->_fields as $fields_corresponding_to_table) {
-                foreach ($fields_corresponding_to_table as $field_name => $field_obj) {
-                    /** @var $field_obj EE_Model_Field_Base */
-                    if (! $field_obj->is_db_only_field()) {
-                        $this->_cached_fields_non_db_only[ $field_name ] = $field_obj;
-                    }
-                }
-            }
-        }
-        return $this->_cached_fields_non_db_only;
-    }
-
-
-    /**
-     *        cycle though array of attendees and create objects out of each item
-     *
-     * @access        private
-     * @param array $rows        of results of $wpdb->get_results($query,ARRAY_A)
-     * @return EE_Base_Class[] array keys are primary keys (if there is a primary key on the model. if not,
-     *                           numerically indexed)
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _create_objects($rows = [])
-    {
-        $array_of_objects = [];
-        if (empty($rows)) {
-            return [];
-        }
-        $count_if_model_has_no_primary_key = 0;
-        $has_primary_key                   = $this->has_primary_key_field();
-        $primary_key_field                 = $has_primary_key ? $this->get_primary_key_field() : null;
-        foreach ((array) $rows as $row) {
-            if (empty($row)) {
-                // wp did its weird thing where it returns an array like array(0=>null), which is totally not helpful...
-                return [];
-            }
-            // check if we've already set this object in the results array,
-            // in which case there's no need to process it further (again)
-            if ($has_primary_key) {
-                $table_pk_value = $this->_get_column_value_with_table_alias_or_not(
-                    $row,
-                    $primary_key_field->get_qualified_column(),
-                    $primary_key_field->get_table_column()
-                );
-                if ($table_pk_value && isset($array_of_objects[ $table_pk_value ])) {
-                    continue;
-                }
-            }
-            $classInstance = $this->instantiate_class_from_array_or_object($row);
-            if (! $classInstance) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__('Could not create instance of class %s from row %s', 'event_espresso'),
-                        $this->get_this_model_name(),
-                        http_build_query($row)
-                    )
-                );
-            }
-            // set the timezone on the instantiated objects
-            $classInstance->set_timezone($this->_timezone);
-            // make sure if there is any timezone setting present that we set the timezone for the object
-            $key                      = $has_primary_key ? $classInstance->ID() : $count_if_model_has_no_primary_key++;
-            $array_of_objects[ $key ] = $classInstance;
-            // also, for all the relations of type BelongsTo, see if we can cache
-            // those related models
-            // (we could do this for other relations too, but if there are conditions
-            // that filtered out some fo the results, then we'd be caching an incomplete set
-            // so it requires a little more thought than just caching them immediately...)
-            foreach ($this->_model_relations as $modelName => $relation_obj) {
-                if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                    // check if this model's INFO is present. If so, cache it on the model
-                    $other_model           = $relation_obj->get_other_model();
-                    $other_model_obj_maybe = $other_model->instantiate_class_from_array_or_object($row);
-                    // if we managed to make a model object from the results, cache it on the main model object
-                    if ($other_model_obj_maybe) {
-                        // set timezone on these other model objects if they are present
-                        $other_model_obj_maybe->set_timezone($this->_timezone);
-                        $classInstance->cache($modelName, $other_model_obj_maybe);
-                    }
-                }
-            }
-            // also, if this was a custom select query, let's see if there are any results for the custom select fields
-            // and add them to the object as well.  We'll convert according to the set data_type if there's any set for
-            // the field in the CustomSelects object
-            if ($this->_custom_selections instanceof CustomSelects) {
-                $classInstance->setCustomSelectsValues(
-                    $this->getValuesForCustomSelectAliasesFromResults($row)
-                );
-            }
-        }
-        return $array_of_objects;
-    }
-
-
-    /**
-     * This will parse a given row of results from the db and see if any keys in the results match an alias within the
-     * current CustomSelects object. This will be used to build an array of values indexed by those keys.
-     *
-     * @param array $db_results_row
-     * @return array
-     */
-    protected function getValuesForCustomSelectAliasesFromResults(array $db_results_row)
-    {
-        $results = [];
-        if ($this->_custom_selections instanceof CustomSelects) {
-            foreach ($this->_custom_selections->columnAliases() as $alias) {
-                if (isset($db_results_row[ $alias ])) {
-                    $results[ $alias ] = $this->convertValueToDataType(
-                        $db_results_row[ $alias ],
-                        $this->_custom_selections->getDataTypeForAlias($alias)
-                    );
-                }
-            }
-        }
-        return $results;
-    }
-
-
-    /**
-     * This will set the value for the given alias
-     *
-     * @param string $value
-     * @param string $datatype (one of %d, %s, %f)
-     * @return int|string|float (int for %d, string for %s, float for %f)
-     */
-    protected function convertValueToDataType($value, $datatype)
-    {
-        switch ($datatype) {
-            case '%f':
-                return (float) $value;
-            case '%d':
-                return (int) $value;
-            default:
-                return (string) $value;
-        }
-    }
-
-
-    /**
-     * The purpose of this method is to allow us to create a model object that is not in the db that holds default
-     * values. A typical example of where this is used is when creating a new item and the initial load of a form.  We
-     * dont' necessarily want to test for if the object is present but just assume it is BUT load the defaults from the
-     * object (as set in the model_field!).
-     *
-     * @return EE_Base_Class single EE_Base_Class object with default values for the properties.
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function create_default_object()
-    {
-        $this_model_fields_and_values = [];
-        // setup the row using default values;
-        foreach ($this->field_settings() as $field_name => $field_obj) {
-            $this_model_fields_and_values[ $field_name ] = $field_obj->get_default_value();
-        }
-        $className     = $this->_get_class_name();
-        return EE_Registry::instance()->load_class($className, [$this_model_fields_and_values], false, false);
-    }
-
-
-    /**
-     * @param mixed $cols_n_values either an array of where each key is the name of a field, and the value is its value
-     *                             or an stdClass where each property is the name of a column,
-     * @return EE_Base_Class
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function instantiate_class_from_array_or_object($cols_n_values)
-    {
-        if (! is_array($cols_n_values) && is_object($cols_n_values)) {
-            $cols_n_values = get_object_vars($cols_n_values);
-        }
-        $primary_key = null;
-        // make sure the array only has keys that are fields/columns on this model
-        $this_model_fields_n_values = $this->_deduce_fields_n_values_from_cols_n_values($cols_n_values);
-        if ($this->has_primary_key_field() && isset($this_model_fields_n_values[ $this->primary_key_name() ])) {
-            $primary_key = $this_model_fields_n_values[ $this->primary_key_name() ];
-        }
-        $className = $this->_get_class_name();
-        // check we actually found results that we can use to build our model object
-        // if not, return null
-        if ($this->has_primary_key_field()) {
-            if (empty($this_model_fields_n_values[ $this->primary_key_name() ])) {
-                return null;
-            }
-        } elseif ($this->unique_indexes()) {
-            $first_column = reset($this_model_fields_n_values);
-            if (empty($first_column)) {
-                return null;
-            }
-        }
-        // if there is no primary key or the object doesn't already exist in the entity map, then create a new instance
-        if ($primary_key) {
-            $classInstance = $this->get_from_entity_map($primary_key);
-            if (! $classInstance) {
-                $classInstance = EE_Registry::instance()
-                                            ->load_class(
-                                                $className,
-                                                [$this_model_fields_n_values, $this->_timezone],
-                                                true,
-                                                false
-                                            );
-                // add this new object to the entity map
-                $classInstance = $this->add_to_entity_map($classInstance);
-            }
-        } else {
-            $classInstance = EE_Registry::instance()
-                                        ->load_class(
-                                            $className,
-                                            [$this_model_fields_n_values, $this->_timezone],
-                                            true,
-                                            false
-                                        );
-        }
-        return $classInstance;
-    }
-
-
-    /**
-     * Gets the model object from the  entity map if it exists
-     *
-     * @param int|string $id the ID of the model object
-     * @return EE_Base_Class
-     */
-    public function get_from_entity_map($id)
-    {
-        return isset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ])
-            ? $this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ] : null;
-    }
-
-
-    /**
-     * add_to_entity_map
-     * Adds the object to the model's entity mappings
-     *        Effectively tells the models "Hey, this model object is the most up-to-date representation of the data,
-     *        and for the remainder of the request, it's even more up-to-date than what's in the database.
-     *        So, if the database doesn't agree with what's in the entity mapper, ignore the database"
-     *        If the database gets updated directly and you want the entity mapper to reflect that change,
-     *        then this method should be called immediately after the update query
-     * Note: The map is indexed by whatever the current blog id is set (via EEM_Base::$_model_query_blog_id).  This is
-     * so on multisite, the entity map is specific to the query being done for a specific site.
-     *
-     * @param EE_Base_Class $object
-     * @return EE_Base_Class
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function add_to_entity_map(EE_Base_Class $object)
-    {
-        $className = $this->_get_class_name();
-        if (! $object instanceof $className) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__("You tried adding a %s to a mapping of %ss", "event_espresso"),
-                    is_object($object) ? get_class($object) : $object,
-                    $className
-                )
-            );
-        }
-        /** @var $object EE_Base_Class */
-        if (! $object->ID()) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "You tried storing a model object with NO ID in the %s entity mapper.",
-                        "event_espresso"
-                    ),
-                    get_class($this)
-                )
-            );
-        }
-        // double check it's not already there
-        $classInstance = $this->get_from_entity_map($object->ID());
-        if ($classInstance) {
-            return $classInstance;
-        }
-        $this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $object->ID() ] = $object;
-        return $object;
-    }
-
-
-    /**
-     * if a valid identifier is provided, then that entity is unset from the entity map,
-     * if no identifier is provided, then the entire entity map is emptied
-     *
-     * @param int|string $id the ID of the model object
-     * @return boolean
-     */
-    public function clear_entity_map($id = null)
-    {
-        if (empty($id)) {
-            $this->_entity_map[ EEM_Base::$_model_query_blog_id ] = [];
-            return true;
-        }
-        if (isset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ])) {
-            unset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ]);
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * Public wrapper for _deduce_fields_n_values_from_cols_n_values.
-     * Given an array where keys are column (or column alias) names and values,
-     * returns an array of their corresponding field names and database values
-     *
-     * @param array $cols_n_values
-     * @return array
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function deduce_fields_n_values_from_cols_n_values(array $cols_n_values): array
-    {
-        return $this->_deduce_fields_n_values_from_cols_n_values($cols_n_values);
-    }
-
-
-    /**
-     * _deduce_fields_n_values_from_cols_n_values
-     * Given an array where keys are column (or column alias) names and values,
-     * returns an array of their corresponding field names and database values
-     *
-     * @param array|stdClass $cols_n_values
-     * @return array
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _deduce_fields_n_values_from_cols_n_values($cols_n_values): array
-    {
-        if ($cols_n_values instanceof stdClass) {
-            $cols_n_values = get_object_vars($cols_n_values);
-        }
-        $this_model_fields_n_values = [];
-        foreach ($this->get_tables() as $table_alias => $table_obj) {
-            $table_pk_value = $this->_get_column_value_with_table_alias_or_not(
-                $cols_n_values,
-                $table_obj->get_fully_qualified_pk_column(),
-                $table_obj->get_pk_column()
-            );
-            // there is a primary key on this table and its not set. Use defaults for all its columns
-            if ($table_pk_value === null && $table_obj->get_pk_column()) {
-                foreach ($this->_get_fields_for_table($table_alias) as $field_name => $field_obj) {
-                    if (! $field_obj->is_db_only_field()) {
-                        // prepare field as if its coming from db
-                        $prepared_value                            =
-                            $field_obj->prepare_for_set($field_obj->get_default_value());
-                        $this_model_fields_n_values[ $field_name ] = $field_obj->prepare_for_use_in_db($prepared_value);
-                    }
-                }
-            } else {
-                // the table's rows existed. Use their values
-                foreach ($this->_get_fields_for_table($table_alias) as $field_name => $field_obj) {
-                    if (! $field_obj->is_db_only_field()) {
-                        $this_model_fields_n_values[ $field_name ] = $this->_get_column_value_with_table_alias_or_not(
-                            $cols_n_values,
-                            $field_obj->get_qualified_column(),
-                            $field_obj->get_table_column()
-                        );
-                    }
-                }
-            }
-        }
-        return $this_model_fields_n_values;
-    }
-
-
-    /**
-     * @param $cols_n_values
-     * @param $qualified_column
-     * @param $regular_column
-     * @return null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _get_column_value_with_table_alias_or_not($cols_n_values, $qualified_column, $regular_column)
-    {
-        $value = null;
-        // ask the field what it think it's table_name.column_name should be, and call it the "qualified column"
-        // does the field on the model relate to this column retrieved from the db?
-        // or is it a db-only field? (not relating to the model)
-        if (isset($cols_n_values[ $qualified_column ])) {
-            $value = $cols_n_values[ $qualified_column ];
-        } elseif (isset($cols_n_values[ $regular_column ])) {
-            $value = $cols_n_values[ $regular_column ];
-        } elseif (! empty($this->foreign_key_aliases)) {
-            // no PK?  ok check if there is a foreign key alias set for this table
-            // then check if that alias exists in the incoming data
-            // AND that the actual PK the $FK_alias represents matches the $qualified_column (full PK)
-            foreach ($this->foreign_key_aliases as $FK_alias => $PK_column) {
-                if ($PK_column === $qualified_column && isset($cols_n_values[ $FK_alias ])) {
-                    $value = $cols_n_values[ $FK_alias ];
-                    [$pk_class] = explode('.', $PK_column);
-                    $pk_model_name = "EEM_{$pk_class}";
-                    /** @var EEM_Base $pk_model */
-                    $pk_model = EE_Registry::instance()->load_model($pk_model_name);
-                    if ($pk_model instanceof EEM_Base) {
-                        // make sure object is pulled from db and added to entity map
-                        $pk_model->get_one_by_ID($value);
-                    }
-                    break;
-                }
-            }
-        }
-        return $value;
-    }
-
-
-    /**
-     * refresh_entity_map_from_db
-     * Makes sure the model object in the entity map at $id assumes the values
-     * of the database (opposite of EE_base_Class::save())
-     *
-     * @param int|string $id
-     * @return EE_Base_Class|EE_Soft_Delete_Base_Class|mixed|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function refresh_entity_map_from_db($id)
-    {
-        $obj_in_map = $this->get_from_entity_map($id);
-        if ($obj_in_map) {
-            $wpdb_results = $this->_get_all_wpdb_results(
-                [[$this->get_primary_key_field()->get_name() => $id], 'limit' => 1]
-            );
-            if ($wpdb_results && is_array($wpdb_results)) {
-                $one_row = reset($wpdb_results);
-                foreach ($this->_deduce_fields_n_values_from_cols_n_values($one_row) as $field_name => $db_value) {
-                    $obj_in_map->set_from_db($field_name, $db_value);
-                }
-                // clear the cache of related model objects
-                foreach ($this->relation_settings() as $relation_name => $relation_obj) {
-                    $obj_in_map->clear_cache($relation_name, null, true);
-                }
-            }
-            $this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ] = $obj_in_map;
-            return $obj_in_map;
-        }
-        return $this->get_one_by_ID($id);
-    }
-
-
-    /**
-     * refresh_entity_map_with
-     * Leaves the entry in the entity map alone, but updates it to match the provided
-     * $replacing_model_obj (which we assume to be its equivalent but somehow NOT in the entity map).
-     * This is useful if you have a model object you want to make authoritative over what's in the entity map currently.
-     * Note: The old $replacing_model_obj should now be destroyed as it's now un-authoritative
-     *
-     * @param int|string    $id
-     * @param EE_Base_Class $replacing_model_obj
-     * @return EE_Base_Class
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function refresh_entity_map_with($id, $replacing_model_obj)
-    {
-        $obj_in_map = $this->get_from_entity_map($id);
-        if ($obj_in_map) {
-            if ($replacing_model_obj instanceof EE_Base_Class) {
-                foreach ($replacing_model_obj->model_field_array() as $field_name => $value) {
-                    $obj_in_map->set($field_name, $value);
-                }
-                // make the model object in the entity map's cache match the $replacing_model_obj
-                foreach ($this->relation_settings() as $relation_name => $relation_obj) {
-                    $obj_in_map->clear_cache($relation_name, null, true);
-                    foreach ($replacing_model_obj->get_all_from_cache($relation_name) as $cache_id => $cached_obj) {
-                        $obj_in_map->cache($relation_name, $cached_obj, $cache_id);
-                    }
-                }
-            }
-            return $obj_in_map;
-        }
-        $this->add_to_entity_map($replacing_model_obj);
-        return $replacing_model_obj;
-    }
-
-
-    /**
-     * Gets the EE class that corresponds to this model. Eg, for EEM_Answer that
-     * would be EE_Answer.To import that class, you'd just add ".class.php" to the name, like so
-     * require_once($this->_getClassName().".class.php");
-     *
-     * @return string
-     */
-    private function _get_class_name()
-    {
-        return "EE_" . $this->get_this_model_name();
-    }
-
-
-    /**
-     * Get the name of the items this model represents, for the quantity specified. Eg,
-     * if $quantity==1, on EEM_Event, it would 'Event' (internationalized), otherwise
-     * it would be 'Events'.
-     *
-     * @param int|float|null $quantity
-     * @return string
-     */
-    public function item_name($quantity = 1): string
-    {
-        $quantity = floor($quantity);
-        return apply_filters(
-            'FHEE__EEM_Base__item_name__plural_or_singular',
-            $quantity > 1 ? $this->plural_item : $this->singular_item,
-            $quantity,
-            $this->plural_item,
-            $this->singular_item
-        );
-    }
-
-
-    /**
-     * Very handy general function to allow for plugins to extend any child of EE_TempBase.
-     * If a method is called on a child of EE_TempBase that doesn't exist, this function is called
-     * (http://www.garfieldtech.com/blog/php-magic-call) and passed the method's name and arguments. Instead of
-     * requiring a plugin to extend the EE_TempBase (which works fine is there's only 1 plugin, but when will that
-     * happen?) they can add a hook onto 'filters_hook_espresso__{className}__{methodName}' (eg,
-     * filters_hook_espresso__EE_Answer__my_great_function) and accepts 2 arguments: the object on which the function
-     * was called, and an array of the original arguments passed to the function. Whatever their callback function
-     * returns will be returned by this function. Example: in functions.php (or in a plugin):
-     * add_filter('FHEE__EE_Answer__my_callback','my_callback',10,3); function
-     * my_callback($previousReturnValue,EE_TempBase $object,$argsArray){
-     * $returnString= "you called my_callback! and passed args:".implode(",",$argsArray);
-     *        return $previousReturnValue.$returnString;
-     * }
-     * require('EEM_Answer.model.php');
-     * echo EEM_Answer::instance()->my_callback('monkeys',100);
-     * // will output "you called my_callback! and passed args:monkeys,100"
-     *
-     * @param string $methodName name of method which was called on a child of EE_TempBase, but which
-     * @param array  $args       array of original arguments passed to the function
-     * @return mixed whatever the plugin which calls add_filter decides
-     * @throws EE_Error
-     */
-    public function __call($methodName, $args)
-    {
-        $className = get_class($this);
-        $tagName   = "FHEE__{$className}__{$methodName}";
-        if (! has_filter($tagName)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'Method %1$s on model %2$s does not exist! You can create one with the following code in functions.php or in a plugin: %4$s function my_callback(%4$s \$previousReturnValue, EEM_Base \$object\ $argsArray=NULL ){%4$s     /*function body*/%4$s      return \$whatever;%4$s }%4$s add_filter( \'%3$s\', \'my_callback\', 10, 3 );',
-                        'event_espresso'
-                    ),
-                    $methodName,
-                    $className,
-                    $tagName,
-                    '<br />'
-                )
-            );
-        }
-        return apply_filters($tagName, null, $this, $args);
-    }
-
-
-    /**
-     * Ensures $base_class_obj_or_id is of the EE_Base_Class child that corresponds ot this model.
-     * If not, assumes its an ID, and uses $this->get_one_by_ID() to get the EE_Base_Class.
-     *
-     * @param EE_Base_Class|string|int $base_class_obj_or_id either:
-     *                                                       the EE_Base_Class object that corresponds to this Model,
-     *                                                       the object's class name
-     *                                                       or object's ID
-     * @param boolean                  $ensure_is_in_db      if set, we will also verify this model object
-     *                                                       exists in the database. If it does not, we add it
-     * @return EE_Base_Class
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function ensure_is_obj($base_class_obj_or_id, $ensure_is_in_db = false)
-    {
-        $className = $this->_get_class_name();
-        if ($base_class_obj_or_id instanceof $className) {
-            $model_object = $base_class_obj_or_id;
-        } else {
-            $primary_key_field = $this->get_primary_key_field();
-            if (
-                $primary_key_field instanceof EE_Primary_Key_Int_Field
-                && (
-                    is_int($base_class_obj_or_id)
-                    || is_string($base_class_obj_or_id)
-                )
-            ) {
-                // assume it's an ID.
-                // either a proper integer or a string representing an integer (eg "101" instead of 101)
-                $model_object = $this->get_one_by_ID($base_class_obj_or_id);
-            } elseif (
-                $primary_key_field instanceof EE_Primary_Key_String_Field
-                && is_string($base_class_obj_or_id)
-            ) {
-                // assume its a string representation of the object
-                $model_object = $this->get_one_by_ID($base_class_obj_or_id);
-            } else {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            "'%s' is neither an object of type %s, nor an ID! Its full value is '%s'",
-                            'event_espresso'
-                        ),
-                        $base_class_obj_or_id,
-                        $this->_get_class_name(),
-                        print_r($base_class_obj_or_id, true)
-                    )
-                );
-            }
-        }
-        if ($ensure_is_in_db && $model_object->ID() !== null) {
-            $model_object->save();
-        }
-        return $model_object;
-    }
-
-
-    /**
-     * Similar to ensure_is_obj(), this method makes sure $base_class_obj_or_id
-     * is a value of the this model's primary key. If it's an EE_Base_Class child,
-     * returns it ID.
-     *
-     * @param EE_Base_Class|int|string $base_class_obj_or_id
-     * @return int|string depending on the type of this model object's ID
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function ensure_is_ID($base_class_obj_or_id)
-    {
-        $className = $this->_get_class_name();
-        if ($base_class_obj_or_id instanceof $className) {
-            /** @var $base_class_obj_or_id EE_Base_Class */
-            $id = $base_class_obj_or_id->ID();
-        } elseif (is_int($base_class_obj_or_id)) {
-            // assume it's an ID
-            $id = $base_class_obj_or_id;
-        } elseif (is_string($base_class_obj_or_id)) {
-            // assume its a string representation of the object
-            $id = $base_class_obj_or_id;
-        } else {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "'%s' is neither an object of type %s, nor an ID! Its full value is '%s'",
-                        'event_espresso'
-                    ),
-                    $base_class_obj_or_id,
-                    $this->_get_class_name(),
-                    print_r($base_class_obj_or_id, true)
-                )
-            );
-        }
-        return $id;
-    }
-
-
-    /**
-     * Sets whether the values passed to the model (eg, values in WHERE, values in INSERT, UPDATE, etc)
-     * have already been ran through the appropriate model field's prepare_for_use_in_db method. IE, they have
-     * been sanitized and converted into the appropriate domain.
-     * Usually the only place you'll want to change the default (which is to assume values have NOT been sanitized by
-     * the model object/model field) is when making a method call from WITHIN a model object, which has direct access
-     * to its sanitized values. Note: after changing this setting, you should set it back to its previous value (using
-     * get_assumption_concerning_values_already_prepared_by_model_object()) eg.
-     * $EVT = EEM_Event::instance(); $old_setting =
-     * $EVT->get_assumption_concerning_values_already_prepared_by_model_object();
-     * $EVT->assume_values_already_prepared_by_model_object(true);
-     * $EVT->update(array('foo'=>'bar'),array(array('foo'=>'monkey')));
-     * $EVT->assume_values_already_prepared_by_model_object($old_setting);
-     *
-     * @param int $values_already_prepared like one of the constants on EEM_Base
-     * @return void
-     */
-    public function assume_values_already_prepared_by_model_object(
-        $values_already_prepared = self::not_prepared_by_model_object
-    ) {
-        $this->_values_already_prepared_by_model_object = $values_already_prepared;
-    }
-
-
-    /**
-     * Read comments for assume_values_already_prepared_by_model_object()
-     *
-     * @return int
-     */
-    public function get_assumption_concerning_values_already_prepared_by_model_object()
-    {
-        return $this->_values_already_prepared_by_model_object;
-    }
-
-
-    /**
-     * Gets all the indexes on this model
-     *
-     * @return EE_Index[]
-     */
-    public function indexes()
-    {
-        return $this->_indexes;
-    }
-
-
-    /**
-     * Gets all the Unique Indexes on this model
-     *
-     * @return EE_Unique_Index[]
-     */
-    public function unique_indexes()
-    {
-        $unique_indexes = [];
-        foreach ($this->_indexes as $name => $index) {
-            if ($index instanceof EE_Unique_Index) {
-                $unique_indexes [ $name ] = $index;
-            }
-        }
-        return $unique_indexes;
-    }
-
-
-    /**
-     * Gets all the fields which, when combined, make the primary key.
-     * This is usually just an array with 1 element (the primary key), but in cases
-     * where there is no primary key, it's a combination of fields as defined
-     * on a primary index
-     *
-     * @return EE_Model_Field_Base[] indexed by the field's name
-     * @throws EE_Error
-     */
-    public function get_combined_primary_key_fields()
-    {
-        foreach ($this->indexes() as $index) {
-            if ($index instanceof EE_Primary_Key_Index) {
-                return $index->fields();
-            }
-        }
-        return [$this->primary_key_name() => $this->get_primary_key_field()];
-    }
-
-
-    /**
-     * Used to build a primary key string (when the model has no primary key),
-     * which can be used a unique string to identify this model object.
-     *
-     * @param array $fields_n_values keys are field names, values are their values.
-     *                               Note: if you have results from `EEM_Base::get_all_wpdb_results()`, you need to
-     *                               run it through `EEM_Base::deduce_fields_n_values_from_cols_n_values()`
-     *                               before passing it to this function (that will convert it from columns-n-values
-     *                               to field-names-n-values).
-     * @return string
-     * @throws EE_Error
-     */
-    public function get_index_primary_key_string($fields_n_values)
-    {
-        $cols_n_values_for_primary_key_index = array_intersect_key(
-            $fields_n_values,
-            $this->get_combined_primary_key_fields()
-        );
-        return http_build_query($cols_n_values_for_primary_key_index);
-    }
-
-
-    /**
-     * Gets the field values from the primary key string
-     *
-     * @param string $index_primary_key_string
-     * @return null|array
-     * @throws EE_Error
-     * @see EEM_Base::get_combined_primary_key_fields() and EEM_Base::get_index_primary_key_string()
-     */
-    public function parse_index_primary_key_string($index_primary_key_string)
-    {
-        $key_fields = $this->get_combined_primary_key_fields();
-        // check all of them are in the $id
-        $key_vals_in_combined_pk = [];
-        parse_str($index_primary_key_string, $key_vals_in_combined_pk);
-        foreach ($key_fields as $key_field_name => $field_obj) {
-            if (! isset($key_vals_in_combined_pk[ $key_field_name ])) {
-                return null;
-            }
-        }
-        return $key_vals_in_combined_pk;
-    }
-
-
-    /**
-     * verifies that an array of key-value pairs for model fields has a key
-     * for each field comprising the primary key index
-     *
-     * @param array $key_vals
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function has_all_combined_primary_key_fields($key_vals)
-    {
-        $keys_it_should_have = array_keys($this->get_combined_primary_key_fields());
-        foreach ($keys_it_should_have as $key) {
-            if (! isset($key_vals[ $key ])) {
-                return false;
-            }
-        }
-        return true;
-    }
-
-
-    /**
-     * Finds all model objects in the DB that appear to be a copy of $model_object_or_attributes_array.
-     * We consider something to be a copy if all the attributes match (except the ID, of course).
-     *
-     * @param array|EE_Base_Class $model_object_or_attributes_array If its an array, it's field-value pairs
-     * @param array               $query_params                     @see
-     *                                                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @return EE_Base_Class[] Array keys are object IDs (if there is a primary key on the model. if not, numerically
-     *                                                              indexed)
-     */
-    public function get_all_copies($model_object_or_attributes_array, $query_params = [])
-    {
-        if ($model_object_or_attributes_array instanceof EE_Base_Class) {
-            $attributes_array = $model_object_or_attributes_array->model_field_array();
-        } elseif (is_array($model_object_or_attributes_array)) {
-            $attributes_array = $model_object_or_attributes_array;
-        } else {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "get_all_copies should be provided with either a model object or an array of field-value-pairs, but was given %s",
-                        "event_espresso"
-                    ),
-                    $model_object_or_attributes_array
-                )
-            );
-        }
-        // even copies obviously won't have the same ID, so remove the primary key
-        // from the WHERE conditions for finding copies (if there is a primary key, of course)
-        if ($this->has_primary_key_field() && isset($attributes_array[ $this->primary_key_name() ])) {
-            unset($attributes_array[ $this->primary_key_name() ]);
-        }
-        if (isset($query_params[0])) {
-            $query_params[0] = array_merge($attributes_array, $query_params);
-        } else {
-            $query_params[0] = $attributes_array;
-        }
-        return $this->get_all($query_params);
-    }
-
-
-    /**
-     * Gets the first copy we find. See get_all_copies for more details
-     *
-     * @param mixed EE_Base_Class | array        $model_object_or_attributes_array
-     * @param array $query_params
-     * @return EE_Base_Class
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_one_copy($model_object_or_attributes_array, $query_params = [])
-    {
-        if (! is_array($query_params)) {
-            EE_Error::doing_it_wrong(
-                'EEM_Base::get_one_copy',
-                sprintf(
-                    esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
-                    gettype($query_params)
-                ),
-                '4.6.0'
-            );
-            $query_params = [];
-        }
-        $query_params['limit'] = 1;
-        $copies                = $this->get_all_copies($model_object_or_attributes_array, $query_params);
-        if (is_array($copies)) {
-            return array_shift($copies);
-        }
-        return null;
-    }
-
-
-    /**
-     * Updates the item with the specified id. Ignores default query parameters because
-     * we have specified the ID, and its assumed we KNOW what we're doing
-     *
-     * @param array      $fields_n_values keys are field names, values are their new values
-     * @param int|string $id              the value of the primary key to update
-     * @return int number of rows updated
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function update_by_ID($fields_n_values, $id)
-    {
-        $query_params = [
-            0                          => [$this->get_primary_key_field()->get_name() => $id],
-            'default_where_conditions' => EEM_Base::default_where_conditions_others_only,
-        ];
-        return $this->update($fields_n_values, $query_params);
-    }
-
-
-    /**
-     * Changes an operator which was supplied to the models into one usable in SQL
-     *
-     * @param string $operator_supplied
-     * @return string an operator which can be used in SQL
-     * @throws EE_Error
-     */
-    private function _prepare_operator_for_sql($operator_supplied)
-    {
-        $sql_operator = $this->_valid_operators[ $operator_supplied ] ?? null;
-        if ($sql_operator) {
-            return $sql_operator;
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    "The operator '%s' is not in the list of valid operators: %s",
-                    "event_espresso"
-                ),
-                $operator_supplied,
-                implode(",", array_keys($this->_valid_operators))
-            )
-        );
-    }
-
-
-    /**
-     * Gets the valid operators
-     *
-     * @return array keys are accepted strings, values are the SQL they are converted to
-     */
-    public function valid_operators()
-    {
-        return $this->_valid_operators;
-    }
-
-
-    /**
-     * Gets the between-style operators (take 2 arguments).
-     *
-     * @return array keys are accepted strings, values are the SQL they are converted to
-     */
-    public function valid_between_style_operators()
-    {
-        return array_intersect(
-            $this->valid_operators(),
-            $this->_between_style_operators
-        );
-    }
-
-
-    /**
-     * Gets the "like"-style operators (take a single argument, but it may contain wildcards)
-     *
-     * @return array keys are accepted strings, values are the SQL they are converted to
-     */
-    public function valid_like_style_operators()
-    {
-        return array_intersect(
-            $this->valid_operators(),
-            $this->_like_style_operators
-        );
-    }
-
-
-    /**
-     * Gets the "in"-style operators
-     *
-     * @return array keys are accepted strings, values are the SQL they are converted to
-     */
-    public function valid_in_style_operators()
-    {
-        return array_intersect(
-            $this->valid_operators(),
-            $this->_in_style_operators
-        );
-    }
-
-
-    /**
-     * Gets the "null"-style operators (accept no arguments)
-     *
-     * @return array keys are accepted strings, values are the SQL they are converted to
-     */
-    public function valid_null_style_operators()
-    {
-        return array_intersect(
-            $this->valid_operators(),
-            $this->_null_style_operators
-        );
-    }
-
-
-    /**
-     * Gets an array where keys are the primary keys and values are their 'names'
-     * (as determined by the model object's name() function, which is often overridden)
-     *
-     * @param array $query_params like get_all's
-     * @return string[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_all_names($query_params = [])
-    {
-        $objs  = $this->get_all($query_params);
-        $names = [];
-        foreach ($objs as $obj) {
-            $names[ $obj->ID() ] = $obj->name();
-        }
-        return $names;
-    }
-
-
-    /**
-     * Gets an array of primary keys from the model objects. If you acquired the model objects
-     * using EEM_Base::get_all() you don't need to call this (and probably shouldn't because
-     * this is duplicated effort and reduces efficiency) you would be better to use
-     * array_keys() on $model_objects.
-     *
-     * @param \EE_Base_Class[] $model_objects
-     * @param boolean          $filter_out_empty_ids if a model object has an ID of '' or 0, don't bother including it
-     *                                               in the returned array
-     * @return array
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_IDs($model_objects, $filter_out_empty_ids = false)
-    {
-        if (! $this->has_primary_key_field()) {
-            if (WP_DEBUG) {
-                EE_Error::add_error(
-                    esc_html__('Trying to get IDs from a model than has no primary key', 'event_espresso'),
-                    __FILE__,
-                    __FUNCTION__,
-                    __LINE__
-                );
-            }
-        }
-        $IDs = [];
-        foreach ($model_objects as $model_object) {
-            $id = $model_object->ID();
-            if (! $id) {
-                if ($filter_out_empty_ids) {
-                    continue;
-                }
-                if (WP_DEBUG) {
-                    EE_Error::add_error(
-                        esc_html__(
-                            'Called %1$s on a model object that has no ID and so probably hasn\'t been saved to the database',
-                            'event_espresso'
-                        ),
-                        __FILE__,
-                        __FUNCTION__,
-                        __LINE__
-                    );
-                }
-            }
-            $IDs[] = $id;
-        }
-        return $IDs;
-    }
-
-
-    /**
-     * Returns the string used in capabilities relating to this model. If there
-     * are no capabilities that relate to this model returns false
-     *
-     * @return string|false
-     */
-    public function cap_slug()
-    {
-        return apply_filters('FHEE__EEM_Base__cap_slug', $this->_caps_slug, $this);
-    }
-
-
-    /**
-     * Returns the capability-restrictions array (@param string $context
-     *
-     * @return EE_Default_Where_Conditions[] indexed by associated capability
-     * @throws EE_Error
-     * @see EEM_Base::_cap_restrictions).
-     *      If $context is provided (which should be set to one of EEM_Base::valid_cap_contexts())
-     *      only returns the cap restrictions array in that context (ie, the array
-     *      at that key)
-     *
-     */
-    public function cap_restrictions($context = EEM_Base::caps_read)
-    {
-        EEM_Base::verify_is_valid_cap_context($context);
-        // check if we ought to run the restriction generator first
-        if (
-            isset($this->_cap_restriction_generators[ $context ])
-            && $this->_cap_restriction_generators[ $context ] instanceof EE_Restriction_Generator_Base
-            && ! $this->_cap_restriction_generators[ $context ]->has_generated_cap_restrictions()
-        ) {
-            $this->_cap_restrictions[ $context ] = array_merge(
-                $this->_cap_restrictions[ $context ],
-                $this->_cap_restriction_generators[ $context ]->generate_restrictions()
-            );
-        }
-        // and make sure we've finalized the construction of each restriction
-        foreach ($this->_cap_restrictions[ $context ] as $where_conditions_obj) {
-            if ($where_conditions_obj instanceof EE_Default_Where_Conditions) {
-                $where_conditions_obj->_finalize_construct($this);
-            }
-        }
-        return $this->_cap_restrictions[ $context ];
-    }
-
-
-    /**
-     * Indicating whether or not this model thinks its a wp core model
-     *
-     * @return boolean
-     */
-    public function is_wp_core_model()
-    {
-        return $this->_wp_core_model;
-    }
-
-
-    /**
-     * Gets all the caps that are missing which impose a restriction on
-     * queries made in this context
-     *
-     * @param string $context one of EEM_Base::caps_ constants
-     * @return EE_Default_Where_Conditions[] indexed by capability name
-     * @throws EE_Error
-     */
-    public function caps_missing($context = EEM_Base::caps_read)
-    {
-        $missing_caps     = [];
-        $cap_restrictions = $this->cap_restrictions($context);
-        foreach ($cap_restrictions as $cap => $restriction_if_no_cap) {
-            if (
-                ! EE_Capabilities::instance()
-                                 ->current_user_can($cap, $this->get_this_model_name() . '_model_applying_caps')
-            ) {
-                $missing_caps[ $cap ] = $restriction_if_no_cap;
-            }
-        }
-        return $missing_caps;
-    }
-
-
-    /**
-     * Gets the mapping from capability contexts to action strings used in capability names
-     *
-     * @return array keys are one of EEM_Base::valid_cap_contexts(), and values are usually
-     * one of 'read', 'edit', or 'delete'
-     */
-    public function cap_contexts_to_cap_action_map()
-    {
-        return apply_filters(
-            'FHEE__EEM_Base__cap_contexts_to_cap_action_map',
-            $this->_cap_contexts_to_cap_action_map,
-            $this
-        );
-    }
-
-
-    /**
-     * Gets the action string for the specified capability context
-     *
-     * @param string $context
-     * @return string one of EEM_Base::cap_contexts_to_cap_action_map() values
-     * @throws EE_Error
-     */
-    public function cap_action_for_context($context)
-    {
-        $mapping = $this->cap_contexts_to_cap_action_map();
-        if (isset($mapping[ $context ])) {
-            return $mapping[ $context ];
-        }
-        if ($action = apply_filters('FHEE__EEM_Base__cap_action_for_context', null, $this, $mapping, $context)) {
-            return $action;
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    'Cannot find capability restrictions for context "%1$s", allowed values are:%2$s',
-                    'event_espresso'
-                ),
-                $context,
-                implode(',', array_keys($this->cap_contexts_to_cap_action_map()))
-            )
-        );
-    }
-
-
-    /**
-     * Returns all the capability contexts which are valid when querying models
-     *
-     * @return array
-     */
-    public static function valid_cap_contexts()
-    {
-        return apply_filters('FHEE__EEM_Base__valid_cap_contexts', [
-            self::caps_read,
-            self::caps_read_admin,
-            self::caps_edit,
-            self::caps_delete,
-        ]);
-    }
-
-
-    /**
-     * Returns all valid options for 'default_where_conditions'
-     *
-     * @return array
-     */
-    public static function valid_default_where_conditions()
-    {
-        return [
-            EEM_Base::default_where_conditions_all,
-            EEM_Base::default_where_conditions_this_only,
-            EEM_Base::default_where_conditions_others_only,
-            EEM_Base::default_where_conditions_minimum_all,
-            EEM_Base::default_where_conditions_minimum_others,
-            EEM_Base::default_where_conditions_none,
-        ];
-    }
-
-    // public static function default_where_conditions_full
-
-
-    /**
-     * Verifies $context is one of EEM_Base::valid_cap_contexts(), if not it throws an exception
-     *
-     * @param string $context
-     * @return bool
-     * @throws EE_Error
-     */
-    public static function verify_is_valid_cap_context($context)
-    {
-        $valid_cap_contexts = EEM_Base::valid_cap_contexts();
-        if (in_array($context, $valid_cap_contexts)) {
-            return true;
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    'Context "%1$s" passed into model "%2$s" is not a valid context. They are: %3$s',
-                    'event_espresso'
-                ),
-                $context,
-                'EEM_Base',
-                implode(',', $valid_cap_contexts)
-            )
-        );
-    }
-
-
-    /**
-     * Clears all the models field caches. This is only useful when a sub-class
-     * might have added a field or something and these caches might be invalidated
-     */
-    protected function _invalidate_field_caches()
-    {
-        $this->_cache_foreign_key_to_fields = [];
-        $this->_cached_fields               = null;
-        $this->_cached_fields_non_db_only   = null;
-    }
-
-
-    /**
-     * Gets the list of all the where query param keys that relate to logic instead of field names
-     * (eg "and", "or", "not").
-     *
-     * @return array
-     */
-    public function logic_query_param_keys()
-    {
-        return $this->_logic_query_param_keys;
-    }
-
-
-    /**
-     * Determines whether or not the where query param array key is for a logic query param.
-     * Eg 'OR', 'not*', and 'and*because-i-say-so' should all return true, whereas
-     * 'ATT_fname', 'EVT_name*not-you-or-me', and 'ORG_name' should return false
-     *
-     * @param $query_param_key
-     * @return bool
-     */
-    public function is_logic_query_param_key($query_param_key)
-    {
-        foreach ($this->logic_query_param_keys() as $logic_query_param_key) {
-            if (
-                $query_param_key === $logic_query_param_key
-                || strpos($query_param_key, $logic_query_param_key . '*') === 0
-            ) {
-                return true;
-            }
-        }
-        return false;
-    }
-
-
-    /**
-     * Returns true if this model has a password field on it (regardless of whether that password field has any content)
-     *
-     * @return boolean
-     * @since 4.9.74.p
-     */
-    public function hasPassword()
-    {
-        // if we don't yet know if there's a password field, find out and remember it for next time.
-        if ($this->has_password_field === null) {
-            $password_field           = $this->getPasswordField();
-            $this->has_password_field = $password_field instanceof EE_Password_Field ? true : false;
-        }
-        return $this->has_password_field;
-    }
-
-
-    /**
-     * Returns the password field on this model, if there is one
-     *
-     * @return EE_Password_Field|null
-     * @since 4.9.74.p
-     */
-    public function getPasswordField()
-    {
-        // if we definetely already know there is a password field or not (because has_password_field is true or false)
-        // there's no need to search for it. If we don't know yet, then find out
-        if ($this->has_password_field === null && $this->password_field === null) {
-            $this->password_field = $this->get_a_field_of_type('EE_Password_Field');
-        }
-        // don't bother setting has_password_field because that's hasPassword()'s job.
-        return $this->password_field;
-    }
-
-
-    /**
-     * Returns the list of field (as EE_Model_Field_Bases) that are protected by the password
-     *
-     * @return EE_Model_Field_Base[]
-     * @throws EE_Error
-     * @since 4.9.74.p
-     */
-    public function getPasswordProtectedFields()
-    {
-        $password_field = $this->getPasswordField();
-        $fields         = [];
-        if ($password_field instanceof EE_Password_Field) {
-            $field_names = $password_field->protectedFields();
-            foreach ($field_names as $field_name) {
-                $fields[ $field_name ] = $this->field_settings_for($field_name);
-            }
-        }
-        return $fields;
-    }
-
-
-    /**
-     * Checks if the current user can perform the requested action on this model
-     *
-     * @param string              $cap_to_check one of the array keys from _cap_contexts_to_cap_action_map
-     * @param EE_Base_Class|array $model_obj_or_fields_n_values
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws UnexpectedEntityException
-     * @since 4.9.74.p
-     */
-    public function currentUserCan($cap_to_check, $model_obj_or_fields_n_values)
-    {
-        if ($model_obj_or_fields_n_values instanceof EE_Base_Class) {
-            $model_obj_or_fields_n_values = $model_obj_or_fields_n_values->model_field_array();
-        }
-        if (! is_array($model_obj_or_fields_n_values)) {
-            throw new UnexpectedEntityException(
-                $model_obj_or_fields_n_values,
-                'EE_Base_Class',
-                sprintf(
-                    esc_html__(
-                        '%1$s must be passed an `EE_Base_Class or an array of fields names with their values. You passed in something different.',
-                        'event_espresso'
-                    ),
-                    __FUNCTION__
-                )
-            );
-        }
-        return $this->exists(
-            $this->alter_query_params_to_restrict_by_ID(
-                $this->get_index_primary_key_string($model_obj_or_fields_n_values),
-                [
-                    'default_where_conditions' => 'none',
-                    'caps'                     => $cap_to_check,
-                ]
-            )
-        );
-    }
-
-
-    /**
-     * Returns the query param where conditions key to the password affecting this model.
-     * Eg on EEM_Event this would just be "password", on EEM_Datetime this would be "Event.password", etc.
-     *
-     * @return null|string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ModelConfigurationException
-     * @throws ReflectionException
-     * @since 4.9.74.p
-     */
-    public function modelChainAndPassword()
-    {
-        if ($this->model_chain_to_password === null) {
-            throw new ModelConfigurationException(
-                $this,
-                esc_html_x(
-                // @codingStandardsIgnoreStart
-                    'Cannot exclude protected data because the model has not specified which model has the password.',
-                    // @codingStandardsIgnoreEnd
-                    '1: model name',
-                    'event_espresso'
-                )
-            );
-        }
-        if ($this->model_chain_to_password === '') {
-            $model_with_password = $this;
-        } else {
-            if ($pos_of_period = strrpos($this->model_chain_to_password, '.')) {
-                $last_model_in_chain = substr($this->model_chain_to_password, $pos_of_period + 1);
-            } else {
-                $last_model_in_chain = $this->model_chain_to_password;
-            }
-            $model_with_password = EE_Registry::instance()->load_model($last_model_in_chain);
-        }
-
-        $password_field = $model_with_password->getPasswordField();
-        if ($password_field instanceof EE_Password_Field) {
-            $password_field_name = $password_field->get_name();
-        } else {
-            throw new ModelConfigurationException(
-                $this,
-                sprintf(
-                    esc_html_x(
-                        'This model claims related model "%1$s" should have a password field on it, but none was found. The model relation chain is "%2$s"',
-                        '1: model name, 2: special string',
-                        'event_espresso'
-                    ),
-                    $model_with_password->get_this_model_name(),
-                    $this->model_chain_to_password
-                )
-            );
-        }
-        return ($this->model_chain_to_password ? $this->model_chain_to_password . '.' : '') . $password_field_name;
-    }
-
-
-    /**
-     * Returns true if there is a password on a related model which restricts access to some of this model's rows,
-     * or if this model itself has a password affecting access to some of its other fields.
-     *
-     * @return boolean
-     * @since 4.9.74.p
-     */
-    public function restrictedByRelatedModelPassword()
-    {
-        return $this->model_chain_to_password !== null;
-    }
+		}
+		return $null_friendly_where_conditions;
+	}
+
+
+	/**
+	 * Uses the _default_where_conditions_strategy set during __construct() to get
+	 * default where conditions on all get_all, update, and delete queries done by this model.
+	 * Use the same syntax as client code. Eg on the Event model, use array('Event.EVT_post_type'=>'esp_event'),
+	 * NOT array('Event_CPT.post_type'=>'esp_event').
+	 *
+	 * @param string $model_relation_path eg, path from Event to Payment is "Registration.Transaction.Payment."
+	 * @return array @see
+	 *                                    https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @throws EE_Error
+	 * @throws EE_Error
+	 */
+	private function _get_default_where_conditions($model_relation_path = '')
+	{
+		if ($this->_ignore_where_strategy) {
+			return [];
+		}
+		return $this->_default_where_conditions_strategy->get_default_where_conditions($model_relation_path);
+	}
+
+
+	/**
+	 * Uses the _minimum_where_conditions_strategy set during __construct() to get
+	 * minimum where conditions on all get_all, update, and delete queries done by this model.
+	 * Use the same syntax as client code. Eg on the Event model, use array('Event.EVT_post_type'=>'esp_event'),
+	 * NOT array('Event_CPT.post_type'=>'esp_event').
+	 * Similar to _get_default_where_conditions
+	 *
+	 * @param string $model_relation_path eg, path from Event to Payment is "Registration.Transaction.Payment."
+	 * @return array @see
+	 *                                    https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @throws EE_Error
+	 * @throws EE_Error
+	 */
+	protected function _get_minimum_where_conditions($model_relation_path = '')
+	{
+		if ($this->_ignore_where_strategy) {
+			return [];
+		}
+		return $this->_minimum_where_conditions_strategy->get_default_where_conditions($model_relation_path);
+	}
+
+
+	/**
+	 * Creates the string of SQL for the select part of a select query, everything behind SELECT and before FROM.
+	 * Eg, "Event.post_id, Event.post_name,Event_Detail.EVT_ID..."
+	 *
+	 * @param EE_Model_Query_Info_Carrier $model_query_info
+	 * @return string
+	 * @throws EE_Error
+	 */
+	private function _construct_default_select_sql(EE_Model_Query_Info_Carrier $model_query_info)
+	{
+		$selects = $this->_get_columns_to_select_for_this_model();
+		foreach (
+			$model_query_info->get_model_names_included() as $model_relation_chain => $name_of_other_model_included
+		) {
+			$other_model_included = $this->get_related_model_obj($name_of_other_model_included);
+			$other_model_selects  = $other_model_included->_get_columns_to_select_for_this_model($model_relation_chain);
+			foreach ($other_model_selects as $key => $value) {
+				$selects[] = $value;
+			}
+		}
+		return implode(", ", $selects);
+	}
+
+
+	/**
+	 * Gets an array of columns to select for this model, which are necessary for it to create its objects.
+	 * So that's going to be the columns for all the fields on the model
+	 *
+	 * @param string $model_relation_chain like 'Question.Question_Group.Event'
+	 * @return array numerically indexed, values are columns to select and rename, eg "Event.ID AS 'Event.ID'"
+	 */
+	public function _get_columns_to_select_for_this_model($model_relation_chain = '')
+	{
+		$fields                                       = $this->field_settings();
+		$selects                                      = [];
+		$table_alias_with_model_relation_chain_prefix =
+			EE_Model_Parser::extract_table_alias_model_relation_chain_prefix(
+				$model_relation_chain,
+				$this->get_this_model_name()
+			);
+		foreach ($fields as $field_obj) {
+			$selects[] = $table_alias_with_model_relation_chain_prefix
+						 . $field_obj->get_table_alias()
+						 . "."
+						 . $field_obj->get_table_column()
+						 . " AS '"
+						 . $table_alias_with_model_relation_chain_prefix
+						 . $field_obj->get_table_alias()
+						 . "."
+						 . $field_obj->get_table_column()
+						 . "'";
+		}
+		// make sure we are also getting the PKs of each table
+		$tables = $this->get_tables();
+		if (count($tables) > 1) {
+			foreach ($tables as $table_obj) {
+				$qualified_pk_column = $table_alias_with_model_relation_chain_prefix
+									   . $table_obj->get_fully_qualified_pk_column();
+				if (! in_array($qualified_pk_column, $selects)) {
+					$selects[] = "$qualified_pk_column AS '$qualified_pk_column'";
+				}
+			}
+		}
+		return $selects;
+	}
+
+
+	/**
+	 * Given a $query_param like 'Registration.Transaction.TXN_ID', pops off 'Registration.',
+	 * gets the join statement for it; gets the data types for it; and passes the remaining 'Transaction.TXN_ID'
+	 * onto its related Transaction object to do the same. Returns an EE_Join_And_Data_Types object which contains the
+	 * SQL for joining, and the data types
+	 *
+	 * @param null|string                 $original_query_param
+	 * @param string                      $query_param          like Registration.Transaction.TXN_ID
+	 * @param EE_Model_Query_Info_Carrier $passed_in_query_info
+	 * @param string                      $query_param_type     like Registration.Transaction.TXN_ID
+	 *                                                          or 'PAY_ID'. Otherwise, we don't expect there to be a
+	 *                                                          column name. We only want model names, eg 'Event.Venue'
+	 *                                                          or 'Registration's
+	 * @param string                      $original_query_param what it originally was (eg
+	 *                                                          Registration.Transaction.TXN_ID). If null, we assume it
+	 *                                                          matches $query_param
+	 * @return void only modifies the EEM_Related_Model_Info_Carrier passed into it
+	 * @throws EE_Error
+	 */
+	private function _extract_related_model_info_from_query_param(
+		$query_param,
+		EE_Model_Query_Info_Carrier $passed_in_query_info,
+		$query_param_type,
+		$original_query_param = null
+	) {
+		if ($original_query_param === null) {
+			$original_query_param = $query_param;
+		}
+		$query_param = $this->_remove_stars_and_anything_after_from_condition_query_param_key($query_param);
+		// check to see if we have a field on this model
+		$this_model_fields = $this->field_settings(true);
+		if (array_key_exists($query_param, $this_model_fields)) {
+			$field_is_allowed = in_array(
+				$query_param_type,
+				[0, 'where', 'having', 'order_by', 'group_by', 'order', 'custom_selects'],
+				true
+			);
+			if ($field_is_allowed) {
+				return;
+			}
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"Using a field name (%s) on model %s is not allowed on this query param type '%s'. Original query param was %s",
+						"event_espresso"
+					),
+					$query_param,
+					get_class($this),
+					$query_param_type,
+					$original_query_param
+				)
+			);
+		}
+		// check if this is a special logic query param
+		if (in_array($query_param, $this->_logic_query_param_keys, true)) {
+			$operator_is_allowed = in_array($query_param_type, ['where', 'having', 0, 'custom_selects'], true);
+			if ($operator_is_allowed) {
+				return;
+			}
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'Logic query params ("%1$s") are being used incorrectly with the following query param ("%2$s") on model %3$s. %4$sAdditional Info:%4$s%5$s',
+						'event_espresso'
+					),
+					implode('", "', $this->_logic_query_param_keys),
+					$query_param,
+					get_class($this),
+					'<br />',
+					"\t"
+					. ' $passed_in_query_info = <pre>'
+					. print_r($passed_in_query_info, true)
+					. '</pre>'
+					. "\n\t"
+					. ' $query_param_type = '
+					. $query_param_type
+					. "\n\t"
+					. ' $original_query_param = '
+					. $original_query_param
+				)
+			);
+		}
+		// check if it's a custom selection
+		if (
+			$this->_custom_selections instanceof CustomSelects
+			&& in_array($query_param, $this->_custom_selections->columnAliases(), true)
+		) {
+			return;
+		}
+		// check if has a model name at the beginning
+		// and
+		// check if it's a field on a related model
+		if (
+			$this->extractJoinModelFromQueryParams(
+				$passed_in_query_info,
+				$query_param,
+				$original_query_param,
+				$query_param_type
+			)
+		) {
+			return;
+		}
+
+		// ok so $query_param didn't start with a model name
+		// and we previously confirmed it wasn't a logic query param or field on the current model
+		// it's wack, that's what it is
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					"There is no model named '%s' related to %s. Query param type is %s and original query param is %s",
+					"event_espresso"
+				),
+				$query_param,
+				get_class($this),
+				$query_param_type,
+				$original_query_param
+			)
+		);
+	}
+
+
+	/**
+	 * Extracts any possible join model information from the provided possible_join_string.
+	 * This method will read the provided $possible_join_string value and determine if there are any possible model
+	 * join
+	 * parts that should be added to the query.
+	 *
+	 * @param EE_Model_Query_Info_Carrier $query_info_carrier
+	 * @param string                      $possible_join_string  Such as Registration.REG_ID, or Registration
+	 * @param null|string                 $original_query_param
+	 * @param string                      $query_parameter_type  The type for the source of the $possible_join_string
+	 *                                                           ('where', 'order_by', 'group_by', 'custom_selects'
+	 *                                                           etc.)
+	 * @return bool  returns true if a join was added and false if not.
+	 * @throws EE_Error
+	 */
+	private function extractJoinModelFromQueryParams(
+		EE_Model_Query_Info_Carrier $query_info_carrier,
+		$possible_join_string,
+		$original_query_param,
+		$query_parameter_type
+	) {
+		foreach ($this->_model_relations as $valid_related_model_name => $relation_obj) {
+			if (strpos($possible_join_string, $valid_related_model_name . ".") === 0) {
+				$this->_add_join_to_model($valid_related_model_name, $query_info_carrier, $original_query_param);
+				$possible_join_string = substr($possible_join_string, strlen($valid_related_model_name . "."));
+				if ($possible_join_string === '') {
+					// nothing left to $query_param
+					// we should actually end in a field name, not a model like this!
+					throw new EE_Error(
+						sprintf(
+							esc_html__(
+								"Query param '%s' (of type %s on model %s) shouldn't end on a period (.) ",
+								"event_espresso"
+							),
+							$possible_join_string,
+							$query_parameter_type,
+							get_class($this),
+							$valid_related_model_name
+						)
+					);
+				}
+				$related_model_obj = $this->get_related_model_obj($valid_related_model_name);
+				$related_model_obj->_extract_related_model_info_from_query_param(
+					$possible_join_string,
+					$query_info_carrier,
+					$query_parameter_type,
+					$original_query_param
+				);
+				return true;
+			}
+			if ($possible_join_string === $valid_related_model_name) {
+				$this->_add_join_to_model(
+					$valid_related_model_name,
+					$query_info_carrier,
+					$original_query_param
+				);
+				return true;
+			}
+		}
+		return false;
+	}
+
+
+	/**
+	 * Extracts related models from Custom Selects and sets up any joins for those related models.
+	 *
+	 * @param EE_Model_Query_Info_Carrier $query_info_carrier
+	 * @throws EE_Error
+	 */
+	private function extractRelatedModelsFromCustomSelects(EE_Model_Query_Info_Carrier $query_info_carrier)
+	{
+		if (
+			$this->_custom_selections instanceof CustomSelects
+			&& (
+				$this->_custom_selections->type() === CustomSelects::TYPE_STRUCTURED
+				|| $this->_custom_selections->type() == CustomSelects::TYPE_COMPLEX
+			)
+		) {
+			$original_selects = $this->_custom_selections->originalSelects();
+			foreach ($original_selects as $alias => $select_configuration) {
+				$this->extractJoinModelFromQueryParams(
+					$query_info_carrier,
+					$select_configuration[0],
+					$select_configuration[0],
+					'custom_selects'
+				);
+			}
+		}
+	}
+
+
+	/**
+	 * Privately used by _extract_related_model_info_from_query_param to add a join to $model_name
+	 * and store it on $passed_in_query_info
+	 *
+	 * @param string                      $model_name
+	 * @param EE_Model_Query_Info_Carrier $passed_in_query_info
+	 * @param string                      $original_query_param used to extract the relation chain between the queried
+	 *                                                          model and $model_name. Eg, if we are querying Event,
+	 *                                                          and are adding a join to 'Payment' with the original
+	 *                                                          query param key
+	 *                                                          'Registration.Transaction.Payment.PAY_amount', we want
+	 *                                                          to extract 'Registration.Transaction.Payment', in case
+	 *                                                          Payment wants to add default query params so that it
+	 *                                                          will know what models to prepend onto its default query
+	 *                                                          params or in case it wants to rename tables (in case
+	 *                                                          there are multiple joins to the same table)
+	 * @return void
+	 * @throws EE_Error
+	 */
+	private function _add_join_to_model(
+		$model_name,
+		EE_Model_Query_Info_Carrier $passed_in_query_info,
+		$original_query_param
+	) {
+		$relation_obj         = $this->related_settings_for($model_name);
+		$model_relation_chain = EE_Model_Parser::extract_model_relation_chain($model_name, $original_query_param);
+		// check if the relation is HABTM, because then we're essentially doing two joins
+		// If so, join first to the JOIN table, and add its data types, and then continue as normal
+		if ($relation_obj instanceof EE_HABTM_Relation) {
+			$join_model_obj = $relation_obj->get_join_model();
+			// replace the model specified with the join model for this relation chain, whi
+			$relation_chain_to_join_model =
+				EE_Model_Parser::replace_model_name_with_join_model_name_in_model_relation_chain(
+					$model_name,
+					$join_model_obj->get_this_model_name(),
+					$model_relation_chain
+				);
+			$passed_in_query_info->merge(
+				new EE_Model_Query_Info_Carrier(
+					[$relation_chain_to_join_model => $join_model_obj->get_this_model_name()],
+					$relation_obj->get_join_to_intermediate_model_statement($relation_chain_to_join_model)
+				)
+			);
+		}
+		// now just join to the other table pointed to by the relation object, and add its data types
+		$passed_in_query_info->merge(
+			new EE_Model_Query_Info_Carrier(
+				[$model_relation_chain => $model_name],
+				$relation_obj->get_join_statement($model_relation_chain)
+			)
+		);
+	}
+
+
+	/**
+	 * Constructs SQL for where clause, like "WHERE Event.ID = 23 AND Transaction.amount > 100" etc.
+	 *
+	 * @param array $where_params @see
+	 *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @return string of SQL
+	 * @throws EE_Error
+	 */
+	private function _construct_where_clause($where_params)
+	{
+		$SQL = $this->_construct_condition_clause_recursive($where_params, ' AND ');
+		if ($SQL) {
+			return " WHERE " . $SQL;
+		}
+		return '';
+	}
+
+
+	/**
+	 * Just like the _construct_where_clause, except prepends 'HAVING' instead of 'WHERE',
+	 * and should be passed HAVING parameters, not WHERE parameters
+	 *
+	 * @param array $having_params
+	 * @return string
+	 * @throws EE_Error
+	 */
+	private function _construct_having_clause($having_params)
+	{
+		$SQL = $this->_construct_condition_clause_recursive($having_params, ' AND ');
+		if ($SQL) {
+			return " HAVING " . $SQL;
+		}
+		return '';
+	}
+
+
+	/**
+	 * Used for creating nested WHERE conditions. Eg "WHERE ! (Event.ID = 3 OR ( Event_Meta.meta_key = 'bob' AND
+	 * Event_Meta.meta_value = 'foo'))"
+	 *
+	 * @param array  $where_params @see
+	 *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @param string $glue         joins each subclause together. Should really only be " AND " or " OR "...
+	 * @return string of SQL
+	 * @throws EE_Error
+	 */
+	private function _construct_condition_clause_recursive($where_params, $glue = ' AND')
+	{
+		$where_clauses = [];
+		foreach ($where_params as $query_param => $op_and_value_or_sub_condition) {
+			$query_param = $this->_remove_stars_and_anything_after_from_condition_query_param_key($query_param);
+			if (in_array($query_param, $this->_logic_query_param_keys, true)) {
+				switch ($query_param) {
+					case 'not':
+					case 'NOT':
+						$where_clauses[] = "! ("
+										   . $this->_construct_condition_clause_recursive(
+											   $op_and_value_or_sub_condition,
+											   $glue
+										   )
+										   . ")";
+						break;
+					case 'and':
+					case 'AND':
+						$where_clauses[] = " ("
+										   . $this->_construct_condition_clause_recursive(
+											   $op_and_value_or_sub_condition,
+											   ' AND '
+										   )
+										   . ")";
+						break;
+					case 'or':
+					case 'OR':
+						$where_clauses[] = " ("
+										   . $this->_construct_condition_clause_recursive(
+											   $op_and_value_or_sub_condition,
+											   ' OR '
+										   )
+										   . ")";
+						break;
+				}
+			} else {
+				$field_obj = $this->_deduce_field_from_query_param($query_param);
+				// if it's not a normal field, maybe it's a custom selection?
+				if (! $field_obj) {
+					if ($this->_custom_selections instanceof CustomSelects) {
+						$field_obj = $this->_custom_selections->getDataTypeForAlias($query_param);
+					} else {
+						throw new EE_Error(
+							sprintf(
+								esc_html__(
+									"%s is neither a valid model field name, nor a custom selection",
+									"event_espresso"
+								),
+								$query_param
+							)
+						);
+					}
+				}
+				$op_and_value_sql = $this->_construct_op_and_value($op_and_value_or_sub_condition, $field_obj);
+				$where_clauses[]  = $this->_deduce_column_name_from_query_param($query_param) . SP . $op_and_value_sql;
+			}
+		}
+		return $where_clauses ? implode($glue, $where_clauses) : '';
+	}
+
+
+	/**
+	 * Takes the input parameter and extract the table name (alias) and column name
+	 *
+	 * @param string $query_param like Registration.Transaction.TXN_ID, Event.Datetime.start_time, or REG_ID
+	 * @return string table alias and column name for SQL, eg "Transaction.TXN_ID"
+	 * @throws EE_Error
+	 */
+	private function _deduce_column_name_from_query_param($query_param)
+	{
+		$field = $this->_deduce_field_from_query_param($query_param);
+		if ($field) {
+			$table_alias_prefix = EE_Model_Parser::extract_table_alias_model_relation_chain_from_query_param(
+				$field->get_model_name(),
+				$query_param
+			);
+			return $table_alias_prefix . $field->get_qualified_column();
+		}
+		if (
+			$this->_custom_selections instanceof CustomSelects
+			&& in_array($query_param, $this->_custom_selections->columnAliases(), true)
+		) {
+			// maybe it's custom selection item?
+			// if so, just use it as the "column name"
+			return $query_param;
+		}
+		$custom_select_aliases = $this->_custom_selections instanceof CustomSelects
+			? implode(',', $this->_custom_selections->columnAliases())
+			: '';
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					"%s is not a valid field on this model, nor a custom selection (%s)",
+					"event_espresso"
+				),
+				$query_param,
+				$custom_select_aliases
+			)
+		);
+	}
+
+
+	/**
+	 * Removes the * and anything after it from the condition query param key. It is useful to add the * to condition
+	 * query param keys (eg, 'OR*', 'EVT_ID') in order for the array keys to still be unique, so that they don't get
+	 * overwritten Takes a string like 'Event.EVT_ID*', 'TXN_total**', 'OR*1st', and 'DTT_reg_start*foobar' to
+	 * 'Event.EVT_ID', 'TXN_total', 'OR', and 'DTT_reg_start', respectively.
+	 *
+	 * @param string $condition_query_param_key
+	 * @return string
+	 */
+	private function _remove_stars_and_anything_after_from_condition_query_param_key($condition_query_param_key)
+	{
+		$pos_of_star = strpos($condition_query_param_key, '*');
+		if ($pos_of_star === false) {
+			return $condition_query_param_key;
+		}
+		$condition_query_param_sans_star = substr($condition_query_param_key, 0, $pos_of_star);
+		return $condition_query_param_sans_star;
+	}
+
+
+	/**
+	 * creates the SQL for the operator and the value in a WHERE clause, eg "< 23" or "LIKE '%monkey%'"
+	 *
+	 * @param mixed      array | string    $op_and_value
+	 * @param EE_Model_Field_Base|string $field_obj . If string, should be one of EEM_Base::_valid_wpdb_data_types
+	 * @return string
+	 * @throws EE_Error
+	 */
+	private function _construct_op_and_value($op_and_value, $field_obj)
+	{
+		if (is_array($op_and_value)) {
+			$operator = isset($op_and_value[0]) ? $this->_prepare_operator_for_sql($op_and_value[0]) : null;
+			if (! $operator) {
+				$php_array_like_string = [];
+				foreach ($op_and_value as $key => $value) {
+					$php_array_like_string[] = "$key=>$value";
+				}
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							"You setup a query parameter like you were going to specify an operator, but didn't. You provided '(%s)', but the operator should be at array key index 0 (eg array('>',32))",
+							"event_espresso"
+						),
+						implode(",", $php_array_like_string)
+					)
+				);
+			}
+			$value = isset($op_and_value[1]) ? $op_and_value[1] : null;
+		} else {
+			$operator = '=';
+			$value    = $op_and_value;
+		}
+		// check to see if the value is actually another field
+		if (is_array($op_and_value) && isset($op_and_value[2]) && $op_and_value[2] == true) {
+			return $operator . SP . $this->_deduce_column_name_from_query_param($value);
+		}
+		if (in_array($operator, $this->valid_in_style_operators()) && is_array($value)) {
+			// in this case, the value should be an array, or at least a comma-separated list
+			// it will need to handle a little differently
+			$cleaned_value = $this->_construct_in_value($value, $field_obj);
+			// note: $cleaned_value has already been run through $wpdb->prepare()
+			return $operator . SP . $cleaned_value;
+		}
+		if (in_array($operator, $this->valid_between_style_operators()) && is_array($value)) {
+			// the value should be an array with count of two.
+			if (count($value) !== 2) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							"The '%s' operator must be used with an array of values and there must be exactly TWO values in that array.",
+							'event_espresso'
+						),
+						"BETWEEN"
+					)
+				);
+			}
+			$cleaned_value = $this->_construct_between_value($value, $field_obj);
+			return $operator . SP . $cleaned_value;
+		}
+		if (in_array($operator, $this->valid_null_style_operators())) {
+			if ($value !== null) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							"You attempted to give a value  (%s) while using a NULL-style operator (%s). That isn't valid",
+							"event_espresso"
+						),
+						$value,
+						$operator
+					)
+				);
+			}
+			return $operator;
+		}
+		if (in_array($operator, $this->valid_like_style_operators()) && ! is_array($value)) {
+			// if the operator is 'LIKE', we want to allow percent signs (%) and not
+			// remove other junk. So just treat it as a string.
+			return $operator . SP . $this->_wpdb_prepare_using_field($value, '%s');
+		}
+		if (! in_array($operator, $this->valid_in_style_operators()) && ! is_array($value)) {
+			return $operator . SP . $this->_wpdb_prepare_using_field($value, $field_obj);
+		}
+		if (in_array($operator, $this->valid_in_style_operators()) && ! is_array($value)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"Operator '%s' must be used with an array of values, eg 'Registration.REG_ID' => array('%s',array(1,2,3))",
+						'event_espresso'
+					),
+					$operator,
+					$operator
+				)
+			);
+		}
+		if (! in_array($operator, $this->valid_in_style_operators()) && is_array($value)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"Operator '%s' must be used with a single value, not an array. Eg 'Registration.REG_ID => array('%s',23))",
+						'event_espresso'
+					),
+					$operator,
+					$operator
+				)
+			);
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					"It appears you've provided some totally invalid query parameters. Operator and value were:'%s', which isn't right at all",
+					"event_espresso"
+				),
+				http_build_query($op_and_value)
+			)
+		);
+	}
+
+
+	/**
+	 * Creates the operands to be used in a BETWEEN query, eg "'2014-12-31 20:23:33' AND '2015-01-23 12:32:54'"
+	 *
+	 * @param array                      $values
+	 * @param EE_Model_Field_Base|string $field_obj if string, it should be the datatype to be used when querying, eg
+	 *                                              '%s'
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function _construct_between_value($values, $field_obj)
+	{
+		$cleaned_values = [];
+		foreach ($values as $value) {
+			$cleaned_values[] = $this->_wpdb_prepare_using_field($value, $field_obj);
+		}
+		return $cleaned_values[0] . " AND " . $cleaned_values[1];
+	}
+
+
+	/**
+	 * Takes an array or a comma-separated list of $values and cleans them
+	 * according to $data_type using $wpdb->prepare, and then makes the list a
+	 * string surrounded by ( and ). Eg, _construct_in_value(array(1,2,3),'%d') would
+	 * return '(1,2,3)'; _construct_in_value("1,2,hack",'%d') would return '(1,2,1)' (assuming
+	 * I'm right that a string, when interpreted as a digit, becomes a 1. It might become a 0)
+	 *
+	 * @param mixed                      $values    array or comma-separated string
+	 * @param EE_Model_Field_Base|string $field_obj if string, it should be a wpdb data type like '%s', or '%d'
+	 * @return string of SQL to follow an 'IN' or 'NOT IN' operator
+	 * @throws EE_Error
+	 */
+	public function _construct_in_value($values, $field_obj)
+	{
+		$prepped = [];
+		// check if the value is a CSV list
+		if (is_string($values)) {
+			// in which case, turn it into an array
+			$values = explode(',', $values);
+		}
+		// make sure we only have one of each value in the list
+		$values = array_unique($values);
+		foreach ($values as $value) {
+			$prepped[] = $this->_wpdb_prepare_using_field($value, $field_obj);
+		}
+		// we would just LOVE to leave $cleaned_values as an empty array, and return the value as "()",
+		// but unfortunately that's invalid SQL. So instead we return a string which we KNOW will evaluate to be the empty set
+		// which is effectively equivalent to returning "()". We don't return "(0)" because that only works for auto-incrementing columns
+		if (empty($prepped)) {
+			$all_fields  = $this->field_settings();
+			$first_field = reset($all_fields);
+			$main_table  = $this->_get_main_table();
+			$prepped[]   = "SELECT {$first_field->get_table_column()} FROM {$main_table->get_table_name()} WHERE FALSE";
+		}
+		return '(' . implode(',', $prepped) . ')';
+	}
+
+
+	/**
+	 * @param mixed                      $value
+	 * @param EE_Model_Field_Base|string $field_obj if string it should be a wpdb data type like '%d'
+	 * @return false|null|string
+	 * @throws EE_Error
+	 */
+	private function _wpdb_prepare_using_field($value, $field_obj)
+	{
+		/** @type WPDB $wpdb */
+		global $wpdb;
+		if ($field_obj instanceof EE_Model_Field_Base) {
+			return $wpdb->prepare(
+				$field_obj->get_wpdb_data_type(),
+				$this->_prepare_value_for_use_in_db($value, $field_obj)
+			);
+		} //$field_obj should really just be a data type
+		if (! in_array($field_obj, $this->_valid_wpdb_data_types)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__("%s is not a valid wpdb datatype. Valid ones are %s", "event_espresso"),
+					$field_obj,
+					implode(",", $this->_valid_wpdb_data_types)
+				)
+			);
+		}
+		return $wpdb->prepare($field_obj, $value);
+	}
+
+
+	/**
+	 * Takes the input parameter and finds the model field that it indicates.
+	 *
+	 * @param string $query_param_name like Registration.Transaction.TXN_ID, Event.Datetime.start_time, or REG_ID
+	 * @return EE_Model_Field_Base
+	 * @throws EE_Error
+	 */
+	protected function _deduce_field_from_query_param($query_param_name)
+	{
+		// ok, now proceed with deducing which part is the model's name, and which is the field's name
+		// which will help us find the database table and column
+		$query_param_parts = explode(".", $query_param_name);
+		if (empty($query_param_parts)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"_extract_column_name is empty when trying to extract column and table name from %s",
+						'event_espresso'
+					),
+					$query_param_name
+				)
+			);
+		}
+		$number_of_parts       = count($query_param_parts);
+		$last_query_param_part = $query_param_parts[ count($query_param_parts) - 1 ];
+		if ($number_of_parts === 1) {
+			$field_name = $last_query_param_part;
+			$model_obj  = $this;
+		} else {// $number_of_parts >= 2
+			// the last part is the column name, and there are only 2parts. therefore...
+			$field_name = $last_query_param_part;
+			$model_obj  = $this->get_related_model_obj($query_param_parts[ $number_of_parts - 2 ]);
+		}
+		try {
+			return $model_obj->field_settings_for($field_name);
+		} catch (EE_Error $e) {
+			return null;
+		}
+	}
+
+
+	/**
+	 * Given a field's name (ie, a key in $this->field_settings()), uses the EE_Model_Field object to get the table's
+	 * alias and column which corresponds to it
+	 *
+	 * @param string $field_name
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function _get_qualified_column_for_field($field_name)
+	{
+		$all_fields = $this->field_settings();
+		$field      = isset($all_fields[ $field_name ]) ? $all_fields[ $field_name ] : false;
+		if ($field) {
+			return $field->get_qualified_column();
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					"There is no field titled %s on model %s. Either the query trying to use it is bad, or you need to add it to the list of fields on the model.",
+					'event_espresso'
+				),
+				$field_name,
+				get_class($this)
+			)
+		);
+	}
+
+
+	/**
+	 * similar to \EEM_Base::_get_qualified_column_for_field() but returns an array with data for ALL fields.
+	 * Example usage:
+	 * EEM_Ticket::instance()->get_all_wpdb_results(
+	 *      array(),
+	 *      ARRAY_A,
+	 *      EEM_Ticket::instance()->get_qualified_columns_for_all_fields()
+	 *  );
+	 * is equivalent to
+	 *  EEM_Ticket::instance()->get_all_wpdb_results( array(), ARRAY_A, '*' );
+	 * and
+	 *  EEM_Event::instance()->get_all_wpdb_results(
+	 *      array(
+	 *          array(
+	 *              'Datetime.Ticket.TKT_ID' => array( '<', 100 ),
+	 *          ),
+	 *          ARRAY_A,
+	 *          implode(
+	 *              ', ',
+	 *              array_merge(
+	 *                  EEM_Event::instance()->get_qualified_columns_for_all_fields( '', false ),
+	 *                  EEM_Ticket::instance()->get_qualified_columns_for_all_fields( 'Datetime', false )
+	 *              )
+	 *          )
+	 *      )
+	 *  );
+	 * selects rows from the database, selecting all the event and ticket columns, where the ticket ID is below 100
+	 *
+	 * @param string $model_relation_chain        the chain of models used to join between the model you want to query
+	 *                                            and the one whose fields you are selecting for example: when querying
+	 *                                            tickets model and selecting fields from the tickets model you would
+	 *                                            leave this parameter empty, because no models are needed to join
+	 *                                            between the queried model and the selected one. Likewise when
+	 *                                            querying the datetime model and selecting fields from the tickets
+	 *                                            model, it would also be left empty, because there is a direct
+	 *                                            relation from datetimes to tickets, so no model is needed to join
+	 *                                            them together. However, when querying from the event model and
+	 *                                            selecting fields from the ticket model, you should provide the string
+	 *                                            'Datetime', indicating that the event model must first join to the
+	 *                                            datetime model in order to find its relation to ticket model.
+	 *                                            Also, when querying from the venue model and selecting fields from
+	 *                                            the ticket model, you should provide the string 'Event.Datetime',
+	 *                                            indicating you need to join the venue model to the event model,
+	 *                                            to the datetime model, in order to find its relation to the ticket
+	 *                                            model. This string is used to deduce the prefix that gets added onto
+	 *                                            the models' tables qualified columns
+	 * @param bool   $return_string               if true, will return a string with qualified column names separated
+	 *                                            by ', ' if false, will simply return a numerically indexed array of
+	 *                                            qualified column names
+	 * @return array|string
+	 */
+	public function get_qualified_columns_for_all_fields($model_relation_chain = '', $return_string = true)
+	{
+		$table_prefix      = str_replace('.', '__', $model_relation_chain) . (empty($model_relation_chain) ? '' : '__');
+		$qualified_columns = [];
+		foreach ($this->field_settings() as $field_name => $field) {
+			$qualified_columns[] = $table_prefix . $field->get_qualified_column();
+		}
+		return $return_string ? implode(', ', $qualified_columns) : $qualified_columns;
+	}
+
+
+	/**
+	 * constructs the select use on special limit joins
+	 * NOTE: for now this has only been tested and will work when the  table alias is for the PRIMARY table. Although
+	 * its setup so the select query will be setup on and just doing the special select join off of the primary table
+	 * (as that is typically where the limits would be set).
+	 *
+	 * @param string       $table_alias The table the select is being built for
+	 * @param mixed|string $limit       The limit for this select
+	 * @return string                The final select join element for the query.
+	 * @throws EE_Error
+	 * @throws EE_Error
+	 */
+	public function _construct_limit_join_select($table_alias, $limit)
+	{
+		$SQL = '';
+		foreach ($this->_tables as $table_obj) {
+			if ($table_obj instanceof EE_Primary_Table) {
+				$SQL .= $table_alias === $table_obj->get_table_alias()
+					? $table_obj->get_select_join_limit($limit)
+					: SP . $table_obj->get_table_name() . " AS " . $table_obj->get_table_alias() . SP;
+			} elseif ($table_obj instanceof EE_Secondary_Table) {
+				$SQL .= $table_alias === $table_obj->get_table_alias()
+					? $table_obj->get_select_join_limit_join($limit)
+					: SP . $table_obj->get_join_sql($table_alias) . SP;
+			}
+		}
+		return $SQL;
+	}
+
+
+	/**
+	 * Constructs the internal join if there are multiple tables, or simply the table's name and alias
+	 * Eg "wp_post AS Event" or "wp_post AS Event INNER JOIN wp_postmeta Event_Meta ON Event.ID = Event_Meta.post_id"
+	 *
+	 * @return string SQL
+	 * @throws EE_Error
+	 */
+	public function _construct_internal_join()
+	{
+		$SQL = $this->_get_main_table()->get_table_sql();
+		$SQL .= $this->_construct_internal_join_to_table_with_alias($this->_get_main_table()->get_table_alias());
+		return $SQL;
+	}
+
+
+	/**
+	 * Constructs the SQL for joining all the tables on this model.
+	 * Normally $alias should be the primary table's alias, but in cases where
+	 * we have already joined to a secondary table (eg, the secondary table has a foreign key and is joined before the
+	 * primary table) then we should provide that secondary table's alias. Eg, with $alias being the primary table's
+	 * alias, this will construct SQL like:
+	 * " INNER JOIN wp_esp_secondary_table AS Secondary_Table ON Primary_Table.pk = Secondary_Table.fk".
+	 * With $alias being a secondary table's alias, this will construct SQL like:
+	 * " INNER JOIN wp_esp_primary_table AS Primary_Table ON Primary_Table.pk = Secondary_Table.fk".
+	 *
+	 * @param string $alias_prefixed table alias to join to (this table should already be in the FROM SQL clause)
+	 * @return string
+	 * @throws EE_Error
+	 * @throws EE_Error
+	 */
+	public function _construct_internal_join_to_table_with_alias($alias_prefixed)
+	{
+		$SQL               = '';
+		$alias_sans_prefix = EE_Model_Parser::remove_table_alias_model_relation_chain_prefix($alias_prefixed);
+		foreach ($this->_tables as $table_obj) {
+			if ($table_obj instanceof EE_Secondary_Table) {// table is secondary table
+				if ($alias_sans_prefix === $table_obj->get_table_alias()) {
+					// so we're joining to this table, meaning the table is already in
+					// the FROM statement, BUT the primary table isn't. So we want
+					// to add the inverse join sql
+					$SQL .= $table_obj->get_inverse_join_sql($alias_prefixed);
+				} else {
+					// just add a regular JOIN to this table from the primary table
+					$SQL .= $table_obj->get_join_sql($alias_prefixed);
+				}
+			}//if it's a primary table, dont add any SQL. it should already be in the FROM statement
+		}
+		return $SQL;
+	}
+
+
+	/**
+	 * Gets an array for storing all the data types on the next-to-be-executed-query.
+	 * This should be a growing array of keys being table-columns (eg 'EVT_ID' and 'Event.EVT_ID'), and values being
+	 * their data type (eg, '%s', '%d', etc)
+	 *
+	 * @return array
+	 */
+	public function _get_data_types()
+	{
+		$data_types = [];
+		foreach ($this->field_settings() as $field_obj) {
+			// $data_types[$field_obj->get_table_column()] = $field_obj->get_wpdb_data_type();
+			/** @var $field_obj EE_Model_Field_Base */
+			$data_types[ $field_obj->get_qualified_column() ] = $field_obj->get_wpdb_data_type();
+		}
+		return $data_types;
+	}
+
+
+	/**
+	 * Gets the model object given the relation's name / model's name (eg, 'Event', 'Registration',etc. Always singular)
+	 *
+	 * @param string $model_name
+	 * @return EEM_Base
+	 * @throws EE_Error
+	 */
+	public function get_related_model_obj($model_name)
+	{
+		$model_classname = "EEM_" . $model_name;
+		if (! class_exists($model_classname)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"You specified a related model named %s in your query. No such model exists, if it did, it would have the classname %s",
+						'event_espresso'
+					),
+					$model_name,
+					$model_classname
+				)
+			);
+		}
+		return call_user_func($model_classname . "::instance");
+	}
+
+
+	/**
+	 * Returns the array of EE_ModelRelations for this model.
+	 *
+	 * @return EE_Model_Relation_Base[]
+	 */
+	public function relation_settings()
+	{
+		return $this->_model_relations;
+	}
+
+
+	/**
+	 * Gets all related models that this model BELONGS TO. Handy to know sometimes
+	 * because without THOSE models, this model probably doesn't have much purpose.
+	 * (Eg, without an event, datetimes have little purpose.)
+	 *
+	 * @return EE_Belongs_To_Relation[]
+	 */
+	public function belongs_to_relations()
+	{
+		$belongs_to_relations = [];
+		foreach ($this->relation_settings() as $model_name => $relation_obj) {
+			if ($relation_obj instanceof EE_Belongs_To_Relation) {
+				$belongs_to_relations[ $model_name ] = $relation_obj;
+			}
+		}
+		return $belongs_to_relations;
+	}
+
+
+	/**
+	 * Returns the specified EE_Model_Relation, or throws an exception
+	 *
+	 * @param string $relation_name name of relation, key in $this->_relatedModels
+	 * @return EE_Model_Relation_Base
+	 * @throws EE_Error
+	 */
+	public function related_settings_for($relation_name)
+	{
+		$relatedModels = $this->relation_settings();
+		if (! array_key_exists($relation_name, $relatedModels)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'Cannot get %s related to %s. There is no model relation of that type. There is, however, %s...',
+						'event_espresso'
+					),
+					$relation_name,
+					$this->_get_class_name(),
+					implode(', ', array_keys($relatedModels))
+				)
+			);
+		}
+		return $relatedModels[ $relation_name ];
+	}
+
+
+	/**
+	 * A convenience method for getting a specific field's settings, instead of getting all field settings for all
+	 * fields
+	 *
+	 * @param string  $fieldName
+	 * @param boolean $include_db_only_fields
+	 * @return EE_Model_Field_Base
+	 * @throws EE_Error
+	 */
+	public function field_settings_for($fieldName, $include_db_only_fields = true)
+	{
+		$fieldSettings = $this->field_settings($include_db_only_fields);
+		if (! array_key_exists($fieldName, $fieldSettings)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__("There is no field/column '%s' on '%s'", 'event_espresso'),
+					$fieldName,
+					get_class($this)
+				)
+			);
+		}
+		return $fieldSettings[ $fieldName ];
+	}
+
+
+	/**
+	 * Checks if this field exists on this model
+	 *
+	 * @param string $fieldName a key in the model's _field_settings array
+	 * @return boolean
+	 */
+	public function has_field($fieldName)
+	{
+		$fieldSettings = $this->field_settings(true);
+		if (isset($fieldSettings[ $fieldName ])) {
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * Returns whether or not this model has a relation to the specified model
+	 *
+	 * @param string $relation_name possibly one of the keys in the relation_settings array
+	 * @return boolean
+	 */
+	public function has_relation($relation_name)
+	{
+		$relations = $this->relation_settings();
+		if (isset($relations[ $relation_name ])) {
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * gets the field object of type 'primary_key' from the fieldsSettings attribute.
+	 * Eg, on EE_Answer that would be ANS_ID field object
+	 *
+	 * @param $field_obj
+	 * @return boolean
+	 */
+	public function is_primary_key_field($field_obj)
+	{
+		return $field_obj instanceof EE_Primary_Key_Field_Base ? true : false;
+	}
+
+
+	/**
+	 * gets the field object of type 'primary_key' from the fieldsSettings attribute.
+	 * Eg, on EE_Answer that would be ANS_ID field object
+	 *
+	 * @return EE_Primary_Key_Field_Base
+	 * @throws EE_Error
+	 */
+	public function get_primary_key_field()
+	{
+		if ($this->_primary_key_field === null) {
+			foreach ($this->field_settings(true) as $field_obj) {
+				if ($this->is_primary_key_field($field_obj)) {
+					$this->_primary_key_field = $field_obj;
+					break;
+				}
+			}
+			if (! $this->_primary_key_field instanceof EE_Primary_Key_Field_Base) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__("There is no Primary Key defined on model %s", 'event_espresso'),
+						get_class($this)
+					)
+				);
+			}
+		}
+		return $this->_primary_key_field;
+	}
+
+
+	/**
+	 * Returns whether or not not there is a primary key on this model.
+	 * Internally does some caching.
+	 *
+	 * @return boolean
+	 */
+	public function has_primary_key_field()
+	{
+		if ($this->_has_primary_key_field === null) {
+			try {
+				$this->get_primary_key_field();
+				$this->_has_primary_key_field = true;
+			} catch (EE_Error $e) {
+				$this->_has_primary_key_field = false;
+			}
+		}
+		return $this->_has_primary_key_field;
+	}
+
+
+	/**
+	 * Finds the first field of type $field_class_name.
+	 *
+	 * @param string $field_class_name class name of field that you want to find. Eg, EE_Datetime_Field,
+	 *                                 EE_Foreign_Key_Field, etc
+	 * @return EE_Model_Field_Base or null if none is found
+	 */
+	public function get_a_field_of_type($field_class_name)
+	{
+		foreach ($this->field_settings() as $field) {
+			if ($field instanceof $field_class_name) {
+				return $field;
+			}
+		}
+		return null;
+	}
+
+
+	/**
+	 * Gets a foreign key field pointing to model.
+	 *
+	 * @param string $model_name eg Event, Registration, not EEM_Event
+	 * @return EE_Foreign_Key_Field_Base
+	 * @throws EE_Error
+	 */
+	public function get_foreign_key_to($model_name)
+	{
+		if (! isset($this->_cache_foreign_key_to_fields[ $model_name ])) {
+			foreach ($this->field_settings() as $field) {
+				if (
+					$field instanceof EE_Foreign_Key_Field_Base
+					&& in_array($model_name, $field->get_model_names_pointed_to())
+				) {
+					$this->_cache_foreign_key_to_fields[ $model_name ] = $field;
+					break;
+				}
+			}
+			if (! isset($this->_cache_foreign_key_to_fields[ $model_name ])) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							"There is no foreign key field pointing to model %s on model %s",
+							'event_espresso'
+						),
+						$model_name,
+						get_class($this)
+					)
+				);
+			}
+		}
+		return $this->_cache_foreign_key_to_fields[ $model_name ];
+	}
+
+
+	/**
+	 * Gets the table name (including $wpdb->prefix) for the table alias
+	 *
+	 * @param string $table_alias eg Event, Event_Meta, Registration, Transaction, but maybe
+	 *                            a table alias with a model chain prefix, like 'Venue__Event_Venue___Event_Meta'.
+	 *                            Either one works
+	 * @return string
+	 */
+	public function get_table_for_alias($table_alias)
+	{
+		$table_alias_sans_model_relation_chain_prefix =
+			EE_Model_Parser::remove_table_alias_model_relation_chain_prefix($table_alias);
+		return $this->_tables[ $table_alias_sans_model_relation_chain_prefix ]->get_table_name();
+	}
+
+
+	/**
+	 * Returns a flat array of all field son this model, instead of organizing them
+	 * by table_alias as they are in the constructor.
+	 *
+	 * @param bool $include_db_only_fields flag indicating whether or not to include the db-only fields
+	 * @return EE_Model_Field_Base[] where the keys are the field's name
+	 */
+	public function field_settings($include_db_only_fields = false)
+	{
+		if ($include_db_only_fields) {
+			if ($this->_cached_fields === null) {
+				$this->_cached_fields = [];
+				foreach ($this->_fields as $fields_corresponding_to_table) {
+					foreach ($fields_corresponding_to_table as $field_name => $field_obj) {
+						$this->_cached_fields[ $field_name ] = $field_obj;
+					}
+				}
+			}
+			return $this->_cached_fields;
+		}
+		if ($this->_cached_fields_non_db_only === null) {
+			$this->_cached_fields_non_db_only = [];
+			foreach ($this->_fields as $fields_corresponding_to_table) {
+				foreach ($fields_corresponding_to_table as $field_name => $field_obj) {
+					/** @var $field_obj EE_Model_Field_Base */
+					if (! $field_obj->is_db_only_field()) {
+						$this->_cached_fields_non_db_only[ $field_name ] = $field_obj;
+					}
+				}
+			}
+		}
+		return $this->_cached_fields_non_db_only;
+	}
+
+
+	/**
+	 *        cycle though array of attendees and create objects out of each item
+	 *
+	 * @access        private
+	 * @param array $rows        of results of $wpdb->get_results($query,ARRAY_A)
+	 * @return EE_Base_Class[] array keys are primary keys (if there is a primary key on the model. if not,
+	 *                           numerically indexed)
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _create_objects($rows = [])
+	{
+		$array_of_objects = [];
+		if (empty($rows)) {
+			return [];
+		}
+		$count_if_model_has_no_primary_key = 0;
+		$has_primary_key                   = $this->has_primary_key_field();
+		$primary_key_field                 = $has_primary_key ? $this->get_primary_key_field() : null;
+		foreach ((array) $rows as $row) {
+			if (empty($row)) {
+				// wp did its weird thing where it returns an array like array(0=>null), which is totally not helpful...
+				return [];
+			}
+			// check if we've already set this object in the results array,
+			// in which case there's no need to process it further (again)
+			if ($has_primary_key) {
+				$table_pk_value = $this->_get_column_value_with_table_alias_or_not(
+					$row,
+					$primary_key_field->get_qualified_column(),
+					$primary_key_field->get_table_column()
+				);
+				if ($table_pk_value && isset($array_of_objects[ $table_pk_value ])) {
+					continue;
+				}
+			}
+			$classInstance = $this->instantiate_class_from_array_or_object($row);
+			if (! $classInstance) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__('Could not create instance of class %s from row %s', 'event_espresso'),
+						$this->get_this_model_name(),
+						http_build_query($row)
+					)
+				);
+			}
+			// set the timezone on the instantiated objects
+			$classInstance->set_timezone($this->_timezone);
+			// make sure if there is any timezone setting present that we set the timezone for the object
+			$key                      = $has_primary_key ? $classInstance->ID() : $count_if_model_has_no_primary_key++;
+			$array_of_objects[ $key ] = $classInstance;
+			// also, for all the relations of type BelongsTo, see if we can cache
+			// those related models
+			// (we could do this for other relations too, but if there are conditions
+			// that filtered out some fo the results, then we'd be caching an incomplete set
+			// so it requires a little more thought than just caching them immediately...)
+			foreach ($this->_model_relations as $modelName => $relation_obj) {
+				if ($relation_obj instanceof EE_Belongs_To_Relation) {
+					// check if this model's INFO is present. If so, cache it on the model
+					$other_model           = $relation_obj->get_other_model();
+					$other_model_obj_maybe = $other_model->instantiate_class_from_array_or_object($row);
+					// if we managed to make a model object from the results, cache it on the main model object
+					if ($other_model_obj_maybe) {
+						// set timezone on these other model objects if they are present
+						$other_model_obj_maybe->set_timezone($this->_timezone);
+						$classInstance->cache($modelName, $other_model_obj_maybe);
+					}
+				}
+			}
+			// also, if this was a custom select query, let's see if there are any results for the custom select fields
+			// and add them to the object as well.  We'll convert according to the set data_type if there's any set for
+			// the field in the CustomSelects object
+			if ($this->_custom_selections instanceof CustomSelects) {
+				$classInstance->setCustomSelectsValues(
+					$this->getValuesForCustomSelectAliasesFromResults($row)
+				);
+			}
+		}
+		return $array_of_objects;
+	}
+
+
+	/**
+	 * This will parse a given row of results from the db and see if any keys in the results match an alias within the
+	 * current CustomSelects object. This will be used to build an array of values indexed by those keys.
+	 *
+	 * @param array $db_results_row
+	 * @return array
+	 */
+	protected function getValuesForCustomSelectAliasesFromResults(array $db_results_row)
+	{
+		$results = [];
+		if ($this->_custom_selections instanceof CustomSelects) {
+			foreach ($this->_custom_selections->columnAliases() as $alias) {
+				if (isset($db_results_row[ $alias ])) {
+					$results[ $alias ] = $this->convertValueToDataType(
+						$db_results_row[ $alias ],
+						$this->_custom_selections->getDataTypeForAlias($alias)
+					);
+				}
+			}
+		}
+		return $results;
+	}
+
+
+	/**
+	 * This will set the value for the given alias
+	 *
+	 * @param string $value
+	 * @param string $datatype (one of %d, %s, %f)
+	 * @return int|string|float (int for %d, string for %s, float for %f)
+	 */
+	protected function convertValueToDataType($value, $datatype)
+	{
+		switch ($datatype) {
+			case '%f':
+				return (float) $value;
+			case '%d':
+				return (int) $value;
+			default:
+				return (string) $value;
+		}
+	}
+
+
+	/**
+	 * The purpose of this method is to allow us to create a model object that is not in the db that holds default
+	 * values. A typical example of where this is used is when creating a new item and the initial load of a form.  We
+	 * dont' necessarily want to test for if the object is present but just assume it is BUT load the defaults from the
+	 * object (as set in the model_field!).
+	 *
+	 * @return EE_Base_Class single EE_Base_Class object with default values for the properties.
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function create_default_object()
+	{
+		$this_model_fields_and_values = [];
+		// setup the row using default values;
+		foreach ($this->field_settings() as $field_name => $field_obj) {
+			$this_model_fields_and_values[ $field_name ] = $field_obj->get_default_value();
+		}
+		$className     = $this->_get_class_name();
+		return EE_Registry::instance()->load_class($className, [$this_model_fields_and_values], false, false);
+	}
+
+
+	/**
+	 * @param mixed $cols_n_values either an array of where each key is the name of a field, and the value is its value
+	 *                             or an stdClass where each property is the name of a column,
+	 * @return EE_Base_Class
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function instantiate_class_from_array_or_object($cols_n_values)
+	{
+		if (! is_array($cols_n_values) && is_object($cols_n_values)) {
+			$cols_n_values = get_object_vars($cols_n_values);
+		}
+		$primary_key = null;
+		// make sure the array only has keys that are fields/columns on this model
+		$this_model_fields_n_values = $this->_deduce_fields_n_values_from_cols_n_values($cols_n_values);
+		if ($this->has_primary_key_field() && isset($this_model_fields_n_values[ $this->primary_key_name() ])) {
+			$primary_key = $this_model_fields_n_values[ $this->primary_key_name() ];
+		}
+		$className = $this->_get_class_name();
+		// check we actually found results that we can use to build our model object
+		// if not, return null
+		if ($this->has_primary_key_field()) {
+			if (empty($this_model_fields_n_values[ $this->primary_key_name() ])) {
+				return null;
+			}
+		} elseif ($this->unique_indexes()) {
+			$first_column = reset($this_model_fields_n_values);
+			if (empty($first_column)) {
+				return null;
+			}
+		}
+		// if there is no primary key or the object doesn't already exist in the entity map, then create a new instance
+		if ($primary_key) {
+			$classInstance = $this->get_from_entity_map($primary_key);
+			if (! $classInstance) {
+				$classInstance = EE_Registry::instance()
+											->load_class(
+												$className,
+												[$this_model_fields_n_values, $this->_timezone],
+												true,
+												false
+											);
+				// add this new object to the entity map
+				$classInstance = $this->add_to_entity_map($classInstance);
+			}
+		} else {
+			$classInstance = EE_Registry::instance()
+										->load_class(
+											$className,
+											[$this_model_fields_n_values, $this->_timezone],
+											true,
+											false
+										);
+		}
+		return $classInstance;
+	}
+
+
+	/**
+	 * Gets the model object from the  entity map if it exists
+	 *
+	 * @param int|string $id the ID of the model object
+	 * @return EE_Base_Class
+	 */
+	public function get_from_entity_map($id)
+	{
+		return isset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ])
+			? $this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ] : null;
+	}
+
+
+	/**
+	 * add_to_entity_map
+	 * Adds the object to the model's entity mappings
+	 *        Effectively tells the models "Hey, this model object is the most up-to-date representation of the data,
+	 *        and for the remainder of the request, it's even more up-to-date than what's in the database.
+	 *        So, if the database doesn't agree with what's in the entity mapper, ignore the database"
+	 *        If the database gets updated directly and you want the entity mapper to reflect that change,
+	 *        then this method should be called immediately after the update query
+	 * Note: The map is indexed by whatever the current blog id is set (via EEM_Base::$_model_query_blog_id).  This is
+	 * so on multisite, the entity map is specific to the query being done for a specific site.
+	 *
+	 * @param EE_Base_Class $object
+	 * @return EE_Base_Class
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function add_to_entity_map(EE_Base_Class $object)
+	{
+		$className = $this->_get_class_name();
+		if (! $object instanceof $className) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__("You tried adding a %s to a mapping of %ss", "event_espresso"),
+					is_object($object) ? get_class($object) : $object,
+					$className
+				)
+			);
+		}
+		/** @var $object EE_Base_Class */
+		if (! $object->ID()) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"You tried storing a model object with NO ID in the %s entity mapper.",
+						"event_espresso"
+					),
+					get_class($this)
+				)
+			);
+		}
+		// double check it's not already there
+		$classInstance = $this->get_from_entity_map($object->ID());
+		if ($classInstance) {
+			return $classInstance;
+		}
+		$this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $object->ID() ] = $object;
+		return $object;
+	}
+
+
+	/**
+	 * if a valid identifier is provided, then that entity is unset from the entity map,
+	 * if no identifier is provided, then the entire entity map is emptied
+	 *
+	 * @param int|string $id the ID of the model object
+	 * @return boolean
+	 */
+	public function clear_entity_map($id = null)
+	{
+		if (empty($id)) {
+			$this->_entity_map[ EEM_Base::$_model_query_blog_id ] = [];
+			return true;
+		}
+		if (isset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ])) {
+			unset($this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ]);
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * Public wrapper for _deduce_fields_n_values_from_cols_n_values.
+	 * Given an array where keys are column (or column alias) names and values,
+	 * returns an array of their corresponding field names and database values
+	 *
+	 * @param array $cols_n_values
+	 * @return array
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function deduce_fields_n_values_from_cols_n_values(array $cols_n_values): array
+	{
+		return $this->_deduce_fields_n_values_from_cols_n_values($cols_n_values);
+	}
+
+
+	/**
+	 * _deduce_fields_n_values_from_cols_n_values
+	 * Given an array where keys are column (or column alias) names and values,
+	 * returns an array of their corresponding field names and database values
+	 *
+	 * @param array|stdClass $cols_n_values
+	 * @return array
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _deduce_fields_n_values_from_cols_n_values($cols_n_values): array
+	{
+		if ($cols_n_values instanceof stdClass) {
+			$cols_n_values = get_object_vars($cols_n_values);
+		}
+		$this_model_fields_n_values = [];
+		foreach ($this->get_tables() as $table_alias => $table_obj) {
+			$table_pk_value = $this->_get_column_value_with_table_alias_or_not(
+				$cols_n_values,
+				$table_obj->get_fully_qualified_pk_column(),
+				$table_obj->get_pk_column()
+			);
+			// there is a primary key on this table and its not set. Use defaults for all its columns
+			if ($table_pk_value === null && $table_obj->get_pk_column()) {
+				foreach ($this->_get_fields_for_table($table_alias) as $field_name => $field_obj) {
+					if (! $field_obj->is_db_only_field()) {
+						// prepare field as if its coming from db
+						$prepared_value                            =
+							$field_obj->prepare_for_set($field_obj->get_default_value());
+						$this_model_fields_n_values[ $field_name ] = $field_obj->prepare_for_use_in_db($prepared_value);
+					}
+				}
+			} else {
+				// the table's rows existed. Use their values
+				foreach ($this->_get_fields_for_table($table_alias) as $field_name => $field_obj) {
+					if (! $field_obj->is_db_only_field()) {
+						$this_model_fields_n_values[ $field_name ] = $this->_get_column_value_with_table_alias_or_not(
+							$cols_n_values,
+							$field_obj->get_qualified_column(),
+							$field_obj->get_table_column()
+						);
+					}
+				}
+			}
+		}
+		return $this_model_fields_n_values;
+	}
+
+
+	/**
+	 * @param $cols_n_values
+	 * @param $qualified_column
+	 * @param $regular_column
+	 * @return null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _get_column_value_with_table_alias_or_not($cols_n_values, $qualified_column, $regular_column)
+	{
+		$value = null;
+		// ask the field what it think it's table_name.column_name should be, and call it the "qualified column"
+		// does the field on the model relate to this column retrieved from the db?
+		// or is it a db-only field? (not relating to the model)
+		if (isset($cols_n_values[ $qualified_column ])) {
+			$value = $cols_n_values[ $qualified_column ];
+		} elseif (isset($cols_n_values[ $regular_column ])) {
+			$value = $cols_n_values[ $regular_column ];
+		} elseif (! empty($this->foreign_key_aliases)) {
+			// no PK?  ok check if there is a foreign key alias set for this table
+			// then check if that alias exists in the incoming data
+			// AND that the actual PK the $FK_alias represents matches the $qualified_column (full PK)
+			foreach ($this->foreign_key_aliases as $FK_alias => $PK_column) {
+				if ($PK_column === $qualified_column && isset($cols_n_values[ $FK_alias ])) {
+					$value = $cols_n_values[ $FK_alias ];
+					[$pk_class] = explode('.', $PK_column);
+					$pk_model_name = "EEM_{$pk_class}";
+					/** @var EEM_Base $pk_model */
+					$pk_model = EE_Registry::instance()->load_model($pk_model_name);
+					if ($pk_model instanceof EEM_Base) {
+						// make sure object is pulled from db and added to entity map
+						$pk_model->get_one_by_ID($value);
+					}
+					break;
+				}
+			}
+		}
+		return $value;
+	}
+
+
+	/**
+	 * refresh_entity_map_from_db
+	 * Makes sure the model object in the entity map at $id assumes the values
+	 * of the database (opposite of EE_base_Class::save())
+	 *
+	 * @param int|string $id
+	 * @return EE_Base_Class|EE_Soft_Delete_Base_Class|mixed|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function refresh_entity_map_from_db($id)
+	{
+		$obj_in_map = $this->get_from_entity_map($id);
+		if ($obj_in_map) {
+			$wpdb_results = $this->_get_all_wpdb_results(
+				[[$this->get_primary_key_field()->get_name() => $id], 'limit' => 1]
+			);
+			if ($wpdb_results && is_array($wpdb_results)) {
+				$one_row = reset($wpdb_results);
+				foreach ($this->_deduce_fields_n_values_from_cols_n_values($one_row) as $field_name => $db_value) {
+					$obj_in_map->set_from_db($field_name, $db_value);
+				}
+				// clear the cache of related model objects
+				foreach ($this->relation_settings() as $relation_name => $relation_obj) {
+					$obj_in_map->clear_cache($relation_name, null, true);
+				}
+			}
+			$this->_entity_map[ EEM_Base::$_model_query_blog_id ][ $id ] = $obj_in_map;
+			return $obj_in_map;
+		}
+		return $this->get_one_by_ID($id);
+	}
+
+
+	/**
+	 * refresh_entity_map_with
+	 * Leaves the entry in the entity map alone, but updates it to match the provided
+	 * $replacing_model_obj (which we assume to be its equivalent but somehow NOT in the entity map).
+	 * This is useful if you have a model object you want to make authoritative over what's in the entity map currently.
+	 * Note: The old $replacing_model_obj should now be destroyed as it's now un-authoritative
+	 *
+	 * @param int|string    $id
+	 * @param EE_Base_Class $replacing_model_obj
+	 * @return EE_Base_Class
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function refresh_entity_map_with($id, $replacing_model_obj)
+	{
+		$obj_in_map = $this->get_from_entity_map($id);
+		if ($obj_in_map) {
+			if ($replacing_model_obj instanceof EE_Base_Class) {
+				foreach ($replacing_model_obj->model_field_array() as $field_name => $value) {
+					$obj_in_map->set($field_name, $value);
+				}
+				// make the model object in the entity map's cache match the $replacing_model_obj
+				foreach ($this->relation_settings() as $relation_name => $relation_obj) {
+					$obj_in_map->clear_cache($relation_name, null, true);
+					foreach ($replacing_model_obj->get_all_from_cache($relation_name) as $cache_id => $cached_obj) {
+						$obj_in_map->cache($relation_name, $cached_obj, $cache_id);
+					}
+				}
+			}
+			return $obj_in_map;
+		}
+		$this->add_to_entity_map($replacing_model_obj);
+		return $replacing_model_obj;
+	}
+
+
+	/**
+	 * Gets the EE class that corresponds to this model. Eg, for EEM_Answer that
+	 * would be EE_Answer.To import that class, you'd just add ".class.php" to the name, like so
+	 * require_once($this->_getClassName().".class.php");
+	 *
+	 * @return string
+	 */
+	private function _get_class_name()
+	{
+		return "EE_" . $this->get_this_model_name();
+	}
+
+
+	/**
+	 * Get the name of the items this model represents, for the quantity specified. Eg,
+	 * if $quantity==1, on EEM_Event, it would 'Event' (internationalized), otherwise
+	 * it would be 'Events'.
+	 *
+	 * @param int|float|null $quantity
+	 * @return string
+	 */
+	public function item_name($quantity = 1): string
+	{
+		$quantity = floor($quantity);
+		return apply_filters(
+			'FHEE__EEM_Base__item_name__plural_or_singular',
+			$quantity > 1 ? $this->plural_item : $this->singular_item,
+			$quantity,
+			$this->plural_item,
+			$this->singular_item
+		);
+	}
+
+
+	/**
+	 * Very handy general function to allow for plugins to extend any child of EE_TempBase.
+	 * If a method is called on a child of EE_TempBase that doesn't exist, this function is called
+	 * (http://www.garfieldtech.com/blog/php-magic-call) and passed the method's name and arguments. Instead of
+	 * requiring a plugin to extend the EE_TempBase (which works fine is there's only 1 plugin, but when will that
+	 * happen?) they can add a hook onto 'filters_hook_espresso__{className}__{methodName}' (eg,
+	 * filters_hook_espresso__EE_Answer__my_great_function) and accepts 2 arguments: the object on which the function
+	 * was called, and an array of the original arguments passed to the function. Whatever their callback function
+	 * returns will be returned by this function. Example: in functions.php (or in a plugin):
+	 * add_filter('FHEE__EE_Answer__my_callback','my_callback',10,3); function
+	 * my_callback($previousReturnValue,EE_TempBase $object,$argsArray){
+	 * $returnString= "you called my_callback! and passed args:".implode(",",$argsArray);
+	 *        return $previousReturnValue.$returnString;
+	 * }
+	 * require('EEM_Answer.model.php');
+	 * echo EEM_Answer::instance()->my_callback('monkeys',100);
+	 * // will output "you called my_callback! and passed args:monkeys,100"
+	 *
+	 * @param string $methodName name of method which was called on a child of EE_TempBase, but which
+	 * @param array  $args       array of original arguments passed to the function
+	 * @return mixed whatever the plugin which calls add_filter decides
+	 * @throws EE_Error
+	 */
+	public function __call($methodName, $args)
+	{
+		$className = get_class($this);
+		$tagName   = "FHEE__{$className}__{$methodName}";
+		if (! has_filter($tagName)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'Method %1$s on model %2$s does not exist! You can create one with the following code in functions.php or in a plugin: %4$s function my_callback(%4$s \$previousReturnValue, EEM_Base \$object\ $argsArray=NULL ){%4$s     /*function body*/%4$s      return \$whatever;%4$s }%4$s add_filter( \'%3$s\', \'my_callback\', 10, 3 );',
+						'event_espresso'
+					),
+					$methodName,
+					$className,
+					$tagName,
+					'<br />'
+				)
+			);
+		}
+		return apply_filters($tagName, null, $this, $args);
+	}
+
+
+	/**
+	 * Ensures $base_class_obj_or_id is of the EE_Base_Class child that corresponds ot this model.
+	 * If not, assumes its an ID, and uses $this->get_one_by_ID() to get the EE_Base_Class.
+	 *
+	 * @param EE_Base_Class|string|int $base_class_obj_or_id either:
+	 *                                                       the EE_Base_Class object that corresponds to this Model,
+	 *                                                       the object's class name
+	 *                                                       or object's ID
+	 * @param boolean                  $ensure_is_in_db      if set, we will also verify this model object
+	 *                                                       exists in the database. If it does not, we add it
+	 * @return EE_Base_Class
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function ensure_is_obj($base_class_obj_or_id, $ensure_is_in_db = false)
+	{
+		$className = $this->_get_class_name();
+		if ($base_class_obj_or_id instanceof $className) {
+			$model_object = $base_class_obj_or_id;
+		} else {
+			$primary_key_field = $this->get_primary_key_field();
+			if (
+				$primary_key_field instanceof EE_Primary_Key_Int_Field
+				&& (
+					is_int($base_class_obj_or_id)
+					|| is_string($base_class_obj_or_id)
+				)
+			) {
+				// assume it's an ID.
+				// either a proper integer or a string representing an integer (eg "101" instead of 101)
+				$model_object = $this->get_one_by_ID($base_class_obj_or_id);
+			} elseif (
+				$primary_key_field instanceof EE_Primary_Key_String_Field
+				&& is_string($base_class_obj_or_id)
+			) {
+				// assume its a string representation of the object
+				$model_object = $this->get_one_by_ID($base_class_obj_or_id);
+			} else {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							"'%s' is neither an object of type %s, nor an ID! Its full value is '%s'",
+							'event_espresso'
+						),
+						$base_class_obj_or_id,
+						$this->_get_class_name(),
+						print_r($base_class_obj_or_id, true)
+					)
+				);
+			}
+		}
+		if ($ensure_is_in_db && $model_object->ID() !== null) {
+			$model_object->save();
+		}
+		return $model_object;
+	}
+
+
+	/**
+	 * Similar to ensure_is_obj(), this method makes sure $base_class_obj_or_id
+	 * is a value of the this model's primary key. If it's an EE_Base_Class child,
+	 * returns it ID.
+	 *
+	 * @param EE_Base_Class|int|string $base_class_obj_or_id
+	 * @return int|string depending on the type of this model object's ID
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function ensure_is_ID($base_class_obj_or_id)
+	{
+		$className = $this->_get_class_name();
+		if ($base_class_obj_or_id instanceof $className) {
+			/** @var $base_class_obj_or_id EE_Base_Class */
+			$id = $base_class_obj_or_id->ID();
+		} elseif (is_int($base_class_obj_or_id)) {
+			// assume it's an ID
+			$id = $base_class_obj_or_id;
+		} elseif (is_string($base_class_obj_or_id)) {
+			// assume its a string representation of the object
+			$id = $base_class_obj_or_id;
+		} else {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"'%s' is neither an object of type %s, nor an ID! Its full value is '%s'",
+						'event_espresso'
+					),
+					$base_class_obj_or_id,
+					$this->_get_class_name(),
+					print_r($base_class_obj_or_id, true)
+				)
+			);
+		}
+		return $id;
+	}
+
+
+	/**
+	 * Sets whether the values passed to the model (eg, values in WHERE, values in INSERT, UPDATE, etc)
+	 * have already been ran through the appropriate model field's prepare_for_use_in_db method. IE, they have
+	 * been sanitized and converted into the appropriate domain.
+	 * Usually the only place you'll want to change the default (which is to assume values have NOT been sanitized by
+	 * the model object/model field) is when making a method call from WITHIN a model object, which has direct access
+	 * to its sanitized values. Note: after changing this setting, you should set it back to its previous value (using
+	 * get_assumption_concerning_values_already_prepared_by_model_object()) eg.
+	 * $EVT = EEM_Event::instance(); $old_setting =
+	 * $EVT->get_assumption_concerning_values_already_prepared_by_model_object();
+	 * $EVT->assume_values_already_prepared_by_model_object(true);
+	 * $EVT->update(array('foo'=>'bar'),array(array('foo'=>'monkey')));
+	 * $EVT->assume_values_already_prepared_by_model_object($old_setting);
+	 *
+	 * @param int $values_already_prepared like one of the constants on EEM_Base
+	 * @return void
+	 */
+	public function assume_values_already_prepared_by_model_object(
+		$values_already_prepared = self::not_prepared_by_model_object
+	) {
+		$this->_values_already_prepared_by_model_object = $values_already_prepared;
+	}
+
+
+	/**
+	 * Read comments for assume_values_already_prepared_by_model_object()
+	 *
+	 * @return int
+	 */
+	public function get_assumption_concerning_values_already_prepared_by_model_object()
+	{
+		return $this->_values_already_prepared_by_model_object;
+	}
+
+
+	/**
+	 * Gets all the indexes on this model
+	 *
+	 * @return EE_Index[]
+	 */
+	public function indexes()
+	{
+		return $this->_indexes;
+	}
+
+
+	/**
+	 * Gets all the Unique Indexes on this model
+	 *
+	 * @return EE_Unique_Index[]
+	 */
+	public function unique_indexes()
+	{
+		$unique_indexes = [];
+		foreach ($this->_indexes as $name => $index) {
+			if ($index instanceof EE_Unique_Index) {
+				$unique_indexes [ $name ] = $index;
+			}
+		}
+		return $unique_indexes;
+	}
+
+
+	/**
+	 * Gets all the fields which, when combined, make the primary key.
+	 * This is usually just an array with 1 element (the primary key), but in cases
+	 * where there is no primary key, it's a combination of fields as defined
+	 * on a primary index
+	 *
+	 * @return EE_Model_Field_Base[] indexed by the field's name
+	 * @throws EE_Error
+	 */
+	public function get_combined_primary_key_fields()
+	{
+		foreach ($this->indexes() as $index) {
+			if ($index instanceof EE_Primary_Key_Index) {
+				return $index->fields();
+			}
+		}
+		return [$this->primary_key_name() => $this->get_primary_key_field()];
+	}
+
+
+	/**
+	 * Used to build a primary key string (when the model has no primary key),
+	 * which can be used a unique string to identify this model object.
+	 *
+	 * @param array $fields_n_values keys are field names, values are their values.
+	 *                               Note: if you have results from `EEM_Base::get_all_wpdb_results()`, you need to
+	 *                               run it through `EEM_Base::deduce_fields_n_values_from_cols_n_values()`
+	 *                               before passing it to this function (that will convert it from columns-n-values
+	 *                               to field-names-n-values).
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function get_index_primary_key_string($fields_n_values)
+	{
+		$cols_n_values_for_primary_key_index = array_intersect_key(
+			$fields_n_values,
+			$this->get_combined_primary_key_fields()
+		);
+		return http_build_query($cols_n_values_for_primary_key_index);
+	}
+
+
+	/**
+	 * Gets the field values from the primary key string
+	 *
+	 * @param string $index_primary_key_string
+	 * @return null|array
+	 * @throws EE_Error
+	 * @see EEM_Base::get_combined_primary_key_fields() and EEM_Base::get_index_primary_key_string()
+	 */
+	public function parse_index_primary_key_string($index_primary_key_string)
+	{
+		$key_fields = $this->get_combined_primary_key_fields();
+		// check all of them are in the $id
+		$key_vals_in_combined_pk = [];
+		parse_str($index_primary_key_string, $key_vals_in_combined_pk);
+		foreach ($key_fields as $key_field_name => $field_obj) {
+			if (! isset($key_vals_in_combined_pk[ $key_field_name ])) {
+				return null;
+			}
+		}
+		return $key_vals_in_combined_pk;
+	}
+
+
+	/**
+	 * verifies that an array of key-value pairs for model fields has a key
+	 * for each field comprising the primary key index
+	 *
+	 * @param array $key_vals
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function has_all_combined_primary_key_fields($key_vals)
+	{
+		$keys_it_should_have = array_keys($this->get_combined_primary_key_fields());
+		foreach ($keys_it_should_have as $key) {
+			if (! isset($key_vals[ $key ])) {
+				return false;
+			}
+		}
+		return true;
+	}
+
+
+	/**
+	 * Finds all model objects in the DB that appear to be a copy of $model_object_or_attributes_array.
+	 * We consider something to be a copy if all the attributes match (except the ID, of course).
+	 *
+	 * @param array|EE_Base_Class $model_object_or_attributes_array If its an array, it's field-value pairs
+	 * @param array               $query_params                     @see
+	 *                                                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @return EE_Base_Class[] Array keys are object IDs (if there is a primary key on the model. if not, numerically
+	 *                                                              indexed)
+	 */
+	public function get_all_copies($model_object_or_attributes_array, $query_params = [])
+	{
+		if ($model_object_or_attributes_array instanceof EE_Base_Class) {
+			$attributes_array = $model_object_or_attributes_array->model_field_array();
+		} elseif (is_array($model_object_or_attributes_array)) {
+			$attributes_array = $model_object_or_attributes_array;
+		} else {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"get_all_copies should be provided with either a model object or an array of field-value-pairs, but was given %s",
+						"event_espresso"
+					),
+					$model_object_or_attributes_array
+				)
+			);
+		}
+		// even copies obviously won't have the same ID, so remove the primary key
+		// from the WHERE conditions for finding copies (if there is a primary key, of course)
+		if ($this->has_primary_key_field() && isset($attributes_array[ $this->primary_key_name() ])) {
+			unset($attributes_array[ $this->primary_key_name() ]);
+		}
+		if (isset($query_params[0])) {
+			$query_params[0] = array_merge($attributes_array, $query_params);
+		} else {
+			$query_params[0] = $attributes_array;
+		}
+		return $this->get_all($query_params);
+	}
+
+
+	/**
+	 * Gets the first copy we find. See get_all_copies for more details
+	 *
+	 * @param mixed EE_Base_Class | array        $model_object_or_attributes_array
+	 * @param array $query_params
+	 * @return EE_Base_Class
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_one_copy($model_object_or_attributes_array, $query_params = [])
+	{
+		if (! is_array($query_params)) {
+			EE_Error::doing_it_wrong(
+				'EEM_Base::get_one_copy',
+				sprintf(
+					esc_html__('$query_params should be an array, you passed a variable of type %s', 'event_espresso'),
+					gettype($query_params)
+				),
+				'4.6.0'
+			);
+			$query_params = [];
+		}
+		$query_params['limit'] = 1;
+		$copies                = $this->get_all_copies($model_object_or_attributes_array, $query_params);
+		if (is_array($copies)) {
+			return array_shift($copies);
+		}
+		return null;
+	}
+
+
+	/**
+	 * Updates the item with the specified id. Ignores default query parameters because
+	 * we have specified the ID, and its assumed we KNOW what we're doing
+	 *
+	 * @param array      $fields_n_values keys are field names, values are their new values
+	 * @param int|string $id              the value of the primary key to update
+	 * @return int number of rows updated
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function update_by_ID($fields_n_values, $id)
+	{
+		$query_params = [
+			0                          => [$this->get_primary_key_field()->get_name() => $id],
+			'default_where_conditions' => EEM_Base::default_where_conditions_others_only,
+		];
+		return $this->update($fields_n_values, $query_params);
+	}
+
+
+	/**
+	 * Changes an operator which was supplied to the models into one usable in SQL
+	 *
+	 * @param string $operator_supplied
+	 * @return string an operator which can be used in SQL
+	 * @throws EE_Error
+	 */
+	private function _prepare_operator_for_sql($operator_supplied)
+	{
+		$sql_operator = $this->_valid_operators[ $operator_supplied ] ?? null;
+		if ($sql_operator) {
+			return $sql_operator;
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					"The operator '%s' is not in the list of valid operators: %s",
+					"event_espresso"
+				),
+				$operator_supplied,
+				implode(",", array_keys($this->_valid_operators))
+			)
+		);
+	}
+
+
+	/**
+	 * Gets the valid operators
+	 *
+	 * @return array keys are accepted strings, values are the SQL they are converted to
+	 */
+	public function valid_operators()
+	{
+		return $this->_valid_operators;
+	}
+
+
+	/**
+	 * Gets the between-style operators (take 2 arguments).
+	 *
+	 * @return array keys are accepted strings, values are the SQL they are converted to
+	 */
+	public function valid_between_style_operators()
+	{
+		return array_intersect(
+			$this->valid_operators(),
+			$this->_between_style_operators
+		);
+	}
+
+
+	/**
+	 * Gets the "like"-style operators (take a single argument, but it may contain wildcards)
+	 *
+	 * @return array keys are accepted strings, values are the SQL they are converted to
+	 */
+	public function valid_like_style_operators()
+	{
+		return array_intersect(
+			$this->valid_operators(),
+			$this->_like_style_operators
+		);
+	}
+
+
+	/**
+	 * Gets the "in"-style operators
+	 *
+	 * @return array keys are accepted strings, values are the SQL they are converted to
+	 */
+	public function valid_in_style_operators()
+	{
+		return array_intersect(
+			$this->valid_operators(),
+			$this->_in_style_operators
+		);
+	}
+
+
+	/**
+	 * Gets the "null"-style operators (accept no arguments)
+	 *
+	 * @return array keys are accepted strings, values are the SQL they are converted to
+	 */
+	public function valid_null_style_operators()
+	{
+		return array_intersect(
+			$this->valid_operators(),
+			$this->_null_style_operators
+		);
+	}
+
+
+	/**
+	 * Gets an array where keys are the primary keys and values are their 'names'
+	 * (as determined by the model object's name() function, which is often overridden)
+	 *
+	 * @param array $query_params like get_all's
+	 * @return string[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_all_names($query_params = [])
+	{
+		$objs  = $this->get_all($query_params);
+		$names = [];
+		foreach ($objs as $obj) {
+			$names[ $obj->ID() ] = $obj->name();
+		}
+		return $names;
+	}
+
+
+	/**
+	 * Gets an array of primary keys from the model objects. If you acquired the model objects
+	 * using EEM_Base::get_all() you don't need to call this (and probably shouldn't because
+	 * this is duplicated effort and reduces efficiency) you would be better to use
+	 * array_keys() on $model_objects.
+	 *
+	 * @param \EE_Base_Class[] $model_objects
+	 * @param boolean          $filter_out_empty_ids if a model object has an ID of '' or 0, don't bother including it
+	 *                                               in the returned array
+	 * @return array
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_IDs($model_objects, $filter_out_empty_ids = false)
+	{
+		if (! $this->has_primary_key_field()) {
+			if (WP_DEBUG) {
+				EE_Error::add_error(
+					esc_html__('Trying to get IDs from a model than has no primary key', 'event_espresso'),
+					__FILE__,
+					__FUNCTION__,
+					__LINE__
+				);
+			}
+		}
+		$IDs = [];
+		foreach ($model_objects as $model_object) {
+			$id = $model_object->ID();
+			if (! $id) {
+				if ($filter_out_empty_ids) {
+					continue;
+				}
+				if (WP_DEBUG) {
+					EE_Error::add_error(
+						esc_html__(
+							'Called %1$s on a model object that has no ID and so probably hasn\'t been saved to the database',
+							'event_espresso'
+						),
+						__FILE__,
+						__FUNCTION__,
+						__LINE__
+					);
+				}
+			}
+			$IDs[] = $id;
+		}
+		return $IDs;
+	}
+
+
+	/**
+	 * Returns the string used in capabilities relating to this model. If there
+	 * are no capabilities that relate to this model returns false
+	 *
+	 * @return string|false
+	 */
+	public function cap_slug()
+	{
+		return apply_filters('FHEE__EEM_Base__cap_slug', $this->_caps_slug, $this);
+	}
+
+
+	/**
+	 * Returns the capability-restrictions array (@param string $context
+	 *
+	 * @return EE_Default_Where_Conditions[] indexed by associated capability
+	 * @throws EE_Error
+	 * @see EEM_Base::_cap_restrictions).
+	 *      If $context is provided (which should be set to one of EEM_Base::valid_cap_contexts())
+	 *      only returns the cap restrictions array in that context (ie, the array
+	 *      at that key)
+	 *
+	 */
+	public function cap_restrictions($context = EEM_Base::caps_read)
+	{
+		EEM_Base::verify_is_valid_cap_context($context);
+		// check if we ought to run the restriction generator first
+		if (
+			isset($this->_cap_restriction_generators[ $context ])
+			&& $this->_cap_restriction_generators[ $context ] instanceof EE_Restriction_Generator_Base
+			&& ! $this->_cap_restriction_generators[ $context ]->has_generated_cap_restrictions()
+		) {
+			$this->_cap_restrictions[ $context ] = array_merge(
+				$this->_cap_restrictions[ $context ],
+				$this->_cap_restriction_generators[ $context ]->generate_restrictions()
+			);
+		}
+		// and make sure we've finalized the construction of each restriction
+		foreach ($this->_cap_restrictions[ $context ] as $where_conditions_obj) {
+			if ($where_conditions_obj instanceof EE_Default_Where_Conditions) {
+				$where_conditions_obj->_finalize_construct($this);
+			}
+		}
+		return $this->_cap_restrictions[ $context ];
+	}
+
+
+	/**
+	 * Indicating whether or not this model thinks its a wp core model
+	 *
+	 * @return boolean
+	 */
+	public function is_wp_core_model()
+	{
+		return $this->_wp_core_model;
+	}
+
+
+	/**
+	 * Gets all the caps that are missing which impose a restriction on
+	 * queries made in this context
+	 *
+	 * @param string $context one of EEM_Base::caps_ constants
+	 * @return EE_Default_Where_Conditions[] indexed by capability name
+	 * @throws EE_Error
+	 */
+	public function caps_missing($context = EEM_Base::caps_read)
+	{
+		$missing_caps     = [];
+		$cap_restrictions = $this->cap_restrictions($context);
+		foreach ($cap_restrictions as $cap => $restriction_if_no_cap) {
+			if (
+				! EE_Capabilities::instance()
+								 ->current_user_can($cap, $this->get_this_model_name() . '_model_applying_caps')
+			) {
+				$missing_caps[ $cap ] = $restriction_if_no_cap;
+			}
+		}
+		return $missing_caps;
+	}
+
+
+	/**
+	 * Gets the mapping from capability contexts to action strings used in capability names
+	 *
+	 * @return array keys are one of EEM_Base::valid_cap_contexts(), and values are usually
+	 * one of 'read', 'edit', or 'delete'
+	 */
+	public function cap_contexts_to_cap_action_map()
+	{
+		return apply_filters(
+			'FHEE__EEM_Base__cap_contexts_to_cap_action_map',
+			$this->_cap_contexts_to_cap_action_map,
+			$this
+		);
+	}
+
+
+	/**
+	 * Gets the action string for the specified capability context
+	 *
+	 * @param string $context
+	 * @return string one of EEM_Base::cap_contexts_to_cap_action_map() values
+	 * @throws EE_Error
+	 */
+	public function cap_action_for_context($context)
+	{
+		$mapping = $this->cap_contexts_to_cap_action_map();
+		if (isset($mapping[ $context ])) {
+			return $mapping[ $context ];
+		}
+		if ($action = apply_filters('FHEE__EEM_Base__cap_action_for_context', null, $this, $mapping, $context)) {
+			return $action;
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					'Cannot find capability restrictions for context "%1$s", allowed values are:%2$s',
+					'event_espresso'
+				),
+				$context,
+				implode(',', array_keys($this->cap_contexts_to_cap_action_map()))
+			)
+		);
+	}
+
+
+	/**
+	 * Returns all the capability contexts which are valid when querying models
+	 *
+	 * @return array
+	 */
+	public static function valid_cap_contexts()
+	{
+		return apply_filters('FHEE__EEM_Base__valid_cap_contexts', [
+			self::caps_read,
+			self::caps_read_admin,
+			self::caps_edit,
+			self::caps_delete,
+		]);
+	}
+
+
+	/**
+	 * Returns all valid options for 'default_where_conditions'
+	 *
+	 * @return array
+	 */
+	public static function valid_default_where_conditions()
+	{
+		return [
+			EEM_Base::default_where_conditions_all,
+			EEM_Base::default_where_conditions_this_only,
+			EEM_Base::default_where_conditions_others_only,
+			EEM_Base::default_where_conditions_minimum_all,
+			EEM_Base::default_where_conditions_minimum_others,
+			EEM_Base::default_where_conditions_none,
+		];
+	}
+
+	// public static function default_where_conditions_full
+
+
+	/**
+	 * Verifies $context is one of EEM_Base::valid_cap_contexts(), if not it throws an exception
+	 *
+	 * @param string $context
+	 * @return bool
+	 * @throws EE_Error
+	 */
+	public static function verify_is_valid_cap_context($context)
+	{
+		$valid_cap_contexts = EEM_Base::valid_cap_contexts();
+		if (in_array($context, $valid_cap_contexts)) {
+			return true;
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					'Context "%1$s" passed into model "%2$s" is not a valid context. They are: %3$s',
+					'event_espresso'
+				),
+				$context,
+				'EEM_Base',
+				implode(',', $valid_cap_contexts)
+			)
+		);
+	}
+
+
+	/**
+	 * Clears all the models field caches. This is only useful when a sub-class
+	 * might have added a field or something and these caches might be invalidated
+	 */
+	protected function _invalidate_field_caches()
+	{
+		$this->_cache_foreign_key_to_fields = [];
+		$this->_cached_fields               = null;
+		$this->_cached_fields_non_db_only   = null;
+	}
+
+
+	/**
+	 * Gets the list of all the where query param keys that relate to logic instead of field names
+	 * (eg "and", "or", "not").
+	 *
+	 * @return array
+	 */
+	public function logic_query_param_keys()
+	{
+		return $this->_logic_query_param_keys;
+	}
+
+
+	/**
+	 * Determines whether or not the where query param array key is for a logic query param.
+	 * Eg 'OR', 'not*', and 'and*because-i-say-so' should all return true, whereas
+	 * 'ATT_fname', 'EVT_name*not-you-or-me', and 'ORG_name' should return false
+	 *
+	 * @param $query_param_key
+	 * @return bool
+	 */
+	public function is_logic_query_param_key($query_param_key)
+	{
+		foreach ($this->logic_query_param_keys() as $logic_query_param_key) {
+			if (
+				$query_param_key === $logic_query_param_key
+				|| strpos($query_param_key, $logic_query_param_key . '*') === 0
+			) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+
+	/**
+	 * Returns true if this model has a password field on it (regardless of whether that password field has any content)
+	 *
+	 * @return boolean
+	 * @since 4.9.74.p
+	 */
+	public function hasPassword()
+	{
+		// if we don't yet know if there's a password field, find out and remember it for next time.
+		if ($this->has_password_field === null) {
+			$password_field           = $this->getPasswordField();
+			$this->has_password_field = $password_field instanceof EE_Password_Field ? true : false;
+		}
+		return $this->has_password_field;
+	}
+
+
+	/**
+	 * Returns the password field on this model, if there is one
+	 *
+	 * @return EE_Password_Field|null
+	 * @since 4.9.74.p
+	 */
+	public function getPasswordField()
+	{
+		// if we definetely already know there is a password field or not (because has_password_field is true or false)
+		// there's no need to search for it. If we don't know yet, then find out
+		if ($this->has_password_field === null && $this->password_field === null) {
+			$this->password_field = $this->get_a_field_of_type('EE_Password_Field');
+		}
+		// don't bother setting has_password_field because that's hasPassword()'s job.
+		return $this->password_field;
+	}
+
+
+	/**
+	 * Returns the list of field (as EE_Model_Field_Bases) that are protected by the password
+	 *
+	 * @return EE_Model_Field_Base[]
+	 * @throws EE_Error
+	 * @since 4.9.74.p
+	 */
+	public function getPasswordProtectedFields()
+	{
+		$password_field = $this->getPasswordField();
+		$fields         = [];
+		if ($password_field instanceof EE_Password_Field) {
+			$field_names = $password_field->protectedFields();
+			foreach ($field_names as $field_name) {
+				$fields[ $field_name ] = $this->field_settings_for($field_name);
+			}
+		}
+		return $fields;
+	}
+
+
+	/**
+	 * Checks if the current user can perform the requested action on this model
+	 *
+	 * @param string              $cap_to_check one of the array keys from _cap_contexts_to_cap_action_map
+	 * @param EE_Base_Class|array $model_obj_or_fields_n_values
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws UnexpectedEntityException
+	 * @since 4.9.74.p
+	 */
+	public function currentUserCan($cap_to_check, $model_obj_or_fields_n_values)
+	{
+		if ($model_obj_or_fields_n_values instanceof EE_Base_Class) {
+			$model_obj_or_fields_n_values = $model_obj_or_fields_n_values->model_field_array();
+		}
+		if (! is_array($model_obj_or_fields_n_values)) {
+			throw new UnexpectedEntityException(
+				$model_obj_or_fields_n_values,
+				'EE_Base_Class',
+				sprintf(
+					esc_html__(
+						'%1$s must be passed an `EE_Base_Class or an array of fields names with their values. You passed in something different.',
+						'event_espresso'
+					),
+					__FUNCTION__
+				)
+			);
+		}
+		return $this->exists(
+			$this->alter_query_params_to_restrict_by_ID(
+				$this->get_index_primary_key_string($model_obj_or_fields_n_values),
+				[
+					'default_where_conditions' => 'none',
+					'caps'                     => $cap_to_check,
+				]
+			)
+		);
+	}
+
+
+	/**
+	 * Returns the query param where conditions key to the password affecting this model.
+	 * Eg on EEM_Event this would just be "password", on EEM_Datetime this would be "Event.password", etc.
+	 *
+	 * @return null|string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ModelConfigurationException
+	 * @throws ReflectionException
+	 * @since 4.9.74.p
+	 */
+	public function modelChainAndPassword()
+	{
+		if ($this->model_chain_to_password === null) {
+			throw new ModelConfigurationException(
+				$this,
+				esc_html_x(
+				// @codingStandardsIgnoreStart
+					'Cannot exclude protected data because the model has not specified which model has the password.',
+					// @codingStandardsIgnoreEnd
+					'1: model name',
+					'event_espresso'
+				)
+			);
+		}
+		if ($this->model_chain_to_password === '') {
+			$model_with_password = $this;
+		} else {
+			if ($pos_of_period = strrpos($this->model_chain_to_password, '.')) {
+				$last_model_in_chain = substr($this->model_chain_to_password, $pos_of_period + 1);
+			} else {
+				$last_model_in_chain = $this->model_chain_to_password;
+			}
+			$model_with_password = EE_Registry::instance()->load_model($last_model_in_chain);
+		}
+
+		$password_field = $model_with_password->getPasswordField();
+		if ($password_field instanceof EE_Password_Field) {
+			$password_field_name = $password_field->get_name();
+		} else {
+			throw new ModelConfigurationException(
+				$this,
+				sprintf(
+					esc_html_x(
+						'This model claims related model "%1$s" should have a password field on it, but none was found. The model relation chain is "%2$s"',
+						'1: model name, 2: special string',
+						'event_espresso'
+					),
+					$model_with_password->get_this_model_name(),
+					$this->model_chain_to_password
+				)
+			);
+		}
+		return ($this->model_chain_to_password ? $this->model_chain_to_password . '.' : '') . $password_field_name;
+	}
+
+
+	/**
+	 * Returns true if there is a password on a related model which restricts access to some of this model's rows,
+	 * or if this model itself has a password affecting access to some of its other fields.
+	 *
+	 * @return boolean
+	 * @since 4.9.74.p
+	 */
+	public function restrictedByRelatedModelPassword()
+	{
+		return $this->model_chain_to_password !== null;
+	}
 }

core/domain/entities/editor/CoreBlocksAssetManager.php

Indentation +27 added lines, -27 removed lines

@@ -16,31 +16,31 @@
  */
 class CoreBlocksAssetManager extends BlockAssetManager
 {
-    const DOMAIN = 'blocks';
-
-    const ASSET_HANDLE_EDITOR_BLOCKS = Domain::ASSET_NAMESPACE . '-' . CoreBlocksAssetManager::DOMAIN;
-    const ASSET_HANDLE_CORE_BLOCKS = '';
-
-
-    /**
-     * @since  $VID:$
-     * @throws DomainException
-     */
-    public function enqueueEventEditor()
-    {
-        if ($this->verifyAssetIsRegistered(CoreBlocksAssetManager::ASSET_HANDLE_EDITOR_BLOCKS)) {
-            wp_enqueue_script(CoreBlocksAssetManager::ASSET_HANDLE_EDITOR_BLOCKS);
-            wp_enqueue_style(CoreBlocksAssetManager::ASSET_HANDLE_EDITOR_BLOCKS);
-        }
-    }
-
-
-    /**
-     * @since 4.9.71.p
-     */
-    public function setAssetHandles()
-    {
-        $this->setEditorScriptHandle(CoreBlocksAssetManager::ASSET_HANDLE_EDITOR_BLOCKS);
-        $this->setScriptHandle(CoreBlocksAssetManager::ASSET_HANDLE_CORE_BLOCKS);
-    }
+	const DOMAIN = 'blocks';
+
+	const ASSET_HANDLE_EDITOR_BLOCKS = Domain::ASSET_NAMESPACE . '-' . CoreBlocksAssetManager::DOMAIN;
+	const ASSET_HANDLE_CORE_BLOCKS = '';
+
+
+	/**
+	 * @since  $VID:$
+	 * @throws DomainException
+	 */
+	public function enqueueEventEditor()
+	{
+		if ($this->verifyAssetIsRegistered(CoreBlocksAssetManager::ASSET_HANDLE_EDITOR_BLOCKS)) {
+			wp_enqueue_script(CoreBlocksAssetManager::ASSET_HANDLE_EDITOR_BLOCKS);
+			wp_enqueue_style(CoreBlocksAssetManager::ASSET_HANDLE_EDITOR_BLOCKS);
+		}
+	}
+
+
+	/**
+	 * @since 4.9.71.p
+	 */
+	public function setAssetHandles()
+	{
+		$this->setEditorScriptHandle(CoreBlocksAssetManager::ASSET_HANDLE_EDITOR_BLOCKS);
+		$this->setScriptHandle(CoreBlocksAssetManager::ASSET_HANDLE_CORE_BLOCKS);
+	}
 }

core/db_classes/EE_CPT_Base.class.php

Indentation +440 added lines, -440 removed lines

@@ -13,444 +13,444 @@
  */
 abstract class EE_CPT_Base extends EE_Soft_Delete_Base_Class
 {
-    /**
-     * @var stdClass
-     * @since $VID:$
-     */
-    public $labels;
-
-    /**
-     * @var string
-     * @since $VID:$
-     */
-    public $name;
-
-    /**
-     * This is a property for holding cached feature images on CPT objects.  Cache's are set on the first
-     * "feature_image()" method call.  Each key in the array corresponds to the requested size.
-     *
-     * @var array
-     */
-    protected $_feature_image = array();
-
-    /**
-     * @var WP_Post the WP_Post that corresponds with this CPT model object
-     */
-    protected $_wp_post;
-
-
-    abstract public function wp_user();
-
-
-    /**
-     * Returns the WP post associated with this CPT model object. If this CPT is saved, fetches it
-     * from the DB. Otherwise, create an unsaved WP_POst object. Caches the post internally.
-     *
-     * @return WP_Post
-     */
-    public function wp_post()
-    {
-        global $wpdb;
-        if (! $this->_wp_post instanceof WP_Post) {
-            if ($this->ID()) {
-                $this->_wp_post = get_post($this->ID());
-            } else {
-                $simulated_db_result = new stdClass();
-                foreach ($this->get_model()->field_settings(true) as $field_name => $field_obj) {
-                    if (
-                        $this->get_model()->get_table_obj_by_alias($field_obj->get_table_alias())->get_table_name()
-                        === $wpdb->posts
-                    ) {
-                        $column = $field_obj->get_table_column();
-
-                        if ($field_obj instanceof EE_Datetime_Field) {
-                            $value_on_model_obj = $this->get_DateTime_object($field_name);
-                        } elseif ($field_obj->is_db_only_field()) {
-                            $value_on_model_obj = $field_obj->get_default_value();
-                        } else {
-                            $value_on_model_obj = $this->get_raw($field_name);
-                        }
-                        $simulated_db_result->{$column} = $field_obj->prepare_for_use_in_db($value_on_model_obj);
-                    }
-                }
-                $this->_wp_post = new WP_Post($simulated_db_result);
-            }
-            // and let's make retrieving the EE CPT object easy too
-            $classname = get_class($this);
-            if (! isset($this->_wp_post->{$classname})) {
-                $this->_wp_post->{$classname} = $this;
-            }
-        }
-        return $this->_wp_post;
-    }
-
-    /**
-     * When fetching a new value for a post field that uses the global $post for rendering,
-     * set the global $post temporarily to be this model object; and afterwards restore it
-     *
-     * @param string $fieldname
-     * @param bool   $pretty
-     * @param string $extra_cache_ref
-     * @return mixed
-     */
-    protected function _get_fresh_property($fieldname, $pretty = false, $extra_cache_ref = null)
-    {
-        global $post;
-
-        if (
-            $pretty
-            && (
-                ! (
-                    $post instanceof WP_Post
-                    && $post->ID
-                )
-                || (int) $post->ID !== $this->ID()
-            )
-            && $this->get_model()->field_settings_for($fieldname) instanceof EE_Post_Content_Field
-        ) {
-            $old_post = $post;
-            $post = $this->wp_post();
-            $return_value = parent::_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
-            $post = $old_post;
-        } else {
-            $return_value = parent::_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
-        }
-        return $return_value;
-    }
-
-    /**
-     * Adds to the specified event category. If it category doesn't exist, creates it.
-     *
-     * @param string $category_name
-     * @param string $category_description    optional
-     * @param int    $parent_term_taxonomy_id optional
-     * @return EE_Term_Taxonomy
-     */
-    public function add_event_category($category_name, $category_description = null, $parent_term_taxonomy_id = null)
-    {
-        return $this->get_model()->add_event_category(
-            $this,
-            $category_name,
-            $category_description,
-            $parent_term_taxonomy_id
-        );
-    }
-
-
-    /**
-     * Removes the event category by specified name from being related ot this event
-     *
-     * @param string $category_name
-     * @return bool
-     */
-    public function remove_event_category($category_name)
-    {
-        return $this->get_model()->remove_event_category($this, $category_name);
-    }
-
-
-    /**
-     * Removes the relation to the specified term taxonomy, and maintains the
-     * data integrity of the term taxonomy provided
-     *
-     * @param EE_Term_Taxonomy $term_taxonomy
-     * @return EE_Base_Class the relation was removed from
-     */
-    public function remove_relation_to_term_taxonomy($term_taxonomy)
-    {
-        if (! $term_taxonomy) {
-            EE_Error::add_error(
-                sprintf(
-                    esc_html__(
-                        "No Term_Taxonomy provided which to remove from model object of type %s and id %d",
-                        "event_espresso"
-                    ),
-                    get_class($this),
-                    $this->ID()
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return null;
-        }
-        $term_taxonomy->set_count($term_taxonomy->count() - 1);
-        $term_taxonomy->save();
-        return $this->_remove_relation_to($term_taxonomy, 'Term_Taxonomy');
-    }
-
-
-    /**
-     * The main purpose of this method is to return the post type for the model object
-     *
-     * @access public
-     * @return string
-     */
-    public function post_type()
-    {
-        return $this->get_model()->post_type();
-    }
-
-
-    /**
-     * The main purpose of this method is to return the parent for the model object
-     *
-     * @access public
-     * @return int
-     */
-    public function parent()
-    {
-        return $this->get('parent');
-    }
-
-
-    /**
-     * return the _status property
-     *
-     * @return string
-     */
-    public function status()
-    {
-        return $this->get('status');
-    }
-
-
-    /**
-     * @param string $status
-     */
-    public function set_status($status)
-    {
-        $this->set('status', $status);
-    }
-
-
-    /**
-     * This calls the equivalent model method for retrieving the feature image which in turn is a wrapper for
-     * WordPress' get_the_post_thumbnail() function.
-     *
-     * @link   http://codex.wordpress.org/Function_Reference/get_the_post_thumbnail
-     * @access protected
-     * @param string|array $size (optional) Image size. Defaults to 'post-thumbnail' but can also be a 2-item array
-     *                           representing width and height in pixels (i.e. array(32,32) ).
-     * @param string|array $attr Optional. Query string or array of attributes.
-     * @return string HTML image element
-     */
-    protected function _get_feature_image($size, $attr)
-    {
-        // first let's see if we already have the _feature_image property set AND if it has a cached element on it FOR the given size
-        $attr_key = is_array($attr) ? implode('_', $attr) : $attr;
-        $cache_key = is_array($size) ? implode('_', $size) . $attr_key : $size . $attr_key;
-        $this->_feature_image[ $cache_key ] = isset($this->_feature_image[ $cache_key ])
-            ? $this->_feature_image[ $cache_key ] : $this->get_model()->get_feature_image($this->ID(), $size, $attr);
-        return $this->_feature_image[ $cache_key ];
-    }
-
-
-    /**
-     * See _get_feature_image. Returns the HTML to display a featured image
-     *
-     * @param string       $size
-     * @param string|array $attr
-     * @return string of html
-     */
-    public function feature_image($size = 'thumbnail', $attr = '')
-    {
-        return $this->_get_feature_image($size, $attr);
-    }
-
-
-    /**
-     * This uses the wp "wp_get_attachment_image_src()" function to return the feature image for the current class
-     * using the given size params.
-     *
-     * @param  string|array $size can either be a string: 'thumbnail', 'medium', 'large', 'full' OR 2-item array
-     *                            representing width and height in pixels eg. array(32,32).
-     * @return string|boolean          the url of the image or false if not found
-     */
-    public function feature_image_url($size = 'thumbnail')
-    {
-        $attachment = wp_get_attachment_image_src(get_post_thumbnail_id($this->ID()), $size);
-        return ! empty($attachment) ? $attachment[0] : false;
-    }
-
-
-    /**
-     * This is a method for restoring this_obj using details from the given $revision_id
-     *
-     * @param int   $revision_id       ID of the revision we're getting data from
-     * @param array $related_obj_names if included this will be used to restore for related obj
-     *                                 if not included then we just do restore on the meta.
-     *                                 We will accept an array of related_obj_names for restoration here.
-     * @param array $where_query       You can optionally include an array of key=>value pairs
-     *                                 that allow you to further constrict the relation to being added.
-     *                                 However, keep in mind that the columns (keys) given
-     *                                 must match a column on the JOIN table and currently
-     *                                 only the HABTM models accept these additional conditions.
-     *                                 Also remember that if an exact match isn't found for these extra cols/val pairs,
-     *                                 then a NEW row is created in the join table.
-     *                                 This array is INDEXED by RELATED OBJ NAME (so it corresponds with the obj_names
-     *                                 sent);
-     * @return void
-     */
-    public function restore_revision($revision_id, $related_obj_names = array(), $where_query = array())
-    {
-        // get revision object
-        $revision_obj = $this->get_model()->get_one_by_ID($revision_id);
-        if ($revision_obj instanceof EE_CPT_Base) {
-            // no related_obj_name so we assume we're saving a revision on this object.
-            if (empty($related_obj_names)) {
-                $fields = $this->get_model()->get_meta_table_fields();
-                foreach ($fields as $field) {
-                    $this->set($field, $revision_obj->get($field));
-                }
-                $this->save();
-            }
-            $related_obj_names = (array) $related_obj_names;
-            foreach ($related_obj_names as $related_name) {
-                // related_obj_name so we're saving a revision on an object related to this object
-                // do we have $where_query params for this related object?  If we do then we include that.
-                $cols_n_values = isset($where_query[ $related_name ]) ? $where_query[ $related_name ] : array();
-                $where_params = ! empty($cols_n_values) ? array($cols_n_values) : array();
-                $related_objs = $this->get_many_related($related_name, $where_params);
-                $revision_related_objs = $revision_obj->get_many_related($related_name, $where_params);
-                // load helper
-                // remove related objs from this object that are not in revision
-                // array_diff *should* work cause I think objects are indexed by ID?
-                $related_to_remove = EEH_Array::object_array_diff($related_objs, $revision_related_objs);
-                foreach ($related_to_remove as $rr) {
-                    $this->_remove_relation_to($rr, $related_name, $cols_n_values);
-                }
-                // add all related objs attached to revision to this object
-                foreach ($revision_related_objs as $r_obj) {
-                    $this->_add_relation_to($r_obj, $related_name, $cols_n_values);
-                }
-            }
-        }
-    }
-
-
-    /**
-     * Wrapper for get_post_meta, http://codex.wordpress.org/Function_Reference/get_post_meta
-     *
-     * @param string  $meta_key
-     * @param boolean $single
-     * @return mixed <ul><li>If only $id is set it will return all meta values in an associative array.</li>
-     * <li>If $single is set to false, or left blank, the function returns an array containing all values of the
-     * specified key.</li>
-     * <li>If $single is set to true, the function returns the first value of the specified key (not in an
-     * array</li></ul>
-     */
-    public function get_post_meta($meta_key = null, $single = false)
-    {
-        return get_post_meta($this->ID(), $meta_key, $single);
-    }
-
-
-    /**
-     * Wrapper for update_post_meta, http://codex.wordpress.org/Function_Reference/update_post_meta
-     *
-     * @param string $meta_key
-     * @param mixed  $meta_value
-     * @param mixed  $prev_value
-     * @return mixed Returns meta_id if the meta doesn't exist, otherwise returns true on success and false on failure.
-     *               NOTE: If the meta_value passed to this function is the same as the value that is already in the
-     *               database, this function returns false.
-     */
-    public function update_post_meta($meta_key, $meta_value, $prev_value = null)
-    {
-        if (! $this->ID()) {
-            $this->save();
-        }
-        return update_post_meta($this->ID(), $meta_key, $meta_value, $prev_value);
-    }
-
-
-    /**
-     * Wrapper for add_post_meta, http://codex.wordpress.org/Function_Reference/add_post_meta
-     *
-     * @param mixed $meta_key
-     * @param mixed $meta_value
-     * @param bool  $unique . If postmeta for this $meta_key already exists, whether to add an additional item or not
-     * @return boolean Boolean true, except if the $unique argument was set to true and a custom field with the given
-     *                 key already exists, in which case false is returned.
-     */
-    public function add_post_meta($meta_key, $meta_value, $unique = false)
-    {
-        if ($this->ID()) {
-            $this->save();
-        }
-        return add_post_meta($this->ID(), $meta_key, $meta_value, $unique);
-    }
-
-
-    /**
-     * Wrapper for delete_post_meta, http://codex.wordpress.org/Function_Reference/delete_post_meta
-     *
-     * @param mixed $meta_key
-     * @param mixed $meta_value
-     * @return boolean False for failure. True for success.
-     */
-    public function delete_post_meta($meta_key, $meta_value = '')
-    {
-        if (! $this->ID()) {
-            // there are obviously no postmetas for this if it's not saved
-            // so let's just report this as a success
-            return true;
-        }
-        return delete_post_meta($this->ID(), $meta_key, $meta_value);
-    }
-
-
-    /**
-     * Gets the URL for viewing this event on the front-end
-     *
-     * @return string
-     */
-    public function get_permalink()
-    {
-        return get_permalink($this->ID());
-    }
-
-
-    /**
-     * Gets all the term-taxonomies for this CPT
-     *
-     * @param array $query_params
-     * @return EE_Term_Taxonomy
-     */
-    public function term_taxonomies($query_params = array())
-    {
-        return $this->get_many_related('Term_Taxonomy', $query_params);
-    }
-
-
-    /**
-     * @return mixed
-     */
-    public function get_custom_post_statuses()
-    {
-        return $this->get_model()->get_custom_post_statuses();
-    }
-
-
-    /**
-     * @return mixed
-     */
-    public function get_all_post_statuses()
-    {
-        return $this->get_model()->get_status_array();
-    }
-
-
-    /**
-     * Don't serialize the WP Post. That's just duplicate data and we want to avoid recursion
-     *
-     * @return array
-     */
-    public function __sleep()
-    {
-        $properties_to_serialize = parent::__sleep();
-        $properties_to_serialize = array_diff($properties_to_serialize, array('_wp_post'));
-        return $properties_to_serialize;
-    }
+	/**
+	 * @var stdClass
+	 * @since $VID:$
+	 */
+	public $labels;
+
+	/**
+	 * @var string
+	 * @since $VID:$
+	 */
+	public $name;
+
+	/**
+	 * This is a property for holding cached feature images on CPT objects.  Cache's are set on the first
+	 * "feature_image()" method call.  Each key in the array corresponds to the requested size.
+	 *
+	 * @var array
+	 */
+	protected $_feature_image = array();
+
+	/**
+	 * @var WP_Post the WP_Post that corresponds with this CPT model object
+	 */
+	protected $_wp_post;
+
+
+	abstract public function wp_user();
+
+
+	/**
+	 * Returns the WP post associated with this CPT model object. If this CPT is saved, fetches it
+	 * from the DB. Otherwise, create an unsaved WP_POst object. Caches the post internally.
+	 *
+	 * @return WP_Post
+	 */
+	public function wp_post()
+	{
+		global $wpdb;
+		if (! $this->_wp_post instanceof WP_Post) {
+			if ($this->ID()) {
+				$this->_wp_post = get_post($this->ID());
+			} else {
+				$simulated_db_result = new stdClass();
+				foreach ($this->get_model()->field_settings(true) as $field_name => $field_obj) {
+					if (
+						$this->get_model()->get_table_obj_by_alias($field_obj->get_table_alias())->get_table_name()
+						=== $wpdb->posts
+					) {
+						$column = $field_obj->get_table_column();
+
+						if ($field_obj instanceof EE_Datetime_Field) {
+							$value_on_model_obj = $this->get_DateTime_object($field_name);
+						} elseif ($field_obj->is_db_only_field()) {
+							$value_on_model_obj = $field_obj->get_default_value();
+						} else {
+							$value_on_model_obj = $this->get_raw($field_name);
+						}
+						$simulated_db_result->{$column} = $field_obj->prepare_for_use_in_db($value_on_model_obj);
+					}
+				}
+				$this->_wp_post = new WP_Post($simulated_db_result);
+			}
+			// and let's make retrieving the EE CPT object easy too
+			$classname = get_class($this);
+			if (! isset($this->_wp_post->{$classname})) {
+				$this->_wp_post->{$classname} = $this;
+			}
+		}
+		return $this->_wp_post;
+	}
+
+	/**
+	 * When fetching a new value for a post field that uses the global $post for rendering,
+	 * set the global $post temporarily to be this model object; and afterwards restore it
+	 *
+	 * @param string $fieldname
+	 * @param bool   $pretty
+	 * @param string $extra_cache_ref
+	 * @return mixed
+	 */
+	protected function _get_fresh_property($fieldname, $pretty = false, $extra_cache_ref = null)
+	{
+		global $post;
+
+		if (
+			$pretty
+			&& (
+				! (
+					$post instanceof WP_Post
+					&& $post->ID
+				)
+				|| (int) $post->ID !== $this->ID()
+			)
+			&& $this->get_model()->field_settings_for($fieldname) instanceof EE_Post_Content_Field
+		) {
+			$old_post = $post;
+			$post = $this->wp_post();
+			$return_value = parent::_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
+			$post = $old_post;
+		} else {
+			$return_value = parent::_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
+		}
+		return $return_value;
+	}
+
+	/**
+	 * Adds to the specified event category. If it category doesn't exist, creates it.
+	 *
+	 * @param string $category_name
+	 * @param string $category_description    optional
+	 * @param int    $parent_term_taxonomy_id optional
+	 * @return EE_Term_Taxonomy
+	 */
+	public function add_event_category($category_name, $category_description = null, $parent_term_taxonomy_id = null)
+	{
+		return $this->get_model()->add_event_category(
+			$this,
+			$category_name,
+			$category_description,
+			$parent_term_taxonomy_id
+		);
+	}
+
+
+	/**
+	 * Removes the event category by specified name from being related ot this event
+	 *
+	 * @param string $category_name
+	 * @return bool
+	 */
+	public function remove_event_category($category_name)
+	{
+		return $this->get_model()->remove_event_category($this, $category_name);
+	}
+
+
+	/**
+	 * Removes the relation to the specified term taxonomy, and maintains the
+	 * data integrity of the term taxonomy provided
+	 *
+	 * @param EE_Term_Taxonomy $term_taxonomy
+	 * @return EE_Base_Class the relation was removed from
+	 */
+	public function remove_relation_to_term_taxonomy($term_taxonomy)
+	{
+		if (! $term_taxonomy) {
+			EE_Error::add_error(
+				sprintf(
+					esc_html__(
+						"No Term_Taxonomy provided which to remove from model object of type %s and id %d",
+						"event_espresso"
+					),
+					get_class($this),
+					$this->ID()
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return null;
+		}
+		$term_taxonomy->set_count($term_taxonomy->count() - 1);
+		$term_taxonomy->save();
+		return $this->_remove_relation_to($term_taxonomy, 'Term_Taxonomy');
+	}
+
+
+	/**
+	 * The main purpose of this method is to return the post type for the model object
+	 *
+	 * @access public
+	 * @return string
+	 */
+	public function post_type()
+	{
+		return $this->get_model()->post_type();
+	}
+
+
+	/**
+	 * The main purpose of this method is to return the parent for the model object
+	 *
+	 * @access public
+	 * @return int
+	 */
+	public function parent()
+	{
+		return $this->get('parent');
+	}
+
+
+	/**
+	 * return the _status property
+	 *
+	 * @return string
+	 */
+	public function status()
+	{
+		return $this->get('status');
+	}
+
+
+	/**
+	 * @param string $status
+	 */
+	public function set_status($status)
+	{
+		$this->set('status', $status);
+	}
+
+
+	/**
+	 * This calls the equivalent model method for retrieving the feature image which in turn is a wrapper for
+	 * WordPress' get_the_post_thumbnail() function.
+	 *
+	 * @link   http://codex.wordpress.org/Function_Reference/get_the_post_thumbnail
+	 * @access protected
+	 * @param string|array $size (optional) Image size. Defaults to 'post-thumbnail' but can also be a 2-item array
+	 *                           representing width and height in pixels (i.e. array(32,32) ).
+	 * @param string|array $attr Optional. Query string or array of attributes.
+	 * @return string HTML image element
+	 */
+	protected function _get_feature_image($size, $attr)
+	{
+		// first let's see if we already have the _feature_image property set AND if it has a cached element on it FOR the given size
+		$attr_key = is_array($attr) ? implode('_', $attr) : $attr;
+		$cache_key = is_array($size) ? implode('_', $size) . $attr_key : $size . $attr_key;
+		$this->_feature_image[ $cache_key ] = isset($this->_feature_image[ $cache_key ])
+			? $this->_feature_image[ $cache_key ] : $this->get_model()->get_feature_image($this->ID(), $size, $attr);
+		return $this->_feature_image[ $cache_key ];
+	}
+
+
+	/**
+	 * See _get_feature_image. Returns the HTML to display a featured image
+	 *
+	 * @param string       $size
+	 * @param string|array $attr
+	 * @return string of html
+	 */
+	public function feature_image($size = 'thumbnail', $attr = '')
+	{
+		return $this->_get_feature_image($size, $attr);
+	}
+
+
+	/**
+	 * This uses the wp "wp_get_attachment_image_src()" function to return the feature image for the current class
+	 * using the given size params.
+	 *
+	 * @param  string|array $size can either be a string: 'thumbnail', 'medium', 'large', 'full' OR 2-item array
+	 *                            representing width and height in pixels eg. array(32,32).
+	 * @return string|boolean          the url of the image or false if not found
+	 */
+	public function feature_image_url($size = 'thumbnail')
+	{
+		$attachment = wp_get_attachment_image_src(get_post_thumbnail_id($this->ID()), $size);
+		return ! empty($attachment) ? $attachment[0] : false;
+	}
+
+
+	/**
+	 * This is a method for restoring this_obj using details from the given $revision_id
+	 *
+	 * @param int   $revision_id       ID of the revision we're getting data from
+	 * @param array $related_obj_names if included this will be used to restore for related obj
+	 *                                 if not included then we just do restore on the meta.
+	 *                                 We will accept an array of related_obj_names for restoration here.
+	 * @param array $where_query       You can optionally include an array of key=>value pairs
+	 *                                 that allow you to further constrict the relation to being added.
+	 *                                 However, keep in mind that the columns (keys) given
+	 *                                 must match a column on the JOIN table and currently
+	 *                                 only the HABTM models accept these additional conditions.
+	 *                                 Also remember that if an exact match isn't found for these extra cols/val pairs,
+	 *                                 then a NEW row is created in the join table.
+	 *                                 This array is INDEXED by RELATED OBJ NAME (so it corresponds with the obj_names
+	 *                                 sent);
+	 * @return void
+	 */
+	public function restore_revision($revision_id, $related_obj_names = array(), $where_query = array())
+	{
+		// get revision object
+		$revision_obj = $this->get_model()->get_one_by_ID($revision_id);
+		if ($revision_obj instanceof EE_CPT_Base) {
+			// no related_obj_name so we assume we're saving a revision on this object.
+			if (empty($related_obj_names)) {
+				$fields = $this->get_model()->get_meta_table_fields();
+				foreach ($fields as $field) {
+					$this->set($field, $revision_obj->get($field));
+				}
+				$this->save();
+			}
+			$related_obj_names = (array) $related_obj_names;
+			foreach ($related_obj_names as $related_name) {
+				// related_obj_name so we're saving a revision on an object related to this object
+				// do we have $where_query params for this related object?  If we do then we include that.
+				$cols_n_values = isset($where_query[ $related_name ]) ? $where_query[ $related_name ] : array();
+				$where_params = ! empty($cols_n_values) ? array($cols_n_values) : array();
+				$related_objs = $this->get_many_related($related_name, $where_params);
+				$revision_related_objs = $revision_obj->get_many_related($related_name, $where_params);
+				// load helper
+				// remove related objs from this object that are not in revision
+				// array_diff *should* work cause I think objects are indexed by ID?
+				$related_to_remove = EEH_Array::object_array_diff($related_objs, $revision_related_objs);
+				foreach ($related_to_remove as $rr) {
+					$this->_remove_relation_to($rr, $related_name, $cols_n_values);
+				}
+				// add all related objs attached to revision to this object
+				foreach ($revision_related_objs as $r_obj) {
+					$this->_add_relation_to($r_obj, $related_name, $cols_n_values);
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * Wrapper for get_post_meta, http://codex.wordpress.org/Function_Reference/get_post_meta
+	 *
+	 * @param string  $meta_key
+	 * @param boolean $single
+	 * @return mixed <ul><li>If only $id is set it will return all meta values in an associative array.</li>
+	 * <li>If $single is set to false, or left blank, the function returns an array containing all values of the
+	 * specified key.</li>
+	 * <li>If $single is set to true, the function returns the first value of the specified key (not in an
+	 * array</li></ul>
+	 */
+	public function get_post_meta($meta_key = null, $single = false)
+	{
+		return get_post_meta($this->ID(), $meta_key, $single);
+	}
+
+
+	/**
+	 * Wrapper for update_post_meta, http://codex.wordpress.org/Function_Reference/update_post_meta
+	 *
+	 * @param string $meta_key
+	 * @param mixed  $meta_value
+	 * @param mixed  $prev_value
+	 * @return mixed Returns meta_id if the meta doesn't exist, otherwise returns true on success and false on failure.
+	 *               NOTE: If the meta_value passed to this function is the same as the value that is already in the
+	 *               database, this function returns false.
+	 */
+	public function update_post_meta($meta_key, $meta_value, $prev_value = null)
+	{
+		if (! $this->ID()) {
+			$this->save();
+		}
+		return update_post_meta($this->ID(), $meta_key, $meta_value, $prev_value);
+	}
+
+
+	/**
+	 * Wrapper for add_post_meta, http://codex.wordpress.org/Function_Reference/add_post_meta
+	 *
+	 * @param mixed $meta_key
+	 * @param mixed $meta_value
+	 * @param bool  $unique . If postmeta for this $meta_key already exists, whether to add an additional item or not
+	 * @return boolean Boolean true, except if the $unique argument was set to true and a custom field with the given
+	 *                 key already exists, in which case false is returned.
+	 */
+	public function add_post_meta($meta_key, $meta_value, $unique = false)
+	{
+		if ($this->ID()) {
+			$this->save();
+		}
+		return add_post_meta($this->ID(), $meta_key, $meta_value, $unique);
+	}
+
+
+	/**
+	 * Wrapper for delete_post_meta, http://codex.wordpress.org/Function_Reference/delete_post_meta
+	 *
+	 * @param mixed $meta_key
+	 * @param mixed $meta_value
+	 * @return boolean False for failure. True for success.
+	 */
+	public function delete_post_meta($meta_key, $meta_value = '')
+	{
+		if (! $this->ID()) {
+			// there are obviously no postmetas for this if it's not saved
+			// so let's just report this as a success
+			return true;
+		}
+		return delete_post_meta($this->ID(), $meta_key, $meta_value);
+	}
+
+
+	/**
+	 * Gets the URL for viewing this event on the front-end
+	 *
+	 * @return string
+	 */
+	public function get_permalink()
+	{
+		return get_permalink($this->ID());
+	}
+
+
+	/**
+	 * Gets all the term-taxonomies for this CPT
+	 *
+	 * @param array $query_params
+	 * @return EE_Term_Taxonomy
+	 */
+	public function term_taxonomies($query_params = array())
+	{
+		return $this->get_many_related('Term_Taxonomy', $query_params);
+	}
+
+
+	/**
+	 * @return mixed
+	 */
+	public function get_custom_post_statuses()
+	{
+		return $this->get_model()->get_custom_post_statuses();
+	}
+
+
+	/**
+	 * @return mixed
+	 */
+	public function get_all_post_statuses()
+	{
+		return $this->get_model()->get_status_array();
+	}
+
+
+	/**
+	 * Don't serialize the WP Post. That's just duplicate data and we want to avoid recursion
+	 *
+	 * @return array
+	 */
+	public function __sleep()
+	{
+		$properties_to_serialize = parent::__sleep();
+		$properties_to_serialize = array_diff($properties_to_serialize, array('_wp_post'));
+		return $properties_to_serialize;
+	}
 }

caffeinated/core/domain/entities/routing/handlers/admin/PueRequests.php

Indentation +110 added lines, -110 removed lines

@@ -20,125 +20,125 @@
  */
 class PueRequests extends Route
 {
-    /**
-     * @var   bool
-     * @since $VID:$
-     */
-    private $load_pue = true;
+	/**
+	 * @var   bool
+	 * @since $VID:$
+	 */
+	private $load_pue = true;
 
 
-    /**
-     * returns true if the current request matches this route
-     *
-     * @return bool
-     * @since   $VID:$
-     */
-    public function matchesCurrentRequest(): bool
-    {
-        // route may match, but PUE loading is still conditional based on this filter
-        $this->load_pue = apply_filters('FHEE__EE_System__brew_espresso__load_pue', true);
-        return $this->request->isAdmin() || $this->request->isAdminAjax() || $this->request->isActivation();
-    }
+	/**
+	 * returns true if the current request matches this route
+	 *
+	 * @return bool
+	 * @since   $VID:$
+	 */
+	public function matchesCurrentRequest(): bool
+	{
+		// route may match, but PUE loading is still conditional based on this filter
+		$this->load_pue = apply_filters('FHEE__EE_System__brew_espresso__load_pue', true);
+		return $this->request->isAdmin() || $this->request->isAdminAjax() || $this->request->isActivation();
+	}
 
 
-    /**
-     * @since $VID:$
-     */
-    protected function registerDependencies()
-    {
-        if ($this->load_pue) {
-            $this->dependency_map->registerDependencies(
-                'EventEspresso\caffeinated\core\services\licensing\LicenseService',
-                [
-                    'EventEspresso\caffeinated\core\domain\services\pue\Stats'  => EE_Dependency_Map::load_from_cache,
-                    'EventEspresso\caffeinated\core\domain\services\pue\Config' => EE_Dependency_Map::load_from_cache,
-                ]
-            );
-            $this->dependency_map->registerDependencies(
-                'EventEspresso\caffeinated\core\domain\services\pue\Stats',
-                [
-                    'EventEspresso\caffeinated\core\domain\services\pue\Config'        => EE_Dependency_Map::load_from_cache,
-                    'EE_Maintenance_Mode'                                              => EE_Dependency_Map::load_from_cache,
-                    'EventEspresso\caffeinated\core\domain\services\pue\StatsGatherer' => EE_Dependency_Map::load_from_cache,
-                ]
-            );
-            $this->dependency_map->registerDependencies(
-                'EventEspresso\caffeinated\core\domain\services\pue\Config',
-                [
-                    'EE_Network_Config' => EE_Dependency_Map::load_from_cache,
-                    'EE_Config'         => EE_Dependency_Map::load_from_cache,
-                ]
-            );
-            $this->dependency_map->registerDependencies(
-                'EventEspresso\caffeinated\core\domain\services\pue\StatsGatherer',
-                [
-                    'EEM_Payment_Method' => EE_Dependency_Map::load_from_cache,
-                    'EEM_Event'          => EE_Dependency_Map::load_from_cache,
-                    'EEM_Datetime'       => EE_Dependency_Map::load_from_cache,
-                    'EEM_Ticket'         => EE_Dependency_Map::load_from_cache,
-                    'EEM_Registration'   => EE_Dependency_Map::load_from_cache,
-                    'EEM_Transaction'    => EE_Dependency_Map::load_from_cache,
-                    'EE_Config'          => EE_Dependency_Map::load_from_cache,
-                ]
-            );
-            $this->dependency_map->registerDependencies(
-                'EventEspresso\caffeinated\core\services\licensing\UserExperienceForm',
-                [
-                    'EE_Core_Config'         => EE_Dependency_Map::load_from_cache,
-                    'EE_Network_Core_Config' => EE_Dependency_Map::load_from_cache,
-                ]
-            );
-        }
-    }
+	/**
+	 * @since $VID:$
+	 */
+	protected function registerDependencies()
+	{
+		if ($this->load_pue) {
+			$this->dependency_map->registerDependencies(
+				'EventEspresso\caffeinated\core\services\licensing\LicenseService',
+				[
+					'EventEspresso\caffeinated\core\domain\services\pue\Stats'  => EE_Dependency_Map::load_from_cache,
+					'EventEspresso\caffeinated\core\domain\services\pue\Config' => EE_Dependency_Map::load_from_cache,
+				]
+			);
+			$this->dependency_map->registerDependencies(
+				'EventEspresso\caffeinated\core\domain\services\pue\Stats',
+				[
+					'EventEspresso\caffeinated\core\domain\services\pue\Config'        => EE_Dependency_Map::load_from_cache,
+					'EE_Maintenance_Mode'                                              => EE_Dependency_Map::load_from_cache,
+					'EventEspresso\caffeinated\core\domain\services\pue\StatsGatherer' => EE_Dependency_Map::load_from_cache,
+				]
+			);
+			$this->dependency_map->registerDependencies(
+				'EventEspresso\caffeinated\core\domain\services\pue\Config',
+				[
+					'EE_Network_Config' => EE_Dependency_Map::load_from_cache,
+					'EE_Config'         => EE_Dependency_Map::load_from_cache,
+				]
+			);
+			$this->dependency_map->registerDependencies(
+				'EventEspresso\caffeinated\core\domain\services\pue\StatsGatherer',
+				[
+					'EEM_Payment_Method' => EE_Dependency_Map::load_from_cache,
+					'EEM_Event'          => EE_Dependency_Map::load_from_cache,
+					'EEM_Datetime'       => EE_Dependency_Map::load_from_cache,
+					'EEM_Ticket'         => EE_Dependency_Map::load_from_cache,
+					'EEM_Registration'   => EE_Dependency_Map::load_from_cache,
+					'EEM_Transaction'    => EE_Dependency_Map::load_from_cache,
+					'EE_Config'          => EE_Dependency_Map::load_from_cache,
+				]
+			);
+			$this->dependency_map->registerDependencies(
+				'EventEspresso\caffeinated\core\services\licensing\UserExperienceForm',
+				[
+					'EE_Core_Config'         => EE_Dependency_Map::load_from_cache,
+					'EE_Network_Core_Config' => EE_Dependency_Map::load_from_cache,
+				]
+			);
+		}
+	}
 
 
-    /**
-     * implements logic required to run during request
-     *
-     * @return bool
-     * @since   $VID:$
-     */
-    protected function requestHandler(): bool
-    {
-        add_filter(
-            'FHEE__EE_Register_Addon__register',
-            [RegisterAddonPUE::class, 'registerPUE'],
-            10,
-            4
-        );
-        add_action(
-            'AHEE__EE_Register_Addon___load_and_init_addon_class',
-            [RegisterAddonPUE::class, 'setAddonPueSlug'],
-            10,
-            2
-        );
-        if ($this->load_pue) {
-            add_action('AHEE__EE_System__brew_espresso__complete', [$this, 'loadLicenseService']);
-            add_filter(
-                'FHEE__EventEspresso_admin_pages_general_settings_OrganizationSettings__generate__form',
-                [$this, 'loadUserExperienceForm']
-            );
-        }
+	/**
+	 * implements logic required to run during request
+	 *
+	 * @return bool
+	 * @since   $VID:$
+	 */
+	protected function requestHandler(): bool
+	{
+		add_filter(
+			'FHEE__EE_Register_Addon__register',
+			[RegisterAddonPUE::class, 'registerPUE'],
+			10,
+			4
+		);
+		add_action(
+			'AHEE__EE_Register_Addon___load_and_init_addon_class',
+			[RegisterAddonPUE::class, 'setAddonPueSlug'],
+			10,
+			2
+		);
+		if ($this->load_pue) {
+			add_action('AHEE__EE_System__brew_espresso__complete', [$this, 'loadLicenseService']);
+			add_filter(
+				'FHEE__EventEspresso_admin_pages_general_settings_OrganizationSettings__generate__form',
+				[$this, 'loadUserExperienceForm']
+			);
+		}
 
-        return true;
-    }
+		return true;
+	}
 
 
-    public function loadLicenseService()
-    {
-        /** @var LicenseService $license_service */
-        $license_service = $this->loader->getShared(LicenseService::class);
-        $license_service->loadPueClient();
-    }
+	public function loadLicenseService()
+	{
+		/** @var LicenseService $license_service */
+		$license_service = $this->loader->getShared(LicenseService::class);
+		$license_service->loadPueClient();
+	}
 
 
-    /**
-     * @throws EE_Error
-     */
-    public function loadUserExperienceForm(EE_Form_Section_Proper $org_settings_form): EE_Form_Section_Proper
-    {
-        /** @var UserExperienceForm $uxip_form */
-        $uxip_form = $this->loader->getShared(UserExperienceForm::class);
-        return $uxip_form->uxipFormSections($org_settings_form);
-    }
+	/**
+	 * @throws EE_Error
+	 */
+	public function loadUserExperienceForm(EE_Form_Section_Proper $org_settings_form): EE_Form_Section_Proper
+	{
+		/** @var UserExperienceForm $uxip_form */
+		$uxip_form = $this->loader->getShared(UserExperienceForm::class);
+		return $uxip_form->uxipFormSections($org_settings_form);
+	}
 }