eventespresso / event-espresso-core

core/db_classes/EE_Line_Item.class.php

Doc Comments +1 added lines, -1 removed lines

@@ -781,7 +781,7 @@
     /**
      * Gets the event that's related to the ticket, if this line item represents a ticket.
      *
-     * @return EE_Event|null
+     * @return EE_Base_Class|null
      * @throws EE_Error
      * @throws InvalidArgumentException
      * @throws InvalidDataTypeException

Spacing +15 added lines, -15 removed lines

@@ -88,7 +88,7 @@ 
     protected function __construct($fieldValues = array(), $bydb = false, $timezone = '')
     {
         parent::__construct($fieldValues, $bydb, $timezone);
-        if (! $this->get('LIN_code')) {
+        if ( ! $this->get('LIN_code')) {
             $this->set_code($this->generate_code());
         }
     }
@@ -155,7 +155,7 @@ 
     public function name()
     {
         $name = $this->get('LIN_name');
-        if (! $name) {
+        if ( ! $name) {
             $name = ucwords(str_replace('-', ' ', $this->type()));
         }
         return $name;
@@ -615,7 +615,7 @@ 
                 )
             );
         }
-        if (! is_array($this->_children)) {
+        if ( ! is_array($this->_children)) {
             $this->_children = array();
         }
         return $this->_children;
@@ -856,7 +856,7 @@ 
             }
             return $line_item->save();
         }
-        $this->_children[ $line_item->code() ] = $line_item;
+        $this->_children[$line_item->code()] = $line_item;
         if ($line_item->parent() !== $this) {
             $line_item->set_parent($this);
         }
@@ -880,7 +880,7 @@ 
     public function set_parent($line_item)
     {
         if ($this->ID()) {
-            if (! $line_item->ID()) {
+            if ( ! $line_item->ID()) {
                 $line_item->save();
             }
             $this->set_parent_ID($line_item->ID());
@@ -912,8 +912,8 @@ 
                 array(array('LIN_parent' => $this->ID(), 'LIN_code' => $code))
             );
         }
-        return isset($this->_children[ $code ])
-            ? $this->_children[ $code ]
+        return isset($this->_children[$code])
+            ? $this->_children[$code]
             : null;
     }
 
@@ -973,8 +973,8 @@ 
             }
             return $items_deleted;
         }
-        if (isset($this->_children[ $code ])) {
-            unset($this->_children[ $code ]);
+        if (isset($this->_children[$code])) {
+            unset($this->_children[$code]);
             return 1;
         }
         return 0;
@@ -1015,7 +1015,7 @@ 
     public function generate_code()
     {
         // each line item in the cart requires a unique identifier
-        return md5($this->get('OBJ_type') . $this->get('OBJ_ID') . microtime());
+        return md5($this->get('OBJ_type').$this->get('OBJ_ID').microtime());
     }
 
 
@@ -1220,7 +1220,7 @@ 
         $has_children = ! empty($my_children);
         if ($has_children && $this->is_line_item()) {
             $total = $this->_recalculate_pretax_total_for_line_item($total, $my_children);
-        } elseif (! $has_children && ($this->is_sub_line_item() || $this->is_line_item())) {
+        } elseif ( ! $has_children && ($this->is_sub_line_item() || $this->is_line_item())) {
             $total = $this->unit_price() * $this->quantity();
         } elseif ($this->is_sub_total() || $this->is_total()) {
             $total = $this->_recalculate_pretax_total_for_subtotal($total, $my_children);
@@ -1229,18 +1229,18 @@ 
             return 0;
         }
         // ensure all non-line items and non-sub-line-items have a quantity of 1 (except for Events)
-        if (! $this->is_line_item() && ! $this->is_sub_line_item() && ! $this->is_cancellation()
+        if ( ! $this->is_line_item() && ! $this->is_sub_line_item() && ! $this->is_cancellation()
         ) {
             if ($this->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_EVENT) {
                 $this->set_quantity(1);
             }
-            if (! $this->is_percent()) {
+            if ( ! $this->is_percent()) {
                 $this->set_unit_price($total);
             }
         }
         // we don't want to bother saving grand totals, because that needs to factor in taxes anyways
         // so it ought to be
-        if (! $this->is_total()) {
+        if ( ! $this->is_total()) {
             $this->set_total($total);
             // if not a percent line item, make sure we keep the unit price in sync
             if ($has_children
@@ -1587,7 +1587,7 @@ 
     public function save_this_and_descendants_to_txn($txn_id = null)
     {
         $count = 0;
-        if (! $txn_id) {
+        if ( ! $txn_id) {
             $txn_id = $this->TXN_ID();
         }
         $this->set_TXN_ID($txn_id);

Indentation +1735 added lines, -1735 removed lines

@@ -14,1739 +14,1739 @@
 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;
-
-
-    /**
-     * @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, $timezone = '')
-    {
-        parent::__construct($fieldValues, $bydb, $timezone);
-        if (! $this->get('LIN_code')) {
-            $this->set_code($this->generate_code());
-        }
-    }
-
-
-    /**
-     * 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()
-    {
-        return $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 string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function OBJ_ID()
-    {
-        return $this->get('OBJ_ID');
-    }
-
-
-    /**
-     * Sets item_id
-     *
-     * @param string $item_id
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_OBJ_ID($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');
-    }
-
-
-    /**
-     * 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 total()
-    {
-        return $this->get('LIN_total');
-    }
-
-
-    /**
-     * Sets total
-     *
-     * @param float $total
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_total($total)
-    {
-        $this->set('LIN_total', $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())
-            : $this->_parent;
-    }
-
-
-    /**
-     * Gets ALL the children of this line item (ie, all the parts that contribute towards this total).
-     *
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function children()
-    {
-        if ($this->ID()) {
-            return $this->get_model()->get_all(
-                array(
-                    array('LIN_parent' => $this->ID()),
-                    'order_by' => array('LIN_order' => 'ASC'),
-                )
-            );
-        }
-        if (! is_array($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);
-    }
-
-
-    /**
-     * 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 EEI_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(EEI_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 is_tax()
-    {
-        return $this->type() === EEM_Line_Item::type_tax;
-    }
-
-
-    /**
-     * @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 InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function unit_price_no_code()
-    {
-        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 InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function total_no_code()
-    {
-        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 $update_txn_status
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    public function recalculate_total_including_taxes($update_txn_status = false)
-    {
-        $pre_tax_total = $this->recalculate_pre_tax_total();
-        $tax_total = $this->recalculate_taxes_and_tax_total();
-        $total = $pre_tax_total + $tax_total;
-        // no negative totals plz
-        $total = max($total, 0);
-        $this->set_total($total);
-        // only update the related transaction's total
-        // if we intend to save this line item and its a grand total
-        if ($this->allow_persist() && $this->type() === EEM_Line_Item::type_total
-            && $this->transaction()
-               instanceof
-               EE_Transaction
-        ) {
-            $this->transaction()->set_total($total);
-            if ($update_txn_status) {
-                // don't save the TXN because that will be done below
-                // and the following method only saves if the status changes
-                $this->transaction()->update_status_based_on_total_paid(false);
-            }
-            if ($this->transaction()->ID()) {
-                $this->transaction()->save();
-            }
-        }
-        $this->maybe_save();
-        return $total;
-    }
-
-
-    /**
-     * 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()
-    {
-        $total = 0;
-        $my_children = $this->children();
-        $has_children = ! empty($my_children);
-        if ($has_children && $this->is_line_item()) {
-            $total = $this->_recalculate_pretax_total_for_line_item($total, $my_children);
-        } elseif (! $has_children && ($this->is_sub_line_item() || $this->is_line_item())) {
-            $total = $this->unit_price() * $this->quantity();
-        } elseif ($this->is_sub_total() || $this->is_total()) {
-            $total = $this->_recalculate_pretax_total_for_subtotal($total, $my_children);
-        } elseif ($this->is_tax_sub_total() || $this->is_tax() || $this->is_cancelled()) {
-            // completely ignore tax totals, tax sub-totals, and cancelled line items, when calculating the pre-tax-total
-            return 0;
-        }
-        // ensure all non-line items and non-sub-line-items have a quantity of 1 (except for Events)
-        if (! $this->is_line_item() && ! $this->is_sub_line_item() && ! $this->is_cancellation()
-        ) {
-            if ($this->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_EVENT) {
-                $this->set_quantity(1);
-            }
-            if (! $this->is_percent()) {
-                $this->set_unit_price($total);
-            }
-        }
-        // we don't want to bother saving grand totals, because that needs to factor in taxes anyways
-        // so it ought to be
-        if (! $this->is_total()) {
-            $this->set_total($total);
-            // if not a percent line item, make sure we keep the unit price in sync
-            if ($has_children
-                && $this->is_line_item()
-                && ! $this->is_percent()
-            ) {
-                if ($this->quantity() === 0) {
-                    $new_unit_price = 0;
-                } else {
-                    $new_unit_price = $this->total() / $this->quantity();
-                }
-                $this->set_unit_price($new_unit_price);
-            }
-            $this->maybe_save();
-        }
-        return $total;
-    }
-
-
-    /**
-     * Calculates the pretax total when this line item is a subtotal or total line item.
-     * Basically does a sum-then-round approach (ie, any percent line item that are children
-     * will calculate their total based on the un-rounded total we're working with so far, and
-     * THEN round the result; instead of rounding as we go like with sub-line-items)
-     *
-     * @param float          $calculated_total_so_far
-     * @param EE_Line_Item[] $my_children
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _recalculate_pretax_total_for_subtotal($calculated_total_so_far, $my_children = null)
-    {
-        if ($my_children === null) {
-            $my_children = $this->children();
-        }
-        $subtotal_quantity = 0;
-        // get the total of all its children
-        foreach ($my_children as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item && ! $child_line_item->is_cancellation()) {
-                // percentage line items are based on total so far
-                if ($child_line_item->is_percent()) {
-                    // round as we go so that the line items add up ok
-                    $percent_total = round(
-                        $calculated_total_so_far * $child_line_item->percent() / 100,
-                        EE_Registry::instance()->CFG->currency->dec_plc
-                    );
-                    $child_line_item->set_total($percent_total);
-                    // so far all percent line items should have a quantity of 1
-                    // (ie, no double percent discounts. Although that might be requested someday)
-                    $child_line_item->set_quantity(1);
-                    $child_line_item->maybe_save();
-                    $calculated_total_so_far += $percent_total;
-                } else {
-                    // verify flat sub-line-item quantities match their parent
-                    if ($child_line_item->is_sub_line_item()) {
-                        $child_line_item->set_quantity($this->quantity());
-                    }
-                    $calculated_total_so_far += $child_line_item->recalculate_pre_tax_total();
-                    $subtotal_quantity += $child_line_item->quantity();
-                }
-            }
-        }
-        if ($this->is_sub_total()) {
-            // no negative totals plz
-            $calculated_total_so_far = max($calculated_total_so_far, 0);
-            $subtotal_quantity = $subtotal_quantity > 0 ? 1 : 0;
-            $this->set_quantity($subtotal_quantity);
-            $this->maybe_save();
-        }
-        return $calculated_total_so_far;
-    }
-
-
-    /**
-     * Calculates the pretax total for a normal line item, in a round-then-sum approach
-     * (where each sub-line-item is applied to the base price for the line item
-     * and the result is immediately rounded, rather than summing all the sub-line-items
-     * then rounding, like we do when recalculating pretax totals on totals and subtotals).
-     *
-     * @param float          $calculated_total_so_far
-     * @param EE_Line_Item[] $my_children
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _recalculate_pretax_total_for_line_item($calculated_total_so_far, $my_children = null)
-    {
-        if ($my_children === null) {
-            $my_children = $this->children();
-        }
-        // we need to keep track of the running total for a single item,
-        // because we need to round as we go
-        $unit_price_for_total = 0;
-        $quantity_for_total = 1;
-        // get the total of all its children
-        foreach ($my_children as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item && ! $child_line_item->is_cancellation()) {
-                if ($child_line_item->is_percent()) {
-                    // it should be the unit-price-so-far multiplied by teh percent multiplied by the quantity
-                    // not total multiplied by percent, because that ignores rounding along-the-way
-                    $percent_unit_price = round(
-                        $unit_price_for_total * $child_line_item->percent() / 100,
-                        EE_Registry::instance()->CFG->currency->dec_plc
-                    );
-                    $percent_total = $percent_unit_price * $quantity_for_total;
-                    $child_line_item->set_total($percent_total);
-                    // so far all percent line items should have a quantity of 1
-                    // (ie, no double percent discounts. Although that might be requested someday)
-                    $child_line_item->set_quantity(1);
-                    $child_line_item->maybe_save();
-                    $calculated_total_so_far += $percent_total;
-                    $unit_price_for_total += $percent_unit_price;
-                } else {
-                    // verify flat sub-line-item quantities match their parent
-                    if ($child_line_item->is_sub_line_item()) {
-                        $child_line_item->set_quantity($this->quantity());
-                    }
-                    $quantity_for_total = $child_line_item->quantity();
-                    $calculated_total_so_far += $child_line_item->recalculate_pre_tax_total();
-                    $unit_price_for_total += $child_line_item->unit_price();
-                }
-            }
-        }
-        return $calculated_total_so_far;
-    }
-
-
-    /**
-     * 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()
-    {
-        // get all taxes
-        $taxes = $this->tax_descendants();
-        // calculate the pretax total
-        $taxable_total = $this->taxable_total();
-        $tax_total = 0;
-        foreach ($taxes as $tax) {
-            $total_on_this_tax = $taxable_total * $tax->percent() / 100;
-            // remember the total on this line item
-            $tax->set_total($total_on_this_tax);
-            $tax->maybe_save();
-            $tax_total += $tax->total();
-        }
-        $this->_recalculate_tax_sub_total();
-        return $tax_total;
-    }
-
-
-    /**
-     * Simply forces all the tax-sub-totals to recalculate. Assumes the taxes have been calculated
-     *
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    private function _recalculate_tax_sub_total()
-    {
-        if ($this->is_tax_sub_total()) {
-            $total = 0;
-            $total_percent = 0;
-            // simply loop through all its children (which should be taxes) and sum their total
-            foreach ($this->children() as $child_tax) {
-                if ($child_tax instanceof EE_Line_Item) {
-                    $total += $child_tax->total();
-                    $total_percent += $child_tax->percent();
-                }
-            }
-            $this->set_total($total);
-            $this->set_percent($total_percent);
-            $this->maybe_save();
-        } elseif ($this->is_total()) {
-            foreach ($this->children() as $maybe_tax_subtotal) {
-                if ($maybe_tax_subtotal instanceof EE_Line_Item) {
-                    $maybe_tax_subtotal->_recalculate_tax_sub_total();
-                }
-            }
-        }
-    }
-
-
-    /**
-     * 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()
-    {
-        $this->_recalculate_tax_sub_total();
-        $total = 0;
-        foreach ($this->tax_descendants() as $tax_line_item) {
-            if ($tax_line_item instanceof EE_Line_Item) {
-                $total += $tax_line_item->total();
-            }
-        }
-        return $total;
-    }
-
-
-    /**
-     * Gets the total for all the items purchased only
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_items_total()
-    {
-        // by default, let's make sure we're consistent with the existing line item
-        if ($this->is_total()) {
-            $pretax_subtotal_li = EEH_Line_Item::get_pre_tax_subtotal($this);
-            if ($pretax_subtotal_li instanceof EE_Line_Item) {
-                return $pretax_subtotal_li->total();
-            }
-        }
-        $total = 0;
-        foreach ($this->get_items() as $item) {
-            if ($item instanceof EE_Line_Item) {
-                $total += $item->total();
-            }
-        }
-        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()
-    {
-        $total = 0;
-        if ($this->children()) {
-            foreach ($this->children() as $child_line_item) {
-                if ($child_line_item->type() === EEM_Line_Item::type_line_item && $child_line_item->is_taxable()) {
-                    // if it's a percent item, only take into account the percent
-                    // that's taxable too (the taxable total so far)
-                    if ($child_line_item->is_percent()) {
-                        $total += ($total * $child_line_item->percent() / 100);
-                    } else {
-                        $total += $child_line_item->total();
-                    }
-                } elseif ($child_line_item->type() === EEM_Line_Item::type_sub_total) {
-                    $total += $child_line_item->taxable_total();
-                }
-            }
-        }
-        return max($total, 0);
-    }
-
-
-    /**
-     * 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 $count;
-    }
-
-
-    /**
-     * returns the cancellation line item if this item was cancelled
-     *
-     * @return EE_Line_Item[]
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws ReflectionException
-     * @throws EE_Error
-     */
-    public function get_cancellations()
-    {
-        EE_Registry::instance()->load_helper('Line_Item');
-        return EEH_Line_Item::get_descendants_of_type($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 $type like one of the EEM_Line_Item::type_*
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_nearest_descendant_of_type($type)
-    {
-        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;
+
+
+	/**
+	 * @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, $timezone = '')
+	{
+		parent::__construct($fieldValues, $bydb, $timezone);
+		if (! $this->get('LIN_code')) {
+			$this->set_code($this->generate_code());
+		}
+	}
+
+
+	/**
+	 * 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()
+	{
+		return $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 string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function OBJ_ID()
+	{
+		return $this->get('OBJ_ID');
+	}
+
+
+	/**
+	 * Sets item_id
+	 *
+	 * @param string $item_id
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_OBJ_ID($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');
+	}
+
+
+	/**
+	 * 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 total()
+	{
+		return $this->get('LIN_total');
+	}
+
+
+	/**
+	 * Sets total
+	 *
+	 * @param float $total
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_total($total)
+	{
+		$this->set('LIN_total', $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())
+			: $this->_parent;
+	}
+
+
+	/**
+	 * Gets ALL the children of this line item (ie, all the parts that contribute towards this total).
+	 *
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function children()
+	{
+		if ($this->ID()) {
+			return $this->get_model()->get_all(
+				array(
+					array('LIN_parent' => $this->ID()),
+					'order_by' => array('LIN_order' => 'ASC'),
+				)
+			);
+		}
+		if (! is_array($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);
+	}
+
+
+	/**
+	 * 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 EEI_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(EEI_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 is_tax()
+	{
+		return $this->type() === EEM_Line_Item::type_tax;
+	}
+
+
+	/**
+	 * @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 InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function unit_price_no_code()
+	{
+		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 InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function total_no_code()
+	{
+		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 $update_txn_status
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	public function recalculate_total_including_taxes($update_txn_status = false)
+	{
+		$pre_tax_total = $this->recalculate_pre_tax_total();
+		$tax_total = $this->recalculate_taxes_and_tax_total();
+		$total = $pre_tax_total + $tax_total;
+		// no negative totals plz
+		$total = max($total, 0);
+		$this->set_total($total);
+		// only update the related transaction's total
+		// if we intend to save this line item and its a grand total
+		if ($this->allow_persist() && $this->type() === EEM_Line_Item::type_total
+			&& $this->transaction()
+			   instanceof
+			   EE_Transaction
+		) {
+			$this->transaction()->set_total($total);
+			if ($update_txn_status) {
+				// don't save the TXN because that will be done below
+				// and the following method only saves if the status changes
+				$this->transaction()->update_status_based_on_total_paid(false);
+			}
+			if ($this->transaction()->ID()) {
+				$this->transaction()->save();
+			}
+		}
+		$this->maybe_save();
+		return $total;
+	}
+
+
+	/**
+	 * 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()
+	{
+		$total = 0;
+		$my_children = $this->children();
+		$has_children = ! empty($my_children);
+		if ($has_children && $this->is_line_item()) {
+			$total = $this->_recalculate_pretax_total_for_line_item($total, $my_children);
+		} elseif (! $has_children && ($this->is_sub_line_item() || $this->is_line_item())) {
+			$total = $this->unit_price() * $this->quantity();
+		} elseif ($this->is_sub_total() || $this->is_total()) {
+			$total = $this->_recalculate_pretax_total_for_subtotal($total, $my_children);
+		} elseif ($this->is_tax_sub_total() || $this->is_tax() || $this->is_cancelled()) {
+			// completely ignore tax totals, tax sub-totals, and cancelled line items, when calculating the pre-tax-total
+			return 0;
+		}
+		// ensure all non-line items and non-sub-line-items have a quantity of 1 (except for Events)
+		if (! $this->is_line_item() && ! $this->is_sub_line_item() && ! $this->is_cancellation()
+		) {
+			if ($this->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_EVENT) {
+				$this->set_quantity(1);
+			}
+			if (! $this->is_percent()) {
+				$this->set_unit_price($total);
+			}
+		}
+		// we don't want to bother saving grand totals, because that needs to factor in taxes anyways
+		// so it ought to be
+		if (! $this->is_total()) {
+			$this->set_total($total);
+			// if not a percent line item, make sure we keep the unit price in sync
+			if ($has_children
+				&& $this->is_line_item()
+				&& ! $this->is_percent()
+			) {
+				if ($this->quantity() === 0) {
+					$new_unit_price = 0;
+				} else {
+					$new_unit_price = $this->total() / $this->quantity();
+				}
+				$this->set_unit_price($new_unit_price);
+			}
+			$this->maybe_save();
+		}
+		return $total;
+	}
+
+
+	/**
+	 * Calculates the pretax total when this line item is a subtotal or total line item.
+	 * Basically does a sum-then-round approach (ie, any percent line item that are children
+	 * will calculate their total based on the un-rounded total we're working with so far, and
+	 * THEN round the result; instead of rounding as we go like with sub-line-items)
+	 *
+	 * @param float          $calculated_total_so_far
+	 * @param EE_Line_Item[] $my_children
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _recalculate_pretax_total_for_subtotal($calculated_total_so_far, $my_children = null)
+	{
+		if ($my_children === null) {
+			$my_children = $this->children();
+		}
+		$subtotal_quantity = 0;
+		// get the total of all its children
+		foreach ($my_children as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item && ! $child_line_item->is_cancellation()) {
+				// percentage line items are based on total so far
+				if ($child_line_item->is_percent()) {
+					// round as we go so that the line items add up ok
+					$percent_total = round(
+						$calculated_total_so_far * $child_line_item->percent() / 100,
+						EE_Registry::instance()->CFG->currency->dec_plc
+					);
+					$child_line_item->set_total($percent_total);
+					// so far all percent line items should have a quantity of 1
+					// (ie, no double percent discounts. Although that might be requested someday)
+					$child_line_item->set_quantity(1);
+					$child_line_item->maybe_save();
+					$calculated_total_so_far += $percent_total;
+				} else {
+					// verify flat sub-line-item quantities match their parent
+					if ($child_line_item->is_sub_line_item()) {
+						$child_line_item->set_quantity($this->quantity());
+					}
+					$calculated_total_so_far += $child_line_item->recalculate_pre_tax_total();
+					$subtotal_quantity += $child_line_item->quantity();
+				}
+			}
+		}
+		if ($this->is_sub_total()) {
+			// no negative totals plz
+			$calculated_total_so_far = max($calculated_total_so_far, 0);
+			$subtotal_quantity = $subtotal_quantity > 0 ? 1 : 0;
+			$this->set_quantity($subtotal_quantity);
+			$this->maybe_save();
+		}
+		return $calculated_total_so_far;
+	}
+
+
+	/**
+	 * Calculates the pretax total for a normal line item, in a round-then-sum approach
+	 * (where each sub-line-item is applied to the base price for the line item
+	 * and the result is immediately rounded, rather than summing all the sub-line-items
+	 * then rounding, like we do when recalculating pretax totals on totals and subtotals).
+	 *
+	 * @param float          $calculated_total_so_far
+	 * @param EE_Line_Item[] $my_children
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _recalculate_pretax_total_for_line_item($calculated_total_so_far, $my_children = null)
+	{
+		if ($my_children === null) {
+			$my_children = $this->children();
+		}
+		// we need to keep track of the running total for a single item,
+		// because we need to round as we go
+		$unit_price_for_total = 0;
+		$quantity_for_total = 1;
+		// get the total of all its children
+		foreach ($my_children as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item && ! $child_line_item->is_cancellation()) {
+				if ($child_line_item->is_percent()) {
+					// it should be the unit-price-so-far multiplied by teh percent multiplied by the quantity
+					// not total multiplied by percent, because that ignores rounding along-the-way
+					$percent_unit_price = round(
+						$unit_price_for_total * $child_line_item->percent() / 100,
+						EE_Registry::instance()->CFG->currency->dec_plc
+					);
+					$percent_total = $percent_unit_price * $quantity_for_total;
+					$child_line_item->set_total($percent_total);
+					// so far all percent line items should have a quantity of 1
+					// (ie, no double percent discounts. Although that might be requested someday)
+					$child_line_item->set_quantity(1);
+					$child_line_item->maybe_save();
+					$calculated_total_so_far += $percent_total;
+					$unit_price_for_total += $percent_unit_price;
+				} else {
+					// verify flat sub-line-item quantities match their parent
+					if ($child_line_item->is_sub_line_item()) {
+						$child_line_item->set_quantity($this->quantity());
+					}
+					$quantity_for_total = $child_line_item->quantity();
+					$calculated_total_so_far += $child_line_item->recalculate_pre_tax_total();
+					$unit_price_for_total += $child_line_item->unit_price();
+				}
+			}
+		}
+		return $calculated_total_so_far;
+	}
+
+
+	/**
+	 * 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()
+	{
+		// get all taxes
+		$taxes = $this->tax_descendants();
+		// calculate the pretax total
+		$taxable_total = $this->taxable_total();
+		$tax_total = 0;
+		foreach ($taxes as $tax) {
+			$total_on_this_tax = $taxable_total * $tax->percent() / 100;
+			// remember the total on this line item
+			$tax->set_total($total_on_this_tax);
+			$tax->maybe_save();
+			$tax_total += $tax->total();
+		}
+		$this->_recalculate_tax_sub_total();
+		return $tax_total;
+	}
+
+
+	/**
+	 * Simply forces all the tax-sub-totals to recalculate. Assumes the taxes have been calculated
+	 *
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	private function _recalculate_tax_sub_total()
+	{
+		if ($this->is_tax_sub_total()) {
+			$total = 0;
+			$total_percent = 0;
+			// simply loop through all its children (which should be taxes) and sum their total
+			foreach ($this->children() as $child_tax) {
+				if ($child_tax instanceof EE_Line_Item) {
+					$total += $child_tax->total();
+					$total_percent += $child_tax->percent();
+				}
+			}
+			$this->set_total($total);
+			$this->set_percent($total_percent);
+			$this->maybe_save();
+		} elseif ($this->is_total()) {
+			foreach ($this->children() as $maybe_tax_subtotal) {
+				if ($maybe_tax_subtotal instanceof EE_Line_Item) {
+					$maybe_tax_subtotal->_recalculate_tax_sub_total();
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * 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()
+	{
+		$this->_recalculate_tax_sub_total();
+		$total = 0;
+		foreach ($this->tax_descendants() as $tax_line_item) {
+			if ($tax_line_item instanceof EE_Line_Item) {
+				$total += $tax_line_item->total();
+			}
+		}
+		return $total;
+	}
+
+
+	/**
+	 * Gets the total for all the items purchased only
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_items_total()
+	{
+		// by default, let's make sure we're consistent with the existing line item
+		if ($this->is_total()) {
+			$pretax_subtotal_li = EEH_Line_Item::get_pre_tax_subtotal($this);
+			if ($pretax_subtotal_li instanceof EE_Line_Item) {
+				return $pretax_subtotal_li->total();
+			}
+		}
+		$total = 0;
+		foreach ($this->get_items() as $item) {
+			if ($item instanceof EE_Line_Item) {
+				$total += $item->total();
+			}
+		}
+		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()
+	{
+		$total = 0;
+		if ($this->children()) {
+			foreach ($this->children() as $child_line_item) {
+				if ($child_line_item->type() === EEM_Line_Item::type_line_item && $child_line_item->is_taxable()) {
+					// if it's a percent item, only take into account the percent
+					// that's taxable too (the taxable total so far)
+					if ($child_line_item->is_percent()) {
+						$total += ($total * $child_line_item->percent() / 100);
+					} else {
+						$total += $child_line_item->total();
+					}
+				} elseif ($child_line_item->type() === EEM_Line_Item::type_sub_total) {
+					$total += $child_line_item->taxable_total();
+				}
+			}
+		}
+		return max($total, 0);
+	}
+
+
+	/**
+	 * 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 $count;
+	}
+
+
+	/**
+	 * returns the cancellation line item if this item was cancelled
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws ReflectionException
+	 * @throws EE_Error
+	 */
+	public function get_cancellations()
+	{
+		EE_Registry::instance()->load_helper('Line_Item');
+		return EEH_Line_Item::get_descendants_of_type($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 $type like one of the EEM_Line_Item::type_*
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_nearest_descendant_of_type($type)
+	{
+		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

Doc Comments +2 added lines, -1 removed lines

@@ -1027,7 +1027,7 @@ 
      * Deletes ALL children of the passed line item
      *
      * @param EE_Line_Item $parent_line_item
-     * @return bool
+     * @return integer
      * @throws EE_Error
      * @throws InvalidArgumentException
      * @throws InvalidDataTypeException
@@ -1333,6 +1333,7 @@ 
      * @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
+     * @param string $obj_type
      * @return EE_Line_Item[]
      * @throws EE_Error
      */

Spacing +36 added lines, -36 removed lines

@@ -138,7 +138,7 @@ 
      */
     public static function add_ticket_purchase(EE_Line_Item $total_line_item, EE_Ticket $ticket, $qty = 1)
     {
-        if (! $total_line_item instanceof EE_Line_Item || ! $total_line_item->is_total()) {
+        if ( ! $total_line_item instanceof EE_Line_Item || ! $total_line_item->is_total()) {
             throw new EE_Error(
                 sprintf(
                     esc_html__(
@@ -153,7 +153,7 @@ 
         // 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) {
+        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();
@@ -214,7 +214,7 @@ 
      */
     public static function increment_quantity(EE_Line_Item $line_item, $qty = 1)
     {
-        if (! $line_item->is_percent()) {
+        if ( ! $line_item->is_percent()) {
             $qty += $line_item->quantity();
             $line_item->set_quantity($qty);
             $line_item->set_total($line_item->unit_price() * $qty);
@@ -243,7 +243,7 @@ 
      */
     public static function decrement_quantity(EE_Line_Item $line_item, $qty = 1)
     {
-        if (! $line_item->is_percent()) {
+        if ( ! $line_item->is_percent()) {
             $qty = $line_item->quantity() - $qty;
             $qty = max($qty, 0);
             $line_item->set_quantity($qty);
@@ -272,7 +272,7 @@ 
      */
     public static function update_quantity(EE_Line_Item $line_item, $new_quantity)
     {
-        if (! $line_item->is_percent()) {
+        if ( ! $line_item->is_percent()) {
             $line_item->set_quantity($new_quantity);
             $line_item->set_total($line_item->unit_price() * $new_quantity);
             $line_item->save();
@@ -312,7 +312,7 @@ 
         // 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_desc'       => $ticket->description() !== '' ? $ticket->description().' '.$event : $event,
             'LIN_unit_price' => $ticket->price(),
             'LIN_quantity'   => $qty,
             'LIN_is_taxable' => $ticket->taxable(),
@@ -462,7 +462,7 @@ 
                         'event_espresso'
                     ),
                     $ticket_line_item->name(),
-                    current_time(get_option('date_format') . ' ' . get_option('time_format'))
+                    current_time(get_option('date_format').' '.get_option('time_format'))
                 ),
                 'LIN_unit_price' => 0, // $ticket_line_item->unit_price()
                 'LIN_quantity'   => $qty,
@@ -524,7 +524,7 @@ 
         );
         $cancellation_line_item = reset($cancellation_line_item);
         // verify that this ticket was indeed previously cancelled
-        if (! $cancellation_line_item instanceof EE_Line_Item) {
+        if ( ! $cancellation_line_item instanceof EE_Line_Item) {
             return false;
         }
         if ($cancellation_line_item->quantity() > $qty) {
@@ -729,7 +729,7 @@ 
             '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
+            'LIN_order' => 1000, // this should always come last
         ));
         $tax_line_item = apply_filters(
             'FHEE__EEH_Line_Item__create_taxes_subtotal__tax_line_item',
@@ -785,7 +785,7 @@ 
      */
     public static function get_event_code($event)
     {
-        return 'event-' . ($event instanceof EE_Event ? $event->ID() : '0');
+        return 'event-'.($event instanceof EE_Event ? $event->ID() : '0');
     }
 
 
@@ -834,7 +834,7 @@ 
     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) {
+        if ( ! $first_datetime instanceof EE_Datetime) {
             throw new EE_Error(
                 sprintf(
                     __('The supplied ticket (ID %d) has no datetimes', 'event_espresso'),
@@ -843,7 +843,7 @@ 
             );
         }
         $event = $first_datetime->event();
-        if (! $event instanceof EE_Event) {
+        if ( ! $event instanceof EE_Event) {
             throw new EE_Error(
                 sprintf(
                     esc_html__(
@@ -855,7 +855,7 @@ 
             );
         }
         $events_sub_total = EEH_Line_Item::get_event_line_item($grand_total, $event);
-        if (! $events_sub_total instanceof EE_Line_Item) {
+        if ( ! $events_sub_total instanceof EE_Line_Item) {
             throw new EE_Error(
                 sprintf(
                     esc_html__(
@@ -891,7 +891,7 @@ 
         $found = false;
         foreach (EEH_Line_Item::get_event_subtotals($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()) {
+            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;
@@ -903,7 +903,7 @@ 
                 break;
             }
         }
-        if (! $found) {
+        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
@@ -1018,7 +1018,7 @@ 
     public static function ensure_taxes_applied($total_line_item)
     {
         $taxes_subtotal = self::get_taxes_subtotal($total_line_item);
-        if (! $taxes_subtotal->children()) {
+        if ( ! $taxes_subtotal->children()) {
             self::apply_taxes($total_line_item);
         }
         return $taxes_subtotal->total();
@@ -1085,7 +1085,7 @@ 
         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)) {
+        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);
         }
@@ -1192,7 +1192,7 @@ 
         if ($code_substring_for_whitelist !== null) {
             $whitelisted = strpos($line_item->code(), $code_substring_for_whitelist) !== false;
         }
-        if (! $whitelisted && $line_item->is_line_item()) {
+        if ( ! $whitelisted && $line_item->is_line_item()) {
             $line_item->set_is_taxable($taxable);
         }
         foreach ($line_item->children() as $child_line_item) {
@@ -1554,7 +1554,7 @@ 
     public static function visualize(EE_Line_Item $line_item, $indentation = 0)
     {
         echo defined('EE_TESTS_DIR') ? "\n" : '<br />';
-        if (! $indentation) {
+        if ( ! $indentation) {
             echo defined('EE_TESTS_DIR') ? "\n" : '<br />';
         }
         for ($i = 0; $i < $indentation; $i++) {
@@ -1565,12 +1565,12 @@ 
             if ($line_item->is_percent()) {
                 $breakdown = "{$line_item->percent()}%";
             } else {
-                $breakdown = '$' . "{$line_item->unit_price()} x {$line_item->quantity()}";
+                $breakdown = '$'."{$line_item->unit_price()} x {$line_item->quantity()}";
             }
         }
         echo $line_item->name();
         echo " [ ID:{$line_item->ID()} | qty:{$line_item->quantity()} ] {$line_item->type()} : ";
-        echo '$' . (string) $line_item->total();
+        echo '$'.(string) $line_item->total();
         if ($breakdown) {
             echo " ( {$breakdown} )";
         }
@@ -1658,8 +1658,8 @@ 
                         if ($line_item_id === 'taxable') {
                             continue;
                         }
-                        $taxable_total = $running_totals['taxable'][ $line_item_id ];
-                        $running_totals[ $line_item_id ] += ($taxable_total * $tax_percent_decimal);
+                        $taxable_total = $running_totals['taxable'][$line_item_id];
+                        $running_totals[$line_item_id] += ($taxable_total * $tax_percent_decimal);
                     }
                     break;
 
@@ -1667,7 +1667,7 @@ 
                     // 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[ $child_line_item->ID() ])) {
+                        if (isset($running_totals[$child_line_item->ID()])) {
                             // huh? that shouldn't happen.
                             $running_totals['total'] += $child_line_item->total();
                         } else {
@@ -1678,18 +1678,18 @@ 
                                 $taxable_amount = 0;
                             }
                             // are we only calculating totals for some tickets?
-                            if (isset($billable_ticket_quantities[ $child_line_item->OBJ_ID() ])) {
-                                $quantity = $billable_ticket_quantities[ $child_line_item->OBJ_ID() ];
-                                $running_totals[ $child_line_item->ID() ] = $quantity
+                            if (isset($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
+                                $running_totals['taxable'][$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;
+                                $running_totals[$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;
@@ -1709,12 +1709,12 @@ 
                             }
                             // update the running totals
                             // yes this actually even works for the running grand total!
-                            $running_totals[ $line_item_id ] =
+                            $running_totals[$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 ];
+                                $running_totals['taxable'][$line_item_id] =
+                                    $line_items_percent_of_running_total * $running_totals['taxable'][$line_item_id];
                             }
                         }
                     }
@@ -1747,8 +1747,8 @@ 
             );
         }
         // ok now find this new registration's final price
-        if (isset($final_prices_per_ticket_line_item[ $ticket_line_item->ID() ])) {
-            return $final_prices_per_ticket_line_item[ $ticket_line_item->ID() ];
+        if (isset($final_prices_per_ticket_line_item[$ticket_line_item->ID()])) {
+            return $final_prices_per_ticket_line_item[$ticket_line_item->ID()];
         }
         $message = sprintf(
             esc_html__(
@@ -1758,7 +1758,7 @@ 
             $ticket_line_item->ID()
         );
         if (WP_DEBUG) {
-            $message .= '<br>' . print_r($final_prices_per_ticket_line_item, true);
+            $message .= '<br>'.print_r($final_prices_per_ticket_line_item, true);
             throw new OutOfRangeException($message);
         }
         EE_Log::instance()->log(__CLASS__, __FUNCTION__, $message);

Indentation +2041 added lines, -2041 removed lines

@@ -21,2045 +21,2045 @@
 class EEH_Line_Item
 {
 
-    /**
-     * 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 boolean      $code if set to a value, ensures there is only one line item with that code
-     * @return boolean success
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function add_unrelated_item(
-        EE_Line_Item $parent_line_item,
-        $name,
-        $unit_price,
-        $description = '',
-        $quantity = 1,
-        $taxable = false,
-        $code = null
-    ) {
-        $items_subtotal = self::get_pre_tax_subtotal($parent_line_item);
-        $line_item = EE_Line_Item::new_instance(array(
-            '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,
-            $parent_line_item
-        );
-        return self::add_item($parent_line_item, $line_item);
-    }
-
-
-    /**
-     * Adds a simple item ( unrelated to any other model object) to the total line item,
-     * in the correct spot 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 $parent_line_item
-     * @param string       $name
-     * @param float        $percentage_amount
-     * @param string       $description
-     * @param boolean      $taxable
-     * @return boolean success
-     * @throws EE_Error
-     */
-    public static function add_percentage_based_item(
-        EE_Line_Item $parent_line_item,
-        $name,
-        $percentage_amount,
-        $description = '',
-        $taxable = false
-    ) {
-        $line_item = EE_Line_Item::new_instance(array(
-            'LIN_name'       => $name,
-            'LIN_desc'       => $description,
-            'LIN_unit_price' => 0,
-            'LIN_percent'    => $percentage_amount,
-            'LIN_quantity'   => 1,
-            'LIN_is_taxable' => $taxable,
-            'LIN_total'      => (float) ($percentage_amount * ($parent_line_item->total() / 100)),
-            'LIN_type'       => EEM_Line_Item::type_line_item,
-            'LIN_parent'     => $parent_line_item->ID(),
-        ));
-        $line_item = apply_filters(
-            'FHEE__EEH_Line_Item__add_percentage_based_item__line_item',
-            $line_item
-        );
-        return $parent_line_item->add_child_line_item($line_item, false);
-    }
-
-
-    /**
-     * 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 $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 InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function add_ticket_purchase(EE_Line_Item $total_line_item, EE_Ticket $ticket, $qty = 1)
-    {
-        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 ((array) $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);
-        // 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' => $ticket->taxable(),
-            'LIN_order'      => count($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
-        );
-        $events_sub_total->add_child_line_item($line_item);
-        // now add the sub-line items
-        $running_total_for_ticket = 0;
-        foreach ($ticket->prices(array('order_by' => array('PRC_order' => 'ASC'))) as $price) {
-            $sign = $price->is_discount() ? -1 : 1;
-            $price_total = $price->is_percent()
-                ? $running_total_for_ticket * $price->amount() / 100
-                : $price->amount() * $qty;
-            $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'      => $sign * $price_total,
-                'LIN_type'       => 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',
-                $sub_line_item
-            );
-            if ($price->is_percent()) {
-                $sub_line_item->set_percent($sign * $price->amount());
-            } else {
-                $sub_line_item->set_unit_price($sign * $price->amount());
-            }
-            $running_total_for_ticket += $price_total;
-            $line_item->add_child_line_item($sub_line_item);
-        }
-        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)
-    {
-        $pre_tax_subtotal = self::get_pre_tax_subtotal($total_line_item);
-        if ($pre_tax_subtotal instanceof EE_Line_Item) {
-            $success = $pre_tax_subtotal->add_child_line_item($item);
-        } else {
-            return false;
-        }
-        $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(
-                    __('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)
-    {
-        /** @type EEM_Price $EEM_Price */
-        $EEM_Price = EE_Registry::instance()->load_model('Price');
-        // get array of taxes via Price Model
-        $ordered_taxes = $EEM_Price->get_all_prices_that_are_taxes();
-        ksort($ordered_taxes);
-        $taxes_line_item = self::get_taxes_subtotal($total_line_item);
-        // just to be safe, remove its old tax line items
-        $deleted = $taxes_line_item->delete_children_line_items();
-        $updates = false;
-        // loop thru taxes
-        foreach ($ordered_taxes as $order => $taxes) {
-            foreach ($taxes as $tax) {
-                if ($tax instanceof EE_Price) {
-                    $tax_line_item = EE_Line_Item::new_instance(
-                        array(
-                            '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(),
-                        )
-                    );
-                    $tax_line_item = apply_filters(
-                        'FHEE__EEH_Line_Item__apply_taxes__tax_line_item',
-                        $tax_line_item
-                    );
-                    $updates = $taxes_line_item->add_child_line_item($tax_line_item) ?
-                        true :
-                        $updates;
-                }
-            }
-        }
-        // only recalculate totals if something changed
-        if ($deleted || $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 ? $name : esc_html__('Tax', 'event_espresso'),
-                'LIN_desc'    => $description ? $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
-     */
-    public static function find_transaction_grand_total_for_line_item(EE_Line_Item $line_item)
-    {
-        if ($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)
-    {
-        echo defined('EE_TESTS_DIR') ? "\n" : '<br />';
-        if (! $indentation) {
-            echo defined('EE_TESTS_DIR') ? "\n" : '<br />';
-        }
-        for ($i = 0; $i < $indentation; $i++) {
-            echo '. ';
-        }
-        $breakdown = '';
-        if ($line_item->is_line_item()) {
-            if ($line_item->is_percent()) {
-                $breakdown = "{$line_item->percent()}%";
-            } else {
-                $breakdown = '$' . "{$line_item->unit_price()} x {$line_item->quantity()}";
-            }
-        }
-        echo $line_item->name();
-        echo " [ ID:{$line_item->ID()} | qty:{$line_item->quantity()} ] {$line_item->type()} : ";
-        echo '$' . (string) $line_item->total();
-        if ($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);
-            }
-        }
-    }
-
-
-    /**
-     * 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)) {
-            $final_prices_per_ticket_line_item = 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[ $ticket_line_item->ID() ])) {
-            return $final_prices_per_ticket_line_item[ $ticket_line_item->ID() ];
-        }
-        $message = sprintf(
-            esc_html__(
-                'The final price for the ticket line item (ID:%1$d) could not be calculated.',
-                'event_espresso'
-            ),
-            $ticket_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 $VID:$
-     * @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();
-                }
-            }
-        }
-    }
-
-
-
-    /**************************************** @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);
-    }
+	/**
+	 * 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 boolean      $code if set to a value, ensures there is only one line item with that code
+	 * @return boolean success
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function add_unrelated_item(
+		EE_Line_Item $parent_line_item,
+		$name,
+		$unit_price,
+		$description = '',
+		$quantity = 1,
+		$taxable = false,
+		$code = null
+	) {
+		$items_subtotal = self::get_pre_tax_subtotal($parent_line_item);
+		$line_item = EE_Line_Item::new_instance(array(
+			'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,
+			$parent_line_item
+		);
+		return self::add_item($parent_line_item, $line_item);
+	}
+
+
+	/**
+	 * Adds a simple item ( unrelated to any other model object) to the total line item,
+	 * in the correct spot 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 $parent_line_item
+	 * @param string       $name
+	 * @param float        $percentage_amount
+	 * @param string       $description
+	 * @param boolean      $taxable
+	 * @return boolean success
+	 * @throws EE_Error
+	 */
+	public static function add_percentage_based_item(
+		EE_Line_Item $parent_line_item,
+		$name,
+		$percentage_amount,
+		$description = '',
+		$taxable = false
+	) {
+		$line_item = EE_Line_Item::new_instance(array(
+			'LIN_name'       => $name,
+			'LIN_desc'       => $description,
+			'LIN_unit_price' => 0,
+			'LIN_percent'    => $percentage_amount,
+			'LIN_quantity'   => 1,
+			'LIN_is_taxable' => $taxable,
+			'LIN_total'      => (float) ($percentage_amount * ($parent_line_item->total() / 100)),
+			'LIN_type'       => EEM_Line_Item::type_line_item,
+			'LIN_parent'     => $parent_line_item->ID(),
+		));
+		$line_item = apply_filters(
+			'FHEE__EEH_Line_Item__add_percentage_based_item__line_item',
+			$line_item
+		);
+		return $parent_line_item->add_child_line_item($line_item, false);
+	}
+
+
+	/**
+	 * 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 $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 InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function add_ticket_purchase(EE_Line_Item $total_line_item, EE_Ticket $ticket, $qty = 1)
+	{
+		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 ((array) $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);
+		// 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' => $ticket->taxable(),
+			'LIN_order'      => count($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
+		);
+		$events_sub_total->add_child_line_item($line_item);
+		// now add the sub-line items
+		$running_total_for_ticket = 0;
+		foreach ($ticket->prices(array('order_by' => array('PRC_order' => 'ASC'))) as $price) {
+			$sign = $price->is_discount() ? -1 : 1;
+			$price_total = $price->is_percent()
+				? $running_total_for_ticket * $price->amount() / 100
+				: $price->amount() * $qty;
+			$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'      => $sign * $price_total,
+				'LIN_type'       => 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',
+				$sub_line_item
+			);
+			if ($price->is_percent()) {
+				$sub_line_item->set_percent($sign * $price->amount());
+			} else {
+				$sub_line_item->set_unit_price($sign * $price->amount());
+			}
+			$running_total_for_ticket += $price_total;
+			$line_item->add_child_line_item($sub_line_item);
+		}
+		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)
+	{
+		$pre_tax_subtotal = self::get_pre_tax_subtotal($total_line_item);
+		if ($pre_tax_subtotal instanceof EE_Line_Item) {
+			$success = $pre_tax_subtotal->add_child_line_item($item);
+		} else {
+			return false;
+		}
+		$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(
+					__('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)
+	{
+		/** @type EEM_Price $EEM_Price */
+		$EEM_Price = EE_Registry::instance()->load_model('Price');
+		// get array of taxes via Price Model
+		$ordered_taxes = $EEM_Price->get_all_prices_that_are_taxes();
+		ksort($ordered_taxes);
+		$taxes_line_item = self::get_taxes_subtotal($total_line_item);
+		// just to be safe, remove its old tax line items
+		$deleted = $taxes_line_item->delete_children_line_items();
+		$updates = false;
+		// loop thru taxes
+		foreach ($ordered_taxes as $order => $taxes) {
+			foreach ($taxes as $tax) {
+				if ($tax instanceof EE_Price) {
+					$tax_line_item = EE_Line_Item::new_instance(
+						array(
+							'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(),
+						)
+					);
+					$tax_line_item = apply_filters(
+						'FHEE__EEH_Line_Item__apply_taxes__tax_line_item',
+						$tax_line_item
+					);
+					$updates = $taxes_line_item->add_child_line_item($tax_line_item) ?
+						true :
+						$updates;
+				}
+			}
+		}
+		// only recalculate totals if something changed
+		if ($deleted || $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 ? $name : esc_html__('Tax', 'event_espresso'),
+				'LIN_desc'    => $description ? $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
+	 */
+	public static function find_transaction_grand_total_for_line_item(EE_Line_Item $line_item)
+	{
+		if ($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)
+	{
+		echo defined('EE_TESTS_DIR') ? "\n" : '<br />';
+		if (! $indentation) {
+			echo defined('EE_TESTS_DIR') ? "\n" : '<br />';
+		}
+		for ($i = 0; $i < $indentation; $i++) {
+			echo '. ';
+		}
+		$breakdown = '';
+		if ($line_item->is_line_item()) {
+			if ($line_item->is_percent()) {
+				$breakdown = "{$line_item->percent()}%";
+			} else {
+				$breakdown = '$' . "{$line_item->unit_price()} x {$line_item->quantity()}";
+			}
+		}
+		echo $line_item->name();
+		echo " [ ID:{$line_item->ID()} | qty:{$line_item->quantity()} ] {$line_item->type()} : ";
+		echo '$' . (string) $line_item->total();
+		if ($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);
+			}
+		}
+	}
+
+
+	/**
+	 * 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)) {
+			$final_prices_per_ticket_line_item = 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[ $ticket_line_item->ID() ])) {
+			return $final_prices_per_ticket_line_item[ $ticket_line_item->ID() ];
+		}
+		$message = sprintf(
+			esc_html__(
+				'The final price for the ticket line item (ID:%1$d) could not be calculated.',
+				'event_espresso'
+			),
+			$ticket_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 $VID:$
+	 * @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();
+				}
+			}
+		}
+	}
+
+
+
+	/**************************************** @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/db_models/EEM_Line_Item.model.php

Spacing +3 added lines, -3 removed lines

@@ -324,8 +324,8 @@ 
         );
         $query = $wpdb->prepare(
             'DELETE li
-				FROM ' . $this->table() . ' li
-				LEFT JOIN ' . EEM_Transaction::instance()->table() . ' t ON li.TXN_ID = t.TXN_ID
+				FROM ' . $this->table().' li
+				LEFT JOIN ' . EEM_Transaction::instance()->table().' t ON li.TXN_ID = t.TXN_ID
 				WHERE t.TXN_ID IS NULL AND li.LIN_timestamp < %s',
             // use GMT time because that's what TXN_timestamps are in
             date('Y-m-d H:i:s', time() - $time_to_leave_alone)
@@ -598,7 +598,7 @@ 
      */
     public function getTicketLineItemsForExpiredCarts($timestamp = 0)
     {
-        if (! absint($timestamp)) {
+        if ( ! absint($timestamp)) {
             /** @var EventEspresso\core\domain\values\session\SessionLifespan $session_lifespan */
             $session_lifespan = LoaderFactory::getLoader()->getShared(
                 'EventEspresso\core\domain\values\session\SessionLifespan'

Indentation +594 added lines, -594 removed lines

@@ -28,601 +28,601 @@
 class EEM_Line_Item extends EEM_Base
 {
 
-    /**
-     * Tax sub-total is just the total of all the taxes, which should be children
-     * of this line item. There should only ever be one tax sub-total, and it should
-     * be a direct child of. Its quantity and LIN_unit_price = 1.
-     */
-    const type_tax_sub_total = 'tax-sub-total';
-
-    /**
-     * Tax line items indicate a tax applied to all the taxable line items.
-     * Should not have any children line items. Its LIN_unit_price = 0. Its LIN_percent is a percent, not a decimal
-     * (eg 10% tax = 10, not 0.1). Its LIN_total = LIN_unit_price * pre-tax-total. Quantity = 1.
-     */
-    const type_tax = 'tax';
-
-    /**
-     * Indicating individual items purchased, or discounts or surcharges.
-     * The sum of all the regular line items  plus the tax items should equal the grand total.
-     * Possible children are sub-line-items and cancellations.
-     * For flat items, LIN_unit_price * LIN_quantity = LIN_total. Its LIN_total is the sum of all the children
-     * LIN_totals. Its LIN_percent = 0.
-     * For percent items, its LIN_unit_price = 0. Its LIN_percent is a percent, not a decimal (eg 10% = 10, not 0.1).
-     * Its LIN_total is LIN_percent / 100 * sum of lower-priority sibling line items. Quantity = 1.
-     */
-    const type_line_item = 'line-item';
-
-    /**
-     * Line item indicating all the factors that make a single line item.
-     * Sub-line items should have NO children line items.
-     * For flat sub-items, their quantity should match their parent item, their LIN_unit_price should be this sub-item's
-     * contribution towards the price of ONE of their parent items, and its LIN_total should be
-     *  = LIN_quantity * LIN_unit_price. Its LIN_percent = 0.
-     * For percent sub-items, the quantity should be 1, LIN_unit_price should be 0, and its LIN_total should
-     * = LIN_percent / 100 * sum of lower-priority sibling line items..
-     */
-    const type_sub_line_item = 'sub-item';
-
-    /**
-     * Line item indicating a sub-total (eg total for an event, or pre-tax subtotal).
-     * Direct children should be event subtotals.
-     * Should have quantity of 1, and a LIN_total and LIN_unit_price of the sum of all its sub-items' LIN_totals.
-     */
-    const type_sub_total = 'sub-total';
-
-    /**
-     * Line item for the grand total of an order.
-     * Its direct children should be tax subtotals and (pre-tax) subtotals,
-     * and possibly a regular line item indicating a transaction-wide discount/surcharge.
-     * Should have a quantity of 1, a LIN_total and LIN_unit_price of the entire order's amount.
-     */
-    const type_total = 'total';
-
-    /**
-     * When a line item is cancelled, a sub-line-item of type 'cancellation'
-     * should be created, indicating the quantity that were cancelled
-     * (because a line item could have a quantity of 1, and its cancellation item
-     * could be for 3, indicating that originally 4 were purchased, but 3 have been
-     * cancelled, and only one remains).
-     * When items are refunded, a cancellation line item should be made, which points
-     * to teh payment model object which actually refunded the payment.
-     * Cancellations should NOT have any children line items; the should NOT affect
-     * any calculations, and are only meant as a record that cancellations have occurred.
-     * Their LIN_percent should be 0.
-     */
-    const type_cancellation = 'cancellation';
-
-    // various line item object types
-    const OBJ_TYPE_EVENT = 'Event';
-
-    const OBJ_TYPE_PRICE = 'Price';
-
-    const OBJ_TYPE_PROMOTION = 'Promotion';
-
-    const OBJ_TYPE_TICKET = 'Ticket';
-
-    const OBJ_TYPE_TRANSACTION = 'Transaction';
-
-    /**
-     * @var EEM_Line_Item $_instance
-     */
-    protected static $_instance;
-
-
-    /**
-     * private constructor to prevent direct creation
-     *
-     * @Constructor
-     * @param string $timezone string representing the timezone we want to set for returned Date Time Strings
-     *                         (and any incoming timezone data that gets saved).
-     *                         Note this just sends the timezone info to the date time model field objects.
-     *                         Default is NULL
-     *                         (and will be assumed using the set timezone in the 'timezone_string' wp option)
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     */
-    protected function __construct($timezone)
-    {
-        $this->singular_item = esc_html__('Line Item', 'event_espresso');
-        $this->plural_item = esc_html__('Line Items', 'event_espresso');
-
-        $this->_tables = array(
-            'Line_Item' => new EE_Primary_Table('esp_line_item', 'LIN_ID'),
-        );
-        $line_items_can_be_for = apply_filters(
-            'FHEE__EEM_Line_Item__line_items_can_be_for',
-            array('Ticket', 'Price', 'Event')
-        );
-        $this->_fields = array(
-            'Line_Item' => array(
-                'LIN_ID'         => new EE_Primary_Key_Int_Field(
-                    'LIN_ID',
-                    esc_html__('ID', 'event_espresso')
-                ),
-                'LIN_code'       => new EE_Slug_Field(
-                    'LIN_code',
-                    esc_html__('Code for index into Cart', 'event_espresso'),
-                    true
-                ),
-                'TXN_ID'         => new EE_Foreign_Key_Int_Field(
-                    'TXN_ID',
-                    esc_html__('Transaction ID', 'event_espresso'),
-                    true,
-                    null,
-                    'Transaction'
-                ),
-                'LIN_name'       => new EE_Full_HTML_Field(
-                    'LIN_name',
-                    esc_html__('Line Item Name', 'event_espresso'),
-                    false,
-                    ''
-                ),
-                'LIN_desc'       => new EE_Full_HTML_Field(
-                    'LIN_desc',
-                    esc_html__('Line Item Description', 'event_espresso'),
-                    true
-                ),
-                'LIN_unit_price' => new EE_Money_Field(
-                    'LIN_unit_price',
-                    esc_html__('Unit Price', 'event_espresso'),
-                    false,
-                    0
-                ),
-                'LIN_percent'    => new EE_Float_Field(
-                    'LIN_percent',
-                    esc_html__('Percent', 'event_espresso'),
-                    false,
-                    0
-                ),
-                'LIN_is_taxable' => new EE_Boolean_Field(
-                    'LIN_is_taxable',
-                    esc_html__('Taxable', 'event_espresso'),
-                    false,
-                    false
-                ),
-                'LIN_order'      => new EE_Integer_Field(
-                    'LIN_order',
-                    esc_html__('Order of Application towards total of parent', 'event_espresso'),
-                    false,
-                    1
-                ),
-                'LIN_total'      => new EE_Money_Field(
-                    'LIN_total',
-                    esc_html__('Total (unit price x quantity)', 'event_espresso'),
-                    false,
-                    0
-                ),
-                'LIN_quantity'   => new EE_Integer_Field(
-                    'LIN_quantity',
-                    esc_html__('Quantity', 'event_espresso'),
-                    true,
-                    1
-                ),
-                'LIN_parent'     => new EE_Integer_Field(
-                    'LIN_parent',
-                    esc_html__("Parent ID (this item goes towards that Line Item's total)", 'event_espresso'),
-                    true,
-                    null
-                ),
-                'LIN_type'       => new EE_Enum_Text_Field(
-                    'LIN_type',
-                    esc_html__('Type', 'event_espresso'),
-                    false,
-                    'line-item',
-                    array(
-                        self::type_line_item     => esc_html__('Line Item', 'event_espresso'),
-                        self::type_sub_line_item => esc_html__('Sub-Item', 'event_espresso'),
-                        self::type_sub_total     => esc_html__('Subtotal', 'event_espresso'),
-                        self::type_tax_sub_total => esc_html__('Tax Subtotal', 'event_espresso'),
-                        self::type_tax           => esc_html__('Tax', 'event_espresso'),
-                        self::type_total         => esc_html__('Total', 'event_espresso'),
-                        self::type_cancellation  => esc_html__('Cancellation', 'event_espresso'),
-                    )
-                ),
-                'OBJ_ID'         => new EE_Foreign_Key_Int_Field(
-                    'OBJ_ID',
-                    esc_html__('ID of Item purchased.', 'event_espresso'),
-                    true,
-                    null,
-                    $line_items_can_be_for
-                ),
-                'OBJ_type'       => new EE_Any_Foreign_Model_Name_Field(
-                    'OBJ_type',
-                    esc_html__('Model Name this Line Item is for', 'event_espresso'),
-                    true,
-                    null,
-                    $line_items_can_be_for
-                ),
-                'LIN_timestamp'  => new EE_Datetime_Field(
-                    'LIN_timestamp',
-                    esc_html__('When the line item was created', 'event_espresso'),
-                    false,
-                    EE_Datetime_Field::now,
-                    $timezone
-                ),
-            ),
-        );
-        $this->_model_relations = array(
-            'Transaction' => new EE_Belongs_To_Relation(),
-            'Ticket'      => new EE_Belongs_To_Any_Relation(),
-            'Price'       => new EE_Belongs_To_Any_Relation(),
-            'Event'       => new EE_Belongs_To_Any_Relation(),
-        );
-        $this->_model_chain_to_wp_user = 'Transaction.Registration.Event';
-        $this->_caps_slug = 'transactions';
-        parent::__construct($timezone);
-    }
-
-
-    /**
-     * Gets all the line items for this transaction of the given type
-     *
-     * @param string             $line_item_type like one of EEM_Line_Item::type_*
-     * @param EE_Transaction|int $transaction
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function get_all_of_type_for_transaction($line_item_type, $transaction)
-    {
-        $transaction = EEM_Transaction::instance()->ensure_is_ID($transaction);
-        return $this->get_all(array(
-            array(
-                'LIN_type' => $line_item_type,
-                'TXN_ID'   => $transaction,
-            ),
-        ));
-    }
-
-
-    /**
-     * Gets all line items unrelated to tickets that are normal line items
-     * (eg shipping, promotions, and miscellaneous other stuff should probably fit in this category)
-     *
-     * @param EE_Transaction|int $transaction
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function get_all_non_ticket_line_items_for_transaction($transaction)
-    {
-        $transaction = EEM_Transaction::instance()->ensure_is_ID($transaction);
-        return $this->get_all(array(
-            array(
-                'LIN_type' => self::type_line_item,
-                'TXN_ID'   => $transaction,
-                'OR'       => array(
-                    'OBJ_type*notticket' => array('!=', EEM_Line_Item::OBJ_TYPE_TICKET),
-                    'OBJ_type*null'      => array('IS_NULL'),
-                ),
-            ),
-        ));
-    }
-
-
-    /**
-     * Deletes line items with no transaction who have passed the transaction cutoff time.
-     * This needs to be very efficient
-     * because if there are spam bots afoot there will be LOTS of line items
-     *
-     * @return int count of how many deleted
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function delete_line_items_with_no_transaction()
-    {
-        /** @type WPDB $wpdb */
-        global $wpdb;
-        $time_to_leave_alone = apply_filters(
-            'FHEE__EEM_Line_Item__delete_line_items_with_no_transaction__time_to_leave_alone',
-            WEEK_IN_SECONDS
-        );
-        $query = $wpdb->prepare(
-            'DELETE li
+	/**
+	 * Tax sub-total is just the total of all the taxes, which should be children
+	 * of this line item. There should only ever be one tax sub-total, and it should
+	 * be a direct child of. Its quantity and LIN_unit_price = 1.
+	 */
+	const type_tax_sub_total = 'tax-sub-total';
+
+	/**
+	 * Tax line items indicate a tax applied to all the taxable line items.
+	 * Should not have any children line items. Its LIN_unit_price = 0. Its LIN_percent is a percent, not a decimal
+	 * (eg 10% tax = 10, not 0.1). Its LIN_total = LIN_unit_price * pre-tax-total. Quantity = 1.
+	 */
+	const type_tax = 'tax';
+
+	/**
+	 * Indicating individual items purchased, or discounts or surcharges.
+	 * The sum of all the regular line items  plus the tax items should equal the grand total.
+	 * Possible children are sub-line-items and cancellations.
+	 * For flat items, LIN_unit_price * LIN_quantity = LIN_total. Its LIN_total is the sum of all the children
+	 * LIN_totals. Its LIN_percent = 0.
+	 * For percent items, its LIN_unit_price = 0. Its LIN_percent is a percent, not a decimal (eg 10% = 10, not 0.1).
+	 * Its LIN_total is LIN_percent / 100 * sum of lower-priority sibling line items. Quantity = 1.
+	 */
+	const type_line_item = 'line-item';
+
+	/**
+	 * Line item indicating all the factors that make a single line item.
+	 * Sub-line items should have NO children line items.
+	 * For flat sub-items, their quantity should match their parent item, their LIN_unit_price should be this sub-item's
+	 * contribution towards the price of ONE of their parent items, and its LIN_total should be
+	 *  = LIN_quantity * LIN_unit_price. Its LIN_percent = 0.
+	 * For percent sub-items, the quantity should be 1, LIN_unit_price should be 0, and its LIN_total should
+	 * = LIN_percent / 100 * sum of lower-priority sibling line items..
+	 */
+	const type_sub_line_item = 'sub-item';
+
+	/**
+	 * Line item indicating a sub-total (eg total for an event, or pre-tax subtotal).
+	 * Direct children should be event subtotals.
+	 * Should have quantity of 1, and a LIN_total and LIN_unit_price of the sum of all its sub-items' LIN_totals.
+	 */
+	const type_sub_total = 'sub-total';
+
+	/**
+	 * Line item for the grand total of an order.
+	 * Its direct children should be tax subtotals and (pre-tax) subtotals,
+	 * and possibly a regular line item indicating a transaction-wide discount/surcharge.
+	 * Should have a quantity of 1, a LIN_total and LIN_unit_price of the entire order's amount.
+	 */
+	const type_total = 'total';
+
+	/**
+	 * When a line item is cancelled, a sub-line-item of type 'cancellation'
+	 * should be created, indicating the quantity that were cancelled
+	 * (because a line item could have a quantity of 1, and its cancellation item
+	 * could be for 3, indicating that originally 4 were purchased, but 3 have been
+	 * cancelled, and only one remains).
+	 * When items are refunded, a cancellation line item should be made, which points
+	 * to teh payment model object which actually refunded the payment.
+	 * Cancellations should NOT have any children line items; the should NOT affect
+	 * any calculations, and are only meant as a record that cancellations have occurred.
+	 * Their LIN_percent should be 0.
+	 */
+	const type_cancellation = 'cancellation';
+
+	// various line item object types
+	const OBJ_TYPE_EVENT = 'Event';
+
+	const OBJ_TYPE_PRICE = 'Price';
+
+	const OBJ_TYPE_PROMOTION = 'Promotion';
+
+	const OBJ_TYPE_TICKET = 'Ticket';
+
+	const OBJ_TYPE_TRANSACTION = 'Transaction';
+
+	/**
+	 * @var EEM_Line_Item $_instance
+	 */
+	protected static $_instance;
+
+
+	/**
+	 * private constructor to prevent direct creation
+	 *
+	 * @Constructor
+	 * @param string $timezone string representing the timezone we want to set for returned Date Time Strings
+	 *                         (and any incoming timezone data that gets saved).
+	 *                         Note this just sends the timezone info to the date time model field objects.
+	 *                         Default is NULL
+	 *                         (and will be assumed using the set timezone in the 'timezone_string' wp option)
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 */
+	protected function __construct($timezone)
+	{
+		$this->singular_item = esc_html__('Line Item', 'event_espresso');
+		$this->plural_item = esc_html__('Line Items', 'event_espresso');
+
+		$this->_tables = array(
+			'Line_Item' => new EE_Primary_Table('esp_line_item', 'LIN_ID'),
+		);
+		$line_items_can_be_for = apply_filters(
+			'FHEE__EEM_Line_Item__line_items_can_be_for',
+			array('Ticket', 'Price', 'Event')
+		);
+		$this->_fields = array(
+			'Line_Item' => array(
+				'LIN_ID'         => new EE_Primary_Key_Int_Field(
+					'LIN_ID',
+					esc_html__('ID', 'event_espresso')
+				),
+				'LIN_code'       => new EE_Slug_Field(
+					'LIN_code',
+					esc_html__('Code for index into Cart', 'event_espresso'),
+					true
+				),
+				'TXN_ID'         => new EE_Foreign_Key_Int_Field(
+					'TXN_ID',
+					esc_html__('Transaction ID', 'event_espresso'),
+					true,
+					null,
+					'Transaction'
+				),
+				'LIN_name'       => new EE_Full_HTML_Field(
+					'LIN_name',
+					esc_html__('Line Item Name', 'event_espresso'),
+					false,
+					''
+				),
+				'LIN_desc'       => new EE_Full_HTML_Field(
+					'LIN_desc',
+					esc_html__('Line Item Description', 'event_espresso'),
+					true
+				),
+				'LIN_unit_price' => new EE_Money_Field(
+					'LIN_unit_price',
+					esc_html__('Unit Price', 'event_espresso'),
+					false,
+					0
+				),
+				'LIN_percent'    => new EE_Float_Field(
+					'LIN_percent',
+					esc_html__('Percent', 'event_espresso'),
+					false,
+					0
+				),
+				'LIN_is_taxable' => new EE_Boolean_Field(
+					'LIN_is_taxable',
+					esc_html__('Taxable', 'event_espresso'),
+					false,
+					false
+				),
+				'LIN_order'      => new EE_Integer_Field(
+					'LIN_order',
+					esc_html__('Order of Application towards total of parent', 'event_espresso'),
+					false,
+					1
+				),
+				'LIN_total'      => new EE_Money_Field(
+					'LIN_total',
+					esc_html__('Total (unit price x quantity)', 'event_espresso'),
+					false,
+					0
+				),
+				'LIN_quantity'   => new EE_Integer_Field(
+					'LIN_quantity',
+					esc_html__('Quantity', 'event_espresso'),
+					true,
+					1
+				),
+				'LIN_parent'     => new EE_Integer_Field(
+					'LIN_parent',
+					esc_html__("Parent ID (this item goes towards that Line Item's total)", 'event_espresso'),
+					true,
+					null
+				),
+				'LIN_type'       => new EE_Enum_Text_Field(
+					'LIN_type',
+					esc_html__('Type', 'event_espresso'),
+					false,
+					'line-item',
+					array(
+						self::type_line_item     => esc_html__('Line Item', 'event_espresso'),
+						self::type_sub_line_item => esc_html__('Sub-Item', 'event_espresso'),
+						self::type_sub_total     => esc_html__('Subtotal', 'event_espresso'),
+						self::type_tax_sub_total => esc_html__('Tax Subtotal', 'event_espresso'),
+						self::type_tax           => esc_html__('Tax', 'event_espresso'),
+						self::type_total         => esc_html__('Total', 'event_espresso'),
+						self::type_cancellation  => esc_html__('Cancellation', 'event_espresso'),
+					)
+				),
+				'OBJ_ID'         => new EE_Foreign_Key_Int_Field(
+					'OBJ_ID',
+					esc_html__('ID of Item purchased.', 'event_espresso'),
+					true,
+					null,
+					$line_items_can_be_for
+				),
+				'OBJ_type'       => new EE_Any_Foreign_Model_Name_Field(
+					'OBJ_type',
+					esc_html__('Model Name this Line Item is for', 'event_espresso'),
+					true,
+					null,
+					$line_items_can_be_for
+				),
+				'LIN_timestamp'  => new EE_Datetime_Field(
+					'LIN_timestamp',
+					esc_html__('When the line item was created', 'event_espresso'),
+					false,
+					EE_Datetime_Field::now,
+					$timezone
+				),
+			),
+		);
+		$this->_model_relations = array(
+			'Transaction' => new EE_Belongs_To_Relation(),
+			'Ticket'      => new EE_Belongs_To_Any_Relation(),
+			'Price'       => new EE_Belongs_To_Any_Relation(),
+			'Event'       => new EE_Belongs_To_Any_Relation(),
+		);
+		$this->_model_chain_to_wp_user = 'Transaction.Registration.Event';
+		$this->_caps_slug = 'transactions';
+		parent::__construct($timezone);
+	}
+
+
+	/**
+	 * Gets all the line items for this transaction of the given type
+	 *
+	 * @param string             $line_item_type like one of EEM_Line_Item::type_*
+	 * @param EE_Transaction|int $transaction
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function get_all_of_type_for_transaction($line_item_type, $transaction)
+	{
+		$transaction = EEM_Transaction::instance()->ensure_is_ID($transaction);
+		return $this->get_all(array(
+			array(
+				'LIN_type' => $line_item_type,
+				'TXN_ID'   => $transaction,
+			),
+		));
+	}
+
+
+	/**
+	 * Gets all line items unrelated to tickets that are normal line items
+	 * (eg shipping, promotions, and miscellaneous other stuff should probably fit in this category)
+	 *
+	 * @param EE_Transaction|int $transaction
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function get_all_non_ticket_line_items_for_transaction($transaction)
+	{
+		$transaction = EEM_Transaction::instance()->ensure_is_ID($transaction);
+		return $this->get_all(array(
+			array(
+				'LIN_type' => self::type_line_item,
+				'TXN_ID'   => $transaction,
+				'OR'       => array(
+					'OBJ_type*notticket' => array('!=', EEM_Line_Item::OBJ_TYPE_TICKET),
+					'OBJ_type*null'      => array('IS_NULL'),
+				),
+			),
+		));
+	}
+
+
+	/**
+	 * Deletes line items with no transaction who have passed the transaction cutoff time.
+	 * This needs to be very efficient
+	 * because if there are spam bots afoot there will be LOTS of line items
+	 *
+	 * @return int count of how many deleted
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function delete_line_items_with_no_transaction()
+	{
+		/** @type WPDB $wpdb */
+		global $wpdb;
+		$time_to_leave_alone = apply_filters(
+			'FHEE__EEM_Line_Item__delete_line_items_with_no_transaction__time_to_leave_alone',
+			WEEK_IN_SECONDS
+		);
+		$query = $wpdb->prepare(
+			'DELETE li
 				FROM ' . $this->table() . ' li
 				LEFT JOIN ' . EEM_Transaction::instance()->table() . ' t ON li.TXN_ID = t.TXN_ID
 				WHERE t.TXN_ID IS NULL AND li.LIN_timestamp < %s',
-            // use GMT time because that's what TXN_timestamps are in
-            date('Y-m-d H:i:s', time() - $time_to_leave_alone)
-        );
-        return $wpdb->query($query);
-    }
-
-
-    /**
-     * get_line_item_for_transaction_object
-     * Gets a transaction's line item record for a specific object such as a EE_Event or EE_Ticket
-     *
-     * @param int           $TXN_ID
-     * @param EE_Base_Class $object
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_line_item_for_transaction_object($TXN_ID, EE_Base_Class $object)
-    {
-        return $this->get_all(array(
-            array(
-                'TXN_ID'   => $TXN_ID,
-                'OBJ_type' => str_replace('EE_', '', get_class($object)),
-                'OBJ_ID'   => $object->ID(),
-            ),
-        ));
-    }
-
-
-    /**
-     * get_object_line_items_for_transaction
-     * Gets all of the the object line items for a transaction, based on an object type plus an array of object IDs
-     *
-     * @param int    $TXN_ID
-     * @param string $OBJ_type
-     * @param array  $OBJ_IDs
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     */
-    public function get_object_line_items_for_transaction(
-        $TXN_ID,
-        $OBJ_type = EEM_Line_Item::OBJ_TYPE_EVENT,
-        $OBJ_IDs = array()
-    ) {
-        $query_params = array(
-            'OBJ_type' => $OBJ_type,
-            // if incoming $OBJ_IDs is an array, then make sure it is formatted correctly for the query
-            'OBJ_ID'   => is_array($OBJ_IDs) && ! isset($OBJ_IDs['IN']) ? array('IN', $OBJ_IDs) : $OBJ_IDs,
-        );
-        if ($TXN_ID) {
-            $query_params['TXN_ID'] = $TXN_ID;
-        }
-        return $this->get_all(array($query_params));
-    }
-
-
-    /**
-     * get_all_ticket_line_items_for_transaction
-     *
-     * @param EE_Transaction $transaction
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_all_ticket_line_items_for_transaction(EE_Transaction $transaction)
-    {
-        return $this->get_all(array(
-            array(
-                'TXN_ID'   => $transaction->ID(),
-                'OBJ_type' => EEM_Line_Item::OBJ_TYPE_TICKET,
-            ),
-        ));
-    }
-
-
-    /**
-     * get_ticket_line_item_for_transaction
-     *
-     * @param int $TXN_ID
-     * @param int $TKT_ID
-     * @return EE_Base_Class|EE_Line_Item|EE_Soft_Delete_Base_Class|NULL
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function get_ticket_line_item_for_transaction($TXN_ID, $TKT_ID)
-    {
-        return $this->get_one(array(
-            array(
-                'TXN_ID'   => EEM_Transaction::instance()->ensure_is_ID($TXN_ID),
-                'OBJ_ID'   => $TKT_ID,
-                'OBJ_type' => EEM_Line_Item::OBJ_TYPE_TICKET,
-            ),
-        ));
-    }
-
-
-    /**
-     * get_existing_promotion_line_item
-     * searches the cart for existing line items for the specified promotion
-     *
-     * @since 1.0.0
-     * @param EE_Line_Item $parent_line_item
-     * @param EE_Promotion $promotion
-     * @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_existing_promotion_line_item(EE_Line_Item $parent_line_item, EE_Promotion $promotion)
-    {
-        return $this->get_one(array(
-            array(
-                'TXN_ID'     => $parent_line_item->TXN_ID(),
-                'LIN_parent' => $parent_line_item->ID(),
-                'OBJ_type'   => EEM_Line_Item::OBJ_TYPE_PROMOTION,
-                'OBJ_ID'     => $promotion->ID(),
-            ),
-        ));
-    }
-
-
-    /**
-     * get_all_promotion_line_items
-     * searches the cart for any and all existing promotion line items
-     *
-     * @since   1.0.0
-     * @param EE_Line_Item $parent_line_item
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_all_promotion_line_items(EE_Line_Item $parent_line_item)
-    {
-        return $this->get_all(array(
-            array(
-                'TXN_ID'     => $parent_line_item->TXN_ID(),
-                'LIN_parent' => $parent_line_item->ID(),
-                'OBJ_type'   => EEM_Line_Item::OBJ_TYPE_PROMOTION,
-            ),
-        ));
-    }
-
-
-    /**
-     * Gets the registration's corresponding line item.
-     * Note: basically does NOT support having multiple line items for a single ticket,
-     * which would happen if some of the registrations had a price modifier while others didn't.
-     * In order to support that, we'd probably need a LIN_ID on registrations or something.
-     *
-     * @param EE_Registration $registration
-     * @return EE_Base_Class|EE_Line_ITem|EE_Soft_Delete_Base_Class|NULL
-     * @throws EE_Error
-     */
-    public function get_line_item_for_registration(EE_Registration $registration)
-    {
-        return $this->get_one($this->line_item_for_registration_query_params($registration));
-    }
-
-
-    /**
-     * Gets the query params used to retrieve a specific line item for the given registration
-     *
-     * @param EE_Registration $registration
-     * @param array           $original_query_params any extra query params you'd like to be merged with
-     * @return array @see
-     *      https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @throws EE_Error
-     */
-    public function line_item_for_registration_query_params(
-        EE_Registration $registration,
-        $original_query_params = array()
-    ) {
-        return array_replace_recursive($original_query_params, array(
-            array(
-                'OBJ_ID'   => $registration->ticket_ID(),
-                'OBJ_type' => EEM_Line_Item::OBJ_TYPE_TICKET,
-                'TXN_ID'   => $registration->transaction_ID(),
-            ),
-        ));
-    }
-
-
-    /**
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     */
-    public function get_total_line_items_with_no_transaction()
-    {
-        return $this->get_total_line_items_for_carts();
-    }
-
-
-    /**
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     */
-    public function get_total_line_items_for_active_carts()
-    {
-        return $this->get_total_line_items_for_carts(false);
-    }
-
-
-    /**
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     */
-    public function get_total_line_items_for_expired_carts()
-    {
-        return $this->get_total_line_items_for_carts(true);
-    }
-
-
-    /**
-     * Returns an array of grand total line items where the TXN_ID is 0.
-     * If $expired is set to true, then only line items for expired sessions will be returned.
-     * If $expired is set to false, then only line items for active sessions will be returned.
-     *
-     * @param null $expired
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    private function get_total_line_items_for_carts($expired = null)
-    {
-        $where_params = array(
-            'TXN_ID'   => 0,
-            'LIN_type' => 'total',
-        );
-        if ($expired !== null) {
-            /** @var EventEspresso\core\domain\values\session\SessionLifespan $session_lifespan */
-            $session_lifespan = LoaderFactory::getLoader()->getShared(
-                'EventEspresso\core\domain\values\session\SessionLifespan'
-            );
-            $where_params['LIN_timestamp'] = array(
-                $expired ? '<=' : '>',
-                $session_lifespan->expiration(),
-            );
-        }
-        return $this->get_all(array($where_params));
-    }
-
-
-    /**
-     * Returns an array of ticket total line items where the TXN_ID is 0
-     * AND the timestamp is older than the session lifespan.
-     *
-     * @param int $timestamp
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function getTicketLineItemsForExpiredCarts($timestamp = 0)
-    {
-        if (! absint($timestamp)) {
-            /** @var EventEspresso\core\domain\values\session\SessionLifespan $session_lifespan */
-            $session_lifespan = LoaderFactory::getLoader()->getShared(
-                'EventEspresso\core\domain\values\session\SessionLifespan'
-            );
-            $timestamp = $session_lifespan->expiration();
-        }
-        return $this->get_all(
-            array(
-                array(
-                    'TXN_ID'        => 0,
-                    'OBJ_type'      => EEM_Line_Item::OBJ_TYPE_TICKET,
-                    'LIN_timestamp' => array('<=', $timestamp),
-                ),
-            )
-        );
-    }
+			// use GMT time because that's what TXN_timestamps are in
+			date('Y-m-d H:i:s', time() - $time_to_leave_alone)
+		);
+		return $wpdb->query($query);
+	}
+
+
+	/**
+	 * get_line_item_for_transaction_object
+	 * Gets a transaction's line item record for a specific object such as a EE_Event or EE_Ticket
+	 *
+	 * @param int           $TXN_ID
+	 * @param EE_Base_Class $object
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_line_item_for_transaction_object($TXN_ID, EE_Base_Class $object)
+	{
+		return $this->get_all(array(
+			array(
+				'TXN_ID'   => $TXN_ID,
+				'OBJ_type' => str_replace('EE_', '', get_class($object)),
+				'OBJ_ID'   => $object->ID(),
+			),
+		));
+	}
+
+
+	/**
+	 * get_object_line_items_for_transaction
+	 * Gets all of the the object line items for a transaction, based on an object type plus an array of object IDs
+	 *
+	 * @param int    $TXN_ID
+	 * @param string $OBJ_type
+	 * @param array  $OBJ_IDs
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 */
+	public function get_object_line_items_for_transaction(
+		$TXN_ID,
+		$OBJ_type = EEM_Line_Item::OBJ_TYPE_EVENT,
+		$OBJ_IDs = array()
+	) {
+		$query_params = array(
+			'OBJ_type' => $OBJ_type,
+			// if incoming $OBJ_IDs is an array, then make sure it is formatted correctly for the query
+			'OBJ_ID'   => is_array($OBJ_IDs) && ! isset($OBJ_IDs['IN']) ? array('IN', $OBJ_IDs) : $OBJ_IDs,
+		);
+		if ($TXN_ID) {
+			$query_params['TXN_ID'] = $TXN_ID;
+		}
+		return $this->get_all(array($query_params));
+	}
+
+
+	/**
+	 * get_all_ticket_line_items_for_transaction
+	 *
+	 * @param EE_Transaction $transaction
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_all_ticket_line_items_for_transaction(EE_Transaction $transaction)
+	{
+		return $this->get_all(array(
+			array(
+				'TXN_ID'   => $transaction->ID(),
+				'OBJ_type' => EEM_Line_Item::OBJ_TYPE_TICKET,
+			),
+		));
+	}
+
+
+	/**
+	 * get_ticket_line_item_for_transaction
+	 *
+	 * @param int $TXN_ID
+	 * @param int $TKT_ID
+	 * @return EE_Base_Class|EE_Line_Item|EE_Soft_Delete_Base_Class|NULL
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function get_ticket_line_item_for_transaction($TXN_ID, $TKT_ID)
+	{
+		return $this->get_one(array(
+			array(
+				'TXN_ID'   => EEM_Transaction::instance()->ensure_is_ID($TXN_ID),
+				'OBJ_ID'   => $TKT_ID,
+				'OBJ_type' => EEM_Line_Item::OBJ_TYPE_TICKET,
+			),
+		));
+	}
+
+
+	/**
+	 * get_existing_promotion_line_item
+	 * searches the cart for existing line items for the specified promotion
+	 *
+	 * @since 1.0.0
+	 * @param EE_Line_Item $parent_line_item
+	 * @param EE_Promotion $promotion
+	 * @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_existing_promotion_line_item(EE_Line_Item $parent_line_item, EE_Promotion $promotion)
+	{
+		return $this->get_one(array(
+			array(
+				'TXN_ID'     => $parent_line_item->TXN_ID(),
+				'LIN_parent' => $parent_line_item->ID(),
+				'OBJ_type'   => EEM_Line_Item::OBJ_TYPE_PROMOTION,
+				'OBJ_ID'     => $promotion->ID(),
+			),
+		));
+	}
+
+
+	/**
+	 * get_all_promotion_line_items
+	 * searches the cart for any and all existing promotion line items
+	 *
+	 * @since   1.0.0
+	 * @param EE_Line_Item $parent_line_item
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_all_promotion_line_items(EE_Line_Item $parent_line_item)
+	{
+		return $this->get_all(array(
+			array(
+				'TXN_ID'     => $parent_line_item->TXN_ID(),
+				'LIN_parent' => $parent_line_item->ID(),
+				'OBJ_type'   => EEM_Line_Item::OBJ_TYPE_PROMOTION,
+			),
+		));
+	}
+
+
+	/**
+	 * Gets the registration's corresponding line item.
+	 * Note: basically does NOT support having multiple line items for a single ticket,
+	 * which would happen if some of the registrations had a price modifier while others didn't.
+	 * In order to support that, we'd probably need a LIN_ID on registrations or something.
+	 *
+	 * @param EE_Registration $registration
+	 * @return EE_Base_Class|EE_Line_ITem|EE_Soft_Delete_Base_Class|NULL
+	 * @throws EE_Error
+	 */
+	public function get_line_item_for_registration(EE_Registration $registration)
+	{
+		return $this->get_one($this->line_item_for_registration_query_params($registration));
+	}
+
+
+	/**
+	 * Gets the query params used to retrieve a specific line item for the given registration
+	 *
+	 * @param EE_Registration $registration
+	 * @param array           $original_query_params any extra query params you'd like to be merged with
+	 * @return array @see
+	 *      https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @throws EE_Error
+	 */
+	public function line_item_for_registration_query_params(
+		EE_Registration $registration,
+		$original_query_params = array()
+	) {
+		return array_replace_recursive($original_query_params, array(
+			array(
+				'OBJ_ID'   => $registration->ticket_ID(),
+				'OBJ_type' => EEM_Line_Item::OBJ_TYPE_TICKET,
+				'TXN_ID'   => $registration->transaction_ID(),
+			),
+		));
+	}
+
+
+	/**
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 */
+	public function get_total_line_items_with_no_transaction()
+	{
+		return $this->get_total_line_items_for_carts();
+	}
+
+
+	/**
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 */
+	public function get_total_line_items_for_active_carts()
+	{
+		return $this->get_total_line_items_for_carts(false);
+	}
+
+
+	/**
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 */
+	public function get_total_line_items_for_expired_carts()
+	{
+		return $this->get_total_line_items_for_carts(true);
+	}
+
+
+	/**
+	 * Returns an array of grand total line items where the TXN_ID is 0.
+	 * If $expired is set to true, then only line items for expired sessions will be returned.
+	 * If $expired is set to false, then only line items for active sessions will be returned.
+	 *
+	 * @param null $expired
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	private function get_total_line_items_for_carts($expired = null)
+	{
+		$where_params = array(
+			'TXN_ID'   => 0,
+			'LIN_type' => 'total',
+		);
+		if ($expired !== null) {
+			/** @var EventEspresso\core\domain\values\session\SessionLifespan $session_lifespan */
+			$session_lifespan = LoaderFactory::getLoader()->getShared(
+				'EventEspresso\core\domain\values\session\SessionLifespan'
+			);
+			$where_params['LIN_timestamp'] = array(
+				$expired ? '<=' : '>',
+				$session_lifespan->expiration(),
+			);
+		}
+		return $this->get_all(array($where_params));
+	}
+
+
+	/**
+	 * Returns an array of ticket total line items where the TXN_ID is 0
+	 * AND the timestamp is older than the session lifespan.
+	 *
+	 * @param int $timestamp
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function getTicketLineItemsForExpiredCarts($timestamp = 0)
+	{
+		if (! absint($timestamp)) {
+			/** @var EventEspresso\core\domain\values\session\SessionLifespan $session_lifespan */
+			$session_lifespan = LoaderFactory::getLoader()->getShared(
+				'EventEspresso\core\domain\values\session\SessionLifespan'
+			);
+			$timestamp = $session_lifespan->expiration();
+		}
+		return $this->get_all(
+			array(
+				array(
+					'TXN_ID'        => 0,
+					'OBJ_type'      => EEM_Line_Item::OBJ_TYPE_TICKET,
+					'LIN_timestamp' => array('<=', $timestamp),
+				),
+			)
+		);
+	}
 }

admin_pages/transactions/Transactions_Admin_Page.core.php

Spacing +84 added lines, -84 removed lines

@@ -356,7 +356,7 @@ 
         // enqueue style
         wp_register_style(
             'espresso_txn',
-            TXN_ASSETS_URL . 'espresso_transactions_admin.css',
+            TXN_ASSETS_URL.'espresso_transactions_admin.css',
             array(),
             EVENT_ESPRESSO_VERSION
         );
@@ -364,7 +364,7 @@ 
         // scripts
         wp_register_script(
             'espresso_txn',
-            TXN_ASSETS_URL . 'espresso_transactions_admin.js',
+            TXN_ASSETS_URL.'espresso_transactions_admin.js',
             array(
                 'ee_admin_js',
                 'ee-datepicker',
@@ -492,7 +492,7 @@ 
             $this->_transaction->verify_abandoned_transaction_status();
         }
 
-        if (! $this->_transaction instanceof EE_Transaction) {
+        if ( ! $this->_transaction instanceof EE_Transaction) {
             $error_msg = sprintf(
                 esc_html__(
                     'An error occurred and the details for the transaction with the ID # %d could not be retrieved.',
@@ -585,7 +585,7 @@ 
             'FHEE__Transactions_Admin_Page___transaction_legend_items__more_items',
             array(
                 'overpaid'   => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::overpaid_status_code,
+                    'class' => 'ee-status-legend ee-status-legend-'.EEM_Transaction::overpaid_status_code,
                     'desc'  => EEH_Template::pretty_status(
                         EEM_Transaction::overpaid_status_code,
                         false,
@@ -593,7 +593,7 @@ 
                     ),
                 ),
                 'complete'   => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::complete_status_code,
+                    'class' => 'ee-status-legend ee-status-legend-'.EEM_Transaction::complete_status_code,
                     'desc'  => EEH_Template::pretty_status(
                         EEM_Transaction::complete_status_code,
                         false,
@@ -601,7 +601,7 @@ 
                     ),
                 ),
                 'incomplete' => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::incomplete_status_code,
+                    'class' => 'ee-status-legend ee-status-legend-'.EEM_Transaction::incomplete_status_code,
                     'desc'  => EEH_Template::pretty_status(
                         EEM_Transaction::incomplete_status_code,
                         false,
@@ -609,7 +609,7 @@ 
                     ),
                 ),
                 'abandoned'  => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::abandoned_status_code,
+                    'class' => 'ee-status-legend ee-status-legend-'.EEM_Transaction::abandoned_status_code,
                     'desc'  => EEH_Template::pretty_status(
                         EEM_Transaction::abandoned_status_code,
                         false,
@@ -617,7 +617,7 @@ 
                     ),
                 ),
                 'failed'     => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::failed_status_code,
+                    'class' => 'ee-status-legend ee-status-legend-'.EEM_Transaction::failed_status_code,
                     'desc'  => EEH_Template::pretty_status(
                         EEM_Transaction::failed_status_code,
                         false,
@@ -666,7 +666,7 @@ 
                     'Click to Edit event',
                     'event_espresso'
                 )
-                . '">' . $event->name() . '</a>',
+                . '">'.$event->name().'</a>',
                 '</h3>'
             )
             : '';
@@ -700,7 +700,7 @@ 
 
         $this->_set_transaction_object();
 
-        if (! $this->_transaction instanceof EE_Transaction) {
+        if ( ! $this->_transaction instanceof EE_Transaction) {
             return;
         }
         $primary_registration = $this->_transaction->primary_registration();
@@ -714,9 +714,9 @@ 
         $this->_template_args['txn_datetime']['value'] = $this->_transaction->get_i18n_datetime('TXN_timestamp');
         $this->_template_args['txn_datetime']['label'] = esc_html__('Date', 'event_espresso');
 
-        $this->_template_args['txn_status']['value'] = self::$_txn_status[ $this->_transaction->status_ID() ];
+        $this->_template_args['txn_status']['value'] = self::$_txn_status[$this->_transaction->status_ID()];
         $this->_template_args['txn_status']['label'] = esc_html__('Transaction Status', 'event_espresso');
-        $this->_template_args['txn_status']['class'] = 'status-' . $this->_transaction->status_ID();
+        $this->_template_args['txn_status']['class'] = 'status-'.$this->_transaction->status_ID();
 
         $this->_template_args['grand_total'] = $this->_transaction->total();
         $this->_template_args['total_paid'] = $this->_transaction->paid();
@@ -832,7 +832,7 @@ 
         // grab messages at the last second
         $this->_template_args['notices'] = EE_Error::get_notices();
         // path to template
-        $template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_header.template.php';
+        $template_path = TXN_TEMPLATE_PATH.'txn_admin_details_header.template.php';
         $this->_template_args['admin_page_header'] = EEH_Template::display_template(
             $template_path,
             $this->_template_args,
@@ -861,7 +861,7 @@ 
 
         $this->_set_transaction_object();
 
-        if (! $this->_transaction instanceof EE_Transaction) {
+        if ( ! $this->_transaction instanceof EE_Transaction) {
             return;
         }
         add_meta_box(
@@ -917,7 +917,7 @@ 
     {
         $content = '';
         $actions = array();
-        if (! $transaction instanceof EE_Transaction) {
+        if ( ! $transaction instanceof EE_Transaction) {
             return $content;
         }
         /** @var EE_Registration $primary_registration */
@@ -998,7 +998,7 @@ 
         );
         if ($actions) {
             $content = '<ul>';
-            $content .= '<li>' . implode('</li><li>', $actions) . '</li>';
+            $content .= '<li>'.implode('</li><li>', $actions).'</li>';
             $content .= '</uL>';
         }
         return $content;
@@ -1059,7 +1059,7 @@ 
 
         // process payment details
         $payments = $this->_transaction->payments();
-        if (! empty($payments)) {
+        if ( ! empty($payments)) {
             $this->_template_args['payments'] = $payments;
             $this->_template_args['existing_reg_payments'] = $this->_get_registration_payment_IDs($payments);
         } else {
@@ -1120,7 +1120,7 @@ 
                                   esc_html__('%1$s : Initiated %2$s', 'event_espresso'),
                                   ucwords(str_replace('_', ' ', $reg_step)),
                                   date(
-                                      get_option('date_format') . ' ' . get_option('time_format'),
+                                      get_option('date_format').' '.get_option('time_format'),
                                       $reg_step_status + (get_option('gmt_offset') * HOUR_IN_SECONDS)
                                   )
                               )
@@ -1173,7 +1173,7 @@ 
 
         // 'espresso_delete_payment_nonce'
 
-        $template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_main_meta_box_txn_details.template.php';
+        $template_path = TXN_TEMPLATE_PATH.'txn_admin_details_main_meta_box_txn_details.template.php';
         echo EEH_Template::display_template($template_path, $this->_template_args, true);
     }
 
@@ -1205,18 +1205,18 @@ 
                 ),
             )
         );
-        if (! empty($reg_payments)) {
+        if ( ! empty($reg_payments)) {
             foreach ($payments as $payment) {
-                if (! $payment instanceof EE_Payment) {
+                if ( ! $payment instanceof EE_Payment) {
                     continue;
-                } elseif (! isset($existing_reg_payments[ $payment->ID() ])) {
-                    $existing_reg_payments[ $payment->ID() ] = array();
+                } elseif ( ! isset($existing_reg_payments[$payment->ID()])) {
+                    $existing_reg_payments[$payment->ID()] = array();
                 }
                 foreach ($reg_payments as $reg_payment) {
                     if ($reg_payment instanceof EE_Registration_Payment
                         && $reg_payment->payment_ID() === $payment->ID()
                     ) {
-                        $existing_reg_payments[ $payment->ID() ][] = $reg_payment->registration_ID();
+                        $existing_reg_payments[$payment->ID()][] = $reg_payment->registration_ID();
                     }
                 }
             }
@@ -1254,22 +1254,22 @@ 
                 ),
             ),
         );
-        $registrations_to_apply_payment_to = EEH_HTML::br() . EEH_HTML::div(
+        $registrations_to_apply_payment_to = EEH_HTML::br().EEH_HTML::div(
             '',
             'txn-admin-apply-payment-to-registrations-dv',
             '',
             'clear: both; margin: 1.5em 0 0; display: none;'
         );
-        $registrations_to_apply_payment_to .= EEH_HTML::br() . EEH_HTML::div('', '', 'admin-primary-mbox-tbl-wrap');
+        $registrations_to_apply_payment_to .= EEH_HTML::br().EEH_HTML::div('', '', 'admin-primary-mbox-tbl-wrap');
         $registrations_to_apply_payment_to .= EEH_HTML::table('', '', 'admin-primary-mbox-tbl');
         $registrations_to_apply_payment_to .= EEH_HTML::thead(
             EEH_HTML::tr(
-                EEH_HTML::th(esc_html__('ID', 'event_espresso')) .
-                EEH_HTML::th(esc_html__('Registrant', 'event_espresso')) .
-                EEH_HTML::th(esc_html__('Ticket', 'event_espresso')) .
-                EEH_HTML::th(esc_html__('Event', 'event_espresso')) .
-                EEH_HTML::th(esc_html__('Paid', 'event_espresso'), '', 'txn-admin-payment-paid-td jst-cntr') .
-                EEH_HTML::th(esc_html__('Owing', 'event_espresso'), '', 'txn-admin-payment-owing-td jst-cntr') .
+                EEH_HTML::th(esc_html__('ID', 'event_espresso')).
+                EEH_HTML::th(esc_html__('Registrant', 'event_espresso')).
+                EEH_HTML::th(esc_html__('Ticket', 'event_espresso')).
+                EEH_HTML::th(esc_html__('Event', 'event_espresso')).
+                EEH_HTML::th(esc_html__('Paid', 'event_espresso'), '', 'txn-admin-payment-paid-td jst-cntr').
+                EEH_HTML::th(esc_html__('Owing', 'event_espresso'), '', 'txn-admin-payment-owing-td jst-cntr').
                 EEH_HTML::th(esc_html__('Apply', 'event_espresso'), '', 'jst-cntr')
             )
         );
@@ -1284,7 +1284,7 @@ 
                     : esc_html__('Unknown Attendee', 'event_espresso');
                 $owing = $registration->final_price() - $registration->paid();
                 $taxable = $registration->ticket()->taxable()
-                    ? ' <span class="smaller-text lt-grey-text"> ' . esc_html__('+ tax', 'event_espresso') . '</span>'
+                    ? ' <span class="smaller-text lt-grey-text"> '.esc_html__('+ tax', 'event_espresso').'</span>'
                     : '';
                 $checked = empty($existing_reg_payments)
                            || in_array($registration->ID(), $existing_reg_payments, true)
@@ -1292,26 +1292,26 @@ 
                     : '';
                 $disabled = $registration->final_price() > 0 ? '' : ' disabled';
                 $registrations_to_apply_payment_to .= EEH_HTML::tr(
-                    EEH_HTML::td($registration->ID()) .
-                    EEH_HTML::td($attendee_name) .
+                    EEH_HTML::td($registration->ID()).
+                    EEH_HTML::td($attendee_name).
                     EEH_HTML::td(
-                        $registration->ticket()->name() . ' : ' . $registration->ticket()->pretty_price() . $taxable
-                    ) .
-                    EEH_HTML::td($registration->event_name()) .
-                    EEH_HTML::td($registration->pretty_paid(), '', 'txn-admin-payment-paid-td jst-cntr') .
+                        $registration->ticket()->name().' : '.$registration->ticket()->pretty_price().$taxable
+                    ).
+                    EEH_HTML::td($registration->event_name()).
+                    EEH_HTML::td($registration->pretty_paid(), '', 'txn-admin-payment-paid-td jst-cntr').
                     EEH_HTML::td(
                         EEH_Template::format_currency($owing),
                         '',
                         'txn-admin-payment-owing-td jst-cntr'
-                    ) .
+                    ).
                     EEH_HTML::td(
-                        '<input type="checkbox" value="' . $registration->ID()
+                        '<input type="checkbox" value="'.$registration->ID()
                         . '" name="txn_admin_payment[registrations]"'
-                        . $checked . $disabled . '>',
+                        . $checked.$disabled.'>',
                         '',
                         'jst-cntr'
                     ),
-                    'apply-payment-registration-row-' . $registration->ID()
+                    'apply-payment-registration-row-'.$registration->ID()
                 );
             }
         }
@@ -1392,12 +1392,12 @@ 
                 array(
                     'OR*payment_method_for_payment' => array(
                         'PMD_ID'    => array('IN', $payment_methods_of_payments),
-                        'PMD_scope' => array('LIKE', '%' . EEM_Payment_Method::scope_admin . '%'),
+                        'PMD_scope' => array('LIKE', '%'.EEM_Payment_Method::scope_admin.'%'),
                     ),
                 ),
             );
         } else {
-            $query_args = array(array('PMD_scope' => array('LIKE', '%' . EEM_Payment_Method::scope_admin . '%')));
+            $query_args = array(array('PMD_scope' => array('LIKE', '%'.EEM_Payment_Method::scope_admin.'%')));
         }
         $this->_template_args['payment_methods'] = EEM_Payment_Method::instance()->get_all($query_args);
     }
@@ -1430,7 +1430,7 @@ 
             'Line_Item',
             array(array('LIN_type' => 'line-item'))
         );
-        if (! empty($line_items)) {
+        if ( ! empty($line_items)) {
             foreach ($line_items as $item) {
                 if ($item instanceof EE_Line_Item) {
                     switch ($item->OBJ_type()) {
@@ -1440,7 +1440,7 @@ 
                             $ticket = $item->ticket();
                             // right now we're only handling tickets here.
                             // Cause its expected that only tickets will have attendees right?
-                            if (! $ticket instanceof EE_Ticket) {
+                            if ( ! $ticket instanceof EE_Ticket) {
                                 break;
                             }
                             try {
@@ -1449,45 +1449,45 @@ 
                                 EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
                                 $event_name = esc_html__('Unknown Event', 'event_espresso');
                             }
-                            $event_name .= ' - ' . $item->name();
+                            $event_name .= ' - '.$item->name();
                             $ticket_price = EEH_Template::format_currency($item->unit_price());
                             // now get all of the registrations for this transaction that use this ticket
                             $registrations = $ticket->registrations(
                                 array(array('TXN_ID' => $this->_transaction->ID()))
                             );
                             foreach ($registrations as $registration) {
-                                if (! $registration instanceof EE_Registration) {
+                                if ( ! $registration instanceof EE_Registration) {
                                     break;
                                 }
-                                $this->_template_args['event_attendees'][ $registration->ID() ]['STS_ID']
+                                $this->_template_args['event_attendees'][$registration->ID()]['STS_ID']
                                     = $registration->status_ID();
-                                $this->_template_args['event_attendees'][ $registration->ID() ]['att_num']
+                                $this->_template_args['event_attendees'][$registration->ID()]['att_num']
                                     = $registration->count();
-                                $this->_template_args['event_attendees'][ $registration->ID() ]['event_ticket_name']
+                                $this->_template_args['event_attendees'][$registration->ID()]['event_ticket_name']
                                     = $event_name;
-                                $this->_template_args['event_attendees'][ $registration->ID() ]['ticket_price']
+                                $this->_template_args['event_attendees'][$registration->ID()]['ticket_price']
                                     = $ticket_price;
                                 // attendee info
                                 $attendee = $registration->get_first_related('Attendee');
                                 if ($attendee instanceof EE_Attendee) {
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['att_id']
+                                    $this->_template_args['event_attendees'][$registration->ID()]['att_id']
                                         = $attendee->ID();
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['attendee']
+                                    $this->_template_args['event_attendees'][$registration->ID()]['attendee']
                                         = $attendee->full_name();
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['email']
-                                        = '<a href="mailto:' . $attendee->email() . '?subject=' . $event_name
+                                    $this->_template_args['event_attendees'][$registration->ID()]['email']
+                                        = '<a href="mailto:'.$attendee->email().'?subject='.$event_name
                                           . esc_html__(
                                               ' Event',
                                               'event_espresso'
                                           )
-                                          . '">' . $attendee->email() . '</a>';
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['address']
+                                          . '">'.$attendee->email().'</a>';
+                                    $this->_template_args['event_attendees'][$registration->ID()]['address']
                                         = EEH_Address::format($attendee, 'inline', false, false);
                                 } else {
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['att_id'] = '';
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['attendee'] = '';
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['email'] = '';
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['address'] = '';
+                                    $this->_template_args['event_attendees'][$registration->ID()]['att_id'] = '';
+                                    $this->_template_args['event_attendees'][$registration->ID()]['attendee'] = '';
+                                    $this->_template_args['event_attendees'][$registration->ID()]['email'] = '';
+                                    $this->_template_args['event_attendees'][$registration->ID()]['address'] = '';
                                 }
                             }
                             break;
@@ -1503,7 +1503,7 @@ 
                 TXN_ADMIN_URL
             );
             echo EEH_Template::display_template(
-                TXN_TEMPLATE_PATH . 'txn_admin_details_main_meta_box_attendees.template.php',
+                TXN_TEMPLATE_PATH.'txn_admin_details_main_meta_box_attendees.template.php',
                 $this->_template_args,
                 true
             );
@@ -1538,7 +1538,7 @@ 
         $primary_att = $this->_transaction->primary_registration() instanceof EE_Registration
             ? $this->_transaction->primary_registration()->get_first_related('Attendee')
             : null;
-        if (! $primary_att instanceof EE_Attendee) {
+        if ( ! $primary_att instanceof EE_Attendee) {
             $this->_template_args['no_attendee_message'] = esc_html__(
                 'There is no attached contact for this transaction.  The transaction either failed due to an error or was abandoned.',
                 'event_espresso'
@@ -1560,7 +1560,7 @@ 
         // get formatted address for registrant
         $this->_template_args['formatted_address'] = EEH_Address::format($primary_att);
         echo EEH_Template::display_template(
-            TXN_TEMPLATE_PATH . 'txn_admin_details_side_meta_box_registrant.template.php',
+            TXN_TEMPLATE_PATH.'txn_admin_details_side_meta_box_registrant.template.php',
             $this->_template_args,
             true
         );
@@ -1585,7 +1585,7 @@ 
             TXN_ADMIN_URL
         );
 
-        $template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_side_meta_box_billing_info.template.php';
+        $template_path = TXN_TEMPLATE_PATH.'txn_admin_details_side_meta_box_billing_info.template.php';
         echo EEH_Template::display_template($template_path, $this->_template_args, true);
     }
 
@@ -1611,7 +1611,7 @@ 
             'ee_edit_payments',
             'apply_payment_or_refund_from_registration_details'
         );
-        if (! empty($valid_data) && $has_access) {
+        if ( ! empty($valid_data) && $has_access) {
             $PAY_ID = $valid_data['PAY_ID'];
             // save  the new payment
             $payment = $this->_create_payment_from_request_data($valid_data);
@@ -1624,7 +1624,7 @@ 
                 $REG_IDs = $this->_get_REG_IDs_to_apply_payment_to($payment);
                 $this->_remove_existing_registration_payments($payment, $PAY_ID);
                 // apply payment to registrations (if applicable)
-                if (! empty($REG_IDs)) {
+                if ( ! empty($REG_IDs)) {
                     $this->_update_registration_payments($transaction, $payment, $REG_IDs);
                     $this->_maybe_send_notifications();
                     // now process status changes for the same registrations
@@ -1695,14 +1695,14 @@ 
      */
     protected function _validate_payment_request_data()
     {
-        if (! isset($this->_req_data['txn_admin_payment'])) {
+        if ( ! isset($this->_req_data['txn_admin_payment'])) {
             return array();
         }
         $payment_form = $this->_generate_payment_form_section();
         try {
             if ($payment_form->was_submitted()) {
                 $payment_form->receive_form_submission();
-                if (! $payment_form->is_valid()) {
+                if ( ! $payment_form->is_valid()) {
                     $submission_error_messages = array();
                     foreach ($payment_form->get_validation_errors_accumulated() as $validation_error) {
                         if ($validation_error instanceof EE_Validation_Error) {
@@ -1883,7 +1883,7 @@ 
             array('Y-m-d', 'g:i a')
         );
 
-        if (! $payment->save()) {
+        if ( ! $payment->save()) {
             EE_Error::add_error(
                 sprintf(
                     esc_html__('Payment %1$d has not been successfully saved to the database.', 'event_espresso'),
@@ -2088,12 +2088,12 @@ 
         // but add in some conditions regarding payment,
         // so that we don't apply payments to registrations that are free or have already been paid for
         // but ONLY if the payment is NOT a refund ( ie: the payment amount is not negative )
-        if (! $payment->is_a_refund()) {
+        if ( ! $payment->is_a_refund()) {
             $registration_query_where_params['REG_final_price'] = array('!=', 0);
             $registration_query_where_params['REG_final_price*'] = array('!=', 'REG_paid', true);
         }
         $registrations = $transaction->registrations(array($registration_query_where_params));
-        if (! empty($registrations)) {
+        if ( ! empty($registrations)) {
             /** @type EE_Payment_Processor $payment_processor */
             $payment_processor = EE_Registry::instance()->load_core('Payment_Processor');
             $payment_processor->process_registration_payments($transaction, $payment, $registrations);
@@ -2118,7 +2118,7 @@ 
     protected function _process_registration_status_change(EE_Transaction $transaction, $REG_IDs = array())
     {
         // first if there is no change in status then we get out.
-        if (! isset($this->_req_data['txn_reg_status_change']['reg_status'])
+        if ( ! isset($this->_req_data['txn_reg_status_change']['reg_status'])
             || $this->_req_data['txn_reg_status_change']['reg_status'] === 'NAN'
         ) {
             // no error message, no change requested, just nothing to do man.
@@ -2176,7 +2176,7 @@ 
                 'pay_status'       => $payment->STS_ID(),
                 'PAY_ID'           => $payment->ID(),
                 'STS_ID'           => $payment->STS_ID(),
-                'status'           => self::$_pay_status[ $payment->STS_ID() ],
+                'status'           => self::$_pay_status[$payment->STS_ID()],
                 'date'             => $payment->timestamp('Y-m-d', 'h:i a'),
                 'method'           => strtoupper($payment->source()),
                 'PM_ID'            => $payment->payment_method() ? $payment->payment_method()->ID() : 1,
@@ -2296,11 +2296,11 @@ 
     {
         $registration_payment_data = array();
         // if non empty reg_ids lets get an array of registrations and update the values for the apply_payment/refund rows.
-        if (! empty($REG_IDs)) {
+        if ( ! empty($REG_IDs)) {
             $registrations = EEM_Registration::instance()->get_all(array(array('REG_ID' => array('IN', $REG_IDs))));
             foreach ($registrations as $registration) {
                 if ($registration instanceof EE_Registration) {
-                    $registration_payment_data[ $registration->ID() ] = array(
+                    $registration_payment_data[$registration->ID()] = array(
                         'paid'  => $registration->pretty_paid(),
                         'owing' => EEH_Template::format_currency($registration->final_price() - $registration->paid()),
                     );
@@ -2412,8 +2412,8 @@ 
             : date('m/d/Y');
 
         // make sure our timestamps start and end right at the boundaries for each day
-        $start_date = date('Y-m-d', strtotime($start_date)) . ' 00:00:00';
-        $end_date = date('Y-m-d', strtotime($end_date)) . ' 23:59:59';
+        $start_date = date('Y-m-d', strtotime($start_date)).' 00:00:00';
+        $end_date = date('Y-m-d', strtotime($end_date)).' 23:59:59';
 
 
         // convert to timestamps
@@ -2472,7 +2472,7 @@ 
         }
 
         if (isset($this->_req_data['s'])) {
-            $search_string = '%' . $this->_req_data['s'] . '%';
+            $search_string = '%'.$this->_req_data['s'].'%';
             $_where['OR'] = array(
                 'Registration.Event.EVT_name'         => array('LIKE', $search_string),
                 'Registration.Event.EVT_desc'         => array('LIKE', $search_string),
@@ -2499,11 +2499,11 @@ 
         }
 
         // failed transactions
-        $failed = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'failed' && ! $count)
+        $failed = ( ! empty($this->_req_data['status']) && $this->_req_data['status'] === 'failed' && ! $count)
                   || ($count && $view === 'failed');
-        $abandoned = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'abandoned' && ! $count)
+        $abandoned = ( ! empty($this->_req_data['status']) && $this->_req_data['status'] === 'abandoned' && ! $count)
                      || ($count && $view === 'abandoned');
-        $incomplete = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'incomplete' && ! $count)
+        $incomplete = ( ! empty($this->_req_data['status']) && $this->_req_data['status'] === 'incomplete' && ! $count)
                       || ($count && $view === 'incomplete');
 
         if ($failed) {

Indentation +2558 added lines, -2558 removed lines

@@ -13,2562 +13,2562 @@
 class Transactions_Admin_Page extends EE_Admin_Page
 {
 
-    /**
-     * @var EE_Transaction
-     */
-    private $_transaction;
-
-    /**
-     * @var EE_Session
-     */
-    private $_session;
-
-    /**
-     * @var array $_txn_status
-     */
-    private static $_txn_status;
-
-    /**
-     * @var array $_pay_status
-     */
-    private static $_pay_status;
-
-    /**
-     * @var array $_existing_reg_payment_REG_IDs
-     */
-    protected $_existing_reg_payment_REG_IDs;
-
-
-    /**
-     *    _init_page_props
-     *
-     * @return void
-     */
-    protected function _init_page_props()
-    {
-        $this->page_slug = TXN_PG_SLUG;
-        $this->page_label = esc_html__('Transactions', 'event_espresso');
-        $this->_admin_base_url = TXN_ADMIN_URL;
-        $this->_admin_base_path = TXN_ADMIN;
-    }
-
-
-    /**
-     *    _ajax_hooks
-     *
-     * @return void
-     */
-    protected function _ajax_hooks()
-    {
-        add_action('wp_ajax_espresso_apply_payment', array($this, 'apply_payments_or_refunds'));
-        add_action('wp_ajax_espresso_apply_refund', array($this, 'apply_payments_or_refunds'));
-        add_action('wp_ajax_espresso_delete_payment', array($this, 'delete_payment'));
-    }
-
-
-    /**
-     *    _define_page_props
-     *
-     * @return void
-     */
-    protected function _define_page_props()
-    {
-        $this->_admin_page_title = $this->page_label;
-        $this->_labels = array(
-            'buttons' => array(
-                'add'    => esc_html__('Add New Transaction', 'event_espresso'),
-                'edit'   => esc_html__('Edit Transaction', 'event_espresso'),
-                'delete' => esc_html__('Delete Transaction', 'event_espresso'),
-            ),
-        );
-    }
-
-
-    /**
-     *        grab url requests and route them
-     *
-     * @access private
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function _set_page_routes()
-    {
-
-        $this->_set_transaction_status_array();
-
-        $txn_id = ! empty($this->_req_data['TXN_ID'])
-                  && ! is_array($this->_req_data['TXN_ID'])
-            ? $this->_req_data['TXN_ID']
-            : 0;
-
-        $this->_page_routes = array(
-
-            'default' => array(
-                'func'       => '_transactions_overview_list_table',
-                'capability' => 'ee_read_transactions',
-            ),
-
-            'view_transaction' => array(
-                'func'       => '_transaction_details',
-                'capability' => 'ee_read_transaction',
-                'obj_id'     => $txn_id,
-            ),
-
-            'send_payment_reminder' => array(
-                'func'       => '_send_payment_reminder',
-                'noheader'   => true,
-                'capability' => 'ee_send_message',
-            ),
-
-            'espresso_apply_payment' => array(
-                'func'       => 'apply_payments_or_refunds',
-                'noheader'   => true,
-                'capability' => 'ee_edit_payments',
-            ),
-
-            'espresso_apply_refund' => array(
-                'func'       => 'apply_payments_or_refunds',
-                'noheader'   => true,
-                'capability' => 'ee_edit_payments',
-            ),
-
-            'espresso_delete_payment' => array(
-                'func'       => 'delete_payment',
-                'noheader'   => true,
-                'capability' => 'ee_delete_payments',
-            ),
-
-            'espresso_recalculate_line_items' => array(
-                'func'       => 'recalculateLineItems',
-                'noheader'   => true,
-                'capability' => 'ee_edit_payments',
-            ),
-
-        );
-    }
-
-
-    protected function _set_page_config()
-    {
-        $this->_page_config = array(
-            'default'          => array(
-                'nav'           => array(
-                    'label' => esc_html__('Overview', 'event_espresso'),
-                    'order' => 10,
-                ),
-                'list_table'    => 'EE_Admin_Transactions_List_Table',
-                'help_tabs'     => array(
-                    'transactions_overview_help_tab'                       => array(
-                        'title'    => esc_html__('Transactions Overview', 'event_espresso'),
-                        'filename' => 'transactions_overview',
-                    ),
-                    'transactions_overview_table_column_headings_help_tab' => array(
-                        'title'    => esc_html__('Transactions Table Column Headings', 'event_espresso'),
-                        'filename' => 'transactions_overview_table_column_headings',
-                    ),
-                    'transactions_overview_views_filters_help_tab'         => array(
-                        'title'    => esc_html__('Transaction Views & Filters & Search', 'event_espresso'),
-                        'filename' => 'transactions_overview_views_filters_search',
-                    ),
-                ),
-                'help_tour'     => array('Transactions_Overview_Help_Tour'),
-                /**
-                 * commented out because currently we are not displaying tips for transaction list table status but this
-                 * may change in a later iteration so want to keep the code for then.
-                 */
-                // 'qtips' => array( 'Transactions_List_Table_Tips' ),
-                'require_nonce' => false,
-            ),
-            'view_transaction' => array(
-                'nav'       => array(
-                    'label'      => esc_html__('View Transaction', 'event_espresso'),
-                    'order'      => 5,
-                    'url'        => isset($this->_req_data['TXN_ID'])
-                        ? add_query_arg(array('TXN_ID' => $this->_req_data['TXN_ID']), $this->_current_page_view_url)
-                        : $this->_admin_base_url,
-                    'persistent' => false,
-                ),
-                'help_tabs' => array(
-                    'transactions_view_transaction_help_tab'                                              => array(
-                        'title'    => esc_html__('View Transaction', 'event_espresso'),
-                        'filename' => 'transactions_view_transaction',
-                    ),
-                    'transactions_view_transaction_transaction_details_table_help_tab'                    => array(
-                        'title'    => esc_html__('Transaction Details Table', 'event_espresso'),
-                        'filename' => 'transactions_view_transaction_transaction_details_table',
-                    ),
-                    'transactions_view_transaction_attendees_registered_help_tab'                         => array(
-                        'title'    => esc_html__('Attendees Registered', 'event_espresso'),
-                        'filename' => 'transactions_view_transaction_attendees_registered',
-                    ),
-                    'transactions_view_transaction_views_primary_registrant_billing_information_help_tab' => array(
-                        'title'    => esc_html__('Primary Registrant & Billing Information', 'event_espresso'),
-                        'filename' => 'transactions_view_transaction_primary_registrant_billing_information',
-                    ),
-                ),
-                'qtips'     => array('Transaction_Details_Tips'),
-                'help_tour' => array('Transaction_Details_Help_Tour'),
-                'metaboxes' => array('_transaction_details_metaboxes'),
-
-                'require_nonce' => false,
-            ),
-        );
-    }
-
-
-    /**
-     * The below methods aren't used by this class currently
-     */
-    protected function _add_screen_options()
-    {
-        // noop
-    }
-
-
-    protected function _add_feature_pointers()
-    {
-        // noop
-    }
-
-
-    public function admin_init()
-    {
-        // IF a registration was JUST added via the admin...
-        if (isset(
-            $this->_req_data['redirect_from'],
-            $this->_req_data['EVT_ID'],
-            $this->_req_data['event_name']
-        )) {
-            // then set a cookie so that we can block any attempts to use
-            // the back button as a way to enter another registration.
-            setcookie(
-                'ee_registration_added',
-                $this->_req_data['EVT_ID'],
-                time() + WEEK_IN_SECONDS,
-                '/'
-            );
-            // and update the global
-            $_COOKIE['ee_registration_added'] = $this->_req_data['EVT_ID'];
-        }
-        EE_Registry::$i18n_js_strings['invalid_server_response'] = esc_html__(
-            'An error occurred! Your request may have been processed, but a valid response from the server was not received. Please refresh the page and try again.',
-            'event_espresso'
-        );
-        EE_Registry::$i18n_js_strings['error_occurred'] = esc_html__(
-            'An error occurred! Please refresh the page and try again.',
-            'event_espresso'
-        );
-        EE_Registry::$i18n_js_strings['txn_status_array'] = self::$_txn_status;
-        EE_Registry::$i18n_js_strings['pay_status_array'] = self::$_pay_status;
-        EE_Registry::$i18n_js_strings['payments_total'] = esc_html__('Payments Total', 'event_espresso');
-        EE_Registry::$i18n_js_strings['transaction_overpaid'] = esc_html__(
-            'This transaction has been overpaid ! Payments Total',
-            'event_espresso'
-        );
-    }
-
-
-    public function admin_notices()
-    {
-        // noop
-    }
-
-
-    public function admin_footer_scripts()
-    {
-        // noop
-    }
-
-
-    /**
-     * _set_transaction_status_array
-     * sets list of transaction statuses
-     *
-     * @access private
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    private function _set_transaction_status_array()
-    {
-        self::$_txn_status = EEM_Transaction::instance()->status_array(true);
-    }
-
-
-    /**
-     * get_transaction_status_array
-     * return the transaction status array for wp_list_table
-     *
-     * @access public
-     * @return array
-     */
-    public function get_transaction_status_array()
-    {
-        return self::$_txn_status;
-    }
-
-
-    /**
-     *    get list of payment statuses
-     *
-     * @access private
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    private function _get_payment_status_array()
-    {
-        self::$_pay_status = EEM_Payment::instance()->status_array(true);
-        $this->_template_args['payment_status'] = self::$_pay_status;
-    }
-
-
-    /**
-     *    _add_screen_options_default
-     *
-     * @access protected
-     * @return void
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _add_screen_options_default()
-    {
-        $this->_per_page_screen_option();
-    }
-
-
-    /**
-     * load_scripts_styles
-     *
-     * @access public
-     * @return void
-     */
-    public function load_scripts_styles()
-    {
-        // enqueue style
-        wp_register_style(
-            'espresso_txn',
-            TXN_ASSETS_URL . 'espresso_transactions_admin.css',
-            array(),
-            EVENT_ESPRESSO_VERSION
-        );
-        wp_enqueue_style('espresso_txn');
-        // scripts
-        wp_register_script(
-            'espresso_txn',
-            TXN_ASSETS_URL . 'espresso_transactions_admin.js',
-            array(
-                'ee_admin_js',
-                'ee-datepicker',
-                'jquery-ui-datepicker',
-                'jquery-ui-draggable',
-                'ee-dialog',
-                'ee-accounting',
-                'ee-serialize-full-array',
-            ),
-            EVENT_ESPRESSO_VERSION,
-            true
-        );
-        wp_enqueue_script('espresso_txn');
-    }
-
-
-    /**
-     *    load_scripts_styles_view_transaction
-     *
-     * @access public
-     * @return void
-     */
-    public function load_scripts_styles_view_transaction()
-    {
-        // styles
-        wp_enqueue_style('espresso-ui-theme');
-    }
-
-
-    /**
-     *    load_scripts_styles_default
-     *
-     * @access public
-     * @return void
-     */
-    public function load_scripts_styles_default()
-    {
-        // styles
-        wp_enqueue_style('espresso-ui-theme');
-    }
-
-
-    /**
-     *    _set_list_table_views_default
-     *
-     * @access protected
-     * @return void
-     */
-    protected function _set_list_table_views_default()
-    {
-        $this->_views = array(
-            'all'        => array(
-                'slug'  => 'all',
-                'label' => esc_html__('View All Transactions', 'event_espresso'),
-                'count' => 0,
-            ),
-            'abandoned'  => array(
-                'slug'  => 'abandoned',
-                'label' => esc_html__('Abandoned Transactions', 'event_espresso'),
-                'count' => 0,
-            ),
-            'incomplete' => array(
-                'slug'  => 'incomplete',
-                'label' => esc_html__('Incomplete Transactions', 'event_espresso'),
-                'count' => 0,
-            ),
-        );
-        if (/**
-         * Filters whether a link to the "Failed Transactions" list table
-         * appears on the Transactions Admin Page list table.
-         * List display can be turned back on via the following:
-         * add_filter(
-         *     'FHEE__Transactions_Admin_Page___set_list_table_views_default__display_failed_txns_list',
-         *     '__return_true'
-         * );
-         *
-         * @since 4.9.70.p
-         * @param boolean                 $display_failed_txns_list
-         * @param Transactions_Admin_Page $this
-         */
-        apply_filters(
-            'FHEE__Transactions_Admin_Page___set_list_table_views_default__display_failed_txns_list',
-            false,
-            $this
-        )
-        ) {
-            $this->_views['failed'] = array(
-                'slug'  => 'failed',
-                'label' => esc_html__('Failed Transactions', 'event_espresso'),
-                'count' => 0,
-            );
-        }
-    }
-
-
-    /**
-     * _set_transaction_object
-     * This sets the _transaction property for the transaction details screen
-     *
-     * @access private
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws RuntimeException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    private function _set_transaction_object()
-    {
-        if ($this->_transaction instanceof EE_Transaction) {
-            return;
-        } //get out we've already set the object
-
-        $TXN_ID = ! empty($this->_req_data['TXN_ID'])
-            ? absint($this->_req_data['TXN_ID'])
-            : false;
-
-        // get transaction object
-        $this->_transaction = EEM_Transaction::instance()->get_one_by_ID($TXN_ID);
-        $this->_session = $this->_transaction instanceof EE_Transaction
-            ? $this->_transaction->session_data()
-            : null;
-        if ($this->_transaction instanceof EE_Transaction) {
-            $this->_transaction->verify_abandoned_transaction_status();
-        }
-
-        if (! $this->_transaction instanceof EE_Transaction) {
-            $error_msg = sprintf(
-                esc_html__(
-                    'An error occurred and the details for the transaction with the ID # %d could not be retrieved.',
-                    'event_espresso'
-                ),
-                $TXN_ID
-            );
-            EE_Error::add_error($error_msg, __FILE__, __FUNCTION__, __LINE__);
-        }
-    }
-
-
-    /**
-     *    _transaction_legend_items
-     *
-     * @access protected
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _transaction_legend_items()
-    {
-        EE_Registry::instance()->load_helper('MSG_Template');
-        $items = array();
-
-        if (EE_Registry::instance()->CAP->current_user_can(
-            'ee_read_global_messages',
-            'view_filtered_messages'
-        )) {
-            $related_for_icon = EEH_MSG_Template::get_message_action_icon('see_notifications_for');
-            if (is_array($related_for_icon)
-                && isset($related_for_icon['css_class'], $related_for_icon['label'])
-            ) {
-                $items['view_related_messages'] = array(
-                    'class' => $related_for_icon['css_class'],
-                    'desc'  => $related_for_icon['label'],
-                );
-            }
-        }
-
-        $items = apply_filters(
-            'FHEE__Transactions_Admin_Page___transaction_legend_items__items',
-            array_merge(
-                $items,
-                array(
-                    'view_details'          => array(
-                        'class' => 'dashicons dashicons-cart',
-                        'desc'  => esc_html__('View Transaction Details', 'event_espresso'),
-                    ),
-                    'view_invoice'          => array(
-                        'class' => 'dashicons dashicons-media-spreadsheet',
-                        'desc'  => esc_html__('View Transaction Invoice', 'event_espresso'),
-                    ),
-                    'view_receipt'          => array(
-                        'class' => 'dashicons dashicons-media-default',
-                        'desc'  => esc_html__('View Transaction Receipt', 'event_espresso'),
-                    ),
-                    'view_registration'     => array(
-                        'class' => 'dashicons dashicons-clipboard',
-                        'desc'  => esc_html__('View Registration Details', 'event_espresso'),
-                    ),
-                    'payment_overview_link' => array(
-                        'class' => 'dashicons dashicons-money',
-                        'desc'  => esc_html__('Make Payment on Frontend', 'event_espresso'),
-                    ),
-                )
-            )
-        );
-
-        if (EEH_MSG_Template::is_mt_active('payment_reminder')
-            && EE_Registry::instance()->CAP->current_user_can(
-                'ee_send_message',
-                'espresso_transactions_send_payment_reminder'
-            )
-        ) {
-            $items['send_payment_reminder'] = array(
-                'class' => 'dashicons dashicons-email-alt',
-                'desc'  => esc_html__('Send Payment Reminder', 'event_espresso'),
-            );
-        } else {
-            $items['blank*'] = array(
-                'class' => '',
-                'desc'  => '',
-            );
-        }
-        $more_items = apply_filters(
-            'FHEE__Transactions_Admin_Page___transaction_legend_items__more_items',
-            array(
-                'overpaid'   => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::overpaid_status_code,
-                    'desc'  => EEH_Template::pretty_status(
-                        EEM_Transaction::overpaid_status_code,
-                        false,
-                        'sentence'
-                    ),
-                ),
-                'complete'   => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::complete_status_code,
-                    'desc'  => EEH_Template::pretty_status(
-                        EEM_Transaction::complete_status_code,
-                        false,
-                        'sentence'
-                    ),
-                ),
-                'incomplete' => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::incomplete_status_code,
-                    'desc'  => EEH_Template::pretty_status(
-                        EEM_Transaction::incomplete_status_code,
-                        false,
-                        'sentence'
-                    ),
-                ),
-                'abandoned'  => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::abandoned_status_code,
-                    'desc'  => EEH_Template::pretty_status(
-                        EEM_Transaction::abandoned_status_code,
-                        false,
-                        'sentence'
-                    ),
-                ),
-                'failed'     => array(
-                    'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::failed_status_code,
-                    'desc'  => EEH_Template::pretty_status(
-                        EEM_Transaction::failed_status_code,
-                        false,
-                        'sentence'
-                    ),
-                ),
-            )
-        );
-
-        return array_merge($items, $more_items);
-    }
-
-
-    /**
-     *    _transactions_overview_list_table
-     *
-     * @access protected
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _transactions_overview_list_table()
-    {
-        $this->_admin_page_title = esc_html__('Transactions', 'event_espresso');
-        $event = isset($this->_req_data['EVT_ID'])
-            ? EEM_Event::instance()->get_one_by_ID($this->_req_data['EVT_ID'])
-            : null;
-        $this->_template_args['admin_page_header'] = $event instanceof EE_Event
-            ? sprintf(
-                esc_html__(
-                    '%sViewing Transactions for the Event: %s%s',
-                    'event_espresso'
-                ),
-                '<h3>',
-                '<a href="'
-                . EE_Admin_Page::add_query_args_and_nonce(
-                    array('action' => 'edit', 'post' => $event->ID()),
-                    EVENTS_ADMIN_URL
-                )
-                . '" title="'
-                . esc_attr__(
-                    'Click to Edit event',
-                    'event_espresso'
-                )
-                . '">' . $event->name() . '</a>',
-                '</h3>'
-            )
-            : '';
-        $this->_template_args['after_list_table'] = $this->_display_legend($this->_transaction_legend_items());
-        $this->display_admin_list_table_page_with_no_sidebar();
-    }
-
-
-    /**
-     *    _transaction_details
-     * generates HTML for the View Transaction Details Admin page
-     *
-     * @access protected
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws RuntimeException
-     * @throws ReflectionException
-     */
-    protected function _transaction_details()
-    {
-        do_action('AHEE__Transactions_Admin_Page__transaction_details__start', $this->_transaction);
-
-        $this->_set_transaction_status_array();
-
-        $this->_template_args = array();
-        $this->_template_args['transactions_page'] = $this->_wp_page_slug;
-
-        $this->_set_transaction_object();
-
-        if (! $this->_transaction instanceof EE_Transaction) {
-            return;
-        }
-        $primary_registration = $this->_transaction->primary_registration();
-        $attendee = $primary_registration instanceof EE_Registration
-            ? $primary_registration->attendee()
-            : null;
-
-        $this->_template_args['txn_nmbr']['value'] = $this->_transaction->ID();
-        $this->_template_args['txn_nmbr']['label'] = esc_html__('Transaction Number', 'event_espresso');
-
-        $this->_template_args['txn_datetime']['value'] = $this->_transaction->get_i18n_datetime('TXN_timestamp');
-        $this->_template_args['txn_datetime']['label'] = esc_html__('Date', 'event_espresso');
-
-        $this->_template_args['txn_status']['value'] = self::$_txn_status[ $this->_transaction->status_ID() ];
-        $this->_template_args['txn_status']['label'] = esc_html__('Transaction Status', 'event_espresso');
-        $this->_template_args['txn_status']['class'] = 'status-' . $this->_transaction->status_ID();
-
-        $this->_template_args['grand_total'] = $this->_transaction->total();
-        $this->_template_args['total_paid'] = $this->_transaction->paid();
-
-        $amount_due = $this->_transaction->total() - $this->_transaction->paid();
-        $this->_template_args['amount_due'] = EEH_Template::format_currency(
-            $amount_due,
-            true
-        );
-        if (EE_Registry::instance()->CFG->currency->sign_b4) {
-            $this->_template_args['amount_due'] = EE_Registry::instance()->CFG->currency->sign
-                                                  . $this->_template_args['amount_due'];
-        } else {
-            $this->_template_args['amount_due'] .= EE_Registry::instance()->CFG->currency->sign;
-        }
-        $this->_template_args['amount_due_class'] = '';
-
-        if ($this->_transaction->paid() === $this->_transaction->total()) {
-            // paid in full
-            $this->_template_args['amount_due'] = false;
-        } elseif ($this->_transaction->paid() > $this->_transaction->total()) {
-            // overpaid
-            $this->_template_args['amount_due_class'] = 'txn-overview-no-payment-spn';
-        } elseif ($this->_transaction->total() > (float) 0) {
-            if ($this->_transaction->paid() > (float) 0) {
-                // monies owing
-                $this->_template_args['amount_due_class'] = 'txn-overview-part-payment-spn';
-            } elseif ($this->_transaction->paid() === (float) 0) {
-                // no payments made yet
-                $this->_template_args['amount_due_class'] = 'txn-overview-no-payment-spn';
-            }
-        } elseif ($this->_transaction->total() === (float) 0) {
-            // free event
-            $this->_template_args['amount_due'] = false;
-        }
-
-        $payment_method = $this->_transaction->payment_method();
-
-        $this->_template_args['method_of_payment_name'] = $payment_method instanceof EE_Payment_Method
-            ? $payment_method->admin_name()
-            : esc_html__('Unknown', 'event_espresso');
-
-        $this->_template_args['currency_sign'] = EE_Registry::instance()->CFG->currency->sign;
-        // link back to overview
-        $this->_template_args['txn_overview_url'] = ! empty($_SERVER['HTTP_REFERER'])
-            ? $_SERVER['HTTP_REFERER']
-            : TXN_ADMIN_URL;
-
-
-        // next link
-        $next_txn = $this->_transaction->next(
-            null,
-            array(array('STS_ID' => array('!=', EEM_Transaction::failed_status_code))),
-            'TXN_ID'
-        );
-        $this->_template_args['next_transaction'] = $next_txn
-            ? $this->_next_link(
-                EE_Admin_Page::add_query_args_and_nonce(
-                    array('action' => 'view_transaction', 'TXN_ID' => $next_txn['TXN_ID']),
-                    TXN_ADMIN_URL
-                ),
-                'dashicons dashicons-arrow-right ee-icon-size-22'
-            )
-            : '';
-        // previous link
-        $previous_txn = $this->_transaction->previous(
-            null,
-            array(array('STS_ID' => array('!=', EEM_Transaction::failed_status_code))),
-            'TXN_ID'
-        );
-        $this->_template_args['previous_transaction'] = $previous_txn
-            ? $this->_previous_link(
-                EE_Admin_Page::add_query_args_and_nonce(
-                    array('action' => 'view_transaction', 'TXN_ID' => $previous_txn['TXN_ID']),
-                    TXN_ADMIN_URL
-                ),
-                'dashicons dashicons-arrow-left ee-icon-size-22'
-            )
-            : '';
-
-        // were we just redirected here after adding a new registration ???
-        if (isset(
-            $this->_req_data['redirect_from'],
-            $this->_req_data['EVT_ID'],
-            $this->_req_data['event_name']
-        )) {
-            if (EE_Registry::instance()->CAP->current_user_can(
-                'ee_edit_registrations',
-                'espresso_registrations_new_registration',
-                $this->_req_data['EVT_ID']
-            )) {
-                $this->_admin_page_title .= '<a id="add-new-registration" class="add-new-h2 button-primary" href="';
-                $this->_admin_page_title .= EE_Admin_Page::add_query_args_and_nonce(
-                    array(
-                        'page'     => 'espresso_registrations',
-                        'action'   => 'new_registration',
-                        'return'   => 'default',
-                        'TXN_ID'   => $this->_transaction->ID(),
-                        'event_id' => $this->_req_data['EVT_ID'],
-                    ),
-                    REG_ADMIN_URL
-                );
-                $this->_admin_page_title .= '">';
-
-                $this->_admin_page_title .= sprintf(
-                    esc_html__('Add Another New Registration to Event: "%1$s" ?', 'event_espresso'),
-                    htmlentities(urldecode($this->_req_data['event_name']), ENT_QUOTES, 'UTF-8')
-                );
-                $this->_admin_page_title .= '</a>';
-            }
-            EE_Registry::instance()->SSN->clear_session(__CLASS__, __FUNCTION__);
-        }
-        // grab messages at the last second
-        $this->_template_args['notices'] = EE_Error::get_notices();
-        // path to template
-        $template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_header.template.php';
-        $this->_template_args['admin_page_header'] = EEH_Template::display_template(
-            $template_path,
-            $this->_template_args,
-            true
-        );
-
-        // the details template wrapper
-        $this->display_admin_page_with_sidebar();
-    }
-
-
-    /**
-     *        _transaction_details_metaboxes
-     *
-     * @access protected
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws RuntimeException
-     * @throws ReflectionException
-     */
-    protected function _transaction_details_metaboxes()
-    {
-
-        $this->_set_transaction_object();
-
-        if (! $this->_transaction instanceof EE_Transaction) {
-            return;
-        }
-        add_meta_box(
-            'edit-txn-details-mbox',
-            esc_html__('Transaction Details', 'event_espresso'),
-            array($this, 'txn_details_meta_box'),
-            $this->_wp_page_slug,
-            'normal',
-            'high'
-        );
-        add_meta_box(
-            'edit-txn-attendees-mbox',
-            esc_html__('Attendees Registered in this Transaction', 'event_espresso'),
-            array($this, 'txn_attendees_meta_box'),
-            $this->_wp_page_slug,
-            'normal',
-            'high',
-            array('TXN_ID' => $this->_transaction->ID())
-        );
-        add_meta_box(
-            'edit-txn-registrant-mbox',
-            esc_html__('Primary Contact', 'event_espresso'),
-            array($this, 'txn_registrant_side_meta_box'),
-            $this->_wp_page_slug,
-            'side',
-            'high'
-        );
-        add_meta_box(
-            'edit-txn-billing-info-mbox',
-            esc_html__('Billing Information', 'event_espresso'),
-            array($this, 'txn_billing_info_side_meta_box'),
-            $this->_wp_page_slug,
-            'side',
-            'high'
-        );
-    }
-
-
-    /**
-     * Callback for transaction actions metabox.
-     *
-     * @param EE_Transaction|null $transaction
-     * @return string
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    public function getActionButtons(EE_Transaction $transaction = null)
-    {
-        $content = '';
-        $actions = array();
-        if (! $transaction instanceof EE_Transaction) {
-            return $content;
-        }
-        /** @var EE_Registration $primary_registration */
-        $primary_registration = $transaction->primary_registration();
-        $attendee = $primary_registration instanceof EE_Registration
-            ? $primary_registration->attendee()
-            : null;
-
-        if ($attendee instanceof EE_Attendee
-            && EE_Registry::instance()->CAP->current_user_can(
-                'ee_send_message',
-                'espresso_transactions_send_payment_reminder'
-            )
-        ) {
-            $actions['payment_reminder'] =
-                EEH_MSG_Template::is_mt_active('payment_reminder')
-                && $this->_transaction->status_ID() !== EEM_Transaction::complete_status_code
-                && $this->_transaction->status_ID() !== EEM_Transaction::overpaid_status_code
-                    ? EEH_Template::get_button_or_link(
-                        EE_Admin_Page::add_query_args_and_nonce(
-                            array(
-                                'action'      => 'send_payment_reminder',
-                                'TXN_ID'      => $this->_transaction->ID(),
-                                'redirect_to' => 'view_transaction',
-                            ),
-                            TXN_ADMIN_URL
-                        ),
-                        esc_html__(' Send Payment Reminder', 'event_espresso'),
-                        'button secondary-button',
-                        'dashicons dashicons-email-alt'
-                    )
-                    : '';
-        }
-
-        if (EE_Registry::instance()->CAP->current_user_can(
-            'ee_edit_payments',
-            'espresso_transactions_recalculate_line_items'
-        )
-        ) {
-            $actions['recalculate_line_items'] = EEH_Template::get_button_or_link(
-                EE_Admin_Page::add_query_args_and_nonce(
-                    array(
-                        'action'      => 'espresso_recalculate_line_items',
-                        'TXN_ID'      => $this->_transaction->ID(),
-                        'redirect_to' => 'view_transaction',
-                    ),
-                    TXN_ADMIN_URL
-                ),
-                esc_html__(' Recalculate Taxes and Total', 'event_espresso'),
-                'button secondary-button',
-                'dashicons dashicons-update'
-            );
-        }
-
-        if ($primary_registration instanceof EE_Registration
-            && EEH_MSG_Template::is_mt_active('receipt')
-        ) {
-            $actions['receipt'] = EEH_Template::get_button_or_link(
-                $primary_registration->receipt_url(),
-                esc_html__('View Receipt', 'event_espresso'),
-                'button secondary-button',
-                'dashicons dashicons-media-default'
-            );
-        }
-
-        if ($primary_registration instanceof EE_Registration
-            && EEH_MSG_Template::is_mt_active('invoice')
-        ) {
-            $actions['invoice'] = EEH_Template::get_button_or_link(
-                $primary_registration->invoice_url(),
-                esc_html__('View Invoice', 'event_espresso'),
-                'button secondary-button',
-                'dashicons dashicons-media-spreadsheet'
-            );
-        }
-        $actions = array_filter(
-            apply_filters('FHEE__Transactions_Admin_Page__getActionButtons__actions', $actions, $transaction)
-        );
-        if ($actions) {
-            $content = '<ul>';
-            $content .= '<li>' . implode('</li><li>', $actions) . '</li>';
-            $content .= '</uL>';
-        }
-        return $content;
-    }
-
-
-    /**
-     * txn_details_meta_box
-     * generates HTML for the Transaction main meta box
-     *
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws RuntimeException
-     * @throws ReflectionException
-     */
-    public function txn_details_meta_box()
-    {
-        $this->_set_transaction_object();
-        $this->_template_args['TXN_ID'] = $this->_transaction->ID();
-        $this->_template_args['attendee'] = $this->_transaction->primary_registration() instanceof EE_Registration
-            ? $this->_transaction->primary_registration()->attendee()
-            : null;
-        $this->_template_args['can_edit_payments'] = EE_Registry::instance()->CAP->current_user_can(
-            'ee_edit_payments',
-            'apply_payment_or_refund_from_registration_details'
-        );
-        $this->_template_args['can_delete_payments'] = EE_Registry::instance()->CAP->current_user_can(
-            'ee_delete_payments',
-            'delete_payment_from_registration_details'
-        );
-
-        // get line table
-        EEH_Autoloader::register_line_item_display_autoloaders();
-        $Line_Item_Display = new EE_Line_Item_Display(
-            'admin_table',
-            'EE_Admin_Table_Line_Item_Display_Strategy'
-        );
-        $this->_template_args['line_item_table'] = $Line_Item_Display->display_line_item(
-            $this->_transaction->total_line_item()
-        );
-        $this->_template_args['REG_code'] = $this->_transaction->primary_registration()->reg_code();
-
-        // process taxes
-        $taxes = $this->_transaction->line_items(array(array('LIN_type' => EEM_Line_Item::type_tax)));
-        $this->_template_args['taxes'] = ! empty($taxes) ? $taxes : false;
-
-        $this->_template_args['grand_total'] = EEH_Template::format_currency(
-            $this->_transaction->total(),
-            false,
-            false
-        );
-        $this->_template_args['grand_raw_total'] = $this->_transaction->total();
-        $this->_template_args['TXN_status'] = $this->_transaction->status_ID();
-
-        // process payment details
-        $payments = $this->_transaction->payments();
-        if (! empty($payments)) {
-            $this->_template_args['payments'] = $payments;
-            $this->_template_args['existing_reg_payments'] = $this->_get_registration_payment_IDs($payments);
-        } else {
-            $this->_template_args['payments'] = false;
-            $this->_template_args['existing_reg_payments'] = array();
-        }
-
-        $this->_template_args['edit_payment_url'] = add_query_arg(array('action' => 'edit_payment'), TXN_ADMIN_URL);
-        $this->_template_args['delete_payment_url'] = add_query_arg(
-            array('action' => 'espresso_delete_payment'),
-            TXN_ADMIN_URL
-        );
-
-        if (isset($txn_details['invoice_number'])) {
-            $this->_template_args['txn_details']['invoice_number']['value'] = $this->_template_args['REG_code'];
-            $this->_template_args['txn_details']['invoice_number']['label'] = esc_html__(
-                'Invoice Number',
-                'event_espresso'
-            );
-        }
-
-        $this->_template_args['txn_details']['registration_session']['value'] = $this->_transaction
-            ->primary_registration()
-            ->session_ID();
-        $this->_template_args['txn_details']['registration_session']['label'] = esc_html__(
-            'Registration Session',
-            'event_espresso'
-        );
-
-        $this->_template_args['txn_details']['ip_address']['value'] = isset($this->_session['ip_address'])
-            ? $this->_session['ip_address']
-            : '';
-        $this->_template_args['txn_details']['ip_address']['label'] = esc_html__(
-            'Transaction placed from IP',
-            'event_espresso'
-        );
-
-        $this->_template_args['txn_details']['user_agent']['value'] = isset($this->_session['user_agent'])
-            ? $this->_session['user_agent']
-            : '';
-        $this->_template_args['txn_details']['user_agent']['label'] = esc_html__(
-            'Registrant User Agent',
-            'event_espresso'
-        );
-
-        $reg_steps = '<ul>';
-        foreach ($this->_transaction->reg_steps() as $reg_step => $reg_step_status) {
-            if ($reg_step_status === true) {
-                $reg_steps .= '<li style="color:#70cc50">'
-                              . sprintf(
-                                  esc_html__('%1$s : Completed', 'event_espresso'),
-                                  ucwords(str_replace('_', ' ', $reg_step))
-                              )
-                              . '</li>';
-            } elseif (is_numeric($reg_step_status) && $reg_step_status !== false) {
-                $reg_steps .= '<li style="color:#2EA2CC">'
-                              . sprintf(
-                                  esc_html__('%1$s : Initiated %2$s', 'event_espresso'),
-                                  ucwords(str_replace('_', ' ', $reg_step)),
-                                  date(
-                                      get_option('date_format') . ' ' . get_option('time_format'),
-                                      $reg_step_status + (get_option('gmt_offset') * HOUR_IN_SECONDS)
-                                  )
-                              )
-                              . '</li>';
-            } else {
-                $reg_steps .= '<li style="color:#E76700">'
-                              . sprintf(
-                                  esc_html__('%1$s : Never Initiated', 'event_espresso'),
-                                  ucwords(str_replace('_', ' ', $reg_step))
-                              )
-                              . '</li>';
-            }
-        }
-        $reg_steps .= '</ul>';
-        $this->_template_args['txn_details']['reg_steps']['value'] = $reg_steps;
-        $this->_template_args['txn_details']['reg_steps']['label'] = esc_html__(
-            'Registration Step Progress',
-            'event_espresso'
-        );
-
-
-        $this->_get_registrations_to_apply_payment_to();
-        $this->_get_payment_methods($payments);
-        $this->_get_payment_status_array();
-        $this->_get_reg_status_selection(); // sets up the template args for the reg status array for the transaction.
-
-        $this->_template_args['transaction_form_url'] = add_query_arg(
-            array(
-                'action'  => 'edit_transaction',
-                'process' => 'transaction',
-            ),
-            TXN_ADMIN_URL
-        );
-        $this->_template_args['apply_payment_form_url'] = add_query_arg(
-            array(
-                'page'   => 'espresso_transactions',
-                'action' => 'espresso_apply_payment',
-            ),
-            WP_AJAX_URL
-        );
-        $this->_template_args['delete_payment_form_url'] = add_query_arg(
-            array(
-                'page'   => 'espresso_transactions',
-                'action' => 'espresso_delete_payment',
-            ),
-            WP_AJAX_URL
-        );
-
-        $this->_template_args['action_buttons'] = $this->getActionButtons($this->_transaction);
-
-        // 'espresso_delete_payment_nonce'
-
-        $template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_main_meta_box_txn_details.template.php';
-        echo EEH_Template::display_template($template_path, $this->_template_args, true);
-    }
-
-
-    /**
-     * _get_registration_payment_IDs
-     *    generates an array of Payment IDs and their corresponding Registration IDs
-     *
-     * @access protected
-     * @param EE_Payment[] $payments
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _get_registration_payment_IDs($payments = array())
-    {
-        $existing_reg_payments = array();
-        // get all reg payments for these payments
-        $reg_payments = EEM_Registration_Payment::instance()->get_all(
-            array(
-                array(
-                    'PAY_ID' => array(
-                        'IN',
-                        array_keys($payments),
-                    ),
-                ),
-            )
-        );
-        if (! empty($reg_payments)) {
-            foreach ($payments as $payment) {
-                if (! $payment instanceof EE_Payment) {
-                    continue;
-                } elseif (! isset($existing_reg_payments[ $payment->ID() ])) {
-                    $existing_reg_payments[ $payment->ID() ] = array();
-                }
-                foreach ($reg_payments as $reg_payment) {
-                    if ($reg_payment instanceof EE_Registration_Payment
-                        && $reg_payment->payment_ID() === $payment->ID()
-                    ) {
-                        $existing_reg_payments[ $payment->ID() ][] = $reg_payment->registration_ID();
-                    }
-                }
-            }
-        }
-
-        return $existing_reg_payments;
-    }
-
-
-    /**
-     * _get_registrations_to_apply_payment_to
-     *    generates HTML for displaying a series of checkboxes in the admin payment modal window
-     * which allows the admin to only apply the payment to the specific registrations
-     *
-     * @access protected
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _get_registrations_to_apply_payment_to()
-    {
-        // we want any registration with an active status (ie: not deleted or cancelled)
-        $query_params = array(
-            array(
-                'STS_ID' => array(
-                    'IN',
-                    array(
-                        EEM_Registration::status_id_approved,
-                        EEM_Registration::status_id_pending_payment,
-                        EEM_Registration::status_id_not_approved,
-                    ),
-                ),
-            ),
-        );
-        $registrations_to_apply_payment_to = EEH_HTML::br() . EEH_HTML::div(
-            '',
-            'txn-admin-apply-payment-to-registrations-dv',
-            '',
-            'clear: both; margin: 1.5em 0 0; display: none;'
-        );
-        $registrations_to_apply_payment_to .= EEH_HTML::br() . EEH_HTML::div('', '', 'admin-primary-mbox-tbl-wrap');
-        $registrations_to_apply_payment_to .= EEH_HTML::table('', '', 'admin-primary-mbox-tbl');
-        $registrations_to_apply_payment_to .= EEH_HTML::thead(
-            EEH_HTML::tr(
-                EEH_HTML::th(esc_html__('ID', 'event_espresso')) .
-                EEH_HTML::th(esc_html__('Registrant', 'event_espresso')) .
-                EEH_HTML::th(esc_html__('Ticket', 'event_espresso')) .
-                EEH_HTML::th(esc_html__('Event', 'event_espresso')) .
-                EEH_HTML::th(esc_html__('Paid', 'event_espresso'), '', 'txn-admin-payment-paid-td jst-cntr') .
-                EEH_HTML::th(esc_html__('Owing', 'event_espresso'), '', 'txn-admin-payment-owing-td jst-cntr') .
-                EEH_HTML::th(esc_html__('Apply', 'event_espresso'), '', 'jst-cntr')
-            )
-        );
-        $registrations_to_apply_payment_to .= EEH_HTML::tbody();
-        // get registrations for TXN
-        $registrations = $this->_transaction->registrations($query_params);
-        $existing_reg_payments = $this->_template_args['existing_reg_payments'];
-        foreach ($registrations as $registration) {
-            if ($registration instanceof EE_Registration) {
-                $attendee_name = $registration->attendee() instanceof EE_Attendee
-                    ? $registration->attendee()->full_name()
-                    : esc_html__('Unknown Attendee', 'event_espresso');
-                $owing = $registration->final_price() - $registration->paid();
-                $taxable = $registration->ticket()->taxable()
-                    ? ' <span class="smaller-text lt-grey-text"> ' . esc_html__('+ tax', 'event_espresso') . '</span>'
-                    : '';
-                $checked = empty($existing_reg_payments)
-                           || in_array($registration->ID(), $existing_reg_payments, true)
-                    ? ' checked="checked"'
-                    : '';
-                $disabled = $registration->final_price() > 0 ? '' : ' disabled';
-                $registrations_to_apply_payment_to .= EEH_HTML::tr(
-                    EEH_HTML::td($registration->ID()) .
-                    EEH_HTML::td($attendee_name) .
-                    EEH_HTML::td(
-                        $registration->ticket()->name() . ' : ' . $registration->ticket()->pretty_price() . $taxable
-                    ) .
-                    EEH_HTML::td($registration->event_name()) .
-                    EEH_HTML::td($registration->pretty_paid(), '', 'txn-admin-payment-paid-td jst-cntr') .
-                    EEH_HTML::td(
-                        EEH_Template::format_currency($owing),
-                        '',
-                        'txn-admin-payment-owing-td jst-cntr'
-                    ) .
-                    EEH_HTML::td(
-                        '<input type="checkbox" value="' . $registration->ID()
-                        . '" name="txn_admin_payment[registrations]"'
-                        . $checked . $disabled . '>',
-                        '',
-                        'jst-cntr'
-                    ),
-                    'apply-payment-registration-row-' . $registration->ID()
-                );
-            }
-        }
-        $registrations_to_apply_payment_to .= EEH_HTML::tbodyx();
-        $registrations_to_apply_payment_to .= EEH_HTML::tablex();
-        $registrations_to_apply_payment_to .= EEH_HTML::divx();
-        $registrations_to_apply_payment_to .= EEH_HTML::p(
-            esc_html__(
-                'The payment will only be applied to the registrations that have a check mark in their corresponding check box. Checkboxes for free registrations have been disabled.',
-                'event_espresso'
-            ),
-            '',
-            'clear description'
-        );
-        $registrations_to_apply_payment_to .= EEH_HTML::divx();
-        $this->_template_args['registrations_to_apply_payment_to'] = $registrations_to_apply_payment_to;
-    }
-
-
-    /**
-     * _get_reg_status_selection
-     *
-     * @todo   this will need to be adjusted either once MER comes along OR we move default reg status to tickets
-     *         instead of events.
-     * @access protected
-     * @return void
-     * @throws EE_Error
-     */
-    protected function _get_reg_status_selection()
-    {
-        // first get all possible statuses
-        $statuses = EEM_Registration::reg_status_array(array(), true);
-        // let's add a "don't change" option.
-        $status_array['NAN'] = esc_html__('Leave the Same', 'event_espresso');
-        $status_array = array_merge($status_array, $statuses);
-        $this->_template_args['status_change_select'] = EEH_Form_Fields::select_input(
-            'txn_reg_status_change[reg_status]',
-            $status_array,
-            'NAN',
-            'id="txn-admin-payment-reg-status-inp"',
-            'txn-reg-status-change-reg-status'
-        );
-        $this->_template_args['delete_status_change_select'] = EEH_Form_Fields::select_input(
-            'delete_txn_reg_status_change[reg_status]',
-            $status_array,
-            'NAN',
-            'delete-txn-admin-payment-reg-status-inp',
-            'delete-txn-reg-status-change-reg-status'
-        );
-    }
-
-
-    /**
-     *    _get_payment_methods
-     * Gets all the payment methods available generally, or the ones that are already
-     * selected on these payments (in case their payment methods are no longer active).
-     * Has the side-effect of updating the template args' payment_methods item
-     *
-     * @access private
-     * @param EE_Payment[] to show on this page
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    private function _get_payment_methods($payments = array())
-    {
-        $payment_methods_of_payments = array();
-        foreach ($payments as $payment) {
-            if ($payment instanceof EE_Payment) {
-                $payment_methods_of_payments[] = $payment->ID();
-            }
-        }
-        if ($payment_methods_of_payments) {
-            $query_args = array(
-                array(
-                    'OR*payment_method_for_payment' => array(
-                        'PMD_ID'    => array('IN', $payment_methods_of_payments),
-                        'PMD_scope' => array('LIKE', '%' . EEM_Payment_Method::scope_admin . '%'),
-                    ),
-                ),
-            );
-        } else {
-            $query_args = array(array('PMD_scope' => array('LIKE', '%' . EEM_Payment_Method::scope_admin . '%')));
-        }
-        $this->_template_args['payment_methods'] = EEM_Payment_Method::instance()->get_all($query_args);
-    }
-
-
-    /**
-     * txn_attendees_meta_box
-     *    generates HTML for the Attendees Transaction main meta box
-     *
-     * @access public
-     * @param WP_Post $post
-     * @param array   $metabox
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function txn_attendees_meta_box($post, $metabox = array('args' => array()))
-    {
-
-        /** @noinspection NonSecureExtractUsageInspection */
-        extract($metabox['args']);
-        $this->_template_args['post'] = $post;
-        $this->_template_args['event_attendees'] = array();
-        // process items in cart
-        $line_items = $this->_transaction->get_many_related(
-            'Line_Item',
-            array(array('LIN_type' => 'line-item'))
-        );
-        if (! empty($line_items)) {
-            foreach ($line_items as $item) {
-                if ($item instanceof EE_Line_Item) {
-                    switch ($item->OBJ_type()) {
-                        case 'Event':
-                            break;
-                        case 'Ticket':
-                            $ticket = $item->ticket();
-                            // right now we're only handling tickets here.
-                            // Cause its expected that only tickets will have attendees right?
-                            if (! $ticket instanceof EE_Ticket) {
-                                break;
-                            }
-                            try {
-                                $event_name = $ticket->get_event_name();
-                            } catch (Exception $e) {
-                                EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
-                                $event_name = esc_html__('Unknown Event', 'event_espresso');
-                            }
-                            $event_name .= ' - ' . $item->name();
-                            $ticket_price = EEH_Template::format_currency($item->unit_price());
-                            // now get all of the registrations for this transaction that use this ticket
-                            $registrations = $ticket->registrations(
-                                array(array('TXN_ID' => $this->_transaction->ID()))
-                            );
-                            foreach ($registrations as $registration) {
-                                if (! $registration instanceof EE_Registration) {
-                                    break;
-                                }
-                                $this->_template_args['event_attendees'][ $registration->ID() ]['STS_ID']
-                                    = $registration->status_ID();
-                                $this->_template_args['event_attendees'][ $registration->ID() ]['att_num']
-                                    = $registration->count();
-                                $this->_template_args['event_attendees'][ $registration->ID() ]['event_ticket_name']
-                                    = $event_name;
-                                $this->_template_args['event_attendees'][ $registration->ID() ]['ticket_price']
-                                    = $ticket_price;
-                                // attendee info
-                                $attendee = $registration->get_first_related('Attendee');
-                                if ($attendee instanceof EE_Attendee) {
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['att_id']
-                                        = $attendee->ID();
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['attendee']
-                                        = $attendee->full_name();
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['email']
-                                        = '<a href="mailto:' . $attendee->email() . '?subject=' . $event_name
-                                          . esc_html__(
-                                              ' Event',
-                                              'event_espresso'
-                                          )
-                                          . '">' . $attendee->email() . '</a>';
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['address']
-                                        = EEH_Address::format($attendee, 'inline', false, false);
-                                } else {
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['att_id'] = '';
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['attendee'] = '';
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['email'] = '';
-                                    $this->_template_args['event_attendees'][ $registration->ID() ]['address'] = '';
-                                }
-                            }
-                            break;
-                    }
-                }
-            }
-
-            $this->_template_args['transaction_form_url'] = add_query_arg(
-                array(
-                    'action'  => 'edit_transaction',
-                    'process' => 'attendees',
-                ),
-                TXN_ADMIN_URL
-            );
-            echo EEH_Template::display_template(
-                TXN_TEMPLATE_PATH . 'txn_admin_details_main_meta_box_attendees.template.php',
-                $this->_template_args,
-                true
-            );
-        } else {
-            echo sprintf(
-                esc_html__(
-                    '%1$sFor some reason, there are no attendees registered for this transaction. Likely the registration was abandoned in process.%2$s',
-                    'event_espresso'
-                ),
-                '<p class="important-notice">',
-                '</p>'
-            );
-        }
-    }
-
-
-    /**
-     * txn_registrant_side_meta_box
-     * generates HTML for the Edit Transaction side meta box
-     *
-     * @access public
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function txn_registrant_side_meta_box()
-    {
-        $primary_att = $this->_transaction->primary_registration() instanceof EE_Registration
-            ? $this->_transaction->primary_registration()->get_first_related('Attendee')
-            : null;
-        if (! $primary_att instanceof EE_Attendee) {
-            $this->_template_args['no_attendee_message'] = esc_html__(
-                'There is no attached contact for this transaction.  The transaction either failed due to an error or was abandoned.',
-                'event_espresso'
-            );
-            $primary_att = EEM_Attendee::instance()->create_default_object();
-        }
-        $this->_template_args['ATT_ID'] = $primary_att->ID();
-        $this->_template_args['prime_reg_fname'] = $primary_att->fname();
-        $this->_template_args['prime_reg_lname'] = $primary_att->lname();
-        $this->_template_args['prime_reg_email'] = $primary_att->email();
-        $this->_template_args['prime_reg_phone'] = $primary_att->phone();
-        $this->_template_args['edit_attendee_url'] = EE_Admin_Page::add_query_args_and_nonce(
-            array(
-                'action' => 'edit_attendee',
-                'post'   => $primary_att->ID(),
-            ),
-            REG_ADMIN_URL
-        );
-        // get formatted address for registrant
-        $this->_template_args['formatted_address'] = EEH_Address::format($primary_att);
-        echo EEH_Template::display_template(
-            TXN_TEMPLATE_PATH . 'txn_admin_details_side_meta_box_registrant.template.php',
-            $this->_template_args,
-            true
-        );
-    }
-
-
-    /**
-     * txn_billing_info_side_meta_box
-     *    generates HTML for the Edit Transaction side meta box
-     *
-     * @access public
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     */
-    public function txn_billing_info_side_meta_box()
-    {
-
-        $this->_template_args['billing_form'] = $this->_transaction->billing_info();
-        $this->_template_args['billing_form_url'] = add_query_arg(
-            array('action' => 'edit_transaction', 'process' => 'billing'),
-            TXN_ADMIN_URL
-        );
-
-        $template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_side_meta_box_billing_info.template.php';
-        echo EEH_Template::display_template($template_path, $this->_template_args, true);
-    }
-
-
-    /**
-     * apply_payments_or_refunds
-     *    registers a payment or refund made towards a transaction
-     *
-     * @access public
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function apply_payments_or_refunds()
-    {
-        $json_response_data = array('return_data' => false);
-        $valid_data = $this->_validate_payment_request_data();
-        $has_access = EE_Registry::instance()->CAP->current_user_can(
-            'ee_edit_payments',
-            'apply_payment_or_refund_from_registration_details'
-        );
-        if (! empty($valid_data) && $has_access) {
-            $PAY_ID = $valid_data['PAY_ID'];
-            // save  the new payment
-            $payment = $this->_create_payment_from_request_data($valid_data);
-            // get the TXN for this payment
-            $transaction = $payment->transaction();
-            // verify transaction
-            if ($transaction instanceof EE_Transaction) {
-                // calculate_total_payments_and_update_status
-                $this->_process_transaction_payments($transaction);
-                $REG_IDs = $this->_get_REG_IDs_to_apply_payment_to($payment);
-                $this->_remove_existing_registration_payments($payment, $PAY_ID);
-                // apply payment to registrations (if applicable)
-                if (! empty($REG_IDs)) {
-                    $this->_update_registration_payments($transaction, $payment, $REG_IDs);
-                    $this->_maybe_send_notifications();
-                    // now process status changes for the same registrations
-                    $this->_process_registration_status_change($transaction, $REG_IDs);
-                }
-                $this->_maybe_send_notifications($payment);
-                // prepare to render page
-                $json_response_data['return_data'] = $this->_build_payment_json_response($payment, $REG_IDs);
-                do_action(
-                    'AHEE__Transactions_Admin_Page__apply_payments_or_refund__after_recording',
-                    $transaction,
-                    $payment
-                );
-            } else {
-                EE_Error::add_error(
-                    esc_html__(
-                        'A valid Transaction for this payment could not be retrieved.',
-                        'event_espresso'
-                    ),
-                    __FILE__,
-                    __FUNCTION__,
-                    __LINE__
-                );
-            }
-        } elseif ($has_access) {
-            EE_Error::add_error(
-                esc_html__(
-                    'The payment form data could not be processed. Please try again.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        } else {
-            EE_Error::add_error(
-                esc_html__(
-                    'You do not have access to apply payments or refunds to a registration.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        }
-        $notices = EE_Error::get_notices(
-            false,
-            false,
-            false
-        );
-        $this->_template_args = array(
-            'data'    => $json_response_data,
-            'error'   => $notices['errors'],
-            'success' => $notices['success'],
-        );
-        $this->_return_json();
-    }
-
-
-    /**
-     * _validate_payment_request_data
-     *
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _validate_payment_request_data()
-    {
-        if (! isset($this->_req_data['txn_admin_payment'])) {
-            return array();
-        }
-        $payment_form = $this->_generate_payment_form_section();
-        try {
-            if ($payment_form->was_submitted()) {
-                $payment_form->receive_form_submission();
-                if (! $payment_form->is_valid()) {
-                    $submission_error_messages = array();
-                    foreach ($payment_form->get_validation_errors_accumulated() as $validation_error) {
-                        if ($validation_error instanceof EE_Validation_Error) {
-                            $submission_error_messages[] = sprintf(
-                                _x('%s : %s', 'Form Section Name : Form Validation Error', 'event_espresso'),
-                                $validation_error->get_form_section()->html_label_text(),
-                                $validation_error->getMessage()
-                            );
-                        }
-                    }
-                    EE_Error::add_error(
-                        implode('<br />', $submission_error_messages),
-                        __FILE__,
-                        __FUNCTION__,
-                        __LINE__
-                    );
-                    return array();
-                }
-            }
-        } catch (EE_Error $e) {
-            EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
-            return array();
-        }
-
-        return $payment_form->valid_data();
-    }
-
-
-    /**
-     * _generate_payment_form_section
-     *
-     * @return EE_Form_Section_Proper
-     * @throws EE_Error
-     */
-    protected function _generate_payment_form_section()
-    {
-        return new EE_Form_Section_Proper(
-            array(
-                'name'        => 'txn_admin_payment',
-                'subsections' => array(
-                    'PAY_ID'          => new EE_Text_Input(
-                        array(
-                            'default'               => 0,
-                            'required'              => false,
-                            'html_label_text'       => esc_html__('Payment ID', 'event_espresso'),
-                            'validation_strategies' => array(new EE_Int_Normalization()),
-                        )
-                    ),
-                    'TXN_ID'          => new EE_Text_Input(
-                        array(
-                            'default'               => 0,
-                            'required'              => true,
-                            'html_label_text'       => esc_html__('Transaction ID', 'event_espresso'),
-                            'validation_strategies' => array(new EE_Int_Normalization()),
-                        )
-                    ),
-                    'type'            => new EE_Text_Input(
-                        array(
-                            'default'               => 1,
-                            'required'              => true,
-                            'html_label_text'       => esc_html__('Payment or Refund', 'event_espresso'),
-                            'validation_strategies' => array(new EE_Int_Normalization()),
-                        )
-                    ),
-                    'amount'          => new EE_Text_Input(
-                        array(
-                            'default'               => 0,
-                            'required'              => true,
-                            'html_label_text'       => esc_html__('Payment amount', 'event_espresso'),
-                            'validation_strategies' => array(new EE_Float_Normalization()),
-                        )
-                    ),
-                    'status'          => new EE_Text_Input(
-                        array(
-                            'default'         => EEM_Payment::status_id_approved,
-                            'required'        => true,
-                            'html_label_text' => esc_html__('Payment status', 'event_espresso'),
-                        )
-                    ),
-                    'PMD_ID'          => new EE_Text_Input(
-                        array(
-                            'default'               => 2,
-                            'required'              => true,
-                            'html_label_text'       => esc_html__('Payment Method', 'event_espresso'),
-                            'validation_strategies' => array(new EE_Int_Normalization()),
-                        )
-                    ),
-                    'date'            => new EE_Text_Input(
-                        array(
-                            'default'         => time(),
-                            'required'        => true,
-                            'html_label_text' => esc_html__('Payment date', 'event_espresso'),
-                        )
-                    ),
-                    'txn_id_chq_nmbr' => new EE_Text_Input(
-                        array(
-                            'default'               => '',
-                            'required'              => false,
-                            'html_label_text'       => esc_html__('Transaction or Cheque Number', 'event_espresso'),
-                            'validation_strategies' => array(
-                                new EE_Max_Length_Validation_Strategy(
-                                    esc_html__('Input too long', 'event_espresso'),
-                                    100
-                                ),
-                            ),
-                        )
-                    ),
-                    'po_number'       => new EE_Text_Input(
-                        array(
-                            'default'               => '',
-                            'required'              => false,
-                            'html_label_text'       => esc_html__('Purchase Order Number', 'event_espresso'),
-                            'validation_strategies' => array(
-                                new EE_Max_Length_Validation_Strategy(
-                                    esc_html__('Input too long', 'event_espresso'),
-                                    100
-                                ),
-                            ),
-                        )
-                    ),
-                    'accounting'      => new EE_Text_Input(
-                        array(
-                            'default'               => '',
-                            'required'              => false,
-                            'html_label_text'       => esc_html__('Extra Field for Accounting', 'event_espresso'),
-                            'validation_strategies' => array(
-                                new EE_Max_Length_Validation_Strategy(
-                                    esc_html__('Input too long', 'event_espresso'),
-                                    100
-                                ),
-                            ),
-                        )
-                    ),
-                ),
-            )
-        );
-    }
-
-
-    /**
-     * _create_payment_from_request_data
-     *
-     * @param array $valid_data
-     * @return EE_Payment
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _create_payment_from_request_data($valid_data)
-    {
-        $PAY_ID = $valid_data['PAY_ID'];
-        // get payment amount
-        $amount = $valid_data['amount'] ? abs($valid_data['amount']) : 0;
-        // payments have a type value of 1 and refunds have a type value of -1
-        // so multiplying amount by type will give a positive value for payments, and negative values for refunds
-        $amount = $valid_data['type'] < 0 ? $amount * -1 : $amount;
-        // for some reason the date string coming in has extra spaces between the date and time.  This fixes that.
-        $date = $valid_data['date']
-            ? preg_replace('/\s+/', ' ', $valid_data['date'])
-            : date('Y-m-d g:i a', current_time('timestamp'));
-        $payment = EE_Payment::new_instance(
-            array(
-                'TXN_ID'              => $valid_data['TXN_ID'],
-                'STS_ID'              => $valid_data['status'],
-                'PAY_timestamp'       => $date,
-                'PAY_source'          => EEM_Payment_Method::scope_admin,
-                'PMD_ID'              => $valid_data['PMD_ID'],
-                'PAY_amount'          => $amount,
-                'PAY_txn_id_chq_nmbr' => $valid_data['txn_id_chq_nmbr'],
-                'PAY_po_number'       => $valid_data['po_number'],
-                'PAY_extra_accntng'   => $valid_data['accounting'],
-                'PAY_details'         => $valid_data,
-                'PAY_ID'              => $PAY_ID,
-            ),
-            '',
-            array('Y-m-d', 'g:i a')
-        );
-
-        if (! $payment->save()) {
-            EE_Error::add_error(
-                sprintf(
-                    esc_html__('Payment %1$d has not been successfully saved to the database.', 'event_espresso'),
-                    $payment->ID()
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        }
-
-        return $payment;
-    }
-
-
-    /**
-     * _process_transaction_payments
-     *
-     * @param \EE_Transaction $transaction
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _process_transaction_payments(EE_Transaction $transaction)
-    {
-        /** @type EE_Transaction_Payments $transaction_payments */
-        $transaction_payments = EE_Registry::instance()->load_class('Transaction_Payments');
-        // update the transaction with this payment
-        if ($transaction_payments->calculate_total_payments_and_update_status($transaction)) {
-            EE_Error::add_success(
-                esc_html__(
-                    'The payment has been processed successfully.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        } else {
-            EE_Error::add_error(
-                esc_html__(
-                    'The payment was processed successfully but the amount paid for the transaction was not updated.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        }
-    }
-
-
-    /**
-     * _get_REG_IDs_to_apply_payment_to
-     * returns a list of registration IDs that the payment will apply to
-     *
-     * @param \EE_Payment $payment
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _get_REG_IDs_to_apply_payment_to(EE_Payment $payment)
-    {
-        $REG_IDs = array();
-        // grab array of IDs for specific registrations to apply changes to
-        if (isset($this->_req_data['txn_admin_payment']['registrations'])) {
-            $REG_IDs = (array) $this->_req_data['txn_admin_payment']['registrations'];
-        }
-        // nothing specified ? then get all reg IDs
-        if (empty($REG_IDs)) {
-            $registrations = $payment->transaction()->registrations();
-            $REG_IDs = ! empty($registrations)
-                ? array_keys($registrations)
-                : $this->_get_existing_reg_payment_REG_IDs($payment);
-        }
-
-        // ensure that REG_IDs are integers and NOT strings
-        return array_map('intval', $REG_IDs);
-    }
-
-
-    /**
-     * @return array
-     */
-    public function existing_reg_payment_REG_IDs()
-    {
-        return $this->_existing_reg_payment_REG_IDs;
-    }
-
-
-    /**
-     * @param array $existing_reg_payment_REG_IDs
-     */
-    public function set_existing_reg_payment_REG_IDs($existing_reg_payment_REG_IDs = null)
-    {
-        $this->_existing_reg_payment_REG_IDs = $existing_reg_payment_REG_IDs;
-    }
-
-
-    /**
-     * _get_existing_reg_payment_REG_IDs
-     * returns a list of registration IDs that the payment is currently related to
-     * as recorded in the database
-     *
-     * @param \EE_Payment $payment
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _get_existing_reg_payment_REG_IDs(EE_Payment $payment)
-    {
-        if ($this->existing_reg_payment_REG_IDs() === null) {
-            // let's get any existing reg payment records for this payment
-            $existing_reg_payment_REG_IDs = $payment->get_many_related('Registration');
-            // but we only want the REG IDs, so grab the array keys
-            $existing_reg_payment_REG_IDs = ! empty($existing_reg_payment_REG_IDs)
-                ? array_keys($existing_reg_payment_REG_IDs)
-                : array();
-            $this->set_existing_reg_payment_REG_IDs($existing_reg_payment_REG_IDs);
-        }
-
-        return $this->existing_reg_payment_REG_IDs();
-    }
-
-
-    /**
-     * _remove_existing_registration_payments
-     * this calculates the difference between existing relations
-     * to the supplied payment and the new list registration IDs,
-     * removes any related registrations that no longer apply,
-     * and then updates the registration paid fields
-     *
-     * @param \EE_Payment $payment
-     * @param int         $PAY_ID
-     * @return bool;
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _remove_existing_registration_payments(EE_Payment $payment, $PAY_ID = 0)
-    {
-        // newly created payments will have nothing recorded for $PAY_ID
-        if (absint($PAY_ID) === 0) {
-            return false;
-        }
-        $existing_reg_payment_REG_IDs = $this->_get_existing_reg_payment_REG_IDs($payment);
-        if (empty($existing_reg_payment_REG_IDs)) {
-            return false;
-        }
-        /** @type EE_Transaction_Payments $transaction_payments */
-        $transaction_payments = EE_Registry::instance()->load_class('Transaction_Payments');
-
-        return $transaction_payments->delete_registration_payments_and_update_registrations(
-            $payment,
-            array(
-                array(
-                    'PAY_ID' => $payment->ID(),
-                    'REG_ID' => array('IN', $existing_reg_payment_REG_IDs),
-                ),
-            )
-        );
-    }
-
-
-    /**
-     * _update_registration_payments
-     * this applies the payments to the selected registrations
-     * but only if they have not already been paid for
-     *
-     * @param  EE_Transaction $transaction
-     * @param \EE_Payment     $payment
-     * @param array           $REG_IDs
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _update_registration_payments(
-        EE_Transaction $transaction,
-        EE_Payment $payment,
-        $REG_IDs = array()
-    ) {
-        // we can pass our own custom set of registrations to EE_Payment_Processor::process_registration_payments()
-        // so let's do that using our set of REG_IDs from the form
-        $registration_query_where_params = array(
-            'REG_ID' => array('IN', $REG_IDs),
-        );
-        // but add in some conditions regarding payment,
-        // so that we don't apply payments to registrations that are free or have already been paid for
-        // but ONLY if the payment is NOT a refund ( ie: the payment amount is not negative )
-        if (! $payment->is_a_refund()) {
-            $registration_query_where_params['REG_final_price'] = array('!=', 0);
-            $registration_query_where_params['REG_final_price*'] = array('!=', 'REG_paid', true);
-        }
-        $registrations = $transaction->registrations(array($registration_query_where_params));
-        if (! empty($registrations)) {
-            /** @type EE_Payment_Processor $payment_processor */
-            $payment_processor = EE_Registry::instance()->load_core('Payment_Processor');
-            $payment_processor->process_registration_payments($transaction, $payment, $registrations);
-        }
-    }
-
-
-    /**
-     * _process_registration_status_change
-     * This processes requested registration status changes for all the registrations
-     * on a given transaction and (optionally) sends out notifications for the changes.
-     *
-     * @param  EE_Transaction $transaction
-     * @param array           $REG_IDs
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _process_registration_status_change(EE_Transaction $transaction, $REG_IDs = array())
-    {
-        // first if there is no change in status then we get out.
-        if (! isset($this->_req_data['txn_reg_status_change']['reg_status'])
-            || $this->_req_data['txn_reg_status_change']['reg_status'] === 'NAN'
-        ) {
-            // no error message, no change requested, just nothing to do man.
-            return false;
-        }
-        /** @type EE_Transaction_Processor $transaction_processor */
-        $transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
-
-        // made it here dude?  Oh WOW.  K, let's take care of changing the statuses
-        return $transaction_processor->manually_update_registration_statuses(
-            $transaction,
-            sanitize_text_field($this->_req_data['txn_reg_status_change']['reg_status']),
-            array(array('REG_ID' => array('IN', $REG_IDs)))
-        );
-    }
-
-
-    /**
-     * _build_payment_json_response
-     *
-     * @access public
-     * @param \EE_Payment $payment
-     * @param array       $REG_IDs
-     * @param bool | null $delete_txn_reg_status_change
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _build_payment_json_response(
-        EE_Payment $payment,
-        $REG_IDs = array(),
-        $delete_txn_reg_status_change = null
-    ) {
-        // was the payment deleted ?
-        if (is_bool($delete_txn_reg_status_change)) {
-            return array(
-                'PAY_ID'                       => $payment->ID(),
-                'amount'                       => $payment->amount(),
-                'total_paid'                   => $payment->transaction()->paid(),
-                'txn_status'                   => $payment->transaction()->status_ID(),
-                'pay_status'                   => $payment->STS_ID(),
-                'registrations'                => $this->_registration_payment_data_array($REG_IDs),
-                'delete_txn_reg_status_change' => $delete_txn_reg_status_change,
-            );
-        } else {
-            $this->_get_payment_status_array();
-
-            return array(
-                'amount'           => $payment->amount(),
-                'total_paid'       => $payment->transaction()->paid(),
-                'txn_status'       => $payment->transaction()->status_ID(),
-                'pay_status'       => $payment->STS_ID(),
-                'PAY_ID'           => $payment->ID(),
-                'STS_ID'           => $payment->STS_ID(),
-                'status'           => self::$_pay_status[ $payment->STS_ID() ],
-                'date'             => $payment->timestamp('Y-m-d', 'h:i a'),
-                'method'           => strtoupper($payment->source()),
-                'PM_ID'            => $payment->payment_method() ? $payment->payment_method()->ID() : 1,
-                'gateway'          => $payment->payment_method()
-                    ? $payment->payment_method()->admin_name()
-                    : esc_html__('Unknown', 'event_espresso'),
-                'gateway_response' => $payment->gateway_response(),
-                'txn_id_chq_nmbr'  => $payment->txn_id_chq_nmbr(),
-                'po_number'        => $payment->po_number(),
-                'extra_accntng'    => $payment->extra_accntng(),
-                'registrations'    => $this->_registration_payment_data_array($REG_IDs),
-            );
-        }
-    }
-
-
-    /**
-     * delete_payment
-     *    delete a payment or refund made towards a transaction
-     *
-     * @access public
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function delete_payment()
-    {
-        $json_response_data = array('return_data' => false);
-        $PAY_ID = isset($this->_req_data['delete_txn_admin_payment']['PAY_ID'])
-            ? absint($this->_req_data['delete_txn_admin_payment']['PAY_ID'])
-            : 0;
-        $can_delete = EE_Registry::instance()->CAP->current_user_can(
-            'ee_delete_payments',
-            'delete_payment_from_registration_details'
-        );
-        if ($PAY_ID && $can_delete) {
-            $delete_txn_reg_status_change = isset($this->_req_data['delete_txn_reg_status_change'])
-                ? $this->_req_data['delete_txn_reg_status_change']
-                : false;
-            $payment = EEM_Payment::instance()->get_one_by_ID($PAY_ID);
-            if ($payment instanceof EE_Payment) {
-                $REG_IDs = $this->_get_existing_reg_payment_REG_IDs($payment);
-                /** @type EE_Transaction_Payments $transaction_payments */
-                $transaction_payments = EE_Registry::instance()->load_class('Transaction_Payments');
-                if ($transaction_payments->delete_payment_and_update_transaction($payment)) {
-                    $json_response_data['return_data'] = $this->_build_payment_json_response(
-                        $payment,
-                        $REG_IDs,
-                        $delete_txn_reg_status_change
-                    );
-                    if ($delete_txn_reg_status_change) {
-                        $this->_req_data['txn_reg_status_change'] = $delete_txn_reg_status_change;
-                        // MAKE sure we also add the delete_txn_req_status_change to the
-                        // $_REQUEST global because that's how messages will be looking for it.
-                        $_REQUEST['txn_reg_status_change'] = $delete_txn_reg_status_change;
-                        $this->_maybe_send_notifications();
-                        $this->_process_registration_status_change($payment->transaction(), $REG_IDs);
-                    }
-                }
-            } else {
-                EE_Error::add_error(
-                    esc_html__('Valid Payment data could not be retrieved from the database.', 'event_espresso'),
-                    __FILE__,
-                    __FUNCTION__,
-                    __LINE__
-                );
-            }
-        } elseif ($can_delete) {
-            EE_Error::add_error(
-                esc_html__(
-                    'A valid Payment ID was not received, therefore payment form data could not be loaded.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        } else {
-            EE_Error::add_error(
-                esc_html__(
-                    'You do not have access to delete a payment.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        }
-        $notices = EE_Error::get_notices(false, false, false);
-        $this->_template_args = array(
-            'data'      => $json_response_data,
-            'success'   => $notices['success'],
-            'error'     => $notices['errors'],
-            'attention' => $notices['attention'],
-        );
-        $this->_return_json();
-    }
-
-
-    /**
-     * _registration_payment_data_array
-     * adds info for 'owing' and 'paid' for each registration to the json response
-     *
-     * @access protected
-     * @param array $REG_IDs
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _registration_payment_data_array($REG_IDs)
-    {
-        $registration_payment_data = array();
-        // if non empty reg_ids lets get an array of registrations and update the values for the apply_payment/refund rows.
-        if (! empty($REG_IDs)) {
-            $registrations = EEM_Registration::instance()->get_all(array(array('REG_ID' => array('IN', $REG_IDs))));
-            foreach ($registrations as $registration) {
-                if ($registration instanceof EE_Registration) {
-                    $registration_payment_data[ $registration->ID() ] = array(
-                        'paid'  => $registration->pretty_paid(),
-                        'owing' => EEH_Template::format_currency($registration->final_price() - $registration->paid()),
-                    );
-                }
-            }
-        }
-
-        return $registration_payment_data;
-    }
-
-
-    /**
-     * _maybe_send_notifications
-     * determines whether or not the admin has indicated that notifications should be sent.
-     * If so, will toggle a filter switch for delivering registration notices.
-     * If passed an EE_Payment object, then it will trigger payment notifications instead.
-     *
-     * @access protected
-     * @param \EE_Payment | null $payment
-     */
-    protected function _maybe_send_notifications($payment = null)
-    {
-        switch ($payment instanceof EE_Payment) {
-            // payment notifications
-            case true:
-                if (isset($this->_req_data['txn_payments']['send_notifications'])
-                    && filter_var(
-                        $this->_req_data['txn_payments']['send_notifications'],
-                        FILTER_VALIDATE_BOOLEAN
-                    )
-                ) {
-                    $this->_process_payment_notification($payment);
-                }
-                break;
-            // registration notifications
-            case false:
-                if (isset($this->_req_data['txn_reg_status_change']['send_notifications'])
-                    && filter_var(
-                        $this->_req_data['txn_reg_status_change']['send_notifications'],
-                        FILTER_VALIDATE_BOOLEAN
-                    )
-                ) {
-                    add_filter('FHEE__EED_Messages___maybe_registration__deliver_notifications', '__return_true');
-                }
-                break;
-        }
-    }
-
-
-    /**
-     * _send_payment_reminder
-     *    generates HTML for the View Transaction Details Admin page
-     *
-     * @access protected
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _send_payment_reminder()
-    {
-        $TXN_ID = ! empty($this->_req_data['TXN_ID']) ? absint($this->_req_data['TXN_ID']) : false;
-        $transaction = EEM_Transaction::instance()->get_one_by_ID($TXN_ID);
-        $query_args = isset($this->_req_data['redirect_to']) ? array(
-            'action' => $this->_req_data['redirect_to'],
-            'TXN_ID' => $this->_req_data['TXN_ID'],
-        ) : array();
-        do_action(
-            'AHEE__Transactions_Admin_Page___send_payment_reminder__process_admin_payment_reminder',
-            $transaction
-        );
-        $this->_redirect_after_action(
-            false,
-            esc_html__('payment reminder', 'event_espresso'),
-            esc_html__('sent', 'event_espresso'),
-            $query_args,
-            true
-        );
-    }
-
-
-    /**
-     *  get_transactions
-     *    get transactions for given parameters (used by list table)
-     *
-     * @param  int     $perpage how many transactions displayed per page
-     * @param  boolean $count   return the count or objects
-     * @param string   $view
-     * @return mixed int = count || array of transaction objects
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function get_transactions($perpage, $count = false, $view = '')
-    {
-
-        $TXN = EEM_Transaction::instance();
-
-        $start_date = isset($this->_req_data['txn-filter-start-date'])
-            ? wp_strip_all_tags($this->_req_data['txn-filter-start-date'])
-            : date(
-                'm/d/Y',
-                strtotime('-10 year')
-            );
-        $end_date = isset($this->_req_data['txn-filter-end-date'])
-            ? wp_strip_all_tags($this->_req_data['txn-filter-end-date'])
-            : date('m/d/Y');
-
-        // make sure our timestamps start and end right at the boundaries for each day
-        $start_date = date('Y-m-d', strtotime($start_date)) . ' 00:00:00';
-        $end_date = date('Y-m-d', strtotime($end_date)) . ' 23:59:59';
-
-
-        // convert to timestamps
-        $start_date = strtotime($start_date);
-        $end_date = strtotime($end_date);
-
-        // makes sure start date is the lowest value and vice versa
-        $start_date = min($start_date, $end_date);
-        $end_date = max($start_date, $end_date);
-
-        // convert to correct format for query
-        $start_date = EEM_Transaction::instance()->convert_datetime_for_query(
-            'TXN_timestamp',
-            date('Y-m-d H:i:s', $start_date),
-            'Y-m-d H:i:s'
-        );
-        $end_date = EEM_Transaction::instance()->convert_datetime_for_query(
-            'TXN_timestamp',
-            date('Y-m-d H:i:s', $end_date),
-            'Y-m-d H:i:s'
-        );
-
-
-        // set orderby
-        $this->_req_data['orderby'] = ! empty($this->_req_data['orderby']) ? $this->_req_data['orderby'] : '';
-
-        switch ($this->_req_data['orderby']) {
-            case 'TXN_ID':
-                $orderby = 'TXN_ID';
-                break;
-            case 'ATT_fname':
-                $orderby = 'Registration.Attendee.ATT_fname';
-                break;
-            case 'event_name':
-                $orderby = 'Registration.Event.EVT_name';
-                break;
-            default: // 'TXN_timestamp'
-                $orderby = 'TXN_timestamp';
-        }
-
-        $sort = ! empty($this->_req_data['order']) ? $this->_req_data['order'] : 'DESC';
-        $current_page = ! empty($this->_req_data['paged']) ? $this->_req_data['paged'] : 1;
-        $per_page = ! empty($perpage) ? $perpage : 10;
-        $per_page = ! empty($this->_req_data['perpage']) ? $this->_req_data['perpage'] : $per_page;
-
-        $offset = ($current_page - 1) * $per_page;
-        $limit = array($offset, $per_page);
-
-        $_where = array(
-            'TXN_timestamp'          => array('BETWEEN', array($start_date, $end_date)),
-            'Registration.REG_count' => 1,
-        );
-
-        if (isset($this->_req_data['EVT_ID'])) {
-            $_where['Registration.EVT_ID'] = $this->_req_data['EVT_ID'];
-        }
-
-        if (isset($this->_req_data['s'])) {
-            $search_string = '%' . $this->_req_data['s'] . '%';
-            $_where['OR'] = array(
-                'Registration.Event.EVT_name'         => array('LIKE', $search_string),
-                'Registration.Event.EVT_desc'         => array('LIKE', $search_string),
-                'Registration.Event.EVT_short_desc'   => array('LIKE', $search_string),
-                'Registration.Attendee.ATT_full_name' => array('LIKE', $search_string),
-                'Registration.Attendee.ATT_fname'     => array('LIKE', $search_string),
-                'Registration.Attendee.ATT_lname'     => array('LIKE', $search_string),
-                'Registration.Attendee.ATT_short_bio' => array('LIKE', $search_string),
-                'Registration.Attendee.ATT_email'     => array('LIKE', $search_string),
-                'Registration.Attendee.ATT_address'   => array('LIKE', $search_string),
-                'Registration.Attendee.ATT_address2'  => array('LIKE', $search_string),
-                'Registration.Attendee.ATT_city'      => array('LIKE', $search_string),
-                'Registration.REG_final_price'        => array('LIKE', $search_string),
-                'Registration.REG_code'               => array('LIKE', $search_string),
-                'Registration.REG_count'              => array('LIKE', $search_string),
-                'Registration.REG_group_size'         => array('LIKE', $search_string),
-                'Registration.Ticket.TKT_name'        => array('LIKE', $search_string),
-                'Registration.Ticket.TKT_description' => array('LIKE', $search_string),
-                'Payment.PAY_source'                  => array('LIKE', $search_string),
-                'Payment.Payment_Method.PMD_name'     => array('LIKE', $search_string),
-                'TXN_session_data'                    => array('LIKE', $search_string),
-                'Payment.PAY_txn_id_chq_nmbr'         => array('LIKE', $search_string),
-            );
-        }
-
-        // failed transactions
-        $failed = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'failed' && ! $count)
-                  || ($count && $view === 'failed');
-        $abandoned = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'abandoned' && ! $count)
-                     || ($count && $view === 'abandoned');
-        $incomplete = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'incomplete' && ! $count)
-                      || ($count && $view === 'incomplete');
-
-        if ($failed) {
-            $_where['STS_ID'] = EEM_Transaction::failed_status_code;
-        } elseif ($abandoned) {
-            $_where['STS_ID'] = EEM_Transaction::abandoned_status_code;
-        } elseif ($incomplete) {
-            $_where['STS_ID'] = EEM_Transaction::incomplete_status_code;
-        } else {
-            $_where['STS_ID'] = array('!=', EEM_Transaction::failed_status_code);
-            $_where['STS_ID*'] = array('!=', EEM_Transaction::abandoned_status_code);
-        }
-
-        $query_params = apply_filters(
-            'FHEE__Transactions_Admin_Page___get_transactions_query_params',
-            array(
-                $_where,
-                'order_by'                 => array($orderby => $sort),
-                'limit'                    => $limit,
-                'default_where_conditions' => EEM_Base::default_where_conditions_this_only,
-            ),
-            $this->_req_data,
-            $view,
-            $count
-        );
-
-        $transactions = $count
-            ? $TXN->count(array($query_params[0]), 'TXN_ID', true)
-            : $TXN->get_all($query_params);
-
-        return $transactions;
-    }
-
-
-    /**
-     * @since $VID:$
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    public function recalculateLineItems()
-    {
-        $TXN_ID = ! empty($this->_req_data['TXN_ID']) ? absint($this->_req_data['TXN_ID']) : false;
-        /** @var EE_Transaction $transaction */
-        $transaction = EEM_Transaction::instance()->get_one_by_ID($TXN_ID);
-        $total_line_item = $transaction->total_line_item(false);
-        $success = false;
-        if ($total_line_item instanceof EE_Line_Item) {
-            EEH_Line_Item::resetIsTaxableForTickets($total_line_item);
-            $success = EEH_Line_Item::apply_taxes($total_line_item, true);
-        }
-        $this->_redirect_after_action(
-            (bool) $success,
-            esc_html__('Transaction taxes and totals', 'event_espresso'),
-            esc_html__('recalculated', 'event_espresso'),
-            isset($this->_req_data['redirect_to'])
-                ? array(
-                'action' => $this->_req_data['redirect_to'],
-                'TXN_ID' => $this->_req_data['TXN_ID'],
-            )
-                : array(),
-            true
-        );
-    }
+	/**
+	 * @var EE_Transaction
+	 */
+	private $_transaction;
+
+	/**
+	 * @var EE_Session
+	 */
+	private $_session;
+
+	/**
+	 * @var array $_txn_status
+	 */
+	private static $_txn_status;
+
+	/**
+	 * @var array $_pay_status
+	 */
+	private static $_pay_status;
+
+	/**
+	 * @var array $_existing_reg_payment_REG_IDs
+	 */
+	protected $_existing_reg_payment_REG_IDs;
+
+
+	/**
+	 *    _init_page_props
+	 *
+	 * @return void
+	 */
+	protected function _init_page_props()
+	{
+		$this->page_slug = TXN_PG_SLUG;
+		$this->page_label = esc_html__('Transactions', 'event_espresso');
+		$this->_admin_base_url = TXN_ADMIN_URL;
+		$this->_admin_base_path = TXN_ADMIN;
+	}
+
+
+	/**
+	 *    _ajax_hooks
+	 *
+	 * @return void
+	 */
+	protected function _ajax_hooks()
+	{
+		add_action('wp_ajax_espresso_apply_payment', array($this, 'apply_payments_or_refunds'));
+		add_action('wp_ajax_espresso_apply_refund', array($this, 'apply_payments_or_refunds'));
+		add_action('wp_ajax_espresso_delete_payment', array($this, 'delete_payment'));
+	}
+
+
+	/**
+	 *    _define_page_props
+	 *
+	 * @return void
+	 */
+	protected function _define_page_props()
+	{
+		$this->_admin_page_title = $this->page_label;
+		$this->_labels = array(
+			'buttons' => array(
+				'add'    => esc_html__('Add New Transaction', 'event_espresso'),
+				'edit'   => esc_html__('Edit Transaction', 'event_espresso'),
+				'delete' => esc_html__('Delete Transaction', 'event_espresso'),
+			),
+		);
+	}
+
+
+	/**
+	 *        grab url requests and route them
+	 *
+	 * @access private
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function _set_page_routes()
+	{
+
+		$this->_set_transaction_status_array();
+
+		$txn_id = ! empty($this->_req_data['TXN_ID'])
+				  && ! is_array($this->_req_data['TXN_ID'])
+			? $this->_req_data['TXN_ID']
+			: 0;
+
+		$this->_page_routes = array(
+
+			'default' => array(
+				'func'       => '_transactions_overview_list_table',
+				'capability' => 'ee_read_transactions',
+			),
+
+			'view_transaction' => array(
+				'func'       => '_transaction_details',
+				'capability' => 'ee_read_transaction',
+				'obj_id'     => $txn_id,
+			),
+
+			'send_payment_reminder' => array(
+				'func'       => '_send_payment_reminder',
+				'noheader'   => true,
+				'capability' => 'ee_send_message',
+			),
+
+			'espresso_apply_payment' => array(
+				'func'       => 'apply_payments_or_refunds',
+				'noheader'   => true,
+				'capability' => 'ee_edit_payments',
+			),
+
+			'espresso_apply_refund' => array(
+				'func'       => 'apply_payments_or_refunds',
+				'noheader'   => true,
+				'capability' => 'ee_edit_payments',
+			),
+
+			'espresso_delete_payment' => array(
+				'func'       => 'delete_payment',
+				'noheader'   => true,
+				'capability' => 'ee_delete_payments',
+			),
+
+			'espresso_recalculate_line_items' => array(
+				'func'       => 'recalculateLineItems',
+				'noheader'   => true,
+				'capability' => 'ee_edit_payments',
+			),
+
+		);
+	}
+
+
+	protected function _set_page_config()
+	{
+		$this->_page_config = array(
+			'default'          => array(
+				'nav'           => array(
+					'label' => esc_html__('Overview', 'event_espresso'),
+					'order' => 10,
+				),
+				'list_table'    => 'EE_Admin_Transactions_List_Table',
+				'help_tabs'     => array(
+					'transactions_overview_help_tab'                       => array(
+						'title'    => esc_html__('Transactions Overview', 'event_espresso'),
+						'filename' => 'transactions_overview',
+					),
+					'transactions_overview_table_column_headings_help_tab' => array(
+						'title'    => esc_html__('Transactions Table Column Headings', 'event_espresso'),
+						'filename' => 'transactions_overview_table_column_headings',
+					),
+					'transactions_overview_views_filters_help_tab'         => array(
+						'title'    => esc_html__('Transaction Views & Filters & Search', 'event_espresso'),
+						'filename' => 'transactions_overview_views_filters_search',
+					),
+				),
+				'help_tour'     => array('Transactions_Overview_Help_Tour'),
+				/**
+				 * commented out because currently we are not displaying tips for transaction list table status but this
+				 * may change in a later iteration so want to keep the code for then.
+				 */
+				// 'qtips' => array( 'Transactions_List_Table_Tips' ),
+				'require_nonce' => false,
+			),
+			'view_transaction' => array(
+				'nav'       => array(
+					'label'      => esc_html__('View Transaction', 'event_espresso'),
+					'order'      => 5,
+					'url'        => isset($this->_req_data['TXN_ID'])
+						? add_query_arg(array('TXN_ID' => $this->_req_data['TXN_ID']), $this->_current_page_view_url)
+						: $this->_admin_base_url,
+					'persistent' => false,
+				),
+				'help_tabs' => array(
+					'transactions_view_transaction_help_tab'                                              => array(
+						'title'    => esc_html__('View Transaction', 'event_espresso'),
+						'filename' => 'transactions_view_transaction',
+					),
+					'transactions_view_transaction_transaction_details_table_help_tab'                    => array(
+						'title'    => esc_html__('Transaction Details Table', 'event_espresso'),
+						'filename' => 'transactions_view_transaction_transaction_details_table',
+					),
+					'transactions_view_transaction_attendees_registered_help_tab'                         => array(
+						'title'    => esc_html__('Attendees Registered', 'event_espresso'),
+						'filename' => 'transactions_view_transaction_attendees_registered',
+					),
+					'transactions_view_transaction_views_primary_registrant_billing_information_help_tab' => array(
+						'title'    => esc_html__('Primary Registrant & Billing Information', 'event_espresso'),
+						'filename' => 'transactions_view_transaction_primary_registrant_billing_information',
+					),
+				),
+				'qtips'     => array('Transaction_Details_Tips'),
+				'help_tour' => array('Transaction_Details_Help_Tour'),
+				'metaboxes' => array('_transaction_details_metaboxes'),
+
+				'require_nonce' => false,
+			),
+		);
+	}
+
+
+	/**
+	 * The below methods aren't used by this class currently
+	 */
+	protected function _add_screen_options()
+	{
+		// noop
+	}
+
+
+	protected function _add_feature_pointers()
+	{
+		// noop
+	}
+
+
+	public function admin_init()
+	{
+		// IF a registration was JUST added via the admin...
+		if (isset(
+			$this->_req_data['redirect_from'],
+			$this->_req_data['EVT_ID'],
+			$this->_req_data['event_name']
+		)) {
+			// then set a cookie so that we can block any attempts to use
+			// the back button as a way to enter another registration.
+			setcookie(
+				'ee_registration_added',
+				$this->_req_data['EVT_ID'],
+				time() + WEEK_IN_SECONDS,
+				'/'
+			);
+			// and update the global
+			$_COOKIE['ee_registration_added'] = $this->_req_data['EVT_ID'];
+		}
+		EE_Registry::$i18n_js_strings['invalid_server_response'] = esc_html__(
+			'An error occurred! Your request may have been processed, but a valid response from the server was not received. Please refresh the page and try again.',
+			'event_espresso'
+		);
+		EE_Registry::$i18n_js_strings['error_occurred'] = esc_html__(
+			'An error occurred! Please refresh the page and try again.',
+			'event_espresso'
+		);
+		EE_Registry::$i18n_js_strings['txn_status_array'] = self::$_txn_status;
+		EE_Registry::$i18n_js_strings['pay_status_array'] = self::$_pay_status;
+		EE_Registry::$i18n_js_strings['payments_total'] = esc_html__('Payments Total', 'event_espresso');
+		EE_Registry::$i18n_js_strings['transaction_overpaid'] = esc_html__(
+			'This transaction has been overpaid ! Payments Total',
+			'event_espresso'
+		);
+	}
+
+
+	public function admin_notices()
+	{
+		// noop
+	}
+
+
+	public function admin_footer_scripts()
+	{
+		// noop
+	}
+
+
+	/**
+	 * _set_transaction_status_array
+	 * sets list of transaction statuses
+	 *
+	 * @access private
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	private function _set_transaction_status_array()
+	{
+		self::$_txn_status = EEM_Transaction::instance()->status_array(true);
+	}
+
+
+	/**
+	 * get_transaction_status_array
+	 * return the transaction status array for wp_list_table
+	 *
+	 * @access public
+	 * @return array
+	 */
+	public function get_transaction_status_array()
+	{
+		return self::$_txn_status;
+	}
+
+
+	/**
+	 *    get list of payment statuses
+	 *
+	 * @access private
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	private function _get_payment_status_array()
+	{
+		self::$_pay_status = EEM_Payment::instance()->status_array(true);
+		$this->_template_args['payment_status'] = self::$_pay_status;
+	}
+
+
+	/**
+	 *    _add_screen_options_default
+	 *
+	 * @access protected
+	 * @return void
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _add_screen_options_default()
+	{
+		$this->_per_page_screen_option();
+	}
+
+
+	/**
+	 * load_scripts_styles
+	 *
+	 * @access public
+	 * @return void
+	 */
+	public function load_scripts_styles()
+	{
+		// enqueue style
+		wp_register_style(
+			'espresso_txn',
+			TXN_ASSETS_URL . 'espresso_transactions_admin.css',
+			array(),
+			EVENT_ESPRESSO_VERSION
+		);
+		wp_enqueue_style('espresso_txn');
+		// scripts
+		wp_register_script(
+			'espresso_txn',
+			TXN_ASSETS_URL . 'espresso_transactions_admin.js',
+			array(
+				'ee_admin_js',
+				'ee-datepicker',
+				'jquery-ui-datepicker',
+				'jquery-ui-draggable',
+				'ee-dialog',
+				'ee-accounting',
+				'ee-serialize-full-array',
+			),
+			EVENT_ESPRESSO_VERSION,
+			true
+		);
+		wp_enqueue_script('espresso_txn');
+	}
+
+
+	/**
+	 *    load_scripts_styles_view_transaction
+	 *
+	 * @access public
+	 * @return void
+	 */
+	public function load_scripts_styles_view_transaction()
+	{
+		// styles
+		wp_enqueue_style('espresso-ui-theme');
+	}
+
+
+	/**
+	 *    load_scripts_styles_default
+	 *
+	 * @access public
+	 * @return void
+	 */
+	public function load_scripts_styles_default()
+	{
+		// styles
+		wp_enqueue_style('espresso-ui-theme');
+	}
+
+
+	/**
+	 *    _set_list_table_views_default
+	 *
+	 * @access protected
+	 * @return void
+	 */
+	protected function _set_list_table_views_default()
+	{
+		$this->_views = array(
+			'all'        => array(
+				'slug'  => 'all',
+				'label' => esc_html__('View All Transactions', 'event_espresso'),
+				'count' => 0,
+			),
+			'abandoned'  => array(
+				'slug'  => 'abandoned',
+				'label' => esc_html__('Abandoned Transactions', 'event_espresso'),
+				'count' => 0,
+			),
+			'incomplete' => array(
+				'slug'  => 'incomplete',
+				'label' => esc_html__('Incomplete Transactions', 'event_espresso'),
+				'count' => 0,
+			),
+		);
+		if (/**
+		 * Filters whether a link to the "Failed Transactions" list table
+		 * appears on the Transactions Admin Page list table.
+		 * List display can be turned back on via the following:
+		 * add_filter(
+		 *     'FHEE__Transactions_Admin_Page___set_list_table_views_default__display_failed_txns_list',
+		 *     '__return_true'
+		 * );
+		 *
+		 * @since 4.9.70.p
+		 * @param boolean                 $display_failed_txns_list
+		 * @param Transactions_Admin_Page $this
+		 */
+		apply_filters(
+			'FHEE__Transactions_Admin_Page___set_list_table_views_default__display_failed_txns_list',
+			false,
+			$this
+		)
+		) {
+			$this->_views['failed'] = array(
+				'slug'  => 'failed',
+				'label' => esc_html__('Failed Transactions', 'event_espresso'),
+				'count' => 0,
+			);
+		}
+	}
+
+
+	/**
+	 * _set_transaction_object
+	 * This sets the _transaction property for the transaction details screen
+	 *
+	 * @access private
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws RuntimeException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	private function _set_transaction_object()
+	{
+		if ($this->_transaction instanceof EE_Transaction) {
+			return;
+		} //get out we've already set the object
+
+		$TXN_ID = ! empty($this->_req_data['TXN_ID'])
+			? absint($this->_req_data['TXN_ID'])
+			: false;
+
+		// get transaction object
+		$this->_transaction = EEM_Transaction::instance()->get_one_by_ID($TXN_ID);
+		$this->_session = $this->_transaction instanceof EE_Transaction
+			? $this->_transaction->session_data()
+			: null;
+		if ($this->_transaction instanceof EE_Transaction) {
+			$this->_transaction->verify_abandoned_transaction_status();
+		}
+
+		if (! $this->_transaction instanceof EE_Transaction) {
+			$error_msg = sprintf(
+				esc_html__(
+					'An error occurred and the details for the transaction with the ID # %d could not be retrieved.',
+					'event_espresso'
+				),
+				$TXN_ID
+			);
+			EE_Error::add_error($error_msg, __FILE__, __FUNCTION__, __LINE__);
+		}
+	}
+
+
+	/**
+	 *    _transaction_legend_items
+	 *
+	 * @access protected
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _transaction_legend_items()
+	{
+		EE_Registry::instance()->load_helper('MSG_Template');
+		$items = array();
+
+		if (EE_Registry::instance()->CAP->current_user_can(
+			'ee_read_global_messages',
+			'view_filtered_messages'
+		)) {
+			$related_for_icon = EEH_MSG_Template::get_message_action_icon('see_notifications_for');
+			if (is_array($related_for_icon)
+				&& isset($related_for_icon['css_class'], $related_for_icon['label'])
+			) {
+				$items['view_related_messages'] = array(
+					'class' => $related_for_icon['css_class'],
+					'desc'  => $related_for_icon['label'],
+				);
+			}
+		}
+
+		$items = apply_filters(
+			'FHEE__Transactions_Admin_Page___transaction_legend_items__items',
+			array_merge(
+				$items,
+				array(
+					'view_details'          => array(
+						'class' => 'dashicons dashicons-cart',
+						'desc'  => esc_html__('View Transaction Details', 'event_espresso'),
+					),
+					'view_invoice'          => array(
+						'class' => 'dashicons dashicons-media-spreadsheet',
+						'desc'  => esc_html__('View Transaction Invoice', 'event_espresso'),
+					),
+					'view_receipt'          => array(
+						'class' => 'dashicons dashicons-media-default',
+						'desc'  => esc_html__('View Transaction Receipt', 'event_espresso'),
+					),
+					'view_registration'     => array(
+						'class' => 'dashicons dashicons-clipboard',
+						'desc'  => esc_html__('View Registration Details', 'event_espresso'),
+					),
+					'payment_overview_link' => array(
+						'class' => 'dashicons dashicons-money',
+						'desc'  => esc_html__('Make Payment on Frontend', 'event_espresso'),
+					),
+				)
+			)
+		);
+
+		if (EEH_MSG_Template::is_mt_active('payment_reminder')
+			&& EE_Registry::instance()->CAP->current_user_can(
+				'ee_send_message',
+				'espresso_transactions_send_payment_reminder'
+			)
+		) {
+			$items['send_payment_reminder'] = array(
+				'class' => 'dashicons dashicons-email-alt',
+				'desc'  => esc_html__('Send Payment Reminder', 'event_espresso'),
+			);
+		} else {
+			$items['blank*'] = array(
+				'class' => '',
+				'desc'  => '',
+			);
+		}
+		$more_items = apply_filters(
+			'FHEE__Transactions_Admin_Page___transaction_legend_items__more_items',
+			array(
+				'overpaid'   => array(
+					'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::overpaid_status_code,
+					'desc'  => EEH_Template::pretty_status(
+						EEM_Transaction::overpaid_status_code,
+						false,
+						'sentence'
+					),
+				),
+				'complete'   => array(
+					'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::complete_status_code,
+					'desc'  => EEH_Template::pretty_status(
+						EEM_Transaction::complete_status_code,
+						false,
+						'sentence'
+					),
+				),
+				'incomplete' => array(
+					'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::incomplete_status_code,
+					'desc'  => EEH_Template::pretty_status(
+						EEM_Transaction::incomplete_status_code,
+						false,
+						'sentence'
+					),
+				),
+				'abandoned'  => array(
+					'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::abandoned_status_code,
+					'desc'  => EEH_Template::pretty_status(
+						EEM_Transaction::abandoned_status_code,
+						false,
+						'sentence'
+					),
+				),
+				'failed'     => array(
+					'class' => 'ee-status-legend ee-status-legend-' . EEM_Transaction::failed_status_code,
+					'desc'  => EEH_Template::pretty_status(
+						EEM_Transaction::failed_status_code,
+						false,
+						'sentence'
+					),
+				),
+			)
+		);
+
+		return array_merge($items, $more_items);
+	}
+
+
+	/**
+	 *    _transactions_overview_list_table
+	 *
+	 * @access protected
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _transactions_overview_list_table()
+	{
+		$this->_admin_page_title = esc_html__('Transactions', 'event_espresso');
+		$event = isset($this->_req_data['EVT_ID'])
+			? EEM_Event::instance()->get_one_by_ID($this->_req_data['EVT_ID'])
+			: null;
+		$this->_template_args['admin_page_header'] = $event instanceof EE_Event
+			? sprintf(
+				esc_html__(
+					'%sViewing Transactions for the Event: %s%s',
+					'event_espresso'
+				),
+				'<h3>',
+				'<a href="'
+				. EE_Admin_Page::add_query_args_and_nonce(
+					array('action' => 'edit', 'post' => $event->ID()),
+					EVENTS_ADMIN_URL
+				)
+				. '" title="'
+				. esc_attr__(
+					'Click to Edit event',
+					'event_espresso'
+				)
+				. '">' . $event->name() . '</a>',
+				'</h3>'
+			)
+			: '';
+		$this->_template_args['after_list_table'] = $this->_display_legend($this->_transaction_legend_items());
+		$this->display_admin_list_table_page_with_no_sidebar();
+	}
+
+
+	/**
+	 *    _transaction_details
+	 * generates HTML for the View Transaction Details Admin page
+	 *
+	 * @access protected
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws RuntimeException
+	 * @throws ReflectionException
+	 */
+	protected function _transaction_details()
+	{
+		do_action('AHEE__Transactions_Admin_Page__transaction_details__start', $this->_transaction);
+
+		$this->_set_transaction_status_array();
+
+		$this->_template_args = array();
+		$this->_template_args['transactions_page'] = $this->_wp_page_slug;
+
+		$this->_set_transaction_object();
+
+		if (! $this->_transaction instanceof EE_Transaction) {
+			return;
+		}
+		$primary_registration = $this->_transaction->primary_registration();
+		$attendee = $primary_registration instanceof EE_Registration
+			? $primary_registration->attendee()
+			: null;
+
+		$this->_template_args['txn_nmbr']['value'] = $this->_transaction->ID();
+		$this->_template_args['txn_nmbr']['label'] = esc_html__('Transaction Number', 'event_espresso');
+
+		$this->_template_args['txn_datetime']['value'] = $this->_transaction->get_i18n_datetime('TXN_timestamp');
+		$this->_template_args['txn_datetime']['label'] = esc_html__('Date', 'event_espresso');
+
+		$this->_template_args['txn_status']['value'] = self::$_txn_status[ $this->_transaction->status_ID() ];
+		$this->_template_args['txn_status']['label'] = esc_html__('Transaction Status', 'event_espresso');
+		$this->_template_args['txn_status']['class'] = 'status-' . $this->_transaction->status_ID();
+
+		$this->_template_args['grand_total'] = $this->_transaction->total();
+		$this->_template_args['total_paid'] = $this->_transaction->paid();
+
+		$amount_due = $this->_transaction->total() - $this->_transaction->paid();
+		$this->_template_args['amount_due'] = EEH_Template::format_currency(
+			$amount_due,
+			true
+		);
+		if (EE_Registry::instance()->CFG->currency->sign_b4) {
+			$this->_template_args['amount_due'] = EE_Registry::instance()->CFG->currency->sign
+												  . $this->_template_args['amount_due'];
+		} else {
+			$this->_template_args['amount_due'] .= EE_Registry::instance()->CFG->currency->sign;
+		}
+		$this->_template_args['amount_due_class'] = '';
+
+		if ($this->_transaction->paid() === $this->_transaction->total()) {
+			// paid in full
+			$this->_template_args['amount_due'] = false;
+		} elseif ($this->_transaction->paid() > $this->_transaction->total()) {
+			// overpaid
+			$this->_template_args['amount_due_class'] = 'txn-overview-no-payment-spn';
+		} elseif ($this->_transaction->total() > (float) 0) {
+			if ($this->_transaction->paid() > (float) 0) {
+				// monies owing
+				$this->_template_args['amount_due_class'] = 'txn-overview-part-payment-spn';
+			} elseif ($this->_transaction->paid() === (float) 0) {
+				// no payments made yet
+				$this->_template_args['amount_due_class'] = 'txn-overview-no-payment-spn';
+			}
+		} elseif ($this->_transaction->total() === (float) 0) {
+			// free event
+			$this->_template_args['amount_due'] = false;
+		}
+
+		$payment_method = $this->_transaction->payment_method();
+
+		$this->_template_args['method_of_payment_name'] = $payment_method instanceof EE_Payment_Method
+			? $payment_method->admin_name()
+			: esc_html__('Unknown', 'event_espresso');
+
+		$this->_template_args['currency_sign'] = EE_Registry::instance()->CFG->currency->sign;
+		// link back to overview
+		$this->_template_args['txn_overview_url'] = ! empty($_SERVER['HTTP_REFERER'])
+			? $_SERVER['HTTP_REFERER']
+			: TXN_ADMIN_URL;
+
+
+		// next link
+		$next_txn = $this->_transaction->next(
+			null,
+			array(array('STS_ID' => array('!=', EEM_Transaction::failed_status_code))),
+			'TXN_ID'
+		);
+		$this->_template_args['next_transaction'] = $next_txn
+			? $this->_next_link(
+				EE_Admin_Page::add_query_args_and_nonce(
+					array('action' => 'view_transaction', 'TXN_ID' => $next_txn['TXN_ID']),
+					TXN_ADMIN_URL
+				),
+				'dashicons dashicons-arrow-right ee-icon-size-22'
+			)
+			: '';
+		// previous link
+		$previous_txn = $this->_transaction->previous(
+			null,
+			array(array('STS_ID' => array('!=', EEM_Transaction::failed_status_code))),
+			'TXN_ID'
+		);
+		$this->_template_args['previous_transaction'] = $previous_txn
+			? $this->_previous_link(
+				EE_Admin_Page::add_query_args_and_nonce(
+					array('action' => 'view_transaction', 'TXN_ID' => $previous_txn['TXN_ID']),
+					TXN_ADMIN_URL
+				),
+				'dashicons dashicons-arrow-left ee-icon-size-22'
+			)
+			: '';
+
+		// were we just redirected here after adding a new registration ???
+		if (isset(
+			$this->_req_data['redirect_from'],
+			$this->_req_data['EVT_ID'],
+			$this->_req_data['event_name']
+		)) {
+			if (EE_Registry::instance()->CAP->current_user_can(
+				'ee_edit_registrations',
+				'espresso_registrations_new_registration',
+				$this->_req_data['EVT_ID']
+			)) {
+				$this->_admin_page_title .= '<a id="add-new-registration" class="add-new-h2 button-primary" href="';
+				$this->_admin_page_title .= EE_Admin_Page::add_query_args_and_nonce(
+					array(
+						'page'     => 'espresso_registrations',
+						'action'   => 'new_registration',
+						'return'   => 'default',
+						'TXN_ID'   => $this->_transaction->ID(),
+						'event_id' => $this->_req_data['EVT_ID'],
+					),
+					REG_ADMIN_URL
+				);
+				$this->_admin_page_title .= '">';
+
+				$this->_admin_page_title .= sprintf(
+					esc_html__('Add Another New Registration to Event: "%1$s" ?', 'event_espresso'),
+					htmlentities(urldecode($this->_req_data['event_name']), ENT_QUOTES, 'UTF-8')
+				);
+				$this->_admin_page_title .= '</a>';
+			}
+			EE_Registry::instance()->SSN->clear_session(__CLASS__, __FUNCTION__);
+		}
+		// grab messages at the last second
+		$this->_template_args['notices'] = EE_Error::get_notices();
+		// path to template
+		$template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_header.template.php';
+		$this->_template_args['admin_page_header'] = EEH_Template::display_template(
+			$template_path,
+			$this->_template_args,
+			true
+		);
+
+		// the details template wrapper
+		$this->display_admin_page_with_sidebar();
+	}
+
+
+	/**
+	 *        _transaction_details_metaboxes
+	 *
+	 * @access protected
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws RuntimeException
+	 * @throws ReflectionException
+	 */
+	protected function _transaction_details_metaboxes()
+	{
+
+		$this->_set_transaction_object();
+
+		if (! $this->_transaction instanceof EE_Transaction) {
+			return;
+		}
+		add_meta_box(
+			'edit-txn-details-mbox',
+			esc_html__('Transaction Details', 'event_espresso'),
+			array($this, 'txn_details_meta_box'),
+			$this->_wp_page_slug,
+			'normal',
+			'high'
+		);
+		add_meta_box(
+			'edit-txn-attendees-mbox',
+			esc_html__('Attendees Registered in this Transaction', 'event_espresso'),
+			array($this, 'txn_attendees_meta_box'),
+			$this->_wp_page_slug,
+			'normal',
+			'high',
+			array('TXN_ID' => $this->_transaction->ID())
+		);
+		add_meta_box(
+			'edit-txn-registrant-mbox',
+			esc_html__('Primary Contact', 'event_espresso'),
+			array($this, 'txn_registrant_side_meta_box'),
+			$this->_wp_page_slug,
+			'side',
+			'high'
+		);
+		add_meta_box(
+			'edit-txn-billing-info-mbox',
+			esc_html__('Billing Information', 'event_espresso'),
+			array($this, 'txn_billing_info_side_meta_box'),
+			$this->_wp_page_slug,
+			'side',
+			'high'
+		);
+	}
+
+
+	/**
+	 * Callback for transaction actions metabox.
+	 *
+	 * @param EE_Transaction|null $transaction
+	 * @return string
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	public function getActionButtons(EE_Transaction $transaction = null)
+	{
+		$content = '';
+		$actions = array();
+		if (! $transaction instanceof EE_Transaction) {
+			return $content;
+		}
+		/** @var EE_Registration $primary_registration */
+		$primary_registration = $transaction->primary_registration();
+		$attendee = $primary_registration instanceof EE_Registration
+			? $primary_registration->attendee()
+			: null;
+
+		if ($attendee instanceof EE_Attendee
+			&& EE_Registry::instance()->CAP->current_user_can(
+				'ee_send_message',
+				'espresso_transactions_send_payment_reminder'
+			)
+		) {
+			$actions['payment_reminder'] =
+				EEH_MSG_Template::is_mt_active('payment_reminder')
+				&& $this->_transaction->status_ID() !== EEM_Transaction::complete_status_code
+				&& $this->_transaction->status_ID() !== EEM_Transaction::overpaid_status_code
+					? EEH_Template::get_button_or_link(
+						EE_Admin_Page::add_query_args_and_nonce(
+							array(
+								'action'      => 'send_payment_reminder',
+								'TXN_ID'      => $this->_transaction->ID(),
+								'redirect_to' => 'view_transaction',
+							),
+							TXN_ADMIN_URL
+						),
+						esc_html__(' Send Payment Reminder', 'event_espresso'),
+						'button secondary-button',
+						'dashicons dashicons-email-alt'
+					)
+					: '';
+		}
+
+		if (EE_Registry::instance()->CAP->current_user_can(
+			'ee_edit_payments',
+			'espresso_transactions_recalculate_line_items'
+		)
+		) {
+			$actions['recalculate_line_items'] = EEH_Template::get_button_or_link(
+				EE_Admin_Page::add_query_args_and_nonce(
+					array(
+						'action'      => 'espresso_recalculate_line_items',
+						'TXN_ID'      => $this->_transaction->ID(),
+						'redirect_to' => 'view_transaction',
+					),
+					TXN_ADMIN_URL
+				),
+				esc_html__(' Recalculate Taxes and Total', 'event_espresso'),
+				'button secondary-button',
+				'dashicons dashicons-update'
+			);
+		}
+
+		if ($primary_registration instanceof EE_Registration
+			&& EEH_MSG_Template::is_mt_active('receipt')
+		) {
+			$actions['receipt'] = EEH_Template::get_button_or_link(
+				$primary_registration->receipt_url(),
+				esc_html__('View Receipt', 'event_espresso'),
+				'button secondary-button',
+				'dashicons dashicons-media-default'
+			);
+		}
+
+		if ($primary_registration instanceof EE_Registration
+			&& EEH_MSG_Template::is_mt_active('invoice')
+		) {
+			$actions['invoice'] = EEH_Template::get_button_or_link(
+				$primary_registration->invoice_url(),
+				esc_html__('View Invoice', 'event_espresso'),
+				'button secondary-button',
+				'dashicons dashicons-media-spreadsheet'
+			);
+		}
+		$actions = array_filter(
+			apply_filters('FHEE__Transactions_Admin_Page__getActionButtons__actions', $actions, $transaction)
+		);
+		if ($actions) {
+			$content = '<ul>';
+			$content .= '<li>' . implode('</li><li>', $actions) . '</li>';
+			$content .= '</uL>';
+		}
+		return $content;
+	}
+
+
+	/**
+	 * txn_details_meta_box
+	 * generates HTML for the Transaction main meta box
+	 *
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws RuntimeException
+	 * @throws ReflectionException
+	 */
+	public function txn_details_meta_box()
+	{
+		$this->_set_transaction_object();
+		$this->_template_args['TXN_ID'] = $this->_transaction->ID();
+		$this->_template_args['attendee'] = $this->_transaction->primary_registration() instanceof EE_Registration
+			? $this->_transaction->primary_registration()->attendee()
+			: null;
+		$this->_template_args['can_edit_payments'] = EE_Registry::instance()->CAP->current_user_can(
+			'ee_edit_payments',
+			'apply_payment_or_refund_from_registration_details'
+		);
+		$this->_template_args['can_delete_payments'] = EE_Registry::instance()->CAP->current_user_can(
+			'ee_delete_payments',
+			'delete_payment_from_registration_details'
+		);
+
+		// get line table
+		EEH_Autoloader::register_line_item_display_autoloaders();
+		$Line_Item_Display = new EE_Line_Item_Display(
+			'admin_table',
+			'EE_Admin_Table_Line_Item_Display_Strategy'
+		);
+		$this->_template_args['line_item_table'] = $Line_Item_Display->display_line_item(
+			$this->_transaction->total_line_item()
+		);
+		$this->_template_args['REG_code'] = $this->_transaction->primary_registration()->reg_code();
+
+		// process taxes
+		$taxes = $this->_transaction->line_items(array(array('LIN_type' => EEM_Line_Item::type_tax)));
+		$this->_template_args['taxes'] = ! empty($taxes) ? $taxes : false;
+
+		$this->_template_args['grand_total'] = EEH_Template::format_currency(
+			$this->_transaction->total(),
+			false,
+			false
+		);
+		$this->_template_args['grand_raw_total'] = $this->_transaction->total();
+		$this->_template_args['TXN_status'] = $this->_transaction->status_ID();
+
+		// process payment details
+		$payments = $this->_transaction->payments();
+		if (! empty($payments)) {
+			$this->_template_args['payments'] = $payments;
+			$this->_template_args['existing_reg_payments'] = $this->_get_registration_payment_IDs($payments);
+		} else {
+			$this->_template_args['payments'] = false;
+			$this->_template_args['existing_reg_payments'] = array();
+		}
+
+		$this->_template_args['edit_payment_url'] = add_query_arg(array('action' => 'edit_payment'), TXN_ADMIN_URL);
+		$this->_template_args['delete_payment_url'] = add_query_arg(
+			array('action' => 'espresso_delete_payment'),
+			TXN_ADMIN_URL
+		);
+
+		if (isset($txn_details['invoice_number'])) {
+			$this->_template_args['txn_details']['invoice_number']['value'] = $this->_template_args['REG_code'];
+			$this->_template_args['txn_details']['invoice_number']['label'] = esc_html__(
+				'Invoice Number',
+				'event_espresso'
+			);
+		}
+
+		$this->_template_args['txn_details']['registration_session']['value'] = $this->_transaction
+			->primary_registration()
+			->session_ID();
+		$this->_template_args['txn_details']['registration_session']['label'] = esc_html__(
+			'Registration Session',
+			'event_espresso'
+		);
+
+		$this->_template_args['txn_details']['ip_address']['value'] = isset($this->_session['ip_address'])
+			? $this->_session['ip_address']
+			: '';
+		$this->_template_args['txn_details']['ip_address']['label'] = esc_html__(
+			'Transaction placed from IP',
+			'event_espresso'
+		);
+
+		$this->_template_args['txn_details']['user_agent']['value'] = isset($this->_session['user_agent'])
+			? $this->_session['user_agent']
+			: '';
+		$this->_template_args['txn_details']['user_agent']['label'] = esc_html__(
+			'Registrant User Agent',
+			'event_espresso'
+		);
+
+		$reg_steps = '<ul>';
+		foreach ($this->_transaction->reg_steps() as $reg_step => $reg_step_status) {
+			if ($reg_step_status === true) {
+				$reg_steps .= '<li style="color:#70cc50">'
+							  . sprintf(
+								  esc_html__('%1$s : Completed', 'event_espresso'),
+								  ucwords(str_replace('_', ' ', $reg_step))
+							  )
+							  . '</li>';
+			} elseif (is_numeric($reg_step_status) && $reg_step_status !== false) {
+				$reg_steps .= '<li style="color:#2EA2CC">'
+							  . sprintf(
+								  esc_html__('%1$s : Initiated %2$s', 'event_espresso'),
+								  ucwords(str_replace('_', ' ', $reg_step)),
+								  date(
+									  get_option('date_format') . ' ' . get_option('time_format'),
+									  $reg_step_status + (get_option('gmt_offset') * HOUR_IN_SECONDS)
+								  )
+							  )
+							  . '</li>';
+			} else {
+				$reg_steps .= '<li style="color:#E76700">'
+							  . sprintf(
+								  esc_html__('%1$s : Never Initiated', 'event_espresso'),
+								  ucwords(str_replace('_', ' ', $reg_step))
+							  )
+							  . '</li>';
+			}
+		}
+		$reg_steps .= '</ul>';
+		$this->_template_args['txn_details']['reg_steps']['value'] = $reg_steps;
+		$this->_template_args['txn_details']['reg_steps']['label'] = esc_html__(
+			'Registration Step Progress',
+			'event_espresso'
+		);
+
+
+		$this->_get_registrations_to_apply_payment_to();
+		$this->_get_payment_methods($payments);
+		$this->_get_payment_status_array();
+		$this->_get_reg_status_selection(); // sets up the template args for the reg status array for the transaction.
+
+		$this->_template_args['transaction_form_url'] = add_query_arg(
+			array(
+				'action'  => 'edit_transaction',
+				'process' => 'transaction',
+			),
+			TXN_ADMIN_URL
+		);
+		$this->_template_args['apply_payment_form_url'] = add_query_arg(
+			array(
+				'page'   => 'espresso_transactions',
+				'action' => 'espresso_apply_payment',
+			),
+			WP_AJAX_URL
+		);
+		$this->_template_args['delete_payment_form_url'] = add_query_arg(
+			array(
+				'page'   => 'espresso_transactions',
+				'action' => 'espresso_delete_payment',
+			),
+			WP_AJAX_URL
+		);
+
+		$this->_template_args['action_buttons'] = $this->getActionButtons($this->_transaction);
+
+		// 'espresso_delete_payment_nonce'
+
+		$template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_main_meta_box_txn_details.template.php';
+		echo EEH_Template::display_template($template_path, $this->_template_args, true);
+	}
+
+
+	/**
+	 * _get_registration_payment_IDs
+	 *    generates an array of Payment IDs and their corresponding Registration IDs
+	 *
+	 * @access protected
+	 * @param EE_Payment[] $payments
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _get_registration_payment_IDs($payments = array())
+	{
+		$existing_reg_payments = array();
+		// get all reg payments for these payments
+		$reg_payments = EEM_Registration_Payment::instance()->get_all(
+			array(
+				array(
+					'PAY_ID' => array(
+						'IN',
+						array_keys($payments),
+					),
+				),
+			)
+		);
+		if (! empty($reg_payments)) {
+			foreach ($payments as $payment) {
+				if (! $payment instanceof EE_Payment) {
+					continue;
+				} elseif (! isset($existing_reg_payments[ $payment->ID() ])) {
+					$existing_reg_payments[ $payment->ID() ] = array();
+				}
+				foreach ($reg_payments as $reg_payment) {
+					if ($reg_payment instanceof EE_Registration_Payment
+						&& $reg_payment->payment_ID() === $payment->ID()
+					) {
+						$existing_reg_payments[ $payment->ID() ][] = $reg_payment->registration_ID();
+					}
+				}
+			}
+		}
+
+		return $existing_reg_payments;
+	}
+
+
+	/**
+	 * _get_registrations_to_apply_payment_to
+	 *    generates HTML for displaying a series of checkboxes in the admin payment modal window
+	 * which allows the admin to only apply the payment to the specific registrations
+	 *
+	 * @access protected
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _get_registrations_to_apply_payment_to()
+	{
+		// we want any registration with an active status (ie: not deleted or cancelled)
+		$query_params = array(
+			array(
+				'STS_ID' => array(
+					'IN',
+					array(
+						EEM_Registration::status_id_approved,
+						EEM_Registration::status_id_pending_payment,
+						EEM_Registration::status_id_not_approved,
+					),
+				),
+			),
+		);
+		$registrations_to_apply_payment_to = EEH_HTML::br() . EEH_HTML::div(
+			'',
+			'txn-admin-apply-payment-to-registrations-dv',
+			'',
+			'clear: both; margin: 1.5em 0 0; display: none;'
+		);
+		$registrations_to_apply_payment_to .= EEH_HTML::br() . EEH_HTML::div('', '', 'admin-primary-mbox-tbl-wrap');
+		$registrations_to_apply_payment_to .= EEH_HTML::table('', '', 'admin-primary-mbox-tbl');
+		$registrations_to_apply_payment_to .= EEH_HTML::thead(
+			EEH_HTML::tr(
+				EEH_HTML::th(esc_html__('ID', 'event_espresso')) .
+				EEH_HTML::th(esc_html__('Registrant', 'event_espresso')) .
+				EEH_HTML::th(esc_html__('Ticket', 'event_espresso')) .
+				EEH_HTML::th(esc_html__('Event', 'event_espresso')) .
+				EEH_HTML::th(esc_html__('Paid', 'event_espresso'), '', 'txn-admin-payment-paid-td jst-cntr') .
+				EEH_HTML::th(esc_html__('Owing', 'event_espresso'), '', 'txn-admin-payment-owing-td jst-cntr') .
+				EEH_HTML::th(esc_html__('Apply', 'event_espresso'), '', 'jst-cntr')
+			)
+		);
+		$registrations_to_apply_payment_to .= EEH_HTML::tbody();
+		// get registrations for TXN
+		$registrations = $this->_transaction->registrations($query_params);
+		$existing_reg_payments = $this->_template_args['existing_reg_payments'];
+		foreach ($registrations as $registration) {
+			if ($registration instanceof EE_Registration) {
+				$attendee_name = $registration->attendee() instanceof EE_Attendee
+					? $registration->attendee()->full_name()
+					: esc_html__('Unknown Attendee', 'event_espresso');
+				$owing = $registration->final_price() - $registration->paid();
+				$taxable = $registration->ticket()->taxable()
+					? ' <span class="smaller-text lt-grey-text"> ' . esc_html__('+ tax', 'event_espresso') . '</span>'
+					: '';
+				$checked = empty($existing_reg_payments)
+						   || in_array($registration->ID(), $existing_reg_payments, true)
+					? ' checked="checked"'
+					: '';
+				$disabled = $registration->final_price() > 0 ? '' : ' disabled';
+				$registrations_to_apply_payment_to .= EEH_HTML::tr(
+					EEH_HTML::td($registration->ID()) .
+					EEH_HTML::td($attendee_name) .
+					EEH_HTML::td(
+						$registration->ticket()->name() . ' : ' . $registration->ticket()->pretty_price() . $taxable
+					) .
+					EEH_HTML::td($registration->event_name()) .
+					EEH_HTML::td($registration->pretty_paid(), '', 'txn-admin-payment-paid-td jst-cntr') .
+					EEH_HTML::td(
+						EEH_Template::format_currency($owing),
+						'',
+						'txn-admin-payment-owing-td jst-cntr'
+					) .
+					EEH_HTML::td(
+						'<input type="checkbox" value="' . $registration->ID()
+						. '" name="txn_admin_payment[registrations]"'
+						. $checked . $disabled . '>',
+						'',
+						'jst-cntr'
+					),
+					'apply-payment-registration-row-' . $registration->ID()
+				);
+			}
+		}
+		$registrations_to_apply_payment_to .= EEH_HTML::tbodyx();
+		$registrations_to_apply_payment_to .= EEH_HTML::tablex();
+		$registrations_to_apply_payment_to .= EEH_HTML::divx();
+		$registrations_to_apply_payment_to .= EEH_HTML::p(
+			esc_html__(
+				'The payment will only be applied to the registrations that have a check mark in their corresponding check box. Checkboxes for free registrations have been disabled.',
+				'event_espresso'
+			),
+			'',
+			'clear description'
+		);
+		$registrations_to_apply_payment_to .= EEH_HTML::divx();
+		$this->_template_args['registrations_to_apply_payment_to'] = $registrations_to_apply_payment_to;
+	}
+
+
+	/**
+	 * _get_reg_status_selection
+	 *
+	 * @todo   this will need to be adjusted either once MER comes along OR we move default reg status to tickets
+	 *         instead of events.
+	 * @access protected
+	 * @return void
+	 * @throws EE_Error
+	 */
+	protected function _get_reg_status_selection()
+	{
+		// first get all possible statuses
+		$statuses = EEM_Registration::reg_status_array(array(), true);
+		// let's add a "don't change" option.
+		$status_array['NAN'] = esc_html__('Leave the Same', 'event_espresso');
+		$status_array = array_merge($status_array, $statuses);
+		$this->_template_args['status_change_select'] = EEH_Form_Fields::select_input(
+			'txn_reg_status_change[reg_status]',
+			$status_array,
+			'NAN',
+			'id="txn-admin-payment-reg-status-inp"',
+			'txn-reg-status-change-reg-status'
+		);
+		$this->_template_args['delete_status_change_select'] = EEH_Form_Fields::select_input(
+			'delete_txn_reg_status_change[reg_status]',
+			$status_array,
+			'NAN',
+			'delete-txn-admin-payment-reg-status-inp',
+			'delete-txn-reg-status-change-reg-status'
+		);
+	}
+
+
+	/**
+	 *    _get_payment_methods
+	 * Gets all the payment methods available generally, or the ones that are already
+	 * selected on these payments (in case their payment methods are no longer active).
+	 * Has the side-effect of updating the template args' payment_methods item
+	 *
+	 * @access private
+	 * @param EE_Payment[] to show on this page
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	private function _get_payment_methods($payments = array())
+	{
+		$payment_methods_of_payments = array();
+		foreach ($payments as $payment) {
+			if ($payment instanceof EE_Payment) {
+				$payment_methods_of_payments[] = $payment->ID();
+			}
+		}
+		if ($payment_methods_of_payments) {
+			$query_args = array(
+				array(
+					'OR*payment_method_for_payment' => array(
+						'PMD_ID'    => array('IN', $payment_methods_of_payments),
+						'PMD_scope' => array('LIKE', '%' . EEM_Payment_Method::scope_admin . '%'),
+					),
+				),
+			);
+		} else {
+			$query_args = array(array('PMD_scope' => array('LIKE', '%' . EEM_Payment_Method::scope_admin . '%')));
+		}
+		$this->_template_args['payment_methods'] = EEM_Payment_Method::instance()->get_all($query_args);
+	}
+
+
+	/**
+	 * txn_attendees_meta_box
+	 *    generates HTML for the Attendees Transaction main meta box
+	 *
+	 * @access public
+	 * @param WP_Post $post
+	 * @param array   $metabox
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function txn_attendees_meta_box($post, $metabox = array('args' => array()))
+	{
+
+		/** @noinspection NonSecureExtractUsageInspection */
+		extract($metabox['args']);
+		$this->_template_args['post'] = $post;
+		$this->_template_args['event_attendees'] = array();
+		// process items in cart
+		$line_items = $this->_transaction->get_many_related(
+			'Line_Item',
+			array(array('LIN_type' => 'line-item'))
+		);
+		if (! empty($line_items)) {
+			foreach ($line_items as $item) {
+				if ($item instanceof EE_Line_Item) {
+					switch ($item->OBJ_type()) {
+						case 'Event':
+							break;
+						case 'Ticket':
+							$ticket = $item->ticket();
+							// right now we're only handling tickets here.
+							// Cause its expected that only tickets will have attendees right?
+							if (! $ticket instanceof EE_Ticket) {
+								break;
+							}
+							try {
+								$event_name = $ticket->get_event_name();
+							} catch (Exception $e) {
+								EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
+								$event_name = esc_html__('Unknown Event', 'event_espresso');
+							}
+							$event_name .= ' - ' . $item->name();
+							$ticket_price = EEH_Template::format_currency($item->unit_price());
+							// now get all of the registrations for this transaction that use this ticket
+							$registrations = $ticket->registrations(
+								array(array('TXN_ID' => $this->_transaction->ID()))
+							);
+							foreach ($registrations as $registration) {
+								if (! $registration instanceof EE_Registration) {
+									break;
+								}
+								$this->_template_args['event_attendees'][ $registration->ID() ]['STS_ID']
+									= $registration->status_ID();
+								$this->_template_args['event_attendees'][ $registration->ID() ]['att_num']
+									= $registration->count();
+								$this->_template_args['event_attendees'][ $registration->ID() ]['event_ticket_name']
+									= $event_name;
+								$this->_template_args['event_attendees'][ $registration->ID() ]['ticket_price']
+									= $ticket_price;
+								// attendee info
+								$attendee = $registration->get_first_related('Attendee');
+								if ($attendee instanceof EE_Attendee) {
+									$this->_template_args['event_attendees'][ $registration->ID() ]['att_id']
+										= $attendee->ID();
+									$this->_template_args['event_attendees'][ $registration->ID() ]['attendee']
+										= $attendee->full_name();
+									$this->_template_args['event_attendees'][ $registration->ID() ]['email']
+										= '<a href="mailto:' . $attendee->email() . '?subject=' . $event_name
+										  . esc_html__(
+											  ' Event',
+											  'event_espresso'
+										  )
+										  . '">' . $attendee->email() . '</a>';
+									$this->_template_args['event_attendees'][ $registration->ID() ]['address']
+										= EEH_Address::format($attendee, 'inline', false, false);
+								} else {
+									$this->_template_args['event_attendees'][ $registration->ID() ]['att_id'] = '';
+									$this->_template_args['event_attendees'][ $registration->ID() ]['attendee'] = '';
+									$this->_template_args['event_attendees'][ $registration->ID() ]['email'] = '';
+									$this->_template_args['event_attendees'][ $registration->ID() ]['address'] = '';
+								}
+							}
+							break;
+					}
+				}
+			}
+
+			$this->_template_args['transaction_form_url'] = add_query_arg(
+				array(
+					'action'  => 'edit_transaction',
+					'process' => 'attendees',
+				),
+				TXN_ADMIN_URL
+			);
+			echo EEH_Template::display_template(
+				TXN_TEMPLATE_PATH . 'txn_admin_details_main_meta_box_attendees.template.php',
+				$this->_template_args,
+				true
+			);
+		} else {
+			echo sprintf(
+				esc_html__(
+					'%1$sFor some reason, there are no attendees registered for this transaction. Likely the registration was abandoned in process.%2$s',
+					'event_espresso'
+				),
+				'<p class="important-notice">',
+				'</p>'
+			);
+		}
+	}
+
+
+	/**
+	 * txn_registrant_side_meta_box
+	 * generates HTML for the Edit Transaction side meta box
+	 *
+	 * @access public
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function txn_registrant_side_meta_box()
+	{
+		$primary_att = $this->_transaction->primary_registration() instanceof EE_Registration
+			? $this->_transaction->primary_registration()->get_first_related('Attendee')
+			: null;
+		if (! $primary_att instanceof EE_Attendee) {
+			$this->_template_args['no_attendee_message'] = esc_html__(
+				'There is no attached contact for this transaction.  The transaction either failed due to an error or was abandoned.',
+				'event_espresso'
+			);
+			$primary_att = EEM_Attendee::instance()->create_default_object();
+		}
+		$this->_template_args['ATT_ID'] = $primary_att->ID();
+		$this->_template_args['prime_reg_fname'] = $primary_att->fname();
+		$this->_template_args['prime_reg_lname'] = $primary_att->lname();
+		$this->_template_args['prime_reg_email'] = $primary_att->email();
+		$this->_template_args['prime_reg_phone'] = $primary_att->phone();
+		$this->_template_args['edit_attendee_url'] = EE_Admin_Page::add_query_args_and_nonce(
+			array(
+				'action' => 'edit_attendee',
+				'post'   => $primary_att->ID(),
+			),
+			REG_ADMIN_URL
+		);
+		// get formatted address for registrant
+		$this->_template_args['formatted_address'] = EEH_Address::format($primary_att);
+		echo EEH_Template::display_template(
+			TXN_TEMPLATE_PATH . 'txn_admin_details_side_meta_box_registrant.template.php',
+			$this->_template_args,
+			true
+		);
+	}
+
+
+	/**
+	 * txn_billing_info_side_meta_box
+	 *    generates HTML for the Edit Transaction side meta box
+	 *
+	 * @access public
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 */
+	public function txn_billing_info_side_meta_box()
+	{
+
+		$this->_template_args['billing_form'] = $this->_transaction->billing_info();
+		$this->_template_args['billing_form_url'] = add_query_arg(
+			array('action' => 'edit_transaction', 'process' => 'billing'),
+			TXN_ADMIN_URL
+		);
+
+		$template_path = TXN_TEMPLATE_PATH . 'txn_admin_details_side_meta_box_billing_info.template.php';
+		echo EEH_Template::display_template($template_path, $this->_template_args, true);
+	}
+
+
+	/**
+	 * apply_payments_or_refunds
+	 *    registers a payment or refund made towards a transaction
+	 *
+	 * @access public
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function apply_payments_or_refunds()
+	{
+		$json_response_data = array('return_data' => false);
+		$valid_data = $this->_validate_payment_request_data();
+		$has_access = EE_Registry::instance()->CAP->current_user_can(
+			'ee_edit_payments',
+			'apply_payment_or_refund_from_registration_details'
+		);
+		if (! empty($valid_data) && $has_access) {
+			$PAY_ID = $valid_data['PAY_ID'];
+			// save  the new payment
+			$payment = $this->_create_payment_from_request_data($valid_data);
+			// get the TXN for this payment
+			$transaction = $payment->transaction();
+			// verify transaction
+			if ($transaction instanceof EE_Transaction) {
+				// calculate_total_payments_and_update_status
+				$this->_process_transaction_payments($transaction);
+				$REG_IDs = $this->_get_REG_IDs_to_apply_payment_to($payment);
+				$this->_remove_existing_registration_payments($payment, $PAY_ID);
+				// apply payment to registrations (if applicable)
+				if (! empty($REG_IDs)) {
+					$this->_update_registration_payments($transaction, $payment, $REG_IDs);
+					$this->_maybe_send_notifications();
+					// now process status changes for the same registrations
+					$this->_process_registration_status_change($transaction, $REG_IDs);
+				}
+				$this->_maybe_send_notifications($payment);
+				// prepare to render page
+				$json_response_data['return_data'] = $this->_build_payment_json_response($payment, $REG_IDs);
+				do_action(
+					'AHEE__Transactions_Admin_Page__apply_payments_or_refund__after_recording',
+					$transaction,
+					$payment
+				);
+			} else {
+				EE_Error::add_error(
+					esc_html__(
+						'A valid Transaction for this payment could not be retrieved.',
+						'event_espresso'
+					),
+					__FILE__,
+					__FUNCTION__,
+					__LINE__
+				);
+			}
+		} elseif ($has_access) {
+			EE_Error::add_error(
+				esc_html__(
+					'The payment form data could not be processed. Please try again.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		} else {
+			EE_Error::add_error(
+				esc_html__(
+					'You do not have access to apply payments or refunds to a registration.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		}
+		$notices = EE_Error::get_notices(
+			false,
+			false,
+			false
+		);
+		$this->_template_args = array(
+			'data'    => $json_response_data,
+			'error'   => $notices['errors'],
+			'success' => $notices['success'],
+		);
+		$this->_return_json();
+	}
+
+
+	/**
+	 * _validate_payment_request_data
+	 *
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _validate_payment_request_data()
+	{
+		if (! isset($this->_req_data['txn_admin_payment'])) {
+			return array();
+		}
+		$payment_form = $this->_generate_payment_form_section();
+		try {
+			if ($payment_form->was_submitted()) {
+				$payment_form->receive_form_submission();
+				if (! $payment_form->is_valid()) {
+					$submission_error_messages = array();
+					foreach ($payment_form->get_validation_errors_accumulated() as $validation_error) {
+						if ($validation_error instanceof EE_Validation_Error) {
+							$submission_error_messages[] = sprintf(
+								_x('%s : %s', 'Form Section Name : Form Validation Error', 'event_espresso'),
+								$validation_error->get_form_section()->html_label_text(),
+								$validation_error->getMessage()
+							);
+						}
+					}
+					EE_Error::add_error(
+						implode('<br />', $submission_error_messages),
+						__FILE__,
+						__FUNCTION__,
+						__LINE__
+					);
+					return array();
+				}
+			}
+		} catch (EE_Error $e) {
+			EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
+			return array();
+		}
+
+		return $payment_form->valid_data();
+	}
+
+
+	/**
+	 * _generate_payment_form_section
+	 *
+	 * @return EE_Form_Section_Proper
+	 * @throws EE_Error
+	 */
+	protected function _generate_payment_form_section()
+	{
+		return new EE_Form_Section_Proper(
+			array(
+				'name'        => 'txn_admin_payment',
+				'subsections' => array(
+					'PAY_ID'          => new EE_Text_Input(
+						array(
+							'default'               => 0,
+							'required'              => false,
+							'html_label_text'       => esc_html__('Payment ID', 'event_espresso'),
+							'validation_strategies' => array(new EE_Int_Normalization()),
+						)
+					),
+					'TXN_ID'          => new EE_Text_Input(
+						array(
+							'default'               => 0,
+							'required'              => true,
+							'html_label_text'       => esc_html__('Transaction ID', 'event_espresso'),
+							'validation_strategies' => array(new EE_Int_Normalization()),
+						)
+					),
+					'type'            => new EE_Text_Input(
+						array(
+							'default'               => 1,
+							'required'              => true,
+							'html_label_text'       => esc_html__('Payment or Refund', 'event_espresso'),
+							'validation_strategies' => array(new EE_Int_Normalization()),
+						)
+					),
+					'amount'          => new EE_Text_Input(
+						array(
+							'default'               => 0,
+							'required'              => true,
+							'html_label_text'       => esc_html__('Payment amount', 'event_espresso'),
+							'validation_strategies' => array(new EE_Float_Normalization()),
+						)
+					),
+					'status'          => new EE_Text_Input(
+						array(
+							'default'         => EEM_Payment::status_id_approved,
+							'required'        => true,
+							'html_label_text' => esc_html__('Payment status', 'event_espresso'),
+						)
+					),
+					'PMD_ID'          => new EE_Text_Input(
+						array(
+							'default'               => 2,
+							'required'              => true,
+							'html_label_text'       => esc_html__('Payment Method', 'event_espresso'),
+							'validation_strategies' => array(new EE_Int_Normalization()),
+						)
+					),
+					'date'            => new EE_Text_Input(
+						array(
+							'default'         => time(),
+							'required'        => true,
+							'html_label_text' => esc_html__('Payment date', 'event_espresso'),
+						)
+					),
+					'txn_id_chq_nmbr' => new EE_Text_Input(
+						array(
+							'default'               => '',
+							'required'              => false,
+							'html_label_text'       => esc_html__('Transaction or Cheque Number', 'event_espresso'),
+							'validation_strategies' => array(
+								new EE_Max_Length_Validation_Strategy(
+									esc_html__('Input too long', 'event_espresso'),
+									100
+								),
+							),
+						)
+					),
+					'po_number'       => new EE_Text_Input(
+						array(
+							'default'               => '',
+							'required'              => false,
+							'html_label_text'       => esc_html__('Purchase Order Number', 'event_espresso'),
+							'validation_strategies' => array(
+								new EE_Max_Length_Validation_Strategy(
+									esc_html__('Input too long', 'event_espresso'),
+									100
+								),
+							),
+						)
+					),
+					'accounting'      => new EE_Text_Input(
+						array(
+							'default'               => '',
+							'required'              => false,
+							'html_label_text'       => esc_html__('Extra Field for Accounting', 'event_espresso'),
+							'validation_strategies' => array(
+								new EE_Max_Length_Validation_Strategy(
+									esc_html__('Input too long', 'event_espresso'),
+									100
+								),
+							),
+						)
+					),
+				),
+			)
+		);
+	}
+
+
+	/**
+	 * _create_payment_from_request_data
+	 *
+	 * @param array $valid_data
+	 * @return EE_Payment
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _create_payment_from_request_data($valid_data)
+	{
+		$PAY_ID = $valid_data['PAY_ID'];
+		// get payment amount
+		$amount = $valid_data['amount'] ? abs($valid_data['amount']) : 0;
+		// payments have a type value of 1 and refunds have a type value of -1
+		// so multiplying amount by type will give a positive value for payments, and negative values for refunds
+		$amount = $valid_data['type'] < 0 ? $amount * -1 : $amount;
+		// for some reason the date string coming in has extra spaces between the date and time.  This fixes that.
+		$date = $valid_data['date']
+			? preg_replace('/\s+/', ' ', $valid_data['date'])
+			: date('Y-m-d g:i a', current_time('timestamp'));
+		$payment = EE_Payment::new_instance(
+			array(
+				'TXN_ID'              => $valid_data['TXN_ID'],
+				'STS_ID'              => $valid_data['status'],
+				'PAY_timestamp'       => $date,
+				'PAY_source'          => EEM_Payment_Method::scope_admin,
+				'PMD_ID'              => $valid_data['PMD_ID'],
+				'PAY_amount'          => $amount,
+				'PAY_txn_id_chq_nmbr' => $valid_data['txn_id_chq_nmbr'],
+				'PAY_po_number'       => $valid_data['po_number'],
+				'PAY_extra_accntng'   => $valid_data['accounting'],
+				'PAY_details'         => $valid_data,
+				'PAY_ID'              => $PAY_ID,
+			),
+			'',
+			array('Y-m-d', 'g:i a')
+		);
+
+		if (! $payment->save()) {
+			EE_Error::add_error(
+				sprintf(
+					esc_html__('Payment %1$d has not been successfully saved to the database.', 'event_espresso'),
+					$payment->ID()
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		}
+
+		return $payment;
+	}
+
+
+	/**
+	 * _process_transaction_payments
+	 *
+	 * @param \EE_Transaction $transaction
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _process_transaction_payments(EE_Transaction $transaction)
+	{
+		/** @type EE_Transaction_Payments $transaction_payments */
+		$transaction_payments = EE_Registry::instance()->load_class('Transaction_Payments');
+		// update the transaction with this payment
+		if ($transaction_payments->calculate_total_payments_and_update_status($transaction)) {
+			EE_Error::add_success(
+				esc_html__(
+					'The payment has been processed successfully.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		} else {
+			EE_Error::add_error(
+				esc_html__(
+					'The payment was processed successfully but the amount paid for the transaction was not updated.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		}
+	}
+
+
+	/**
+	 * _get_REG_IDs_to_apply_payment_to
+	 * returns a list of registration IDs that the payment will apply to
+	 *
+	 * @param \EE_Payment $payment
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _get_REG_IDs_to_apply_payment_to(EE_Payment $payment)
+	{
+		$REG_IDs = array();
+		// grab array of IDs for specific registrations to apply changes to
+		if (isset($this->_req_data['txn_admin_payment']['registrations'])) {
+			$REG_IDs = (array) $this->_req_data['txn_admin_payment']['registrations'];
+		}
+		// nothing specified ? then get all reg IDs
+		if (empty($REG_IDs)) {
+			$registrations = $payment->transaction()->registrations();
+			$REG_IDs = ! empty($registrations)
+				? array_keys($registrations)
+				: $this->_get_existing_reg_payment_REG_IDs($payment);
+		}
+
+		// ensure that REG_IDs are integers and NOT strings
+		return array_map('intval', $REG_IDs);
+	}
+
+
+	/**
+	 * @return array
+	 */
+	public function existing_reg_payment_REG_IDs()
+	{
+		return $this->_existing_reg_payment_REG_IDs;
+	}
+
+
+	/**
+	 * @param array $existing_reg_payment_REG_IDs
+	 */
+	public function set_existing_reg_payment_REG_IDs($existing_reg_payment_REG_IDs = null)
+	{
+		$this->_existing_reg_payment_REG_IDs = $existing_reg_payment_REG_IDs;
+	}
+
+
+	/**
+	 * _get_existing_reg_payment_REG_IDs
+	 * returns a list of registration IDs that the payment is currently related to
+	 * as recorded in the database
+	 *
+	 * @param \EE_Payment $payment
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _get_existing_reg_payment_REG_IDs(EE_Payment $payment)
+	{
+		if ($this->existing_reg_payment_REG_IDs() === null) {
+			// let's get any existing reg payment records for this payment
+			$existing_reg_payment_REG_IDs = $payment->get_many_related('Registration');
+			// but we only want the REG IDs, so grab the array keys
+			$existing_reg_payment_REG_IDs = ! empty($existing_reg_payment_REG_IDs)
+				? array_keys($existing_reg_payment_REG_IDs)
+				: array();
+			$this->set_existing_reg_payment_REG_IDs($existing_reg_payment_REG_IDs);
+		}
+
+		return $this->existing_reg_payment_REG_IDs();
+	}
+
+
+	/**
+	 * _remove_existing_registration_payments
+	 * this calculates the difference between existing relations
+	 * to the supplied payment and the new list registration IDs,
+	 * removes any related registrations that no longer apply,
+	 * and then updates the registration paid fields
+	 *
+	 * @param \EE_Payment $payment
+	 * @param int         $PAY_ID
+	 * @return bool;
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _remove_existing_registration_payments(EE_Payment $payment, $PAY_ID = 0)
+	{
+		// newly created payments will have nothing recorded for $PAY_ID
+		if (absint($PAY_ID) === 0) {
+			return false;
+		}
+		$existing_reg_payment_REG_IDs = $this->_get_existing_reg_payment_REG_IDs($payment);
+		if (empty($existing_reg_payment_REG_IDs)) {
+			return false;
+		}
+		/** @type EE_Transaction_Payments $transaction_payments */
+		$transaction_payments = EE_Registry::instance()->load_class('Transaction_Payments');
+
+		return $transaction_payments->delete_registration_payments_and_update_registrations(
+			$payment,
+			array(
+				array(
+					'PAY_ID' => $payment->ID(),
+					'REG_ID' => array('IN', $existing_reg_payment_REG_IDs),
+				),
+			)
+		);
+	}
+
+
+	/**
+	 * _update_registration_payments
+	 * this applies the payments to the selected registrations
+	 * but only if they have not already been paid for
+	 *
+	 * @param  EE_Transaction $transaction
+	 * @param \EE_Payment     $payment
+	 * @param array           $REG_IDs
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _update_registration_payments(
+		EE_Transaction $transaction,
+		EE_Payment $payment,
+		$REG_IDs = array()
+	) {
+		// we can pass our own custom set of registrations to EE_Payment_Processor::process_registration_payments()
+		// so let's do that using our set of REG_IDs from the form
+		$registration_query_where_params = array(
+			'REG_ID' => array('IN', $REG_IDs),
+		);
+		// but add in some conditions regarding payment,
+		// so that we don't apply payments to registrations that are free or have already been paid for
+		// but ONLY if the payment is NOT a refund ( ie: the payment amount is not negative )
+		if (! $payment->is_a_refund()) {
+			$registration_query_where_params['REG_final_price'] = array('!=', 0);
+			$registration_query_where_params['REG_final_price*'] = array('!=', 'REG_paid', true);
+		}
+		$registrations = $transaction->registrations(array($registration_query_where_params));
+		if (! empty($registrations)) {
+			/** @type EE_Payment_Processor $payment_processor */
+			$payment_processor = EE_Registry::instance()->load_core('Payment_Processor');
+			$payment_processor->process_registration_payments($transaction, $payment, $registrations);
+		}
+	}
+
+
+	/**
+	 * _process_registration_status_change
+	 * This processes requested registration status changes for all the registrations
+	 * on a given transaction and (optionally) sends out notifications for the changes.
+	 *
+	 * @param  EE_Transaction $transaction
+	 * @param array           $REG_IDs
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _process_registration_status_change(EE_Transaction $transaction, $REG_IDs = array())
+	{
+		// first if there is no change in status then we get out.
+		if (! isset($this->_req_data['txn_reg_status_change']['reg_status'])
+			|| $this->_req_data['txn_reg_status_change']['reg_status'] === 'NAN'
+		) {
+			// no error message, no change requested, just nothing to do man.
+			return false;
+		}
+		/** @type EE_Transaction_Processor $transaction_processor */
+		$transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
+
+		// made it here dude?  Oh WOW.  K, let's take care of changing the statuses
+		return $transaction_processor->manually_update_registration_statuses(
+			$transaction,
+			sanitize_text_field($this->_req_data['txn_reg_status_change']['reg_status']),
+			array(array('REG_ID' => array('IN', $REG_IDs)))
+		);
+	}
+
+
+	/**
+	 * _build_payment_json_response
+	 *
+	 * @access public
+	 * @param \EE_Payment $payment
+	 * @param array       $REG_IDs
+	 * @param bool | null $delete_txn_reg_status_change
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _build_payment_json_response(
+		EE_Payment $payment,
+		$REG_IDs = array(),
+		$delete_txn_reg_status_change = null
+	) {
+		// was the payment deleted ?
+		if (is_bool($delete_txn_reg_status_change)) {
+			return array(
+				'PAY_ID'                       => $payment->ID(),
+				'amount'                       => $payment->amount(),
+				'total_paid'                   => $payment->transaction()->paid(),
+				'txn_status'                   => $payment->transaction()->status_ID(),
+				'pay_status'                   => $payment->STS_ID(),
+				'registrations'                => $this->_registration_payment_data_array($REG_IDs),
+				'delete_txn_reg_status_change' => $delete_txn_reg_status_change,
+			);
+		} else {
+			$this->_get_payment_status_array();
+
+			return array(
+				'amount'           => $payment->amount(),
+				'total_paid'       => $payment->transaction()->paid(),
+				'txn_status'       => $payment->transaction()->status_ID(),
+				'pay_status'       => $payment->STS_ID(),
+				'PAY_ID'           => $payment->ID(),
+				'STS_ID'           => $payment->STS_ID(),
+				'status'           => self::$_pay_status[ $payment->STS_ID() ],
+				'date'             => $payment->timestamp('Y-m-d', 'h:i a'),
+				'method'           => strtoupper($payment->source()),
+				'PM_ID'            => $payment->payment_method() ? $payment->payment_method()->ID() : 1,
+				'gateway'          => $payment->payment_method()
+					? $payment->payment_method()->admin_name()
+					: esc_html__('Unknown', 'event_espresso'),
+				'gateway_response' => $payment->gateway_response(),
+				'txn_id_chq_nmbr'  => $payment->txn_id_chq_nmbr(),
+				'po_number'        => $payment->po_number(),
+				'extra_accntng'    => $payment->extra_accntng(),
+				'registrations'    => $this->_registration_payment_data_array($REG_IDs),
+			);
+		}
+	}
+
+
+	/**
+	 * delete_payment
+	 *    delete a payment or refund made towards a transaction
+	 *
+	 * @access public
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function delete_payment()
+	{
+		$json_response_data = array('return_data' => false);
+		$PAY_ID = isset($this->_req_data['delete_txn_admin_payment']['PAY_ID'])
+			? absint($this->_req_data['delete_txn_admin_payment']['PAY_ID'])
+			: 0;
+		$can_delete = EE_Registry::instance()->CAP->current_user_can(
+			'ee_delete_payments',
+			'delete_payment_from_registration_details'
+		);
+		if ($PAY_ID && $can_delete) {
+			$delete_txn_reg_status_change = isset($this->_req_data['delete_txn_reg_status_change'])
+				? $this->_req_data['delete_txn_reg_status_change']
+				: false;
+			$payment = EEM_Payment::instance()->get_one_by_ID($PAY_ID);
+			if ($payment instanceof EE_Payment) {
+				$REG_IDs = $this->_get_existing_reg_payment_REG_IDs($payment);
+				/** @type EE_Transaction_Payments $transaction_payments */
+				$transaction_payments = EE_Registry::instance()->load_class('Transaction_Payments');
+				if ($transaction_payments->delete_payment_and_update_transaction($payment)) {
+					$json_response_data['return_data'] = $this->_build_payment_json_response(
+						$payment,
+						$REG_IDs,
+						$delete_txn_reg_status_change
+					);
+					if ($delete_txn_reg_status_change) {
+						$this->_req_data['txn_reg_status_change'] = $delete_txn_reg_status_change;
+						// MAKE sure we also add the delete_txn_req_status_change to the
+						// $_REQUEST global because that's how messages will be looking for it.
+						$_REQUEST['txn_reg_status_change'] = $delete_txn_reg_status_change;
+						$this->_maybe_send_notifications();
+						$this->_process_registration_status_change($payment->transaction(), $REG_IDs);
+					}
+				}
+			} else {
+				EE_Error::add_error(
+					esc_html__('Valid Payment data could not be retrieved from the database.', 'event_espresso'),
+					__FILE__,
+					__FUNCTION__,
+					__LINE__
+				);
+			}
+		} elseif ($can_delete) {
+			EE_Error::add_error(
+				esc_html__(
+					'A valid Payment ID was not received, therefore payment form data could not be loaded.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		} else {
+			EE_Error::add_error(
+				esc_html__(
+					'You do not have access to delete a payment.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		}
+		$notices = EE_Error::get_notices(false, false, false);
+		$this->_template_args = array(
+			'data'      => $json_response_data,
+			'success'   => $notices['success'],
+			'error'     => $notices['errors'],
+			'attention' => $notices['attention'],
+		);
+		$this->_return_json();
+	}
+
+
+	/**
+	 * _registration_payment_data_array
+	 * adds info for 'owing' and 'paid' for each registration to the json response
+	 *
+	 * @access protected
+	 * @param array $REG_IDs
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _registration_payment_data_array($REG_IDs)
+	{
+		$registration_payment_data = array();
+		// if non empty reg_ids lets get an array of registrations and update the values for the apply_payment/refund rows.
+		if (! empty($REG_IDs)) {
+			$registrations = EEM_Registration::instance()->get_all(array(array('REG_ID' => array('IN', $REG_IDs))));
+			foreach ($registrations as $registration) {
+				if ($registration instanceof EE_Registration) {
+					$registration_payment_data[ $registration->ID() ] = array(
+						'paid'  => $registration->pretty_paid(),
+						'owing' => EEH_Template::format_currency($registration->final_price() - $registration->paid()),
+					);
+				}
+			}
+		}
+
+		return $registration_payment_data;
+	}
+
+
+	/**
+	 * _maybe_send_notifications
+	 * determines whether or not the admin has indicated that notifications should be sent.
+	 * If so, will toggle a filter switch for delivering registration notices.
+	 * If passed an EE_Payment object, then it will trigger payment notifications instead.
+	 *
+	 * @access protected
+	 * @param \EE_Payment | null $payment
+	 */
+	protected function _maybe_send_notifications($payment = null)
+	{
+		switch ($payment instanceof EE_Payment) {
+			// payment notifications
+			case true:
+				if (isset($this->_req_data['txn_payments']['send_notifications'])
+					&& filter_var(
+						$this->_req_data['txn_payments']['send_notifications'],
+						FILTER_VALIDATE_BOOLEAN
+					)
+				) {
+					$this->_process_payment_notification($payment);
+				}
+				break;
+			// registration notifications
+			case false:
+				if (isset($this->_req_data['txn_reg_status_change']['send_notifications'])
+					&& filter_var(
+						$this->_req_data['txn_reg_status_change']['send_notifications'],
+						FILTER_VALIDATE_BOOLEAN
+					)
+				) {
+					add_filter('FHEE__EED_Messages___maybe_registration__deliver_notifications', '__return_true');
+				}
+				break;
+		}
+	}
+
+
+	/**
+	 * _send_payment_reminder
+	 *    generates HTML for the View Transaction Details Admin page
+	 *
+	 * @access protected
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _send_payment_reminder()
+	{
+		$TXN_ID = ! empty($this->_req_data['TXN_ID']) ? absint($this->_req_data['TXN_ID']) : false;
+		$transaction = EEM_Transaction::instance()->get_one_by_ID($TXN_ID);
+		$query_args = isset($this->_req_data['redirect_to']) ? array(
+			'action' => $this->_req_data['redirect_to'],
+			'TXN_ID' => $this->_req_data['TXN_ID'],
+		) : array();
+		do_action(
+			'AHEE__Transactions_Admin_Page___send_payment_reminder__process_admin_payment_reminder',
+			$transaction
+		);
+		$this->_redirect_after_action(
+			false,
+			esc_html__('payment reminder', 'event_espresso'),
+			esc_html__('sent', 'event_espresso'),
+			$query_args,
+			true
+		);
+	}
+
+
+	/**
+	 *  get_transactions
+	 *    get transactions for given parameters (used by list table)
+	 *
+	 * @param  int     $perpage how many transactions displayed per page
+	 * @param  boolean $count   return the count or objects
+	 * @param string   $view
+	 * @return mixed int = count || array of transaction objects
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function get_transactions($perpage, $count = false, $view = '')
+	{
+
+		$TXN = EEM_Transaction::instance();
+
+		$start_date = isset($this->_req_data['txn-filter-start-date'])
+			? wp_strip_all_tags($this->_req_data['txn-filter-start-date'])
+			: date(
+				'm/d/Y',
+				strtotime('-10 year')
+			);
+		$end_date = isset($this->_req_data['txn-filter-end-date'])
+			? wp_strip_all_tags($this->_req_data['txn-filter-end-date'])
+			: date('m/d/Y');
+
+		// make sure our timestamps start and end right at the boundaries for each day
+		$start_date = date('Y-m-d', strtotime($start_date)) . ' 00:00:00';
+		$end_date = date('Y-m-d', strtotime($end_date)) . ' 23:59:59';
+
+
+		// convert to timestamps
+		$start_date = strtotime($start_date);
+		$end_date = strtotime($end_date);
+
+		// makes sure start date is the lowest value and vice versa
+		$start_date = min($start_date, $end_date);
+		$end_date = max($start_date, $end_date);
+
+		// convert to correct format for query
+		$start_date = EEM_Transaction::instance()->convert_datetime_for_query(
+			'TXN_timestamp',
+			date('Y-m-d H:i:s', $start_date),
+			'Y-m-d H:i:s'
+		);
+		$end_date = EEM_Transaction::instance()->convert_datetime_for_query(
+			'TXN_timestamp',
+			date('Y-m-d H:i:s', $end_date),
+			'Y-m-d H:i:s'
+		);
+
+
+		// set orderby
+		$this->_req_data['orderby'] = ! empty($this->_req_data['orderby']) ? $this->_req_data['orderby'] : '';
+
+		switch ($this->_req_data['orderby']) {
+			case 'TXN_ID':
+				$orderby = 'TXN_ID';
+				break;
+			case 'ATT_fname':
+				$orderby = 'Registration.Attendee.ATT_fname';
+				break;
+			case 'event_name':
+				$orderby = 'Registration.Event.EVT_name';
+				break;
+			default: // 'TXN_timestamp'
+				$orderby = 'TXN_timestamp';
+		}
+
+		$sort = ! empty($this->_req_data['order']) ? $this->_req_data['order'] : 'DESC';
+		$current_page = ! empty($this->_req_data['paged']) ? $this->_req_data['paged'] : 1;
+		$per_page = ! empty($perpage) ? $perpage : 10;
+		$per_page = ! empty($this->_req_data['perpage']) ? $this->_req_data['perpage'] : $per_page;
+
+		$offset = ($current_page - 1) * $per_page;
+		$limit = array($offset, $per_page);
+
+		$_where = array(
+			'TXN_timestamp'          => array('BETWEEN', array($start_date, $end_date)),
+			'Registration.REG_count' => 1,
+		);
+
+		if (isset($this->_req_data['EVT_ID'])) {
+			$_where['Registration.EVT_ID'] = $this->_req_data['EVT_ID'];
+		}
+
+		if (isset($this->_req_data['s'])) {
+			$search_string = '%' . $this->_req_data['s'] . '%';
+			$_where['OR'] = array(
+				'Registration.Event.EVT_name'         => array('LIKE', $search_string),
+				'Registration.Event.EVT_desc'         => array('LIKE', $search_string),
+				'Registration.Event.EVT_short_desc'   => array('LIKE', $search_string),
+				'Registration.Attendee.ATT_full_name' => array('LIKE', $search_string),
+				'Registration.Attendee.ATT_fname'     => array('LIKE', $search_string),
+				'Registration.Attendee.ATT_lname'     => array('LIKE', $search_string),
+				'Registration.Attendee.ATT_short_bio' => array('LIKE', $search_string),
+				'Registration.Attendee.ATT_email'     => array('LIKE', $search_string),
+				'Registration.Attendee.ATT_address'   => array('LIKE', $search_string),
+				'Registration.Attendee.ATT_address2'  => array('LIKE', $search_string),
+				'Registration.Attendee.ATT_city'      => array('LIKE', $search_string),
+				'Registration.REG_final_price'        => array('LIKE', $search_string),
+				'Registration.REG_code'               => array('LIKE', $search_string),
+				'Registration.REG_count'              => array('LIKE', $search_string),
+				'Registration.REG_group_size'         => array('LIKE', $search_string),
+				'Registration.Ticket.TKT_name'        => array('LIKE', $search_string),
+				'Registration.Ticket.TKT_description' => array('LIKE', $search_string),
+				'Payment.PAY_source'                  => array('LIKE', $search_string),
+				'Payment.Payment_Method.PMD_name'     => array('LIKE', $search_string),
+				'TXN_session_data'                    => array('LIKE', $search_string),
+				'Payment.PAY_txn_id_chq_nmbr'         => array('LIKE', $search_string),
+			);
+		}
+
+		// failed transactions
+		$failed = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'failed' && ! $count)
+				  || ($count && $view === 'failed');
+		$abandoned = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'abandoned' && ! $count)
+					 || ($count && $view === 'abandoned');
+		$incomplete = (! empty($this->_req_data['status']) && $this->_req_data['status'] === 'incomplete' && ! $count)
+					  || ($count && $view === 'incomplete');
+
+		if ($failed) {
+			$_where['STS_ID'] = EEM_Transaction::failed_status_code;
+		} elseif ($abandoned) {
+			$_where['STS_ID'] = EEM_Transaction::abandoned_status_code;
+		} elseif ($incomplete) {
+			$_where['STS_ID'] = EEM_Transaction::incomplete_status_code;
+		} else {
+			$_where['STS_ID'] = array('!=', EEM_Transaction::failed_status_code);
+			$_where['STS_ID*'] = array('!=', EEM_Transaction::abandoned_status_code);
+		}
+
+		$query_params = apply_filters(
+			'FHEE__Transactions_Admin_Page___get_transactions_query_params',
+			array(
+				$_where,
+				'order_by'                 => array($orderby => $sort),
+				'limit'                    => $limit,
+				'default_where_conditions' => EEM_Base::default_where_conditions_this_only,
+			),
+			$this->_req_data,
+			$view,
+			$count
+		);
+
+		$transactions = $count
+			? $TXN->count(array($query_params[0]), 'TXN_ID', true)
+			: $TXN->get_all($query_params);
+
+		return $transactions;
+	}
+
+
+	/**
+	 * @since $VID:$
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	public function recalculateLineItems()
+	{
+		$TXN_ID = ! empty($this->_req_data['TXN_ID']) ? absint($this->_req_data['TXN_ID']) : false;
+		/** @var EE_Transaction $transaction */
+		$transaction = EEM_Transaction::instance()->get_one_by_ID($TXN_ID);
+		$total_line_item = $transaction->total_line_item(false);
+		$success = false;
+		if ($total_line_item instanceof EE_Line_Item) {
+			EEH_Line_Item::resetIsTaxableForTickets($total_line_item);
+			$success = EEH_Line_Item::apply_taxes($total_line_item, true);
+		}
+		$this->_redirect_after_action(
+			(bool) $success,
+			esc_html__('Transaction taxes and totals', 'event_espresso'),
+			esc_html__('recalculated', 'event_espresso'),
+			isset($this->_req_data['redirect_to'])
+				? array(
+				'action' => $this->_req_data['redirect_to'],
+				'TXN_ID' => $this->_req_data['TXN_ID'],
+			)
+				: array(),
+			true
+		);
+	}
 }

core/db_classes/EE_Transaction.class.php

Doc Comments +3 added lines, -3 removed lines

@@ -366,7 +366,7 @@ 
 
 
     /**
-     * @return mixed|null
+     * @return EE_Cart|null
      * @throws EE_Error
      * @throws InvalidArgumentException
      * @throws InvalidDataTypeException
@@ -508,7 +508,7 @@ 
      * Gets all the attendees for this transaction (handy for use with EE_Attendee's get_registrations_for_event
      * function for getting attendees and how many registrations they each have for an event)
      *
-     * @return mixed EE_Attendee[] by default, int if $output is set to 'COUNT'
+     * @return EE_Base_Class[] EE_Attendee[] by default, int if $output is set to 'COUNT'
      * @throws EE_Error
      * @throws InvalidArgumentException
      * @throws InvalidDataTypeException
@@ -564,7 +564,7 @@ 
     /**
      * Gets all payments which have not been approved
      *
-     * @return EE_Base_Class[]|EEI_Payment[]
+     * @return EE_Base_Class[]
      * @throws EE_Error if a model is misconfigured somehow
      * @throws InvalidArgumentException
      * @throws InvalidDataTypeException

Indentation +1678 added lines, -1678 removed lines

@@ -13,1682 +13,1682 @@
 class EE_Transaction extends EE_Base_Class implements EEI_Transaction
 {
 
-    /**
-     * The length of time in seconds that a lock is applied before being considered expired.
-     * It is not long because a transaction should only be locked for the duration of the request that locked it
-     */
-    const LOCK_EXPIRATION = 2;
-
-    /**
-     * txn status upon initial construction.
-     *
-     * @var string
-     */
-    protected $_old_txn_status;
-
-
-    /**
-     * @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  $date_formats            incoming date_formats in an array where the first value is the
-     *                                        date_format and the second value is the time format
-     * @return EE_Transaction
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function new_instance($props_n_values = array(), $timezone = null, $date_formats = array())
-    {
-        $has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
-        $txn = $has_object
-            ? $has_object
-            : new self($props_n_values, false, $timezone, $date_formats);
-        if (! $has_object) {
-            $txn->set_old_txn_status($txn->status_ID());
-        }
-        return $txn;
-    }
-
-
-    /**
-     * @param array  $props_n_values  incoming values from the database
-     * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
-     *                                the website will be used.
-     * @return EE_Transaction
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function new_instance_from_db($props_n_values = array(), $timezone = null)
-    {
-        $txn = new self($props_n_values, true, $timezone);
-        $txn->set_old_txn_status($txn->status_ID());
-        return $txn;
-    }
-
-
-    /**
-     * Sets a meta field indicating that this TXN is locked and should not be updated in the db.
-     * If a lock has already been set, then we will attempt to remove it in case it has expired.
-     * If that also fails, then an exception is thrown.
-     *
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function lock()
-    {
-        // attempt to set lock, but if that fails...
-        if (! $this->add_extra_meta('lock', time(), true)) {
-            // then attempt to remove the lock in case it is expired
-            if ($this->_remove_expired_lock()) {
-                // if removal was successful, then try setting lock again
-                $this->lock();
-            } else {
-                // but if the lock can not be removed, then throw an exception
-                throw new EE_Error(
-                    sprintf(
-                        __(
-                            'Could not lock Transaction %1$d because it is already locked, meaning another part of the system is currently editing it. It should already be unlocked by the time you read this, so please refresh the page and try again.',
-                            'event_espresso'
-                        ),
-                        $this->ID()
-                    )
-                );
-            }
-        }
-    }
-
-
-    /**
-     * removes transaction lock applied in EE_Transaction::lock()
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function unlock()
-    {
-        return $this->delete_extra_meta('lock');
-    }
-
-
-    /**
-     * Decides whether or not now is the right time to update the transaction.
-     * This is useful because we don't always know if it is safe to update the transaction
-     * and its related data. why?
-     * because it's possible that the transaction is being used in another
-     * request and could overwrite anything we save.
-     * So we want to only update the txn once we know that won't happen.
-     * We also check that the lock isn't expired, and remove it if it is
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_locked()
-    {
-        // if TXN is not locked, then return false immediately
-        if (! $this->_get_lock()) {
-            return false;
-        }
-        // if not, then let's try and remove the lock in case it's expired...
-        // _remove_expired_lock() returns 0 when lock is valid (ie: removed = false)
-        // and a positive number if the lock was removed (ie: number of locks deleted),
-        // so we need to return the opposite
-        return ! $this->_remove_expired_lock() ? true : false;
-    }
-
-
-    /**
-     * Gets the meta field indicating that this TXN is locked
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _get_lock()
-    {
-        return (int) $this->get_extra_meta('lock', true, 0);
-    }
-
-
-    /**
-     * If the lock on this transaction is expired, then we want to remove it so that the transaction can be updated
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _remove_expired_lock()
-    {
-        $locked = $this->_get_lock();
-        if ($locked && time() - EE_Transaction::LOCK_EXPIRATION > $locked) {
-            return $this->unlock();
-        }
-        return 0;
-    }
-
-
-    /**
-     * Set transaction total
-     *
-     * @param float $total total value of transaction
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_total($total = 0.00)
-    {
-        $this->set('TXN_total', (float) $total);
-    }
-
-
-    /**
-     * Set Total Amount Paid to Date
-     *
-     * @param float $total_paid total amount paid to date (sum of all payments)
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_paid($total_paid = 0.00)
-    {
-        $this->set('TXN_paid', (float) $total_paid);
-    }
-
-
-    /**
-     * Set transaction status
-     *
-     * @param string $status        whether the transaction is open, declined, accepted,
-     *                              or any number of custom values that can be set
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_status($status = '')
-    {
-        $this->set('STS_ID', $status);
-    }
-
-
-    /**
-     * Set hash salt
-     *
-     * @param string $hash_salt required for some payment gateways
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_hash_salt($hash_salt = '')
-    {
-        $this->set('TXN_hash_salt', $hash_salt);
-    }
-
-
-    /**
-     * Sets TXN_reg_steps array
-     *
-     * @param array $txn_reg_steps
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_reg_steps(array $txn_reg_steps)
-    {
-        $this->set('TXN_reg_steps', $txn_reg_steps);
-    }
-
-
-    /**
-     * Gets TXN_reg_steps
-     *
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function reg_steps()
-    {
-        $TXN_reg_steps = $this->get('TXN_reg_steps');
-        return is_array($TXN_reg_steps) ? (array) $TXN_reg_steps : array();
-    }
-
-
-    /**
-     * @return string of transaction's total cost, with currency symbol and decimal
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretty_total()
-    {
-        return $this->get_pretty('TXN_total');
-    }
-
-
-    /**
-     * Gets the amount paid in a pretty string (formatted and with currency symbol)
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretty_paid()
-    {
-        return $this->get_pretty('TXN_paid');
-    }
-
-
-    /**
-     * calculate the amount remaining for this transaction and return;
-     *
-     * @return float amount remaining
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function remaining()
-    {
-        return $this->total() - $this->paid();
-    }
-
-
-    /**
-     * get Transaction Total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function total()
-    {
-        return (float) $this->get('TXN_total');
-    }
-
-
-    /**
-     * get Total Amount Paid to Date
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function paid()
-    {
-        return (float) $this->get('TXN_paid');
-    }
-
-
-    /**
-     * @return mixed|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_cart_session()
-    {
-        $session_data = (array) $this->get('TXN_session_data');
-        return isset($session_data['cart']) && $session_data['cart'] instanceof EE_Cart
-            ? $session_data['cart']
-            : null;
-    }
-
-
-    /**
-     * get Transaction session data
-     *
-     * @return array|mixed
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function session_data()
-    {
-        $session_data = $this->get('TXN_session_data');
-        if (empty($session_data)) {
-            $session_data = array(
-                'id'            => null,
-                'user_id'       => null,
-                'ip_address'    => null,
-                'user_agent'    => null,
-                'init_access'   => null,
-                'last_access'   => null,
-                'pages_visited' => array(),
-            );
-        }
-        return $session_data;
-    }
-
-
-    /**
-     * Set session data within the TXN object
-     *
-     * @param EE_Session|array $session_data
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_txn_session_data($session_data)
-    {
-        if ($session_data instanceof EE_Session) {
-            $this->set('TXN_session_data', $session_data->get_session_data(null, true));
-        } else {
-            $this->set('TXN_session_data', $session_data);
-        }
-    }
-
-
-    /**
-     * get Transaction hash salt
-     *
-     * @return mixed
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function hash_salt_()
-    {
-        return $this->get('TXN_hash_salt');
-    }
-
-
-    /**
-     * Returns the transaction datetime as either:
-     *            - unix timestamp format ($format = false, $gmt = true)
-     *            - formatted date string including the UTC (timezone) offset ($format = true ($gmt
-     *              has no affect with this option)), this also may include a timezone abbreviation if the
-     *              set timezone in this class differs from what the timezone is on the blog.
-     *            - formatted date string including the UTC (timezone) offset (default).
-     *
-     * @param boolean $format   - whether to return a unix timestamp (default) or formatted date string
-     * @param boolean $gmt      - whether to return a unix timestamp with UTC offset applied (default)
-     *                          or no UTC offset applied
-     * @return string | int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function datetime($format = false, $gmt = false)
-    {
-        if ($format) {
-            return $this->get_pretty('TXN_timestamp');
-        }
-        if ($gmt) {
-            return $this->get_raw('TXN_timestamp');
-        }
-        return $this->get('TXN_timestamp');
-    }
-
-
-    /**
-     * Gets registrations on this transaction
-     *
-     * @param array   $query_params array of query parameters
-     * @param boolean $get_cached   TRUE to retrieve cached registrations or FALSE to pull from the db
-     * @return EE_Base_Class[]|EE_Registration[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function registrations($query_params = array(), $get_cached = false)
-    {
-        $query_params = (empty($query_params) || ! is_array($query_params))
-            ? array(
-                'order_by' => array(
-                    'Event.EVT_name'     => 'ASC',
-                    'Attendee.ATT_lname' => 'ASC',
-                    'Attendee.ATT_fname' => 'ASC',
-                ),
-            )
-            : $query_params;
-        $query_params = $get_cached ? array() : $query_params;
-        return $this->get_many_related('Registration', $query_params);
-    }
-
-
-    /**
-     * Gets all the attendees for this transaction (handy for use with EE_Attendee's get_registrations_for_event
-     * function for getting attendees and how many registrations they each have for an event)
-     *
-     * @return mixed EE_Attendee[] by default, int if $output is set to 'COUNT'
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function attendees()
-    {
-        return $this->get_many_related('Attendee', array(array('Registration.Transaction.TXN_ID' => $this->ID())));
-    }
-
-
-    /**
-     * Gets payments for this transaction. Unlike other such functions, order by 'DESC' by default
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Base_Class[]|EE_Payment[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function payments($query_params = array())
-    {
-        return $this->get_many_related('Payment', $query_params);
-    }
-
-
-    /**
-     * gets only approved payments for this transaction
-     *
-     * @return EE_Base_Class[]|EE_Payment[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function approved_payments()
-    {
-        EE_Registry::instance()->load_model('Payment');
-        return $this->get_many_related(
-            'Payment',
-            array(
-                array('STS_ID' => EEM_Payment::status_id_approved),
-                'order_by' => array('PAY_timestamp' => 'DESC'),
-            )
-        );
-    }
-
-
-    /**
-     * Gets all payments which have not been approved
-     *
-     * @return EE_Base_Class[]|EEI_Payment[]
-     * @throws EE_Error if a model is misconfigured somehow
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pending_payments()
-    {
-        return $this->get_many_related(
-            'Payment',
-            array(
-                array(
-                    'STS_ID' => EEM_Payment::status_id_pending,
-                ),
-                'order_by' => array(
-                    'PAY_timestamp' => 'DESC',
-                ),
-            )
-        );
-    }
-
-
-    /**
-     * echoes $this->pretty_status()
-     *
-     * @param bool $show_icons
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function e_pretty_status($show_icons = false)
-    {
-        echo $this->pretty_status($show_icons);
-    }
-
-
-    /**
-     * returns a pretty version of the status, good for displaying to users
-     *
-     * @param bool $show_icons
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretty_status($show_icons = false)
-    {
-        $status = EEM_Status::instance()->localized_status(
-            array($this->status_ID() => __('unknown', 'event_espresso')),
-            false,
-            'sentence'
-        );
-        $icon = '';
-        switch ($this->status_ID()) {
-            case EEM_Transaction::complete_status_code:
-                $icon = $show_icons ? '<span class="dashicons dashicons-yes ee-icon-size-24 green-text"></span>' : '';
-                break;
-            case EEM_Transaction::incomplete_status_code:
-                $icon = $show_icons ? '<span class="dashicons dashicons-marker ee-icon-size-16 lt-blue-text"></span>'
-                    : '';
-                break;
-            case EEM_Transaction::abandoned_status_code:
-                $icon = $show_icons ? '<span class="dashicons dashicons-marker ee-icon-size-16 red-text"></span>' : '';
-                break;
-            case EEM_Transaction::failed_status_code:
-                $icon = $show_icons ? '<span class="dashicons dashicons-no ee-icon-size-16 red-text"></span>' : '';
-                break;
-            case EEM_Transaction::overpaid_status_code:
-                $icon = $show_icons ? '<span class="dashicons dashicons-plus ee-icon-size-16 orange-text"></span>' : '';
-                break;
-        }
-        return $icon . $status[ $this->status_ID() ];
-    }
-
-
-    /**
-     * get Transaction Status
-     *
-     * @return mixed
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function status_ID()
-    {
-        return $this->get('STS_ID');
-    }
-
-
-    /**
-     * Returns TRUE or FALSE for whether or not this transaction cost any money
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_free()
-    {
-        return EEH_Money::compare_floats($this->get('TXN_total'), 0, '==');
-    }
-
-
-    /**
-     * Returns whether this transaction is complete
-     * Useful in templates and other logic for deciding if we should ask for another payment...
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_completed()
-    {
-        return $this->status_ID() === EEM_Transaction::complete_status_code;
-    }
-
-
-    /**
-     * Returns whether this transaction is incomplete
-     * Useful in templates and other logic for deciding if we should ask for another payment...
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_incomplete()
-    {
-        return $this->status_ID() === EEM_Transaction::incomplete_status_code;
-    }
-
-
-    /**
-     * Returns whether this transaction is overpaid
-     * Useful in templates and other logic for deciding if monies need to be refunded
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_overpaid()
-    {
-        return $this->status_ID() === EEM_Transaction::overpaid_status_code;
-    }
-
-
-    /**
-     * Returns whether this transaction was abandoned
-     * meaning that the transaction/registration process was somehow interrupted and never completed
-     * but that contact information exists for at least one registrant
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_abandoned()
-    {
-        return $this->status_ID() === EEM_Transaction::abandoned_status_code;
-    }
-
-
-    /**
-     * Returns whether this transaction failed
-     * meaning that the transaction/registration process was somehow interrupted and never completed
-     * and that NO contact information exists for any registrants
-     *
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function failed()
-    {
-        return $this->status_ID() === EEM_Transaction::failed_status_code;
-    }
-
-
-    /**
-     * This returns the url for the invoice of this transaction
-     *
-     * @param string $type 'html' or 'pdf' (default is pdf)
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function invoice_url($type = 'html')
-    {
-        $REG = $this->primary_registration();
-        if (! $REG instanceof EE_Registration) {
-            return '';
-        }
-        return $REG->invoice_url($type);
-    }
-
-
-    /**
-     * Gets the primary registration only
-     *
-     * @return EE_Base_Class|EE_Registration
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function primary_registration()
-    {
-        $registrations = (array) $this->get_many_related(
-            'Registration',
-            array(array('REG_count' => EEM_Registration::PRIMARY_REGISTRANT_COUNT))
-        );
-        foreach ($registrations as $registration) {
-            // valid registration that is NOT cancelled or declined ?
-            if ($registration instanceof EE_Registration
-                && ! in_array($registration->status_ID(), EEM_Registration::closed_reg_statuses(), true)
-            ) {
-                return $registration;
-            }
-        }
-        // nothing valid found, so just return first thing from array of results
-        return reset($registrations);
-    }
-
-
-    /**
-     * Gets the URL for viewing the receipt
-     *
-     * @param string $type 'pdf' or 'html' (default is 'html')
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function receipt_url($type = 'html')
-    {
-        $REG = $this->primary_registration();
-        if (! $REG instanceof EE_Registration) {
-            return '';
-        }
-        return $REG->receipt_url($type);
-    }
-
-
-    /**
-     * Gets the URL of the thank you page with this registration REG_url_link added as
-     * a query parameter
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function payment_overview_url()
-    {
-        $primary_registration = $this->primary_registration();
-        return $primary_registration instanceof EE_Registration ? $primary_registration->payment_overview_url() : false;
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function gateway_response_on_transaction()
-    {
-        $payment = $this->get_first_related('Payment');
-        return $payment instanceof EE_Payment ? $payment->gateway_response() : '';
-    }
-
-
-    /**
-     * Get the status object of this object
-     *
-     * @return EE_Base_Class|EE_Status
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function status_obj()
-    {
-        return $this->get_first_related('Status');
-    }
-
-
-    /**
-     * Gets all the extra meta info on this payment
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Base_Class[]|EE_Extra_Meta
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function extra_meta($query_params = array())
-    {
-        return $this->get_many_related('Extra_Meta', $query_params);
-    }
-
-
-    /**
-     * Wrapper for _add_relation_to
-     *
-     * @param EE_Registration $registration
-     * @return EE_Base_Class the relation was added to
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function add_registration(EE_Registration $registration)
-    {
-        return $this->_add_relation_to($registration, 'Registration');
-    }
-
-
-    /**
-     * Removes the given registration from being related (even before saving this transaction).
-     * If an ID/index is provided and this transaction isn't saved yet, removes it from list of cached relations
-     *
-     * @param int $registration_or_id
-     * @return EE_Base_Class that was removed from being related
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function remove_registration_with_id($registration_or_id)
-    {
-        return $this->_remove_relation_to($registration_or_id, 'Registration');
-    }
-
-
-    /**
-     * Gets all the line items which are for ACTUAL items
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function items_purchased()
-    {
-        return $this->line_items(array(array('LIN_type' => EEM_Line_Item::type_line_item)));
-    }
-
-
-    /**
-     * Wrapper for _add_relation_to
-     *
-     * @param EE_Line_Item $line_item
-     * @return EE_Base_Class the relation was added to
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function add_line_item(EE_Line_Item $line_item)
-    {
-        return $this->_add_relation_to($line_item, 'Line_Item');
-    }
-
-
-    /**
-     * Gets ALL the line items related to this transaction (unstructured)
-     *
-     * @param array $query_params
-     * @return EE_Base_Class[]|EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function line_items($query_params = array())
-    {
-        return $this->get_many_related('Line_Item', $query_params);
-    }
-
-
-    /**
-     * Gets all the line items which are taxes on the total
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function tax_items()
-    {
-        return $this->line_items(array(array('LIN_type' => EEM_Line_Item::type_tax)));
-    }
-
-
-    /**
-     * Gets the total line item (which is a parent of all other related line items,
-     * meaning it takes them all into account on its total)
-     *
-     * @param bool $create_if_not_found
-     * @return \EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function total_line_item($create_if_not_found = true)
-    {
-        $item = $this->get_first_related('Line_Item', array(array('LIN_type' => EEM_Line_Item::type_total)));
-        if (! $item && $create_if_not_found) {
-            $item = EEH_Line_Item::create_total_line_item($this);
-        }
-        return $item;
-    }
-
-
-    /**
-     * Returns the total amount of tax on this transaction
-     * (assumes there's only one tax subtotal line item)
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function tax_total()
-    {
-        $tax_line_item = $this->tax_total_line_item();
-        if ($tax_line_item) {
-            return (float) $tax_line_item->total();
-        }
-        return (float) 0;
-    }
-
-
-    /**
-     * Gets the tax subtotal line item (assumes there's only one)
-     *
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function tax_total_line_item()
-    {
-        return EEH_Line_Item::get_taxes_subtotal($this->total_line_item());
-    }
-
-
-    /**
-     * Gets the array of billing info for the gateway and for this transaction's primary registration's attendee.
-     *
-     * @return EE_Form_Section_Proper
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function billing_info()
-    {
-        $payment_method = $this->payment_method();
-        if (! $payment_method) {
-            EE_Error::add_error(
-                __(
-                    'Could not find billing info for transaction because no gateway has been used for it yet',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return null;
-        }
-        $primary_reg = $this->primary_registration();
-        if (! $primary_reg) {
-            EE_Error::add_error(
-                __(
-                    'Cannot get billing info for gateway %s on transaction because no primary registration exists',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return null;
-        }
-        $attendee = $primary_reg->attendee();
-        if (! $attendee) {
-            EE_Error::add_error(
-                __(
-                    'Cannot get billing info for gateway %s on transaction because the primary registration has no attendee exists',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return null;
-        }
-        return $attendee->billing_info_for_payment_method($payment_method);
-    }
-
-
-    /**
-     * Gets PMD_ID
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function payment_method_ID()
-    {
-        return $this->get('PMD_ID');
-    }
-
-
-    /**
-     * Sets PMD_ID
-     *
-     * @param int $PMD_ID
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_payment_method_ID($PMD_ID)
-    {
-        $this->set('PMD_ID', $PMD_ID);
-    }
-
-
-    /**
-     * Gets the last-used payment method on this transaction
-     * (we COULD just use the last-made payment, but some payment methods, namely
-     * offline ones, dont' create payments)
-     *
-     * @return EE_Payment_Method
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function payment_method()
-    {
-        $pm = $this->get_first_related('Payment_Method');
-        if ($pm instanceof EE_Payment_Method) {
-            return $pm;
-        }
-        $last_payment = $this->last_payment();
-        if ($last_payment instanceof EE_Payment && $last_payment->payment_method()) {
-            return $last_payment->payment_method();
-        }
-        return null;
-    }
-
-
-    /**
-     * Gets the last payment made
-     *
-     * @return EE_Base_Class|EE_Payment
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function last_payment()
-    {
-        return $this->get_first_related('Payment', array('order_by' => array('PAY_ID' => 'desc')));
-    }
-
-
-    /**
-     * Gets all the line items which are unrelated to tickets on this transaction
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function non_ticket_line_items()
-    {
-        return EEM_Line_Item::instance()->get_all_non_ticket_line_items_for_transaction($this->ID());
-    }
-
-
-    /**
-     * possibly toggles TXN status
-     *
-     * @param  boolean $update whether to save the TXN
-     * @return bool whether the TXN was saved
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    public function update_status_based_on_total_paid($update = true)
-    {
-        // set transaction status based on comparison of TXN_paid vs TXN_total
-        if (EEH_Money::compare_floats($this->paid(), $this->total(), '>')) {
-            $new_txn_status = EEM_Transaction::overpaid_status_code;
-        } elseif (EEH_Money::compare_floats($this->paid(), $this->total())) {
-            $new_txn_status = EEM_Transaction::complete_status_code;
-        } elseif (EEH_Money::compare_floats($this->paid(), $this->total(), '<')) {
-            $new_txn_status = EEM_Transaction::incomplete_status_code;
-        } else {
-            throw new RuntimeException(
-                __('The total paid calculation for this transaction is inaccurate.', 'event_espresso')
-            );
-        }
-        if ($new_txn_status !== $this->status_ID()) {
-            $this->set_status($new_txn_status);
-            if ($update) {
-                return $this->save() ? true : false;
-            }
-        }
-        return false;
-    }
-
-
-    /**
-     * Updates the transaction's status and total_paid based on all the payments
-     * that apply to it
-     *
-     * @deprecated
-     * @return array|bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function update_based_on_payments()
-    {
-        EE_Error::doing_it_wrong(
-            __CLASS__ . '::' . __FUNCTION__,
-            sprintf(
-                __('This method is deprecated. Please use "%s" instead', 'event_espresso'),
-                'EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()'
-            ),
-            '4.6.0'
-        );
-        /** @type EE_Transaction_Processor $transaction_processor */
-        $transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
-        return $transaction_processor->update_transaction_and_registrations_after_checkout_or_payment($this);
-    }
-
-
-    /**
-     * @return string
-     */
-    public function old_txn_status()
-    {
-        return $this->_old_txn_status;
-    }
-
-
-    /**
-     * @param string $old_txn_status
-     */
-    public function set_old_txn_status($old_txn_status)
-    {
-        // only set the first time
-        if ($this->_old_txn_status === null) {
-            $this->_old_txn_status = $old_txn_status;
-        }
-    }
-
-
-    /**
-     * reg_status_updated
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function txn_status_updated()
-    {
-        return $this->status_ID() !== $this->_old_txn_status && $this->_old_txn_status !== null;
-    }
-
-
-    /**
-     * _reg_steps_completed
-     * if $check_all is TRUE, then returns TRUE if ALL reg steps have been marked as completed,
-     * if a $reg_step_slug is provided, then this step will be skipped when testing for completion
-     * if $check_all is FALSE and a $reg_step_slug is provided, then ONLY that reg step will be tested for completion
-     *
-     * @param string $reg_step_slug
-     * @param bool   $check_all
-     * @return bool|int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    private function _reg_steps_completed($reg_step_slug = '', $check_all = true)
-    {
-        $reg_steps = $this->reg_steps();
-        if (! is_array($reg_steps) || empty($reg_steps)) {
-            return false;
-        }
-        // loop thru reg steps array)
-        foreach ($reg_steps as $slug => $reg_step_completed) {
-            // if NOT checking ALL steps (only checking one step)
-            if (! $check_all) {
-                // and this is the one
-                if ($slug === $reg_step_slug) {
-                    return $reg_step_completed;
-                }
-                // skip to next reg step in loop
-                continue;
-            }
-            // $check_all must be true, else we would never have gotten to this point
-            if ($slug === $reg_step_slug) {
-                // if we reach this point, then we are testing either:
-                // all_reg_steps_completed_except() or
-                // all_reg_steps_completed_except_final_step(),
-                // and since this is the reg step EXCEPTION being tested
-                // we want to return true (yes true) if this reg step is NOT completed
-                // ie: "is everything completed except the final step?"
-                // "that is correct... the final step is not completed, but all others are."
-                return $reg_step_completed !== true;
-            }
-            if ($reg_step_completed !== true) {
-                // if any reg step is NOT completed, then ALL steps are not completed
-                return false;
-            }
-        }
-        return true;
-    }
-
-
-    /**
-     * all_reg_steps_completed
-     * returns:
-     *    true if ALL reg steps have been marked as completed
-     *        or false if any step is not completed
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function all_reg_steps_completed()
-    {
-        return $this->_reg_steps_completed();
-    }
-
-
-    /**
-     * all_reg_steps_completed_except
-     * returns:
-     *        true if ALL reg steps, except a particular step that you wish to skip over, have been marked as completed
-     *        or false if any other step is not completed
-     *        or false if ALL steps are completed including the exception you are testing !!!
-     *
-     * @param string $exception
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function all_reg_steps_completed_except($exception = '')
-    {
-        return $this->_reg_steps_completed($exception);
-    }
-
-
-    /**
-     * all_reg_steps_completed_except
-     * returns:
-     *        true if ALL reg steps, except the final step, have been marked as completed
-     *        or false if any step is not completed
-     *    or false if ALL steps are completed including the final step !!!
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function all_reg_steps_completed_except_final_step()
-    {
-        return $this->_reg_steps_completed('finalize_registration');
-    }
-
-
-    /**
-     * reg_step_completed
-     * returns:
-     *    true if a specific reg step has been marked as completed
-     *    a Unix timestamp if it has been initialized but not yet completed,
-     *    or false if it has not yet been initialized
-     *
-     * @param string $reg_step_slug
-     * @return bool|int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function reg_step_completed($reg_step_slug)
-    {
-        return $this->_reg_steps_completed($reg_step_slug, false);
-    }
-
-
-    /**
-     * completed_final_reg_step
-     * returns:
-     *    true if the finalize_registration reg step has been marked as completed
-     *    a Unix timestamp if it has been initialized but not yet completed,
-     *    or false if it has not yet been initialized
-     *
-     * @return bool|int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function final_reg_step_completed()
-    {
-        return $this->_reg_steps_completed('finalize_registration', false);
-    }
-
-
-    /**
-     * set_reg_step_initiated
-     * given a valid TXN_reg_step, this sets it's value to a unix timestamp
-     *
-     * @param string $reg_step_slug
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_reg_step_initiated($reg_step_slug)
-    {
-        return $this->_set_reg_step_completed_status($reg_step_slug, time());
-    }
-
-
-    /**
-     * set_reg_step_completed
-     * given a valid TXN_reg_step, this sets the step as completed
-     *
-     * @param string $reg_step_slug
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_reg_step_completed($reg_step_slug)
-    {
-        return $this->_set_reg_step_completed_status($reg_step_slug, true);
-    }
-
-
-    /**
-     * set_reg_step_completed
-     * given a valid TXN_reg_step slug, this sets the step as NOT completed
-     *
-     * @param string $reg_step_slug
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_reg_step_not_completed($reg_step_slug)
-    {
-        return $this->_set_reg_step_completed_status($reg_step_slug, false);
-    }
-
-
-    /**
-     * set_reg_step_completed
-     * given a valid reg step slug, this sets the TXN_reg_step completed status which is either:
-     *
-     * @param  string      $reg_step_slug
-     * @param  boolean|int $status
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    private function _set_reg_step_completed_status($reg_step_slug, $status)
-    {
-        // validate status
-        $status = is_bool($status) || is_int($status) ? $status : false;
-        // get reg steps array
-        $txn_reg_steps = $this->reg_steps();
-        // if reg step does NOT exist
-        if (! isset($txn_reg_steps[ $reg_step_slug ])) {
-            return false;
-        }
-        // if  we're trying to complete a step that is already completed
-        if ($txn_reg_steps[ $reg_step_slug ] === true) {
-            return true;
-        }
-        // if  we're trying to complete a step that hasn't even started
-        if ($status === true && $txn_reg_steps[ $reg_step_slug ] === false) {
-            return false;
-        }
-        // if current status value matches the incoming value (no change)
-        // type casting as int means values should collapse to either 0, 1, or a timestamp like 1234567890
-        if ((int) $txn_reg_steps[ $reg_step_slug ] === (int) $status) {
-            // this will happen in cases where multiple AJAX requests occur during the same step
-            return true;
-        }
-        // if we're trying to set a start time, but it has already been set...
-        if (is_numeric($status) && is_numeric($txn_reg_steps[ $reg_step_slug ])) {
-            // skip the update below, but don't return FALSE so that errors won't be displayed
-            return true;
-        }
-        // update completed status
-        $txn_reg_steps[ $reg_step_slug ] = $status;
-        $this->set_reg_steps($txn_reg_steps);
-        $this->save();
-        return true;
-    }
-
-
-    /**
-     * remove_reg_step
-     * given a valid TXN_reg_step slug, this will remove (unset)
-     * the reg step from the TXN reg step array
-     *
-     * @param string $reg_step_slug
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function remove_reg_step($reg_step_slug)
-    {
-        // get reg steps array
-        $txn_reg_steps = $this->reg_steps();
-        unset($txn_reg_steps[ $reg_step_slug ]);
-        $this->set_reg_steps($txn_reg_steps);
-    }
-
-
-    /**
-     * toggle_failed_transaction_status
-     * upgrades a TXNs status from failed to abandoned,
-     * meaning that contact information has been captured for at least one registrant
-     *
-     * @param bool $save
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function toggle_failed_transaction_status($save = true)
-    {
-        // if TXN status is still set as "failed"...
-        if ($this->status_ID() === EEM_Transaction::failed_status_code) {
-            $this->set_status(EEM_Transaction::abandoned_status_code);
-            if ($save) {
-                $this->save();
-            }
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * toggle_abandoned_transaction_status
-     * upgrades a TXNs status from failed or abandoned to incomplete
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function toggle_abandoned_transaction_status()
-    {
-        // if TXN status has not been updated already due to a payment, and is still set as "failed" or "abandoned"...
-        $txn_status = $this->status_ID();
-        if ($txn_status === EEM_Transaction::failed_status_code
-            || $txn_status === EEM_Transaction::abandoned_status_code
-        ) {
-            // if a contact record for the primary registrant has been created
-            if ($this->primary_registration() instanceof EE_Registration
-                && $this->primary_registration()->attendee() instanceof EE_Attendee
-            ) {
-                $this->set_status(EEM_Transaction::incomplete_status_code);
-            } else {
-                // no contact record? yer abandoned!
-                $this->set_status(EEM_Transaction::abandoned_status_code);
-            }
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * checks if an Abandoned TXN has any related payments, and if so,
-     * updates the TXN status based on the amount paid
-     *
-     * @throws EE_Error
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws InvalidArgumentException
-     * @throws RuntimeException
-     * @throws ReflectionException
-     */
-    public function verify_abandoned_transaction_status()
-    {
-        if ($this->status_ID() !== EEM_Transaction::abandoned_status_code) {
-            return;
-        }
-        $payments = $this->get_many_related('Payment');
-        if (! empty($payments)) {
-            foreach ($payments as $payment) {
-                if ($payment instanceof EE_Payment) {
-                    // kk this TXN should NOT be abandoned
-                    $this->update_status_based_on_total_paid();
-                    if (! (defined('DOING_AJAX') && DOING_AJAX) && is_admin()) {
-                        EE_Error::add_attention(
-                            sprintf(
-                                esc_html__(
-                                    'The status for Transaction #%1$d has been updated from "Abandoned" to "%2$s", because at least one payment has been made towards it. If the payment appears in the "Payment Details" table below, you may need to edit its status and/or other details as well.',
-                                    'event_espresso'
-                                ),
-                                $this->ID(),
-                                $this->pretty_status()
-                            )
-                        );
-                    }
-                    // get final reg step status
-                    $finalized = $this->final_reg_step_completed();
-                    // if the 'finalize_registration' step has been initiated (has a timestamp)
-                    // but has not yet been fully completed (TRUE)
-                    if (is_int($finalized) && $finalized !== false && $finalized !== true) {
-                        $this->set_reg_step_completed('finalize_registration');
-                        $this->save();
-                    }
-                }
-            }
-        }
-    }
+	/**
+	 * The length of time in seconds that a lock is applied before being considered expired.
+	 * It is not long because a transaction should only be locked for the duration of the request that locked it
+	 */
+	const LOCK_EXPIRATION = 2;
+
+	/**
+	 * txn status upon initial construction.
+	 *
+	 * @var string
+	 */
+	protected $_old_txn_status;
+
+
+	/**
+	 * @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  $date_formats            incoming date_formats in an array where the first value is the
+	 *                                        date_format and the second value is the time format
+	 * @return EE_Transaction
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function new_instance($props_n_values = array(), $timezone = null, $date_formats = array())
+	{
+		$has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
+		$txn = $has_object
+			? $has_object
+			: new self($props_n_values, false, $timezone, $date_formats);
+		if (! $has_object) {
+			$txn->set_old_txn_status($txn->status_ID());
+		}
+		return $txn;
+	}
+
+
+	/**
+	 * @param array  $props_n_values  incoming values from the database
+	 * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
+	 *                                the website will be used.
+	 * @return EE_Transaction
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function new_instance_from_db($props_n_values = array(), $timezone = null)
+	{
+		$txn = new self($props_n_values, true, $timezone);
+		$txn->set_old_txn_status($txn->status_ID());
+		return $txn;
+	}
+
+
+	/**
+	 * Sets a meta field indicating that this TXN is locked and should not be updated in the db.
+	 * If a lock has already been set, then we will attempt to remove it in case it has expired.
+	 * If that also fails, then an exception is thrown.
+	 *
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function lock()
+	{
+		// attempt to set lock, but if that fails...
+		if (! $this->add_extra_meta('lock', time(), true)) {
+			// then attempt to remove the lock in case it is expired
+			if ($this->_remove_expired_lock()) {
+				// if removal was successful, then try setting lock again
+				$this->lock();
+			} else {
+				// but if the lock can not be removed, then throw an exception
+				throw new EE_Error(
+					sprintf(
+						__(
+							'Could not lock Transaction %1$d because it is already locked, meaning another part of the system is currently editing it. It should already be unlocked by the time you read this, so please refresh the page and try again.',
+							'event_espresso'
+						),
+						$this->ID()
+					)
+				);
+			}
+		}
+	}
+
+
+	/**
+	 * removes transaction lock applied in EE_Transaction::lock()
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function unlock()
+	{
+		return $this->delete_extra_meta('lock');
+	}
+
+
+	/**
+	 * Decides whether or not now is the right time to update the transaction.
+	 * This is useful because we don't always know if it is safe to update the transaction
+	 * and its related data. why?
+	 * because it's possible that the transaction is being used in another
+	 * request and could overwrite anything we save.
+	 * So we want to only update the txn once we know that won't happen.
+	 * We also check that the lock isn't expired, and remove it if it is
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_locked()
+	{
+		// if TXN is not locked, then return false immediately
+		if (! $this->_get_lock()) {
+			return false;
+		}
+		// if not, then let's try and remove the lock in case it's expired...
+		// _remove_expired_lock() returns 0 when lock is valid (ie: removed = false)
+		// and a positive number if the lock was removed (ie: number of locks deleted),
+		// so we need to return the opposite
+		return ! $this->_remove_expired_lock() ? true : false;
+	}
+
+
+	/**
+	 * Gets the meta field indicating that this TXN is locked
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _get_lock()
+	{
+		return (int) $this->get_extra_meta('lock', true, 0);
+	}
+
+
+	/**
+	 * If the lock on this transaction is expired, then we want to remove it so that the transaction can be updated
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _remove_expired_lock()
+	{
+		$locked = $this->_get_lock();
+		if ($locked && time() - EE_Transaction::LOCK_EXPIRATION > $locked) {
+			return $this->unlock();
+		}
+		return 0;
+	}
+
+
+	/**
+	 * Set transaction total
+	 *
+	 * @param float $total total value of transaction
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_total($total = 0.00)
+	{
+		$this->set('TXN_total', (float) $total);
+	}
+
+
+	/**
+	 * Set Total Amount Paid to Date
+	 *
+	 * @param float $total_paid total amount paid to date (sum of all payments)
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_paid($total_paid = 0.00)
+	{
+		$this->set('TXN_paid', (float) $total_paid);
+	}
+
+
+	/**
+	 * Set transaction status
+	 *
+	 * @param string $status        whether the transaction is open, declined, accepted,
+	 *                              or any number of custom values that can be set
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_status($status = '')
+	{
+		$this->set('STS_ID', $status);
+	}
+
+
+	/**
+	 * Set hash salt
+	 *
+	 * @param string $hash_salt required for some payment gateways
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_hash_salt($hash_salt = '')
+	{
+		$this->set('TXN_hash_salt', $hash_salt);
+	}
+
+
+	/**
+	 * Sets TXN_reg_steps array
+	 *
+	 * @param array $txn_reg_steps
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_reg_steps(array $txn_reg_steps)
+	{
+		$this->set('TXN_reg_steps', $txn_reg_steps);
+	}
+
+
+	/**
+	 * Gets TXN_reg_steps
+	 *
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function reg_steps()
+	{
+		$TXN_reg_steps = $this->get('TXN_reg_steps');
+		return is_array($TXN_reg_steps) ? (array) $TXN_reg_steps : array();
+	}
+
+
+	/**
+	 * @return string of transaction's total cost, with currency symbol and decimal
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretty_total()
+	{
+		return $this->get_pretty('TXN_total');
+	}
+
+
+	/**
+	 * Gets the amount paid in a pretty string (formatted and with currency symbol)
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretty_paid()
+	{
+		return $this->get_pretty('TXN_paid');
+	}
+
+
+	/**
+	 * calculate the amount remaining for this transaction and return;
+	 *
+	 * @return float amount remaining
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function remaining()
+	{
+		return $this->total() - $this->paid();
+	}
+
+
+	/**
+	 * get Transaction Total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function total()
+	{
+		return (float) $this->get('TXN_total');
+	}
+
+
+	/**
+	 * get Total Amount Paid to Date
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function paid()
+	{
+		return (float) $this->get('TXN_paid');
+	}
+
+
+	/**
+	 * @return mixed|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_cart_session()
+	{
+		$session_data = (array) $this->get('TXN_session_data');
+		return isset($session_data['cart']) && $session_data['cart'] instanceof EE_Cart
+			? $session_data['cart']
+			: null;
+	}
+
+
+	/**
+	 * get Transaction session data
+	 *
+	 * @return array|mixed
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function session_data()
+	{
+		$session_data = $this->get('TXN_session_data');
+		if (empty($session_data)) {
+			$session_data = array(
+				'id'            => null,
+				'user_id'       => null,
+				'ip_address'    => null,
+				'user_agent'    => null,
+				'init_access'   => null,
+				'last_access'   => null,
+				'pages_visited' => array(),
+			);
+		}
+		return $session_data;
+	}
+
+
+	/**
+	 * Set session data within the TXN object
+	 *
+	 * @param EE_Session|array $session_data
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_txn_session_data($session_data)
+	{
+		if ($session_data instanceof EE_Session) {
+			$this->set('TXN_session_data', $session_data->get_session_data(null, true));
+		} else {
+			$this->set('TXN_session_data', $session_data);
+		}
+	}
+
+
+	/**
+	 * get Transaction hash salt
+	 *
+	 * @return mixed
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function hash_salt_()
+	{
+		return $this->get('TXN_hash_salt');
+	}
+
+
+	/**
+	 * Returns the transaction datetime as either:
+	 *            - unix timestamp format ($format = false, $gmt = true)
+	 *            - formatted date string including the UTC (timezone) offset ($format = true ($gmt
+	 *              has no affect with this option)), this also may include a timezone abbreviation if the
+	 *              set timezone in this class differs from what the timezone is on the blog.
+	 *            - formatted date string including the UTC (timezone) offset (default).
+	 *
+	 * @param boolean $format   - whether to return a unix timestamp (default) or formatted date string
+	 * @param boolean $gmt      - whether to return a unix timestamp with UTC offset applied (default)
+	 *                          or no UTC offset applied
+	 * @return string | int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function datetime($format = false, $gmt = false)
+	{
+		if ($format) {
+			return $this->get_pretty('TXN_timestamp');
+		}
+		if ($gmt) {
+			return $this->get_raw('TXN_timestamp');
+		}
+		return $this->get('TXN_timestamp');
+	}
+
+
+	/**
+	 * Gets registrations on this transaction
+	 *
+	 * @param array   $query_params array of query parameters
+	 * @param boolean $get_cached   TRUE to retrieve cached registrations or FALSE to pull from the db
+	 * @return EE_Base_Class[]|EE_Registration[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function registrations($query_params = array(), $get_cached = false)
+	{
+		$query_params = (empty($query_params) || ! is_array($query_params))
+			? array(
+				'order_by' => array(
+					'Event.EVT_name'     => 'ASC',
+					'Attendee.ATT_lname' => 'ASC',
+					'Attendee.ATT_fname' => 'ASC',
+				),
+			)
+			: $query_params;
+		$query_params = $get_cached ? array() : $query_params;
+		return $this->get_many_related('Registration', $query_params);
+	}
+
+
+	/**
+	 * Gets all the attendees for this transaction (handy for use with EE_Attendee's get_registrations_for_event
+	 * function for getting attendees and how many registrations they each have for an event)
+	 *
+	 * @return mixed EE_Attendee[] by default, int if $output is set to 'COUNT'
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function attendees()
+	{
+		return $this->get_many_related('Attendee', array(array('Registration.Transaction.TXN_ID' => $this->ID())));
+	}
+
+
+	/**
+	 * Gets payments for this transaction. Unlike other such functions, order by 'DESC' by default
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Base_Class[]|EE_Payment[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function payments($query_params = array())
+	{
+		return $this->get_many_related('Payment', $query_params);
+	}
+
+
+	/**
+	 * gets only approved payments for this transaction
+	 *
+	 * @return EE_Base_Class[]|EE_Payment[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function approved_payments()
+	{
+		EE_Registry::instance()->load_model('Payment');
+		return $this->get_many_related(
+			'Payment',
+			array(
+				array('STS_ID' => EEM_Payment::status_id_approved),
+				'order_by' => array('PAY_timestamp' => 'DESC'),
+			)
+		);
+	}
+
+
+	/**
+	 * Gets all payments which have not been approved
+	 *
+	 * @return EE_Base_Class[]|EEI_Payment[]
+	 * @throws EE_Error if a model is misconfigured somehow
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pending_payments()
+	{
+		return $this->get_many_related(
+			'Payment',
+			array(
+				array(
+					'STS_ID' => EEM_Payment::status_id_pending,
+				),
+				'order_by' => array(
+					'PAY_timestamp' => 'DESC',
+				),
+			)
+		);
+	}
+
+
+	/**
+	 * echoes $this->pretty_status()
+	 *
+	 * @param bool $show_icons
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function e_pretty_status($show_icons = false)
+	{
+		echo $this->pretty_status($show_icons);
+	}
+
+
+	/**
+	 * returns a pretty version of the status, good for displaying to users
+	 *
+	 * @param bool $show_icons
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretty_status($show_icons = false)
+	{
+		$status = EEM_Status::instance()->localized_status(
+			array($this->status_ID() => __('unknown', 'event_espresso')),
+			false,
+			'sentence'
+		);
+		$icon = '';
+		switch ($this->status_ID()) {
+			case EEM_Transaction::complete_status_code:
+				$icon = $show_icons ? '<span class="dashicons dashicons-yes ee-icon-size-24 green-text"></span>' : '';
+				break;
+			case EEM_Transaction::incomplete_status_code:
+				$icon = $show_icons ? '<span class="dashicons dashicons-marker ee-icon-size-16 lt-blue-text"></span>'
+					: '';
+				break;
+			case EEM_Transaction::abandoned_status_code:
+				$icon = $show_icons ? '<span class="dashicons dashicons-marker ee-icon-size-16 red-text"></span>' : '';
+				break;
+			case EEM_Transaction::failed_status_code:
+				$icon = $show_icons ? '<span class="dashicons dashicons-no ee-icon-size-16 red-text"></span>' : '';
+				break;
+			case EEM_Transaction::overpaid_status_code:
+				$icon = $show_icons ? '<span class="dashicons dashicons-plus ee-icon-size-16 orange-text"></span>' : '';
+				break;
+		}
+		return $icon . $status[ $this->status_ID() ];
+	}
+
+
+	/**
+	 * get Transaction Status
+	 *
+	 * @return mixed
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function status_ID()
+	{
+		return $this->get('STS_ID');
+	}
+
+
+	/**
+	 * Returns TRUE or FALSE for whether or not this transaction cost any money
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_free()
+	{
+		return EEH_Money::compare_floats($this->get('TXN_total'), 0, '==');
+	}
+
+
+	/**
+	 * Returns whether this transaction is complete
+	 * Useful in templates and other logic for deciding if we should ask for another payment...
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_completed()
+	{
+		return $this->status_ID() === EEM_Transaction::complete_status_code;
+	}
+
+
+	/**
+	 * Returns whether this transaction is incomplete
+	 * Useful in templates and other logic for deciding if we should ask for another payment...
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_incomplete()
+	{
+		return $this->status_ID() === EEM_Transaction::incomplete_status_code;
+	}
+
+
+	/**
+	 * Returns whether this transaction is overpaid
+	 * Useful in templates and other logic for deciding if monies need to be refunded
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_overpaid()
+	{
+		return $this->status_ID() === EEM_Transaction::overpaid_status_code;
+	}
+
+
+	/**
+	 * Returns whether this transaction was abandoned
+	 * meaning that the transaction/registration process was somehow interrupted and never completed
+	 * but that contact information exists for at least one registrant
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_abandoned()
+	{
+		return $this->status_ID() === EEM_Transaction::abandoned_status_code;
+	}
+
+
+	/**
+	 * Returns whether this transaction failed
+	 * meaning that the transaction/registration process was somehow interrupted and never completed
+	 * and that NO contact information exists for any registrants
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function failed()
+	{
+		return $this->status_ID() === EEM_Transaction::failed_status_code;
+	}
+
+
+	/**
+	 * This returns the url for the invoice of this transaction
+	 *
+	 * @param string $type 'html' or 'pdf' (default is pdf)
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function invoice_url($type = 'html')
+	{
+		$REG = $this->primary_registration();
+		if (! $REG instanceof EE_Registration) {
+			return '';
+		}
+		return $REG->invoice_url($type);
+	}
+
+
+	/**
+	 * Gets the primary registration only
+	 *
+	 * @return EE_Base_Class|EE_Registration
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function primary_registration()
+	{
+		$registrations = (array) $this->get_many_related(
+			'Registration',
+			array(array('REG_count' => EEM_Registration::PRIMARY_REGISTRANT_COUNT))
+		);
+		foreach ($registrations as $registration) {
+			// valid registration that is NOT cancelled or declined ?
+			if ($registration instanceof EE_Registration
+				&& ! in_array($registration->status_ID(), EEM_Registration::closed_reg_statuses(), true)
+			) {
+				return $registration;
+			}
+		}
+		// nothing valid found, so just return first thing from array of results
+		return reset($registrations);
+	}
+
+
+	/**
+	 * Gets the URL for viewing the receipt
+	 *
+	 * @param string $type 'pdf' or 'html' (default is 'html')
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function receipt_url($type = 'html')
+	{
+		$REG = $this->primary_registration();
+		if (! $REG instanceof EE_Registration) {
+			return '';
+		}
+		return $REG->receipt_url($type);
+	}
+
+
+	/**
+	 * Gets the URL of the thank you page with this registration REG_url_link added as
+	 * a query parameter
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function payment_overview_url()
+	{
+		$primary_registration = $this->primary_registration();
+		return $primary_registration instanceof EE_Registration ? $primary_registration->payment_overview_url() : false;
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function gateway_response_on_transaction()
+	{
+		$payment = $this->get_first_related('Payment');
+		return $payment instanceof EE_Payment ? $payment->gateway_response() : '';
+	}
+
+
+	/**
+	 * Get the status object of this object
+	 *
+	 * @return EE_Base_Class|EE_Status
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function status_obj()
+	{
+		return $this->get_first_related('Status');
+	}
+
+
+	/**
+	 * Gets all the extra meta info on this payment
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Base_Class[]|EE_Extra_Meta
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function extra_meta($query_params = array())
+	{
+		return $this->get_many_related('Extra_Meta', $query_params);
+	}
+
+
+	/**
+	 * Wrapper for _add_relation_to
+	 *
+	 * @param EE_Registration $registration
+	 * @return EE_Base_Class the relation was added to
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function add_registration(EE_Registration $registration)
+	{
+		return $this->_add_relation_to($registration, 'Registration');
+	}
+
+
+	/**
+	 * Removes the given registration from being related (even before saving this transaction).
+	 * If an ID/index is provided and this transaction isn't saved yet, removes it from list of cached relations
+	 *
+	 * @param int $registration_or_id
+	 * @return EE_Base_Class that was removed from being related
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function remove_registration_with_id($registration_or_id)
+	{
+		return $this->_remove_relation_to($registration_or_id, 'Registration');
+	}
+
+
+	/**
+	 * Gets all the line items which are for ACTUAL items
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function items_purchased()
+	{
+		return $this->line_items(array(array('LIN_type' => EEM_Line_Item::type_line_item)));
+	}
+
+
+	/**
+	 * Wrapper for _add_relation_to
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @return EE_Base_Class the relation was added to
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function add_line_item(EE_Line_Item $line_item)
+	{
+		return $this->_add_relation_to($line_item, 'Line_Item');
+	}
+
+
+	/**
+	 * Gets ALL the line items related to this transaction (unstructured)
+	 *
+	 * @param array $query_params
+	 * @return EE_Base_Class[]|EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function line_items($query_params = array())
+	{
+		return $this->get_many_related('Line_Item', $query_params);
+	}
+
+
+	/**
+	 * Gets all the line items which are taxes on the total
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function tax_items()
+	{
+		return $this->line_items(array(array('LIN_type' => EEM_Line_Item::type_tax)));
+	}
+
+
+	/**
+	 * Gets the total line item (which is a parent of all other related line items,
+	 * meaning it takes them all into account on its total)
+	 *
+	 * @param bool $create_if_not_found
+	 * @return \EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function total_line_item($create_if_not_found = true)
+	{
+		$item = $this->get_first_related('Line_Item', array(array('LIN_type' => EEM_Line_Item::type_total)));
+		if (! $item && $create_if_not_found) {
+			$item = EEH_Line_Item::create_total_line_item($this);
+		}
+		return $item;
+	}
+
+
+	/**
+	 * Returns the total amount of tax on this transaction
+	 * (assumes there's only one tax subtotal line item)
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function tax_total()
+	{
+		$tax_line_item = $this->tax_total_line_item();
+		if ($tax_line_item) {
+			return (float) $tax_line_item->total();
+		}
+		return (float) 0;
+	}
+
+
+	/**
+	 * Gets the tax subtotal line item (assumes there's only one)
+	 *
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function tax_total_line_item()
+	{
+		return EEH_Line_Item::get_taxes_subtotal($this->total_line_item());
+	}
+
+
+	/**
+	 * Gets the array of billing info for the gateway and for this transaction's primary registration's attendee.
+	 *
+	 * @return EE_Form_Section_Proper
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function billing_info()
+	{
+		$payment_method = $this->payment_method();
+		if (! $payment_method) {
+			EE_Error::add_error(
+				__(
+					'Could not find billing info for transaction because no gateway has been used for it yet',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return null;
+		}
+		$primary_reg = $this->primary_registration();
+		if (! $primary_reg) {
+			EE_Error::add_error(
+				__(
+					'Cannot get billing info for gateway %s on transaction because no primary registration exists',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return null;
+		}
+		$attendee = $primary_reg->attendee();
+		if (! $attendee) {
+			EE_Error::add_error(
+				__(
+					'Cannot get billing info for gateway %s on transaction because the primary registration has no attendee exists',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return null;
+		}
+		return $attendee->billing_info_for_payment_method($payment_method);
+	}
+
+
+	/**
+	 * Gets PMD_ID
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function payment_method_ID()
+	{
+		return $this->get('PMD_ID');
+	}
+
+
+	/**
+	 * Sets PMD_ID
+	 *
+	 * @param int $PMD_ID
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_payment_method_ID($PMD_ID)
+	{
+		$this->set('PMD_ID', $PMD_ID);
+	}
+
+
+	/**
+	 * Gets the last-used payment method on this transaction
+	 * (we COULD just use the last-made payment, but some payment methods, namely
+	 * offline ones, dont' create payments)
+	 *
+	 * @return EE_Payment_Method
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function payment_method()
+	{
+		$pm = $this->get_first_related('Payment_Method');
+		if ($pm instanceof EE_Payment_Method) {
+			return $pm;
+		}
+		$last_payment = $this->last_payment();
+		if ($last_payment instanceof EE_Payment && $last_payment->payment_method()) {
+			return $last_payment->payment_method();
+		}
+		return null;
+	}
+
+
+	/**
+	 * Gets the last payment made
+	 *
+	 * @return EE_Base_Class|EE_Payment
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function last_payment()
+	{
+		return $this->get_first_related('Payment', array('order_by' => array('PAY_ID' => 'desc')));
+	}
+
+
+	/**
+	 * Gets all the line items which are unrelated to tickets on this transaction
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function non_ticket_line_items()
+	{
+		return EEM_Line_Item::instance()->get_all_non_ticket_line_items_for_transaction($this->ID());
+	}
+
+
+	/**
+	 * possibly toggles TXN status
+	 *
+	 * @param  boolean $update whether to save the TXN
+	 * @return bool whether the TXN was saved
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	public function update_status_based_on_total_paid($update = true)
+	{
+		// set transaction status based on comparison of TXN_paid vs TXN_total
+		if (EEH_Money::compare_floats($this->paid(), $this->total(), '>')) {
+			$new_txn_status = EEM_Transaction::overpaid_status_code;
+		} elseif (EEH_Money::compare_floats($this->paid(), $this->total())) {
+			$new_txn_status = EEM_Transaction::complete_status_code;
+		} elseif (EEH_Money::compare_floats($this->paid(), $this->total(), '<')) {
+			$new_txn_status = EEM_Transaction::incomplete_status_code;
+		} else {
+			throw new RuntimeException(
+				__('The total paid calculation for this transaction is inaccurate.', 'event_espresso')
+			);
+		}
+		if ($new_txn_status !== $this->status_ID()) {
+			$this->set_status($new_txn_status);
+			if ($update) {
+				return $this->save() ? true : false;
+			}
+		}
+		return false;
+	}
+
+
+	/**
+	 * Updates the transaction's status and total_paid based on all the payments
+	 * that apply to it
+	 *
+	 * @deprecated
+	 * @return array|bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function update_based_on_payments()
+	{
+		EE_Error::doing_it_wrong(
+			__CLASS__ . '::' . __FUNCTION__,
+			sprintf(
+				__('This method is deprecated. Please use "%s" instead', 'event_espresso'),
+				'EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()'
+			),
+			'4.6.0'
+		);
+		/** @type EE_Transaction_Processor $transaction_processor */
+		$transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
+		return $transaction_processor->update_transaction_and_registrations_after_checkout_or_payment($this);
+	}
+
+
+	/**
+	 * @return string
+	 */
+	public function old_txn_status()
+	{
+		return $this->_old_txn_status;
+	}
+
+
+	/**
+	 * @param string $old_txn_status
+	 */
+	public function set_old_txn_status($old_txn_status)
+	{
+		// only set the first time
+		if ($this->_old_txn_status === null) {
+			$this->_old_txn_status = $old_txn_status;
+		}
+	}
+
+
+	/**
+	 * reg_status_updated
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function txn_status_updated()
+	{
+		return $this->status_ID() !== $this->_old_txn_status && $this->_old_txn_status !== null;
+	}
+
+
+	/**
+	 * _reg_steps_completed
+	 * if $check_all is TRUE, then returns TRUE if ALL reg steps have been marked as completed,
+	 * if a $reg_step_slug is provided, then this step will be skipped when testing for completion
+	 * if $check_all is FALSE and a $reg_step_slug is provided, then ONLY that reg step will be tested for completion
+	 *
+	 * @param string $reg_step_slug
+	 * @param bool   $check_all
+	 * @return bool|int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	private function _reg_steps_completed($reg_step_slug = '', $check_all = true)
+	{
+		$reg_steps = $this->reg_steps();
+		if (! is_array($reg_steps) || empty($reg_steps)) {
+			return false;
+		}
+		// loop thru reg steps array)
+		foreach ($reg_steps as $slug => $reg_step_completed) {
+			// if NOT checking ALL steps (only checking one step)
+			if (! $check_all) {
+				// and this is the one
+				if ($slug === $reg_step_slug) {
+					return $reg_step_completed;
+				}
+				// skip to next reg step in loop
+				continue;
+			}
+			// $check_all must be true, else we would never have gotten to this point
+			if ($slug === $reg_step_slug) {
+				// if we reach this point, then we are testing either:
+				// all_reg_steps_completed_except() or
+				// all_reg_steps_completed_except_final_step(),
+				// and since this is the reg step EXCEPTION being tested
+				// we want to return true (yes true) if this reg step is NOT completed
+				// ie: "is everything completed except the final step?"
+				// "that is correct... the final step is not completed, but all others are."
+				return $reg_step_completed !== true;
+			}
+			if ($reg_step_completed !== true) {
+				// if any reg step is NOT completed, then ALL steps are not completed
+				return false;
+			}
+		}
+		return true;
+	}
+
+
+	/**
+	 * all_reg_steps_completed
+	 * returns:
+	 *    true if ALL reg steps have been marked as completed
+	 *        or false if any step is not completed
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function all_reg_steps_completed()
+	{
+		return $this->_reg_steps_completed();
+	}
+
+
+	/**
+	 * all_reg_steps_completed_except
+	 * returns:
+	 *        true if ALL reg steps, except a particular step that you wish to skip over, have been marked as completed
+	 *        or false if any other step is not completed
+	 *        or false if ALL steps are completed including the exception you are testing !!!
+	 *
+	 * @param string $exception
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function all_reg_steps_completed_except($exception = '')
+	{
+		return $this->_reg_steps_completed($exception);
+	}
+
+
+	/**
+	 * all_reg_steps_completed_except
+	 * returns:
+	 *        true if ALL reg steps, except the final step, have been marked as completed
+	 *        or false if any step is not completed
+	 *    or false if ALL steps are completed including the final step !!!
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function all_reg_steps_completed_except_final_step()
+	{
+		return $this->_reg_steps_completed('finalize_registration');
+	}
+
+
+	/**
+	 * reg_step_completed
+	 * returns:
+	 *    true if a specific reg step has been marked as completed
+	 *    a Unix timestamp if it has been initialized but not yet completed,
+	 *    or false if it has not yet been initialized
+	 *
+	 * @param string $reg_step_slug
+	 * @return bool|int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function reg_step_completed($reg_step_slug)
+	{
+		return $this->_reg_steps_completed($reg_step_slug, false);
+	}
+
+
+	/**
+	 * completed_final_reg_step
+	 * returns:
+	 *    true if the finalize_registration reg step has been marked as completed
+	 *    a Unix timestamp if it has been initialized but not yet completed,
+	 *    or false if it has not yet been initialized
+	 *
+	 * @return bool|int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function final_reg_step_completed()
+	{
+		return $this->_reg_steps_completed('finalize_registration', false);
+	}
+
+
+	/**
+	 * set_reg_step_initiated
+	 * given a valid TXN_reg_step, this sets it's value to a unix timestamp
+	 *
+	 * @param string $reg_step_slug
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_reg_step_initiated($reg_step_slug)
+	{
+		return $this->_set_reg_step_completed_status($reg_step_slug, time());
+	}
+
+
+	/**
+	 * set_reg_step_completed
+	 * given a valid TXN_reg_step, this sets the step as completed
+	 *
+	 * @param string $reg_step_slug
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_reg_step_completed($reg_step_slug)
+	{
+		return $this->_set_reg_step_completed_status($reg_step_slug, true);
+	}
+
+
+	/**
+	 * set_reg_step_completed
+	 * given a valid TXN_reg_step slug, this sets the step as NOT completed
+	 *
+	 * @param string $reg_step_slug
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_reg_step_not_completed($reg_step_slug)
+	{
+		return $this->_set_reg_step_completed_status($reg_step_slug, false);
+	}
+
+
+	/**
+	 * set_reg_step_completed
+	 * given a valid reg step slug, this sets the TXN_reg_step completed status which is either:
+	 *
+	 * @param  string      $reg_step_slug
+	 * @param  boolean|int $status
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	private function _set_reg_step_completed_status($reg_step_slug, $status)
+	{
+		// validate status
+		$status = is_bool($status) || is_int($status) ? $status : false;
+		// get reg steps array
+		$txn_reg_steps = $this->reg_steps();
+		// if reg step does NOT exist
+		if (! isset($txn_reg_steps[ $reg_step_slug ])) {
+			return false;
+		}
+		// if  we're trying to complete a step that is already completed
+		if ($txn_reg_steps[ $reg_step_slug ] === true) {
+			return true;
+		}
+		// if  we're trying to complete a step that hasn't even started
+		if ($status === true && $txn_reg_steps[ $reg_step_slug ] === false) {
+			return false;
+		}
+		// if current status value matches the incoming value (no change)
+		// type casting as int means values should collapse to either 0, 1, or a timestamp like 1234567890
+		if ((int) $txn_reg_steps[ $reg_step_slug ] === (int) $status) {
+			// this will happen in cases where multiple AJAX requests occur during the same step
+			return true;
+		}
+		// if we're trying to set a start time, but it has already been set...
+		if (is_numeric($status) && is_numeric($txn_reg_steps[ $reg_step_slug ])) {
+			// skip the update below, but don't return FALSE so that errors won't be displayed
+			return true;
+		}
+		// update completed status
+		$txn_reg_steps[ $reg_step_slug ] = $status;
+		$this->set_reg_steps($txn_reg_steps);
+		$this->save();
+		return true;
+	}
+
+
+	/**
+	 * remove_reg_step
+	 * given a valid TXN_reg_step slug, this will remove (unset)
+	 * the reg step from the TXN reg step array
+	 *
+	 * @param string $reg_step_slug
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function remove_reg_step($reg_step_slug)
+	{
+		// get reg steps array
+		$txn_reg_steps = $this->reg_steps();
+		unset($txn_reg_steps[ $reg_step_slug ]);
+		$this->set_reg_steps($txn_reg_steps);
+	}
+
+
+	/**
+	 * toggle_failed_transaction_status
+	 * upgrades a TXNs status from failed to abandoned,
+	 * meaning that contact information has been captured for at least one registrant
+	 *
+	 * @param bool $save
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function toggle_failed_transaction_status($save = true)
+	{
+		// if TXN status is still set as "failed"...
+		if ($this->status_ID() === EEM_Transaction::failed_status_code) {
+			$this->set_status(EEM_Transaction::abandoned_status_code);
+			if ($save) {
+				$this->save();
+			}
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * toggle_abandoned_transaction_status
+	 * upgrades a TXNs status from failed or abandoned to incomplete
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function toggle_abandoned_transaction_status()
+	{
+		// if TXN status has not been updated already due to a payment, and is still set as "failed" or "abandoned"...
+		$txn_status = $this->status_ID();
+		if ($txn_status === EEM_Transaction::failed_status_code
+			|| $txn_status === EEM_Transaction::abandoned_status_code
+		) {
+			// if a contact record for the primary registrant has been created
+			if ($this->primary_registration() instanceof EE_Registration
+				&& $this->primary_registration()->attendee() instanceof EE_Attendee
+			) {
+				$this->set_status(EEM_Transaction::incomplete_status_code);
+			} else {
+				// no contact record? yer abandoned!
+				$this->set_status(EEM_Transaction::abandoned_status_code);
+			}
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * checks if an Abandoned TXN has any related payments, and if so,
+	 * updates the TXN status based on the amount paid
+	 *
+	 * @throws EE_Error
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidArgumentException
+	 * @throws RuntimeException
+	 * @throws ReflectionException
+	 */
+	public function verify_abandoned_transaction_status()
+	{
+		if ($this->status_ID() !== EEM_Transaction::abandoned_status_code) {
+			return;
+		}
+		$payments = $this->get_many_related('Payment');
+		if (! empty($payments)) {
+			foreach ($payments as $payment) {
+				if ($payment instanceof EE_Payment) {
+					// kk this TXN should NOT be abandoned
+					$this->update_status_based_on_total_paid();
+					if (! (defined('DOING_AJAX') && DOING_AJAX) && is_admin()) {
+						EE_Error::add_attention(
+							sprintf(
+								esc_html__(
+									'The status for Transaction #%1$d has been updated from "Abandoned" to "%2$s", because at least one payment has been made towards it. If the payment appears in the "Payment Details" table below, you may need to edit its status and/or other details as well.',
+									'event_espresso'
+								),
+								$this->ID(),
+								$this->pretty_status()
+							)
+						);
+					}
+					// get final reg step status
+					$finalized = $this->final_reg_step_completed();
+					// if the 'finalize_registration' step has been initiated (has a timestamp)
+					// but has not yet been fully completed (TRUE)
+					if (is_int($finalized) && $finalized !== false && $finalized !== true) {
+						$this->set_reg_step_completed('finalize_registration');
+						$this->save();
+					}
+				}
+			}
+		}
+	}
 }