eventespresso / event-espresso-core

core/db_classes/EE_Datetime.class.php

Spacing +9 added lines, -9 removed lines

@@ -495,7 +495,7 @@ 
             $date_or_time,
             $echo
         );
-        if (! $echo) {
+        if ( ! $echo) {
             return $dtt;
         }
         return '';
@@ -597,7 +597,7 @@ 
             ' ',
             $this->get_i18n_datetime('DTT_EVT_end', $dt_frmt)
         );
-        return $start !== $end ? $start . $conjunction . $end : $start;
+        return $start !== $end ? $start.$conjunction.$end : $start;
     }
 
 
@@ -705,7 +705,7 @@ 
             ' ',
             $this->get_i18n_datetime('DTT_EVT_end', $tm_format)
         );
-        return $start !== $end ? $start . $conjunction . $end : $start;
+        return $start !== $end ? $start.$conjunction.$end : $start;
     }
 
 
@@ -750,7 +750,7 @@ 
     ) {
         $dt_format = ! empty($dt_format) ? $dt_format : $this->_dt_frmt;
         $tm_format = ! empty($tm_format) ? $tm_format : $this->_tm_frmt;
-        $full_format = $dt_format . $separator . $tm_format;
+        $full_format = $dt_format.$separator.$tm_format;
         // the range output depends on various conditions
         switch (true) {
             // start date timestamp and end date timestamp are the same.
@@ -991,7 +991,7 @@ 
         // tickets remaining available for purchase
         // no need for special checks for infinite, because if DTT_reg_limit == EE_INF, then EE_INF - x = EE_INF
         $dtt_remaining = $this->reg_limit() - $this->sold_and_reserved();
-        if (! $consider_tickets) {
+        if ( ! $consider_tickets) {
             return $dtt_remaining;
         }
         $tickets_remaining = $this->tickets_remaining();
@@ -1015,7 +1015,7 @@ 
     {
         $sum = 0;
         $tickets = $this->tickets($query_params);
-        if (! empty($tickets)) {
+        if ( ! empty($tickets)) {
             foreach ($tickets as $ticket) {
                 if ($ticket instanceof EE_Ticket) {
                     // get the actual amount of tickets that can be sold
@@ -1166,20 +1166,20 @@ 
     {
         if ($use_dtt_name) {
             $dtt_name = $this->name();
-            if (! empty($dtt_name)) {
+            if ( ! empty($dtt_name)) {
                 return $dtt_name;
             }
         }
         // first condition is to see if the months are different
         if (date('m', $this->get_raw('DTT_EVT_start')) !== date('m', $this->get_raw('DTT_EVT_end'))
         ) {
-            $display_date = $this->start_date('M j\, Y g:i a') . ' - ' . $this->end_date('M j\, Y g:i a');
+            $display_date = $this->start_date('M j\, Y g:i a').' - '.$this->end_date('M j\, Y g:i a');
             // next condition is if its the same month but different day
         } else {
             if (date('m', $this->get_raw('DTT_EVT_start')) === date('m', $this->get_raw('DTT_EVT_end'))
                 && date('d', $this->get_raw('DTT_EVT_start')) !== date('d', $this->get_raw('DTT_EVT_end'))
             ) {
-                $display_date = $this->start_date('M j\, g:i a') . ' - ' . $this->end_date('M j\, g:i a Y');
+                $display_date = $this->start_date('M j\, g:i a').' - '.$this->end_date('M j\, g:i a Y');
             } else {
                 $display_date = $this->start_date('F j\, Y')
                                 . ' @ '

Indentation +1402 added lines, -1402 removed lines

@@ -13,1410 +13,1410 @@
 class EE_Datetime extends EE_Soft_Delete_Base_Class
 {
 
-    /**
-     * constant used by get_active_status, indicates datetime has no more available spaces
-     */
-    const sold_out = 'DTS';
-
-    /**
-     * constant used by get_active_status, indicating datetime is still active (even is not over, can be registered-for)
-     */
-    const active = 'DTA';
-
-    /**
-     * constant used by get_active_status, indicating the datetime cannot be used for registrations yet, but has not
-     * expired
-     */
-    const upcoming = 'DTU';
-
-    /**
-     * Datetime is postponed
-     */
-    const postponed = 'DTP';
-
-    /**
-     * Datetime is cancelled
-     */
-    const cancelled = 'DTC';
-
-    /**
-     * constant used by get_active_status, indicates datetime has expired (event is over)
-     */
-    const expired = 'DTE';
-
-    /**
-     * constant used in various places indicating that an event is INACTIVE (not yet ready to be published)
-     */
-    const inactive = 'DTI';
-
-
-    /**
-     * @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  $date_formats      incoming date_formats in an array where the first value is the date_format
-     *                                  and the second value is the time format
-     * @return EE_Datetime
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public static function new_instance($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, $date_formats);
-    }
-
-
-    /**
-     * @param array  $props_n_values  incoming values from the database
-     * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
-     *                                the website will be used.
-     * @return EE_Datetime
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public static function new_instance_from_db($props_n_values = array(), $timezone = null)
-    {
-        return new self($props_n_values, true, $timezone);
-    }
-
-
-    /**
-     * @param $name
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_name($name)
-    {
-        $this->set('DTT_name', $name);
-    }
-
-
-    /**
-     * @param $description
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_description($description)
-    {
-        $this->set('DTT_description', $description);
-    }
-
-
-    /**
-     * Set event start date
-     * set the start date for an event
-     *
-     * @param string $date a string representation of the event's date ex:  Dec. 25, 2025 or 12-25-2025
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_start_date($date)
-    {
-        $this->_set_date_for($date, 'DTT_EVT_start');
-    }
-
-
-    /**
-     * Set event start time
-     * set the start time for an event
-     *
-     * @param string $time a string representation of the event time ex:  9am  or  7:30 PM
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_start_time($time)
-    {
-        $this->_set_time_for($time, 'DTT_EVT_start');
-    }
-
-
-    /**
-     * Set event end date
-     * set the end date for an event
-     *
-     * @param string $date a string representation of the event's date ex:  Dec. 25, 2025 or 12-25-2025
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_end_date($date)
-    {
-        $this->_set_date_for($date, 'DTT_EVT_end');
-    }
-
-
-    /**
-     * Set event end time
-     * set the end time for an event
-     *
-     * @param string $time a string representation of the event time ex:  9am  or  7:30 PM
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_end_time($time)
-    {
-        $this->_set_time_for($time, 'DTT_EVT_end');
-    }
-
-
-    /**
-     * Set registration limit
-     * set the maximum number of attendees that can be registered for this datetime slot
-     *
-     * @param int $reg_limit
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_reg_limit($reg_limit)
-    {
-        $this->set('DTT_reg_limit', $reg_limit);
-    }
-
-
-    /**
-     * get the number of tickets sold for this datetime slot
-     *
-     * @return mixed int on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function sold()
-    {
-        return $this->get_raw('DTT_sold');
-    }
-
-
-    /**
-     * @param int $sold
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_sold($sold)
-    {
-        // sold can not go below zero
-        $sold = max(0, $sold);
-        $this->set('DTT_sold', $sold);
-    }
-
-
-    /**
-     * Increments sold by amount passed by $qty, and persists it immediately to the database.
-     * Simultaneously decreases the reserved count, unless $also_decrease_reserved is false.
-     *
-     * @param int $qty
-     * @param boolean $also_decrease_reserved
-     * @return boolean indicating success
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function increaseSold($qty = 1, $also_decrease_reserved = true)
-    {
-        $qty = absint($qty);
-        if ($also_decrease_reserved) {
-            $success = $this->adjustNumericFieldsInDb(
-                [
-                    'DTT_reserved' => $qty * -1,
-                    'DTT_sold' => $qty
-                ]
-            );
-        } else {
-            $success = $this->adjustNumericFieldsInDb(
-                [
-                    'DTT_sold' => $qty
-                ]
-            );
-        }
-
-        do_action(
-            'AHEE__EE_Datetime__increase_sold',
-            $this,
-            $qty,
-            $this->sold(),
-            $success
-        );
-        return $success;
-    }
-
-
-    /**
-     * Decrements (subtracts) sold amount passed by $qty directly in the DB and on the model object. (Ie, no need
-     * to save afterwards.)
-     *
-     * @param int $qty
-     * @return boolean indicating success
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function decreaseSold($qty = 1)
-    {
-        $qty = absint($qty);
-        $success = $this->adjustNumericFieldsInDb(
-            [
-                'DTT_sold' => $qty * -1
-            ]
-        );
-        do_action(
-            'AHEE__EE_Datetime__decrease_sold',
-            $this,
-            $qty,
-            $this->sold(),
-            $success
-        );
-        return $success;
-    }
-
-
-    /**
-     * Gets qty of reserved tickets for this datetime
-     *
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function reserved()
-    {
-        return $this->get_raw('DTT_reserved');
-    }
-
-
-    /**
-     * Sets qty of reserved tickets for this datetime
-     *
-     * @param int $reserved
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_reserved($reserved)
-    {
-        // reserved can not go below zero
-        $reserved = max(0, (int) $reserved);
-        $this->set('DTT_reserved', $reserved);
-    }
-
-
-    /**
-     * Increments reserved by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @param int $qty
-     * @return boolean indicating success
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function increaseReserved($qty = 1)
-    {
-        $qty = absint($qty);
-        $success = $this->incrementFieldConditionallyInDb(
-            'DTT_reserved',
-            'DTT_sold',
-            'DTT_reg_limit',
-            $qty
-        );
-        do_action(
-            'AHEE__EE_Datetime__increase_reserved',
-            $this,
-            $qty,
-            $this->reserved(),
-            $success
-        );
-        return $success;
-    }
-
-
-    /**
-     * Decrements (subtracts) reserved by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @param int $qty
-     * @return boolean indicating success
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function decreaseReserved($qty = 1)
-    {
-        $qty = absint($qty);
-        $success = $this->adjustNumericFieldsInDb(
-            [
-                'DTT_reserved' => $qty * -1
-            ]
-        );
-        do_action(
-            'AHEE__EE_Datetime__decrease_reserved',
-            $this,
-            $qty,
-            $this->reserved(),
-            $success
-        );
-        return $success;
-    }
-
-
-    /**
-     * total sold and reserved tickets
-     *
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function sold_and_reserved()
-    {
-        return $this->sold() + $this->reserved();
-    }
-
-
-    /**
-     * returns the datetime name
-     *
-     * @return string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function name()
-    {
-        return $this->get('DTT_name');
-    }
-
-
-    /**
-     * returns the datetime description
-     *
-     * @return string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function description()
-    {
-        return $this->get('DTT_description');
-    }
-
-
-    /**
-     * This helper simply returns whether the event_datetime for the current datetime is a primary datetime
-     *
-     * @return boolean  TRUE if is primary, FALSE if not.
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function is_primary()
-    {
-        return $this->get('DTT_is_primary');
-    }
-
-
-    /**
-     * This helper simply returns the order for the datetime
-     *
-     * @return int  The order of the datetime for this event.
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function order()
-    {
-        return $this->get('DTT_order');
-    }
-
-
-    /**
-     * This helper simply returns the parent id for the datetime
-     *
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function parent()
-    {
-        return $this->get('DTT_parent');
-    }
-
-
-    /**
-     * show date and/or time
-     *
-     * @param string $date_or_time    whether to display a date or time or both
-     * @param string $start_or_end    whether to display start or end datetimes
-     * @param string $dt_frmt
-     * @param string $tm_frmt
-     * @param bool   $echo            whether we echo or return (note echoing uses "pretty" formats,
-     *                                otherwise we use the standard formats)
-     * @return string|bool  string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    private function _show_datetime(
-        $date_or_time = null,
-        $start_or_end = 'start',
-        $dt_frmt = '',
-        $tm_frmt = '',
-        $echo = false
-    ) {
-        $field_name = "DTT_EVT_{$start_or_end}";
-        $dtt = $this->_get_datetime(
-            $field_name,
-            $dt_frmt,
-            $tm_frmt,
-            $date_or_time,
-            $echo
-        );
-        if (! $echo) {
-            return $dtt;
-        }
-        return '';
-    }
-
-
-    /**
-     * get event start date.  Provide either the date format, or NULL to re-use the
-     * last-used format, or '' to use the default date format
-     *
-     * @param string $dt_frmt string representation of date format defaults to 'F j, Y'
-     * @return mixed            string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function start_date($dt_frmt = '')
-    {
-        return $this->_show_datetime('D', 'start', $dt_frmt);
-    }
-
-
-    /**
-     * Echoes start_date()
-     *
-     * @param string $dt_frmt
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_start_date($dt_frmt = '')
-    {
-        $this->_show_datetime('D', 'start', $dt_frmt, null, true);
-    }
-
-
-    /**
-     * get end date. Provide either the date format, or NULL to re-use the
-     * last-used format, or '' to use the default date format
-     *
-     * @param string $dt_frmt string representation of date format defaults to 'F j, Y'
-     * @return mixed            string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function end_date($dt_frmt = '')
-    {
-        return $this->_show_datetime('D', 'end', $dt_frmt);
-    }
-
-
-    /**
-     * Echoes the end date. See end_date()
-     *
-     * @param string $dt_frmt
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_end_date($dt_frmt = '')
-    {
-        $this->_show_datetime('D', 'end', $dt_frmt, null, true);
-    }
-
-
-    /**
-     * get date_range - meaning the start AND end date
-     *
-     * @access public
-     * @param string $dt_frmt     string representation of date format defaults to WP settings
-     * @param string $conjunction conjunction junction what's your function ?
-     *                            this string joins the start date with the end date ie: Jan 01 "to" Dec 31
-     * @return mixed              string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function date_range($dt_frmt = '', $conjunction = ' - ')
-    {
-        $dt_frmt = ! empty($dt_frmt) ? $dt_frmt : $this->_dt_frmt;
-        $start = str_replace(
-            ' ',
-            ' ',
-            $this->get_i18n_datetime('DTT_EVT_start', $dt_frmt)
-        );
-        $end = str_replace(
-            ' ',
-            ' ',
-            $this->get_i18n_datetime('DTT_EVT_end', $dt_frmt)
-        );
-        return $start !== $end ? $start . $conjunction . $end : $start;
-    }
-
-
-    /**
-     * @param string $dt_frmt
-     * @param string $conjunction
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_date_range($dt_frmt = '', $conjunction = ' - ')
-    {
-        echo $this->date_range($dt_frmt, $conjunction);
-    }
-
-
-    /**
-     * get start time
-     *
-     * @param string $tm_format - string representation of time format defaults to 'g:i a'
-     * @return mixed        string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function start_time($tm_format = '')
-    {
-        return $this->_show_datetime('T', 'start', null, $tm_format);
-    }
-
-
-    /**
-     * @param string $tm_format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_start_time($tm_format = '')
-    {
-        $this->_show_datetime('T', 'start', null, $tm_format, true);
-    }
-
-
-    /**
-     * get end time
-     *
-     * @param string $tm_format string representation of time format defaults to 'g:i a'
-     * @return mixed                string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function end_time($tm_format = '')
-    {
-        return $this->_show_datetime('T', 'end', null, $tm_format);
-    }
-
-
-    /**
-     * @param string $tm_format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_end_time($tm_format = '')
-    {
-        $this->_show_datetime('T', 'end', null, $tm_format, true);
-    }
-
-
-    /**
-     * get time_range
-     *
-     * @access public
-     * @param string $tm_format   string representation of time format defaults to 'g:i a'
-     * @param string $conjunction conjunction junction what's your function ?
-     *                            this string joins the start date with the end date ie: Jan 01 "to" Dec 31
-     * @return mixed              string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function time_range($tm_format = '', $conjunction = ' - ')
-    {
-        $tm_format = ! empty($tm_format) ? $tm_format : $this->_tm_frmt;
-        $start = str_replace(
-            ' ',
-            ' ',
-            $this->get_i18n_datetime('DTT_EVT_start', $tm_format)
-        );
-        $end = str_replace(
-            ' ',
-            ' ',
-            $this->get_i18n_datetime('DTT_EVT_end', $tm_format)
-        );
-        return $start !== $end ? $start . $conjunction . $end : $start;
-    }
-
-
-    /**
-     * @param string $tm_format
-     * @param string $conjunction
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_time_range($tm_format = '', $conjunction = ' - ')
-    {
-        echo $this->time_range($tm_format, $conjunction);
-    }
-
-
-    /**
-     * This returns a range representation of the date and times.
-     * Output is dependent on the difference (or similarity) between DTT_EVT_start and DTT_EVT_end.
-     * Also, the return value is localized.
-     *
-     * @param string $dt_format
-     * @param string $tm_format
-     * @param string $conjunction used between two different dates or times.
-     *                            ex: Dec 1{$conjunction}}Dec 6, or 2pm{$conjunction}3pm
-     * @param string $separator   used between the date and time formats.
-     *                            ex: Dec 1, 2016{$separator}2pm
-     * @return string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function date_and_time_range(
-        $dt_format = '',
-        $tm_format = '',
-        $conjunction = ' - ',
-        $separator = ' '
-    ) {
-        $dt_format = ! empty($dt_format) ? $dt_format : $this->_dt_frmt;
-        $tm_format = ! empty($tm_format) ? $tm_format : $this->_tm_frmt;
-        $full_format = $dt_format . $separator . $tm_format;
-        // the range output depends on various conditions
-        switch (true) {
-            // start date timestamp and end date timestamp are the same.
-            case ($this->get_raw('DTT_EVT_start') === $this->get_raw('DTT_EVT_end')):
-                $output = $this->get_i18n_datetime('DTT_EVT_start', $full_format);
-                break;
-            // start and end date are the same but times are different
-            case ($this->start_date() === $this->end_date()):
-                $output = $this->get_i18n_datetime('DTT_EVT_start', $full_format)
-                          . $conjunction
-                          . $this->get_i18n_datetime('DTT_EVT_end', $tm_format);
-                break;
-            // all other conditions
-            default:
-                $output = $this->get_i18n_datetime('DTT_EVT_start', $full_format)
-                          . $conjunction
-                          . $this->get_i18n_datetime('DTT_EVT_end', $full_format);
-                break;
-        }
-        return $output;
-    }
-
-
-    /**
-     * This echos the results of date and time range.
-     *
-     * @see date_and_time_range() for more details on purpose.
-     * @param string $dt_format
-     * @param string $tm_format
-     * @param string $conjunction
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_date_and_time_range($dt_format = '', $tm_format = '', $conjunction = ' - ')
-    {
-        echo $this->date_and_time_range($dt_format, $tm_format, $conjunction);
-    }
-
-
-    /**
-     * get start date and start time
-     *
-     * @param    string $dt_format - string representation of date format defaults to 'F j, Y'
-     * @param    string $tm_format - string representation of time format defaults to 'g:i a'
-     * @return    mixed    string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function start_date_and_time($dt_format = '', $tm_format = '')
-    {
-        return $this->_show_datetime('', 'start', $dt_format, $tm_format);
-    }
-
-
-    /**
-     * @param string $dt_frmt
-     * @param string $tm_format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_start_date_and_time($dt_frmt = '', $tm_format = '')
-    {
-        $this->_show_datetime('', 'start', $dt_frmt, $tm_format, true);
-    }
-
-
-    /**
-     * Shows the length of the event (start to end time).
-     * Can be shown in 'seconds','minutes','hours', or 'days'.
-     * By default, rounds up. (So if you use 'days', and then event
-     * only occurs for 1 hour, it will return 1 day).
-     *
-     * @param string $units 'seconds','minutes','hours','days'
-     * @param bool   $round_up
-     * @return float|int|mixed
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function length($units = 'seconds', $round_up = false)
-    {
-        $start = $this->get_raw('DTT_EVT_start');
-        $end = $this->get_raw('DTT_EVT_end');
-        $length_in_units = $end - $start;
-        switch ($units) {
-            // NOTE: We purposefully don't use "break;" in order to chain the divisions
-            /** @noinspection PhpMissingBreakStatementInspection */
-            // phpcs:disable PSR2.ControlStructures.SwitchDeclaration.TerminatingComment
-            case 'days':
-                $length_in_units /= 24;
-            /** @noinspection PhpMissingBreakStatementInspection */
-            case 'hours':
-                // fall through is intentional
-                $length_in_units /= 60;
-            /** @noinspection PhpMissingBreakStatementInspection */
-            case 'minutes':
-                // fall through is intentional
-                $length_in_units /= 60;
-            case 'seconds':
-            default:
-                $length_in_units = ceil($length_in_units);
-        }
-        // phpcs:enable
-        if ($round_up) {
-            $length_in_units = max($length_in_units, 1);
-        }
-        return $length_in_units;
-    }
-
-
-    /**
-     *        get end date and time
-     *
-     * @param string $dt_frmt   - string representation of date format defaults to 'F j, Y'
-     * @param string $tm_format - string representation of time format defaults to 'g:i a'
-     * @return    mixed                string on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function end_date_and_time($dt_frmt = '', $tm_format = '')
-    {
-        return $this->_show_datetime('', 'end', $dt_frmt, $tm_format);
-    }
-
-
-    /**
-     * @param string $dt_frmt
-     * @param string $tm_format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_end_date_and_time($dt_frmt = '', $tm_format = '')
-    {
-        $this->_show_datetime('', 'end', $dt_frmt, $tm_format, true);
-    }
-
-
-    /**
-     *        get start timestamp
-     *
-     * @return        int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function start()
-    {
-        return $this->get_raw('DTT_EVT_start');
-    }
-
-
-    /**
-     *        get end timestamp
-     *
-     * @return        int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function end()
-    {
-        return $this->get_raw('DTT_EVT_end');
-    }
-
-
-    /**
-     *    get the registration limit for this datetime slot
-     *
-     * @return        mixed        int on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function reg_limit()
-    {
-        return $this->get_raw('DTT_reg_limit');
-    }
-
-
-    /**
-     *    have the tickets sold for this datetime, met or exceed the registration limit ?
-     *
-     * @return        boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function sold_out()
-    {
-        return $this->reg_limit() > 0 && $this->sold() >= $this->reg_limit();
-    }
-
-
-    /**
-     * return the total number of spaces remaining at this venue.
-     * This only takes the venue's capacity into account, NOT the tickets available for sale
-     *
-     * @param bool $consider_tickets Whether to consider tickets remaining when determining if there are any spaces left
-     *                               Because if all tickets attached to this datetime have no spaces left,
-     *                               then this datetime IS effectively sold out.
-     *                               However, there are cases where we just want to know the spaces
-     *                               remaining for this particular datetime, hence the flag.
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function spaces_remaining($consider_tickets = false)
-    {
-        // tickets remaining available for purchase
-        // no need for special checks for infinite, because if DTT_reg_limit == EE_INF, then EE_INF - x = EE_INF
-        $dtt_remaining = $this->reg_limit() - $this->sold_and_reserved();
-        if (! $consider_tickets) {
-            return $dtt_remaining;
-        }
-        $tickets_remaining = $this->tickets_remaining();
-        return min($dtt_remaining, $tickets_remaining);
-    }
-
-
-    /**
-     * Counts the total tickets available
-     * (from all the different types of tickets which are available for this datetime).
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function tickets_remaining($query_params = array())
-    {
-        $sum = 0;
-        $tickets = $this->tickets($query_params);
-        if (! empty($tickets)) {
-            foreach ($tickets as $ticket) {
-                if ($ticket instanceof EE_Ticket) {
-                    // get the actual amount of tickets that can be sold
-                    $qty = $ticket->qty('saleable');
-                    if ($qty === EE_INF) {
-                        return EE_INF;
-                    }
-                    // no negative ticket quantities plz
-                    if ($qty > 0) {
-                        $sum += $qty;
-                    }
-                }
-            }
-        }
-        return $sum;
-    }
-
-
-    /**
-     * Gets the count of all the tickets available at this datetime (not ticket types)
-     * before any were sold
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function sum_tickets_initially_available($query_params = array())
-    {
-        return $this->sum_related('Ticket', $query_params, 'TKT_qty');
-    }
-
-
-    /**
-     * Returns the lesser-of-the two: spaces remaining at this datetime, or
-     * the total tickets remaining (a sum of the tickets remaining for each ticket type
-     * that is available for this datetime).
-     *
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function total_tickets_available_at_this_datetime()
-    {
-        return $this->spaces_remaining(true);
-    }
-
-
-    /**
-     * This simply compares the internal dtt for the given string with NOW
-     * and determines if the date is upcoming or not.
-     *
-     * @access public
-     * @return boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function is_upcoming()
-    {
-        return ($this->get_raw('DTT_EVT_start') > time());
-    }
-
-
-    /**
-     * This simply compares the internal datetime for the given string with NOW
-     * and returns if the date is active (i.e. start and end time)
-     *
-     * @return boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function is_active()
-    {
-        return ($this->get_raw('DTT_EVT_start') < time() && $this->get_raw('DTT_EVT_end') > time());
-    }
-
-
-    /**
-     * This simply compares the internal dtt for the given string with NOW
-     * and determines if the date is expired or not.
-     *
-     * @return boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function is_expired()
-    {
-        return ($this->get_raw('DTT_EVT_end') < time());
-    }
-
-
-    /**
-     * This returns the active status for whether an event is active, upcoming, or expired
-     *
-     * @return int return value will be one of the EE_Datetime status constants.
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_active_status()
-    {
-        $total_tickets_for_this_dtt = $this->total_tickets_available_at_this_datetime();
-        if ($total_tickets_for_this_dtt !== false && $total_tickets_for_this_dtt < 1) {
-            return EE_Datetime::sold_out;
-        }
-        if ($this->is_expired()) {
-            return EE_Datetime::expired;
-        }
-        if ($this->is_upcoming()) {
-            return EE_Datetime::upcoming;
-        }
-        if ($this->is_active()) {
-            return EE_Datetime::active;
-        }
-        return null;
-    }
-
-
-    /**
-     * This returns a nice display name for the datetime that is contingent on the span between the dates and times.
-     *
-     * @param  boolean $use_dtt_name if TRUE then we'll use DTT->name() if its not empty.
-     * @return string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_dtt_display_name($use_dtt_name = false)
-    {
-        if ($use_dtt_name) {
-            $dtt_name = $this->name();
-            if (! empty($dtt_name)) {
-                return $dtt_name;
-            }
-        }
-        // first condition is to see if the months are different
-        if (date('m', $this->get_raw('DTT_EVT_start')) !== date('m', $this->get_raw('DTT_EVT_end'))
-        ) {
-            $display_date = $this->start_date('M j\, Y g:i a') . ' - ' . $this->end_date('M j\, Y g:i a');
-            // next condition is if its the same month but different day
-        } else {
-            if (date('m', $this->get_raw('DTT_EVT_start')) === date('m', $this->get_raw('DTT_EVT_end'))
-                && date('d', $this->get_raw('DTT_EVT_start')) !== date('d', $this->get_raw('DTT_EVT_end'))
-            ) {
-                $display_date = $this->start_date('M j\, g:i a') . ' - ' . $this->end_date('M j\, g:i a Y');
-            } else {
-                $display_date = $this->start_date('F j\, Y')
-                                . ' @ '
-                                . $this->start_date('g:i a')
-                                . ' - '
-                                . $this->end_date('g:i a');
-            }
-        }
-        return $display_date;
-    }
-
-
-    /**
-     * Gets all the tickets for this datetime
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Base_Class[]|EE_Ticket[]
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function tickets($query_params = array())
-    {
-        return $this->get_many_related('Ticket', $query_params);
-    }
-
-
-    /**
-     * Gets all the ticket types currently available for purchase
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Ticket[]
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function ticket_types_available_for_purchase($query_params = array())
-    {
-        // first check if datetime is valid
-        if ($this->sold_out() || ! ($this->is_upcoming() || $this->is_active())) {
-            return array();
-        }
-        if (empty($query_params)) {
-            $query_params = array(
-                array(
-                    'TKT_start_date' => array('<=', EEM_Ticket::instance()->current_time_for_query('TKT_start_date')),
-                    'TKT_end_date'   => array('>=', EEM_Ticket::instance()->current_time_for_query('TKT_end_date')),
-                    'TKT_deleted'    => false,
-                ),
-            );
-        }
-        return $this->tickets($query_params);
-    }
-
-
-    /**
-     * @return EE_Base_Class|EE_Event
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function event()
-    {
-        return $this->get_first_related('Event');
-    }
-
-
-    /**
-     * Updates the DTT_sold attribute (and saves) based on the number of registrations for this datetime
-     * (via the tickets).
-     *
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function update_sold()
-    {
-        $count_regs_for_this_datetime = EEM_Registration::instance()->count(
-            array(
-                array(
-                    'STS_ID'                 => EEM_Registration::status_id_approved,
-                    'REG_deleted'            => 0,
-                    'Ticket.Datetime.DTT_ID' => $this->ID(),
-                ),
-            )
-        );
-        $this->set_sold($count_regs_for_this_datetime);
-        $this->save();
-        return $count_regs_for_this_datetime;
-    }
-
-
-    /*******************************************************************
+	/**
+	 * constant used by get_active_status, indicates datetime has no more available spaces
+	 */
+	const sold_out = 'DTS';
+
+	/**
+	 * constant used by get_active_status, indicating datetime is still active (even is not over, can be registered-for)
+	 */
+	const active = 'DTA';
+
+	/**
+	 * constant used by get_active_status, indicating the datetime cannot be used for registrations yet, but has not
+	 * expired
+	 */
+	const upcoming = 'DTU';
+
+	/**
+	 * Datetime is postponed
+	 */
+	const postponed = 'DTP';
+
+	/**
+	 * Datetime is cancelled
+	 */
+	const cancelled = 'DTC';
+
+	/**
+	 * constant used by get_active_status, indicates datetime has expired (event is over)
+	 */
+	const expired = 'DTE';
+
+	/**
+	 * constant used in various places indicating that an event is INACTIVE (not yet ready to be published)
+	 */
+	const inactive = 'DTI';
+
+
+	/**
+	 * @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  $date_formats      incoming date_formats in an array where the first value is the date_format
+	 *                                  and the second value is the time format
+	 * @return EE_Datetime
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public static function new_instance($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, $date_formats);
+	}
+
+
+	/**
+	 * @param array  $props_n_values  incoming values from the database
+	 * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
+	 *                                the website will be used.
+	 * @return EE_Datetime
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public static function new_instance_from_db($props_n_values = array(), $timezone = null)
+	{
+		return new self($props_n_values, true, $timezone);
+	}
+
+
+	/**
+	 * @param $name
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_name($name)
+	{
+		$this->set('DTT_name', $name);
+	}
+
+
+	/**
+	 * @param $description
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_description($description)
+	{
+		$this->set('DTT_description', $description);
+	}
+
+
+	/**
+	 * Set event start date
+	 * set the start date for an event
+	 *
+	 * @param string $date a string representation of the event's date ex:  Dec. 25, 2025 or 12-25-2025
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_start_date($date)
+	{
+		$this->_set_date_for($date, 'DTT_EVT_start');
+	}
+
+
+	/**
+	 * Set event start time
+	 * set the start time for an event
+	 *
+	 * @param string $time a string representation of the event time ex:  9am  or  7:30 PM
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_start_time($time)
+	{
+		$this->_set_time_for($time, 'DTT_EVT_start');
+	}
+
+
+	/**
+	 * Set event end date
+	 * set the end date for an event
+	 *
+	 * @param string $date a string representation of the event's date ex:  Dec. 25, 2025 or 12-25-2025
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_end_date($date)
+	{
+		$this->_set_date_for($date, 'DTT_EVT_end');
+	}
+
+
+	/**
+	 * Set event end time
+	 * set the end time for an event
+	 *
+	 * @param string $time a string representation of the event time ex:  9am  or  7:30 PM
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_end_time($time)
+	{
+		$this->_set_time_for($time, 'DTT_EVT_end');
+	}
+
+
+	/**
+	 * Set registration limit
+	 * set the maximum number of attendees that can be registered for this datetime slot
+	 *
+	 * @param int $reg_limit
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_reg_limit($reg_limit)
+	{
+		$this->set('DTT_reg_limit', $reg_limit);
+	}
+
+
+	/**
+	 * get the number of tickets sold for this datetime slot
+	 *
+	 * @return mixed int on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function sold()
+	{
+		return $this->get_raw('DTT_sold');
+	}
+
+
+	/**
+	 * @param int $sold
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_sold($sold)
+	{
+		// sold can not go below zero
+		$sold = max(0, $sold);
+		$this->set('DTT_sold', $sold);
+	}
+
+
+	/**
+	 * Increments sold by amount passed by $qty, and persists it immediately to the database.
+	 * Simultaneously decreases the reserved count, unless $also_decrease_reserved is false.
+	 *
+	 * @param int $qty
+	 * @param boolean $also_decrease_reserved
+	 * @return boolean indicating success
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function increaseSold($qty = 1, $also_decrease_reserved = true)
+	{
+		$qty = absint($qty);
+		if ($also_decrease_reserved) {
+			$success = $this->adjustNumericFieldsInDb(
+				[
+					'DTT_reserved' => $qty * -1,
+					'DTT_sold' => $qty
+				]
+			);
+		} else {
+			$success = $this->adjustNumericFieldsInDb(
+				[
+					'DTT_sold' => $qty
+				]
+			);
+		}
+
+		do_action(
+			'AHEE__EE_Datetime__increase_sold',
+			$this,
+			$qty,
+			$this->sold(),
+			$success
+		);
+		return $success;
+	}
+
+
+	/**
+	 * Decrements (subtracts) sold amount passed by $qty directly in the DB and on the model object. (Ie, no need
+	 * to save afterwards.)
+	 *
+	 * @param int $qty
+	 * @return boolean indicating success
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function decreaseSold($qty = 1)
+	{
+		$qty = absint($qty);
+		$success = $this->adjustNumericFieldsInDb(
+			[
+				'DTT_sold' => $qty * -1
+			]
+		);
+		do_action(
+			'AHEE__EE_Datetime__decrease_sold',
+			$this,
+			$qty,
+			$this->sold(),
+			$success
+		);
+		return $success;
+	}
+
+
+	/**
+	 * Gets qty of reserved tickets for this datetime
+	 *
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function reserved()
+	{
+		return $this->get_raw('DTT_reserved');
+	}
+
+
+	/**
+	 * Sets qty of reserved tickets for this datetime
+	 *
+	 * @param int $reserved
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_reserved($reserved)
+	{
+		// reserved can not go below zero
+		$reserved = max(0, (int) $reserved);
+		$this->set('DTT_reserved', $reserved);
+	}
+
+
+	/**
+	 * Increments reserved by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @param int $qty
+	 * @return boolean indicating success
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function increaseReserved($qty = 1)
+	{
+		$qty = absint($qty);
+		$success = $this->incrementFieldConditionallyInDb(
+			'DTT_reserved',
+			'DTT_sold',
+			'DTT_reg_limit',
+			$qty
+		);
+		do_action(
+			'AHEE__EE_Datetime__increase_reserved',
+			$this,
+			$qty,
+			$this->reserved(),
+			$success
+		);
+		return $success;
+	}
+
+
+	/**
+	 * Decrements (subtracts) reserved by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @param int $qty
+	 * @return boolean indicating success
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function decreaseReserved($qty = 1)
+	{
+		$qty = absint($qty);
+		$success = $this->adjustNumericFieldsInDb(
+			[
+				'DTT_reserved' => $qty * -1
+			]
+		);
+		do_action(
+			'AHEE__EE_Datetime__decrease_reserved',
+			$this,
+			$qty,
+			$this->reserved(),
+			$success
+		);
+		return $success;
+	}
+
+
+	/**
+	 * total sold and reserved tickets
+	 *
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function sold_and_reserved()
+	{
+		return $this->sold() + $this->reserved();
+	}
+
+
+	/**
+	 * returns the datetime name
+	 *
+	 * @return string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function name()
+	{
+		return $this->get('DTT_name');
+	}
+
+
+	/**
+	 * returns the datetime description
+	 *
+	 * @return string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function description()
+	{
+		return $this->get('DTT_description');
+	}
+
+
+	/**
+	 * This helper simply returns whether the event_datetime for the current datetime is a primary datetime
+	 *
+	 * @return boolean  TRUE if is primary, FALSE if not.
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function is_primary()
+	{
+		return $this->get('DTT_is_primary');
+	}
+
+
+	/**
+	 * This helper simply returns the order for the datetime
+	 *
+	 * @return int  The order of the datetime for this event.
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function order()
+	{
+		return $this->get('DTT_order');
+	}
+
+
+	/**
+	 * This helper simply returns the parent id for the datetime
+	 *
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function parent()
+	{
+		return $this->get('DTT_parent');
+	}
+
+
+	/**
+	 * show date and/or time
+	 *
+	 * @param string $date_or_time    whether to display a date or time or both
+	 * @param string $start_or_end    whether to display start or end datetimes
+	 * @param string $dt_frmt
+	 * @param string $tm_frmt
+	 * @param bool   $echo            whether we echo or return (note echoing uses "pretty" formats,
+	 *                                otherwise we use the standard formats)
+	 * @return string|bool  string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	private function _show_datetime(
+		$date_or_time = null,
+		$start_or_end = 'start',
+		$dt_frmt = '',
+		$tm_frmt = '',
+		$echo = false
+	) {
+		$field_name = "DTT_EVT_{$start_or_end}";
+		$dtt = $this->_get_datetime(
+			$field_name,
+			$dt_frmt,
+			$tm_frmt,
+			$date_or_time,
+			$echo
+		);
+		if (! $echo) {
+			return $dtt;
+		}
+		return '';
+	}
+
+
+	/**
+	 * get event start date.  Provide either the date format, or NULL to re-use the
+	 * last-used format, or '' to use the default date format
+	 *
+	 * @param string $dt_frmt string representation of date format defaults to 'F j, Y'
+	 * @return mixed            string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function start_date($dt_frmt = '')
+	{
+		return $this->_show_datetime('D', 'start', $dt_frmt);
+	}
+
+
+	/**
+	 * Echoes start_date()
+	 *
+	 * @param string $dt_frmt
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_start_date($dt_frmt = '')
+	{
+		$this->_show_datetime('D', 'start', $dt_frmt, null, true);
+	}
+
+
+	/**
+	 * get end date. Provide either the date format, or NULL to re-use the
+	 * last-used format, or '' to use the default date format
+	 *
+	 * @param string $dt_frmt string representation of date format defaults to 'F j, Y'
+	 * @return mixed            string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function end_date($dt_frmt = '')
+	{
+		return $this->_show_datetime('D', 'end', $dt_frmt);
+	}
+
+
+	/**
+	 * Echoes the end date. See end_date()
+	 *
+	 * @param string $dt_frmt
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_end_date($dt_frmt = '')
+	{
+		$this->_show_datetime('D', 'end', $dt_frmt, null, true);
+	}
+
+
+	/**
+	 * get date_range - meaning the start AND end date
+	 *
+	 * @access public
+	 * @param string $dt_frmt     string representation of date format defaults to WP settings
+	 * @param string $conjunction conjunction junction what's your function ?
+	 *                            this string joins the start date with the end date ie: Jan 01 "to" Dec 31
+	 * @return mixed              string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function date_range($dt_frmt = '', $conjunction = ' - ')
+	{
+		$dt_frmt = ! empty($dt_frmt) ? $dt_frmt : $this->_dt_frmt;
+		$start = str_replace(
+			' ',
+			'&nbsp;',
+			$this->get_i18n_datetime('DTT_EVT_start', $dt_frmt)
+		);
+		$end = str_replace(
+			' ',
+			'&nbsp;',
+			$this->get_i18n_datetime('DTT_EVT_end', $dt_frmt)
+		);
+		return $start !== $end ? $start . $conjunction . $end : $start;
+	}
+
+
+	/**
+	 * @param string $dt_frmt
+	 * @param string $conjunction
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_date_range($dt_frmt = '', $conjunction = ' - ')
+	{
+		echo $this->date_range($dt_frmt, $conjunction);
+	}
+
+
+	/**
+	 * get start time
+	 *
+	 * @param string $tm_format - string representation of time format defaults to 'g:i a'
+	 * @return mixed        string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function start_time($tm_format = '')
+	{
+		return $this->_show_datetime('T', 'start', null, $tm_format);
+	}
+
+
+	/**
+	 * @param string $tm_format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_start_time($tm_format = '')
+	{
+		$this->_show_datetime('T', 'start', null, $tm_format, true);
+	}
+
+
+	/**
+	 * get end time
+	 *
+	 * @param string $tm_format string representation of time format defaults to 'g:i a'
+	 * @return mixed                string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function end_time($tm_format = '')
+	{
+		return $this->_show_datetime('T', 'end', null, $tm_format);
+	}
+
+
+	/**
+	 * @param string $tm_format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_end_time($tm_format = '')
+	{
+		$this->_show_datetime('T', 'end', null, $tm_format, true);
+	}
+
+
+	/**
+	 * get time_range
+	 *
+	 * @access public
+	 * @param string $tm_format   string representation of time format defaults to 'g:i a'
+	 * @param string $conjunction conjunction junction what's your function ?
+	 *                            this string joins the start date with the end date ie: Jan 01 "to" Dec 31
+	 * @return mixed              string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function time_range($tm_format = '', $conjunction = ' - ')
+	{
+		$tm_format = ! empty($tm_format) ? $tm_format : $this->_tm_frmt;
+		$start = str_replace(
+			' ',
+			'&nbsp;',
+			$this->get_i18n_datetime('DTT_EVT_start', $tm_format)
+		);
+		$end = str_replace(
+			' ',
+			'&nbsp;',
+			$this->get_i18n_datetime('DTT_EVT_end', $tm_format)
+		);
+		return $start !== $end ? $start . $conjunction . $end : $start;
+	}
+
+
+	/**
+	 * @param string $tm_format
+	 * @param string $conjunction
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_time_range($tm_format = '', $conjunction = ' - ')
+	{
+		echo $this->time_range($tm_format, $conjunction);
+	}
+
+
+	/**
+	 * This returns a range representation of the date and times.
+	 * Output is dependent on the difference (or similarity) between DTT_EVT_start and DTT_EVT_end.
+	 * Also, the return value is localized.
+	 *
+	 * @param string $dt_format
+	 * @param string $tm_format
+	 * @param string $conjunction used between two different dates or times.
+	 *                            ex: Dec 1{$conjunction}}Dec 6, or 2pm{$conjunction}3pm
+	 * @param string $separator   used between the date and time formats.
+	 *                            ex: Dec 1, 2016{$separator}2pm
+	 * @return string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function date_and_time_range(
+		$dt_format = '',
+		$tm_format = '',
+		$conjunction = ' - ',
+		$separator = ' '
+	) {
+		$dt_format = ! empty($dt_format) ? $dt_format : $this->_dt_frmt;
+		$tm_format = ! empty($tm_format) ? $tm_format : $this->_tm_frmt;
+		$full_format = $dt_format . $separator . $tm_format;
+		// the range output depends on various conditions
+		switch (true) {
+			// start date timestamp and end date timestamp are the same.
+			case ($this->get_raw('DTT_EVT_start') === $this->get_raw('DTT_EVT_end')):
+				$output = $this->get_i18n_datetime('DTT_EVT_start', $full_format);
+				break;
+			// start and end date are the same but times are different
+			case ($this->start_date() === $this->end_date()):
+				$output = $this->get_i18n_datetime('DTT_EVT_start', $full_format)
+						  . $conjunction
+						  . $this->get_i18n_datetime('DTT_EVT_end', $tm_format);
+				break;
+			// all other conditions
+			default:
+				$output = $this->get_i18n_datetime('DTT_EVT_start', $full_format)
+						  . $conjunction
+						  . $this->get_i18n_datetime('DTT_EVT_end', $full_format);
+				break;
+		}
+		return $output;
+	}
+
+
+	/**
+	 * This echos the results of date and time range.
+	 *
+	 * @see date_and_time_range() for more details on purpose.
+	 * @param string $dt_format
+	 * @param string $tm_format
+	 * @param string $conjunction
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_date_and_time_range($dt_format = '', $tm_format = '', $conjunction = ' - ')
+	{
+		echo $this->date_and_time_range($dt_format, $tm_format, $conjunction);
+	}
+
+
+	/**
+	 * get start date and start time
+	 *
+	 * @param    string $dt_format - string representation of date format defaults to 'F j, Y'
+	 * @param    string $tm_format - string representation of time format defaults to 'g:i a'
+	 * @return    mixed    string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function start_date_and_time($dt_format = '', $tm_format = '')
+	{
+		return $this->_show_datetime('', 'start', $dt_format, $tm_format);
+	}
+
+
+	/**
+	 * @param string $dt_frmt
+	 * @param string $tm_format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_start_date_and_time($dt_frmt = '', $tm_format = '')
+	{
+		$this->_show_datetime('', 'start', $dt_frmt, $tm_format, true);
+	}
+
+
+	/**
+	 * Shows the length of the event (start to end time).
+	 * Can be shown in 'seconds','minutes','hours', or 'days'.
+	 * By default, rounds up. (So if you use 'days', and then event
+	 * only occurs for 1 hour, it will return 1 day).
+	 *
+	 * @param string $units 'seconds','minutes','hours','days'
+	 * @param bool   $round_up
+	 * @return float|int|mixed
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function length($units = 'seconds', $round_up = false)
+	{
+		$start = $this->get_raw('DTT_EVT_start');
+		$end = $this->get_raw('DTT_EVT_end');
+		$length_in_units = $end - $start;
+		switch ($units) {
+			// NOTE: We purposefully don't use "break;" in order to chain the divisions
+			/** @noinspection PhpMissingBreakStatementInspection */
+			// phpcs:disable PSR2.ControlStructures.SwitchDeclaration.TerminatingComment
+			case 'days':
+				$length_in_units /= 24;
+			/** @noinspection PhpMissingBreakStatementInspection */
+			case 'hours':
+				// fall through is intentional
+				$length_in_units /= 60;
+			/** @noinspection PhpMissingBreakStatementInspection */
+			case 'minutes':
+				// fall through is intentional
+				$length_in_units /= 60;
+			case 'seconds':
+			default:
+				$length_in_units = ceil($length_in_units);
+		}
+		// phpcs:enable
+		if ($round_up) {
+			$length_in_units = max($length_in_units, 1);
+		}
+		return $length_in_units;
+	}
+
+
+	/**
+	 *        get end date and time
+	 *
+	 * @param string $dt_frmt   - string representation of date format defaults to 'F j, Y'
+	 * @param string $tm_format - string representation of time format defaults to 'g:i a'
+	 * @return    mixed                string on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function end_date_and_time($dt_frmt = '', $tm_format = '')
+	{
+		return $this->_show_datetime('', 'end', $dt_frmt, $tm_format);
+	}
+
+
+	/**
+	 * @param string $dt_frmt
+	 * @param string $tm_format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_end_date_and_time($dt_frmt = '', $tm_format = '')
+	{
+		$this->_show_datetime('', 'end', $dt_frmt, $tm_format, true);
+	}
+
+
+	/**
+	 *        get start timestamp
+	 *
+	 * @return        int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function start()
+	{
+		return $this->get_raw('DTT_EVT_start');
+	}
+
+
+	/**
+	 *        get end timestamp
+	 *
+	 * @return        int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function end()
+	{
+		return $this->get_raw('DTT_EVT_end');
+	}
+
+
+	/**
+	 *    get the registration limit for this datetime slot
+	 *
+	 * @return        mixed        int on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function reg_limit()
+	{
+		return $this->get_raw('DTT_reg_limit');
+	}
+
+
+	/**
+	 *    have the tickets sold for this datetime, met or exceed the registration limit ?
+	 *
+	 * @return        boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function sold_out()
+	{
+		return $this->reg_limit() > 0 && $this->sold() >= $this->reg_limit();
+	}
+
+
+	/**
+	 * return the total number of spaces remaining at this venue.
+	 * This only takes the venue's capacity into account, NOT the tickets available for sale
+	 *
+	 * @param bool $consider_tickets Whether to consider tickets remaining when determining if there are any spaces left
+	 *                               Because if all tickets attached to this datetime have no spaces left,
+	 *                               then this datetime IS effectively sold out.
+	 *                               However, there are cases where we just want to know the spaces
+	 *                               remaining for this particular datetime, hence the flag.
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function spaces_remaining($consider_tickets = false)
+	{
+		// tickets remaining available for purchase
+		// no need for special checks for infinite, because if DTT_reg_limit == EE_INF, then EE_INF - x = EE_INF
+		$dtt_remaining = $this->reg_limit() - $this->sold_and_reserved();
+		if (! $consider_tickets) {
+			return $dtt_remaining;
+		}
+		$tickets_remaining = $this->tickets_remaining();
+		return min($dtt_remaining, $tickets_remaining);
+	}
+
+
+	/**
+	 * Counts the total tickets available
+	 * (from all the different types of tickets which are available for this datetime).
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function tickets_remaining($query_params = array())
+	{
+		$sum = 0;
+		$tickets = $this->tickets($query_params);
+		if (! empty($tickets)) {
+			foreach ($tickets as $ticket) {
+				if ($ticket instanceof EE_Ticket) {
+					// get the actual amount of tickets that can be sold
+					$qty = $ticket->qty('saleable');
+					if ($qty === EE_INF) {
+						return EE_INF;
+					}
+					// no negative ticket quantities plz
+					if ($qty > 0) {
+						$sum += $qty;
+					}
+				}
+			}
+		}
+		return $sum;
+	}
+
+
+	/**
+	 * Gets the count of all the tickets available at this datetime (not ticket types)
+	 * before any were sold
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function sum_tickets_initially_available($query_params = array())
+	{
+		return $this->sum_related('Ticket', $query_params, 'TKT_qty');
+	}
+
+
+	/**
+	 * Returns the lesser-of-the two: spaces remaining at this datetime, or
+	 * the total tickets remaining (a sum of the tickets remaining for each ticket type
+	 * that is available for this datetime).
+	 *
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function total_tickets_available_at_this_datetime()
+	{
+		return $this->spaces_remaining(true);
+	}
+
+
+	/**
+	 * This simply compares the internal dtt for the given string with NOW
+	 * and determines if the date is upcoming or not.
+	 *
+	 * @access public
+	 * @return boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function is_upcoming()
+	{
+		return ($this->get_raw('DTT_EVT_start') > time());
+	}
+
+
+	/**
+	 * This simply compares the internal datetime for the given string with NOW
+	 * and returns if the date is active (i.e. start and end time)
+	 *
+	 * @return boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function is_active()
+	{
+		return ($this->get_raw('DTT_EVT_start') < time() && $this->get_raw('DTT_EVT_end') > time());
+	}
+
+
+	/**
+	 * This simply compares the internal dtt for the given string with NOW
+	 * and determines if the date is expired or not.
+	 *
+	 * @return boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function is_expired()
+	{
+		return ($this->get_raw('DTT_EVT_end') < time());
+	}
+
+
+	/**
+	 * This returns the active status for whether an event is active, upcoming, or expired
+	 *
+	 * @return int return value will be one of the EE_Datetime status constants.
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_active_status()
+	{
+		$total_tickets_for_this_dtt = $this->total_tickets_available_at_this_datetime();
+		if ($total_tickets_for_this_dtt !== false && $total_tickets_for_this_dtt < 1) {
+			return EE_Datetime::sold_out;
+		}
+		if ($this->is_expired()) {
+			return EE_Datetime::expired;
+		}
+		if ($this->is_upcoming()) {
+			return EE_Datetime::upcoming;
+		}
+		if ($this->is_active()) {
+			return EE_Datetime::active;
+		}
+		return null;
+	}
+
+
+	/**
+	 * This returns a nice display name for the datetime that is contingent on the span between the dates and times.
+	 *
+	 * @param  boolean $use_dtt_name if TRUE then we'll use DTT->name() if its not empty.
+	 * @return string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_dtt_display_name($use_dtt_name = false)
+	{
+		if ($use_dtt_name) {
+			$dtt_name = $this->name();
+			if (! empty($dtt_name)) {
+				return $dtt_name;
+			}
+		}
+		// first condition is to see if the months are different
+		if (date('m', $this->get_raw('DTT_EVT_start')) !== date('m', $this->get_raw('DTT_EVT_end'))
+		) {
+			$display_date = $this->start_date('M j\, Y g:i a') . ' - ' . $this->end_date('M j\, Y g:i a');
+			// next condition is if its the same month but different day
+		} else {
+			if (date('m', $this->get_raw('DTT_EVT_start')) === date('m', $this->get_raw('DTT_EVT_end'))
+				&& date('d', $this->get_raw('DTT_EVT_start')) !== date('d', $this->get_raw('DTT_EVT_end'))
+			) {
+				$display_date = $this->start_date('M j\, g:i a') . ' - ' . $this->end_date('M j\, g:i a Y');
+			} else {
+				$display_date = $this->start_date('F j\, Y')
+								. ' @ '
+								. $this->start_date('g:i a')
+								. ' - '
+								. $this->end_date('g:i a');
+			}
+		}
+		return $display_date;
+	}
+
+
+	/**
+	 * Gets all the tickets for this datetime
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Base_Class[]|EE_Ticket[]
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function tickets($query_params = array())
+	{
+		return $this->get_many_related('Ticket', $query_params);
+	}
+
+
+	/**
+	 * Gets all the ticket types currently available for purchase
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Ticket[]
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function ticket_types_available_for_purchase($query_params = array())
+	{
+		// first check if datetime is valid
+		if ($this->sold_out() || ! ($this->is_upcoming() || $this->is_active())) {
+			return array();
+		}
+		if (empty($query_params)) {
+			$query_params = array(
+				array(
+					'TKT_start_date' => array('<=', EEM_Ticket::instance()->current_time_for_query('TKT_start_date')),
+					'TKT_end_date'   => array('>=', EEM_Ticket::instance()->current_time_for_query('TKT_end_date')),
+					'TKT_deleted'    => false,
+				),
+			);
+		}
+		return $this->tickets($query_params);
+	}
+
+
+	/**
+	 * @return EE_Base_Class|EE_Event
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function event()
+	{
+		return $this->get_first_related('Event');
+	}
+
+
+	/**
+	 * Updates the DTT_sold attribute (and saves) based on the number of registrations for this datetime
+	 * (via the tickets).
+	 *
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function update_sold()
+	{
+		$count_regs_for_this_datetime = EEM_Registration::instance()->count(
+			array(
+				array(
+					'STS_ID'                 => EEM_Registration::status_id_approved,
+					'REG_deleted'            => 0,
+					'Ticket.Datetime.DTT_ID' => $this->ID(),
+				),
+			)
+		);
+		$this->set_sold($count_regs_for_this_datetime);
+		$this->save();
+		return $count_regs_for_this_datetime;
+	}
+
+
+	/*******************************************************************
      ***********************  DEPRECATED METHODS  **********************
      *******************************************************************/
 
 
-    /**
-     * Increments sold by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function increase_sold($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Datetime::increaseSold() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        return $this->increaseSold($qty);
-    }
-
-
-    /**
-     * Decrements (subtracts) sold amount passed by $qty directly in the DB and on the model object. (Ie, no need
-     * to save afterwards.)
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function decrease_sold($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Datetime::decreaseSold() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        return $this->decreaseSold($qty);
-    }
-
-
-    /**
-     * Increments reserved by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return boolean indicating success
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function increase_reserved($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Datetime::increaseReserved() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        return $this->increaseReserved($qty);
-    }
-
-
-    /**
-     * Decrements (subtracts) reserved by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function decrease_reserved($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Datetime::decreaseReserved() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        return $this->decreaseReserved($qty);
-    }
+	/**
+	 * Increments sold by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function increase_sold($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Datetime::increaseSold() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		return $this->increaseSold($qty);
+	}
+
+
+	/**
+	 * Decrements (subtracts) sold amount passed by $qty directly in the DB and on the model object. (Ie, no need
+	 * to save afterwards.)
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function decrease_sold($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Datetime::decreaseSold() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		return $this->decreaseSold($qty);
+	}
+
+
+	/**
+	 * Increments reserved by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return boolean indicating success
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function increase_reserved($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Datetime::increaseReserved() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		return $this->increaseReserved($qty);
+	}
+
+
+	/**
+	 * Decrements (subtracts) reserved by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function decrease_reserved($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Datetime::decreaseReserved() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		return $this->decreaseReserved($qty);
+	}
 }

core/db_classes/EE_Base_Class.class.php

Indentation +3330 added lines, -3330 removed lines

@@ -13,3345 +13,3345 @@
 abstract class EE_Base_Class
 {
 
-    /**
-     * This is an array of the original properties and values provided during construction
-     * of this model object. (keys are model field names, values are their values).
-     * This list is important to remember so that when we are merging data from the db, we know
-     * which values to override and which to not override.
-     *
-     * @var array
-     */
-    protected $_props_n_values_provided_in_constructor;
-
-    /**
-     * Timezone
-     * This gets set by the "set_timezone()" method so that we know what timezone incoming strings|timestamps are in.
-     * This can also be used before a get to set what timezone you want strings coming out of the object to be in.  NOT
-     * all EE_Base_Class child classes use this property but any that use a EE_Datetime_Field data type will have
-     * access to it.
-     *
-     * @var string
-     */
-    protected $_timezone;
-
-    /**
-     * date format
-     * pattern or format for displaying dates
-     *
-     * @var string $_dt_frmt
-     */
-    protected $_dt_frmt;
-
-    /**
-     * time format
-     * pattern or format for displaying time
-     *
-     * @var string $_tm_frmt
-     */
-    protected $_tm_frmt;
-
-    /**
-     * This property is for holding a cached array of object properties indexed by property name as the key.
-     * The purpose of this is for setting a cache on properties that may have calculated values after a
-     * prepare_for_get.  That way the cache can be checked first and the calculated property returned instead of having
-     * to recalculate. Used by _set_cached_property() and _get_cached_property() methods.
-     *
-     * @var array
-     */
-    protected $_cached_properties = array();
-
-    /**
-     * An array containing keys of the related model, and values are either an array of related mode objects or a
-     * single
-     * related model object. see the model's _model_relations. The keys should match those specified. And if the
-     * relation is of type EE_Belongs_To (or one of its children), then there should only be ONE related model object,
-     * all others have an array)
-     *
-     * @var array
-     */
-    protected $_model_relations = array();
-
-    /**
-     * Array where keys are field names (see the model's _fields property) and values are their values. To see what
-     * their types should be, look at what that field object returns on its prepare_for_get and prepare_for_set methods)
-     *
-     * @var array
-     */
-    protected $_fields = array();
-
-    /**
-     * @var boolean indicating whether or not this model object is intended to ever be saved
-     * For example, we might create model objects intended to only be used for the duration
-     * of this request and to be thrown away, and if they were accidentally saved
-     * it would be a bug.
-     */
-    protected $_allow_persist = true;
-
-    /**
-     * @var boolean indicating whether or not this model object's properties have changed since construction
-     */
-    protected $_has_changes = false;
-
-    /**
-     * @var EEM_Base
-     */
-    protected $_model;
-
-    /**
-     * This is a cache of results from custom selections done on a query that constructs this entity. The only purpose
-     * for these values is for retrieval of the results, they are not further queryable and they are not persisted to
-     * the db.  They also do not automatically update if there are any changes to the data that produced their results.
-     * The format is a simple array of field_alias => field_value.  So for instance if a custom select was something
-     * like,  "Select COUNT(Registration.REG_ID) as Registration_Count ...", then the resulting value will be in this
-     * array as:
-     * array(
-     *  'Registration_Count' => 24
-     * );
-     * Note: if the custom select configuration for the query included a data type, the value will be in the data type
-     * provided for the query (@see EventEspresso\core\domain\values\model\CustomSelects::__construct phpdocs for more
-     * info)
-     *
-     * @var array
-     */
-    protected $custom_selection_results = array();
-
-
-    /**
-     * basic constructor for Event Espresso classes, performs any necessary initialization, and verifies it's children
-     * play nice
-     *
-     * @param array   $fieldValues                             where each key is a field (ie, array key in the 2nd
-     *                                                         layer of the model's _fields array, (eg, EVT_ID,
-     *                                                         TXN_amount, QST_name, etc) and values are their values
-     * @param boolean $bydb                                    a flag for setting if the class is instantiated by the
-     *                                                         corresponding db model or not.
-     * @param string  $timezone                                indicate what timezone you want any datetime fields to
-     *                                                         be in when instantiating a EE_Base_Class object.
-     * @param array   $date_formats                            An array of date formats to set on construct where first
-     *                                                         value is the date_format and second value is the time
-     *                                                         format.
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function __construct($fieldValues = array(), $bydb = false, $timezone = '', $date_formats = array())
-    {
-        $className = get_class($this);
-        do_action("AHEE__{$className}__construct", $this, $fieldValues);
-        $model = $this->get_model();
-        $model_fields = $model->field_settings(false);
-        // ensure $fieldValues is an array
-        $fieldValues = is_array($fieldValues) ? $fieldValues : array($fieldValues);
-        // verify client code has not passed any invalid field names
-        foreach ($fieldValues as $field_name => $field_value) {
-            if (! isset($model_fields[ $field_name ])) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Invalid field (%s) passed to constructor of %s. Allowed fields are :%s',
-                            'event_espresso'
-                        ),
-                        $field_name,
-                        get_class($this),
-                        implode(', ', array_keys($model_fields))
-                    )
-                );
-            }
-        }
-        $this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
-        if (! empty($date_formats) && is_array($date_formats)) {
-            list($this->_dt_frmt, $this->_tm_frmt) = $date_formats;
-        } else {
-            // set default formats for date and time
-            $this->_dt_frmt = (string) get_option('date_format', 'Y-m-d');
-            $this->_tm_frmt = (string) get_option('time_format', 'g:i a');
-        }
-        // if db model is instantiating
-        if ($bydb) {
-            // client code has indicated these field values are from the database
-            foreach ($model_fields as $fieldName => $field) {
-                $this->set_from_db(
-                    $fieldName,
-                    isset($fieldValues[ $fieldName ]) ? $fieldValues[ $fieldName ] : null
-                );
-            }
-        } else {
-            // we're constructing a brand
-            // new instance of the model object. Generally, this means we'll need to do more field validation
-            foreach ($model_fields as $fieldName => $field) {
-                $this->set(
-                    $fieldName,
-                    isset($fieldValues[ $fieldName ]) ? $fieldValues[ $fieldName ] : null,
-                    true
-                );
-            }
-        }
-        // remember what values were passed to this constructor
-        $this->_props_n_values_provided_in_constructor = $fieldValues;
-        // remember in entity mapper
-        if (! $bydb && $model->has_primary_key_field() && $this->ID()) {
-            $model->add_to_entity_map($this);
-        }
-        // setup all the relations
-        foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                $this->_model_relations[ $relation_name ] = null;
-            } else {
-                $this->_model_relations[ $relation_name ] = array();
-            }
-        }
-        /**
-         * Action done at the end of each model object construction
-         *
-         * @param EE_Base_Class $this the model object just created
-         */
-        do_action('AHEE__EE_Base_Class__construct__finished', $this);
-    }
-
-
-    /**
-     * Gets whether or not this model object is allowed to persist/be saved to the database.
-     *
-     * @return boolean
-     */
-    public function allow_persist()
-    {
-        return $this->_allow_persist;
-    }
-
-
-    /**
-     * Sets whether or not this model object should be allowed to be saved to the DB.
-     * Normally once this is set to FALSE you wouldn't set it back to TRUE, unless
-     * you got new information that somehow made you change your mind.
-     *
-     * @param boolean $allow_persist
-     * @return boolean
-     */
-    public function set_allow_persist($allow_persist)
-    {
-        return $this->_allow_persist = $allow_persist;
-    }
-
-
-    /**
-     * Gets the field's original value when this object was constructed during this request.
-     * This can be helpful when determining if a model object has changed or not
-     *
-     * @param string $field_name
-     * @return mixed|null
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_original($field_name)
-    {
-        if (isset($this->_props_n_values_provided_in_constructor[ $field_name ])
-            && $field_settings = $this->get_model()->field_settings_for($field_name)
-        ) {
-            return $field_settings->prepare_for_get($this->_props_n_values_provided_in_constructor[ $field_name ]);
-        }
-        return null;
-    }
-
-
-    /**
-     * @param EE_Base_Class $obj
-     * @return string
-     */
-    public function get_class($obj)
-    {
-        return get_class($obj);
-    }
-
-
-    /**
-     * Overrides parent because parent expects old models.
-     * This also doesn't do any validation, and won't work for serialized arrays
-     *
-     * @param    string $field_name
-     * @param    mixed  $field_value
-     * @param bool      $use_default
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws ReflectionException
-     * @throws ReflectionException
-     */
-    public function set($field_name, $field_value, $use_default = false)
-    {
-        // if not using default and nothing has changed, and object has already been setup (has ID),
-        // then don't do anything
-        if (! $use_default
-            && $this->_fields[ $field_name ] === $field_value
-            && $this->ID()
-        ) {
-            return;
-        }
-        $model = $this->get_model();
-        $this->_has_changes = true;
-        $field_obj = $model->field_settings_for($field_name);
-        if ($field_obj instanceof EE_Model_Field_Base) {
-            // if ( method_exists( $field_obj, 'set_timezone' )) {
-            if ($field_obj instanceof EE_Datetime_Field) {
-                $field_obj->set_timezone($this->_timezone);
-                $field_obj->set_date_format($this->_dt_frmt);
-                $field_obj->set_time_format($this->_tm_frmt);
-            }
-            $holder_of_value = $field_obj->prepare_for_set($field_value);
-            // should the value be null?
-            if (($field_value === null || $holder_of_value === null || $holder_of_value === '') && $use_default) {
-                $this->_fields[ $field_name ] = $field_obj->get_default_value();
-                /**
-                 * To save having to refactor all the models, if a default value is used for a
-                 * EE_Datetime_Field, and that value is not null nor is it a DateTime
-                 * object.  Then let's do a set again to ensure that it becomes a DateTime
-                 * object.
-                 *
-                 * @since 4.6.10+
-                 */
-                if ($field_obj instanceof EE_Datetime_Field
-                    && $this->_fields[ $field_name ] !== null
-                    && ! $this->_fields[ $field_name ] instanceof DateTime
-                ) {
-                    empty($this->_fields[ $field_name ])
-                        ? $this->set($field_name, time())
-                        : $this->set($field_name, $this->_fields[ $field_name ]);
-                }
-            } else {
-                $this->_fields[ $field_name ] = $holder_of_value;
-            }
-            // if we're not in the constructor...
-            // now check if what we set was a primary key
-            if (// note: props_n_values_provided_in_constructor is only set at the END of the constructor
-                $this->_props_n_values_provided_in_constructor
-                && $field_value
-                && $field_name === $model->primary_key_name()
-            ) {
-                // if so, we want all this object's fields to be filled either with
-                // what we've explicitly set on this model
-                // or what we have in the db
-                // echo "setting primary key!";
-                $fields_on_model = self::_get_model(get_class($this))->field_settings();
-                $obj_in_db = self::_get_model(get_class($this))->get_one_by_ID($field_value);
-                foreach ($fields_on_model as $field_obj) {
-                    if (! array_key_exists($field_obj->get_name(), $this->_props_n_values_provided_in_constructor)
-                        && $field_obj->get_name() !== $field_name
-                    ) {
-                        $this->set($field_obj->get_name(), $obj_in_db->get($field_obj->get_name()));
-                    }
-                }
-                // oh this model object has an ID? well make sure its in the entity mapper
-                $model->add_to_entity_map($this);
-            }
-            // let's unset any cache for this field_name from the $_cached_properties property.
-            $this->_clear_cached_property($field_name);
-        } else {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'A valid EE_Model_Field_Base could not be found for the given field name: %s',
-                        'event_espresso'
-                    ),
-                    $field_name
-                )
-            );
-        }
-    }
-
-
-    /**
-     * Set custom select values for model.
-     *
-     * @param array $custom_select_values
-     */
-    public function setCustomSelectsValues(array $custom_select_values)
-    {
-        $this->custom_selection_results = $custom_select_values;
-    }
-
-
-    /**
-     * Returns the custom select value for the provided alias if its set.
-     * If not set, returns null.
-     *
-     * @param string $alias
-     * @return string|int|float|null
-     */
-    public function getCustomSelect($alias)
-    {
-        return isset($this->custom_selection_results[ $alias ])
-            ? $this->custom_selection_results[ $alias ]
-            : null;
-    }
-
-
-    /**
-     * This sets the field value on the db column if it exists for the given $column_name or
-     * saves it to EE_Extra_Meta if the given $column_name does not match a db column.
-     *
-     * @see EE_message::get_column_value for related documentation on the necessity of this method.
-     * @param string $field_name  Must be the exact column name.
-     * @param mixed  $field_value The value to set.
-     * @return int|bool @see EE_Base_Class::update_extra_meta() for return docs.
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_field_or_extra_meta($field_name, $field_value)
-    {
-        if ($this->get_model()->has_field($field_name)) {
-            $this->set($field_name, $field_value);
-            return true;
-        }
-        // ensure this object is saved first so that extra meta can be properly related.
-        $this->save();
-        return $this->update_extra_meta($field_name, $field_value);
-    }
-
-
-    /**
-     * This retrieves the value of the db column set on this class or if that's not present
-     * it will attempt to retrieve from extra_meta if found.
-     * Example Usage:
-     * Via EE_Message child class:
-     * Due to the dynamic nature of the EE_messages system, EE_messengers will always have a "to",
-     * "from", "subject", and "content" field (as represented in the EE_Message schema), however they may
-     * also have additional main fields specific to the messenger.  The system accommodates those extra
-     * fields through the EE_Extra_Meta table.  This method allows for EE_messengers to retrieve the
-     * value for those extra fields dynamically via the EE_message object.
-     *
-     * @param  string $field_name expecting the fully qualified field name.
-     * @return mixed|null  value for the field if found.  null if not found.
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_field_or_extra_meta($field_name)
-    {
-        if ($this->get_model()->has_field($field_name)) {
-            $column_value = $this->get($field_name);
-        } else {
-            // This isn't a column in the main table, let's see if it is in the extra meta.
-            $column_value = $this->get_extra_meta($field_name, true, null);
-        }
-        return $column_value;
-    }
-
-
-    /**
-     * See $_timezone property for description of what the timezone property is for.  This SETS the timezone internally
-     * for being able to reference what timezone we are running conversions on when converting TO the internal timezone
-     * (UTC Unix Timestamp) for the object OR when converting FROM the internal timezone (UTC Unix Timestamp). This is
-     * available to all child classes that may be using the EE_Datetime_Field for a field data type.
-     *
-     * @access public
-     * @param string $timezone A valid timezone string as described by @link http://www.php.net/manual/en/timezones.php
-     * @return void
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_timezone($timezone = '')
-    {
-        $this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
-        // make sure we clear all cached properties because they won't be relevant now
-        $this->_clear_cached_properties();
-        // make sure we update field settings and the date for all EE_Datetime_Fields
-        $model_fields = $this->get_model()->field_settings(false);
-        foreach ($model_fields as $field_name => $field_obj) {
-            if ($field_obj instanceof EE_Datetime_Field) {
-                $field_obj->set_timezone($this->_timezone);
-                if (isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime) {
-                    EEH_DTT_Helper::setTimezone($this->_fields[ $field_name ], new DateTimeZone($this->_timezone));
-                }
-            }
-        }
-    }
-
-
-    /**
-     * This just returns whatever is set for the current timezone.
-     *
-     * @access public
-     * @return string timezone string
-     */
-    public function get_timezone()
-    {
-        return $this->_timezone;
-    }
-
-
-    /**
-     * This sets the internal date format to what is sent in to be used as the new default for the class
-     * internally instead of wp set date format options
-     *
-     * @since 4.6
-     * @param string $format should be a format recognizable by PHP date() functions.
-     */
-    public function set_date_format($format)
-    {
-        $this->_dt_frmt = $format;
-        // clear cached_properties because they won't be relevant now.
-        $this->_clear_cached_properties();
-    }
-
-
-    /**
-     * This sets the internal time format string to what is sent in to be used as the new default for the
-     * class internally instead of wp set time format options.
-     *
-     * @since 4.6
-     * @param string $format should be a format recognizable by PHP date() functions.
-     */
-    public function set_time_format($format)
-    {
-        $this->_tm_frmt = $format;
-        // clear cached_properties because they won't be relevant now.
-        $this->_clear_cached_properties();
-    }
-
-
-    /**
-     * This returns the current internal set format for the date and time formats.
-     *
-     * @param bool $full           if true (default), then return the full format.  Otherwise will return an array
-     *                             where the first value is the date format and the second value is the time format.
-     * @return mixed string|array
-     */
-    public function get_format($full = true)
-    {
-        return $full ? $this->_dt_frmt . ' ' . $this->_tm_frmt : array($this->_dt_frmt, $this->_tm_frmt);
-    }
-
-
-    /**
-     * cache
-     * stores the passed model object on the current model object.
-     * In certain circumstances, we can use this cached model object instead of querying for another one entirely.
-     *
-     * @param string        $relationName    one of the keys in the _model_relations array on the model. Eg
-     *                                       'Registration' associated with this model object
-     * @param EE_Base_Class $object_to_cache that has a relation to this model object. (Eg, if this is a Transaction,
-     *                                       that could be a payment or a registration)
-     * @param null          $cache_id        a string or number that will be used as the key for any Belongs_To_Many
-     *                                       items which will be stored in an array on this object
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return mixed    index into cache, or just TRUE if the relation is of type Belongs_To (because there's only one
-     *                                       related thing, no array)
-     */
-    public function cache($relationName = '', $object_to_cache = null, $cache_id = null)
-    {
-        // its entirely possible that there IS no related object yet in which case there is nothing to cache.
-        if (! $object_to_cache instanceof EE_Base_Class) {
-            return false;
-        }
-        // also get "how" the object is related, or throw an error
-        if (! $relationship_to_model = $this->get_model()->related_settings_for($relationName)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__('There is no relationship to %s on a %s. Cannot cache it', 'event_espresso'),
-                    $relationName,
-                    get_class($this)
-                )
-            );
-        }
-        // how many things are related ?
-        if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
-            // if it's a "belongs to" relationship, then there's only one related model object
-            // eg, if this is a registration, there's only 1 attendee for it
-            // so for these model objects just set it to be cached
-            $this->_model_relations[ $relationName ] = $object_to_cache;
-            $return = true;
-        } else {
-            // otherwise, this is the "many" side of a one to many relationship,
-            // so we'll add the object to the array of related objects for that type.
-            // eg: if this is an event, there are many registrations for that event,
-            // so we cache the registrations in an array
-            if (! is_array($this->_model_relations[ $relationName ])) {
-                // if for some reason, the cached item is a model object,
-                // then stick that in the array, otherwise start with an empty array
-                $this->_model_relations[ $relationName ] = $this->_model_relations[ $relationName ]
-                                                           instanceof
-                                                           EE_Base_Class
-                    ? array($this->_model_relations[ $relationName ]) : array();
-            }
-            // first check for a cache_id which is normally empty
-            if (! empty($cache_id)) {
-                // if the cache_id exists, then it means we are purposely trying to cache this
-                // with a known key that can then be used to retrieve the object later on
-                $this->_model_relations[ $relationName ][ $cache_id ] = $object_to_cache;
-                $return = $cache_id;
-            } elseif ($object_to_cache->ID()) {
-                // OR the cached object originally came from the db, so let's just use it's PK for an ID
-                $this->_model_relations[ $relationName ][ $object_to_cache->ID() ] = $object_to_cache;
-                $return = $object_to_cache->ID();
-            } else {
-                // OR it's a new object with no ID, so just throw it in the array with an auto-incremented ID
-                $this->_model_relations[ $relationName ][] = $object_to_cache;
-                // move the internal pointer to the end of the array
-                end($this->_model_relations[ $relationName ]);
-                // and grab the key so that we can return it
-                $return = key($this->_model_relations[ $relationName ]);
-            }
-        }
-        return $return;
-    }
-
-
-    /**
-     * For adding an item to the cached_properties property.
-     *
-     * @access protected
-     * @param string      $fieldname the property item the corresponding value is for.
-     * @param mixed       $value     The value we are caching.
-     * @param string|null $cache_type
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _set_cached_property($fieldname, $value, $cache_type = null)
-    {
-        // first make sure this property exists
-        $this->get_model()->field_settings_for($fieldname);
-        $cache_type = empty($cache_type) ? 'standard' : $cache_type;
-        $this->_cached_properties[ $fieldname ][ $cache_type ] = $value;
-    }
-
-
-    /**
-     * This returns the value cached property if it exists OR the actual property value if the cache doesn't exist.
-     * This also SETS the cache if we return the actual property!
-     *
-     * @param string $fieldname        the name of the property we're trying to retrieve
-     * @param bool   $pretty
-     * @param string $extra_cache_ref  This allows the user to specify an extra cache ref for the given property
-     *                                 (in cases where the same property may be used for different outputs
-     *                                 - i.e. datetime, money etc.)
-     *                                 It can also accept certain pre-defined "schema" strings
-     *                                 to define how to output the property.
-     *                                 see the field's prepare_for_pretty_echoing for what strings can be used
-     * @return mixed                   whatever the value for the property is we're retrieving
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _get_cached_property($fieldname, $pretty = false, $extra_cache_ref = null)
-    {
-        // verify the field exists
-        $model = $this->get_model();
-        $model->field_settings_for($fieldname);
-        $cache_type = $pretty ? 'pretty' : 'standard';
-        $cache_type .= ! empty($extra_cache_ref) ? '_' . $extra_cache_ref : '';
-        if (isset($this->_cached_properties[ $fieldname ][ $cache_type ])) {
-            return $this->_cached_properties[ $fieldname ][ $cache_type ];
-        }
-        $value = $this->_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
-        $this->_set_cached_property($fieldname, $value, $cache_type);
-        return $value;
-    }
-
-
-    /**
-     * If the cache didn't fetch the needed item, this fetches it.
-     *
-     * @param string $fieldname
-     * @param bool   $pretty
-     * @param string $extra_cache_ref
-     * @return mixed
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _get_fresh_property($fieldname, $pretty = false, $extra_cache_ref = null)
-    {
-        $field_obj = $this->get_model()->field_settings_for($fieldname);
-        // If this is an EE_Datetime_Field we need to make sure timezone, formats, and output are correct
-        if ($field_obj instanceof EE_Datetime_Field) {
-            $this->_prepare_datetime_field($field_obj, $pretty, $extra_cache_ref);
-        }
-        if (! isset($this->_fields[ $fieldname ])) {
-            $this->_fields[ $fieldname ] = null;
-        }
-        $value = $pretty
-            ? $field_obj->prepare_for_pretty_echoing($this->_fields[ $fieldname ], $extra_cache_ref)
-            : $field_obj->prepare_for_get($this->_fields[ $fieldname ]);
-        return $value;
-    }
-
-
-    /**
-     * set timezone, formats, and output for EE_Datetime_Field objects
-     *
-     * @param \EE_Datetime_Field $datetime_field
-     * @param bool               $pretty
-     * @param null               $date_or_time
-     * @return void
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _prepare_datetime_field(
-        EE_Datetime_Field $datetime_field,
-        $pretty = false,
-        $date_or_time = null
-    ) {
-        $datetime_field->set_timezone($this->_timezone);
-        $datetime_field->set_date_format($this->_dt_frmt, $pretty);
-        $datetime_field->set_time_format($this->_tm_frmt, $pretty);
-        // set the output returned
-        switch ($date_or_time) {
-            case 'D':
-                $datetime_field->set_date_time_output('date');
-                break;
-            case 'T':
-                $datetime_field->set_date_time_output('time');
-                break;
-            default:
-                $datetime_field->set_date_time_output();
-        }
-    }
-
-
-    /**
-     * This just takes care of clearing out the cached_properties
-     *
-     * @return void
-     */
-    protected function _clear_cached_properties()
-    {
-        $this->_cached_properties = array();
-    }
-
-
-    /**
-     * This just clears out ONE property if it exists in the cache
-     *
-     * @param  string $property_name the property to remove if it exists (from the _cached_properties array)
-     * @return void
-     */
-    protected function _clear_cached_property($property_name)
-    {
-        if (isset($this->_cached_properties[ $property_name ])) {
-            unset($this->_cached_properties[ $property_name ]);
-        }
-    }
-
-
-    /**
-     * Ensures that this related thing is a model object.
-     *
-     * @param mixed  $object_or_id EE_base_Class/int/string either a related model object, or its ID
-     * @param string $model_name   name of the related thing, eg 'Attendee',
-     * @return EE_Base_Class
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function ensure_related_thing_is_model_obj($object_or_id, $model_name)
-    {
-        $other_model_instance = self::_get_model_instance_with_name(
-            self::_get_model_classname($model_name),
-            $this->_timezone
-        );
-        return $other_model_instance->ensure_is_obj($object_or_id);
-    }
-
-
-    /**
-     * Forgets the cached model of the given relation Name. So the next time we request it,
-     * we will fetch it again from the database. (Handy if you know it's changed somehow).
-     * If a specific object is supplied, and the relationship to it is either a HasMany or HABTM,
-     * then only remove that one object from our cached array. Otherwise, clear the entire list
-     *
-     * @param string $relationName                         one of the keys in the _model_relations array on the model.
-     *                                                     Eg 'Registration'
-     * @param mixed  $object_to_remove_or_index_into_array or an index into the array of cached things, or NULL
-     *                                                     if you intend to use $clear_all = TRUE, or the relation only
-     *                                                     has 1 object anyways (ie, it's a BelongsToRelation)
-     * @param bool   $clear_all                            This flags clearing the entire cache relation property if
-     *                                                     this is HasMany or HABTM.
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return EE_Base_Class | boolean from which was cleared from the cache, or true if we requested to remove a
-     *                                                     relation from all
-     */
-    public function clear_cache($relationName, $object_to_remove_or_index_into_array = null, $clear_all = false)
-    {
-        $relationship_to_model = $this->get_model()->related_settings_for($relationName);
-        $index_in_cache = '';
-        if (! $relationship_to_model) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__('There is no relationship to %s on a %s. Cannot clear that cache', 'event_espresso'),
-                    $relationName,
-                    get_class($this)
-                )
-            );
-        }
-        if ($clear_all) {
-            $obj_removed = true;
-            $this->_model_relations[ $relationName ] = null;
-        } elseif ($relationship_to_model instanceof EE_Belongs_To_Relation) {
-            $obj_removed = $this->_model_relations[ $relationName ];
-            $this->_model_relations[ $relationName ] = null;
-        } else {
-            if ($object_to_remove_or_index_into_array instanceof EE_Base_Class
-                && $object_to_remove_or_index_into_array->ID()
-            ) {
-                $index_in_cache = $object_to_remove_or_index_into_array->ID();
-                if (is_array($this->_model_relations[ $relationName ])
-                    && ! isset($this->_model_relations[ $relationName ][ $index_in_cache ])
-                ) {
-                    $index_found_at = null;
-                    // find this object in the array even though it has a different key
-                    foreach ($this->_model_relations[ $relationName ] as $index => $obj) {
-                        /** @noinspection TypeUnsafeComparisonInspection */
-                        if ($obj instanceof EE_Base_Class
-                            && (
-                                $obj == $object_to_remove_or_index_into_array
-                                || $obj->ID() === $object_to_remove_or_index_into_array->ID()
-                            )
-                        ) {
-                            $index_found_at = $index;
-                            break;
-                        }
-                    }
-                    if ($index_found_at) {
-                        $index_in_cache = $index_found_at;
-                    } else {
-                        // it wasn't found. huh. well obviously it doesn't need to be removed from teh cache
-                        // if it wasn't in it to begin with. So we're done
-                        return $object_to_remove_or_index_into_array;
-                    }
-                }
-            } elseif ($object_to_remove_or_index_into_array instanceof EE_Base_Class) {
-                // so they provided a model object, but it's not yet saved to the DB... so let's go hunting for it!
-                foreach ($this->get_all_from_cache($relationName) as $index => $potentially_obj_we_want) {
-                    /** @noinspection TypeUnsafeComparisonInspection */
-                    if ($potentially_obj_we_want == $object_to_remove_or_index_into_array) {
-                        $index_in_cache = $index;
-                    }
-                }
-            } else {
-                $index_in_cache = $object_to_remove_or_index_into_array;
-            }
-            // supposedly we've found it. But it could just be that the client code
-            // provided a bad index/object
-            if (isset($this->_model_relations[ $relationName ][ $index_in_cache ])) {
-                $obj_removed = $this->_model_relations[ $relationName ][ $index_in_cache ];
-                unset($this->_model_relations[ $relationName ][ $index_in_cache ]);
-            } else {
-                // that thing was never cached anyways.
-                $obj_removed = null;
-            }
-        }
-        return $obj_removed;
-    }
-
-
-    /**
-     * update_cache_after_object_save
-     * Allows a cached item to have it's cache ID (within the array of cached items) reset using the new ID it has
-     * obtained after being saved to the db
-     *
-     * @param string        $relationName       - the type of object that is cached
-     * @param EE_Base_Class $newly_saved_object - the newly saved object to be re-cached
-     * @param string        $current_cache_id   - the ID that was used when originally caching the object
-     * @return boolean TRUE on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function update_cache_after_object_save(
-        $relationName,
-        EE_Base_Class $newly_saved_object,
-        $current_cache_id = ''
-    ) {
-        // verify that incoming object is of the correct type
-        $obj_class = 'EE_' . $relationName;
-        if ($newly_saved_object instanceof $obj_class) {
-            /* @type EE_Base_Class $newly_saved_object */
-            // now get the type of relation
-            $relationship_to_model = $this->get_model()->related_settings_for($relationName);
-            // if this is a 1:1 relationship
-            if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
-                // then just replace the cached object with the newly saved object
-                $this->_model_relations[ $relationName ] = $newly_saved_object;
-                return true;
-                // or if it's some kind of sordid feral polyamorous relationship...
-            }
-            if (is_array($this->_model_relations[ $relationName ])
-                && isset($this->_model_relations[ $relationName ][ $current_cache_id ])
-            ) {
-                // then remove the current cached item
-                unset($this->_model_relations[ $relationName ][ $current_cache_id ]);
-                // and cache the newly saved object using it's new ID
-                $this->_model_relations[ $relationName ][ $newly_saved_object->ID() ] = $newly_saved_object;
-                return true;
-            }
-        }
-        return false;
-    }
-
-
-    /**
-     * Fetches a single EE_Base_Class on that relation. (If the relation is of type
-     * BelongsTo, it will only ever have 1 object. However, other relations could have an array of objects)
-     *
-     * @param string $relationName
-     * @return EE_Base_Class
-     */
-    public function get_one_from_cache($relationName)
-    {
-        $cached_array_or_object = isset($this->_model_relations[ $relationName ])
-            ? $this->_model_relations[ $relationName ]
-            : null;
-        if (is_array($cached_array_or_object)) {
-            return array_shift($cached_array_or_object);
-        }
-        return $cached_array_or_object;
-    }
-
-
-    /**
-     * Fetches a single EE_Base_Class on that relation. (If the relation is of type
-     * BelongsTo, it will only ever have 1 object. However, other relations could have an array of objects)
-     *
-     * @param string $relationName
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return EE_Base_Class[] NOT necessarily indexed by primary keys
-     */
-    public function get_all_from_cache($relationName)
-    {
-        $objects = isset($this->_model_relations[ $relationName ]) ? $this->_model_relations[ $relationName ] : array();
-        // if the result is not an array, but exists, make it an array
-        $objects = is_array($objects) ? $objects : array($objects);
-        // bugfix for https://events.codebasehq.com/projects/event-espresso/tickets/7143
-        // basically, if this model object was stored in the session, and these cached model objects
-        // already have IDs, let's make sure they're in their model's entity mapper
-        // otherwise we will have duplicates next time we call
-        // EE_Registry::instance()->load_model( $relationName )->get_one_by_ID( $result->ID() );
-        $model = EE_Registry::instance()->load_model($relationName);
-        foreach ($objects as $model_object) {
-            if ($model instanceof EEM_Base && $model_object instanceof EE_Base_Class) {
-                // ensure its in the map if it has an ID; otherwise it will be added to the map when its saved
-                if ($model_object->ID()) {
-                    $model->add_to_entity_map($model_object);
-                }
-            } else {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Error retrieving related model objects. Either $1%s is not a model or $2%s is not a model object',
-                            'event_espresso'
-                        ),
-                        $relationName,
-                        gettype($model_object)
-                    )
-                );
-            }
-        }
-        return $objects;
-    }
-
-
-    /**
-     * Returns the next x number of EE_Base_Class objects in sequence from this object as found in the database
-     * matching the given query conditions.
-     *
-     * @param null  $field_to_order_by  What field is being used as the reference point.
-     * @param int   $limit              How many objects to return.
-     * @param array $query_params       Any additional conditions on the query.
-     * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
-     *                                  you can indicate just the columns you want returned
-     * @return array|EE_Base_Class[]
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function next_x($field_to_order_by = null, $limit = 1, $query_params = array(), $columns_to_select = null)
-    {
-        $model = $this->get_model();
-        $field = empty($field_to_order_by) && $model->has_primary_key_field()
-            ? $model->get_primary_key_field()->get_name()
-            : $field_to_order_by;
-        $current_value = ! empty($field) ? $this->get($field) : null;
-        if (empty($field) || empty($current_value)) {
-            return array();
-        }
-        return $model->next_x($current_value, $field, $limit, $query_params, $columns_to_select);
-    }
-
-
-    /**
-     * Returns the previous x number of EE_Base_Class objects in sequence from this object as found in the database
-     * matching the given query conditions.
-     *
-     * @param null  $field_to_order_by  What field is being used as the reference point.
-     * @param int   $limit              How many objects to return.
-     * @param array $query_params       Any additional conditions on the query.
-     * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
-     *                                  you can indicate just the columns you want returned
-     * @return array|EE_Base_Class[]
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function previous_x(
-        $field_to_order_by = null,
-        $limit = 1,
-        $query_params = array(),
-        $columns_to_select = null
-    ) {
-        $model = $this->get_model();
-        $field = empty($field_to_order_by) && $model->has_primary_key_field()
-            ? $model->get_primary_key_field()->get_name()
-            : $field_to_order_by;
-        $current_value = ! empty($field) ? $this->get($field) : null;
-        if (empty($field) || empty($current_value)) {
-            return array();
-        }
-        return $model->previous_x($current_value, $field, $limit, $query_params, $columns_to_select);
-    }
-
-
-    /**
-     * Returns the next EE_Base_Class object in sequence from this object as found in the database
-     * matching the given query conditions.
-     *
-     * @param null  $field_to_order_by  What field is being used as the reference point.
-     * @param array $query_params       Any additional conditions on the query.
-     * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
-     *                                  you can indicate just the columns you want returned
-     * @return array|EE_Base_Class
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function next($field_to_order_by = null, $query_params = array(), $columns_to_select = null)
-    {
-        $model = $this->get_model();
-        $field = empty($field_to_order_by) && $model->has_primary_key_field()
-            ? $model->get_primary_key_field()->get_name()
-            : $field_to_order_by;
-        $current_value = ! empty($field) ? $this->get($field) : null;
-        if (empty($field) || empty($current_value)) {
-            return array();
-        }
-        return $model->next($current_value, $field, $query_params, $columns_to_select);
-    }
-
-
-    /**
-     * Returns the previous EE_Base_Class object in sequence from this object as found in the database
-     * matching the given query conditions.
-     *
-     * @param null  $field_to_order_by  What field is being used as the reference point.
-     * @param array $query_params       Any additional conditions on the query.
-     * @param null  $columns_to_select  If left null, then an EE_Base_Class object is returned, otherwise
-     *                                  you can indicate just the column you want returned
-     * @return array|EE_Base_Class
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function previous($field_to_order_by = null, $query_params = array(), $columns_to_select = null)
-    {
-        $model = $this->get_model();
-        $field = empty($field_to_order_by) && $model->has_primary_key_field()
-            ? $model->get_primary_key_field()->get_name()
-            : $field_to_order_by;
-        $current_value = ! empty($field) ? $this->get($field) : null;
-        if (empty($field) || empty($current_value)) {
-            return array();
-        }
-        return $model->previous($current_value, $field, $query_params, $columns_to_select);
-    }
-
-
-    /**
-     * Overrides parent because parent expects old models.
-     * This also doesn't do any validation, and won't work for serialized arrays
-     *
-     * @param string $field_name
-     * @param mixed  $field_value_from_db
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_from_db($field_name, $field_value_from_db)
-    {
-        $field_obj = $this->get_model()->field_settings_for($field_name);
-        if ($field_obj instanceof EE_Model_Field_Base) {
-            // you would think the DB has no NULLs for non-null label fields right? wrong!
-            // eg, a CPT model object could have an entry in the posts table, but no
-            // entry in the meta table. Meaning that all its columns in the meta table
-            // are null! yikes! so when we find one like that, use defaults for its meta columns
-            if ($field_value_from_db === null) {
-                if ($field_obj->is_nullable()) {
-                    // if the field allows nulls, then let it be null
-                    $field_value = null;
-                } else {
-                    $field_value = $field_obj->get_default_value();
-                }
-            } else {
-                $field_value = $field_obj->prepare_for_set_from_db($field_value_from_db);
-            }
-            $this->_fields[ $field_name ] = $field_value;
-            $this->_clear_cached_property($field_name);
-        }
-    }
-
-
-    /**
-     * verifies that the specified field is of the correct type
-     *
-     * @param string $field_name
-     * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
-     *                                (in cases where the same property may be used for different outputs
-     *                                - i.e. datetime, money etc.)
-     * @return mixed
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get($field_name, $extra_cache_ref = null)
-    {
-        return $this->_get_cached_property($field_name, false, $extra_cache_ref);
-    }
-
-
-    /**
-     * This method simply returns the RAW unprocessed value for the given property in this class
-     *
-     * @param  string $field_name A valid fieldname
-     * @return mixed              Whatever the raw value stored on the property is.
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error if fieldSettings is misconfigured or the field doesn't exist.
-     */
-    public function get_raw($field_name)
-    {
-        $field_settings = $this->get_model()->field_settings_for($field_name);
-        return $field_settings instanceof EE_Datetime_Field && $this->_fields[ $field_name ] instanceof DateTime
-            ? $this->_fields[ $field_name ]->format('U')
-            : $this->_fields[ $field_name ];
-    }
-
-
-    /**
-     * This is used to return the internal DateTime object used for a field that is a
-     * EE_Datetime_Field.
-     *
-     * @param string $field_name               The field name retrieving the DateTime object.
-     * @return mixed null | false | DateTime  If the requested field is NOT a EE_Datetime_Field then
-     * @throws EE_Error an error is set and false returned.  If the field IS an
-     *                                         EE_Datetime_Field and but the field value is null, then
-     *                                         just null is returned (because that indicates that likely
-     *                                         this field is nullable).
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_DateTime_object($field_name)
-    {
-        $field_settings = $this->get_model()->field_settings_for($field_name);
-        if (! $field_settings instanceof EE_Datetime_Field) {
-            EE_Error::add_error(
-                sprintf(
-                    esc_html__(
-                        'The field %s is not an EE_Datetime_Field field.  There is no DateTime object stored on this field type.',
-                        'event_espresso'
-                    ),
-                    $field_name
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return false;
-        }
-        return isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime
-            ? clone $this->_fields[ $field_name ]
-            : null;
-    }
-
-
-    /**
-     * To be used in template to immediately echo out the value, and format it for output.
-     * Eg, should call stripslashes and whatnot before echoing
-     *
-     * @param string $field_name      the name of the field as it appears in the DB
-     * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
-     *                                (in cases where the same property may be used for different outputs
-     *                                - i.e. datetime, money etc.)
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e($field_name, $extra_cache_ref = null)
-    {
-        echo $this->get_pretty($field_name, $extra_cache_ref);
-    }
-
-
-    /**
-     * Exactly like e(), echoes out the field, but sets its schema to 'form_input', so that it
-     * can be easily used as the value of form input.
-     *
-     * @param string $field_name
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function f($field_name)
-    {
-        $this->e($field_name, 'form_input');
-    }
-
-
-    /**
-     * Same as `f()` but just returns the value instead of echoing it
-     *
-     * @param string $field_name
-     * @return string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_f($field_name)
-    {
-        return (string) $this->get_pretty($field_name, 'form_input');
-    }
-
-
-    /**
-     * Gets a pretty view of the field's value. $extra_cache_ref can specify different formats for this.
-     * The $extra_cache_ref will be passed to the model field's prepare_for_pretty_echoing, so consult the field's class
-     * to see what options are available.
-     *
-     * @param string $field_name
-     * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
-     *                                (in cases where the same property may be used for different outputs
-     *                                - i.e. datetime, money etc.)
-     * @return mixed
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_pretty($field_name, $extra_cache_ref = null)
-    {
-        return $this->_get_cached_property($field_name, true, $extra_cache_ref);
-    }
-
-
-    /**
-     * This simply returns the datetime for the given field name
-     * Note: this protected function is called by the wrapper get_date or get_time or get_datetime functions
-     * (and the equivalent e_date, e_time, e_datetime).
-     *
-     * @access   protected
-     * @param string   $field_name   Field on the instantiated EE_Base_Class child object
-     * @param string   $dt_frmt      valid datetime format used for date
-     *                               (if '' then we just use the default on the field,
-     *                               if NULL we use the last-used format)
-     * @param string   $tm_frmt      Same as above except this is for time format
-     * @param string   $date_or_time if NULL then both are returned, otherwise "D" = only date and "T" = only time.
-     * @param  boolean $echo         Whether the dtt is echoing using pretty echoing or just returned using vanilla get
-     * @return string|bool|EE_Error string on success, FALSE on fail, or EE_Error Exception is thrown
-     *                               if field is not a valid dtt field, or void if echoing
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _get_datetime($field_name, $dt_frmt = '', $tm_frmt = '', $date_or_time = '', $echo = false)
-    {
-        // clear cached property
-        $this->_clear_cached_property($field_name);
-        // reset format properties because they are used in get()
-        $this->_dt_frmt = $dt_frmt !== '' ? $dt_frmt : $this->_dt_frmt;
-        $this->_tm_frmt = $tm_frmt !== '' ? $tm_frmt : $this->_tm_frmt;
-        if ($echo) {
-            $this->e($field_name, $date_or_time);
-            return '';
-        }
-        return $this->get($field_name, $date_or_time);
-    }
-
-
-    /**
-     * below are wrapper functions for the various datetime outputs that can be obtained for JUST returning the date
-     * portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
-     * other echoes the pretty value for dtt)
-     *
-     * @param  string $field_name name of model object datetime field holding the value
-     * @param  string $format     format for the date returned (if NULL we use default in dt_frmt property)
-     * @return string            datetime value formatted
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_date($field_name, $format = '')
-    {
-        return $this->_get_datetime($field_name, $format, null, 'D');
-    }
-
-
-    /**
-     * @param        $field_name
-     * @param string $format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_date($field_name, $format = '')
-    {
-        $this->_get_datetime($field_name, $format, null, 'D', true);
-    }
-
-
-    /**
-     * below are wrapper functions for the various datetime outputs that can be obtained for JUST returning the time
-     * portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
-     * other echoes the pretty value for dtt)
-     *
-     * @param  string $field_name name of model object datetime field holding the value
-     * @param  string $format     format for the time returned ( if NULL we use default in tm_frmt property)
-     * @return string             datetime value formatted
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_time($field_name, $format = '')
-    {
-        return $this->_get_datetime($field_name, null, $format, 'T');
-    }
-
-
-    /**
-     * @param        $field_name
-     * @param string $format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_time($field_name, $format = '')
-    {
-        $this->_get_datetime($field_name, null, $format, 'T', true);
-    }
-
-
-    /**
-     * below are wrapper functions for the various datetime outputs that can be obtained for returning the date AND
-     * time portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
-     * other echoes the pretty value for dtt)
-     *
-     * @param  string $field_name name of model object datetime field holding the value
-     * @param  string $dt_frmt    format for the date returned (if NULL we use default in dt_frmt property)
-     * @param  string $tm_frmt    format for the time returned (if NULL we use default in tm_frmt property)
-     * @return string             datetime value formatted
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_datetime($field_name, $dt_frmt = '', $tm_frmt = '')
-    {
-        return $this->_get_datetime($field_name, $dt_frmt, $tm_frmt);
-    }
-
-
-    /**
-     * @param string $field_name
-     * @param string $dt_frmt
-     * @param string $tm_frmt
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_datetime($field_name, $dt_frmt = '', $tm_frmt = '')
-    {
-        $this->_get_datetime($field_name, $dt_frmt, $tm_frmt, null, true);
-    }
-
-
-    /**
-     * Get the i8ln value for a date using the WordPress @see date_i18n function.
-     *
-     * @param string $field_name The EE_Datetime_Field reference for the date being retrieved.
-     * @param string $format     PHP valid date/time string format.  If none is provided then the internal set format
-     *                           on the object will be used.
-     * @return string Date and time string in set locale or false if no field exists for the given
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     *                           field name.
-     */
-    public function get_i18n_datetime($field_name, $format = '')
-    {
-        $format = empty($format) ? $this->_dt_frmt . ' ' . $this->_tm_frmt : $format;
-        return date_i18n(
-            $format,
-            EEH_DTT_Helper::get_timestamp_with_offset(
-                $this->get_raw($field_name),
-                $this->_timezone
-            )
-        );
-    }
-
-
-    /**
-     * This method validates whether the given field name is a valid field on the model object as well as it is of a
-     * type EE_Datetime_Field.  On success there will be returned the field settings.  On fail an EE_Error exception is
-     * thrown.
-     *
-     * @param  string $field_name The field name being checked
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return EE_Datetime_Field
-     */
-    protected function _get_dtt_field_settings($field_name)
-    {
-        $field = $this->get_model()->field_settings_for($field_name);
-        // check if field is dtt
-        if ($field instanceof EE_Datetime_Field) {
-            return $field;
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    'The field name "%s" has been requested for the EE_Base_Class datetime functions and it is not a valid EE_Datetime_Field.  Please check the spelling of the field and make sure it has been setup as a EE_Datetime_Field in the %s model constructor',
-                    'event_espresso'
-                ),
-                $field_name,
-                self::_get_model_classname(get_class($this))
-            )
-        );
-    }
-
-
-
-
-    /**
-     * NOTE ABOUT BELOW:
-     * These convenience date and time setters are for setting date and time independently.  In other words you might
-     * want to change the time on a datetime_field but leave the date the same (or vice versa). IF on the other hand
-     * you want to set both date and time at the same time, you can just use the models default set($fieldname,$value)
-     * method and make sure you send the entire datetime value for setting.
-     */
-    /**
-     * sets the time on a datetime property
-     *
-     * @access protected
-     * @param string|Datetime $time      a valid time string for php datetime functions (or DateTime object)
-     * @param string          $fieldname the name of the field the time is being set on (must match a EE_Datetime_Field)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _set_time_for($time, $fieldname)
-    {
-        $this->_set_date_time('T', $time, $fieldname);
-    }
-
-
-    /**
-     * sets the date on a datetime property
-     *
-     * @access protected
-     * @param string|DateTime $date      a valid date string for php datetime functions ( or DateTime object)
-     * @param string          $fieldname the name of the field the date is being set on (must match a EE_Datetime_Field)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _set_date_for($date, $fieldname)
-    {
-        $this->_set_date_time('D', $date, $fieldname);
-    }
-
-
-    /**
-     * This takes care of setting a date or time independently on a given model object property. This method also
-     * verifies that the given fieldname matches a model object property and is for a EE_Datetime_Field field
-     *
-     * @access protected
-     * @param string          $what           "T" for time, 'B' for both, 'D' for Date.
-     * @param string|DateTime $datetime_value A valid Date or Time string (or DateTime object)
-     * @param string          $fieldname      the name of the field the date OR time is being set on (must match a
-     *                                        EE_Datetime_Field property)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _set_date_time($what = 'T', $datetime_value, $fieldname)
-    {
-        $field = $this->_get_dtt_field_settings($fieldname);
-        $field->set_timezone($this->_timezone);
-        $field->set_date_format($this->_dt_frmt);
-        $field->set_time_format($this->_tm_frmt);
-        switch ($what) {
-            case 'T':
-                $this->_fields[ $fieldname ] = $field->prepare_for_set_with_new_time(
-                    $datetime_value,
-                    $this->_fields[ $fieldname ]
-                );
-                break;
-            case 'D':
-                $this->_fields[ $fieldname ] = $field->prepare_for_set_with_new_date(
-                    $datetime_value,
-                    $this->_fields[ $fieldname ]
-                );
-                break;
-            case 'B':
-                $this->_fields[ $fieldname ] = $field->prepare_for_set($datetime_value);
-                break;
-        }
-        $this->_clear_cached_property($fieldname);
-    }
-
-
-    /**
-     * This will return a timestamp for the website timezone but ONLY when the current website timezone is different
-     * than the timezone set for the website. NOTE, this currently only works well with methods that return values.  If
-     * you use it with methods that echo values the $_timestamp property may not get reset to its original value and
-     * that could lead to some unexpected results!
-     *
-     * @access public
-     * @param string $field_name               This is the name of the field on the object that contains the date/time
-     *                                         value being returned.
-     * @param string $callback                 must match a valid method in this class (defaults to get_datetime)
-     * @param mixed (array|string) $args       This is the arguments that will be passed to the callback.
-     * @param string $prepend                  You can include something to prepend on the timestamp
-     * @param string $append                   You can include something to append on the timestamp
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return string timestamp
-     */
-    public function display_in_my_timezone(
-        $field_name,
-        $callback = 'get_datetime',
-        $args = null,
-        $prepend = '',
-        $append = ''
-    ) {
-        $timezone = EEH_DTT_Helper::get_timezone();
-        if ($timezone === $this->_timezone) {
-            return '';
-        }
-        $original_timezone = $this->_timezone;
-        $this->set_timezone($timezone);
-        $fn = (array) $field_name;
-        $args = array_merge($fn, (array) $args);
-        if (! method_exists($this, $callback)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'The method named "%s" given as the callback param in "display_in_my_timezone" does not exist.  Please check your spelling',
-                        'event_espresso'
-                    ),
-                    $callback
-                )
-            );
-        }
-        $args = (array) $args;
-        $return = $prepend . call_user_func_array(array($this, $callback), $args) . $append;
-        $this->set_timezone($original_timezone);
-        return $return;
-    }
-
-
-    /**
-     * Deletes this model object.
-     * This calls the `EE_Base_Class::_delete` method.  Child classes wishing to change default behaviour should
-     * override
-     * `EE_Base_Class::_delete` NOT this class.
-     *
-     * @return boolean | int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function delete()
-    {
-        /**
-         * Called just before the `EE_Base_Class::_delete` method call.
-         * Note:
-         * `EE_Base_Class::_delete` might be overridden by child classes so any client code hooking into these actions
-         * should be aware that `_delete` may not always result in a permanent delete.
-         * For example, `EE_Soft_Delete_Base_Class::_delete`
-         * soft deletes (trash) the object and does not permanently delete it.
-         *
-         * @param EE_Base_Class $model_object about to be 'deleted'
-         */
-        do_action('AHEE__EE_Base_Class__delete__before', $this);
-        $result = $this->_delete();
-        /**
-         * Called just after the `EE_Base_Class::_delete` method call.
-         * Note:
-         * `EE_Base_Class::_delete` might be overridden by child classes so any client code hooking into these actions
-         * should be aware that `_delete` may not always result in a permanent delete.
-         * For example `EE_Soft_Base_Class::_delete`
-         * soft deletes (trash) the object and does not permanently delete it.
-         *
-         * @param EE_Base_Class $model_object that was just 'deleted'
-         * @param boolean       $result
-         */
-        do_action('AHEE__EE_Base_Class__delete__end', $this, $result);
-        return $result;
-    }
-
-
-    /**
-     * Calls the specific delete method for the instantiated class.
-     * This method is called by the public `EE_Base_Class::delete` method.  Any child classes desiring to override
-     * default functionality for "delete" (which is to call `permanently_delete`) should override this method NOT
-     * `EE_Base_Class::delete`
-     *
-     * @return bool|int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _delete()
-    {
-        return $this->delete_permanently();
-    }
-
-
-    /**
-     * Deletes this model object permanently from db
-     * (but keep in mind related models may block the delete and return an error)
-     *
-     * @return bool | int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function delete_permanently()
-    {
-        /**
-         * Called just before HARD deleting a model object
-         *
-         * @param EE_Base_Class $model_object about to be 'deleted'
-         */
-        do_action('AHEE__EE_Base_Class__delete_permanently__before', $this);
-        $model = $this->get_model();
-        $result = $model->delete_permanently_by_ID($this->ID());
-        $this->refresh_cache_of_related_objects();
-        /**
-         * Called just after HARD deleting a model object
-         *
-         * @param EE_Base_Class $model_object that was just 'deleted'
-         * @param boolean       $result
-         */
-        do_action('AHEE__EE_Base_Class__delete_permanently__end', $this, $result);
-        return $result;
-    }
-
-
-    /**
-     * When this model object is deleted, it may still be cached on related model objects. This clears the cache of
-     * related model objects
-     *
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function refresh_cache_of_related_objects()
-    {
-        $model = $this->get_model();
-        foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if (! empty($this->_model_relations[ $relation_name ])) {
-                $related_objects = $this->_model_relations[ $relation_name ];
-                if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                    // this relation only stores a single model object, not an array
-                    // but let's make it consistent
-                    $related_objects = array($related_objects);
-                }
-                foreach ($related_objects as $related_object) {
-                    // only refresh their cache if they're in memory
-                    if ($related_object instanceof EE_Base_Class) {
-                        $related_object->clear_cache(
-                            $model->get_this_model_name(),
-                            $this
-                        );
-                    }
-                }
-            }
-        }
-    }
-
-
-    /**
-     *        Saves this object to the database. An array may be supplied to set some values on this
-     * object just before saving.
-     *
-     * @access public
-     * @param array $set_cols_n_values keys are field names, values are their new values,
-     *                                 if provided during the save() method (often client code will change the fields'
-     *                                 values before calling save)
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return int , 1 on a successful update, the ID of the new entry on insert; 0 on failure or if the model object
-     *                                 isn't allowed to persist (as determined by EE_Base_Class::allow_persist())
-     * @throws ReflectionException
-     * @throws ReflectionException
-     * @throws ReflectionException
-     */
-    public function save($set_cols_n_values = array())
-    {
-        $model = $this->get_model();
-        /**
-         * Filters the fields we're about to save on the model object
-         *
-         * @param array         $set_cols_n_values
-         * @param EE_Base_Class $model_object
-         */
-        $set_cols_n_values = (array) apply_filters(
-            'FHEE__EE_Base_Class__save__set_cols_n_values',
-            $set_cols_n_values,
-            $this
-        );
-        // set attributes as provided in $set_cols_n_values
-        foreach ($set_cols_n_values as $column => $value) {
-            $this->set($column, $value);
-        }
-        // no changes ? then don't do anything
-        if (! $this->_has_changes && $this->ID() && $model->get_primary_key_field()->is_auto_increment()) {
-            return 0;
-        }
-        /**
-         * Saving a model object.
-         * Before we perform a save, this action is fired.
-         *
-         * @param EE_Base_Class $model_object the model object about to be saved.
-         */
-        do_action('AHEE__EE_Base_Class__save__begin', $this);
-        if (! $this->allow_persist()) {
-            return 0;
-        }
-        // now get current attribute values
-        $save_cols_n_values = $this->_fields;
-        // if the object already has an ID, update it. Otherwise, insert it
-        // also: change the assumption about values passed to the model NOT being prepare dby the model object.
-        // They have been
-        $old_assumption_concerning_value_preparation = $model
-            ->get_assumption_concerning_values_already_prepared_by_model_object();
-        $model->assume_values_already_prepared_by_model_object(true);
-        // does this model have an autoincrement PK?
-        if ($model->has_primary_key_field()) {
-            if ($model->get_primary_key_field()->is_auto_increment()) {
-                // ok check if it's set, if so: update; if not, insert
-                if (! empty($save_cols_n_values[ $model->primary_key_name() ])) {
-                    $results = $model->update_by_ID($save_cols_n_values, $this->ID());
-                } else {
-                    unset($save_cols_n_values[ $model->primary_key_name() ]);
-                    $results = $model->insert($save_cols_n_values);
-                    if ($results) {
-                        // if successful, set the primary key
-                        // but don't use the normal SET method, because it will check if
-                        // an item with the same ID exists in the mapper & db, then
-                        // will find it in the db (because we just added it) and THAT object
-                        // will get added to the mapper before we can add this one!
-                        // but if we just avoid using the SET method, all that headache can be avoided
-                        $pk_field_name = $model->primary_key_name();
-                        $this->_fields[ $pk_field_name ] = $results;
-                        $this->_clear_cached_property($pk_field_name);
-                        $model->add_to_entity_map($this);
-                        $this->_update_cached_related_model_objs_fks();
-                    }
-                }
-            } else {// PK is NOT auto-increment
-                // so check if one like it already exists in the db
-                if ($model->exists_by_ID($this->ID())) {
-                    if (WP_DEBUG && ! $this->in_entity_map()) {
-                        throw new EE_Error(
-                            sprintf(
-                                esc_html__(
-                                    'Using a model object %1$s that is NOT in the entity map, can lead to unexpected errors. You should either: %4$s 1. Put it in the entity mapper by calling %2$s %4$s 2. Discard this model object and use what is in the entity mapper %4$s 3. Fetch from the database using %3$s',
-                                    'event_espresso'
-                                ),
-                                get_class($this),
-                                get_class($model) . '::instance()->add_to_entity_map()',
-                                get_class($model) . '::instance()->get_one_by_ID()',
-                                '<br />'
-                            )
-                        );
-                    }
-                    $results = $model->update_by_ID($save_cols_n_values, $this->ID());
-                } else {
-                    $results = $model->insert($save_cols_n_values);
-                    $this->_update_cached_related_model_objs_fks();
-                }
-            }
-        } else {// there is NO primary key
-            $already_in_db = false;
-            foreach ($model->unique_indexes() as $index) {
-                $uniqueness_where_params = array_intersect_key($save_cols_n_values, $index->fields());
-                if ($model->exists(array($uniqueness_where_params))) {
-                    $already_in_db = true;
-                }
-            }
-            if ($already_in_db) {
-                $combined_pk_fields_n_values = array_intersect_key(
-                    $save_cols_n_values,
-                    $model->get_combined_primary_key_fields()
-                );
-                $results = $model->update(
-                    $save_cols_n_values,
-                    $combined_pk_fields_n_values
-                );
-            } else {
-                $results = $model->insert($save_cols_n_values);
-            }
-        }
-        // restore the old assumption about values being prepared by the model object
-        $model->assume_values_already_prepared_by_model_object(
-            $old_assumption_concerning_value_preparation
-        );
-        /**
-         * After saving the model object this action is called
-         *
-         * @param EE_Base_Class $model_object which was just saved
-         * @param boolean|int   $results      if it were updated, TRUE or FALSE; if it were newly inserted
-         *                                    the new ID (or 0 if an error occurred and it wasn't updated)
-         */
-        do_action('AHEE__EE_Base_Class__save__end', $this, $results);
-        $this->_has_changes = false;
-        return $results;
-    }
-
-
-    /**
-     * Updates the foreign key on related models objects pointing to this to have this model object's ID
-     * as their foreign key.  If the cached related model objects already exist in the db, saves them (so that the DB
-     * is consistent) Especially useful in case we JUST added this model object ot the database and we want to let its
-     * cached relations with foreign keys to it know about that change. Eg: we've created a transaction but haven't
-     * saved it to the db. We also create a registration and don't save it to the DB, but we DO cache it on the
-     * transaction. Now, when we save the transaction, the registration's TXN_ID will be automatically updated, whether
-     * or not they exist in the DB (if they do, their DB records will be automatically updated)
-     *
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _update_cached_related_model_objs_fks()
-    {
-        $model = $this->get_model();
-        foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if ($relation_obj instanceof EE_Has_Many_Relation) {
-                foreach ($this->get_all_from_cache($relation_name) as $related_model_obj_in_cache) {
-                    $fk_to_this = $related_model_obj_in_cache->get_model()->get_foreign_key_to(
-                        $model->get_this_model_name()
-                    );
-                    $related_model_obj_in_cache->set($fk_to_this->get_name(), $this->ID());
-                    if ($related_model_obj_in_cache->ID()) {
-                        $related_model_obj_in_cache->save();
-                    }
-                }
-            }
-        }
-    }
-
-
-    /**
-     * Saves this model object and its NEW cached relations to the database.
-     * (Meaning, for now, IT DOES NOT WORK if the cached items already exist in the DB.
-     * In order for that to work, we would need to mark model objects as dirty/clean...
-     * because otherwise, there's a potential for infinite looping of saving
-     * Saves the cached related model objects, and ensures the relation between them
-     * and this object and properly setup
-     *
-     * @return int ID of new model object on save; 0 on failure+
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function save_new_cached_related_model_objs()
-    {
-        // make sure this has been saved
-        if (! $this->ID()) {
-            $id = $this->save();
-        } else {
-            $id = $this->ID();
-        }
-        // now save all the NEW cached model objects  (ie they don't exist in the DB)
-        foreach ($this->get_model()->relation_settings() as $relationName => $relationObj) {
-            if ($this->_model_relations[ $relationName ]) {
-                // is this a relation where we should expect just ONE related object (ie, EE_Belongs_To_relation)
-                // or MANY related objects (ie, EE_HABTM_Relation or EE_Has_Many_Relation)?
-                /* @var $related_model_obj EE_Base_Class */
-                if ($relationObj instanceof EE_Belongs_To_Relation) {
-                    // add a relation to that relation type (which saves the appropriate thing in the process)
-                    // but ONLY if it DOES NOT exist in the DB
-                    $related_model_obj = $this->_model_relations[ $relationName ];
-                    // if( ! $related_model_obj->ID()){
-                    $this->_add_relation_to($related_model_obj, $relationName);
-                    $related_model_obj->save_new_cached_related_model_objs();
-                    // }
-                } else {
-                    foreach ($this->_model_relations[ $relationName ] as $related_model_obj) {
-                        // add a relation to that relation type (which saves the appropriate thing in the process)
-                        // but ONLY if it DOES NOT exist in the DB
-                        // if( ! $related_model_obj->ID()){
-                        $this->_add_relation_to($related_model_obj, $relationName);
-                        $related_model_obj->save_new_cached_related_model_objs();
-                        // }
-                    }
-                }
-            }
-        }
-        return $id;
-    }
-
-
-    /**
-     * for getting a model while instantiated.
-     *
-     * @return EEM_Base | EEM_CPT_Base
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_model()
-    {
-        if (! $this->_model) {
-            $modelName = self::_get_model_classname(get_class($this));
-            $this->_model = self::_get_model_instance_with_name($modelName, $this->_timezone);
-        } else {
-            $this->_model->set_timezone($this->_timezone);
-        }
-        return $this->_model;
-    }
-
-
-    /**
-     * @param $props_n_values
-     * @param $classname
-     * @return mixed bool|EE_Base_Class|EEM_CPT_Base
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected static function _get_object_from_entity_mapper($props_n_values, $classname)
-    {
-        // TODO: will not work for Term_Relationships because they have no PK!
-        $primary_id_ref = self::_get_primary_key_name($classname);
-        if (array_key_exists($primary_id_ref, $props_n_values)
-            && ! empty($props_n_values[ $primary_id_ref ])
-        ) {
-            $id = $props_n_values[ $primary_id_ref ];
-            return self::_get_model($classname)->get_from_entity_map($id);
-        }
-        return false;
-    }
-
-
-    /**
-     * This is called by child static "new_instance" method and we'll check to see if there is an existing db entry for
-     * the primary key (if present in incoming values). If there is a key in the incoming array that matches the
-     * primary key for the model AND it is not null, then we check the db. If there's a an object we return it.  If not
-     * we return false.
-     *
-     * @param  array  $props_n_values   incoming array of properties and their values
-     * @param  string $classname        the classname of the child class
-     * @param null    $timezone
-     * @param array   $date_formats     incoming date_formats in an array where the first value is the
-     *                                  date_format and the second value is the time format
-     * @return mixed (EE_Base_Class|bool)
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws ReflectionException
-     * @throws ReflectionException
-     */
-    protected static function _check_for_object($props_n_values, $classname, $timezone = null, $date_formats = array())
-    {
-        $existing = null;
-        $model = self::_get_model($classname, $timezone);
-        if ($model->has_primary_key_field()) {
-            $primary_id_ref = self::_get_primary_key_name($classname);
-            if (array_key_exists($primary_id_ref, $props_n_values)
-                && ! empty($props_n_values[ $primary_id_ref ])
-            ) {
-                $existing = $model->get_one_by_ID(
-                    $props_n_values[ $primary_id_ref ]
-                );
-            }
-        } elseif ($model->has_all_combined_primary_key_fields($props_n_values)) {
-            // no primary key on this model, but there's still a matching item in the DB
-            $existing = self::_get_model($classname, $timezone)->get_one_by_ID(
-                self::_get_model($classname, $timezone)
-                    ->get_index_primary_key_string($props_n_values)
-            );
-        }
-        if ($existing) {
-            // set date formats if present before setting values
-            if (! empty($date_formats) && is_array($date_formats)) {
-                $existing->set_date_format($date_formats[0]);
-                $existing->set_time_format($date_formats[1]);
-            } else {
-                // set default formats for date and time
-                $existing->set_date_format(get_option('date_format'));
-                $existing->set_time_format(get_option('time_format'));
-            }
-            foreach ($props_n_values as $property => $field_value) {
-                $existing->set($property, $field_value);
-            }
-            return $existing;
-        }
-        return false;
-    }
-
-
-    /**
-     * Gets the EEM_*_Model for this class
-     *
-     * @access public now, as this is more convenient
-     * @param      $classname
-     * @param null $timezone
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return EEM_Base
-     */
-    protected static function _get_model($classname, $timezone = null)
-    {
-        // find model for this class
-        if (! $classname) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'What were you thinking calling _get_model(%s)?? You need to specify the class name',
-                        'event_espresso'
-                    ),
-                    $classname
-                )
-            );
-        }
-        $modelName = self::_get_model_classname($classname);
-        return self::_get_model_instance_with_name($modelName, $timezone);
-    }
-
-
-    /**
-     * Gets the model instance (eg instance of EEM_Attendee) given its classname (eg EE_Attendee)
-     *
-     * @param string $model_classname
-     * @param null   $timezone
-     * @return EEM_Base
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected static function _get_model_instance_with_name($model_classname, $timezone = null)
-    {
-        $model_classname = str_replace('EEM_', '', $model_classname);
-        $model = EE_Registry::instance()->load_model($model_classname);
-        $model->set_timezone($timezone);
-        return $model;
-    }
-
-
-    /**
-     * If a model name is provided (eg Registration), gets the model classname for that model.
-     * Also works if a model class's classname is provided (eg EE_Registration).
-     *
-     * @param null $model_name
-     * @return string like EEM_Attendee
-     */
-    private static function _get_model_classname($model_name = null)
-    {
-        if (strpos($model_name, 'EE_') === 0) {
-            $model_classname = str_replace('EE_', 'EEM_', $model_name);
-        } else {
-            $model_classname = 'EEM_' . $model_name;
-        }
-        return $model_classname;
-    }
-
-
-    /**
-     * returns the name of the primary key attribute
-     *
-     * @param null $classname
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return string
-     */
-    protected static function _get_primary_key_name($classname = null)
-    {
-        if (! $classname) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__('What were you thinking calling _get_primary_key_name(%s)', 'event_espresso'),
-                    $classname
-                )
-            );
-        }
-        return self::_get_model($classname)->get_primary_key_field()->get_name();
-    }
-
-
-    /**
-     * Gets the value of the primary key.
-     * If the object hasn't yet been saved, it should be whatever the model field's default was
-     * (eg, if this were the EE_Event class, look at the primary key field on EEM_Event and see what its default value
-     * is. Usually defaults for integer primary keys are 0; string primary keys are usually NULL).
-     *
-     * @return mixed, if the primary key is of type INT it'll be an int. Otherwise it could be a string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function ID()
-    {
-        $model = $this->get_model();
-        // now that we know the name of the variable, use a variable variable to get its value and return its
-        if ($model->has_primary_key_field()) {
-            return $this->_fields[ $model->primary_key_name() ];
-        }
-        return $model->get_index_primary_key_string($this->_fields);
-    }
-
-
-    /**
-     * Adds a relationship to the specified EE_Base_Class object, given the relationship's name. Eg, if the current
-     * model is related to a group of events, the $relationName should be 'Event', and should be a key in the EE
-     * Model's $_model_relations array. If this model object doesn't exist in the DB, just caches the related thing
-     *
-     * @param mixed  $otherObjectModelObjectOrID       EE_Base_Class or the ID of the other object
-     * @param string $relationName                     eg 'Events','Question',etc.
-     *                                                 an attendee to a group, you also want to specify which role they
-     *                                                 will have in that group. So you would use this parameter to
-     *                                                 specify array('role-column-name'=>'role-id')
-     * @param array  $extra_join_model_fields_n_values You can optionally include an array of key=>value pairs that
-     *                                                 allow you to further constrict the relation to being added.
-     *                                                 However, keep in mind that the columns (keys) given must match a
-     *                                                 column on the JOIN table and currently only the HABTM models
-     *                                                 accept these additional conditions.  Also remember that if an
-     *                                                 exact match isn't found for these extra cols/val pairs, then a
-     *                                                 NEW row is created in the join table.
-     * @param null   $cache_id
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @return EE_Base_Class the object the relation was added to
-     */
-    public function _add_relation_to(
-        $otherObjectModelObjectOrID,
-        $relationName,
-        $extra_join_model_fields_n_values = array(),
-        $cache_id = null
-    ) {
-        $model = $this->get_model();
-        // if this thing exists in the DB, save the relation to the DB
-        if ($this->ID()) {
-            $otherObject = $model->add_relationship_to(
-                $this,
-                $otherObjectModelObjectOrID,
-                $relationName,
-                $extra_join_model_fields_n_values
-            );
-            // clear cache so future get_many_related and get_first_related() return new results.
-            $this->clear_cache($relationName, $otherObject, true);
-            if ($otherObject instanceof EE_Base_Class) {
-                $otherObject->clear_cache($model->get_this_model_name(), $this);
-            }
-        } else {
-            // this thing doesn't exist in the DB,  so just cache it
-            if (! $otherObjectModelObjectOrID instanceof EE_Base_Class) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Before a model object is saved to the database, calls to _add_relation_to must be passed an actual object, not just an ID. You provided %s as the model object to a %s',
-                            'event_espresso'
-                        ),
-                        $otherObjectModelObjectOrID,
-                        get_class($this)
-                    )
-                );
-            }
-            $otherObject = $otherObjectModelObjectOrID;
-            $this->cache($relationName, $otherObjectModelObjectOrID, $cache_id);
-        }
-        if ($otherObject instanceof EE_Base_Class) {
-            // fix the reciprocal relation too
-            if ($otherObject->ID()) {
-                // its saved so assumed relations exist in the DB, so we can just
-                // clear the cache so future queries use the updated info in the DB
-                $otherObject->clear_cache(
-                    $model->get_this_model_name(),
-                    null,
-                    true
-                );
-            } else {
-                // it's not saved, so it caches relations like this
-                $otherObject->cache($model->get_this_model_name(), $this);
-            }
-        }
-        return $otherObject;
-    }
-
-
-    /**
-     * Removes a relationship to the specified EE_Base_Class object, given the relationships' name. Eg, if the current
-     * model is related to a group of events, the $relationName should be 'Events', and should be a key in the EE
-     * Model's $_model_relations array. If this model object doesn't exist in the DB, just removes the related thing
-     * from the cache
-     *
-     * @param mixed  $otherObjectModelObjectOrID
-     *                EE_Base_Class or the ID of the other object, OR an array key into the cache if this isn't saved
-     *                to the DB yet
-     * @param string $relationName
-     * @param array  $where_query
-     *                You can optionally include an array of key=>value pairs that allow you to further constrict the
-     *                relation to being added. However, keep in mind that the columns (keys) given must match a column
-     *                on the JOIN table and currently only the HABTM models accept these additional conditions. Also
-     *                remember that if an exact match isn't found for these extra cols/val pairs, then no row is
-     *                deleted.
-     * @return EE_Base_Class the relation was removed from
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function _remove_relation_to($otherObjectModelObjectOrID, $relationName, $where_query = array())
-    {
-        if ($this->ID()) {
-            // if this exists in the DB, save the relation change to the DB too
-            $otherObject = $this->get_model()->remove_relationship_to(
-                $this,
-                $otherObjectModelObjectOrID,
-                $relationName,
-                $where_query
-            );
-            $this->clear_cache(
-                $relationName,
-                $otherObject
-            );
-        } else {
-            // this doesn't exist in the DB, just remove it from the cache
-            $otherObject = $this->clear_cache(
-                $relationName,
-                $otherObjectModelObjectOrID
-            );
-        }
-        if ($otherObject instanceof EE_Base_Class) {
-            $otherObject->clear_cache(
-                $this->get_model()->get_this_model_name(),
-                $this
-            );
-        }
-        return $otherObject;
-    }
-
-
-    /**
-     * Removes ALL the related things for the $relationName.
-     *
-     * @param string $relationName
-     * @param array  $where_query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @return EE_Base_Class
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function _remove_relations($relationName, $where_query_params = array())
-    {
-        if ($this->ID()) {
-            // if this exists in the DB, save the relation change to the DB too
-            $otherObjects = $this->get_model()->remove_relations(
-                $this,
-                $relationName,
-                $where_query_params
-            );
-            $this->clear_cache(
-                $relationName,
-                null,
-                true
-            );
-        } else {
-            // this doesn't exist in the DB, just remove it from the cache
-            $otherObjects = $this->clear_cache(
-                $relationName,
-                null,
-                true
-            );
-        }
-        if (is_array($otherObjects)) {
-            foreach ($otherObjects as $otherObject) {
-                $otherObject->clear_cache(
-                    $this->get_model()->get_this_model_name(),
-                    $this
-                );
-            }
-        }
-        return $otherObjects;
-    }
-
-
-    /**
-     * Gets all the related model objects of the specified type. Eg, if the current class if
-     * EE_Event, you could call $this->get_many_related('Registration') to get an array of all the
-     * EE_Registration objects which related to this event. Note: by default, we remove the "default query params"
-     * because we want to get even deleted items etc.
-     *
-     * @param string $relationName key in the model's _model_relations array
-     * @param array  $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @return EE_Base_Class[]     Results not necessarily indexed by IDs, because some results might not have primary
-     *                             keys or might not be saved yet. Consider using EEM_Base::get_IDs() on these
-     *                             results if you want IDs
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_many_related($relationName, $query_params = array())
-    {
-        if ($this->ID()) {
-            // this exists in the DB, so get the related things from either the cache or the DB
-            // if there are query parameters, forget about caching the related model objects.
-            if ($query_params) {
-                $related_model_objects = $this->get_model()->get_all_related(
-                    $this,
-                    $relationName,
-                    $query_params
-                );
-            } else {
-                // did we already cache the result of this query?
-                $cached_results = $this->get_all_from_cache($relationName);
-                if (! $cached_results) {
-                    $related_model_objects = $this->get_model()->get_all_related(
-                        $this,
-                        $relationName,
-                        $query_params
-                    );
-                    // if no query parameters were passed, then we got all the related model objects
-                    // for that relation. We can cache them then.
-                    foreach ($related_model_objects as $related_model_object) {
-                        $this->cache($relationName, $related_model_object);
-                    }
-                } else {
-                    $related_model_objects = $cached_results;
-                }
-            }
-        } else {
-            // this doesn't exist in the DB, so just get the related things from the cache
-            $related_model_objects = $this->get_all_from_cache($relationName);
-        }
-        return $related_model_objects;
-    }
-
-
-    /**
-     * Instead of getting the related model objects, simply counts them. Ignores default_where_conditions by default,
-     * unless otherwise specified in the $query_params
-     *
-     * @param string $relation_name  model_name like 'Event', or 'Registration'
-     * @param array  $query_params   @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_count name of field to count by. By default, uses primary key
-     * @param bool   $distinct       if we want to only count the distinct values for the column then you can trigger
-     *                               that by the setting $distinct to TRUE;
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function count_related($relation_name, $query_params = array(), $field_to_count = null, $distinct = false)
-    {
-        return $this->get_model()->count_related(
-            $this,
-            $relation_name,
-            $query_params,
-            $field_to_count,
-            $distinct
-        );
-    }
-
-
-    /**
-     * Instead of getting the related model objects, simply sums up the values of the specified field.
-     * Note: ignores default_where_conditions by default, unless otherwise specified in the $query_params
-     *
-     * @param string $relation_name model_name like 'Event', or 'Registration'
-     * @param array  $query_params  @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_sum  name of field to count by.
-     *                              By default, uses primary key
-     *                              (which doesn't make much sense, so you should probably change it)
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function sum_related($relation_name, $query_params = array(), $field_to_sum = null)
-    {
-        return $this->get_model()->sum_related(
-            $this,
-            $relation_name,
-            $query_params,
-            $field_to_sum
-        );
-    }
-
-
-    /**
-     * Gets the first (ie, one) related model object of the specified type.
-     *
-     * @param string $relationName key in the model's _model_relations array
-     * @param array  $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Base_Class (not an array, a single object)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_first_related($relationName, $query_params = array())
-    {
-        $model = $this->get_model();
-        if ($this->ID()) {// this exists in the DB, get from the cache OR the DB
-            // if they've provided some query parameters, don't bother trying to cache the result
-            // also make sure we're not caching the result of get_first_related
-            // on a relation which should have an array of objects (because the cache might have an array of objects)
-            if ($query_params
-                || ! $model->related_settings_for($relationName)
-                     instanceof
-                     EE_Belongs_To_Relation
-            ) {
-                $related_model_object = $model->get_first_related(
-                    $this,
-                    $relationName,
-                    $query_params
-                );
-            } else {
-                // first, check if we've already cached the result of this query
-                $cached_result = $this->get_one_from_cache($relationName);
-                if (! $cached_result) {
-                    $related_model_object = $model->get_first_related(
-                        $this,
-                        $relationName,
-                        $query_params
-                    );
-                    $this->cache($relationName, $related_model_object);
-                } else {
-                    $related_model_object = $cached_result;
-                }
-            }
-        } else {
-            $related_model_object = null;
-            // this doesn't exist in the Db,
-            // but maybe the relation is of type belongs to, and so the related thing might
-            if ($model->related_settings_for($relationName) instanceof EE_Belongs_To_Relation) {
-                $related_model_object = $model->get_first_related(
-                    $this,
-                    $relationName,
-                    $query_params
-                );
-            }
-            // this doesn't exist in the DB and apparently the thing it belongs to doesn't either,
-            // just get what's cached on this object
-            if (! $related_model_object) {
-                $related_model_object = $this->get_one_from_cache($relationName);
-            }
-        }
-        return $related_model_object;
-    }
-
-
-    /**
-     * Does a delete on all related objects of type $relationName and removes
-     * the current model object's relation to them. If they can't be deleted (because
-     * of blocking related model objects) does nothing. If the related model objects are
-     * soft-deletable, they will be soft-deleted regardless of related blocking model objects.
-     * If this model object doesn't exist yet in the DB, just removes its related things
-     *
-     * @param string $relationName
-     * @param array  $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return int how many deleted
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function delete_related($relationName, $query_params = array())
-    {
-        if ($this->ID()) {
-            $count = $this->get_model()->delete_related(
-                $this,
-                $relationName,
-                $query_params
-            );
-        } else {
-            $count = count($this->get_all_from_cache($relationName));
-            $this->clear_cache($relationName, null, true);
-        }
-        return $count;
-    }
-
-
-    /**
-     * Does a hard delete (ie, removes the DB row) on all related objects of type $relationName and removes
-     * the current model object's relation to them. If they can't be deleted (because
-     * of blocking related model objects) just does a soft delete on it instead, if possible.
-     * If the related thing isn't a soft-deletable model object, this function is identical
-     * to delete_related(). If this model object doesn't exist in the DB, just remove its related things
-     *
-     * @param string $relationName
-     * @param array  $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return int how many deleted (including those soft deleted)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function delete_related_permanently($relationName, $query_params = array())
-    {
-        if ($this->ID()) {
-            $count = $this->get_model()->delete_related_permanently(
-                $this,
-                $relationName,
-                $query_params
-            );
-        } else {
-            $count = count($this->get_all_from_cache($relationName));
-        }
-        $this->clear_cache($relationName, null, true);
-        return $count;
-    }
-
-
-    /**
-     * is_set
-     * Just a simple utility function children can use for checking if property exists
-     *
-     * @access  public
-     * @param  string $field_name property to check
-     * @return bool                              TRUE if existing,FALSE if not.
-     */
-    public function is_set($field_name)
-    {
-        return isset($this->_fields[ $field_name ]);
-    }
-
-
-    /**
-     * Just a simple utility function children can use for checking if property (or properties) exists and throwing an
-     * EE_Error exception if they don't
-     *
-     * @param  mixed (string|array) $properties properties to check
-     * @throws EE_Error
-     * @return bool                              TRUE if existing, throw EE_Error if not.
-     */
-    protected function _property_exists($properties)
-    {
-        foreach ((array) $properties as $property_name) {
-            // first make sure this property exists
-            if (! $this->_fields[ $property_name ]) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Trying to retrieve a non-existent property (%s).  Double check the spelling please',
-                            'event_espresso'
-                        ),
-                        $property_name
-                    )
-                );
-            }
-        }
-        return true;
-    }
-
-
-    /**
-     * This simply returns an array of model fields for this object
-     *
-     * @return array
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function model_field_array()
-    {
-        $fields = $this->get_model()->field_settings(false);
-        $properties = array();
-        // remove prepended underscore
-        foreach ($fields as $field_name => $settings) {
-            $properties[ $field_name ] = $this->get($field_name);
-        }
-        return $properties;
-    }
-
-
-    /**
-     * Very handy general function to allow for plugins to extend any child of EE_Base_Class.
-     * If a method is called on a child of EE_Base_Class that doesn't exist, this function is called
-     * (http://www.garfieldtech.com/blog/php-magic-call) and passed the method's name and arguments.
-     * Instead of requiring a plugin to extend the EE_Base_Class
-     * (which works fine is there's only 1 plugin, but when will that happen?)
-     * they can add a hook onto 'filters_hook_espresso__{className}__{methodName}'
-     * (eg, filters_hook_espresso__EE_Answer__my_great_function)
-     * and accepts 2 arguments: the object on which the function was called,
-     * and an array of the original arguments passed to the function.
-     * Whatever their callback function returns will be returned by this function.
-     * Example: in functions.php (or in a plugin):
-     *      add_filter('FHEE__EE_Answer__my_callback','my_callback',10,3);
-     *      function my_callback($previousReturnValue,EE_Base_Class $object,$argsArray){
-     *          $returnString= "you called my_callback! and passed args:".implode(",",$argsArray);
-     *          return $previousReturnValue.$returnString;
-     *      }
-     * require('EE_Answer.class.php');
-     * $answer= EE_Answer::new_instance(array('REG_ID' => 2,'QST_ID' => 3,'ANS_value' => The answer is 42'));
-     * echo $answer->my_callback('monkeys',100);
-     * //will output "you called my_callback! and passed args:monkeys,100"
-     *
-     * @param string $methodName name of method which was called on a child of EE_Base_Class, but which
-     * @param array  $args       array of original arguments passed to the function
-     * @throws EE_Error
-     * @return mixed whatever the plugin which calls add_filter decides
-     */
-    public function __call($methodName, $args)
-    {
-        $className = get_class($this);
-        $tagName = "FHEE__{$className}__{$methodName}";
-        if (! has_filter($tagName)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "Method %s on class %s does not exist! You can create one with the following code in functions.php or in a plugin: add_filter('%s','my_callback',10,3);function my_callback(\$previousReturnValue,EE_Base_Class \$object, \$argsArray){/*function body*/return \$whatever;}",
-                        'event_espresso'
-                    ),
-                    $methodName,
-                    $className,
-                    $tagName
-                )
-            );
-        }
-        return apply_filters($tagName, null, $this, $args);
-    }
-
-
-    /**
-     * Similar to insert_post_meta, adds a record in the Extra_Meta model's table with the given key and value.
-     * A $previous_value can be specified in case there are many meta rows with the same key
-     *
-     * @param string $meta_key
-     * @param mixed  $meta_value
-     * @param mixed  $previous_value
-     * @return bool|int # of records updated (or BOOLEAN if we actually ended up inserting the extra meta row)
-     *                  NOTE: if the values haven't changed, returns 0
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function update_extra_meta($meta_key, $meta_value, $previous_value = null)
-    {
-        $query_params = array(
-            array(
-                'EXM_key'  => $meta_key,
-                'OBJ_ID'   => $this->ID(),
-                'EXM_type' => $this->get_model()->get_this_model_name(),
-            ),
-        );
-        if ($previous_value !== null) {
-            $query_params[0]['EXM_value'] = $meta_value;
-        }
-        $existing_rows_like_that = EEM_Extra_Meta::instance()->get_all($query_params);
-        if (! $existing_rows_like_that) {
-            return $this->add_extra_meta($meta_key, $meta_value);
-        }
-        foreach ($existing_rows_like_that as $existing_row) {
-            $existing_row->save(array('EXM_value' => $meta_value));
-        }
-        return count($existing_rows_like_that);
-    }
-
-
-    /**
-     * Adds a new extra meta record. If $unique is set to TRUE, we'll first double-check
-     * no other extra meta for this model object have the same key. Returns TRUE if the
-     * extra meta row was entered, false if not
-     *
-     * @param string  $meta_key
-     * @param mixed   $meta_value
-     * @param boolean $unique
-     * @return boolean
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws ReflectionException
-     */
-    public function add_extra_meta($meta_key, $meta_value, $unique = false)
-    {
-        if ($unique) {
-            $existing_extra_meta = EEM_Extra_Meta::instance()->get_one(
-                array(
-                    array(
-                        'EXM_key'  => $meta_key,
-                        'OBJ_ID'   => $this->ID(),
-                        'EXM_type' => $this->get_model()->get_this_model_name(),
-                    ),
-                )
-            );
-            if ($existing_extra_meta) {
-                return false;
-            }
-        }
-        $new_extra_meta = EE_Extra_Meta::new_instance(
-            array(
-                'EXM_key'   => $meta_key,
-                'EXM_value' => $meta_value,
-                'OBJ_ID'    => $this->ID(),
-                'EXM_type'  => $this->get_model()->get_this_model_name(),
-            )
-        );
-        $new_extra_meta->save();
-        return true;
-    }
-
-
-    /**
-     * Deletes all the extra meta rows for this record as specified by key. If $meta_value
-     * is specified, only deletes extra meta records with that value.
-     *
-     * @param string $meta_key
-     * @param mixed  $meta_value
-     * @return int number of extra meta rows deleted
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function delete_extra_meta($meta_key, $meta_value = null)
-    {
-        $query_params = array(
-            array(
-                'EXM_key'  => $meta_key,
-                'OBJ_ID'   => $this->ID(),
-                'EXM_type' => $this->get_model()->get_this_model_name(),
-            ),
-        );
-        if ($meta_value !== null) {
-            $query_params[0]['EXM_value'] = $meta_value;
-        }
-        return EEM_Extra_Meta::instance()->delete($query_params);
-    }
-
-
-    /**
-     * Gets the extra meta with the given meta key. If you specify "single" we just return 1, otherwise
-     * an array of everything found. Requires that this model actually have a relation of type EE_Has_Many_Any_Relation.
-     * You can specify $default is case you haven't found the extra meta
-     *
-     * @param string  $meta_key
-     * @param boolean $single
-     * @param mixed   $default if we don't find anything, what should we return?
-     * @return mixed single value if $single; array if ! $single
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_extra_meta($meta_key, $single = false, $default = null)
-    {
-        if ($single) {
-            $result = $this->get_first_related(
-                'Extra_Meta',
-                array(array('EXM_key' => $meta_key))
-            );
-            if ($result instanceof EE_Extra_Meta) {
-                return $result->value();
-            }
-        } else {
-            $results = $this->get_many_related(
-                'Extra_Meta',
-                array(array('EXM_key' => $meta_key))
-            );
-            if ($results) {
-                $values = array();
-                foreach ($results as $result) {
-                    if ($result instanceof EE_Extra_Meta) {
-                        $values[ $result->ID() ] = $result->value();
-                    }
-                }
-                return $values;
-            }
-        }
-        // if nothing discovered yet return default.
-        return apply_filters(
-            'FHEE__EE_Base_Class__get_extra_meta__default_value',
-            $default,
-            $meta_key,
-            $single,
-            $this
-        );
-    }
-
-
-    /**
-     * Returns a simple array of all the extra meta associated with this model object.
-     * If $one_of_each_key is true (Default), it will be an array of simple key-value pairs, keys being the
-     * extra meta's key, and teh value being its value. However, if there are duplicate extra meta rows with
-     * the same key, only one will be used. (eg array('foo'=>'bar','monkey'=>123))
-     * If $one_of_each_key is false, it will return an array with the top-level keys being
-     * the extra meta keys, but their values are also arrays, which have the extra-meta's ID as their sub-key, and
-     * finally the extra meta's value as each sub-value. (eg
-     * array('foo'=>array(1=>'bar',2=>'bill'),'monkey'=>array(3=>123)))
-     *
-     * @param boolean $one_of_each_key
-     * @return array
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function all_extra_meta_array($one_of_each_key = true)
-    {
-        $return_array = array();
-        if ($one_of_each_key) {
-            $extra_meta_objs = $this->get_many_related(
-                'Extra_Meta',
-                array('group_by' => 'EXM_key')
-            );
-            foreach ($extra_meta_objs as $extra_meta_obj) {
-                if ($extra_meta_obj instanceof EE_Extra_Meta) {
-                    $return_array[ $extra_meta_obj->key() ] = $extra_meta_obj->value();
-                }
-            }
-        } else {
-            $extra_meta_objs = $this->get_many_related('Extra_Meta');
-            foreach ($extra_meta_objs as $extra_meta_obj) {
-                if ($extra_meta_obj instanceof EE_Extra_Meta) {
-                    if (! isset($return_array[ $extra_meta_obj->key() ])) {
-                        $return_array[ $extra_meta_obj->key() ] = array();
-                    }
-                    $return_array[ $extra_meta_obj->key() ][ $extra_meta_obj->ID() ] = $extra_meta_obj->value();
-                }
-            }
-        }
-        return $return_array;
-    }
-
-
-    /**
-     * Gets a pretty nice displayable nice for this model object. Often overridden
-     *
-     * @return string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function name()
-    {
-        // find a field that's not a text field
-        $field_we_can_use = $this->get_model()->get_a_field_of_type('EE_Text_Field_Base');
-        if ($field_we_can_use) {
-            return $this->get($field_we_can_use->get_name());
-        }
-        $first_few_properties = $this->model_field_array();
-        $first_few_properties = array_slice($first_few_properties, 0, 3);
-        $name_parts = array();
-        foreach ($first_few_properties as $name => $value) {
-            $name_parts[] = "$name:$value";
-        }
-        return implode(',', $name_parts);
-    }
-
-
-    /**
-     * in_entity_map
-     * Checks if this model object has been proven to already be in the entity map
-     *
-     * @return boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function in_entity_map()
-    {
-        // well, if we looked, did we find it in the entity map?
-        return $this->ID() && $this->get_model()->get_from_entity_map($this->ID()) === $this;
-    }
-
-
-    /**
-     * refresh_from_db
-     * Makes sure the fields and values on this model object are in-sync with what's in the database.
-     *
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error if this model object isn't in the entity mapper (because then you should
-     * just use what's in the entity mapper and refresh it) and WP_DEBUG is TRUE
-     */
-    public function refresh_from_db()
-    {
-        if ($this->ID() && $this->in_entity_map()) {
-            $this->get_model()->refresh_entity_map_from_db($this->ID());
-        } else {
-            // if it doesn't have ID, you shouldn't be asking to refresh it from teh database (because its not in the database)
-            // if it has an ID but it's not in the map, and you're asking me to refresh it
-            // that's kinda dangerous. You should just use what's in the entity map, or add this to the entity map if there's
-            // absolutely nothing in it for this ID
-            if (WP_DEBUG) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Trying to refresh a model object with ID "%1$s" that\'s not in the entity map? First off: you should put it in the entity map by calling %2$s. Second off, if you want what\'s in the database right now, you should just call %3$s yourself and discard this model object.',
-                            'event_espresso'
-                        ),
-                        $this->ID(),
-                        get_class($this->get_model()) . '::instance()->add_to_entity_map()',
-                        get_class($this->get_model()) . '::instance()->refresh_entity_map()'
-                    )
-                );
-            }
-        }
-    }
-
-
-    /**
-     * Change $fields' values to $new_value_sql (which is a string of raw SQL)
-     *
-     * @since $VID:$
-     * @param EE_Model_Field_Base[] $fields
-     * @param string $new_value_sql
-     *      example: 'column_name=123',
-     *      or 'column_name=column_name+1',
-     *      or 'column_name= CASE
-     *          WHEN (`column_name` + `other_column` + 5) <= `yet_another_column`
-     *          THEN `column_name` + 5
-     *          ELSE `column_name`
-     *      END'
-     *      Also updates $field on this model object with the latest value from the database.
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function updateFieldsInDB($fields, $new_value_sql)
-    {
-        // First make sure this model object actually exists in the DB. It would be silly to try to update it in the DB
-        // if it wasn't even there to start off.
-        if (! $this->ID()) {
-            $this->save();
-        }
-        global $wpdb;
-        if (empty($fields)) {
-            throw new InvalidArgumentException(
-                esc_html__(
-                    'EE_Base_Class::updateFieldsInDB was passed an empty array of fields.',
-                    'event_espresso'
-                )
-            );
-        }
-        $first_field = reset($fields);
-        $table_alias = $first_field->get_table_alias();
-        foreach ($fields as $field) {
-            if ($table_alias !== $field->get_table_alias()) {
-                throw new InvalidArgumentException(
-                    sprintf(
-                        esc_html__(
-                            // @codingStandardsIgnoreStart
-                            'EE_Base_Class::updateFieldsInDB was passed fields for different tables ("%1$s" and "%2$s"), which is not supported. Instead, please call the method multiple times.',
-                            // @codingStandardsIgnoreEnd
-                            'event_espresso'
-                        ),
-                        $table_alias,
-                        $field->get_table_alias()
-                    )
-                );
-            }
-        }
-        // Ok the fields are now known to all be for the same table. Proceed with creating the SQL to update it.
-        $table_obj = $this->get_model()->get_table_obj_by_alias($table_alias);
-        $table_pk_value = $this->ID();
-        $table_name = $table_obj->get_table_name();
-        if ($table_obj instanceof EE_Secondary_Table) {
-            $table_pk_field_name = $table_obj->get_fk_on_table();
-        } else {
-            $table_pk_field_name = $table_obj->get_pk_column();
-        }
-
-        $query =
-            "UPDATE `{$table_name}`
+	/**
+	 * This is an array of the original properties and values provided during construction
+	 * of this model object. (keys are model field names, values are their values).
+	 * This list is important to remember so that when we are merging data from the db, we know
+	 * which values to override and which to not override.
+	 *
+	 * @var array
+	 */
+	protected $_props_n_values_provided_in_constructor;
+
+	/**
+	 * Timezone
+	 * This gets set by the "set_timezone()" method so that we know what timezone incoming strings|timestamps are in.
+	 * This can also be used before a get to set what timezone you want strings coming out of the object to be in.  NOT
+	 * all EE_Base_Class child classes use this property but any that use a EE_Datetime_Field data type will have
+	 * access to it.
+	 *
+	 * @var string
+	 */
+	protected $_timezone;
+
+	/**
+	 * date format
+	 * pattern or format for displaying dates
+	 *
+	 * @var string $_dt_frmt
+	 */
+	protected $_dt_frmt;
+
+	/**
+	 * time format
+	 * pattern or format for displaying time
+	 *
+	 * @var string $_tm_frmt
+	 */
+	protected $_tm_frmt;
+
+	/**
+	 * This property is for holding a cached array of object properties indexed by property name as the key.
+	 * The purpose of this is for setting a cache on properties that may have calculated values after a
+	 * prepare_for_get.  That way the cache can be checked first and the calculated property returned instead of having
+	 * to recalculate. Used by _set_cached_property() and _get_cached_property() methods.
+	 *
+	 * @var array
+	 */
+	protected $_cached_properties = array();
+
+	/**
+	 * An array containing keys of the related model, and values are either an array of related mode objects or a
+	 * single
+	 * related model object. see the model's _model_relations. The keys should match those specified. And if the
+	 * relation is of type EE_Belongs_To (or one of its children), then there should only be ONE related model object,
+	 * all others have an array)
+	 *
+	 * @var array
+	 */
+	protected $_model_relations = array();
+
+	/**
+	 * Array where keys are field names (see the model's _fields property) and values are their values. To see what
+	 * their types should be, look at what that field object returns on its prepare_for_get and prepare_for_set methods)
+	 *
+	 * @var array
+	 */
+	protected $_fields = array();
+
+	/**
+	 * @var boolean indicating whether or not this model object is intended to ever be saved
+	 * For example, we might create model objects intended to only be used for the duration
+	 * of this request and to be thrown away, and if they were accidentally saved
+	 * it would be a bug.
+	 */
+	protected $_allow_persist = true;
+
+	/**
+	 * @var boolean indicating whether or not this model object's properties have changed since construction
+	 */
+	protected $_has_changes = false;
+
+	/**
+	 * @var EEM_Base
+	 */
+	protected $_model;
+
+	/**
+	 * This is a cache of results from custom selections done on a query that constructs this entity. The only purpose
+	 * for these values is for retrieval of the results, they are not further queryable and they are not persisted to
+	 * the db.  They also do not automatically update if there are any changes to the data that produced their results.
+	 * The format is a simple array of field_alias => field_value.  So for instance if a custom select was something
+	 * like,  "Select COUNT(Registration.REG_ID) as Registration_Count ...", then the resulting value will be in this
+	 * array as:
+	 * array(
+	 *  'Registration_Count' => 24
+	 * );
+	 * Note: if the custom select configuration for the query included a data type, the value will be in the data type
+	 * provided for the query (@see EventEspresso\core\domain\values\model\CustomSelects::__construct phpdocs for more
+	 * info)
+	 *
+	 * @var array
+	 */
+	protected $custom_selection_results = array();
+
+
+	/**
+	 * basic constructor for Event Espresso classes, performs any necessary initialization, and verifies it's children
+	 * play nice
+	 *
+	 * @param array   $fieldValues                             where each key is a field (ie, array key in the 2nd
+	 *                                                         layer of the model's _fields array, (eg, EVT_ID,
+	 *                                                         TXN_amount, QST_name, etc) and values are their values
+	 * @param boolean $bydb                                    a flag for setting if the class is instantiated by the
+	 *                                                         corresponding db model or not.
+	 * @param string  $timezone                                indicate what timezone you want any datetime fields to
+	 *                                                         be in when instantiating a EE_Base_Class object.
+	 * @param array   $date_formats                            An array of date formats to set on construct where first
+	 *                                                         value is the date_format and second value is the time
+	 *                                                         format.
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function __construct($fieldValues = array(), $bydb = false, $timezone = '', $date_formats = array())
+	{
+		$className = get_class($this);
+		do_action("AHEE__{$className}__construct", $this, $fieldValues);
+		$model = $this->get_model();
+		$model_fields = $model->field_settings(false);
+		// ensure $fieldValues is an array
+		$fieldValues = is_array($fieldValues) ? $fieldValues : array($fieldValues);
+		// verify client code has not passed any invalid field names
+		foreach ($fieldValues as $field_name => $field_value) {
+			if (! isset($model_fields[ $field_name ])) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Invalid field (%s) passed to constructor of %s. Allowed fields are :%s',
+							'event_espresso'
+						),
+						$field_name,
+						get_class($this),
+						implode(', ', array_keys($model_fields))
+					)
+				);
+			}
+		}
+		$this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
+		if (! empty($date_formats) && is_array($date_formats)) {
+			list($this->_dt_frmt, $this->_tm_frmt) = $date_formats;
+		} else {
+			// set default formats for date and time
+			$this->_dt_frmt = (string) get_option('date_format', 'Y-m-d');
+			$this->_tm_frmt = (string) get_option('time_format', 'g:i a');
+		}
+		// if db model is instantiating
+		if ($bydb) {
+			// client code has indicated these field values are from the database
+			foreach ($model_fields as $fieldName => $field) {
+				$this->set_from_db(
+					$fieldName,
+					isset($fieldValues[ $fieldName ]) ? $fieldValues[ $fieldName ] : null
+				);
+			}
+		} else {
+			// we're constructing a brand
+			// new instance of the model object. Generally, this means we'll need to do more field validation
+			foreach ($model_fields as $fieldName => $field) {
+				$this->set(
+					$fieldName,
+					isset($fieldValues[ $fieldName ]) ? $fieldValues[ $fieldName ] : null,
+					true
+				);
+			}
+		}
+		// remember what values were passed to this constructor
+		$this->_props_n_values_provided_in_constructor = $fieldValues;
+		// remember in entity mapper
+		if (! $bydb && $model->has_primary_key_field() && $this->ID()) {
+			$model->add_to_entity_map($this);
+		}
+		// setup all the relations
+		foreach ($model->relation_settings() as $relation_name => $relation_obj) {
+			if ($relation_obj instanceof EE_Belongs_To_Relation) {
+				$this->_model_relations[ $relation_name ] = null;
+			} else {
+				$this->_model_relations[ $relation_name ] = array();
+			}
+		}
+		/**
+		 * Action done at the end of each model object construction
+		 *
+		 * @param EE_Base_Class $this the model object just created
+		 */
+		do_action('AHEE__EE_Base_Class__construct__finished', $this);
+	}
+
+
+	/**
+	 * Gets whether or not this model object is allowed to persist/be saved to the database.
+	 *
+	 * @return boolean
+	 */
+	public function allow_persist()
+	{
+		return $this->_allow_persist;
+	}
+
+
+	/**
+	 * Sets whether or not this model object should be allowed to be saved to the DB.
+	 * Normally once this is set to FALSE you wouldn't set it back to TRUE, unless
+	 * you got new information that somehow made you change your mind.
+	 *
+	 * @param boolean $allow_persist
+	 * @return boolean
+	 */
+	public function set_allow_persist($allow_persist)
+	{
+		return $this->_allow_persist = $allow_persist;
+	}
+
+
+	/**
+	 * Gets the field's original value when this object was constructed during this request.
+	 * This can be helpful when determining if a model object has changed or not
+	 *
+	 * @param string $field_name
+	 * @return mixed|null
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_original($field_name)
+	{
+		if (isset($this->_props_n_values_provided_in_constructor[ $field_name ])
+			&& $field_settings = $this->get_model()->field_settings_for($field_name)
+		) {
+			return $field_settings->prepare_for_get($this->_props_n_values_provided_in_constructor[ $field_name ]);
+		}
+		return null;
+	}
+
+
+	/**
+	 * @param EE_Base_Class $obj
+	 * @return string
+	 */
+	public function get_class($obj)
+	{
+		return get_class($obj);
+	}
+
+
+	/**
+	 * Overrides parent because parent expects old models.
+	 * This also doesn't do any validation, and won't work for serialized arrays
+	 *
+	 * @param    string $field_name
+	 * @param    mixed  $field_value
+	 * @param bool      $use_default
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 */
+	public function set($field_name, $field_value, $use_default = false)
+	{
+		// if not using default and nothing has changed, and object has already been setup (has ID),
+		// then don't do anything
+		if (! $use_default
+			&& $this->_fields[ $field_name ] === $field_value
+			&& $this->ID()
+		) {
+			return;
+		}
+		$model = $this->get_model();
+		$this->_has_changes = true;
+		$field_obj = $model->field_settings_for($field_name);
+		if ($field_obj instanceof EE_Model_Field_Base) {
+			// if ( method_exists( $field_obj, 'set_timezone' )) {
+			if ($field_obj instanceof EE_Datetime_Field) {
+				$field_obj->set_timezone($this->_timezone);
+				$field_obj->set_date_format($this->_dt_frmt);
+				$field_obj->set_time_format($this->_tm_frmt);
+			}
+			$holder_of_value = $field_obj->prepare_for_set($field_value);
+			// should the value be null?
+			if (($field_value === null || $holder_of_value === null || $holder_of_value === '') && $use_default) {
+				$this->_fields[ $field_name ] = $field_obj->get_default_value();
+				/**
+				 * To save having to refactor all the models, if a default value is used for a
+				 * EE_Datetime_Field, and that value is not null nor is it a DateTime
+				 * object.  Then let's do a set again to ensure that it becomes a DateTime
+				 * object.
+				 *
+				 * @since 4.6.10+
+				 */
+				if ($field_obj instanceof EE_Datetime_Field
+					&& $this->_fields[ $field_name ] !== null
+					&& ! $this->_fields[ $field_name ] instanceof DateTime
+				) {
+					empty($this->_fields[ $field_name ])
+						? $this->set($field_name, time())
+						: $this->set($field_name, $this->_fields[ $field_name ]);
+				}
+			} else {
+				$this->_fields[ $field_name ] = $holder_of_value;
+			}
+			// if we're not in the constructor...
+			// now check if what we set was a primary key
+			if (// note: props_n_values_provided_in_constructor is only set at the END of the constructor
+				$this->_props_n_values_provided_in_constructor
+				&& $field_value
+				&& $field_name === $model->primary_key_name()
+			) {
+				// if so, we want all this object's fields to be filled either with
+				// what we've explicitly set on this model
+				// or what we have in the db
+				// echo "setting primary key!";
+				$fields_on_model = self::_get_model(get_class($this))->field_settings();
+				$obj_in_db = self::_get_model(get_class($this))->get_one_by_ID($field_value);
+				foreach ($fields_on_model as $field_obj) {
+					if (! array_key_exists($field_obj->get_name(), $this->_props_n_values_provided_in_constructor)
+						&& $field_obj->get_name() !== $field_name
+					) {
+						$this->set($field_obj->get_name(), $obj_in_db->get($field_obj->get_name()));
+					}
+				}
+				// oh this model object has an ID? well make sure its in the entity mapper
+				$model->add_to_entity_map($this);
+			}
+			// let's unset any cache for this field_name from the $_cached_properties property.
+			$this->_clear_cached_property($field_name);
+		} else {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'A valid EE_Model_Field_Base could not be found for the given field name: %s',
+						'event_espresso'
+					),
+					$field_name
+				)
+			);
+		}
+	}
+
+
+	/**
+	 * Set custom select values for model.
+	 *
+	 * @param array $custom_select_values
+	 */
+	public function setCustomSelectsValues(array $custom_select_values)
+	{
+		$this->custom_selection_results = $custom_select_values;
+	}
+
+
+	/**
+	 * Returns the custom select value for the provided alias if its set.
+	 * If not set, returns null.
+	 *
+	 * @param string $alias
+	 * @return string|int|float|null
+	 */
+	public function getCustomSelect($alias)
+	{
+		return isset($this->custom_selection_results[ $alias ])
+			? $this->custom_selection_results[ $alias ]
+			: null;
+	}
+
+
+	/**
+	 * This sets the field value on the db column if it exists for the given $column_name or
+	 * saves it to EE_Extra_Meta if the given $column_name does not match a db column.
+	 *
+	 * @see EE_message::get_column_value for related documentation on the necessity of this method.
+	 * @param string $field_name  Must be the exact column name.
+	 * @param mixed  $field_value The value to set.
+	 * @return int|bool @see EE_Base_Class::update_extra_meta() for return docs.
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_field_or_extra_meta($field_name, $field_value)
+	{
+		if ($this->get_model()->has_field($field_name)) {
+			$this->set($field_name, $field_value);
+			return true;
+		}
+		// ensure this object is saved first so that extra meta can be properly related.
+		$this->save();
+		return $this->update_extra_meta($field_name, $field_value);
+	}
+
+
+	/**
+	 * This retrieves the value of the db column set on this class or if that's not present
+	 * it will attempt to retrieve from extra_meta if found.
+	 * Example Usage:
+	 * Via EE_Message child class:
+	 * Due to the dynamic nature of the EE_messages system, EE_messengers will always have a "to",
+	 * "from", "subject", and "content" field (as represented in the EE_Message schema), however they may
+	 * also have additional main fields specific to the messenger.  The system accommodates those extra
+	 * fields through the EE_Extra_Meta table.  This method allows for EE_messengers to retrieve the
+	 * value for those extra fields dynamically via the EE_message object.
+	 *
+	 * @param  string $field_name expecting the fully qualified field name.
+	 * @return mixed|null  value for the field if found.  null if not found.
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_field_or_extra_meta($field_name)
+	{
+		if ($this->get_model()->has_field($field_name)) {
+			$column_value = $this->get($field_name);
+		} else {
+			// This isn't a column in the main table, let's see if it is in the extra meta.
+			$column_value = $this->get_extra_meta($field_name, true, null);
+		}
+		return $column_value;
+	}
+
+
+	/**
+	 * See $_timezone property for description of what the timezone property is for.  This SETS the timezone internally
+	 * for being able to reference what timezone we are running conversions on when converting TO the internal timezone
+	 * (UTC Unix Timestamp) for the object OR when converting FROM the internal timezone (UTC Unix Timestamp). This is
+	 * available to all child classes that may be using the EE_Datetime_Field for a field data type.
+	 *
+	 * @access public
+	 * @param string $timezone A valid timezone string as described by @link http://www.php.net/manual/en/timezones.php
+	 * @return void
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_timezone($timezone = '')
+	{
+		$this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
+		// make sure we clear all cached properties because they won't be relevant now
+		$this->_clear_cached_properties();
+		// make sure we update field settings and the date for all EE_Datetime_Fields
+		$model_fields = $this->get_model()->field_settings(false);
+		foreach ($model_fields as $field_name => $field_obj) {
+			if ($field_obj instanceof EE_Datetime_Field) {
+				$field_obj->set_timezone($this->_timezone);
+				if (isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime) {
+					EEH_DTT_Helper::setTimezone($this->_fields[ $field_name ], new DateTimeZone($this->_timezone));
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * This just returns whatever is set for the current timezone.
+	 *
+	 * @access public
+	 * @return string timezone string
+	 */
+	public function get_timezone()
+	{
+		return $this->_timezone;
+	}
+
+
+	/**
+	 * This sets the internal date format to what is sent in to be used as the new default for the class
+	 * internally instead of wp set date format options
+	 *
+	 * @since 4.6
+	 * @param string $format should be a format recognizable by PHP date() functions.
+	 */
+	public function set_date_format($format)
+	{
+		$this->_dt_frmt = $format;
+		// clear cached_properties because they won't be relevant now.
+		$this->_clear_cached_properties();
+	}
+
+
+	/**
+	 * This sets the internal time format string to what is sent in to be used as the new default for the
+	 * class internally instead of wp set time format options.
+	 *
+	 * @since 4.6
+	 * @param string $format should be a format recognizable by PHP date() functions.
+	 */
+	public function set_time_format($format)
+	{
+		$this->_tm_frmt = $format;
+		// clear cached_properties because they won't be relevant now.
+		$this->_clear_cached_properties();
+	}
+
+
+	/**
+	 * This returns the current internal set format for the date and time formats.
+	 *
+	 * @param bool $full           if true (default), then return the full format.  Otherwise will return an array
+	 *                             where the first value is the date format and the second value is the time format.
+	 * @return mixed string|array
+	 */
+	public function get_format($full = true)
+	{
+		return $full ? $this->_dt_frmt . ' ' . $this->_tm_frmt : array($this->_dt_frmt, $this->_tm_frmt);
+	}
+
+
+	/**
+	 * cache
+	 * stores the passed model object on the current model object.
+	 * In certain circumstances, we can use this cached model object instead of querying for another one entirely.
+	 *
+	 * @param string        $relationName    one of the keys in the _model_relations array on the model. Eg
+	 *                                       'Registration' associated with this model object
+	 * @param EE_Base_Class $object_to_cache that has a relation to this model object. (Eg, if this is a Transaction,
+	 *                                       that could be a payment or a registration)
+	 * @param null          $cache_id        a string or number that will be used as the key for any Belongs_To_Many
+	 *                                       items which will be stored in an array on this object
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return mixed    index into cache, or just TRUE if the relation is of type Belongs_To (because there's only one
+	 *                                       related thing, no array)
+	 */
+	public function cache($relationName = '', $object_to_cache = null, $cache_id = null)
+	{
+		// its entirely possible that there IS no related object yet in which case there is nothing to cache.
+		if (! $object_to_cache instanceof EE_Base_Class) {
+			return false;
+		}
+		// also get "how" the object is related, or throw an error
+		if (! $relationship_to_model = $this->get_model()->related_settings_for($relationName)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__('There is no relationship to %s on a %s. Cannot cache it', 'event_espresso'),
+					$relationName,
+					get_class($this)
+				)
+			);
+		}
+		// how many things are related ?
+		if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
+			// if it's a "belongs to" relationship, then there's only one related model object
+			// eg, if this is a registration, there's only 1 attendee for it
+			// so for these model objects just set it to be cached
+			$this->_model_relations[ $relationName ] = $object_to_cache;
+			$return = true;
+		} else {
+			// otherwise, this is the "many" side of a one to many relationship,
+			// so we'll add the object to the array of related objects for that type.
+			// eg: if this is an event, there are many registrations for that event,
+			// so we cache the registrations in an array
+			if (! is_array($this->_model_relations[ $relationName ])) {
+				// if for some reason, the cached item is a model object,
+				// then stick that in the array, otherwise start with an empty array
+				$this->_model_relations[ $relationName ] = $this->_model_relations[ $relationName ]
+														   instanceof
+														   EE_Base_Class
+					? array($this->_model_relations[ $relationName ]) : array();
+			}
+			// first check for a cache_id which is normally empty
+			if (! empty($cache_id)) {
+				// if the cache_id exists, then it means we are purposely trying to cache this
+				// with a known key that can then be used to retrieve the object later on
+				$this->_model_relations[ $relationName ][ $cache_id ] = $object_to_cache;
+				$return = $cache_id;
+			} elseif ($object_to_cache->ID()) {
+				// OR the cached object originally came from the db, so let's just use it's PK for an ID
+				$this->_model_relations[ $relationName ][ $object_to_cache->ID() ] = $object_to_cache;
+				$return = $object_to_cache->ID();
+			} else {
+				// OR it's a new object with no ID, so just throw it in the array with an auto-incremented ID
+				$this->_model_relations[ $relationName ][] = $object_to_cache;
+				// move the internal pointer to the end of the array
+				end($this->_model_relations[ $relationName ]);
+				// and grab the key so that we can return it
+				$return = key($this->_model_relations[ $relationName ]);
+			}
+		}
+		return $return;
+	}
+
+
+	/**
+	 * For adding an item to the cached_properties property.
+	 *
+	 * @access protected
+	 * @param string      $fieldname the property item the corresponding value is for.
+	 * @param mixed       $value     The value we are caching.
+	 * @param string|null $cache_type
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _set_cached_property($fieldname, $value, $cache_type = null)
+	{
+		// first make sure this property exists
+		$this->get_model()->field_settings_for($fieldname);
+		$cache_type = empty($cache_type) ? 'standard' : $cache_type;
+		$this->_cached_properties[ $fieldname ][ $cache_type ] = $value;
+	}
+
+
+	/**
+	 * This returns the value cached property if it exists OR the actual property value if the cache doesn't exist.
+	 * This also SETS the cache if we return the actual property!
+	 *
+	 * @param string $fieldname        the name of the property we're trying to retrieve
+	 * @param bool   $pretty
+	 * @param string $extra_cache_ref  This allows the user to specify an extra cache ref for the given property
+	 *                                 (in cases where the same property may be used for different outputs
+	 *                                 - i.e. datetime, money etc.)
+	 *                                 It can also accept certain pre-defined "schema" strings
+	 *                                 to define how to output the property.
+	 *                                 see the field's prepare_for_pretty_echoing for what strings can be used
+	 * @return mixed                   whatever the value for the property is we're retrieving
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _get_cached_property($fieldname, $pretty = false, $extra_cache_ref = null)
+	{
+		// verify the field exists
+		$model = $this->get_model();
+		$model->field_settings_for($fieldname);
+		$cache_type = $pretty ? 'pretty' : 'standard';
+		$cache_type .= ! empty($extra_cache_ref) ? '_' . $extra_cache_ref : '';
+		if (isset($this->_cached_properties[ $fieldname ][ $cache_type ])) {
+			return $this->_cached_properties[ $fieldname ][ $cache_type ];
+		}
+		$value = $this->_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
+		$this->_set_cached_property($fieldname, $value, $cache_type);
+		return $value;
+	}
+
+
+	/**
+	 * If the cache didn't fetch the needed item, this fetches it.
+	 *
+	 * @param string $fieldname
+	 * @param bool   $pretty
+	 * @param string $extra_cache_ref
+	 * @return mixed
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _get_fresh_property($fieldname, $pretty = false, $extra_cache_ref = null)
+	{
+		$field_obj = $this->get_model()->field_settings_for($fieldname);
+		// If this is an EE_Datetime_Field we need to make sure timezone, formats, and output are correct
+		if ($field_obj instanceof EE_Datetime_Field) {
+			$this->_prepare_datetime_field($field_obj, $pretty, $extra_cache_ref);
+		}
+		if (! isset($this->_fields[ $fieldname ])) {
+			$this->_fields[ $fieldname ] = null;
+		}
+		$value = $pretty
+			? $field_obj->prepare_for_pretty_echoing($this->_fields[ $fieldname ], $extra_cache_ref)
+			: $field_obj->prepare_for_get($this->_fields[ $fieldname ]);
+		return $value;
+	}
+
+
+	/**
+	 * set timezone, formats, and output for EE_Datetime_Field objects
+	 *
+	 * @param \EE_Datetime_Field $datetime_field
+	 * @param bool               $pretty
+	 * @param null               $date_or_time
+	 * @return void
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _prepare_datetime_field(
+		EE_Datetime_Field $datetime_field,
+		$pretty = false,
+		$date_or_time = null
+	) {
+		$datetime_field->set_timezone($this->_timezone);
+		$datetime_field->set_date_format($this->_dt_frmt, $pretty);
+		$datetime_field->set_time_format($this->_tm_frmt, $pretty);
+		// set the output returned
+		switch ($date_or_time) {
+			case 'D':
+				$datetime_field->set_date_time_output('date');
+				break;
+			case 'T':
+				$datetime_field->set_date_time_output('time');
+				break;
+			default:
+				$datetime_field->set_date_time_output();
+		}
+	}
+
+
+	/**
+	 * This just takes care of clearing out the cached_properties
+	 *
+	 * @return void
+	 */
+	protected function _clear_cached_properties()
+	{
+		$this->_cached_properties = array();
+	}
+
+
+	/**
+	 * This just clears out ONE property if it exists in the cache
+	 *
+	 * @param  string $property_name the property to remove if it exists (from the _cached_properties array)
+	 * @return void
+	 */
+	protected function _clear_cached_property($property_name)
+	{
+		if (isset($this->_cached_properties[ $property_name ])) {
+			unset($this->_cached_properties[ $property_name ]);
+		}
+	}
+
+
+	/**
+	 * Ensures that this related thing is a model object.
+	 *
+	 * @param mixed  $object_or_id EE_base_Class/int/string either a related model object, or its ID
+	 * @param string $model_name   name of the related thing, eg 'Attendee',
+	 * @return EE_Base_Class
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function ensure_related_thing_is_model_obj($object_or_id, $model_name)
+	{
+		$other_model_instance = self::_get_model_instance_with_name(
+			self::_get_model_classname($model_name),
+			$this->_timezone
+		);
+		return $other_model_instance->ensure_is_obj($object_or_id);
+	}
+
+
+	/**
+	 * Forgets the cached model of the given relation Name. So the next time we request it,
+	 * we will fetch it again from the database. (Handy if you know it's changed somehow).
+	 * If a specific object is supplied, and the relationship to it is either a HasMany or HABTM,
+	 * then only remove that one object from our cached array. Otherwise, clear the entire list
+	 *
+	 * @param string $relationName                         one of the keys in the _model_relations array on the model.
+	 *                                                     Eg 'Registration'
+	 * @param mixed  $object_to_remove_or_index_into_array or an index into the array of cached things, or NULL
+	 *                                                     if you intend to use $clear_all = TRUE, or the relation only
+	 *                                                     has 1 object anyways (ie, it's a BelongsToRelation)
+	 * @param bool   $clear_all                            This flags clearing the entire cache relation property if
+	 *                                                     this is HasMany or HABTM.
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return EE_Base_Class | boolean from which was cleared from the cache, or true if we requested to remove a
+	 *                                                     relation from all
+	 */
+	public function clear_cache($relationName, $object_to_remove_or_index_into_array = null, $clear_all = false)
+	{
+		$relationship_to_model = $this->get_model()->related_settings_for($relationName);
+		$index_in_cache = '';
+		if (! $relationship_to_model) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__('There is no relationship to %s on a %s. Cannot clear that cache', 'event_espresso'),
+					$relationName,
+					get_class($this)
+				)
+			);
+		}
+		if ($clear_all) {
+			$obj_removed = true;
+			$this->_model_relations[ $relationName ] = null;
+		} elseif ($relationship_to_model instanceof EE_Belongs_To_Relation) {
+			$obj_removed = $this->_model_relations[ $relationName ];
+			$this->_model_relations[ $relationName ] = null;
+		} else {
+			if ($object_to_remove_or_index_into_array instanceof EE_Base_Class
+				&& $object_to_remove_or_index_into_array->ID()
+			) {
+				$index_in_cache = $object_to_remove_or_index_into_array->ID();
+				if (is_array($this->_model_relations[ $relationName ])
+					&& ! isset($this->_model_relations[ $relationName ][ $index_in_cache ])
+				) {
+					$index_found_at = null;
+					// find this object in the array even though it has a different key
+					foreach ($this->_model_relations[ $relationName ] as $index => $obj) {
+						/** @noinspection TypeUnsafeComparisonInspection */
+						if ($obj instanceof EE_Base_Class
+							&& (
+								$obj == $object_to_remove_or_index_into_array
+								|| $obj->ID() === $object_to_remove_or_index_into_array->ID()
+							)
+						) {
+							$index_found_at = $index;
+							break;
+						}
+					}
+					if ($index_found_at) {
+						$index_in_cache = $index_found_at;
+					} else {
+						// it wasn't found. huh. well obviously it doesn't need to be removed from teh cache
+						// if it wasn't in it to begin with. So we're done
+						return $object_to_remove_or_index_into_array;
+					}
+				}
+			} elseif ($object_to_remove_or_index_into_array instanceof EE_Base_Class) {
+				// so they provided a model object, but it's not yet saved to the DB... so let's go hunting for it!
+				foreach ($this->get_all_from_cache($relationName) as $index => $potentially_obj_we_want) {
+					/** @noinspection TypeUnsafeComparisonInspection */
+					if ($potentially_obj_we_want == $object_to_remove_or_index_into_array) {
+						$index_in_cache = $index;
+					}
+				}
+			} else {
+				$index_in_cache = $object_to_remove_or_index_into_array;
+			}
+			// supposedly we've found it. But it could just be that the client code
+			// provided a bad index/object
+			if (isset($this->_model_relations[ $relationName ][ $index_in_cache ])) {
+				$obj_removed = $this->_model_relations[ $relationName ][ $index_in_cache ];
+				unset($this->_model_relations[ $relationName ][ $index_in_cache ]);
+			} else {
+				// that thing was never cached anyways.
+				$obj_removed = null;
+			}
+		}
+		return $obj_removed;
+	}
+
+
+	/**
+	 * update_cache_after_object_save
+	 * Allows a cached item to have it's cache ID (within the array of cached items) reset using the new ID it has
+	 * obtained after being saved to the db
+	 *
+	 * @param string        $relationName       - the type of object that is cached
+	 * @param EE_Base_Class $newly_saved_object - the newly saved object to be re-cached
+	 * @param string        $current_cache_id   - the ID that was used when originally caching the object
+	 * @return boolean TRUE on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function update_cache_after_object_save(
+		$relationName,
+		EE_Base_Class $newly_saved_object,
+		$current_cache_id = ''
+	) {
+		// verify that incoming object is of the correct type
+		$obj_class = 'EE_' . $relationName;
+		if ($newly_saved_object instanceof $obj_class) {
+			/* @type EE_Base_Class $newly_saved_object */
+			// now get the type of relation
+			$relationship_to_model = $this->get_model()->related_settings_for($relationName);
+			// if this is a 1:1 relationship
+			if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
+				// then just replace the cached object with the newly saved object
+				$this->_model_relations[ $relationName ] = $newly_saved_object;
+				return true;
+				// or if it's some kind of sordid feral polyamorous relationship...
+			}
+			if (is_array($this->_model_relations[ $relationName ])
+				&& isset($this->_model_relations[ $relationName ][ $current_cache_id ])
+			) {
+				// then remove the current cached item
+				unset($this->_model_relations[ $relationName ][ $current_cache_id ]);
+				// and cache the newly saved object using it's new ID
+				$this->_model_relations[ $relationName ][ $newly_saved_object->ID() ] = $newly_saved_object;
+				return true;
+			}
+		}
+		return false;
+	}
+
+
+	/**
+	 * Fetches a single EE_Base_Class on that relation. (If the relation is of type
+	 * BelongsTo, it will only ever have 1 object. However, other relations could have an array of objects)
+	 *
+	 * @param string $relationName
+	 * @return EE_Base_Class
+	 */
+	public function get_one_from_cache($relationName)
+	{
+		$cached_array_or_object = isset($this->_model_relations[ $relationName ])
+			? $this->_model_relations[ $relationName ]
+			: null;
+		if (is_array($cached_array_or_object)) {
+			return array_shift($cached_array_or_object);
+		}
+		return $cached_array_or_object;
+	}
+
+
+	/**
+	 * Fetches a single EE_Base_Class on that relation. (If the relation is of type
+	 * BelongsTo, it will only ever have 1 object. However, other relations could have an array of objects)
+	 *
+	 * @param string $relationName
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return EE_Base_Class[] NOT necessarily indexed by primary keys
+	 */
+	public function get_all_from_cache($relationName)
+	{
+		$objects = isset($this->_model_relations[ $relationName ]) ? $this->_model_relations[ $relationName ] : array();
+		// if the result is not an array, but exists, make it an array
+		$objects = is_array($objects) ? $objects : array($objects);
+		// bugfix for https://events.codebasehq.com/projects/event-espresso/tickets/7143
+		// basically, if this model object was stored in the session, and these cached model objects
+		// already have IDs, let's make sure they're in their model's entity mapper
+		// otherwise we will have duplicates next time we call
+		// EE_Registry::instance()->load_model( $relationName )->get_one_by_ID( $result->ID() );
+		$model = EE_Registry::instance()->load_model($relationName);
+		foreach ($objects as $model_object) {
+			if ($model instanceof EEM_Base && $model_object instanceof EE_Base_Class) {
+				// ensure its in the map if it has an ID; otherwise it will be added to the map when its saved
+				if ($model_object->ID()) {
+					$model->add_to_entity_map($model_object);
+				}
+			} else {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Error retrieving related model objects. Either $1%s is not a model or $2%s is not a model object',
+							'event_espresso'
+						),
+						$relationName,
+						gettype($model_object)
+					)
+				);
+			}
+		}
+		return $objects;
+	}
+
+
+	/**
+	 * Returns the next x number of EE_Base_Class objects in sequence from this object as found in the database
+	 * matching the given query conditions.
+	 *
+	 * @param null  $field_to_order_by  What field is being used as the reference point.
+	 * @param int   $limit              How many objects to return.
+	 * @param array $query_params       Any additional conditions on the query.
+	 * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
+	 *                                  you can indicate just the columns you want returned
+	 * @return array|EE_Base_Class[]
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function next_x($field_to_order_by = null, $limit = 1, $query_params = array(), $columns_to_select = null)
+	{
+		$model = $this->get_model();
+		$field = empty($field_to_order_by) && $model->has_primary_key_field()
+			? $model->get_primary_key_field()->get_name()
+			: $field_to_order_by;
+		$current_value = ! empty($field) ? $this->get($field) : null;
+		if (empty($field) || empty($current_value)) {
+			return array();
+		}
+		return $model->next_x($current_value, $field, $limit, $query_params, $columns_to_select);
+	}
+
+
+	/**
+	 * Returns the previous x number of EE_Base_Class objects in sequence from this object as found in the database
+	 * matching the given query conditions.
+	 *
+	 * @param null  $field_to_order_by  What field is being used as the reference point.
+	 * @param int   $limit              How many objects to return.
+	 * @param array $query_params       Any additional conditions on the query.
+	 * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
+	 *                                  you can indicate just the columns you want returned
+	 * @return array|EE_Base_Class[]
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function previous_x(
+		$field_to_order_by = null,
+		$limit = 1,
+		$query_params = array(),
+		$columns_to_select = null
+	) {
+		$model = $this->get_model();
+		$field = empty($field_to_order_by) && $model->has_primary_key_field()
+			? $model->get_primary_key_field()->get_name()
+			: $field_to_order_by;
+		$current_value = ! empty($field) ? $this->get($field) : null;
+		if (empty($field) || empty($current_value)) {
+			return array();
+		}
+		return $model->previous_x($current_value, $field, $limit, $query_params, $columns_to_select);
+	}
+
+
+	/**
+	 * Returns the next EE_Base_Class object in sequence from this object as found in the database
+	 * matching the given query conditions.
+	 *
+	 * @param null  $field_to_order_by  What field is being used as the reference point.
+	 * @param array $query_params       Any additional conditions on the query.
+	 * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
+	 *                                  you can indicate just the columns you want returned
+	 * @return array|EE_Base_Class
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function next($field_to_order_by = null, $query_params = array(), $columns_to_select = null)
+	{
+		$model = $this->get_model();
+		$field = empty($field_to_order_by) && $model->has_primary_key_field()
+			? $model->get_primary_key_field()->get_name()
+			: $field_to_order_by;
+		$current_value = ! empty($field) ? $this->get($field) : null;
+		if (empty($field) || empty($current_value)) {
+			return array();
+		}
+		return $model->next($current_value, $field, $query_params, $columns_to_select);
+	}
+
+
+	/**
+	 * Returns the previous EE_Base_Class object in sequence from this object as found in the database
+	 * matching the given query conditions.
+	 *
+	 * @param null  $field_to_order_by  What field is being used as the reference point.
+	 * @param array $query_params       Any additional conditions on the query.
+	 * @param null  $columns_to_select  If left null, then an EE_Base_Class object is returned, otherwise
+	 *                                  you can indicate just the column you want returned
+	 * @return array|EE_Base_Class
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function previous($field_to_order_by = null, $query_params = array(), $columns_to_select = null)
+	{
+		$model = $this->get_model();
+		$field = empty($field_to_order_by) && $model->has_primary_key_field()
+			? $model->get_primary_key_field()->get_name()
+			: $field_to_order_by;
+		$current_value = ! empty($field) ? $this->get($field) : null;
+		if (empty($field) || empty($current_value)) {
+			return array();
+		}
+		return $model->previous($current_value, $field, $query_params, $columns_to_select);
+	}
+
+
+	/**
+	 * Overrides parent because parent expects old models.
+	 * This also doesn't do any validation, and won't work for serialized arrays
+	 *
+	 * @param string $field_name
+	 * @param mixed  $field_value_from_db
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_from_db($field_name, $field_value_from_db)
+	{
+		$field_obj = $this->get_model()->field_settings_for($field_name);
+		if ($field_obj instanceof EE_Model_Field_Base) {
+			// you would think the DB has no NULLs for non-null label fields right? wrong!
+			// eg, a CPT model object could have an entry in the posts table, but no
+			// entry in the meta table. Meaning that all its columns in the meta table
+			// are null! yikes! so when we find one like that, use defaults for its meta columns
+			if ($field_value_from_db === null) {
+				if ($field_obj->is_nullable()) {
+					// if the field allows nulls, then let it be null
+					$field_value = null;
+				} else {
+					$field_value = $field_obj->get_default_value();
+				}
+			} else {
+				$field_value = $field_obj->prepare_for_set_from_db($field_value_from_db);
+			}
+			$this->_fields[ $field_name ] = $field_value;
+			$this->_clear_cached_property($field_name);
+		}
+	}
+
+
+	/**
+	 * verifies that the specified field is of the correct type
+	 *
+	 * @param string $field_name
+	 * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
+	 *                                (in cases where the same property may be used for different outputs
+	 *                                - i.e. datetime, money etc.)
+	 * @return mixed
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get($field_name, $extra_cache_ref = null)
+	{
+		return $this->_get_cached_property($field_name, false, $extra_cache_ref);
+	}
+
+
+	/**
+	 * This method simply returns the RAW unprocessed value for the given property in this class
+	 *
+	 * @param  string $field_name A valid fieldname
+	 * @return mixed              Whatever the raw value stored on the property is.
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error if fieldSettings is misconfigured or the field doesn't exist.
+	 */
+	public function get_raw($field_name)
+	{
+		$field_settings = $this->get_model()->field_settings_for($field_name);
+		return $field_settings instanceof EE_Datetime_Field && $this->_fields[ $field_name ] instanceof DateTime
+			? $this->_fields[ $field_name ]->format('U')
+			: $this->_fields[ $field_name ];
+	}
+
+
+	/**
+	 * This is used to return the internal DateTime object used for a field that is a
+	 * EE_Datetime_Field.
+	 *
+	 * @param string $field_name               The field name retrieving the DateTime object.
+	 * @return mixed null | false | DateTime  If the requested field is NOT a EE_Datetime_Field then
+	 * @throws EE_Error an error is set and false returned.  If the field IS an
+	 *                                         EE_Datetime_Field and but the field value is null, then
+	 *                                         just null is returned (because that indicates that likely
+	 *                                         this field is nullable).
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_DateTime_object($field_name)
+	{
+		$field_settings = $this->get_model()->field_settings_for($field_name);
+		if (! $field_settings instanceof EE_Datetime_Field) {
+			EE_Error::add_error(
+				sprintf(
+					esc_html__(
+						'The field %s is not an EE_Datetime_Field field.  There is no DateTime object stored on this field type.',
+						'event_espresso'
+					),
+					$field_name
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return false;
+		}
+		return isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime
+			? clone $this->_fields[ $field_name ]
+			: null;
+	}
+
+
+	/**
+	 * To be used in template to immediately echo out the value, and format it for output.
+	 * Eg, should call stripslashes and whatnot before echoing
+	 *
+	 * @param string $field_name      the name of the field as it appears in the DB
+	 * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
+	 *                                (in cases where the same property may be used for different outputs
+	 *                                - i.e. datetime, money etc.)
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e($field_name, $extra_cache_ref = null)
+	{
+		echo $this->get_pretty($field_name, $extra_cache_ref);
+	}
+
+
+	/**
+	 * Exactly like e(), echoes out the field, but sets its schema to 'form_input', so that it
+	 * can be easily used as the value of form input.
+	 *
+	 * @param string $field_name
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function f($field_name)
+	{
+		$this->e($field_name, 'form_input');
+	}
+
+
+	/**
+	 * Same as `f()` but just returns the value instead of echoing it
+	 *
+	 * @param string $field_name
+	 * @return string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_f($field_name)
+	{
+		return (string) $this->get_pretty($field_name, 'form_input');
+	}
+
+
+	/**
+	 * Gets a pretty view of the field's value. $extra_cache_ref can specify different formats for this.
+	 * The $extra_cache_ref will be passed to the model field's prepare_for_pretty_echoing, so consult the field's class
+	 * to see what options are available.
+	 *
+	 * @param string $field_name
+	 * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
+	 *                                (in cases where the same property may be used for different outputs
+	 *                                - i.e. datetime, money etc.)
+	 * @return mixed
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_pretty($field_name, $extra_cache_ref = null)
+	{
+		return $this->_get_cached_property($field_name, true, $extra_cache_ref);
+	}
+
+
+	/**
+	 * This simply returns the datetime for the given field name
+	 * Note: this protected function is called by the wrapper get_date or get_time or get_datetime functions
+	 * (and the equivalent e_date, e_time, e_datetime).
+	 *
+	 * @access   protected
+	 * @param string   $field_name   Field on the instantiated EE_Base_Class child object
+	 * @param string   $dt_frmt      valid datetime format used for date
+	 *                               (if '' then we just use the default on the field,
+	 *                               if NULL we use the last-used format)
+	 * @param string   $tm_frmt      Same as above except this is for time format
+	 * @param string   $date_or_time if NULL then both are returned, otherwise "D" = only date and "T" = only time.
+	 * @param  boolean $echo         Whether the dtt is echoing using pretty echoing or just returned using vanilla get
+	 * @return string|bool|EE_Error string on success, FALSE on fail, or EE_Error Exception is thrown
+	 *                               if field is not a valid dtt field, or void if echoing
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _get_datetime($field_name, $dt_frmt = '', $tm_frmt = '', $date_or_time = '', $echo = false)
+	{
+		// clear cached property
+		$this->_clear_cached_property($field_name);
+		// reset format properties because they are used in get()
+		$this->_dt_frmt = $dt_frmt !== '' ? $dt_frmt : $this->_dt_frmt;
+		$this->_tm_frmt = $tm_frmt !== '' ? $tm_frmt : $this->_tm_frmt;
+		if ($echo) {
+			$this->e($field_name, $date_or_time);
+			return '';
+		}
+		return $this->get($field_name, $date_or_time);
+	}
+
+
+	/**
+	 * below are wrapper functions for the various datetime outputs that can be obtained for JUST returning the date
+	 * portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
+	 * other echoes the pretty value for dtt)
+	 *
+	 * @param  string $field_name name of model object datetime field holding the value
+	 * @param  string $format     format for the date returned (if NULL we use default in dt_frmt property)
+	 * @return string            datetime value formatted
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_date($field_name, $format = '')
+	{
+		return $this->_get_datetime($field_name, $format, null, 'D');
+	}
+
+
+	/**
+	 * @param        $field_name
+	 * @param string $format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_date($field_name, $format = '')
+	{
+		$this->_get_datetime($field_name, $format, null, 'D', true);
+	}
+
+
+	/**
+	 * below are wrapper functions for the various datetime outputs that can be obtained for JUST returning the time
+	 * portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
+	 * other echoes the pretty value for dtt)
+	 *
+	 * @param  string $field_name name of model object datetime field holding the value
+	 * @param  string $format     format for the time returned ( if NULL we use default in tm_frmt property)
+	 * @return string             datetime value formatted
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_time($field_name, $format = '')
+	{
+		return $this->_get_datetime($field_name, null, $format, 'T');
+	}
+
+
+	/**
+	 * @param        $field_name
+	 * @param string $format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_time($field_name, $format = '')
+	{
+		$this->_get_datetime($field_name, null, $format, 'T', true);
+	}
+
+
+	/**
+	 * below are wrapper functions for the various datetime outputs that can be obtained for returning the date AND
+	 * time portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
+	 * other echoes the pretty value for dtt)
+	 *
+	 * @param  string $field_name name of model object datetime field holding the value
+	 * @param  string $dt_frmt    format for the date returned (if NULL we use default in dt_frmt property)
+	 * @param  string $tm_frmt    format for the time returned (if NULL we use default in tm_frmt property)
+	 * @return string             datetime value formatted
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_datetime($field_name, $dt_frmt = '', $tm_frmt = '')
+	{
+		return $this->_get_datetime($field_name, $dt_frmt, $tm_frmt);
+	}
+
+
+	/**
+	 * @param string $field_name
+	 * @param string $dt_frmt
+	 * @param string $tm_frmt
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_datetime($field_name, $dt_frmt = '', $tm_frmt = '')
+	{
+		$this->_get_datetime($field_name, $dt_frmt, $tm_frmt, null, true);
+	}
+
+
+	/**
+	 * Get the i8ln value for a date using the WordPress @see date_i18n function.
+	 *
+	 * @param string $field_name The EE_Datetime_Field reference for the date being retrieved.
+	 * @param string $format     PHP valid date/time string format.  If none is provided then the internal set format
+	 *                           on the object will be used.
+	 * @return string Date and time string in set locale or false if no field exists for the given
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 *                           field name.
+	 */
+	public function get_i18n_datetime($field_name, $format = '')
+	{
+		$format = empty($format) ? $this->_dt_frmt . ' ' . $this->_tm_frmt : $format;
+		return date_i18n(
+			$format,
+			EEH_DTT_Helper::get_timestamp_with_offset(
+				$this->get_raw($field_name),
+				$this->_timezone
+			)
+		);
+	}
+
+
+	/**
+	 * This method validates whether the given field name is a valid field on the model object as well as it is of a
+	 * type EE_Datetime_Field.  On success there will be returned the field settings.  On fail an EE_Error exception is
+	 * thrown.
+	 *
+	 * @param  string $field_name The field name being checked
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return EE_Datetime_Field
+	 */
+	protected function _get_dtt_field_settings($field_name)
+	{
+		$field = $this->get_model()->field_settings_for($field_name);
+		// check if field is dtt
+		if ($field instanceof EE_Datetime_Field) {
+			return $field;
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					'The field name "%s" has been requested for the EE_Base_Class datetime functions and it is not a valid EE_Datetime_Field.  Please check the spelling of the field and make sure it has been setup as a EE_Datetime_Field in the %s model constructor',
+					'event_espresso'
+				),
+				$field_name,
+				self::_get_model_classname(get_class($this))
+			)
+		);
+	}
+
+
+
+
+	/**
+	 * NOTE ABOUT BELOW:
+	 * These convenience date and time setters are for setting date and time independently.  In other words you might
+	 * want to change the time on a datetime_field but leave the date the same (or vice versa). IF on the other hand
+	 * you want to set both date and time at the same time, you can just use the models default set($fieldname,$value)
+	 * method and make sure you send the entire datetime value for setting.
+	 */
+	/**
+	 * sets the time on a datetime property
+	 *
+	 * @access protected
+	 * @param string|Datetime $time      a valid time string for php datetime functions (or DateTime object)
+	 * @param string          $fieldname the name of the field the time is being set on (must match a EE_Datetime_Field)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _set_time_for($time, $fieldname)
+	{
+		$this->_set_date_time('T', $time, $fieldname);
+	}
+
+
+	/**
+	 * sets the date on a datetime property
+	 *
+	 * @access protected
+	 * @param string|DateTime $date      a valid date string for php datetime functions ( or DateTime object)
+	 * @param string          $fieldname the name of the field the date is being set on (must match a EE_Datetime_Field)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _set_date_for($date, $fieldname)
+	{
+		$this->_set_date_time('D', $date, $fieldname);
+	}
+
+
+	/**
+	 * This takes care of setting a date or time independently on a given model object property. This method also
+	 * verifies that the given fieldname matches a model object property and is for a EE_Datetime_Field field
+	 *
+	 * @access protected
+	 * @param string          $what           "T" for time, 'B' for both, 'D' for Date.
+	 * @param string|DateTime $datetime_value A valid Date or Time string (or DateTime object)
+	 * @param string          $fieldname      the name of the field the date OR time is being set on (must match a
+	 *                                        EE_Datetime_Field property)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _set_date_time($what = 'T', $datetime_value, $fieldname)
+	{
+		$field = $this->_get_dtt_field_settings($fieldname);
+		$field->set_timezone($this->_timezone);
+		$field->set_date_format($this->_dt_frmt);
+		$field->set_time_format($this->_tm_frmt);
+		switch ($what) {
+			case 'T':
+				$this->_fields[ $fieldname ] = $field->prepare_for_set_with_new_time(
+					$datetime_value,
+					$this->_fields[ $fieldname ]
+				);
+				break;
+			case 'D':
+				$this->_fields[ $fieldname ] = $field->prepare_for_set_with_new_date(
+					$datetime_value,
+					$this->_fields[ $fieldname ]
+				);
+				break;
+			case 'B':
+				$this->_fields[ $fieldname ] = $field->prepare_for_set($datetime_value);
+				break;
+		}
+		$this->_clear_cached_property($fieldname);
+	}
+
+
+	/**
+	 * This will return a timestamp for the website timezone but ONLY when the current website timezone is different
+	 * than the timezone set for the website. NOTE, this currently only works well with methods that return values.  If
+	 * you use it with methods that echo values the $_timestamp property may not get reset to its original value and
+	 * that could lead to some unexpected results!
+	 *
+	 * @access public
+	 * @param string $field_name               This is the name of the field on the object that contains the date/time
+	 *                                         value being returned.
+	 * @param string $callback                 must match a valid method in this class (defaults to get_datetime)
+	 * @param mixed (array|string) $args       This is the arguments that will be passed to the callback.
+	 * @param string $prepend                  You can include something to prepend on the timestamp
+	 * @param string $append                   You can include something to append on the timestamp
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return string timestamp
+	 */
+	public function display_in_my_timezone(
+		$field_name,
+		$callback = 'get_datetime',
+		$args = null,
+		$prepend = '',
+		$append = ''
+	) {
+		$timezone = EEH_DTT_Helper::get_timezone();
+		if ($timezone === $this->_timezone) {
+			return '';
+		}
+		$original_timezone = $this->_timezone;
+		$this->set_timezone($timezone);
+		$fn = (array) $field_name;
+		$args = array_merge($fn, (array) $args);
+		if (! method_exists($this, $callback)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'The method named "%s" given as the callback param in "display_in_my_timezone" does not exist.  Please check your spelling',
+						'event_espresso'
+					),
+					$callback
+				)
+			);
+		}
+		$args = (array) $args;
+		$return = $prepend . call_user_func_array(array($this, $callback), $args) . $append;
+		$this->set_timezone($original_timezone);
+		return $return;
+	}
+
+
+	/**
+	 * Deletes this model object.
+	 * This calls the `EE_Base_Class::_delete` method.  Child classes wishing to change default behaviour should
+	 * override
+	 * `EE_Base_Class::_delete` NOT this class.
+	 *
+	 * @return boolean | int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function delete()
+	{
+		/**
+		 * Called just before the `EE_Base_Class::_delete` method call.
+		 * Note:
+		 * `EE_Base_Class::_delete` might be overridden by child classes so any client code hooking into these actions
+		 * should be aware that `_delete` may not always result in a permanent delete.
+		 * For example, `EE_Soft_Delete_Base_Class::_delete`
+		 * soft deletes (trash) the object and does not permanently delete it.
+		 *
+		 * @param EE_Base_Class $model_object about to be 'deleted'
+		 */
+		do_action('AHEE__EE_Base_Class__delete__before', $this);
+		$result = $this->_delete();
+		/**
+		 * Called just after the `EE_Base_Class::_delete` method call.
+		 * Note:
+		 * `EE_Base_Class::_delete` might be overridden by child classes so any client code hooking into these actions
+		 * should be aware that `_delete` may not always result in a permanent delete.
+		 * For example `EE_Soft_Base_Class::_delete`
+		 * soft deletes (trash) the object and does not permanently delete it.
+		 *
+		 * @param EE_Base_Class $model_object that was just 'deleted'
+		 * @param boolean       $result
+		 */
+		do_action('AHEE__EE_Base_Class__delete__end', $this, $result);
+		return $result;
+	}
+
+
+	/**
+	 * Calls the specific delete method for the instantiated class.
+	 * This method is called by the public `EE_Base_Class::delete` method.  Any child classes desiring to override
+	 * default functionality for "delete" (which is to call `permanently_delete`) should override this method NOT
+	 * `EE_Base_Class::delete`
+	 *
+	 * @return bool|int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _delete()
+	{
+		return $this->delete_permanently();
+	}
+
+
+	/**
+	 * Deletes this model object permanently from db
+	 * (but keep in mind related models may block the delete and return an error)
+	 *
+	 * @return bool | int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function delete_permanently()
+	{
+		/**
+		 * Called just before HARD deleting a model object
+		 *
+		 * @param EE_Base_Class $model_object about to be 'deleted'
+		 */
+		do_action('AHEE__EE_Base_Class__delete_permanently__before', $this);
+		$model = $this->get_model();
+		$result = $model->delete_permanently_by_ID($this->ID());
+		$this->refresh_cache_of_related_objects();
+		/**
+		 * Called just after HARD deleting a model object
+		 *
+		 * @param EE_Base_Class $model_object that was just 'deleted'
+		 * @param boolean       $result
+		 */
+		do_action('AHEE__EE_Base_Class__delete_permanently__end', $this, $result);
+		return $result;
+	}
+
+
+	/**
+	 * When this model object is deleted, it may still be cached on related model objects. This clears the cache of
+	 * related model objects
+	 *
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function refresh_cache_of_related_objects()
+	{
+		$model = $this->get_model();
+		foreach ($model->relation_settings() as $relation_name => $relation_obj) {
+			if (! empty($this->_model_relations[ $relation_name ])) {
+				$related_objects = $this->_model_relations[ $relation_name ];
+				if ($relation_obj instanceof EE_Belongs_To_Relation) {
+					// this relation only stores a single model object, not an array
+					// but let's make it consistent
+					$related_objects = array($related_objects);
+				}
+				foreach ($related_objects as $related_object) {
+					// only refresh their cache if they're in memory
+					if ($related_object instanceof EE_Base_Class) {
+						$related_object->clear_cache(
+							$model->get_this_model_name(),
+							$this
+						);
+					}
+				}
+			}
+		}
+	}
+
+
+	/**
+	 *        Saves this object to the database. An array may be supplied to set some values on this
+	 * object just before saving.
+	 *
+	 * @access public
+	 * @param array $set_cols_n_values keys are field names, values are their new values,
+	 *                                 if provided during the save() method (often client code will change the fields'
+	 *                                 values before calling save)
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return int , 1 on a successful update, the ID of the new entry on insert; 0 on failure or if the model object
+	 *                                 isn't allowed to persist (as determined by EE_Base_Class::allow_persist())
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 */
+	public function save($set_cols_n_values = array())
+	{
+		$model = $this->get_model();
+		/**
+		 * Filters the fields we're about to save on the model object
+		 *
+		 * @param array         $set_cols_n_values
+		 * @param EE_Base_Class $model_object
+		 */
+		$set_cols_n_values = (array) apply_filters(
+			'FHEE__EE_Base_Class__save__set_cols_n_values',
+			$set_cols_n_values,
+			$this
+		);
+		// set attributes as provided in $set_cols_n_values
+		foreach ($set_cols_n_values as $column => $value) {
+			$this->set($column, $value);
+		}
+		// no changes ? then don't do anything
+		if (! $this->_has_changes && $this->ID() && $model->get_primary_key_field()->is_auto_increment()) {
+			return 0;
+		}
+		/**
+		 * Saving a model object.
+		 * Before we perform a save, this action is fired.
+		 *
+		 * @param EE_Base_Class $model_object the model object about to be saved.
+		 */
+		do_action('AHEE__EE_Base_Class__save__begin', $this);
+		if (! $this->allow_persist()) {
+			return 0;
+		}
+		// now get current attribute values
+		$save_cols_n_values = $this->_fields;
+		// if the object already has an ID, update it. Otherwise, insert it
+		// also: change the assumption about values passed to the model NOT being prepare dby the model object.
+		// They have been
+		$old_assumption_concerning_value_preparation = $model
+			->get_assumption_concerning_values_already_prepared_by_model_object();
+		$model->assume_values_already_prepared_by_model_object(true);
+		// does this model have an autoincrement PK?
+		if ($model->has_primary_key_field()) {
+			if ($model->get_primary_key_field()->is_auto_increment()) {
+				// ok check if it's set, if so: update; if not, insert
+				if (! empty($save_cols_n_values[ $model->primary_key_name() ])) {
+					$results = $model->update_by_ID($save_cols_n_values, $this->ID());
+				} else {
+					unset($save_cols_n_values[ $model->primary_key_name() ]);
+					$results = $model->insert($save_cols_n_values);
+					if ($results) {
+						// if successful, set the primary key
+						// but don't use the normal SET method, because it will check if
+						// an item with the same ID exists in the mapper & db, then
+						// will find it in the db (because we just added it) and THAT object
+						// will get added to the mapper before we can add this one!
+						// but if we just avoid using the SET method, all that headache can be avoided
+						$pk_field_name = $model->primary_key_name();
+						$this->_fields[ $pk_field_name ] = $results;
+						$this->_clear_cached_property($pk_field_name);
+						$model->add_to_entity_map($this);
+						$this->_update_cached_related_model_objs_fks();
+					}
+				}
+			} else {// PK is NOT auto-increment
+				// so check if one like it already exists in the db
+				if ($model->exists_by_ID($this->ID())) {
+					if (WP_DEBUG && ! $this->in_entity_map()) {
+						throw new EE_Error(
+							sprintf(
+								esc_html__(
+									'Using a model object %1$s that is NOT in the entity map, can lead to unexpected errors. You should either: %4$s 1. Put it in the entity mapper by calling %2$s %4$s 2. Discard this model object and use what is in the entity mapper %4$s 3. Fetch from the database using %3$s',
+									'event_espresso'
+								),
+								get_class($this),
+								get_class($model) . '::instance()->add_to_entity_map()',
+								get_class($model) . '::instance()->get_one_by_ID()',
+								'<br />'
+							)
+						);
+					}
+					$results = $model->update_by_ID($save_cols_n_values, $this->ID());
+				} else {
+					$results = $model->insert($save_cols_n_values);
+					$this->_update_cached_related_model_objs_fks();
+				}
+			}
+		} else {// there is NO primary key
+			$already_in_db = false;
+			foreach ($model->unique_indexes() as $index) {
+				$uniqueness_where_params = array_intersect_key($save_cols_n_values, $index->fields());
+				if ($model->exists(array($uniqueness_where_params))) {
+					$already_in_db = true;
+				}
+			}
+			if ($already_in_db) {
+				$combined_pk_fields_n_values = array_intersect_key(
+					$save_cols_n_values,
+					$model->get_combined_primary_key_fields()
+				);
+				$results = $model->update(
+					$save_cols_n_values,
+					$combined_pk_fields_n_values
+				);
+			} else {
+				$results = $model->insert($save_cols_n_values);
+			}
+		}
+		// restore the old assumption about values being prepared by the model object
+		$model->assume_values_already_prepared_by_model_object(
+			$old_assumption_concerning_value_preparation
+		);
+		/**
+		 * After saving the model object this action is called
+		 *
+		 * @param EE_Base_Class $model_object which was just saved
+		 * @param boolean|int   $results      if it were updated, TRUE or FALSE; if it were newly inserted
+		 *                                    the new ID (or 0 if an error occurred and it wasn't updated)
+		 */
+		do_action('AHEE__EE_Base_Class__save__end', $this, $results);
+		$this->_has_changes = false;
+		return $results;
+	}
+
+
+	/**
+	 * Updates the foreign key on related models objects pointing to this to have this model object's ID
+	 * as their foreign key.  If the cached related model objects already exist in the db, saves them (so that the DB
+	 * is consistent) Especially useful in case we JUST added this model object ot the database and we want to let its
+	 * cached relations with foreign keys to it know about that change. Eg: we've created a transaction but haven't
+	 * saved it to the db. We also create a registration and don't save it to the DB, but we DO cache it on the
+	 * transaction. Now, when we save the transaction, the registration's TXN_ID will be automatically updated, whether
+	 * or not they exist in the DB (if they do, their DB records will be automatically updated)
+	 *
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _update_cached_related_model_objs_fks()
+	{
+		$model = $this->get_model();
+		foreach ($model->relation_settings() as $relation_name => $relation_obj) {
+			if ($relation_obj instanceof EE_Has_Many_Relation) {
+				foreach ($this->get_all_from_cache($relation_name) as $related_model_obj_in_cache) {
+					$fk_to_this = $related_model_obj_in_cache->get_model()->get_foreign_key_to(
+						$model->get_this_model_name()
+					);
+					$related_model_obj_in_cache->set($fk_to_this->get_name(), $this->ID());
+					if ($related_model_obj_in_cache->ID()) {
+						$related_model_obj_in_cache->save();
+					}
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * Saves this model object and its NEW cached relations to the database.
+	 * (Meaning, for now, IT DOES NOT WORK if the cached items already exist in the DB.
+	 * In order for that to work, we would need to mark model objects as dirty/clean...
+	 * because otherwise, there's a potential for infinite looping of saving
+	 * Saves the cached related model objects, and ensures the relation between them
+	 * and this object and properly setup
+	 *
+	 * @return int ID of new model object on save; 0 on failure+
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function save_new_cached_related_model_objs()
+	{
+		// make sure this has been saved
+		if (! $this->ID()) {
+			$id = $this->save();
+		} else {
+			$id = $this->ID();
+		}
+		// now save all the NEW cached model objects  (ie they don't exist in the DB)
+		foreach ($this->get_model()->relation_settings() as $relationName => $relationObj) {
+			if ($this->_model_relations[ $relationName ]) {
+				// is this a relation where we should expect just ONE related object (ie, EE_Belongs_To_relation)
+				// or MANY related objects (ie, EE_HABTM_Relation or EE_Has_Many_Relation)?
+				/* @var $related_model_obj EE_Base_Class */
+				if ($relationObj instanceof EE_Belongs_To_Relation) {
+					// add a relation to that relation type (which saves the appropriate thing in the process)
+					// but ONLY if it DOES NOT exist in the DB
+					$related_model_obj = $this->_model_relations[ $relationName ];
+					// if( ! $related_model_obj->ID()){
+					$this->_add_relation_to($related_model_obj, $relationName);
+					$related_model_obj->save_new_cached_related_model_objs();
+					// }
+				} else {
+					foreach ($this->_model_relations[ $relationName ] as $related_model_obj) {
+						// add a relation to that relation type (which saves the appropriate thing in the process)
+						// but ONLY if it DOES NOT exist in the DB
+						// if( ! $related_model_obj->ID()){
+						$this->_add_relation_to($related_model_obj, $relationName);
+						$related_model_obj->save_new_cached_related_model_objs();
+						// }
+					}
+				}
+			}
+		}
+		return $id;
+	}
+
+
+	/**
+	 * for getting a model while instantiated.
+	 *
+	 * @return EEM_Base | EEM_CPT_Base
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_model()
+	{
+		if (! $this->_model) {
+			$modelName = self::_get_model_classname(get_class($this));
+			$this->_model = self::_get_model_instance_with_name($modelName, $this->_timezone);
+		} else {
+			$this->_model->set_timezone($this->_timezone);
+		}
+		return $this->_model;
+	}
+
+
+	/**
+	 * @param $props_n_values
+	 * @param $classname
+	 * @return mixed bool|EE_Base_Class|EEM_CPT_Base
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected static function _get_object_from_entity_mapper($props_n_values, $classname)
+	{
+		// TODO: will not work for Term_Relationships because they have no PK!
+		$primary_id_ref = self::_get_primary_key_name($classname);
+		if (array_key_exists($primary_id_ref, $props_n_values)
+			&& ! empty($props_n_values[ $primary_id_ref ])
+		) {
+			$id = $props_n_values[ $primary_id_ref ];
+			return self::_get_model($classname)->get_from_entity_map($id);
+		}
+		return false;
+	}
+
+
+	/**
+	 * This is called by child static "new_instance" method and we'll check to see if there is an existing db entry for
+	 * the primary key (if present in incoming values). If there is a key in the incoming array that matches the
+	 * primary key for the model AND it is not null, then we check the db. If there's a an object we return it.  If not
+	 * we return false.
+	 *
+	 * @param  array  $props_n_values   incoming array of properties and their values
+	 * @param  string $classname        the classname of the child class
+	 * @param null    $timezone
+	 * @param array   $date_formats     incoming date_formats in an array where the first value is the
+	 *                                  date_format and the second value is the time format
+	 * @return mixed (EE_Base_Class|bool)
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 */
+	protected static function _check_for_object($props_n_values, $classname, $timezone = null, $date_formats = array())
+	{
+		$existing = null;
+		$model = self::_get_model($classname, $timezone);
+		if ($model->has_primary_key_field()) {
+			$primary_id_ref = self::_get_primary_key_name($classname);
+			if (array_key_exists($primary_id_ref, $props_n_values)
+				&& ! empty($props_n_values[ $primary_id_ref ])
+			) {
+				$existing = $model->get_one_by_ID(
+					$props_n_values[ $primary_id_ref ]
+				);
+			}
+		} elseif ($model->has_all_combined_primary_key_fields($props_n_values)) {
+			// no primary key on this model, but there's still a matching item in the DB
+			$existing = self::_get_model($classname, $timezone)->get_one_by_ID(
+				self::_get_model($classname, $timezone)
+					->get_index_primary_key_string($props_n_values)
+			);
+		}
+		if ($existing) {
+			// set date formats if present before setting values
+			if (! empty($date_formats) && is_array($date_formats)) {
+				$existing->set_date_format($date_formats[0]);
+				$existing->set_time_format($date_formats[1]);
+			} else {
+				// set default formats for date and time
+				$existing->set_date_format(get_option('date_format'));
+				$existing->set_time_format(get_option('time_format'));
+			}
+			foreach ($props_n_values as $property => $field_value) {
+				$existing->set($property, $field_value);
+			}
+			return $existing;
+		}
+		return false;
+	}
+
+
+	/**
+	 * Gets the EEM_*_Model for this class
+	 *
+	 * @access public now, as this is more convenient
+	 * @param      $classname
+	 * @param null $timezone
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return EEM_Base
+	 */
+	protected static function _get_model($classname, $timezone = null)
+	{
+		// find model for this class
+		if (! $classname) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'What were you thinking calling _get_model(%s)?? You need to specify the class name',
+						'event_espresso'
+					),
+					$classname
+				)
+			);
+		}
+		$modelName = self::_get_model_classname($classname);
+		return self::_get_model_instance_with_name($modelName, $timezone);
+	}
+
+
+	/**
+	 * Gets the model instance (eg instance of EEM_Attendee) given its classname (eg EE_Attendee)
+	 *
+	 * @param string $model_classname
+	 * @param null   $timezone
+	 * @return EEM_Base
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected static function _get_model_instance_with_name($model_classname, $timezone = null)
+	{
+		$model_classname = str_replace('EEM_', '', $model_classname);
+		$model = EE_Registry::instance()->load_model($model_classname);
+		$model->set_timezone($timezone);
+		return $model;
+	}
+
+
+	/**
+	 * If a model name is provided (eg Registration), gets the model classname for that model.
+	 * Also works if a model class's classname is provided (eg EE_Registration).
+	 *
+	 * @param null $model_name
+	 * @return string like EEM_Attendee
+	 */
+	private static function _get_model_classname($model_name = null)
+	{
+		if (strpos($model_name, 'EE_') === 0) {
+			$model_classname = str_replace('EE_', 'EEM_', $model_name);
+		} else {
+			$model_classname = 'EEM_' . $model_name;
+		}
+		return $model_classname;
+	}
+
+
+	/**
+	 * returns the name of the primary key attribute
+	 *
+	 * @param null $classname
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return string
+	 */
+	protected static function _get_primary_key_name($classname = null)
+	{
+		if (! $classname) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__('What were you thinking calling _get_primary_key_name(%s)', 'event_espresso'),
+					$classname
+				)
+			);
+		}
+		return self::_get_model($classname)->get_primary_key_field()->get_name();
+	}
+
+
+	/**
+	 * Gets the value of the primary key.
+	 * If the object hasn't yet been saved, it should be whatever the model field's default was
+	 * (eg, if this were the EE_Event class, look at the primary key field on EEM_Event and see what its default value
+	 * is. Usually defaults for integer primary keys are 0; string primary keys are usually NULL).
+	 *
+	 * @return mixed, if the primary key is of type INT it'll be an int. Otherwise it could be a string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function ID()
+	{
+		$model = $this->get_model();
+		// now that we know the name of the variable, use a variable variable to get its value and return its
+		if ($model->has_primary_key_field()) {
+			return $this->_fields[ $model->primary_key_name() ];
+		}
+		return $model->get_index_primary_key_string($this->_fields);
+	}
+
+
+	/**
+	 * Adds a relationship to the specified EE_Base_Class object, given the relationship's name. Eg, if the current
+	 * model is related to a group of events, the $relationName should be 'Event', and should be a key in the EE
+	 * Model's $_model_relations array. If this model object doesn't exist in the DB, just caches the related thing
+	 *
+	 * @param mixed  $otherObjectModelObjectOrID       EE_Base_Class or the ID of the other object
+	 * @param string $relationName                     eg 'Events','Question',etc.
+	 *                                                 an attendee to a group, you also want to specify which role they
+	 *                                                 will have in that group. So you would use this parameter to
+	 *                                                 specify array('role-column-name'=>'role-id')
+	 * @param array  $extra_join_model_fields_n_values You can optionally include an array of key=>value pairs that
+	 *                                                 allow you to further constrict the relation to being added.
+	 *                                                 However, keep in mind that the columns (keys) given must match a
+	 *                                                 column on the JOIN table and currently only the HABTM models
+	 *                                                 accept these additional conditions.  Also remember that if an
+	 *                                                 exact match isn't found for these extra cols/val pairs, then a
+	 *                                                 NEW row is created in the join table.
+	 * @param null   $cache_id
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @return EE_Base_Class the object the relation was added to
+	 */
+	public function _add_relation_to(
+		$otherObjectModelObjectOrID,
+		$relationName,
+		$extra_join_model_fields_n_values = array(),
+		$cache_id = null
+	) {
+		$model = $this->get_model();
+		// if this thing exists in the DB, save the relation to the DB
+		if ($this->ID()) {
+			$otherObject = $model->add_relationship_to(
+				$this,
+				$otherObjectModelObjectOrID,
+				$relationName,
+				$extra_join_model_fields_n_values
+			);
+			// clear cache so future get_many_related and get_first_related() return new results.
+			$this->clear_cache($relationName, $otherObject, true);
+			if ($otherObject instanceof EE_Base_Class) {
+				$otherObject->clear_cache($model->get_this_model_name(), $this);
+			}
+		} else {
+			// this thing doesn't exist in the DB,  so just cache it
+			if (! $otherObjectModelObjectOrID instanceof EE_Base_Class) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Before a model object is saved to the database, calls to _add_relation_to must be passed an actual object, not just an ID. You provided %s as the model object to a %s',
+							'event_espresso'
+						),
+						$otherObjectModelObjectOrID,
+						get_class($this)
+					)
+				);
+			}
+			$otherObject = $otherObjectModelObjectOrID;
+			$this->cache($relationName, $otherObjectModelObjectOrID, $cache_id);
+		}
+		if ($otherObject instanceof EE_Base_Class) {
+			// fix the reciprocal relation too
+			if ($otherObject->ID()) {
+				// its saved so assumed relations exist in the DB, so we can just
+				// clear the cache so future queries use the updated info in the DB
+				$otherObject->clear_cache(
+					$model->get_this_model_name(),
+					null,
+					true
+				);
+			} else {
+				// it's not saved, so it caches relations like this
+				$otherObject->cache($model->get_this_model_name(), $this);
+			}
+		}
+		return $otherObject;
+	}
+
+
+	/**
+	 * Removes a relationship to the specified EE_Base_Class object, given the relationships' name. Eg, if the current
+	 * model is related to a group of events, the $relationName should be 'Events', and should be a key in the EE
+	 * Model's $_model_relations array. If this model object doesn't exist in the DB, just removes the related thing
+	 * from the cache
+	 *
+	 * @param mixed  $otherObjectModelObjectOrID
+	 *                EE_Base_Class or the ID of the other object, OR an array key into the cache if this isn't saved
+	 *                to the DB yet
+	 * @param string $relationName
+	 * @param array  $where_query
+	 *                You can optionally include an array of key=>value pairs that allow you to further constrict the
+	 *                relation to being added. However, keep in mind that the columns (keys) given must match a column
+	 *                on the JOIN table and currently only the HABTM models accept these additional conditions. Also
+	 *                remember that if an exact match isn't found for these extra cols/val pairs, then no row is
+	 *                deleted.
+	 * @return EE_Base_Class the relation was removed from
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function _remove_relation_to($otherObjectModelObjectOrID, $relationName, $where_query = array())
+	{
+		if ($this->ID()) {
+			// if this exists in the DB, save the relation change to the DB too
+			$otherObject = $this->get_model()->remove_relationship_to(
+				$this,
+				$otherObjectModelObjectOrID,
+				$relationName,
+				$where_query
+			);
+			$this->clear_cache(
+				$relationName,
+				$otherObject
+			);
+		} else {
+			// this doesn't exist in the DB, just remove it from the cache
+			$otherObject = $this->clear_cache(
+				$relationName,
+				$otherObjectModelObjectOrID
+			);
+		}
+		if ($otherObject instanceof EE_Base_Class) {
+			$otherObject->clear_cache(
+				$this->get_model()->get_this_model_name(),
+				$this
+			);
+		}
+		return $otherObject;
+	}
+
+
+	/**
+	 * Removes ALL the related things for the $relationName.
+	 *
+	 * @param string $relationName
+	 * @param array  $where_query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @return EE_Base_Class
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function _remove_relations($relationName, $where_query_params = array())
+	{
+		if ($this->ID()) {
+			// if this exists in the DB, save the relation change to the DB too
+			$otherObjects = $this->get_model()->remove_relations(
+				$this,
+				$relationName,
+				$where_query_params
+			);
+			$this->clear_cache(
+				$relationName,
+				null,
+				true
+			);
+		} else {
+			// this doesn't exist in the DB, just remove it from the cache
+			$otherObjects = $this->clear_cache(
+				$relationName,
+				null,
+				true
+			);
+		}
+		if (is_array($otherObjects)) {
+			foreach ($otherObjects as $otherObject) {
+				$otherObject->clear_cache(
+					$this->get_model()->get_this_model_name(),
+					$this
+				);
+			}
+		}
+		return $otherObjects;
+	}
+
+
+	/**
+	 * Gets all the related model objects of the specified type. Eg, if the current class if
+	 * EE_Event, you could call $this->get_many_related('Registration') to get an array of all the
+	 * EE_Registration objects which related to this event. Note: by default, we remove the "default query params"
+	 * because we want to get even deleted items etc.
+	 *
+	 * @param string $relationName key in the model's _model_relations array
+	 * @param array  $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @return EE_Base_Class[]     Results not necessarily indexed by IDs, because some results might not have primary
+	 *                             keys or might not be saved yet. Consider using EEM_Base::get_IDs() on these
+	 *                             results if you want IDs
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_many_related($relationName, $query_params = array())
+	{
+		if ($this->ID()) {
+			// this exists in the DB, so get the related things from either the cache or the DB
+			// if there are query parameters, forget about caching the related model objects.
+			if ($query_params) {
+				$related_model_objects = $this->get_model()->get_all_related(
+					$this,
+					$relationName,
+					$query_params
+				);
+			} else {
+				// did we already cache the result of this query?
+				$cached_results = $this->get_all_from_cache($relationName);
+				if (! $cached_results) {
+					$related_model_objects = $this->get_model()->get_all_related(
+						$this,
+						$relationName,
+						$query_params
+					);
+					// if no query parameters were passed, then we got all the related model objects
+					// for that relation. We can cache them then.
+					foreach ($related_model_objects as $related_model_object) {
+						$this->cache($relationName, $related_model_object);
+					}
+				} else {
+					$related_model_objects = $cached_results;
+				}
+			}
+		} else {
+			// this doesn't exist in the DB, so just get the related things from the cache
+			$related_model_objects = $this->get_all_from_cache($relationName);
+		}
+		return $related_model_objects;
+	}
+
+
+	/**
+	 * Instead of getting the related model objects, simply counts them. Ignores default_where_conditions by default,
+	 * unless otherwise specified in the $query_params
+	 *
+	 * @param string $relation_name  model_name like 'Event', or 'Registration'
+	 * @param array  $query_params   @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_count name of field to count by. By default, uses primary key
+	 * @param bool   $distinct       if we want to only count the distinct values for the column then you can trigger
+	 *                               that by the setting $distinct to TRUE;
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function count_related($relation_name, $query_params = array(), $field_to_count = null, $distinct = false)
+	{
+		return $this->get_model()->count_related(
+			$this,
+			$relation_name,
+			$query_params,
+			$field_to_count,
+			$distinct
+		);
+	}
+
+
+	/**
+	 * Instead of getting the related model objects, simply sums up the values of the specified field.
+	 * Note: ignores default_where_conditions by default, unless otherwise specified in the $query_params
+	 *
+	 * @param string $relation_name model_name like 'Event', or 'Registration'
+	 * @param array  $query_params  @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_sum  name of field to count by.
+	 *                              By default, uses primary key
+	 *                              (which doesn't make much sense, so you should probably change it)
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function sum_related($relation_name, $query_params = array(), $field_to_sum = null)
+	{
+		return $this->get_model()->sum_related(
+			$this,
+			$relation_name,
+			$query_params,
+			$field_to_sum
+		);
+	}
+
+
+	/**
+	 * Gets the first (ie, one) related model object of the specified type.
+	 *
+	 * @param string $relationName key in the model's _model_relations array
+	 * @param array  $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Base_Class (not an array, a single object)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_first_related($relationName, $query_params = array())
+	{
+		$model = $this->get_model();
+		if ($this->ID()) {// this exists in the DB, get from the cache OR the DB
+			// if they've provided some query parameters, don't bother trying to cache the result
+			// also make sure we're not caching the result of get_first_related
+			// on a relation which should have an array of objects (because the cache might have an array of objects)
+			if ($query_params
+				|| ! $model->related_settings_for($relationName)
+					 instanceof
+					 EE_Belongs_To_Relation
+			) {
+				$related_model_object = $model->get_first_related(
+					$this,
+					$relationName,
+					$query_params
+				);
+			} else {
+				// first, check if we've already cached the result of this query
+				$cached_result = $this->get_one_from_cache($relationName);
+				if (! $cached_result) {
+					$related_model_object = $model->get_first_related(
+						$this,
+						$relationName,
+						$query_params
+					);
+					$this->cache($relationName, $related_model_object);
+				} else {
+					$related_model_object = $cached_result;
+				}
+			}
+		} else {
+			$related_model_object = null;
+			// this doesn't exist in the Db,
+			// but maybe the relation is of type belongs to, and so the related thing might
+			if ($model->related_settings_for($relationName) instanceof EE_Belongs_To_Relation) {
+				$related_model_object = $model->get_first_related(
+					$this,
+					$relationName,
+					$query_params
+				);
+			}
+			// this doesn't exist in the DB and apparently the thing it belongs to doesn't either,
+			// just get what's cached on this object
+			if (! $related_model_object) {
+				$related_model_object = $this->get_one_from_cache($relationName);
+			}
+		}
+		return $related_model_object;
+	}
+
+
+	/**
+	 * Does a delete on all related objects of type $relationName and removes
+	 * the current model object's relation to them. If they can't be deleted (because
+	 * of blocking related model objects) does nothing. If the related model objects are
+	 * soft-deletable, they will be soft-deleted regardless of related blocking model objects.
+	 * If this model object doesn't exist yet in the DB, just removes its related things
+	 *
+	 * @param string $relationName
+	 * @param array  $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return int how many deleted
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function delete_related($relationName, $query_params = array())
+	{
+		if ($this->ID()) {
+			$count = $this->get_model()->delete_related(
+				$this,
+				$relationName,
+				$query_params
+			);
+		} else {
+			$count = count($this->get_all_from_cache($relationName));
+			$this->clear_cache($relationName, null, true);
+		}
+		return $count;
+	}
+
+
+	/**
+	 * Does a hard delete (ie, removes the DB row) on all related objects of type $relationName and removes
+	 * the current model object's relation to them. If they can't be deleted (because
+	 * of blocking related model objects) just does a soft delete on it instead, if possible.
+	 * If the related thing isn't a soft-deletable model object, this function is identical
+	 * to delete_related(). If this model object doesn't exist in the DB, just remove its related things
+	 *
+	 * @param string $relationName
+	 * @param array  $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return int how many deleted (including those soft deleted)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function delete_related_permanently($relationName, $query_params = array())
+	{
+		if ($this->ID()) {
+			$count = $this->get_model()->delete_related_permanently(
+				$this,
+				$relationName,
+				$query_params
+			);
+		} else {
+			$count = count($this->get_all_from_cache($relationName));
+		}
+		$this->clear_cache($relationName, null, true);
+		return $count;
+	}
+
+
+	/**
+	 * is_set
+	 * Just a simple utility function children can use for checking if property exists
+	 *
+	 * @access  public
+	 * @param  string $field_name property to check
+	 * @return bool                              TRUE if existing,FALSE if not.
+	 */
+	public function is_set($field_name)
+	{
+		return isset($this->_fields[ $field_name ]);
+	}
+
+
+	/**
+	 * Just a simple utility function children can use for checking if property (or properties) exists and throwing an
+	 * EE_Error exception if they don't
+	 *
+	 * @param  mixed (string|array) $properties properties to check
+	 * @throws EE_Error
+	 * @return bool                              TRUE if existing, throw EE_Error if not.
+	 */
+	protected function _property_exists($properties)
+	{
+		foreach ((array) $properties as $property_name) {
+			// first make sure this property exists
+			if (! $this->_fields[ $property_name ]) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Trying to retrieve a non-existent property (%s).  Double check the spelling please',
+							'event_espresso'
+						),
+						$property_name
+					)
+				);
+			}
+		}
+		return true;
+	}
+
+
+	/**
+	 * This simply returns an array of model fields for this object
+	 *
+	 * @return array
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function model_field_array()
+	{
+		$fields = $this->get_model()->field_settings(false);
+		$properties = array();
+		// remove prepended underscore
+		foreach ($fields as $field_name => $settings) {
+			$properties[ $field_name ] = $this->get($field_name);
+		}
+		return $properties;
+	}
+
+
+	/**
+	 * Very handy general function to allow for plugins to extend any child of EE_Base_Class.
+	 * If a method is called on a child of EE_Base_Class that doesn't exist, this function is called
+	 * (http://www.garfieldtech.com/blog/php-magic-call) and passed the method's name and arguments.
+	 * Instead of requiring a plugin to extend the EE_Base_Class
+	 * (which works fine is there's only 1 plugin, but when will that happen?)
+	 * they can add a hook onto 'filters_hook_espresso__{className}__{methodName}'
+	 * (eg, filters_hook_espresso__EE_Answer__my_great_function)
+	 * and accepts 2 arguments: the object on which the function was called,
+	 * and an array of the original arguments passed to the function.
+	 * Whatever their callback function returns will be returned by this function.
+	 * Example: in functions.php (or in a plugin):
+	 *      add_filter('FHEE__EE_Answer__my_callback','my_callback',10,3);
+	 *      function my_callback($previousReturnValue,EE_Base_Class $object,$argsArray){
+	 *          $returnString= "you called my_callback! and passed args:".implode(",",$argsArray);
+	 *          return $previousReturnValue.$returnString;
+	 *      }
+	 * require('EE_Answer.class.php');
+	 * $answer= EE_Answer::new_instance(array('REG_ID' => 2,'QST_ID' => 3,'ANS_value' => The answer is 42'));
+	 * echo $answer->my_callback('monkeys',100);
+	 * //will output "you called my_callback! and passed args:monkeys,100"
+	 *
+	 * @param string $methodName name of method which was called on a child of EE_Base_Class, but which
+	 * @param array  $args       array of original arguments passed to the function
+	 * @throws EE_Error
+	 * @return mixed whatever the plugin which calls add_filter decides
+	 */
+	public function __call($methodName, $args)
+	{
+		$className = get_class($this);
+		$tagName = "FHEE__{$className}__{$methodName}";
+		if (! has_filter($tagName)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"Method %s on class %s does not exist! You can create one with the following code in functions.php or in a plugin: add_filter('%s','my_callback',10,3);function my_callback(\$previousReturnValue,EE_Base_Class \$object, \$argsArray){/*function body*/return \$whatever;}",
+						'event_espresso'
+					),
+					$methodName,
+					$className,
+					$tagName
+				)
+			);
+		}
+		return apply_filters($tagName, null, $this, $args);
+	}
+
+
+	/**
+	 * Similar to insert_post_meta, adds a record in the Extra_Meta model's table with the given key and value.
+	 * A $previous_value can be specified in case there are many meta rows with the same key
+	 *
+	 * @param string $meta_key
+	 * @param mixed  $meta_value
+	 * @param mixed  $previous_value
+	 * @return bool|int # of records updated (or BOOLEAN if we actually ended up inserting the extra meta row)
+	 *                  NOTE: if the values haven't changed, returns 0
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function update_extra_meta($meta_key, $meta_value, $previous_value = null)
+	{
+		$query_params = array(
+			array(
+				'EXM_key'  => $meta_key,
+				'OBJ_ID'   => $this->ID(),
+				'EXM_type' => $this->get_model()->get_this_model_name(),
+			),
+		);
+		if ($previous_value !== null) {
+			$query_params[0]['EXM_value'] = $meta_value;
+		}
+		$existing_rows_like_that = EEM_Extra_Meta::instance()->get_all($query_params);
+		if (! $existing_rows_like_that) {
+			return $this->add_extra_meta($meta_key, $meta_value);
+		}
+		foreach ($existing_rows_like_that as $existing_row) {
+			$existing_row->save(array('EXM_value' => $meta_value));
+		}
+		return count($existing_rows_like_that);
+	}
+
+
+	/**
+	 * Adds a new extra meta record. If $unique is set to TRUE, we'll first double-check
+	 * no other extra meta for this model object have the same key. Returns TRUE if the
+	 * extra meta row was entered, false if not
+	 *
+	 * @param string  $meta_key
+	 * @param mixed   $meta_value
+	 * @param boolean $unique
+	 * @return boolean
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws ReflectionException
+	 */
+	public function add_extra_meta($meta_key, $meta_value, $unique = false)
+	{
+		if ($unique) {
+			$existing_extra_meta = EEM_Extra_Meta::instance()->get_one(
+				array(
+					array(
+						'EXM_key'  => $meta_key,
+						'OBJ_ID'   => $this->ID(),
+						'EXM_type' => $this->get_model()->get_this_model_name(),
+					),
+				)
+			);
+			if ($existing_extra_meta) {
+				return false;
+			}
+		}
+		$new_extra_meta = EE_Extra_Meta::new_instance(
+			array(
+				'EXM_key'   => $meta_key,
+				'EXM_value' => $meta_value,
+				'OBJ_ID'    => $this->ID(),
+				'EXM_type'  => $this->get_model()->get_this_model_name(),
+			)
+		);
+		$new_extra_meta->save();
+		return true;
+	}
+
+
+	/**
+	 * Deletes all the extra meta rows for this record as specified by key. If $meta_value
+	 * is specified, only deletes extra meta records with that value.
+	 *
+	 * @param string $meta_key
+	 * @param mixed  $meta_value
+	 * @return int number of extra meta rows deleted
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function delete_extra_meta($meta_key, $meta_value = null)
+	{
+		$query_params = array(
+			array(
+				'EXM_key'  => $meta_key,
+				'OBJ_ID'   => $this->ID(),
+				'EXM_type' => $this->get_model()->get_this_model_name(),
+			),
+		);
+		if ($meta_value !== null) {
+			$query_params[0]['EXM_value'] = $meta_value;
+		}
+		return EEM_Extra_Meta::instance()->delete($query_params);
+	}
+
+
+	/**
+	 * Gets the extra meta with the given meta key. If you specify "single" we just return 1, otherwise
+	 * an array of everything found. Requires that this model actually have a relation of type EE_Has_Many_Any_Relation.
+	 * You can specify $default is case you haven't found the extra meta
+	 *
+	 * @param string  $meta_key
+	 * @param boolean $single
+	 * @param mixed   $default if we don't find anything, what should we return?
+	 * @return mixed single value if $single; array if ! $single
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_extra_meta($meta_key, $single = false, $default = null)
+	{
+		if ($single) {
+			$result = $this->get_first_related(
+				'Extra_Meta',
+				array(array('EXM_key' => $meta_key))
+			);
+			if ($result instanceof EE_Extra_Meta) {
+				return $result->value();
+			}
+		} else {
+			$results = $this->get_many_related(
+				'Extra_Meta',
+				array(array('EXM_key' => $meta_key))
+			);
+			if ($results) {
+				$values = array();
+				foreach ($results as $result) {
+					if ($result instanceof EE_Extra_Meta) {
+						$values[ $result->ID() ] = $result->value();
+					}
+				}
+				return $values;
+			}
+		}
+		// if nothing discovered yet return default.
+		return apply_filters(
+			'FHEE__EE_Base_Class__get_extra_meta__default_value',
+			$default,
+			$meta_key,
+			$single,
+			$this
+		);
+	}
+
+
+	/**
+	 * Returns a simple array of all the extra meta associated with this model object.
+	 * If $one_of_each_key is true (Default), it will be an array of simple key-value pairs, keys being the
+	 * extra meta's key, and teh value being its value. However, if there are duplicate extra meta rows with
+	 * the same key, only one will be used. (eg array('foo'=>'bar','monkey'=>123))
+	 * If $one_of_each_key is false, it will return an array with the top-level keys being
+	 * the extra meta keys, but their values are also arrays, which have the extra-meta's ID as their sub-key, and
+	 * finally the extra meta's value as each sub-value. (eg
+	 * array('foo'=>array(1=>'bar',2=>'bill'),'monkey'=>array(3=>123)))
+	 *
+	 * @param boolean $one_of_each_key
+	 * @return array
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function all_extra_meta_array($one_of_each_key = true)
+	{
+		$return_array = array();
+		if ($one_of_each_key) {
+			$extra_meta_objs = $this->get_many_related(
+				'Extra_Meta',
+				array('group_by' => 'EXM_key')
+			);
+			foreach ($extra_meta_objs as $extra_meta_obj) {
+				if ($extra_meta_obj instanceof EE_Extra_Meta) {
+					$return_array[ $extra_meta_obj->key() ] = $extra_meta_obj->value();
+				}
+			}
+		} else {
+			$extra_meta_objs = $this->get_many_related('Extra_Meta');
+			foreach ($extra_meta_objs as $extra_meta_obj) {
+				if ($extra_meta_obj instanceof EE_Extra_Meta) {
+					if (! isset($return_array[ $extra_meta_obj->key() ])) {
+						$return_array[ $extra_meta_obj->key() ] = array();
+					}
+					$return_array[ $extra_meta_obj->key() ][ $extra_meta_obj->ID() ] = $extra_meta_obj->value();
+				}
+			}
+		}
+		return $return_array;
+	}
+
+
+	/**
+	 * Gets a pretty nice displayable nice for this model object. Often overridden
+	 *
+	 * @return string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function name()
+	{
+		// find a field that's not a text field
+		$field_we_can_use = $this->get_model()->get_a_field_of_type('EE_Text_Field_Base');
+		if ($field_we_can_use) {
+			return $this->get($field_we_can_use->get_name());
+		}
+		$first_few_properties = $this->model_field_array();
+		$first_few_properties = array_slice($first_few_properties, 0, 3);
+		$name_parts = array();
+		foreach ($first_few_properties as $name => $value) {
+			$name_parts[] = "$name:$value";
+		}
+		return implode(',', $name_parts);
+	}
+
+
+	/**
+	 * in_entity_map
+	 * Checks if this model object has been proven to already be in the entity map
+	 *
+	 * @return boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function in_entity_map()
+	{
+		// well, if we looked, did we find it in the entity map?
+		return $this->ID() && $this->get_model()->get_from_entity_map($this->ID()) === $this;
+	}
+
+
+	/**
+	 * refresh_from_db
+	 * Makes sure the fields and values on this model object are in-sync with what's in the database.
+	 *
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error if this model object isn't in the entity mapper (because then you should
+	 * just use what's in the entity mapper and refresh it) and WP_DEBUG is TRUE
+	 */
+	public function refresh_from_db()
+	{
+		if ($this->ID() && $this->in_entity_map()) {
+			$this->get_model()->refresh_entity_map_from_db($this->ID());
+		} else {
+			// if it doesn't have ID, you shouldn't be asking to refresh it from teh database (because its not in the database)
+			// if it has an ID but it's not in the map, and you're asking me to refresh it
+			// that's kinda dangerous. You should just use what's in the entity map, or add this to the entity map if there's
+			// absolutely nothing in it for this ID
+			if (WP_DEBUG) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Trying to refresh a model object with ID "%1$s" that\'s not in the entity map? First off: you should put it in the entity map by calling %2$s. Second off, if you want what\'s in the database right now, you should just call %3$s yourself and discard this model object.',
+							'event_espresso'
+						),
+						$this->ID(),
+						get_class($this->get_model()) . '::instance()->add_to_entity_map()',
+						get_class($this->get_model()) . '::instance()->refresh_entity_map()'
+					)
+				);
+			}
+		}
+	}
+
+
+	/**
+	 * Change $fields' values to $new_value_sql (which is a string of raw SQL)
+	 *
+	 * @since $VID:$
+	 * @param EE_Model_Field_Base[] $fields
+	 * @param string $new_value_sql
+	 *      example: 'column_name=123',
+	 *      or 'column_name=column_name+1',
+	 *      or 'column_name= CASE
+	 *          WHEN (`column_name` + `other_column` + 5) <= `yet_another_column`
+	 *          THEN `column_name` + 5
+	 *          ELSE `column_name`
+	 *      END'
+	 *      Also updates $field on this model object with the latest value from the database.
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function updateFieldsInDB($fields, $new_value_sql)
+	{
+		// First make sure this model object actually exists in the DB. It would be silly to try to update it in the DB
+		// if it wasn't even there to start off.
+		if (! $this->ID()) {
+			$this->save();
+		}
+		global $wpdb;
+		if (empty($fields)) {
+			throw new InvalidArgumentException(
+				esc_html__(
+					'EE_Base_Class::updateFieldsInDB was passed an empty array of fields.',
+					'event_espresso'
+				)
+			);
+		}
+		$first_field = reset($fields);
+		$table_alias = $first_field->get_table_alias();
+		foreach ($fields as $field) {
+			if ($table_alias !== $field->get_table_alias()) {
+				throw new InvalidArgumentException(
+					sprintf(
+						esc_html__(
+							// @codingStandardsIgnoreStart
+							'EE_Base_Class::updateFieldsInDB was passed fields for different tables ("%1$s" and "%2$s"), which is not supported. Instead, please call the method multiple times.',
+							// @codingStandardsIgnoreEnd
+							'event_espresso'
+						),
+						$table_alias,
+						$field->get_table_alias()
+					)
+				);
+			}
+		}
+		// Ok the fields are now known to all be for the same table. Proceed with creating the SQL to update it.
+		$table_obj = $this->get_model()->get_table_obj_by_alias($table_alias);
+		$table_pk_value = $this->ID();
+		$table_name = $table_obj->get_table_name();
+		if ($table_obj instanceof EE_Secondary_Table) {
+			$table_pk_field_name = $table_obj->get_fk_on_table();
+		} else {
+			$table_pk_field_name = $table_obj->get_pk_column();
+		}
+
+		$query =
+			"UPDATE `{$table_name}`
             SET "
-            . $new_value_sql
-            . $wpdb->prepare(
-                "
+			. $new_value_sql
+			. $wpdb->prepare(
+				"
             WHERE `{$table_pk_field_name}` = %d;",
-                $table_pk_value
-            );
-        $result = $wpdb->query($query);
-        foreach ($fields as $field) {
-            // If it was successful, we'd like to know the new value.
-            // If it failed, we'd also like to know the new value.
-            $new_value = $this->get_model()->get_var(
-                $this->get_model()->alter_query_params_to_restrict_by_ID(
-                    $this->get_model()->get_index_primary_key_string(
-                        $this->model_field_array()
-                    ),
-                    array(
-                        'default_where_conditions' => 'minimum',
-                    )
-                ),
-                $field->get_name()
-            );
-            $this->set_from_db(
-                $field->get_name(),
-                $new_value
-            );
-        }
-        return (bool) $result;
-    }
-
-
-    /**
-     * Nudges $field_name's value by $quantity, without any conditionals (in comparison to bumpConditionally()).
-     * Does not allow negative values, however.
-     *
-     * @since $VID:$
-     * @param array $fields_n_quantities keys are the field names, and values are the amount by which to bump them
-     *                                   (positive or negative). One important gotcha: all these values must be
-     *                                   on the same table (eg don't pass in one field for the posts table and
-     *                                   another for the event meta table.)
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function adjustNumericFieldsInDb(array $fields_n_quantities)
-    {
-        global $wpdb;
-        if (empty($fields_n_quantities)) {
-            // No fields to update? Well sure, we updated them to that value just fine.
-            return true;
-        }
-        $fields = [];
-        $set_sql_statements = [];
-        foreach ($fields_n_quantities as $field_name => $quantity) {
-            $field = $this->get_model()->field_settings_for($field_name, true);
-            $fields[] = $field;
-            $column_name = $field->get_table_column();
-
-            $abs_qty = absint($quantity);
-            if ($quantity > 0) {
-                // don't let the value be negative as often these fields are unsigned
-                $set_sql_statements[] = $wpdb->prepare(
-                    "`{$column_name}` = `{$column_name}` + %d",
-                    $abs_qty
-                );
-            } else {
-                $set_sql_statements[] = $wpdb->prepare(
-                    "`{$column_name}` = CASE
+				$table_pk_value
+			);
+		$result = $wpdb->query($query);
+		foreach ($fields as $field) {
+			// If it was successful, we'd like to know the new value.
+			// If it failed, we'd also like to know the new value.
+			$new_value = $this->get_model()->get_var(
+				$this->get_model()->alter_query_params_to_restrict_by_ID(
+					$this->get_model()->get_index_primary_key_string(
+						$this->model_field_array()
+					),
+					array(
+						'default_where_conditions' => 'minimum',
+					)
+				),
+				$field->get_name()
+			);
+			$this->set_from_db(
+				$field->get_name(),
+				$new_value
+			);
+		}
+		return (bool) $result;
+	}
+
+
+	/**
+	 * Nudges $field_name's value by $quantity, without any conditionals (in comparison to bumpConditionally()).
+	 * Does not allow negative values, however.
+	 *
+	 * @since $VID:$
+	 * @param array $fields_n_quantities keys are the field names, and values are the amount by which to bump them
+	 *                                   (positive or negative). One important gotcha: all these values must be
+	 *                                   on the same table (eg don't pass in one field for the posts table and
+	 *                                   another for the event meta table.)
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function adjustNumericFieldsInDb(array $fields_n_quantities)
+	{
+		global $wpdb;
+		if (empty($fields_n_quantities)) {
+			// No fields to update? Well sure, we updated them to that value just fine.
+			return true;
+		}
+		$fields = [];
+		$set_sql_statements = [];
+		foreach ($fields_n_quantities as $field_name => $quantity) {
+			$field = $this->get_model()->field_settings_for($field_name, true);
+			$fields[] = $field;
+			$column_name = $field->get_table_column();
+
+			$abs_qty = absint($quantity);
+			if ($quantity > 0) {
+				// don't let the value be negative as often these fields are unsigned
+				$set_sql_statements[] = $wpdb->prepare(
+					"`{$column_name}` = `{$column_name}` + %d",
+					$abs_qty
+				);
+			} else {
+				$set_sql_statements[] = $wpdb->prepare(
+					"`{$column_name}` = CASE
                        WHEN (`{$column_name}` >= %d)
                        THEN `{$column_name}` - %d
                        ELSE 0
                     END",
-                    $abs_qty,
-                    $abs_qty
-                );
-            }
-        }
-        return $this->updateFieldsInDB(
-            $fields,
-            implode(', ', $set_sql_statements)
-        );
-    }
-
-
-    /**
-     * Increases the value of the field $field_name_to_bump by $quantity, but only if the values of
-     * $field_name_to_bump plus $field_name_affecting_total and $quantity won't exceed $limit_field_name's value.
-     * For example, this is useful when bumping the value of TKT_reserved, TKT_sold, DTT_reserved or DTT_sold.
-     * Returns true if the value was successfully bumped, and updates the value on this model object.
-     * Otherwise returns false.
-     *
-     * @since $VID:$
-     * @param string $field_name_to_bump
-     * @param string $field_name_affecting_total
-     * @param string $limit_field_name
-     * @param int    $quantity
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function incrementFieldConditionallyInDb($field_name_to_bump, $field_name_affecting_total, $limit_field_name, $quantity)
-    {
-        global $wpdb;
-        $field = $this->get_model()->field_settings_for($field_name_to_bump, true);
-        $column_name = $field->get_table_column();
-
-        $field_affecting_total = $this->get_model()->field_settings_for($field_name_affecting_total, true);
-        $column_affecting_total = $field_affecting_total->get_table_column();
-
-        $limiting_field = $this->get_model()->field_settings_for($limit_field_name, true);
-        $limiting_column = $limiting_field->get_table_column();
-        return $this->updateFieldsInDB(
-            [$field],
-            $wpdb->prepare(
-                "`{$column_name}` =
+					$abs_qty,
+					$abs_qty
+				);
+			}
+		}
+		return $this->updateFieldsInDB(
+			$fields,
+			implode(', ', $set_sql_statements)
+		);
+	}
+
+
+	/**
+	 * Increases the value of the field $field_name_to_bump by $quantity, but only if the values of
+	 * $field_name_to_bump plus $field_name_affecting_total and $quantity won't exceed $limit_field_name's value.
+	 * For example, this is useful when bumping the value of TKT_reserved, TKT_sold, DTT_reserved or DTT_sold.
+	 * Returns true if the value was successfully bumped, and updates the value on this model object.
+	 * Otherwise returns false.
+	 *
+	 * @since $VID:$
+	 * @param string $field_name_to_bump
+	 * @param string $field_name_affecting_total
+	 * @param string $limit_field_name
+	 * @param int    $quantity
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function incrementFieldConditionallyInDb($field_name_to_bump, $field_name_affecting_total, $limit_field_name, $quantity)
+	{
+		global $wpdb;
+		$field = $this->get_model()->field_settings_for($field_name_to_bump, true);
+		$column_name = $field->get_table_column();
+
+		$field_affecting_total = $this->get_model()->field_settings_for($field_name_affecting_total, true);
+		$column_affecting_total = $field_affecting_total->get_table_column();
+
+		$limiting_field = $this->get_model()->field_settings_for($limit_field_name, true);
+		$limiting_column = $limiting_field->get_table_column();
+		return $this->updateFieldsInDB(
+			[$field],
+			$wpdb->prepare(
+				"`{$column_name}` =
             CASE
                WHEN ((`{$column_name}` + `{$column_affecting_total}` + %d) <= `{$limiting_column}`) OR `{$limiting_column}` = %d
                THEN `{$column_name}` + %d
                ELSE `{$column_name}`
             END",
-                $quantity,
-                EE_INF_IN_DB,
-                $quantity
-            )
-        );
-    }
-
-
-    /**
-     * Because some other plugins, like Advanced Cron Manager, expect all objects to have this method
-     * (probably a bad assumption they have made, oh well)
-     *
-     * @return string
-     */
-    public function __toString()
-    {
-        try {
-            return sprintf('%s (%s)', $this->name(), $this->ID());
-        } catch (Exception $e) {
-            EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
-            return '';
-        }
-    }
-
-
-    /**
-     * Clear related model objects if they're already in the DB, because otherwise when we
-     * UN-serialize this model object we'll need to be careful to add them to the entity map.
-     * This means if we have made changes to those related model objects, and want to unserialize
-     * the this model object on a subsequent request, changes to those related model objects will be lost.
-     * Instead, those related model objects should be directly serialized and stored.
-     * Eg, the following won't work:
-     * $reg = EEM_Registration::instance()->get_one_by_ID( 123 );
-     * $att = $reg->attendee();
-     * $att->set( 'ATT_fname', 'Dirk' );
-     * update_option( 'my_option', serialize( $reg ) );
-     * //END REQUEST
-     * //START NEXT REQUEST
-     * $reg = get_option( 'my_option' );
-     * $reg->attendee()->save();
-     * And would need to be replace with:
-     * $reg = EEM_Registration::instance()->get_one_by_ID( 123 );
-     * $att = $reg->attendee();
-     * $att->set( 'ATT_fname', 'Dirk' );
-     * update_option( 'my_option', serialize( $reg ) );
-     * //END REQUEST
-     * //START NEXT REQUEST
-     * $att = get_option( 'my_option' );
-     * $att->save();
-     *
-     * @return array
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function __sleep()
-    {
-        $model = $this->get_model();
-        foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                $classname = 'EE_' . $model->get_this_model_name();
-                if ($this->get_one_from_cache($relation_name) instanceof $classname
-                    && $this->get_one_from_cache($relation_name)->ID()
-                ) {
-                    $this->clear_cache(
-                        $relation_name,
-                        $this->get_one_from_cache($relation_name)->ID()
-                    );
-                }
-            }
-        }
-        $this->_props_n_values_provided_in_constructor = array();
-        $properties_to_serialize = get_object_vars($this);
-        // don't serialize the model. It's big and that risks recursion
-        unset($properties_to_serialize['_model']);
-        return array_keys($properties_to_serialize);
-    }
-
-
-    /**
-     * restore _props_n_values_provided_in_constructor
-     * PLZ NOTE: this will reset the array to whatever fields values were present prior to serialization,
-     * and therefore should NOT be used to determine if state change has occurred since initial construction.
-     * At best, you would only be able to detect if state change has occurred during THIS request.
-     */
-    public function __wakeup()
-    {
-        $this->_props_n_values_provided_in_constructor = $this->_fields;
-    }
-
-
-    /**
-     * Usage of this magic method is to ensure any internally cached references to object instances that must remain
-     * distinct with the clone host instance are also cloned.
-     */
-    public function __clone()
-    {
-        // handle DateTimes (this is handled in here because there's no one specific child class that uses datetimes).
-        foreach ($this->_fields as $field => $value) {
-            if ($value instanceof DateTime) {
-                $this->_fields[ $field ] = clone $value;
-            }
-        }
-    }
+				$quantity,
+				EE_INF_IN_DB,
+				$quantity
+			)
+		);
+	}
+
+
+	/**
+	 * Because some other plugins, like Advanced Cron Manager, expect all objects to have this method
+	 * (probably a bad assumption they have made, oh well)
+	 *
+	 * @return string
+	 */
+	public function __toString()
+	{
+		try {
+			return sprintf('%s (%s)', $this->name(), $this->ID());
+		} catch (Exception $e) {
+			EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
+			return '';
+		}
+	}
+
+
+	/**
+	 * Clear related model objects if they're already in the DB, because otherwise when we
+	 * UN-serialize this model object we'll need to be careful to add them to the entity map.
+	 * This means if we have made changes to those related model objects, and want to unserialize
+	 * the this model object on a subsequent request, changes to those related model objects will be lost.
+	 * Instead, those related model objects should be directly serialized and stored.
+	 * Eg, the following won't work:
+	 * $reg = EEM_Registration::instance()->get_one_by_ID( 123 );
+	 * $att = $reg->attendee();
+	 * $att->set( 'ATT_fname', 'Dirk' );
+	 * update_option( 'my_option', serialize( $reg ) );
+	 * //END REQUEST
+	 * //START NEXT REQUEST
+	 * $reg = get_option( 'my_option' );
+	 * $reg->attendee()->save();
+	 * And would need to be replace with:
+	 * $reg = EEM_Registration::instance()->get_one_by_ID( 123 );
+	 * $att = $reg->attendee();
+	 * $att->set( 'ATT_fname', 'Dirk' );
+	 * update_option( 'my_option', serialize( $reg ) );
+	 * //END REQUEST
+	 * //START NEXT REQUEST
+	 * $att = get_option( 'my_option' );
+	 * $att->save();
+	 *
+	 * @return array
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function __sleep()
+	{
+		$model = $this->get_model();
+		foreach ($model->relation_settings() as $relation_name => $relation_obj) {
+			if ($relation_obj instanceof EE_Belongs_To_Relation) {
+				$classname = 'EE_' . $model->get_this_model_name();
+				if ($this->get_one_from_cache($relation_name) instanceof $classname
+					&& $this->get_one_from_cache($relation_name)->ID()
+				) {
+					$this->clear_cache(
+						$relation_name,
+						$this->get_one_from_cache($relation_name)->ID()
+					);
+				}
+			}
+		}
+		$this->_props_n_values_provided_in_constructor = array();
+		$properties_to_serialize = get_object_vars($this);
+		// don't serialize the model. It's big and that risks recursion
+		unset($properties_to_serialize['_model']);
+		return array_keys($properties_to_serialize);
+	}
+
+
+	/**
+	 * restore _props_n_values_provided_in_constructor
+	 * PLZ NOTE: this will reset the array to whatever fields values were present prior to serialization,
+	 * and therefore should NOT be used to determine if state change has occurred since initial construction.
+	 * At best, you would only be able to detect if state change has occurred during THIS request.
+	 */
+	public function __wakeup()
+	{
+		$this->_props_n_values_provided_in_constructor = $this->_fields;
+	}
+
+
+	/**
+	 * Usage of this magic method is to ensure any internally cached references to object instances that must remain
+	 * distinct with the clone host instance are also cloned.
+	 */
+	public function __clone()
+	{
+		// handle DateTimes (this is handled in here because there's no one specific child class that uses datetimes).
+		foreach ($this->_fields as $field => $value) {
+			if ($value instanceof DateTime) {
+				$this->_fields[ $field ] = clone $value;
+			}
+		}
+	}
 }

core/db_classes/EE_Ticket.class.php

Indentation +1723 added lines, -1723 removed lines

@@ -14,1731 +14,1731 @@
 class EE_Ticket extends EE_Soft_Delete_Base_Class implements EEI_Line_Item_Object, EEI_Event_Relation, EEI_Has_Icon
 {
 
-    /**
-     * The following constants are used by the ticket_status() method to indicate whether a ticket is on sale or not.
-     */
-    const sold_out = 'TKS';
-
-    /**
-     *
-     */
-    const expired = 'TKE';
-
-    /**
-     *
-     */
-    const archived = 'TKA';
-
-    /**
-     *
-     */
-    const pending = 'TKP';
-
-    /**
-     *
-     */
-    const onsale = 'TKO';
-
-    /**
-     * extra meta key for tracking ticket reservations
-     *
-     * @type string
-     */
-    const META_KEY_TICKET_RESERVATIONS = 'ticket_reservations';
-
-    /**
-     * cached result from method of the same name
-     *
-     * @var float $_ticket_total_with_taxes
-     */
-    private $_ticket_total_with_taxes;
-
-
-    /**
-     * @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  $date_formats            incoming date_formats in an array where the first value is the
-     *                                        date_format and the second value is the time format
-     * @return EE_Ticket
-     * @throws EE_Error
-     */
-    public static function new_instance($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, $date_formats);
-    }
-
-
-    /**
-     * @param array  $props_n_values  incoming values from the database
-     * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
-     *                                the website will be used.
-     * @return EE_Ticket
-     * @throws EE_Error
-     */
-    public static function new_instance_from_db($props_n_values = array(), $timezone = null)
-    {
-        return new self($props_n_values, true, $timezone);
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     */
-    public function parent()
-    {
-        return $this->get('TKT_parent');
-    }
-
-
-    /**
-     * return if a ticket has quantities available for purchase
-     *
-     * @param  int $DTT_ID the primary key for a particular datetime
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function available($DTT_ID = 0)
-    {
-        // are we checking availability for a particular datetime ?
-        if ($DTT_ID) {
-            // get that datetime object
-            $datetime = $this->get_first_related('Datetime', array(array('DTT_ID' => $DTT_ID)));
-            // if  ticket sales for this datetime have exceeded the reg limit...
-            if ($datetime instanceof EE_Datetime && $datetime->sold_out()) {
-                return false;
-            }
-        }
-        // datetime is still open for registration, but is this ticket sold out ?
-        return $this->qty() < 1 || $this->qty() > $this->sold() ? true : false;
-    }
-
-
-    /**
-     * Using the start date and end date this method calculates whether the ticket is On Sale, Pending, or Expired
-     *
-     * @param bool        $display   true = we'll return a localized string, otherwise we just return the value of the
-     *                               relevant status const
-     * @param bool | null $remaining if it is already known that tickets are available, then simply pass a bool to save
-     *               further processing
-     * @return mixed status int if the display string isn't requested
-     * @throws EE_Error
-     */
-    public function ticket_status($display = false, $remaining = null)
-    {
-        $remaining = is_bool($remaining) ? $remaining : $this->is_remaining();
-        if (! $remaining) {
-            return $display ? EEH_Template::pretty_status(EE_Ticket::sold_out, false, 'sentence') : EE_Ticket::sold_out;
-        }
-        if ($this->get('TKT_deleted')) {
-            return $display ? EEH_Template::pretty_status(EE_Ticket::archived, false, 'sentence') : EE_Ticket::archived;
-        }
-        if ($this->is_expired()) {
-            return $display ? EEH_Template::pretty_status(EE_Ticket::expired, false, 'sentence') : EE_Ticket::expired;
-        }
-        if ($this->is_pending()) {
-            return $display ? EEH_Template::pretty_status(EE_Ticket::pending, false, 'sentence') : EE_Ticket::pending;
-        }
-        if ($this->is_on_sale()) {
-            return $display ? EEH_Template::pretty_status(EE_Ticket::onsale, false, 'sentence') : EE_Ticket::onsale;
-        }
-        return '';
-    }
-
-
-    /**
-     * The purpose of this method is to simply return a boolean for whether there are any tickets remaining for sale
-     * considering ALL the factors used for figuring that out.
-     *
-     * @access public
-     * @param  int $DTT_ID if an int above 0 is included here then we get a specific dtt.
-     * @return boolean         true = tickets remaining, false not.
-     * @throws EE_Error
-     */
-    public function is_remaining($DTT_ID = 0)
-    {
-        $num_remaining = $this->remaining($DTT_ID);
-        if ($num_remaining === 0) {
-            return false;
-        }
-        if ($num_remaining > 0 && $num_remaining < $this->min()) {
-            return false;
-        }
-        return true;
-    }
-
-
-    /**
-     * return the total number of tickets available for purchase
-     *
-     * @param  int $DTT_ID the primary key for a particular datetime.
-     *                     set to 0 for all related datetimes
-     * @return int
-     * @throws EE_Error
-     */
-    public function remaining($DTT_ID = 0)
-    {
-        return $this->real_quantity_on_ticket('saleable', $DTT_ID);
-    }
-
-
-    /**
-     * Gets min
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function min()
-    {
-        return $this->get('TKT_min');
-    }
-
-
-    /**
-     * return if a ticket is no longer available cause its available dates have expired.
-     *
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function is_expired()
-    {
-        return ($this->get_raw('TKT_end_date') < time());
-    }
-
-
-    /**
-     * Return if a ticket is yet to go on sale or not
-     *
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function is_pending()
-    {
-        return ($this->get_raw('TKT_start_date') > time());
-    }
-
-
-    /**
-     * Return if a ticket is on sale or not
-     *
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function is_on_sale()
-    {
-        return ($this->get_raw('TKT_start_date') < time() && $this->get_raw('TKT_end_date') > time());
-    }
-
-
-    /**
-     * This returns the chronologically last datetime that this ticket is associated with
-     *
-     * @param string $dt_frmt
-     * @param string $conjunction - conjunction junction what's your function ? this string joins the start date with
-     *                            the end date ie: Jan 01 "to" Dec 31
-     * @return string
-     * @throws EE_Error
-     */
-    public function date_range($dt_frmt = '', $conjunction = ' - ')
-    {
-        $first_date = $this->first_datetime() instanceof EE_Datetime ? $this->first_datetime()->start_date($dt_frmt)
-            : '';
-        $last_date = $this->last_datetime() instanceof EE_Datetime ? $this->last_datetime()->end_date($dt_frmt) : '';
-
-        return $first_date && $last_date ? $first_date . $conjunction . $last_date : '';
-    }
-
-
-    /**
-     * This returns the chronologically first datetime that this ticket is associated with
-     *
-     * @return EE_Datetime
-     * @throws EE_Error
-     */
-    public function first_datetime()
-    {
-        $datetimes = $this->datetimes(array('limit' => 1));
-        return reset($datetimes);
-    }
-
-
-    /**
-     * Gets all the datetimes this ticket can be used for attending.
-     * Unless otherwise specified, orders datetimes by start date.
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Datetime[]|EE_Base_Class[]
-     * @throws EE_Error
-     */
-    public function datetimes($query_params = array())
-    {
-        if (! isset($query_params['order_by'])) {
-            $query_params['order_by']['DTT_order'] = 'ASC';
-        }
-        return $this->get_many_related('Datetime', $query_params);
-    }
-
-
-    /**
-     * This returns the chronologically last datetime that this ticket is associated with
-     *
-     * @return EE_Datetime
-     * @throws EE_Error
-     */
-    public function last_datetime()
-    {
-        $datetimes = $this->datetimes(array('limit' => 1, 'order_by' => array('DTT_EVT_start' => 'DESC')));
-        return end($datetimes);
-    }
-
-
-    /**
-     * This returns the total tickets sold depending on the given parameters.
-     *
-     * @param  string $what   Can be one of two options: 'ticket', 'datetime'.
-     *                        'ticket' = total ticket sales for all datetimes this ticket is related to
-     *                        'datetime' = total ticket sales for a specified datetime (required $dtt_id)
-     *                        'datetime' = total ticket sales in the datetime_ticket table.
-     *                        If $dtt_id is not given then we return an array of sales indexed by datetime.
-     *                        If $dtt_id IS given then we return the tickets sold for that given datetime.
-     * @param  int    $dtt_id [optional] include the dtt_id with $what = 'datetime'.
-     * @return mixed (array|int)          how many tickets have sold
-     * @throws EE_Error
-     */
-    public function tickets_sold($what = 'ticket', $dtt_id = null)
-    {
-        $total = 0;
-        $tickets_sold = $this->_all_tickets_sold();
-        switch ($what) {
-            case 'ticket':
-                return $tickets_sold['ticket'];
-                break;
-            case 'datetime':
-                if (empty($tickets_sold['datetime'])) {
-                    return $total;
-                }
-                if (! empty($dtt_id) && ! isset($tickets_sold['datetime'][ $dtt_id ])) {
-                    EE_Error::add_error(
-                        __(
-                            'You\'ve requested the amount of tickets sold for a given ticket and datetime, however there are no records for the datetime id you included.  Are you SURE that is a datetime related to this ticket?',
-                            'event_espresso'
-                        ),
-                        __FILE__,
-                        __FUNCTION__,
-                        __LINE__
-                    );
-                    return $total;
-                }
-                return empty($dtt_id) ? $tickets_sold['datetime'] : $tickets_sold['datetime'][ $dtt_id ];
-                break;
-            default:
-                return $total;
-        }
-    }
-
-
-    /**
-     * This returns an array indexed by datetime_id for tickets sold with this ticket.
-     *
-     * @return EE_Ticket[]
-     * @throws EE_Error
-     */
-    protected function _all_tickets_sold()
-    {
-        $datetimes = $this->get_many_related('Datetime');
-        $tickets_sold = array();
-        if (! empty($datetimes)) {
-            foreach ($datetimes as $datetime) {
-                $tickets_sold['datetime'][ $datetime->ID() ] = $datetime->get('DTT_sold');
-            }
-        }
-        // Tickets sold
-        $tickets_sold['ticket'] = $this->sold();
-        return $tickets_sold;
-    }
-
-
-    /**
-     * This returns the base price object for the ticket.
-     *
-     * @param  bool $return_array whether to return as an array indexed by price id or just the object.
-     * @return EE_Price|EE_Base_Class|EE_Price[]|EE_Base_Class[]
-     * @throws EE_Error
-     */
-    public function base_price($return_array = false)
-    {
-        $_where = array('Price_Type.PBT_ID' => EEM_Price_Type::base_type_base_price);
-        return $return_array
-            ? $this->get_many_related('Price', array($_where))
-            : $this->get_first_related('Price', array($_where));
-    }
-
-
-    /**
-     * This returns ONLY the price modifiers for the ticket (i.e. no taxes or base price)
-     *
-     * @access public
-     * @return EE_Price[]
-     * @throws EE_Error
-     */
-    public function price_modifiers()
-    {
-        $query_params = array(
-            0 => array(
-                'Price_Type.PBT_ID' => array(
-                    'NOT IN',
-                    array(EEM_Price_Type::base_type_base_price, EEM_Price_Type::base_type_tax),
-                ),
-            ),
-        );
-        return $this->prices($query_params);
-    }
-
-
-    /**
-     * Gets all the prices that combine to form the final price of this ticket
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Price[]|EE_Base_Class[]
-     * @throws EE_Error
-     */
-    public function prices($query_params = array())
-    {
-        return $this->get_many_related('Price', $query_params);
-    }
-
-
-    /**
-     * Gets all the ticket applicabilities (ie, relations between datetimes and tickets)
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Datetime_Ticket|EE_Base_Class[]
-     * @throws EE_Error
-     */
-    public function datetime_tickets($query_params = array())
-    {
-        return $this->get_many_related('Datetime_Ticket', $query_params);
-    }
-
-
-    /**
-     * Gets all the datetimes from the db ordered by DTT_order
-     *
-     * @param boolean $show_expired
-     * @param boolean $show_deleted
-     * @return EE_Datetime[]
-     * @throws EE_Error
-     */
-    public function datetimes_ordered($show_expired = true, $show_deleted = false)
-    {
-        return EEM_Datetime::instance($this->_timezone)->get_datetimes_for_ticket_ordered_by_DTT_order(
-            $this->ID(),
-            $show_expired,
-            $show_deleted
-        );
-    }
-
-
-    /**
-     * Gets ID
-     *
-     * @return string
-     * @throws EE_Error
-     */
-    public function ID()
-    {
-        return $this->get('TKT_ID');
-    }
-
-
-    /**
-     * get the author of the ticket.
-     *
-     * @since 4.5.0
-     * @return int
-     * @throws EE_Error
-     */
-    public function wp_user()
-    {
-        return $this->get('TKT_wp_user');
-    }
-
-
-    /**
-     * Gets the template for the ticket
-     *
-     * @return EE_Ticket_Template|EE_Base_Class
-     * @throws EE_Error
-     */
-    public function template()
-    {
-        return $this->get_first_related('Ticket_Template');
-    }
-
-
-    /**
-     * Simply returns an array of EE_Price objects that are taxes.
-     *
-     * @return EE_Price[]
-     * @throws EE_Error
-     */
-    public function get_ticket_taxes_for_admin()
-    {
-        return EE_Taxes::get_taxes_for_admin();
-    }
-
-
-    /**
-     * @return float
-     * @throws EE_Error
-     */
-    public function ticket_price()
-    {
-        return $this->get('TKT_price');
-    }
-
-
-    /**
-     * @return mixed
-     * @throws EE_Error
-     */
-    public function pretty_price()
-    {
-        return $this->get_pretty('TKT_price');
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     */
-    public function is_free()
-    {
-        return $this->get_ticket_total_with_taxes() === (float) 0;
-    }
-
-
-    /**
-     * get_ticket_total_with_taxes
-     *
-     * @param bool $no_cache
-     * @return float
-     * @throws EE_Error
-     */
-    public function get_ticket_total_with_taxes($no_cache = false)
-    {
-        if ($this->_ticket_total_with_taxes === null || $no_cache) {
-            $this->_ticket_total_with_taxes = $this->get_ticket_subtotal() + $this->get_ticket_taxes_total_for_admin();
-        }
-        return (float) $this->_ticket_total_with_taxes;
-    }
-
-
-    public function ensure_TKT_Price_correct()
-    {
-        $this->set('TKT_price', EE_Taxes::get_subtotal_for_admin($this));
-        $this->save();
-    }
-
-
-    /**
-     * @return float
-     * @throws EE_Error
-     */
-    public function get_ticket_subtotal()
-    {
-        return EE_Taxes::get_subtotal_for_admin($this);
-    }
-
-
-    /**
-     * Returns the total taxes applied to this ticket
-     *
-     * @return float
-     * @throws EE_Error
-     */
-    public function get_ticket_taxes_total_for_admin()
-    {
-        return EE_Taxes::get_total_taxes_for_admin($this);
-    }
-
-
-    /**
-     * Sets name
-     *
-     * @param string $name
-     * @throws EE_Error
-     */
-    public function set_name($name)
-    {
-        $this->set('TKT_name', $name);
-    }
-
-
-    /**
-     * Gets description
-     *
-     * @return string
-     * @throws EE_Error
-     */
-    public function description()
-    {
-        return $this->get('TKT_description');
-    }
-
-
-    /**
-     * Sets description
-     *
-     * @param string $description
-     * @throws EE_Error
-     */
-    public function set_description($description)
-    {
-        $this->set('TKT_description', $description);
-    }
-
-
-    /**
-     * Gets start_date
-     *
-     * @param string $dt_frmt
-     * @param string $tm_frmt
-     * @return string
-     * @throws EE_Error
-     */
-    public function start_date($dt_frmt = '', $tm_frmt = '')
-    {
-        return $this->_get_datetime('TKT_start_date', $dt_frmt, $tm_frmt);
-    }
-
-
-    /**
-     * Sets start_date
-     *
-     * @param string $start_date
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_start_date($start_date)
-    {
-        $this->_set_date_time('B', $start_date, 'TKT_start_date');
-    }
-
-
-    /**
-     * Gets end_date
-     *
-     * @param string $dt_frmt
-     * @param string $tm_frmt
-     * @return string
-     * @throws EE_Error
-     */
-    public function end_date($dt_frmt = '', $tm_frmt = '')
-    {
-        return $this->_get_datetime('TKT_end_date', $dt_frmt, $tm_frmt);
-    }
-
-
-    /**
-     * Sets end_date
-     *
-     * @param string $end_date
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_end_date($end_date)
-    {
-        $this->_set_date_time('B', $end_date, 'TKT_end_date');
-    }
-
-
-    /**
-     * Sets sell until time
-     *
-     * @since 4.5.0
-     * @param string $time a string representation of the sell until time (ex 9am or 7:30pm)
-     * @throws EE_Error
-     */
-    public function set_end_time($time)
-    {
-        $this->_set_time_for($time, 'TKT_end_date');
-    }
-
-
-    /**
-     * Sets min
-     *
-     * @param int $min
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_min($min)
-    {
-        $this->set('TKT_min', $min);
-    }
-
-
-    /**
-     * Gets max
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function max()
-    {
-        return $this->get('TKT_max');
-    }
-
-
-    /**
-     * Sets max
-     *
-     * @param int $max
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_max($max)
-    {
-        $this->set('TKT_max', $max);
-    }
-
-
-    /**
-     * Sets price
-     *
-     * @param float $price
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_price($price)
-    {
-        $this->set('TKT_price', $price);
-    }
-
-
-    /**
-     * Gets sold
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function sold()
-    {
-        return $this->get_raw('TKT_sold');
-    }
-
-
-    /**
-     * Sets sold
-     *
-     * @param int $sold
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_sold($sold)
-    {
-        // sold can not go below zero
-        $sold = max(0, $sold);
-        $this->set('TKT_sold', $sold);
-    }
-
-
-    /**
-     * Increments sold by amount passed by $qty AND decrements the reserved count on both this ticket and its
-     * associated datetimes.
-     *
-     * @since $VID:$
-     * @param int $qty
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function increaseSold($qty = 1)
-    {
-        $qty = absint($qty);
-        // increment sold and decrement reserved datetime quantities simultaneously
-        // don't worry about failures, because they must have already had a spot reserved
-        $this->increaseSoldForDatetimes($qty);
-        // Increment and decrement ticket quantities simultaneously
-        $success = $this->adjustNumericFieldsInDb(
-            [
-                'TKT_reserved' => $qty * -1,
-                'TKT_sold' => $qty
-            ]
-        );
-        do_action(
-            'AHEE__EE_Ticket__increase_sold',
-            $this,
-            $qty,
-            $this->sold(),
-            $success
-        );
-        return $success;
-    }
-
-    /**
-     * On each datetime related to this ticket, increases its sold count and decreases its reserved count by $qty.
-     *
-     * @since $VID:$
-     * @param int $qty positive or negative. Positive means to increase sold counts (and decrease reserved counts),
-     *             Negative means to decreases old counts (and increase reserved counts).
-     * @param EE_Datetime[] $datetimes
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function increaseSoldForDatetimes($qty, array $datetimes = [])
-    {
-        $datetimes = ! empty($datetimes) ? $datetimes : $this->datetimes();
-        foreach ($datetimes as $datetime) {
-            $datetime->increaseSold($qty);
-        }
-    }
-
-
-
-    /**
-     * Decrements (subtracts) sold by amount passed by $qty on both the ticket and its related datetimes directly in the
-     * DB and then updates the model objects.
-     * Does not affect the reserved counts.
-     *
-     * @since $VID:$
-     * @param int $qty
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function decreaseSold($qty = 1)
-    {
-        $qty = absint($qty);
-        $this->decreaseSoldForDatetimes($qty);
-        $success = $this->adjustNumericFieldsInDb(
-            [
-                'TKT_sold' => $qty * -1
-            ]
-        );
-        do_action(
-            'AHEE__EE_Ticket__decrease_sold',
-            $this,
-            $qty,
-            $this->sold(),
-            $success
-        );
-        return $success;
-    }
-
-
-    /**
-     * Decreases sold on related datetimes
-     *
-     * @since $VID:$
-     * @param int $qty
-     * @param EE_Datetime[] $datetimes
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function decreaseSoldForDatetimes($qty = 1, array $datetimes = [])
-    {
-        $datetimes = ! empty($datetimes) ? $datetimes : $this->datetimes();
-        if (is_array($datetimes)) {
-            foreach ($datetimes as $datetime) {
-                if ($datetime instanceof EE_Datetime) {
-                    $datetime->decreaseSold($qty);
-                }
-            }
-        }
-    }
-
-
-    /**
-     * Gets qty of reserved tickets
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function reserved()
-    {
-        return $this->get_raw('TKT_reserved');
-    }
-
-
-    /**
-     * Sets reserved
-     *
-     * @param int $reserved
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_reserved($reserved)
-    {
-        // reserved can not go below zero
-        $reserved = max(0, (int) $reserved);
-        $this->set('TKT_reserved', $reserved);
-    }
-
-
-    /**
-     * Increments reserved by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @since $VID:$
-     * @param int    $qty
-     * @param string $source
-     * @return bool whether we successfully reserved the ticket or not.
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function increaseReserved($qty = 1, $source = 'unknown')
-    {
-        $qty = absint($qty);
-        do_action(
-            'AHEE__EE_Ticket__increase_reserved__begin',
-            $this,
-            $qty,
-            $source
-        );
-        $this->add_extra_meta(EE_Ticket::META_KEY_TICKET_RESERVATIONS, "{$qty} from {$source}");
-        $success = false;
-        $datetimes_adjusted_successfully = $this->increaseReservedForDatetimes($qty);
-        if ($datetimes_adjusted_successfully) {
-            $success = $this->incrementFieldConditionallyInDb(
-                'TKT_reserved',
-                'TKT_sold',
-                'TKT_qty',
-                $qty
-            );
-            if (! $success) {
-                // The datetimes were successfully bumped, but not the
-                // ticket. So we need to manually rollback the datetimes.
-                $this->decreaseReservedForDatetimes($qty);
-            }
-        }
-        do_action(
-            'AHEE__EE_Ticket__increase_reserved',
-            $this,
-            $qty,
-            $this->reserved(),
-            $success
-        );
-        return $success;
-    }
-
-
-    /**
-     * Increases reserved counts on related datetimes
-     *
-     * @since $VID:$
-     * @param int $qty
-     * @param EE_Datetime[] $datetimes
-     * @return boolean indicating success
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function increaseReservedForDatetimes($qty = 1, array $datetimes = [])
-    {
-        $datetimes = ! empty($datetimes) ? $datetimes : $this->datetimes();
-        $datetimes_updated = [];
-        $limit_exceeded = false;
-        if (is_array($datetimes)) {
-            foreach ($datetimes as $datetime) {
-                if ($datetime instanceof EE_Datetime) {
-                    if ($datetime->increaseReserved($qty)) {
-                        $datetimes_updated[] = $datetime;
-                    } else {
-                        $limit_exceeded = true;
-                        break;
-                    }
-                }
-            }
-            // If somewhere along the way we detected a datetime whose
-            // limit was exceeded, do a manual rollback.
-            if ($limit_exceeded) {
-                $this->decreaseReservedForDatetimes($qty, $datetimes_updated);
-                return false;
-            }
-        }
-        return true;
-    }
-
-
-    /**
-     * Decrements (subtracts) reserved by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @since $VID:$
-     * @param int    $qty
-     * @param bool   $adjust_datetimes
-     * @param string $source
-     * @return boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function decreaseReserved($qty = 1, $adjust_datetimes = true, $source = 'unknown')
-    {
-        $qty = absint($qty);
-        $this->add_extra_meta(EE_Ticket::META_KEY_TICKET_RESERVATIONS, "-{$qty} from {$source}");
-        if ($adjust_datetimes) {
-            $this->decreaseReservedForDatetimes($qty);
-        }
-        $success = $this->adjustNumericFieldsInDb(
-            [
-                'TKT_reserved' => $qty * -1
-            ]
-        );
-        do_action(
-            'AHEE__EE_Ticket__decrease_reserved',
-            $this,
-            $qty,
-            $this->reserved(),
-            $success
-        );
-        return $success;
-    }
-
-
-    /**
-     * Decreases the reserved count on the specified datetimes.
-     *
-     * @since $VID:$
-     * @param int           $qty
-     * @param EE_Datetime[] $datetimes
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function decreaseReservedForDatetimes($qty = 1, array $datetimes = [])
-    {
-        $datetimes = ! empty($datetimes) ? $datetimes : $this->datetimes();
-        foreach ($datetimes as $datetime) {
-            if ($datetime instanceof EE_Datetime) {
-                $datetime->decreaseReserved($qty);
-            }
-        }
-    }
-
-
-    /**
-     * Gets ticket quantity
-     *
-     * @param string $context     ticket quantity is somewhat subjective depending on the exact information sought
-     *                            therefore $context can be one of three values: '', 'reg_limit', or 'saleable'
-     *                            '' (default) quantity is the actual db value for TKT_qty, unaffected by other objects
-     *                            REG LIMIT: caps qty based on DTT_reg_limit for ALL related datetimes
-     *                            SALEABLE: also considers datetime sold and returns zero if ANY DTT is sold out, and
-     *                            is therefore the truest measure of tickets that can be purchased at the moment
-     * @return int
-     * @throws EE_Error
-     */
-    public function qty($context = '')
-    {
-        switch ($context) {
-            case 'reg_limit':
-                return $this->real_quantity_on_ticket();
-            case 'saleable':
-                return $this->real_quantity_on_ticket('saleable');
-            default:
-                return $this->get_raw('TKT_qty');
-        }
-    }
-
-
-    /**
-     * Gets ticket quantity
-     *
-     * @param string $context     ticket quantity is somewhat subjective depending on the exact information sought
-     *                            therefore $context can be one of two values: 'reg_limit', or 'saleable'
-     *                            REG LIMIT: caps qty based on DTT_reg_limit for ALL related datetimes
-     *                            SALEABLE: also considers datetime sold and returns zero if ANY DTT is sold out, and
-     *                            is therefore the truest measure of tickets that can be purchased at the moment
-     * @param  int   $DTT_ID      the primary key for a particular datetime.
-     *                            set to 0 for all related datetimes
-     * @return int
-     * @throws EE_Error
-     */
-    public function real_quantity_on_ticket($context = 'reg_limit', $DTT_ID = 0)
-    {
-        $raw = $this->get_raw('TKT_qty');
-        // return immediately if it's zero
-        if ($raw === 0) {
-            return $raw;
-        }
-        // echo "\n\n<br />Ticket: " . $this->name() . '<br />';
-        // ensure qty doesn't exceed raw value for THIS ticket
-        $qty = min(EE_INF, $raw);
-        // echo "\n . qty: " . $qty . '<br />';
-        // calculate this ticket's total sales and reservations
-        $sold_and_reserved_for_this_ticket = $this->sold() + $this->reserved();
-        // echo "\n . sold: " . $this->sold() . '<br />';
-        // echo "\n . reserved: " . $this->reserved() . '<br />';
-        // echo "\n . sold_and_reserved_for_this_ticket: " . $sold_and_reserved_for_this_ticket . '<br />';
-        // first we need to calculate the maximum number of tickets available for the datetime
-        // do we want data for one datetime or all of them ?
-        $query_params = $DTT_ID ? array(array('DTT_ID' => $DTT_ID)) : array();
-        $datetimes = $this->datetimes($query_params);
-        if (is_array($datetimes) && ! empty($datetimes)) {
-            foreach ($datetimes as $datetime) {
-                if ($datetime instanceof EE_Datetime) {
-                    $datetime->refresh_from_db();
-                    // echo "\n . . datetime name: " . $datetime->name() . '<br />';
-                    // echo "\n . . datetime ID: " . $datetime->ID() . '<br />';
-                    // initialize with no restrictions for each datetime
-                    // but adjust datetime qty based on datetime reg limit
-                    $datetime_qty = min(EE_INF, $datetime->reg_limit());
-                    // echo "\n . . . datetime reg_limit: " . $datetime->reg_limit() . '<br />';
-                    // echo "\n . . . datetime_qty: " . $datetime_qty . '<br />';
-                    // if we want the actual saleable amount, then we need to consider OTHER ticket sales
-                    // and reservations for this datetime, that do NOT include sales and reservations
-                    // for this ticket (so we add $this->sold() and $this->reserved() back in)
-                    if ($context === 'saleable') {
-                        $datetime_qty = max(
-                            $datetime_qty - $datetime->sold_and_reserved() + $sold_and_reserved_for_this_ticket,
-                            0
-                        );
-                        // echo "\n . . . datetime sold: " . $datetime->sold() . '<br />';
-                        // echo "\n . . . datetime reserved: " . $datetime->reserved() . '<br />';
-                        // echo "\n . . . datetime sold_and_reserved: " . $datetime->sold_and_reserved() . '<br />';
-                        // echo "\n . . . datetime_qty: " . $datetime_qty . '<br />';
-                        $datetime_qty = ! $datetime->sold_out() ? $datetime_qty : 0;
-                        // echo "\n . . . datetime_qty: " . $datetime_qty . '<br />';
-                    }
-                    $qty = min($datetime_qty, $qty);
-                    // echo "\n . . qty: " . $qty . '<br />';
-                }
-            }
-        }
-        // NOW that we know the  maximum number of tickets available for the datetime
-        // we can finally factor in the details for this specific ticket
-        if ($qty > 0 && $context === 'saleable') {
-            // and subtract the sales for THIS ticket
-            $qty = max($qty - $sold_and_reserved_for_this_ticket, 0);
-            // echo "\n . qty: " . $qty . '<br />';
-        }
-        // echo "\nFINAL QTY: " . $qty . "<br /><br />";
-        return $qty;
-    }
-
-
-    /**
-     * Sets qty - IMPORTANT!!! Does NOT allow QTY to be set higher than the lowest reg limit of any related datetimes
-     *
-     * @param int $qty
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_qty($qty)
-    {
-        $datetimes = $this->datetimes();
-        foreach ($datetimes as $datetime) {
-            if ($datetime instanceof EE_Datetime) {
-                $qty = min($qty, $datetime->reg_limit());
-            }
-        }
-        $this->set('TKT_qty', $qty);
-    }
-
-
-    /**
-     * Gets uses
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function uses()
-    {
-        return $this->get('TKT_uses');
-    }
-
-
-    /**
-     * Sets uses
-     *
-     * @param int $uses
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_uses($uses)
-    {
-        $this->set('TKT_uses', $uses);
-    }
-
-
-    /**
-     * returns whether ticket is required or not.
-     *
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function required()
-    {
-        return $this->get('TKT_required');
-    }
-
-
-    /**
-     * sets the TKT_required property
-     *
-     * @param boolean $required
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_required($required)
-    {
-        $this->set('TKT_required', $required);
-    }
-
-
-    /**
-     * Gets taxable
-     *
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function taxable()
-    {
-        return $this->get('TKT_taxable');
-    }
-
-
-    /**
-     * Sets taxable
-     *
-     * @param boolean $taxable
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_taxable($taxable)
-    {
-        $this->set('TKT_taxable', $taxable);
-    }
-
-
-    /**
-     * Gets is_default
-     *
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function is_default()
-    {
-        return $this->get('TKT_is_default');
-    }
-
-
-    /**
-     * Sets is_default
-     *
-     * @param boolean $is_default
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_is_default($is_default)
-    {
-        $this->set('TKT_is_default', $is_default);
-    }
-
-
-    /**
-     * Gets order
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function order()
-    {
-        return $this->get('TKT_order');
-    }
-
-
-    /**
-     * Sets order
-     *
-     * @param int $order
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_order($order)
-    {
-        $this->set('TKT_order', $order);
-    }
-
-
-    /**
-     * Gets row
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function row()
-    {
-        return $this->get('TKT_row');
-    }
-
-
-    /**
-     * Sets row
-     *
-     * @param int $row
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_row($row)
-    {
-        $this->set('TKT_row', $row);
-    }
-
-
-    /**
-     * Gets deleted
-     *
-     * @return boolean
-     * @throws EE_Error
-     */
-    public function deleted()
-    {
-        return $this->get('TKT_deleted');
-    }
-
-
-    /**
-     * Sets deleted
-     *
-     * @param boolean $deleted
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_deleted($deleted)
-    {
-        $this->set('TKT_deleted', $deleted);
-    }
-
-
-    /**
-     * Gets parent
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function parent_ID()
-    {
-        return $this->get('TKT_parent');
-    }
-
-
-    /**
-     * Sets parent
-     *
-     * @param int $parent
-     * @return void
-     * @throws EE_Error
-     */
-    public function set_parent_ID($parent)
-    {
-        $this->set('TKT_parent', $parent);
-    }
-
-
-    /**
-     * Gets a string which is handy for showing in gateways etc that describes the ticket.
-     *
-     * @return string
-     * @throws EE_Error
-     */
-    public function name_and_info()
-    {
-        $times = array();
-        foreach ($this->datetimes() as $datetime) {
-            $times[] = $datetime->start_date_and_time();
-        }
-        return $this->name() . ' @ ' . implode(', ', $times) . ' for ' . $this->pretty_price();
-    }
-
-
-    /**
-     * Gets name
-     *
-     * @return string
-     * @throws EE_Error
-     */
-    public function name()
-    {
-        return $this->get('TKT_name');
-    }
-
-
-    /**
-     * Gets price
-     *
-     * @return float
-     * @throws EE_Error
-     */
-    public function price()
-    {
-        return $this->get('TKT_price');
-    }
-
-
-    /**
-     * Gets all the registrations for this ticket
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Registration[]|EE_Base_Class[]
-     * @throws EE_Error
-     */
-    public function registrations($query_params = array())
-    {
-        return $this->get_many_related('Registration', $query_params);
-    }
-
-
-    /**
-     * Updates the TKT_sold attribute (and saves) based on the number of APPROVED registrations for this ticket.
-     *
-     * @return int
-     * @throws EE_Error
-     */
-    public function update_tickets_sold()
-    {
-        $count_regs_for_this_ticket = $this->count_registrations(
-            array(
-                array(
-                    'STS_ID'      => EEM_Registration::status_id_approved,
-                    'REG_deleted' => 0,
-                ),
-            )
-        );
-        $this->set_sold($count_regs_for_this_ticket);
-        $this->save();
-        return $count_regs_for_this_ticket;
-    }
-
-
-    /**
-     * Counts the registrations for this ticket
-     *
-     * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return int
-     */
-    public function count_registrations($query_params = array())
-    {
-        return $this->count_related('Registration', $query_params);
-    }
-
-
-    /**
-     * Implementation for EEI_Has_Icon interface method.
-     *
-     * @see EEI_Visual_Representation for comments
-     * @return string
-     */
-    public function get_icon()
-    {
-        return '<span class="dashicons dashicons-tickets-alt"></span>';
-    }
-
-
-    /**
-     * Implementation of the EEI_Event_Relation interface method
-     *
-     * @see EEI_Event_Relation for comments
-     * @return EE_Event
-     * @throws EE_Error
-     * @throws UnexpectedEntityException
-     */
-    public function get_related_event()
-    {
-        // get one datetime to use for getting the event
-        $datetime = $this->first_datetime();
-        if (! $datetime instanceof \EE_Datetime) {
-            throw new UnexpectedEntityException(
-                $datetime,
-                'EE_Datetime',
-                sprintf(
-                    __('The ticket (%s) is not associated with any valid datetimes.', 'event_espresso'),
-                    $this->name()
-                )
-            );
-        }
-        $event = $datetime->event();
-        if (! $event instanceof \EE_Event) {
-            throw new UnexpectedEntityException(
-                $event,
-                'EE_Event',
-                sprintf(
-                    __('The ticket (%s) is not associated with a valid event.', 'event_espresso'),
-                    $this->name()
-                )
-            );
-        }
-        return $event;
-    }
-
-
-    /**
-     * Implementation of the EEI_Event_Relation interface method
-     *
-     * @see EEI_Event_Relation for comments
-     * @return string
-     * @throws UnexpectedEntityException
-     * @throws EE_Error
-     */
-    public function get_event_name()
-    {
-        $event = $this->get_related_event();
-        return $event instanceof EE_Event ? $event->name() : '';
-    }
-
-
-    /**
-     * Implementation of the EEI_Event_Relation interface method
-     *
-     * @see EEI_Event_Relation for comments
-     * @return int
-     * @throws UnexpectedEntityException
-     * @throws EE_Error
-     */
-    public function get_event_ID()
-    {
-        $event = $this->get_related_event();
-        return $event instanceof EE_Event ? $event->ID() : 0;
-    }
-
-
-    /**
-     * This simply returns whether a ticket can be permanently deleted or not.
-     * The criteria for determining this is whether the ticket has any related registrations.
-     * If there are none then it can be permanently deleted.
-     *
-     * @return bool
-     */
-    public function is_permanently_deleteable()
-    {
-        return $this->count_registrations() === 0;
-    }
-
-
-    /*******************************************************************
+	/**
+	 * The following constants are used by the ticket_status() method to indicate whether a ticket is on sale or not.
+	 */
+	const sold_out = 'TKS';
+
+	/**
+	 *
+	 */
+	const expired = 'TKE';
+
+	/**
+	 *
+	 */
+	const archived = 'TKA';
+
+	/**
+	 *
+	 */
+	const pending = 'TKP';
+
+	/**
+	 *
+	 */
+	const onsale = 'TKO';
+
+	/**
+	 * extra meta key for tracking ticket reservations
+	 *
+	 * @type string
+	 */
+	const META_KEY_TICKET_RESERVATIONS = 'ticket_reservations';
+
+	/**
+	 * cached result from method of the same name
+	 *
+	 * @var float $_ticket_total_with_taxes
+	 */
+	private $_ticket_total_with_taxes;
+
+
+	/**
+	 * @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  $date_formats            incoming date_formats in an array where the first value is the
+	 *                                        date_format and the second value is the time format
+	 * @return EE_Ticket
+	 * @throws EE_Error
+	 */
+	public static function new_instance($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, $date_formats);
+	}
+
+
+	/**
+	 * @param array  $props_n_values  incoming values from the database
+	 * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
+	 *                                the website will be used.
+	 * @return EE_Ticket
+	 * @throws EE_Error
+	 */
+	public static function new_instance_from_db($props_n_values = array(), $timezone = null)
+	{
+		return new self($props_n_values, true, $timezone);
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 */
+	public function parent()
+	{
+		return $this->get('TKT_parent');
+	}
+
+
+	/**
+	 * return if a ticket has quantities available for purchase
+	 *
+	 * @param  int $DTT_ID the primary key for a particular datetime
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function available($DTT_ID = 0)
+	{
+		// are we checking availability for a particular datetime ?
+		if ($DTT_ID) {
+			// get that datetime object
+			$datetime = $this->get_first_related('Datetime', array(array('DTT_ID' => $DTT_ID)));
+			// if  ticket sales for this datetime have exceeded the reg limit...
+			if ($datetime instanceof EE_Datetime && $datetime->sold_out()) {
+				return false;
+			}
+		}
+		// datetime is still open for registration, but is this ticket sold out ?
+		return $this->qty() < 1 || $this->qty() > $this->sold() ? true : false;
+	}
+
+
+	/**
+	 * Using the start date and end date this method calculates whether the ticket is On Sale, Pending, or Expired
+	 *
+	 * @param bool        $display   true = we'll return a localized string, otherwise we just return the value of the
+	 *                               relevant status const
+	 * @param bool | null $remaining if it is already known that tickets are available, then simply pass a bool to save
+	 *               further processing
+	 * @return mixed status int if the display string isn't requested
+	 * @throws EE_Error
+	 */
+	public function ticket_status($display = false, $remaining = null)
+	{
+		$remaining = is_bool($remaining) ? $remaining : $this->is_remaining();
+		if (! $remaining) {
+			return $display ? EEH_Template::pretty_status(EE_Ticket::sold_out, false, 'sentence') : EE_Ticket::sold_out;
+		}
+		if ($this->get('TKT_deleted')) {
+			return $display ? EEH_Template::pretty_status(EE_Ticket::archived, false, 'sentence') : EE_Ticket::archived;
+		}
+		if ($this->is_expired()) {
+			return $display ? EEH_Template::pretty_status(EE_Ticket::expired, false, 'sentence') : EE_Ticket::expired;
+		}
+		if ($this->is_pending()) {
+			return $display ? EEH_Template::pretty_status(EE_Ticket::pending, false, 'sentence') : EE_Ticket::pending;
+		}
+		if ($this->is_on_sale()) {
+			return $display ? EEH_Template::pretty_status(EE_Ticket::onsale, false, 'sentence') : EE_Ticket::onsale;
+		}
+		return '';
+	}
+
+
+	/**
+	 * The purpose of this method is to simply return a boolean for whether there are any tickets remaining for sale
+	 * considering ALL the factors used for figuring that out.
+	 *
+	 * @access public
+	 * @param  int $DTT_ID if an int above 0 is included here then we get a specific dtt.
+	 * @return boolean         true = tickets remaining, false not.
+	 * @throws EE_Error
+	 */
+	public function is_remaining($DTT_ID = 0)
+	{
+		$num_remaining = $this->remaining($DTT_ID);
+		if ($num_remaining === 0) {
+			return false;
+		}
+		if ($num_remaining > 0 && $num_remaining < $this->min()) {
+			return false;
+		}
+		return true;
+	}
+
+
+	/**
+	 * return the total number of tickets available for purchase
+	 *
+	 * @param  int $DTT_ID the primary key for a particular datetime.
+	 *                     set to 0 for all related datetimes
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function remaining($DTT_ID = 0)
+	{
+		return $this->real_quantity_on_ticket('saleable', $DTT_ID);
+	}
+
+
+	/**
+	 * Gets min
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function min()
+	{
+		return $this->get('TKT_min');
+	}
+
+
+	/**
+	 * return if a ticket is no longer available cause its available dates have expired.
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function is_expired()
+	{
+		return ($this->get_raw('TKT_end_date') < time());
+	}
+
+
+	/**
+	 * Return if a ticket is yet to go on sale or not
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function is_pending()
+	{
+		return ($this->get_raw('TKT_start_date') > time());
+	}
+
+
+	/**
+	 * Return if a ticket is on sale or not
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function is_on_sale()
+	{
+		return ($this->get_raw('TKT_start_date') < time() && $this->get_raw('TKT_end_date') > time());
+	}
+
+
+	/**
+	 * This returns the chronologically last datetime that this ticket is associated with
+	 *
+	 * @param string $dt_frmt
+	 * @param string $conjunction - conjunction junction what's your function ? this string joins the start date with
+	 *                            the end date ie: Jan 01 "to" Dec 31
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function date_range($dt_frmt = '', $conjunction = ' - ')
+	{
+		$first_date = $this->first_datetime() instanceof EE_Datetime ? $this->first_datetime()->start_date($dt_frmt)
+			: '';
+		$last_date = $this->last_datetime() instanceof EE_Datetime ? $this->last_datetime()->end_date($dt_frmt) : '';
+
+		return $first_date && $last_date ? $first_date . $conjunction . $last_date : '';
+	}
+
+
+	/**
+	 * This returns the chronologically first datetime that this ticket is associated with
+	 *
+	 * @return EE_Datetime
+	 * @throws EE_Error
+	 */
+	public function first_datetime()
+	{
+		$datetimes = $this->datetimes(array('limit' => 1));
+		return reset($datetimes);
+	}
+
+
+	/**
+	 * Gets all the datetimes this ticket can be used for attending.
+	 * Unless otherwise specified, orders datetimes by start date.
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Datetime[]|EE_Base_Class[]
+	 * @throws EE_Error
+	 */
+	public function datetimes($query_params = array())
+	{
+		if (! isset($query_params['order_by'])) {
+			$query_params['order_by']['DTT_order'] = 'ASC';
+		}
+		return $this->get_many_related('Datetime', $query_params);
+	}
+
+
+	/**
+	 * This returns the chronologically last datetime that this ticket is associated with
+	 *
+	 * @return EE_Datetime
+	 * @throws EE_Error
+	 */
+	public function last_datetime()
+	{
+		$datetimes = $this->datetimes(array('limit' => 1, 'order_by' => array('DTT_EVT_start' => 'DESC')));
+		return end($datetimes);
+	}
+
+
+	/**
+	 * This returns the total tickets sold depending on the given parameters.
+	 *
+	 * @param  string $what   Can be one of two options: 'ticket', 'datetime'.
+	 *                        'ticket' = total ticket sales for all datetimes this ticket is related to
+	 *                        'datetime' = total ticket sales for a specified datetime (required $dtt_id)
+	 *                        'datetime' = total ticket sales in the datetime_ticket table.
+	 *                        If $dtt_id is not given then we return an array of sales indexed by datetime.
+	 *                        If $dtt_id IS given then we return the tickets sold for that given datetime.
+	 * @param  int    $dtt_id [optional] include the dtt_id with $what = 'datetime'.
+	 * @return mixed (array|int)          how many tickets have sold
+	 * @throws EE_Error
+	 */
+	public function tickets_sold($what = 'ticket', $dtt_id = null)
+	{
+		$total = 0;
+		$tickets_sold = $this->_all_tickets_sold();
+		switch ($what) {
+			case 'ticket':
+				return $tickets_sold['ticket'];
+				break;
+			case 'datetime':
+				if (empty($tickets_sold['datetime'])) {
+					return $total;
+				}
+				if (! empty($dtt_id) && ! isset($tickets_sold['datetime'][ $dtt_id ])) {
+					EE_Error::add_error(
+						__(
+							'You\'ve requested the amount of tickets sold for a given ticket and datetime, however there are no records for the datetime id you included.  Are you SURE that is a datetime related to this ticket?',
+							'event_espresso'
+						),
+						__FILE__,
+						__FUNCTION__,
+						__LINE__
+					);
+					return $total;
+				}
+				return empty($dtt_id) ? $tickets_sold['datetime'] : $tickets_sold['datetime'][ $dtt_id ];
+				break;
+			default:
+				return $total;
+		}
+	}
+
+
+	/**
+	 * This returns an array indexed by datetime_id for tickets sold with this ticket.
+	 *
+	 * @return EE_Ticket[]
+	 * @throws EE_Error
+	 */
+	protected function _all_tickets_sold()
+	{
+		$datetimes = $this->get_many_related('Datetime');
+		$tickets_sold = array();
+		if (! empty($datetimes)) {
+			foreach ($datetimes as $datetime) {
+				$tickets_sold['datetime'][ $datetime->ID() ] = $datetime->get('DTT_sold');
+			}
+		}
+		// Tickets sold
+		$tickets_sold['ticket'] = $this->sold();
+		return $tickets_sold;
+	}
+
+
+	/**
+	 * This returns the base price object for the ticket.
+	 *
+	 * @param  bool $return_array whether to return as an array indexed by price id or just the object.
+	 * @return EE_Price|EE_Base_Class|EE_Price[]|EE_Base_Class[]
+	 * @throws EE_Error
+	 */
+	public function base_price($return_array = false)
+	{
+		$_where = array('Price_Type.PBT_ID' => EEM_Price_Type::base_type_base_price);
+		return $return_array
+			? $this->get_many_related('Price', array($_where))
+			: $this->get_first_related('Price', array($_where));
+	}
+
+
+	/**
+	 * This returns ONLY the price modifiers for the ticket (i.e. no taxes or base price)
+	 *
+	 * @access public
+	 * @return EE_Price[]
+	 * @throws EE_Error
+	 */
+	public function price_modifiers()
+	{
+		$query_params = array(
+			0 => array(
+				'Price_Type.PBT_ID' => array(
+					'NOT IN',
+					array(EEM_Price_Type::base_type_base_price, EEM_Price_Type::base_type_tax),
+				),
+			),
+		);
+		return $this->prices($query_params);
+	}
+
+
+	/**
+	 * Gets all the prices that combine to form the final price of this ticket
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Price[]|EE_Base_Class[]
+	 * @throws EE_Error
+	 */
+	public function prices($query_params = array())
+	{
+		return $this->get_many_related('Price', $query_params);
+	}
+
+
+	/**
+	 * Gets all the ticket applicabilities (ie, relations between datetimes and tickets)
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Datetime_Ticket|EE_Base_Class[]
+	 * @throws EE_Error
+	 */
+	public function datetime_tickets($query_params = array())
+	{
+		return $this->get_many_related('Datetime_Ticket', $query_params);
+	}
+
+
+	/**
+	 * Gets all the datetimes from the db ordered by DTT_order
+	 *
+	 * @param boolean $show_expired
+	 * @param boolean $show_deleted
+	 * @return EE_Datetime[]
+	 * @throws EE_Error
+	 */
+	public function datetimes_ordered($show_expired = true, $show_deleted = false)
+	{
+		return EEM_Datetime::instance($this->_timezone)->get_datetimes_for_ticket_ordered_by_DTT_order(
+			$this->ID(),
+			$show_expired,
+			$show_deleted
+		);
+	}
+
+
+	/**
+	 * Gets ID
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function ID()
+	{
+		return $this->get('TKT_ID');
+	}
+
+
+	/**
+	 * get the author of the ticket.
+	 *
+	 * @since 4.5.0
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function wp_user()
+	{
+		return $this->get('TKT_wp_user');
+	}
+
+
+	/**
+	 * Gets the template for the ticket
+	 *
+	 * @return EE_Ticket_Template|EE_Base_Class
+	 * @throws EE_Error
+	 */
+	public function template()
+	{
+		return $this->get_first_related('Ticket_Template');
+	}
+
+
+	/**
+	 * Simply returns an array of EE_Price objects that are taxes.
+	 *
+	 * @return EE_Price[]
+	 * @throws EE_Error
+	 */
+	public function get_ticket_taxes_for_admin()
+	{
+		return EE_Taxes::get_taxes_for_admin();
+	}
+
+
+	/**
+	 * @return float
+	 * @throws EE_Error
+	 */
+	public function ticket_price()
+	{
+		return $this->get('TKT_price');
+	}
+
+
+	/**
+	 * @return mixed
+	 * @throws EE_Error
+	 */
+	public function pretty_price()
+	{
+		return $this->get_pretty('TKT_price');
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 */
+	public function is_free()
+	{
+		return $this->get_ticket_total_with_taxes() === (float) 0;
+	}
+
+
+	/**
+	 * get_ticket_total_with_taxes
+	 *
+	 * @param bool $no_cache
+	 * @return float
+	 * @throws EE_Error
+	 */
+	public function get_ticket_total_with_taxes($no_cache = false)
+	{
+		if ($this->_ticket_total_with_taxes === null || $no_cache) {
+			$this->_ticket_total_with_taxes = $this->get_ticket_subtotal() + $this->get_ticket_taxes_total_for_admin();
+		}
+		return (float) $this->_ticket_total_with_taxes;
+	}
+
+
+	public function ensure_TKT_Price_correct()
+	{
+		$this->set('TKT_price', EE_Taxes::get_subtotal_for_admin($this));
+		$this->save();
+	}
+
+
+	/**
+	 * @return float
+	 * @throws EE_Error
+	 */
+	public function get_ticket_subtotal()
+	{
+		return EE_Taxes::get_subtotal_for_admin($this);
+	}
+
+
+	/**
+	 * Returns the total taxes applied to this ticket
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 */
+	public function get_ticket_taxes_total_for_admin()
+	{
+		return EE_Taxes::get_total_taxes_for_admin($this);
+	}
+
+
+	/**
+	 * Sets name
+	 *
+	 * @param string $name
+	 * @throws EE_Error
+	 */
+	public function set_name($name)
+	{
+		$this->set('TKT_name', $name);
+	}
+
+
+	/**
+	 * Gets description
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function description()
+	{
+		return $this->get('TKT_description');
+	}
+
+
+	/**
+	 * Sets description
+	 *
+	 * @param string $description
+	 * @throws EE_Error
+	 */
+	public function set_description($description)
+	{
+		$this->set('TKT_description', $description);
+	}
+
+
+	/**
+	 * Gets start_date
+	 *
+	 * @param string $dt_frmt
+	 * @param string $tm_frmt
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function start_date($dt_frmt = '', $tm_frmt = '')
+	{
+		return $this->_get_datetime('TKT_start_date', $dt_frmt, $tm_frmt);
+	}
+
+
+	/**
+	 * Sets start_date
+	 *
+	 * @param string $start_date
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_start_date($start_date)
+	{
+		$this->_set_date_time('B', $start_date, 'TKT_start_date');
+	}
+
+
+	/**
+	 * Gets end_date
+	 *
+	 * @param string $dt_frmt
+	 * @param string $tm_frmt
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function end_date($dt_frmt = '', $tm_frmt = '')
+	{
+		return $this->_get_datetime('TKT_end_date', $dt_frmt, $tm_frmt);
+	}
+
+
+	/**
+	 * Sets end_date
+	 *
+	 * @param string $end_date
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_end_date($end_date)
+	{
+		$this->_set_date_time('B', $end_date, 'TKT_end_date');
+	}
+
+
+	/**
+	 * Sets sell until time
+	 *
+	 * @since 4.5.0
+	 * @param string $time a string representation of the sell until time (ex 9am or 7:30pm)
+	 * @throws EE_Error
+	 */
+	public function set_end_time($time)
+	{
+		$this->_set_time_for($time, 'TKT_end_date');
+	}
+
+
+	/**
+	 * Sets min
+	 *
+	 * @param int $min
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_min($min)
+	{
+		$this->set('TKT_min', $min);
+	}
+
+
+	/**
+	 * Gets max
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function max()
+	{
+		return $this->get('TKT_max');
+	}
+
+
+	/**
+	 * Sets max
+	 *
+	 * @param int $max
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_max($max)
+	{
+		$this->set('TKT_max', $max);
+	}
+
+
+	/**
+	 * Sets price
+	 *
+	 * @param float $price
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_price($price)
+	{
+		$this->set('TKT_price', $price);
+	}
+
+
+	/**
+	 * Gets sold
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function sold()
+	{
+		return $this->get_raw('TKT_sold');
+	}
+
+
+	/**
+	 * Sets sold
+	 *
+	 * @param int $sold
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_sold($sold)
+	{
+		// sold can not go below zero
+		$sold = max(0, $sold);
+		$this->set('TKT_sold', $sold);
+	}
+
+
+	/**
+	 * Increments sold by amount passed by $qty AND decrements the reserved count on both this ticket and its
+	 * associated datetimes.
+	 *
+	 * @since $VID:$
+	 * @param int $qty
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function increaseSold($qty = 1)
+	{
+		$qty = absint($qty);
+		// increment sold and decrement reserved datetime quantities simultaneously
+		// don't worry about failures, because they must have already had a spot reserved
+		$this->increaseSoldForDatetimes($qty);
+		// Increment and decrement ticket quantities simultaneously
+		$success = $this->adjustNumericFieldsInDb(
+			[
+				'TKT_reserved' => $qty * -1,
+				'TKT_sold' => $qty
+			]
+		);
+		do_action(
+			'AHEE__EE_Ticket__increase_sold',
+			$this,
+			$qty,
+			$this->sold(),
+			$success
+		);
+		return $success;
+	}
+
+	/**
+	 * On each datetime related to this ticket, increases its sold count and decreases its reserved count by $qty.
+	 *
+	 * @since $VID:$
+	 * @param int $qty positive or negative. Positive means to increase sold counts (and decrease reserved counts),
+	 *             Negative means to decreases old counts (and increase reserved counts).
+	 * @param EE_Datetime[] $datetimes
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function increaseSoldForDatetimes($qty, array $datetimes = [])
+	{
+		$datetimes = ! empty($datetimes) ? $datetimes : $this->datetimes();
+		foreach ($datetimes as $datetime) {
+			$datetime->increaseSold($qty);
+		}
+	}
+
+
+
+	/**
+	 * Decrements (subtracts) sold by amount passed by $qty on both the ticket and its related datetimes directly in the
+	 * DB and then updates the model objects.
+	 * Does not affect the reserved counts.
+	 *
+	 * @since $VID:$
+	 * @param int $qty
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function decreaseSold($qty = 1)
+	{
+		$qty = absint($qty);
+		$this->decreaseSoldForDatetimes($qty);
+		$success = $this->adjustNumericFieldsInDb(
+			[
+				'TKT_sold' => $qty * -1
+			]
+		);
+		do_action(
+			'AHEE__EE_Ticket__decrease_sold',
+			$this,
+			$qty,
+			$this->sold(),
+			$success
+		);
+		return $success;
+	}
+
+
+	/**
+	 * Decreases sold on related datetimes
+	 *
+	 * @since $VID:$
+	 * @param int $qty
+	 * @param EE_Datetime[] $datetimes
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function decreaseSoldForDatetimes($qty = 1, array $datetimes = [])
+	{
+		$datetimes = ! empty($datetimes) ? $datetimes : $this->datetimes();
+		if (is_array($datetimes)) {
+			foreach ($datetimes as $datetime) {
+				if ($datetime instanceof EE_Datetime) {
+					$datetime->decreaseSold($qty);
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * Gets qty of reserved tickets
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function reserved()
+	{
+		return $this->get_raw('TKT_reserved');
+	}
+
+
+	/**
+	 * Sets reserved
+	 *
+	 * @param int $reserved
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_reserved($reserved)
+	{
+		// reserved can not go below zero
+		$reserved = max(0, (int) $reserved);
+		$this->set('TKT_reserved', $reserved);
+	}
+
+
+	/**
+	 * Increments reserved by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @since $VID:$
+	 * @param int    $qty
+	 * @param string $source
+	 * @return bool whether we successfully reserved the ticket or not.
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function increaseReserved($qty = 1, $source = 'unknown')
+	{
+		$qty = absint($qty);
+		do_action(
+			'AHEE__EE_Ticket__increase_reserved__begin',
+			$this,
+			$qty,
+			$source
+		);
+		$this->add_extra_meta(EE_Ticket::META_KEY_TICKET_RESERVATIONS, "{$qty} from {$source}");
+		$success = false;
+		$datetimes_adjusted_successfully = $this->increaseReservedForDatetimes($qty);
+		if ($datetimes_adjusted_successfully) {
+			$success = $this->incrementFieldConditionallyInDb(
+				'TKT_reserved',
+				'TKT_sold',
+				'TKT_qty',
+				$qty
+			);
+			if (! $success) {
+				// The datetimes were successfully bumped, but not the
+				// ticket. So we need to manually rollback the datetimes.
+				$this->decreaseReservedForDatetimes($qty);
+			}
+		}
+		do_action(
+			'AHEE__EE_Ticket__increase_reserved',
+			$this,
+			$qty,
+			$this->reserved(),
+			$success
+		);
+		return $success;
+	}
+
+
+	/**
+	 * Increases reserved counts on related datetimes
+	 *
+	 * @since $VID:$
+	 * @param int $qty
+	 * @param EE_Datetime[] $datetimes
+	 * @return boolean indicating success
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function increaseReservedForDatetimes($qty = 1, array $datetimes = [])
+	{
+		$datetimes = ! empty($datetimes) ? $datetimes : $this->datetimes();
+		$datetimes_updated = [];
+		$limit_exceeded = false;
+		if (is_array($datetimes)) {
+			foreach ($datetimes as $datetime) {
+				if ($datetime instanceof EE_Datetime) {
+					if ($datetime->increaseReserved($qty)) {
+						$datetimes_updated[] = $datetime;
+					} else {
+						$limit_exceeded = true;
+						break;
+					}
+				}
+			}
+			// If somewhere along the way we detected a datetime whose
+			// limit was exceeded, do a manual rollback.
+			if ($limit_exceeded) {
+				$this->decreaseReservedForDatetimes($qty, $datetimes_updated);
+				return false;
+			}
+		}
+		return true;
+	}
+
+
+	/**
+	 * Decrements (subtracts) reserved by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @since $VID:$
+	 * @param int    $qty
+	 * @param bool   $adjust_datetimes
+	 * @param string $source
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function decreaseReserved($qty = 1, $adjust_datetimes = true, $source = 'unknown')
+	{
+		$qty = absint($qty);
+		$this->add_extra_meta(EE_Ticket::META_KEY_TICKET_RESERVATIONS, "-{$qty} from {$source}");
+		if ($adjust_datetimes) {
+			$this->decreaseReservedForDatetimes($qty);
+		}
+		$success = $this->adjustNumericFieldsInDb(
+			[
+				'TKT_reserved' => $qty * -1
+			]
+		);
+		do_action(
+			'AHEE__EE_Ticket__decrease_reserved',
+			$this,
+			$qty,
+			$this->reserved(),
+			$success
+		);
+		return $success;
+	}
+
+
+	/**
+	 * Decreases the reserved count on the specified datetimes.
+	 *
+	 * @since $VID:$
+	 * @param int           $qty
+	 * @param EE_Datetime[] $datetimes
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function decreaseReservedForDatetimes($qty = 1, array $datetimes = [])
+	{
+		$datetimes = ! empty($datetimes) ? $datetimes : $this->datetimes();
+		foreach ($datetimes as $datetime) {
+			if ($datetime instanceof EE_Datetime) {
+				$datetime->decreaseReserved($qty);
+			}
+		}
+	}
+
+
+	/**
+	 * Gets ticket quantity
+	 *
+	 * @param string $context     ticket quantity is somewhat subjective depending on the exact information sought
+	 *                            therefore $context can be one of three values: '', 'reg_limit', or 'saleable'
+	 *                            '' (default) quantity is the actual db value for TKT_qty, unaffected by other objects
+	 *                            REG LIMIT: caps qty based on DTT_reg_limit for ALL related datetimes
+	 *                            SALEABLE: also considers datetime sold and returns zero if ANY DTT is sold out, and
+	 *                            is therefore the truest measure of tickets that can be purchased at the moment
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function qty($context = '')
+	{
+		switch ($context) {
+			case 'reg_limit':
+				return $this->real_quantity_on_ticket();
+			case 'saleable':
+				return $this->real_quantity_on_ticket('saleable');
+			default:
+				return $this->get_raw('TKT_qty');
+		}
+	}
+
+
+	/**
+	 * Gets ticket quantity
+	 *
+	 * @param string $context     ticket quantity is somewhat subjective depending on the exact information sought
+	 *                            therefore $context can be one of two values: 'reg_limit', or 'saleable'
+	 *                            REG LIMIT: caps qty based on DTT_reg_limit for ALL related datetimes
+	 *                            SALEABLE: also considers datetime sold and returns zero if ANY DTT is sold out, and
+	 *                            is therefore the truest measure of tickets that can be purchased at the moment
+	 * @param  int   $DTT_ID      the primary key for a particular datetime.
+	 *                            set to 0 for all related datetimes
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function real_quantity_on_ticket($context = 'reg_limit', $DTT_ID = 0)
+	{
+		$raw = $this->get_raw('TKT_qty');
+		// return immediately if it's zero
+		if ($raw === 0) {
+			return $raw;
+		}
+		// echo "\n\n<br />Ticket: " . $this->name() . '<br />';
+		// ensure qty doesn't exceed raw value for THIS ticket
+		$qty = min(EE_INF, $raw);
+		// echo "\n . qty: " . $qty . '<br />';
+		// calculate this ticket's total sales and reservations
+		$sold_and_reserved_for_this_ticket = $this->sold() + $this->reserved();
+		// echo "\n . sold: " . $this->sold() . '<br />';
+		// echo "\n . reserved: " . $this->reserved() . '<br />';
+		// echo "\n . sold_and_reserved_for_this_ticket: " . $sold_and_reserved_for_this_ticket . '<br />';
+		// first we need to calculate the maximum number of tickets available for the datetime
+		// do we want data for one datetime or all of them ?
+		$query_params = $DTT_ID ? array(array('DTT_ID' => $DTT_ID)) : array();
+		$datetimes = $this->datetimes($query_params);
+		if (is_array($datetimes) && ! empty($datetimes)) {
+			foreach ($datetimes as $datetime) {
+				if ($datetime instanceof EE_Datetime) {
+					$datetime->refresh_from_db();
+					// echo "\n . . datetime name: " . $datetime->name() . '<br />';
+					// echo "\n . . datetime ID: " . $datetime->ID() . '<br />';
+					// initialize with no restrictions for each datetime
+					// but adjust datetime qty based on datetime reg limit
+					$datetime_qty = min(EE_INF, $datetime->reg_limit());
+					// echo "\n . . . datetime reg_limit: " . $datetime->reg_limit() . '<br />';
+					// echo "\n . . . datetime_qty: " . $datetime_qty . '<br />';
+					// if we want the actual saleable amount, then we need to consider OTHER ticket sales
+					// and reservations for this datetime, that do NOT include sales and reservations
+					// for this ticket (so we add $this->sold() and $this->reserved() back in)
+					if ($context === 'saleable') {
+						$datetime_qty = max(
+							$datetime_qty - $datetime->sold_and_reserved() + $sold_and_reserved_for_this_ticket,
+							0
+						);
+						// echo "\n . . . datetime sold: " . $datetime->sold() . '<br />';
+						// echo "\n . . . datetime reserved: " . $datetime->reserved() . '<br />';
+						// echo "\n . . . datetime sold_and_reserved: " . $datetime->sold_and_reserved() . '<br />';
+						// echo "\n . . . datetime_qty: " . $datetime_qty . '<br />';
+						$datetime_qty = ! $datetime->sold_out() ? $datetime_qty : 0;
+						// echo "\n . . . datetime_qty: " . $datetime_qty . '<br />';
+					}
+					$qty = min($datetime_qty, $qty);
+					// echo "\n . . qty: " . $qty . '<br />';
+				}
+			}
+		}
+		// NOW that we know the  maximum number of tickets available for the datetime
+		// we can finally factor in the details for this specific ticket
+		if ($qty > 0 && $context === 'saleable') {
+			// and subtract the sales for THIS ticket
+			$qty = max($qty - $sold_and_reserved_for_this_ticket, 0);
+			// echo "\n . qty: " . $qty . '<br />';
+		}
+		// echo "\nFINAL QTY: " . $qty . "<br /><br />";
+		return $qty;
+	}
+
+
+	/**
+	 * Sets qty - IMPORTANT!!! Does NOT allow QTY to be set higher than the lowest reg limit of any related datetimes
+	 *
+	 * @param int $qty
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_qty($qty)
+	{
+		$datetimes = $this->datetimes();
+		foreach ($datetimes as $datetime) {
+			if ($datetime instanceof EE_Datetime) {
+				$qty = min($qty, $datetime->reg_limit());
+			}
+		}
+		$this->set('TKT_qty', $qty);
+	}
+
+
+	/**
+	 * Gets uses
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function uses()
+	{
+		return $this->get('TKT_uses');
+	}
+
+
+	/**
+	 * Sets uses
+	 *
+	 * @param int $uses
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_uses($uses)
+	{
+		$this->set('TKT_uses', $uses);
+	}
+
+
+	/**
+	 * returns whether ticket is required or not.
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function required()
+	{
+		return $this->get('TKT_required');
+	}
+
+
+	/**
+	 * sets the TKT_required property
+	 *
+	 * @param boolean $required
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_required($required)
+	{
+		$this->set('TKT_required', $required);
+	}
+
+
+	/**
+	 * Gets taxable
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function taxable()
+	{
+		return $this->get('TKT_taxable');
+	}
+
+
+	/**
+	 * Sets taxable
+	 *
+	 * @param boolean $taxable
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_taxable($taxable)
+	{
+		$this->set('TKT_taxable', $taxable);
+	}
+
+
+	/**
+	 * Gets is_default
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function is_default()
+	{
+		return $this->get('TKT_is_default');
+	}
+
+
+	/**
+	 * Sets is_default
+	 *
+	 * @param boolean $is_default
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_is_default($is_default)
+	{
+		$this->set('TKT_is_default', $is_default);
+	}
+
+
+	/**
+	 * Gets order
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function order()
+	{
+		return $this->get('TKT_order');
+	}
+
+
+	/**
+	 * Sets order
+	 *
+	 * @param int $order
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_order($order)
+	{
+		$this->set('TKT_order', $order);
+	}
+
+
+	/**
+	 * Gets row
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function row()
+	{
+		return $this->get('TKT_row');
+	}
+
+
+	/**
+	 * Sets row
+	 *
+	 * @param int $row
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_row($row)
+	{
+		$this->set('TKT_row', $row);
+	}
+
+
+	/**
+	 * Gets deleted
+	 *
+	 * @return boolean
+	 * @throws EE_Error
+	 */
+	public function deleted()
+	{
+		return $this->get('TKT_deleted');
+	}
+
+
+	/**
+	 * Sets deleted
+	 *
+	 * @param boolean $deleted
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_deleted($deleted)
+	{
+		$this->set('TKT_deleted', $deleted);
+	}
+
+
+	/**
+	 * Gets parent
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function parent_ID()
+	{
+		return $this->get('TKT_parent');
+	}
+
+
+	/**
+	 * Sets parent
+	 *
+	 * @param int $parent
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public function set_parent_ID($parent)
+	{
+		$this->set('TKT_parent', $parent);
+	}
+
+
+	/**
+	 * Gets a string which is handy for showing in gateways etc that describes the ticket.
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function name_and_info()
+	{
+		$times = array();
+		foreach ($this->datetimes() as $datetime) {
+			$times[] = $datetime->start_date_and_time();
+		}
+		return $this->name() . ' @ ' . implode(', ', $times) . ' for ' . $this->pretty_price();
+	}
+
+
+	/**
+	 * Gets name
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 */
+	public function name()
+	{
+		return $this->get('TKT_name');
+	}
+
+
+	/**
+	 * Gets price
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 */
+	public function price()
+	{
+		return $this->get('TKT_price');
+	}
+
+
+	/**
+	 * Gets all the registrations for this ticket
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Registration[]|EE_Base_Class[]
+	 * @throws EE_Error
+	 */
+	public function registrations($query_params = array())
+	{
+		return $this->get_many_related('Registration', $query_params);
+	}
+
+
+	/**
+	 * Updates the TKT_sold attribute (and saves) based on the number of APPROVED registrations for this ticket.
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 */
+	public function update_tickets_sold()
+	{
+		$count_regs_for_this_ticket = $this->count_registrations(
+			array(
+				array(
+					'STS_ID'      => EEM_Registration::status_id_approved,
+					'REG_deleted' => 0,
+				),
+			)
+		);
+		$this->set_sold($count_regs_for_this_ticket);
+		$this->save();
+		return $count_regs_for_this_ticket;
+	}
+
+
+	/**
+	 * Counts the registrations for this ticket
+	 *
+	 * @param array $query_params @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return int
+	 */
+	public function count_registrations($query_params = array())
+	{
+		return $this->count_related('Registration', $query_params);
+	}
+
+
+	/**
+	 * Implementation for EEI_Has_Icon interface method.
+	 *
+	 * @see EEI_Visual_Representation for comments
+	 * @return string
+	 */
+	public function get_icon()
+	{
+		return '<span class="dashicons dashicons-tickets-alt"></span>';
+	}
+
+
+	/**
+	 * Implementation of the EEI_Event_Relation interface method
+	 *
+	 * @see EEI_Event_Relation for comments
+	 * @return EE_Event
+	 * @throws EE_Error
+	 * @throws UnexpectedEntityException
+	 */
+	public function get_related_event()
+	{
+		// get one datetime to use for getting the event
+		$datetime = $this->first_datetime();
+		if (! $datetime instanceof \EE_Datetime) {
+			throw new UnexpectedEntityException(
+				$datetime,
+				'EE_Datetime',
+				sprintf(
+					__('The ticket (%s) is not associated with any valid datetimes.', 'event_espresso'),
+					$this->name()
+				)
+			);
+		}
+		$event = $datetime->event();
+		if (! $event instanceof \EE_Event) {
+			throw new UnexpectedEntityException(
+				$event,
+				'EE_Event',
+				sprintf(
+					__('The ticket (%s) is not associated with a valid event.', 'event_espresso'),
+					$this->name()
+				)
+			);
+		}
+		return $event;
+	}
+
+
+	/**
+	 * Implementation of the EEI_Event_Relation interface method
+	 *
+	 * @see EEI_Event_Relation for comments
+	 * @return string
+	 * @throws UnexpectedEntityException
+	 * @throws EE_Error
+	 */
+	public function get_event_name()
+	{
+		$event = $this->get_related_event();
+		return $event instanceof EE_Event ? $event->name() : '';
+	}
+
+
+	/**
+	 * Implementation of the EEI_Event_Relation interface method
+	 *
+	 * @see EEI_Event_Relation for comments
+	 * @return int
+	 * @throws UnexpectedEntityException
+	 * @throws EE_Error
+	 */
+	public function get_event_ID()
+	{
+		$event = $this->get_related_event();
+		return $event instanceof EE_Event ? $event->ID() : 0;
+	}
+
+
+	/**
+	 * This simply returns whether a ticket can be permanently deleted or not.
+	 * The criteria for determining this is whether the ticket has any related registrations.
+	 * If there are none then it can be permanently deleted.
+	 *
+	 * @return bool
+	 */
+	public function is_permanently_deleteable()
+	{
+		return $this->count_registrations() === 0;
+	}
+
+
+	/*******************************************************************
      ***********************  DEPRECATED METHODS  **********************
      *******************************************************************/
 
 
-    /**
-     * Increments sold by amount passed by $qty AND decrements the reserved count on both this ticket and its
-     * associated datetimes.
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function increase_sold($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Ticket::increaseSold() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        $this->increaseSold($qty);
-    }
-
-
-    /**
-     * On each datetime related to this ticket, increases its sold count and decreases its reserved count by $qty.
-     *
-     * @deprecated $VID:$
-     * @param int $qty positive or negative. Positive means to increase sold counts (and decrease reserved counts),
-     *                 Negative means to decreases old counts (and increase reserved counts).
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _increase_sold_for_datetimes($qty)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Ticket::increaseSoldForDatetimes() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        $this->increaseSoldForDatetimes($qty);
-    }
-
-
-    /**
-     * Decrements (subtracts) sold by amount passed by $qty on both the ticket and its related datetimes directly in the
-     * DB and then updates the model objects.
-     * Does not affect the reserved counts.
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function decrease_sold($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Ticket::decreaseSold() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        $this->decreaseSold($qty);
-    }
-
-
-    /**
-     * Decreases sold on related datetimes
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _decrease_sold_for_datetimes($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Ticket::decreaseSoldForDatetimes() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        $this->decreaseSoldForDatetimes($qty);
-    }
-
-
-    /**
-     * Increments reserved by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @deprecated $VID:$
-     * @param int    $qty
-     * @param string $source
-     * @return bool whether we successfully reserved the ticket or not.
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function increase_reserved($qty = 1, $source = 'unknown')
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Ticket::increaseReserved() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        return $this->increaseReserved($qty);
-    }
-
-
-    /**
-     * Increases sold on related datetimes
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return boolean indicating success
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _increase_reserved_for_datetimes($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Ticket::increaseReservedForDatetimes() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        return $this->increaseReservedForDatetimes($qty);
-    }
-
-
-    /**
-     * Decrements (subtracts) reserved by amount passed by $qty, and persists it immediately to the database.
-     *
-     * @deprecated $VID:$
-     * @param int    $qty
-     * @param bool   $adjust_datetimes
-     * @param string $source
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function decrease_reserved($qty = 1, $adjust_datetimes = true, $source = 'unknown')
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Ticket::decreaseReserved() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        $this->decreaseReserved($qty);
-    }
-
-
-    /**
-     * Decreases reserved on related datetimes
-     *
-     * @deprecated $VID:$
-     * @param int $qty
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _decrease_reserved_for_datetimes($qty = 1)
-    {
-        EE_Error::doing_it_wrong(
-            __FUNCTION__,
-            esc_html__('Please use EE_Ticket::decreaseReservedForDatetimes() instead', 'event_espresso'),
-            '$VID:$',
-            '5.0.0.p'
-        );
-        $this->decreaseReservedForDatetimes($qty);
-    }
+	/**
+	 * Increments sold by amount passed by $qty AND decrements the reserved count on both this ticket and its
+	 * associated datetimes.
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function increase_sold($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Ticket::increaseSold() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		$this->increaseSold($qty);
+	}
+
+
+	/**
+	 * On each datetime related to this ticket, increases its sold count and decreases its reserved count by $qty.
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty positive or negative. Positive means to increase sold counts (and decrease reserved counts),
+	 *                 Negative means to decreases old counts (and increase reserved counts).
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _increase_sold_for_datetimes($qty)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Ticket::increaseSoldForDatetimes() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		$this->increaseSoldForDatetimes($qty);
+	}
+
+
+	/**
+	 * Decrements (subtracts) sold by amount passed by $qty on both the ticket and its related datetimes directly in the
+	 * DB and then updates the model objects.
+	 * Does not affect the reserved counts.
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function decrease_sold($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Ticket::decreaseSold() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		$this->decreaseSold($qty);
+	}
+
+
+	/**
+	 * Decreases sold on related datetimes
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _decrease_sold_for_datetimes($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Ticket::decreaseSoldForDatetimes() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		$this->decreaseSoldForDatetimes($qty);
+	}
+
+
+	/**
+	 * Increments reserved by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @deprecated $VID:$
+	 * @param int    $qty
+	 * @param string $source
+	 * @return bool whether we successfully reserved the ticket or not.
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function increase_reserved($qty = 1, $source = 'unknown')
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Ticket::increaseReserved() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		return $this->increaseReserved($qty);
+	}
+
+
+	/**
+	 * Increases sold on related datetimes
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return boolean indicating success
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _increase_reserved_for_datetimes($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Ticket::increaseReservedForDatetimes() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		return $this->increaseReservedForDatetimes($qty);
+	}
+
+
+	/**
+	 * Decrements (subtracts) reserved by amount passed by $qty, and persists it immediately to the database.
+	 *
+	 * @deprecated $VID:$
+	 * @param int    $qty
+	 * @param bool   $adjust_datetimes
+	 * @param string $source
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function decrease_reserved($qty = 1, $adjust_datetimes = true, $source = 'unknown')
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Ticket::decreaseReserved() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		$this->decreaseReserved($qty);
+	}
+
+
+	/**
+	 * Decreases reserved on related datetimes
+	 *
+	 * @deprecated $VID:$
+	 * @param int $qty
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _decrease_reserved_for_datetimes($qty = 1)
+	{
+		EE_Error::doing_it_wrong(
+			__FUNCTION__,
+			esc_html__('Please use EE_Ticket::decreaseReservedForDatetimes() instead', 'event_espresso'),
+			'$VID:$',
+			'5.0.0.p'
+		);
+		$this->decreaseReservedForDatetimes($qty);
+	}
 }

Spacing +11 added lines, -11 removed lines

@@ -129,7 +129,7 @@ 
     public function ticket_status($display = false, $remaining = null)
     {
         $remaining = is_bool($remaining) ? $remaining : $this->is_remaining();
-        if (! $remaining) {
+        if ( ! $remaining) {
             return $display ? EEH_Template::pretty_status(EE_Ticket::sold_out, false, 'sentence') : EE_Ticket::sold_out;
         }
         if ($this->get('TKT_deleted')) {
@@ -247,7 +247,7 @@ 
             : '';
         $last_date = $this->last_datetime() instanceof EE_Datetime ? $this->last_datetime()->end_date($dt_frmt) : '';
 
-        return $first_date && $last_date ? $first_date . $conjunction . $last_date : '';
+        return $first_date && $last_date ? $first_date.$conjunction.$last_date : '';
     }
 
 
@@ -274,7 +274,7 @@ 
      */
     public function datetimes($query_params = array())
     {
-        if (! isset($query_params['order_by'])) {
+        if ( ! isset($query_params['order_by'])) {
             $query_params['order_by']['DTT_order'] = 'ASC';
         }
         return $this->get_many_related('Datetime', $query_params);
@@ -319,7 +319,7 @@ 
                 if (empty($tickets_sold['datetime'])) {
                     return $total;
                 }
-                if (! empty($dtt_id) && ! isset($tickets_sold['datetime'][ $dtt_id ])) {
+                if ( ! empty($dtt_id) && ! isset($tickets_sold['datetime'][$dtt_id])) {
                     EE_Error::add_error(
                         __(
                             'You\'ve requested the amount of tickets sold for a given ticket and datetime, however there are no records for the datetime id you included.  Are you SURE that is a datetime related to this ticket?',
@@ -331,7 +331,7 @@ 
                     );
                     return $total;
                 }
-                return empty($dtt_id) ? $tickets_sold['datetime'] : $tickets_sold['datetime'][ $dtt_id ];
+                return empty($dtt_id) ? $tickets_sold['datetime'] : $tickets_sold['datetime'][$dtt_id];
                 break;
             default:
                 return $total;
@@ -349,9 +349,9 @@ 
     {
         $datetimes = $this->get_many_related('Datetime');
         $tickets_sold = array();
-        if (! empty($datetimes)) {
+        if ( ! empty($datetimes)) {
             foreach ($datetimes as $datetime) {
-                $tickets_sold['datetime'][ $datetime->ID() ] = $datetime->get('DTT_sold');
+                $tickets_sold['datetime'][$datetime->ID()] = $datetime->get('DTT_sold');
             }
         }
         // Tickets sold
@@ -924,7 +924,7 @@ 
                 'TKT_qty',
                 $qty
             );
-            if (! $success) {
+            if ( ! $success) {
                 // The datetimes were successfully bumped, but not the
                 // ticket. So we need to manually rollback the datetimes.
                 $this->decreaseReservedForDatetimes($qty);
@@ -1373,7 +1373,7 @@ 
         foreach ($this->datetimes() as $datetime) {
             $times[] = $datetime->start_date_and_time();
         }
-        return $this->name() . ' @ ' . implode(', ', $times) . ' for ' . $this->pretty_price();
+        return $this->name().' @ '.implode(', ', $times).' for '.$this->pretty_price();
     }
 
 
@@ -1472,7 +1472,7 @@ 
     {
         // get one datetime to use for getting the event
         $datetime = $this->first_datetime();
-        if (! $datetime instanceof \EE_Datetime) {
+        if ( ! $datetime instanceof \EE_Datetime) {
             throw new UnexpectedEntityException(
                 $datetime,
                 'EE_Datetime',
@@ -1483,7 +1483,7 @@ 
             );
         }
         $event = $datetime->event();
-        if (! $event instanceof \EE_Event) {
+        if ( ! $event instanceof \EE_Event) {
             throw new UnexpectedEntityException(
                 $event,
                 'EE_Event',

modules/ticket_sales_monitor/EED_Ticket_Sales_Monitor.module.php

Indentation +1045 added lines, -1045 removed lines

@@ -20,1050 +20,1050 @@
 class EED_Ticket_Sales_Monitor extends EED_Module
 {
 
-    const debug = false;
-
-    private static $nl = '';
-
-    /**
-     * an array of raw ticket data from EED_Ticket_Selector
-     *
-     * @var array $ticket_selections
-     */
-    protected $ticket_selections = array();
-
-    /**
-     * the raw ticket data from EED_Ticket_Selector is organized in rows
-     * according to how they are displayed in the actual Ticket_Selector
-     * this tracks the current row being processed
-     *
-     * @var int $current_row
-     */
-    protected $current_row = 0;
-
-    /**
-     * an array for tracking names of tickets that have sold out
-     *
-     * @var array $sold_out_tickets
-     */
-    protected $sold_out_tickets = array();
-
-    /**
-     * an array for tracking names of tickets that have had their quantities reduced
-     *
-     * @var array $decremented_tickets
-     */
-    protected $decremented_tickets = array();
-
-
-    /**
-     * set_hooks - for hooking into EE Core, other modules, etc
-     *
-     * @return    void
-     */
-    public static function set_hooks()
-    {
-        self::$nl = defined('EE_TESTS_DIR') ? "\n" : '<br />';
-        // release tickets for expired carts
-        add_action(
-            'EED_Ticket_Selector__process_ticket_selections__before',
-            array('EED_Ticket_Sales_Monitor', 'release_tickets_for_expired_carts'),
-            1
-        );
-        // check ticket reserves AFTER MER does it's check (hence priority 20)
-        add_filter(
-            'FHEE__EE_Ticket_Selector___add_ticket_to_cart__ticket_qty',
-            array('EED_Ticket_Sales_Monitor', 'validate_ticket_sale'),
-            20,
-            3
-        );
-        // add notices for sold out tickets
-        add_action(
-            'AHEE__EE_Ticket_Selector__process_ticket_selections__after_tickets_added_to_cart',
-            array('EED_Ticket_Sales_Monitor', 'post_notices'),
-            10
-        );
-
-        // handle tickets deleted from cart
-        add_action(
-            'FHEE__EED_Multi_Event_Registration__delete_ticket__ticket_removed_from_cart',
-            array('EED_Ticket_Sales_Monitor', 'ticket_removed_from_cart'),
-            10,
-            2
-        );
-        // handle emptied carts
-        add_action(
-            'AHEE__EE_Session__reset_cart__before_reset',
-            array('EED_Ticket_Sales_Monitor', 'session_cart_reset'),
-            10,
-            1
-        );
-        add_action(
-            'AHEE__EED_Multi_Event_Registration__empty_event_cart__before_delete_cart',
-            array('EED_Ticket_Sales_Monitor', 'session_cart_reset'),
-            10,
-            1
-        );
-        // handle cancelled registrations
-        add_action(
-            'AHEE__EE_Session__reset_checkout__before_reset',
-            array('EED_Ticket_Sales_Monitor', 'session_checkout_reset'),
-            10,
-            1
-        );
-        // cron tasks
-        add_action(
-            'AHEE__EE_Cron_Tasks__process_expired_transactions__abandoned_transaction',
-            array('EED_Ticket_Sales_Monitor', 'process_abandoned_transactions'),
-            10,
-            1
-        );
-        add_action(
-            'AHEE__EE_Cron_Tasks__process_expired_transactions__incomplete_transaction',
-            array('EED_Ticket_Sales_Monitor', 'process_abandoned_transactions'),
-            10,
-            1
-        );
-        add_action(
-            'AHEE__EE_Cron_Tasks__process_expired_transactions__failed_transaction',
-            array('EED_Ticket_Sales_Monitor', 'process_failed_transactions'),
-            10,
-            1
-        );
-    }
-
-
-    /**
-     * set_hooks_admin - for hooking into EE Admin Core, other modules, etc
-     *
-     * @return void
-     */
-    public static function set_hooks_admin()
-    {
-        EED_Ticket_Sales_Monitor::set_hooks();
-    }
-
-
-    /**
-     * @return EED_Ticket_Sales_Monitor|EED_Module
-     */
-    public static function instance()
-    {
-        return parent::get_instance(__CLASS__);
-    }
-
-
-    /**
-     * @param WP_Query $WP_Query
-     * @return    void
-     */
-    public function run($WP_Query)
-    {
-    }
-
-
-
-    /********************************** PRE_TICKET_SALES  **********************************/
-
-
-    /**
-     * Retrieves grand totals from the line items that have no TXN ID
-     * and timestamps less than the current time minus the session lifespan.
-     * These are carts that have been abandoned before the "registrant" even attempted to checkout.
-     * We're going to release the tickets for these line items before attempting to add more to the cart.
-     *
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws UnexpectedEntityException
-     */
-    public static function release_tickets_for_expired_carts()
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
-        }
-        do_action('AHEE__EED_Ticket_Sales_Monitor__release_tickets_for_expired_carts__begin');
-        $expired_ticket_IDs = array();
-        /** @var EventEspresso\core\domain\values\session\SessionLifespan $session_lifespan */
-        $session_lifespan = LoaderFactory::getLoader()->getShared(
-            'EventEspresso\core\domain\values\session\SessionLifespan'
-        );
-        $timestamp = $session_lifespan->expiration();
-        $expired_ticket_line_items = EEM_Line_Item::instance()->getTicketLineItemsForExpiredCarts($timestamp);
-        if (self::debug) {
-            echo self::$nl . ' . time(): ' . time();
-            echo self::$nl . ' . time() as date: ' . date('Y-m-d H:i a');
-            echo self::$nl . ' . session expiration: ' . $session_lifespan->expiration();
-            echo self::$nl . ' . session expiration as date: ' . date('Y-m-d H:i a', $session_lifespan->expiration());
-            echo self::$nl . ' . timestamp: ' . $timestamp;
-            echo self::$nl . ' . $expired_ticket_line_items: ' . count($expired_ticket_line_items);
-        }
-        if (! empty($expired_ticket_line_items)) {
-            foreach ($expired_ticket_line_items as $expired_ticket_line_item) {
-                if (! $expired_ticket_line_item instanceof EE_Line_Item) {
-                    continue;
-                }
-                $expired_ticket_IDs[ $expired_ticket_line_item->OBJ_ID() ] = $expired_ticket_line_item->OBJ_ID();
-                if (self::debug) {
-                    echo self::$nl . ' . $expired_ticket_line_item->OBJ_ID(): ' . $expired_ticket_line_item->OBJ_ID();
-                    echo self::$nl . ' . $expired_ticket_line_item->timestamp(): '
-                         . date(
-                             'Y-m-d h:i a',
-                             $expired_ticket_line_item->timestamp(true)
-                         );
-                }
-            }
-            if (! empty($expired_ticket_IDs)) {
-                EED_Ticket_Sales_Monitor::release_reservations_for_tickets(
-                    \EEM_Ticket::instance()->get_tickets_with_IDs($expired_ticket_IDs),
-                    array(),
-                    __FUNCTION__
-                );
-                // now  let's get rid of expired line items so that they can't interfere with tracking
-                EED_Ticket_Sales_Monitor::clear_expired_line_items_with_no_transaction($timestamp);
-            }
-        }
-        do_action(
-            'AHEE__EED_Ticket_Sales_Monitor__release_tickets_for_expired_carts__end',
-            $expired_ticket_IDs,
-            $expired_ticket_line_items
-        );
-    }
-
-
-
-    /********************************** VALIDATE_TICKET_SALE  **********************************/
-
-
-    /**
-     * callback for 'FHEE__EED_Ticket_Selector__process_ticket_selections__valid_post_data'
-     *
-     * @param int       $qty
-     * @param EE_Ticket $ticket
-     * @return bool
-     * @throws UnexpectedEntityException
-     * @throws EE_Error
-     */
-    public static function validate_ticket_sale($qty = 1, EE_Ticket $ticket)
-    {
-        $qty = absint($qty);
-        if ($qty > 0) {
-            $qty = EED_Ticket_Sales_Monitor::instance()->_validate_ticket_sale($ticket, $qty);
-        }
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
-            echo self::$nl . self::$nl . '<b> RETURNED QTY: ' . $qty . '</b>';
-        }
-        return $qty;
-    }
-
-
-    /**
-     * checks whether an individual ticket is available for purchase based on datetime, and ticket details
-     *
-     * @param   EE_Ticket $ticket
-     * @param int         $qty
-     * @return int
-     * @throws UnexpectedEntityException
-     * @throws EE_Error
-     */
-    protected function _validate_ticket_sale(EE_Ticket $ticket, $qty = 1)
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-        }
-        if (! $ticket instanceof EE_Ticket) {
-            return 0;
-        }
-        if (self::debug) {
-            echo self::$nl . '<b> . ticket->ID: ' . $ticket->ID() . '</b>';
-            echo self::$nl . ' . original ticket->reserved: ' . $ticket->reserved();
-        }
-        $ticket->refresh_from_db();
-        // first let's determine the ticket availability based on sales
-        $available = $ticket->qty('saleable');
-        if (self::debug) {
-            echo self::$nl . ' . . . ticket->qty: ' . $ticket->qty();
-            echo self::$nl . ' . . . ticket->sold: ' . $ticket->sold();
-            echo self::$nl . ' . . . ticket->reserved: ' . $ticket->reserved();
-            echo self::$nl . ' . . . ticket->qty(saleable): ' . $ticket->qty('saleable');
-            echo self::$nl . ' . . . available: ' . $available;
-        }
-        if ($available < 1) {
-            $this->_ticket_sold_out($ticket);
-            return 0;
-        }
-        if (self::debug) {
-            echo self::$nl . ' . . . qty: ' . $qty;
-        }
-        if ($available < $qty) {
-            $qty = $available;
-            if (self::debug) {
-                echo self::$nl . ' . . . QTY ADJUSTED: ' . $qty;
-            }
-            $this->_ticket_quantity_decremented($ticket);
-        }
-        if ($this->_reserve_ticket($ticket, $qty)) {
-            return $qty;
-        } else {
-            return 0;
-        }
-    }
-
-
-    /**
-     * increments ticket reserved based on quantity passed
-     *
-     * @param    EE_Ticket $ticket
-     * @param int          $quantity
-     * @return bool indicating success or failure
-     * @throws EE_Error
-     */
-    protected function _reserve_ticket(EE_Ticket $ticket, $quantity = 1)
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . ' . . . INCREASE RESERVED: ' . $quantity;
-        }
-        return $ticket->increaseReserved($quantity, 'TicketSalesMonitor:' . __LINE__);
-    }
-
-
-    /**
-     * @param  EE_Ticket $ticket
-     * @param  int       $quantity
-     * @return bool
-     * @throws EE_Error
-     */
-    protected function _release_reserved_ticket(EE_Ticket $ticket, $quantity = 1)
-    {
-        if (self::debug) {
-            echo self::$nl . ' . . . ticket->ID: ' . $ticket->ID();
-            echo self::$nl . ' . . . ticket->reserved before: ' . $ticket->reserved();
-        }
-        $ticket->decreaseReserved($quantity, true, 'TicketSalesMonitor:' . __LINE__);
-        if (self::debug) {
-            echo self::$nl . ' . . . ticket->reserved after: ' . $ticket->reserved();
-        }
-        return $ticket->save() ? 1 : 0;
-    }
-
-
-    /**
-     * removes quantities within the ticket selector based on zero ticket availability
-     *
-     * @param    EE_Ticket $ticket
-     * @return    void
-     * @throws UnexpectedEntityException
-     * @throws EE_Error
-     */
-    protected function _ticket_sold_out(EE_Ticket $ticket)
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-            echo self::$nl . ' . . ticket->name: ' . $this->_get_ticket_and_event_name($ticket);
-        }
-        $this->sold_out_tickets[] = $this->_get_ticket_and_event_name($ticket);
-    }
-
-
-    /**
-     * adjusts quantities within the ticket selector based on decreased ticket availability
-     *
-     * @param    EE_Ticket $ticket
-     * @return void
-     * @throws UnexpectedEntityException
-     * @throws EE_Error
-     */
-    protected function _ticket_quantity_decremented(EE_Ticket $ticket)
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-            echo self::$nl . ' . . ticket->name: ' . $this->_get_ticket_and_event_name($ticket);
-        }
-        $this->decremented_tickets[] = $this->_get_ticket_and_event_name($ticket);
-    }
-
-
-    /**
-     * builds string out of ticket and event name
-     *
-     * @param    EE_Ticket $ticket
-     * @return string
-     * @throws UnexpectedEntityException
-     * @throws EE_Error
-     */
-    protected function _get_ticket_and_event_name(EE_Ticket $ticket)
-    {
-        $event = $ticket->get_related_event();
-        if ($event instanceof EE_Event) {
-            $ticket_name = sprintf(
-                _x('%1$s for %2$s', 'ticket name for event name', 'event_espresso'),
-                $ticket->name(),
-                $event->name()
-            );
-        } else {
-            $ticket_name = $ticket->name();
-        }
-        return $ticket_name;
-    }
-
-
-
-    /********************************** EVENT CART  **********************************/
-
-
-    /**
-     * releases or reserves ticket(s) based on quantity passed
-     *
-     * @param  EE_Line_Item $line_item
-     * @param  int          $quantity
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public static function ticket_quantity_updated(EE_Line_Item $line_item, $quantity = 1)
-    {
-        $ticket = EEM_Ticket::instance()->get_one_by_ID(absint($line_item->OBJ_ID()));
-        if ($ticket instanceof EE_Ticket) {
-            $ticket->add_extra_meta(
-                EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-                __LINE__ . ') ' . __METHOD__ . '()'
-            );
-            if ($quantity > 0) {
-                EED_Ticket_Sales_Monitor::instance()->_reserve_ticket($ticket, $quantity);
-            } else {
-                EED_Ticket_Sales_Monitor::instance()->_release_reserved_ticket($ticket, $quantity);
-            }
-        }
-    }
-
-
-    /**
-     * releases reserved ticket(s) based on quantity passed
-     *
-     * @param  EE_Ticket $ticket
-     * @param  int       $quantity
-     * @return void
-     * @throws EE_Error
-     */
-    public static function ticket_removed_from_cart(EE_Ticket $ticket, $quantity = 1)
-    {
-        $ticket->add_extra_meta(
-            EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-            __LINE__ . ') ' . __METHOD__ . '()'
-        );
-        EED_Ticket_Sales_Monitor::instance()->_release_reserved_ticket($ticket, $quantity);
-    }
-
-
-
-    /********************************** POST_NOTICES  **********************************/
-
-
-    /**
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public static function post_notices()
-    {
-        EED_Ticket_Sales_Monitor::instance()->_post_notices();
-    }
-
-
-    /**
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _post_notices()
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-        }
-        $refresh_msg = '';
-        $none_added_msg = '';
-        if (defined('DOING_AJAX') && DOING_AJAX) {
-            $refresh_msg = __(
-                'Please refresh the page to view updated ticket quantities.',
-                'event_espresso'
-            );
-            $none_added_msg = __('No tickets were added for the event.', 'event_espresso');
-        }
-        if (! empty($this->sold_out_tickets)) {
-            EE_Error::add_attention(
-                sprintf(
-                    apply_filters(
-                        'FHEE__EED_Ticket_Sales_Monitor___post_notices__sold_out_tickets_notice',
-                        __(
-                            'We\'re sorry...%1$sThe following items have sold out since you first viewed this page, and can no longer be registered for:%1$s%1$s%2$s%1$s%1$sPlease note that availability can change at any time due to cancellations, so please check back again later if registration for this event(s) is important to you.%1$s%1$s%3$s%1$s%4$s%1$s',
-                            'event_espresso'
-                        )
-                    ),
-                    '<br />',
-                    implode('<br />', $this->sold_out_tickets),
-                    $none_added_msg,
-                    $refresh_msg
-                )
-            );
-            // alter code flow in the Ticket Selector for better UX
-            add_filter('FHEE__EED_Ticket_Selector__process_ticket_selections__tckts_slctd', '__return_true');
-            add_filter('FHEE__EED_Ticket_Selector__process_ticket_selections__success', '__return_false');
-            $this->sold_out_tickets = array();
-            // and reset the cart
-            EED_Ticket_Sales_Monitor::session_cart_reset(EE_Registry::instance()->SSN);
-        }
-        if (! empty($this->decremented_tickets)) {
-            EE_Error::add_attention(
-                sprintf(
-                    apply_filters(
-                        'FHEE__EED_Ticket_Sales_Monitor___ticket_quantity_decremented__notice',
-                        __(
-                            'We\'re sorry...%1$sDue to sales that have occurred since you first viewed the last page, the following items have had their quantities adjusted to match the current available amount:%1$s%1$s%2$s%1$s%1$sPlease note that availability can change at any time due to cancellations, so please check back again later if registration for this event(s) is important to you.%1$s%1$s%3$s%1$s%4$s%1$s',
-                            'event_espresso'
-                        )
-                    ),
-                    '<br />',
-                    implode('<br />', $this->decremented_tickets),
-                    $none_added_msg,
-                    $refresh_msg
-                )
-            );
-            $this->decremented_tickets = array();
-        }
-    }
-
-
-
-    /********************************** RELEASE_ALL_RESERVED_TICKETS_FOR_TRANSACTION  **********************************/
-
-
-    /**
-     * releases reserved tickets for all registrations of an EE_Transaction
-     * by default, will NOT release tickets for finalized transactions
-     *
-     * @param    EE_Transaction $transaction
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidSessionDataException
-     */
-    protected function _release_all_reserved_tickets_for_transaction(EE_Transaction $transaction)
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-            echo self::$nl . ' . transaction->ID: ' . $transaction->ID();
-            echo self::$nl . ' . TXN status_ID: ' . $transaction->status_ID();
-        }
-        // check if 'finalize_registration' step has been completed...
-        $finalized = $transaction->reg_step_completed('finalize_registration');
-        if (self::debug) {
-            // DEBUG LOG
-            EEH_Debug_Tools::log(
-                __CLASS__,
-                __FUNCTION__,
-                __LINE__,
-                array('finalized' => $finalized),
-                false,
-                'EE_Transaction: ' . $transaction->ID()
-            );
-        }
-        // how many tickets were released
-        $count = 0;
-        if (self::debug) {
-            echo self::$nl . ' . . . TXN finalized: ' . $finalized;
-        }
-        $release_tickets_with_TXN_status = array(
-            EEM_Transaction::failed_status_code,
-            EEM_Transaction::abandoned_status_code,
-            EEM_Transaction::incomplete_status_code,
-        );
-        $events = array();
-        // if the session is getting cleared BEFORE the TXN has been finalized or the transaction is not completed
-        if (! $finalized || in_array($transaction->status_ID(), $release_tickets_with_TXN_status, true)) {
-            // cancel any reserved tickets for registrations that were not approved
-            $registrations = $transaction->registrations();
-            if (self::debug) {
-                echo self::$nl . ' . . . # registrations: ' . count($registrations);
-                $reg = reset($registrations);
-                $ticket = $reg->ticket();
-                if ($ticket instanceof EE_Ticket) {
-                    $ticket->add_extra_meta(
-                        EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-                        __LINE__ . ') Release All Tickets TXN:' . $transaction->ID()
-                    );
-                }
-            }
-            if (! empty($registrations)) {
-                foreach ($registrations as $registration) {
-                    if ($registration instanceof EE_Registration
-                        && $this->_release_reserved_ticket_for_registration($registration, $transaction)
-                    ) {
-                        $count++;
-                        $events[ $registration->event_ID() ] = $registration->event();
-                    }
-                }
-            }
-        }
-        if ($events !== array()) {
-            foreach ($events as $event) {
-                /** @var EE_Event $event */
-                $event->perform_sold_out_status_check();
-            }
-        }
-        return $count;
-    }
-
-
-    /**
-     * releases reserved tickets for an EE_Registration
-     * by default, will NOT release tickets for APPROVED registrations
-     *
-     * @param EE_Registration $registration
-     * @param EE_Transaction  $transaction
-     * @return int
-     * @throws EE_Error
-     */
-    protected function _release_reserved_ticket_for_registration(
-        EE_Registration $registration,
-        EE_Transaction $transaction
-    ) {
-        $STS_ID = $transaction->status_ID();
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-            echo self::$nl . ' . . registration->ID: ' . $registration->ID();
-            echo self::$nl . ' . . registration->status_ID: ' . $registration->status_ID();
-            echo self::$nl . ' . . transaction->status_ID(): ' . $STS_ID;
-        }
-        if (// release Tickets for Failed Transactions and Abandoned Transactions
-            $STS_ID === EEM_Transaction::failed_status_code
-            || $STS_ID === EEM_Transaction::abandoned_status_code
-            || (
-                // also release Tickets for Incomplete Transactions, but ONLY if the Registrations are NOT Approved
-                $STS_ID === EEM_Transaction::incomplete_status_code
-                && $registration->status_ID() !== EEM_Registration::status_id_approved
-            )
-        ) {
-            if (self::debug) {
-                echo self::$nl . self::$nl . ' . . RELEASE RESERVED TICKET';
-                $rsrvd = $registration->get_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true);
-                echo self::$nl . ' . . . registration HAS_RESERVED_TICKET_KEY: ';
-                var_dump($rsrvd);
-            }
-            $registration->release_reserved_ticket(true, 'TicketSalesMonitor:' . __LINE__);
-            return 1;
-        }
-        return 0;
-    }
-
-
-
-    /********************************** SESSION_CART_RESET  **********************************/
-
-
-    /**
-     * callback hooked into 'AHEE__EE_Session__reset_cart__before_reset'
-     *
-     * @param EE_Session $session
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public static function session_cart_reset(EE_Session $session)
-    {
-        // don't release tickets if checkout was already reset
-        if (did_action('AHEE__EE_Session__reset_checkout__before_reset')) {
-            return;
-        }
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-        }
-        // first check of the session has a valid Checkout object
-        $checkout = $session->checkout();
-        if ($checkout instanceof EE_Checkout) {
-            // and use that to clear ticket reservations because it will update the associated registration meta data
-            EED_Ticket_Sales_Monitor::instance()->_session_checkout_reset($checkout);
-            return;
-        }
-        $cart = $session->cart();
-        if ($cart instanceof EE_Cart) {
-            if (self::debug) {
-                echo self::$nl . self::$nl . ' cart instance of EE_Cart: ';
-            }
-            EED_Ticket_Sales_Monitor::instance()->_session_cart_reset($cart, $session);
-        } else {
-            if (self::debug) {
-                echo self::$nl . self::$nl . ' invalid EE_Cart: ';
-                var_export($cart, true);
-            }
-        }
-    }
-
-
-    /**
-     * releases reserved tickets in the EE_Cart
-     *
-     * @param EE_Cart $cart
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _session_cart_reset(EE_Cart $cart, EE_Session $session)
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-        }
-        $ticket_line_items = $cart->get_tickets();
-        if (empty($ticket_line_items)) {
-            return;
-        }
-        if (self::debug) {
-            echo '<br /> . ticket_line_item count: ' . count($ticket_line_items);
-        }
-        foreach ($ticket_line_items as $ticket_line_item) {
-            if (self::debug) {
-                echo self::$nl . ' . ticket_line_item->ID(): ' . $ticket_line_item->ID();
-            }
-            if ($ticket_line_item instanceof EE_Line_Item && $ticket_line_item->OBJ_type() === 'Ticket') {
-                if (self::debug) {
-                    echo self::$nl . ' . . ticket_line_item->OBJ_ID(): ' . $ticket_line_item->OBJ_ID();
-                }
-                $ticket = EEM_Ticket::instance()->get_one_by_ID($ticket_line_item->OBJ_ID());
-                if ($ticket instanceof EE_Ticket) {
-                    if (self::debug) {
-                        echo self::$nl . ' . . ticket->ID(): ' . $ticket->ID();
-                        echo self::$nl . ' . . ticket_line_item->quantity(): ' . $ticket_line_item->quantity();
-                    }
-                    $ticket->add_extra_meta(
-                        EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-                        __LINE__ . ') ' . __METHOD__ . '() SID = ' . $session->id()
-                    );
-                    $this->_release_reserved_ticket($ticket, $ticket_line_item->quantity());
-                }
-            }
-        }
-        if (self::debug) {
-            echo self::$nl . self::$nl . ' RESET COMPLETED ';
-        }
-    }
-
-
-
-    /********************************** SESSION_CHECKOUT_RESET  **********************************/
-
-
-    /**
-     * callback hooked into 'AHEE__EE_Session__reset_checkout__before_reset'
-     *
-     * @param EE_Session $session
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidSessionDataException
-     */
-    public static function session_checkout_reset(EE_Session $session)
-    {
-        // don't release tickets if cart was already reset
-        if (did_action('AHEE__EE_Session__reset_cart__before_reset')) {
-            return;
-        }
-        $checkout = $session->checkout();
-        if ($checkout instanceof EE_Checkout) {
-            EED_Ticket_Sales_Monitor::instance()->_session_checkout_reset($checkout);
-        }
-    }
-
-
-    /**
-     * releases reserved tickets for the EE_Checkout->transaction
-     *
-     * @param EE_Checkout $checkout
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidSessionDataException
-     */
-    protected function _session_checkout_reset(EE_Checkout $checkout)
-    {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-        }
-        // we want to release the each registration's reserved tickets if the session was cleared, but not if this is a revisit
-        if ($checkout->revisit || ! $checkout->transaction instanceof EE_Transaction) {
-            return;
-        }
-        $this->_release_all_reserved_tickets_for_transaction($checkout->transaction);
-    }
-
-
-
-    /********************************** SESSION_EXPIRED_RESET  **********************************/
-
-
-    /**
-     * @param    EE_Session $session
-     * @return    void
-     */
-    public static function session_expired_reset(EE_Session $session)
-    {
-    }
-
-
-
-    /********************************** PROCESS_ABANDONED_TRANSACTIONS  **********************************/
-
-
-    /**
-     * releases reserved tickets for all registrations of an ABANDONED EE_Transaction
-     * by default, will NOT release tickets for free transactions, or any that have received a payment
-     *
-     * @param EE_Transaction $transaction
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidSessionDataException
-     */
-    public static function process_abandoned_transactions(EE_Transaction $transaction)
-    {
-        // is this TXN free or has any money been paid towards this TXN? If so, then leave it alone
-        if ($transaction->is_free() || $transaction->paid() > 0) {
-            if (self::debug) {
-                // DEBUG LOG
-                EEH_Debug_Tools::log(
-                    __CLASS__,
-                    __FUNCTION__,
-                    __LINE__,
-                    array($transaction),
-                    false,
-                    'EE_Transaction: ' . $transaction->ID()
-                );
-            }
-            return;
-        }
-        // have their been any successful payments made ?
-        $payments = $transaction->payments();
-        foreach ($payments as $payment) {
-            if ($payment instanceof EE_Payment && $payment->status() === EEM_Payment::status_id_approved) {
-                if (self::debug) {
-                    // DEBUG LOG
-                    EEH_Debug_Tools::log(
-                        __CLASS__,
-                        __FUNCTION__,
-                        __LINE__,
-                        array($payment),
-                        false,
-                        'EE_Transaction: ' . $transaction->ID()
-                    );
-                }
-                return;
-            }
-        }
-        // since you haven't even attempted to pay for your ticket...
-        EED_Ticket_Sales_Monitor::instance()->_release_all_reserved_tickets_for_transaction($transaction);
-    }
-
-
-
-    /********************************** PROCESS_FAILED_TRANSACTIONS  **********************************/
-
-
-    /**
-     * releases reserved tickets for absolutely ALL registrations of a FAILED EE_Transaction
-     *
-     * @param EE_Transaction $transaction
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidSessionDataException
-     */
-    public static function process_failed_transactions(EE_Transaction $transaction)
-    {
-        // since you haven't even attempted to pay for your ticket...
-        EED_Ticket_Sales_Monitor::instance()->_release_all_reserved_tickets_for_transaction($transaction);
-    }
-
-
-
-    /********************************** RESET RESERVATION COUNTS  *********************************/
-
-
-    /**
-     * Resets all ticket and datetime reserved counts to zero
-     * Tickets that are currently associated with a Transaction that is in progress
-     *
-     * @throws EE_Error
-     * @throws DomainException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws InvalidArgumentException
-     * @throws UnexpectedEntityException
-     */
-    public static function reset_reservation_counts()
-    {
-        /** @var EE_Line_Item[] $valid_reserved_tickets */
-        $valid_reserved_tickets = array();
-        /** @var EE_Transaction[] $transactions_not_in_progress */
-        $transactions_not_in_progress = EEM_Transaction::instance()->get_transactions_not_in_progress();
-        foreach ($transactions_not_in_progress as $transaction) {
-            // if this TXN has been fully completed, then skip it
-            if ($transaction->reg_step_completed('finalize_registration')) {
-                continue;
-            }
-            $total_line_item = $transaction->total_line_item();
-            // $transaction_in_progress->line
-            if (! $total_line_item instanceof EE_Line_Item) {
-                throw new DomainException(
-                    esc_html__(
-                        'Transaction does not have a valid Total Line Item associated with it.',
-                        'event_espresso'
-                    )
-                );
-            }
-            $valid_reserved_tickets += EED_Ticket_Sales_Monitor::get_ticket_line_items_for_grand_total(
-                $total_line_item
-            );
-        }
-        $total_line_items = EEM_Line_Item::instance()->get_total_line_items_for_active_carts();
-        foreach ($total_line_items as $total_line_item) {
-            $valid_reserved_tickets += EED_Ticket_Sales_Monitor::get_ticket_line_items_for_grand_total(
-                $total_line_item
-            );
-        }
-        $tickets_with_reservations = EEM_Ticket::instance()->get_tickets_with_reservations();
-        return EED_Ticket_Sales_Monitor::release_reservations_for_tickets(
-            $tickets_with_reservations,
-            $valid_reserved_tickets,
-            __FUNCTION__
-        );
-    }
-
-
-    /**
-     * @param EE_Line_Item $total_line_item
-     * @return EE_Line_Item[]
-     */
-    private static function get_ticket_line_items_for_grand_total(EE_Line_Item $total_line_item)
-    {
-        /** @var EE_Line_Item[] $valid_reserved_tickets */
-        $valid_reserved_tickets = array();
-        $ticket_line_items = EEH_Line_Item::get_ticket_line_items($total_line_item);
-        foreach ($ticket_line_items as $ticket_line_item) {
-            if ($ticket_line_item instanceof EE_Line_Item) {
-                $valid_reserved_tickets[] = $ticket_line_item;
-            }
-        }
-        return $valid_reserved_tickets;
-    }
-
-
-    /**
-     * @param EE_Ticket[]    $tickets_with_reservations
-     * @param EE_Line_Item[] $valid_reserved_ticket_line_items
-     * @return int
-     * @throws UnexpectedEntityException
-     * @throws DomainException
-     * @throws EE_Error
-     */
-    private static function release_reservations_for_tickets(
-        array $tickets_with_reservations,
-        array $valid_reserved_ticket_line_items = array(),
-        $source
-    ) {
-        if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
-        }
-        $total_tickets_released = 0;
-        $sold_out_events = array();
-        foreach ($tickets_with_reservations as $ticket_with_reservations) {
-            if (! $ticket_with_reservations instanceof EE_Ticket) {
-                continue;
-            }
-            $reserved_qty = $ticket_with_reservations->reserved();
-            if (self::debug) {
-                echo self::$nl . ' . $ticket_with_reservations->ID(): ' . $ticket_with_reservations->ID();
-                echo self::$nl . ' . $reserved_qty: ' . $reserved_qty;
-            }
-            foreach ($valid_reserved_ticket_line_items as $valid_reserved_ticket_line_item) {
-                if ($valid_reserved_ticket_line_item instanceof EE_Line_Item
-                    && $valid_reserved_ticket_line_item->OBJ_ID() === $ticket_with_reservations->ID()
-                ) {
-                    if (self::debug) {
-                        echo self::$nl . ' . $valid_reserved_ticket_line_item->quantity(): '
-                             . $valid_reserved_ticket_line_item->quantity();
-                    }
-                    $reserved_qty -= $valid_reserved_ticket_line_item->quantity();
-                }
-            }
-            if ($reserved_qty > 0) {
-                $ticket_with_reservations->add_extra_meta(
-                    EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-                    __LINE__ . ') ' . $source . '()'
-                );
-                $ticket_with_reservations->decreaseReserved($reserved_qty, true, 'TicketSalesMonitor:' . __LINE__);
-                $ticket_with_reservations->save();
-                $total_tickets_released += $reserved_qty;
-                $event = $ticket_with_reservations->get_related_event();
-                // track sold out events
-                if ($event instanceof EE_Event && $event->is_sold_out()) {
-                    $sold_out_events[] = $event;
-                }
-            }
-        }
-        if (self::debug) {
-            echo self::$nl . ' . $total_tickets_released: ' . $total_tickets_released;
-        }
-        // double check whether sold out events should remain sold out after releasing tickets
-        if ($sold_out_events !== array()) {
-            foreach ($sold_out_events as $sold_out_event) {
-                /** @var EE_Event $sold_out_event */
-                $sold_out_event->perform_sold_out_status_check();
-            }
-        }
-        return $total_tickets_released;
-    }
-
-
-
-    /********************************** SHUTDOWN  **********************************/
-
-
-    /**
-     * @param int $timestamp
-     * @return false|int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public static function clear_expired_line_items_with_no_transaction($timestamp = 0)
-    {
-        /** @type WPDB $wpdb */
-        global $wpdb;
-        if (! absint($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 $wpdb->query(
-            $wpdb->prepare(
-                'DELETE FROM ' . EEM_Line_Item::instance()->table() . '
+	const debug = false;
+
+	private static $nl = '';
+
+	/**
+	 * an array of raw ticket data from EED_Ticket_Selector
+	 *
+	 * @var array $ticket_selections
+	 */
+	protected $ticket_selections = array();
+
+	/**
+	 * the raw ticket data from EED_Ticket_Selector is organized in rows
+	 * according to how they are displayed in the actual Ticket_Selector
+	 * this tracks the current row being processed
+	 *
+	 * @var int $current_row
+	 */
+	protected $current_row = 0;
+
+	/**
+	 * an array for tracking names of tickets that have sold out
+	 *
+	 * @var array $sold_out_tickets
+	 */
+	protected $sold_out_tickets = array();
+
+	/**
+	 * an array for tracking names of tickets that have had their quantities reduced
+	 *
+	 * @var array $decremented_tickets
+	 */
+	protected $decremented_tickets = array();
+
+
+	/**
+	 * set_hooks - for hooking into EE Core, other modules, etc
+	 *
+	 * @return    void
+	 */
+	public static function set_hooks()
+	{
+		self::$nl = defined('EE_TESTS_DIR') ? "\n" : '<br />';
+		// release tickets for expired carts
+		add_action(
+			'EED_Ticket_Selector__process_ticket_selections__before',
+			array('EED_Ticket_Sales_Monitor', 'release_tickets_for_expired_carts'),
+			1
+		);
+		// check ticket reserves AFTER MER does it's check (hence priority 20)
+		add_filter(
+			'FHEE__EE_Ticket_Selector___add_ticket_to_cart__ticket_qty',
+			array('EED_Ticket_Sales_Monitor', 'validate_ticket_sale'),
+			20,
+			3
+		);
+		// add notices for sold out tickets
+		add_action(
+			'AHEE__EE_Ticket_Selector__process_ticket_selections__after_tickets_added_to_cart',
+			array('EED_Ticket_Sales_Monitor', 'post_notices'),
+			10
+		);
+
+		// handle tickets deleted from cart
+		add_action(
+			'FHEE__EED_Multi_Event_Registration__delete_ticket__ticket_removed_from_cart',
+			array('EED_Ticket_Sales_Monitor', 'ticket_removed_from_cart'),
+			10,
+			2
+		);
+		// handle emptied carts
+		add_action(
+			'AHEE__EE_Session__reset_cart__before_reset',
+			array('EED_Ticket_Sales_Monitor', 'session_cart_reset'),
+			10,
+			1
+		);
+		add_action(
+			'AHEE__EED_Multi_Event_Registration__empty_event_cart__before_delete_cart',
+			array('EED_Ticket_Sales_Monitor', 'session_cart_reset'),
+			10,
+			1
+		);
+		// handle cancelled registrations
+		add_action(
+			'AHEE__EE_Session__reset_checkout__before_reset',
+			array('EED_Ticket_Sales_Monitor', 'session_checkout_reset'),
+			10,
+			1
+		);
+		// cron tasks
+		add_action(
+			'AHEE__EE_Cron_Tasks__process_expired_transactions__abandoned_transaction',
+			array('EED_Ticket_Sales_Monitor', 'process_abandoned_transactions'),
+			10,
+			1
+		);
+		add_action(
+			'AHEE__EE_Cron_Tasks__process_expired_transactions__incomplete_transaction',
+			array('EED_Ticket_Sales_Monitor', 'process_abandoned_transactions'),
+			10,
+			1
+		);
+		add_action(
+			'AHEE__EE_Cron_Tasks__process_expired_transactions__failed_transaction',
+			array('EED_Ticket_Sales_Monitor', 'process_failed_transactions'),
+			10,
+			1
+		);
+	}
+
+
+	/**
+	 * set_hooks_admin - for hooking into EE Admin Core, other modules, etc
+	 *
+	 * @return void
+	 */
+	public static function set_hooks_admin()
+	{
+		EED_Ticket_Sales_Monitor::set_hooks();
+	}
+
+
+	/**
+	 * @return EED_Ticket_Sales_Monitor|EED_Module
+	 */
+	public static function instance()
+	{
+		return parent::get_instance(__CLASS__);
+	}
+
+
+	/**
+	 * @param WP_Query $WP_Query
+	 * @return    void
+	 */
+	public function run($WP_Query)
+	{
+	}
+
+
+
+	/********************************** PRE_TICKET_SALES  **********************************/
+
+
+	/**
+	 * Retrieves grand totals from the line items that have no TXN ID
+	 * and timestamps less than the current time minus the session lifespan.
+	 * These are carts that have been abandoned before the "registrant" even attempted to checkout.
+	 * We're going to release the tickets for these line items before attempting to add more to the cart.
+	 *
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws UnexpectedEntityException
+	 */
+	public static function release_tickets_for_expired_carts()
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
+		}
+		do_action('AHEE__EED_Ticket_Sales_Monitor__release_tickets_for_expired_carts__begin');
+		$expired_ticket_IDs = array();
+		/** @var EventEspresso\core\domain\values\session\SessionLifespan $session_lifespan */
+		$session_lifespan = LoaderFactory::getLoader()->getShared(
+			'EventEspresso\core\domain\values\session\SessionLifespan'
+		);
+		$timestamp = $session_lifespan->expiration();
+		$expired_ticket_line_items = EEM_Line_Item::instance()->getTicketLineItemsForExpiredCarts($timestamp);
+		if (self::debug) {
+			echo self::$nl . ' . time(): ' . time();
+			echo self::$nl . ' . time() as date: ' . date('Y-m-d H:i a');
+			echo self::$nl . ' . session expiration: ' . $session_lifespan->expiration();
+			echo self::$nl . ' . session expiration as date: ' . date('Y-m-d H:i a', $session_lifespan->expiration());
+			echo self::$nl . ' . timestamp: ' . $timestamp;
+			echo self::$nl . ' . $expired_ticket_line_items: ' . count($expired_ticket_line_items);
+		}
+		if (! empty($expired_ticket_line_items)) {
+			foreach ($expired_ticket_line_items as $expired_ticket_line_item) {
+				if (! $expired_ticket_line_item instanceof EE_Line_Item) {
+					continue;
+				}
+				$expired_ticket_IDs[ $expired_ticket_line_item->OBJ_ID() ] = $expired_ticket_line_item->OBJ_ID();
+				if (self::debug) {
+					echo self::$nl . ' . $expired_ticket_line_item->OBJ_ID(): ' . $expired_ticket_line_item->OBJ_ID();
+					echo self::$nl . ' . $expired_ticket_line_item->timestamp(): '
+						 . date(
+							 'Y-m-d h:i a',
+							 $expired_ticket_line_item->timestamp(true)
+						 );
+				}
+			}
+			if (! empty($expired_ticket_IDs)) {
+				EED_Ticket_Sales_Monitor::release_reservations_for_tickets(
+					\EEM_Ticket::instance()->get_tickets_with_IDs($expired_ticket_IDs),
+					array(),
+					__FUNCTION__
+				);
+				// now  let's get rid of expired line items so that they can't interfere with tracking
+				EED_Ticket_Sales_Monitor::clear_expired_line_items_with_no_transaction($timestamp);
+			}
+		}
+		do_action(
+			'AHEE__EED_Ticket_Sales_Monitor__release_tickets_for_expired_carts__end',
+			$expired_ticket_IDs,
+			$expired_ticket_line_items
+		);
+	}
+
+
+
+	/********************************** VALIDATE_TICKET_SALE  **********************************/
+
+
+	/**
+	 * callback for 'FHEE__EED_Ticket_Selector__process_ticket_selections__valid_post_data'
+	 *
+	 * @param int       $qty
+	 * @param EE_Ticket $ticket
+	 * @return bool
+	 * @throws UnexpectedEntityException
+	 * @throws EE_Error
+	 */
+	public static function validate_ticket_sale($qty = 1, EE_Ticket $ticket)
+	{
+		$qty = absint($qty);
+		if ($qty > 0) {
+			$qty = EED_Ticket_Sales_Monitor::instance()->_validate_ticket_sale($ticket, $qty);
+		}
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
+			echo self::$nl . self::$nl . '<b> RETURNED QTY: ' . $qty . '</b>';
+		}
+		return $qty;
+	}
+
+
+	/**
+	 * checks whether an individual ticket is available for purchase based on datetime, and ticket details
+	 *
+	 * @param   EE_Ticket $ticket
+	 * @param int         $qty
+	 * @return int
+	 * @throws UnexpectedEntityException
+	 * @throws EE_Error
+	 */
+	protected function _validate_ticket_sale(EE_Ticket $ticket, $qty = 1)
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+		}
+		if (! $ticket instanceof EE_Ticket) {
+			return 0;
+		}
+		if (self::debug) {
+			echo self::$nl . '<b> . ticket->ID: ' . $ticket->ID() . '</b>';
+			echo self::$nl . ' . original ticket->reserved: ' . $ticket->reserved();
+		}
+		$ticket->refresh_from_db();
+		// first let's determine the ticket availability based on sales
+		$available = $ticket->qty('saleable');
+		if (self::debug) {
+			echo self::$nl . ' . . . ticket->qty: ' . $ticket->qty();
+			echo self::$nl . ' . . . ticket->sold: ' . $ticket->sold();
+			echo self::$nl . ' . . . ticket->reserved: ' . $ticket->reserved();
+			echo self::$nl . ' . . . ticket->qty(saleable): ' . $ticket->qty('saleable');
+			echo self::$nl . ' . . . available: ' . $available;
+		}
+		if ($available < 1) {
+			$this->_ticket_sold_out($ticket);
+			return 0;
+		}
+		if (self::debug) {
+			echo self::$nl . ' . . . qty: ' . $qty;
+		}
+		if ($available < $qty) {
+			$qty = $available;
+			if (self::debug) {
+				echo self::$nl . ' . . . QTY ADJUSTED: ' . $qty;
+			}
+			$this->_ticket_quantity_decremented($ticket);
+		}
+		if ($this->_reserve_ticket($ticket, $qty)) {
+			return $qty;
+		} else {
+			return 0;
+		}
+	}
+
+
+	/**
+	 * increments ticket reserved based on quantity passed
+	 *
+	 * @param    EE_Ticket $ticket
+	 * @param int          $quantity
+	 * @return bool indicating success or failure
+	 * @throws EE_Error
+	 */
+	protected function _reserve_ticket(EE_Ticket $ticket, $quantity = 1)
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . ' . . . INCREASE RESERVED: ' . $quantity;
+		}
+		return $ticket->increaseReserved($quantity, 'TicketSalesMonitor:' . __LINE__);
+	}
+
+
+	/**
+	 * @param  EE_Ticket $ticket
+	 * @param  int       $quantity
+	 * @return bool
+	 * @throws EE_Error
+	 */
+	protected function _release_reserved_ticket(EE_Ticket $ticket, $quantity = 1)
+	{
+		if (self::debug) {
+			echo self::$nl . ' . . . ticket->ID: ' . $ticket->ID();
+			echo self::$nl . ' . . . ticket->reserved before: ' . $ticket->reserved();
+		}
+		$ticket->decreaseReserved($quantity, true, 'TicketSalesMonitor:' . __LINE__);
+		if (self::debug) {
+			echo self::$nl . ' . . . ticket->reserved after: ' . $ticket->reserved();
+		}
+		return $ticket->save() ? 1 : 0;
+	}
+
+
+	/**
+	 * removes quantities within the ticket selector based on zero ticket availability
+	 *
+	 * @param    EE_Ticket $ticket
+	 * @return    void
+	 * @throws UnexpectedEntityException
+	 * @throws EE_Error
+	 */
+	protected function _ticket_sold_out(EE_Ticket $ticket)
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+			echo self::$nl . ' . . ticket->name: ' . $this->_get_ticket_and_event_name($ticket);
+		}
+		$this->sold_out_tickets[] = $this->_get_ticket_and_event_name($ticket);
+	}
+
+
+	/**
+	 * adjusts quantities within the ticket selector based on decreased ticket availability
+	 *
+	 * @param    EE_Ticket $ticket
+	 * @return void
+	 * @throws UnexpectedEntityException
+	 * @throws EE_Error
+	 */
+	protected function _ticket_quantity_decremented(EE_Ticket $ticket)
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+			echo self::$nl . ' . . ticket->name: ' . $this->_get_ticket_and_event_name($ticket);
+		}
+		$this->decremented_tickets[] = $this->_get_ticket_and_event_name($ticket);
+	}
+
+
+	/**
+	 * builds string out of ticket and event name
+	 *
+	 * @param    EE_Ticket $ticket
+	 * @return string
+	 * @throws UnexpectedEntityException
+	 * @throws EE_Error
+	 */
+	protected function _get_ticket_and_event_name(EE_Ticket $ticket)
+	{
+		$event = $ticket->get_related_event();
+		if ($event instanceof EE_Event) {
+			$ticket_name = sprintf(
+				_x('%1$s for %2$s', 'ticket name for event name', 'event_espresso'),
+				$ticket->name(),
+				$event->name()
+			);
+		} else {
+			$ticket_name = $ticket->name();
+		}
+		return $ticket_name;
+	}
+
+
+
+	/********************************** EVENT CART  **********************************/
+
+
+	/**
+	 * releases or reserves ticket(s) based on quantity passed
+	 *
+	 * @param  EE_Line_Item $line_item
+	 * @param  int          $quantity
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public static function ticket_quantity_updated(EE_Line_Item $line_item, $quantity = 1)
+	{
+		$ticket = EEM_Ticket::instance()->get_one_by_ID(absint($line_item->OBJ_ID()));
+		if ($ticket instanceof EE_Ticket) {
+			$ticket->add_extra_meta(
+				EE_Ticket::META_KEY_TICKET_RESERVATIONS,
+				__LINE__ . ') ' . __METHOD__ . '()'
+			);
+			if ($quantity > 0) {
+				EED_Ticket_Sales_Monitor::instance()->_reserve_ticket($ticket, $quantity);
+			} else {
+				EED_Ticket_Sales_Monitor::instance()->_release_reserved_ticket($ticket, $quantity);
+			}
+		}
+	}
+
+
+	/**
+	 * releases reserved ticket(s) based on quantity passed
+	 *
+	 * @param  EE_Ticket $ticket
+	 * @param  int       $quantity
+	 * @return void
+	 * @throws EE_Error
+	 */
+	public static function ticket_removed_from_cart(EE_Ticket $ticket, $quantity = 1)
+	{
+		$ticket->add_extra_meta(
+			EE_Ticket::META_KEY_TICKET_RESERVATIONS,
+			__LINE__ . ') ' . __METHOD__ . '()'
+		);
+		EED_Ticket_Sales_Monitor::instance()->_release_reserved_ticket($ticket, $quantity);
+	}
+
+
+
+	/********************************** POST_NOTICES  **********************************/
+
+
+	/**
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public static function post_notices()
+	{
+		EED_Ticket_Sales_Monitor::instance()->_post_notices();
+	}
+
+
+	/**
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _post_notices()
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+		}
+		$refresh_msg = '';
+		$none_added_msg = '';
+		if (defined('DOING_AJAX') && DOING_AJAX) {
+			$refresh_msg = __(
+				'Please refresh the page to view updated ticket quantities.',
+				'event_espresso'
+			);
+			$none_added_msg = __('No tickets were added for the event.', 'event_espresso');
+		}
+		if (! empty($this->sold_out_tickets)) {
+			EE_Error::add_attention(
+				sprintf(
+					apply_filters(
+						'FHEE__EED_Ticket_Sales_Monitor___post_notices__sold_out_tickets_notice',
+						__(
+							'We\'re sorry...%1$sThe following items have sold out since you first viewed this page, and can no longer be registered for:%1$s%1$s%2$s%1$s%1$sPlease note that availability can change at any time due to cancellations, so please check back again later if registration for this event(s) is important to you.%1$s%1$s%3$s%1$s%4$s%1$s',
+							'event_espresso'
+						)
+					),
+					'<br />',
+					implode('<br />', $this->sold_out_tickets),
+					$none_added_msg,
+					$refresh_msg
+				)
+			);
+			// alter code flow in the Ticket Selector for better UX
+			add_filter('FHEE__EED_Ticket_Selector__process_ticket_selections__tckts_slctd', '__return_true');
+			add_filter('FHEE__EED_Ticket_Selector__process_ticket_selections__success', '__return_false');
+			$this->sold_out_tickets = array();
+			// and reset the cart
+			EED_Ticket_Sales_Monitor::session_cart_reset(EE_Registry::instance()->SSN);
+		}
+		if (! empty($this->decremented_tickets)) {
+			EE_Error::add_attention(
+				sprintf(
+					apply_filters(
+						'FHEE__EED_Ticket_Sales_Monitor___ticket_quantity_decremented__notice',
+						__(
+							'We\'re sorry...%1$sDue to sales that have occurred since you first viewed the last page, the following items have had their quantities adjusted to match the current available amount:%1$s%1$s%2$s%1$s%1$sPlease note that availability can change at any time due to cancellations, so please check back again later if registration for this event(s) is important to you.%1$s%1$s%3$s%1$s%4$s%1$s',
+							'event_espresso'
+						)
+					),
+					'<br />',
+					implode('<br />', $this->decremented_tickets),
+					$none_added_msg,
+					$refresh_msg
+				)
+			);
+			$this->decremented_tickets = array();
+		}
+	}
+
+
+
+	/********************************** RELEASE_ALL_RESERVED_TICKETS_FOR_TRANSACTION  **********************************/
+
+
+	/**
+	 * releases reserved tickets for all registrations of an EE_Transaction
+	 * by default, will NOT release tickets for finalized transactions
+	 *
+	 * @param    EE_Transaction $transaction
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidSessionDataException
+	 */
+	protected function _release_all_reserved_tickets_for_transaction(EE_Transaction $transaction)
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+			echo self::$nl . ' . transaction->ID: ' . $transaction->ID();
+			echo self::$nl . ' . TXN status_ID: ' . $transaction->status_ID();
+		}
+		// check if 'finalize_registration' step has been completed...
+		$finalized = $transaction->reg_step_completed('finalize_registration');
+		if (self::debug) {
+			// DEBUG LOG
+			EEH_Debug_Tools::log(
+				__CLASS__,
+				__FUNCTION__,
+				__LINE__,
+				array('finalized' => $finalized),
+				false,
+				'EE_Transaction: ' . $transaction->ID()
+			);
+		}
+		// how many tickets were released
+		$count = 0;
+		if (self::debug) {
+			echo self::$nl . ' . . . TXN finalized: ' . $finalized;
+		}
+		$release_tickets_with_TXN_status = array(
+			EEM_Transaction::failed_status_code,
+			EEM_Transaction::abandoned_status_code,
+			EEM_Transaction::incomplete_status_code,
+		);
+		$events = array();
+		// if the session is getting cleared BEFORE the TXN has been finalized or the transaction is not completed
+		if (! $finalized || in_array($transaction->status_ID(), $release_tickets_with_TXN_status, true)) {
+			// cancel any reserved tickets for registrations that were not approved
+			$registrations = $transaction->registrations();
+			if (self::debug) {
+				echo self::$nl . ' . . . # registrations: ' . count($registrations);
+				$reg = reset($registrations);
+				$ticket = $reg->ticket();
+				if ($ticket instanceof EE_Ticket) {
+					$ticket->add_extra_meta(
+						EE_Ticket::META_KEY_TICKET_RESERVATIONS,
+						__LINE__ . ') Release All Tickets TXN:' . $transaction->ID()
+					);
+				}
+			}
+			if (! empty($registrations)) {
+				foreach ($registrations as $registration) {
+					if ($registration instanceof EE_Registration
+						&& $this->_release_reserved_ticket_for_registration($registration, $transaction)
+					) {
+						$count++;
+						$events[ $registration->event_ID() ] = $registration->event();
+					}
+				}
+			}
+		}
+		if ($events !== array()) {
+			foreach ($events as $event) {
+				/** @var EE_Event $event */
+				$event->perform_sold_out_status_check();
+			}
+		}
+		return $count;
+	}
+
+
+	/**
+	 * releases reserved tickets for an EE_Registration
+	 * by default, will NOT release tickets for APPROVED registrations
+	 *
+	 * @param EE_Registration $registration
+	 * @param EE_Transaction  $transaction
+	 * @return int
+	 * @throws EE_Error
+	 */
+	protected function _release_reserved_ticket_for_registration(
+		EE_Registration $registration,
+		EE_Transaction $transaction
+	) {
+		$STS_ID = $transaction->status_ID();
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+			echo self::$nl . ' . . registration->ID: ' . $registration->ID();
+			echo self::$nl . ' . . registration->status_ID: ' . $registration->status_ID();
+			echo self::$nl . ' . . transaction->status_ID(): ' . $STS_ID;
+		}
+		if (// release Tickets for Failed Transactions and Abandoned Transactions
+			$STS_ID === EEM_Transaction::failed_status_code
+			|| $STS_ID === EEM_Transaction::abandoned_status_code
+			|| (
+				// also release Tickets for Incomplete Transactions, but ONLY if the Registrations are NOT Approved
+				$STS_ID === EEM_Transaction::incomplete_status_code
+				&& $registration->status_ID() !== EEM_Registration::status_id_approved
+			)
+		) {
+			if (self::debug) {
+				echo self::$nl . self::$nl . ' . . RELEASE RESERVED TICKET';
+				$rsrvd = $registration->get_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true);
+				echo self::$nl . ' . . . registration HAS_RESERVED_TICKET_KEY: ';
+				var_dump($rsrvd);
+			}
+			$registration->release_reserved_ticket(true, 'TicketSalesMonitor:' . __LINE__);
+			return 1;
+		}
+		return 0;
+	}
+
+
+
+	/********************************** SESSION_CART_RESET  **********************************/
+
+
+	/**
+	 * callback hooked into 'AHEE__EE_Session__reset_cart__before_reset'
+	 *
+	 * @param EE_Session $session
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public static function session_cart_reset(EE_Session $session)
+	{
+		// don't release tickets if checkout was already reset
+		if (did_action('AHEE__EE_Session__reset_checkout__before_reset')) {
+			return;
+		}
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+		}
+		// first check of the session has a valid Checkout object
+		$checkout = $session->checkout();
+		if ($checkout instanceof EE_Checkout) {
+			// and use that to clear ticket reservations because it will update the associated registration meta data
+			EED_Ticket_Sales_Monitor::instance()->_session_checkout_reset($checkout);
+			return;
+		}
+		$cart = $session->cart();
+		if ($cart instanceof EE_Cart) {
+			if (self::debug) {
+				echo self::$nl . self::$nl . ' cart instance of EE_Cart: ';
+			}
+			EED_Ticket_Sales_Monitor::instance()->_session_cart_reset($cart, $session);
+		} else {
+			if (self::debug) {
+				echo self::$nl . self::$nl . ' invalid EE_Cart: ';
+				var_export($cart, true);
+			}
+		}
+	}
+
+
+	/**
+	 * releases reserved tickets in the EE_Cart
+	 *
+	 * @param EE_Cart $cart
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _session_cart_reset(EE_Cart $cart, EE_Session $session)
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+		}
+		$ticket_line_items = $cart->get_tickets();
+		if (empty($ticket_line_items)) {
+			return;
+		}
+		if (self::debug) {
+			echo '<br /> . ticket_line_item count: ' . count($ticket_line_items);
+		}
+		foreach ($ticket_line_items as $ticket_line_item) {
+			if (self::debug) {
+				echo self::$nl . ' . ticket_line_item->ID(): ' . $ticket_line_item->ID();
+			}
+			if ($ticket_line_item instanceof EE_Line_Item && $ticket_line_item->OBJ_type() === 'Ticket') {
+				if (self::debug) {
+					echo self::$nl . ' . . ticket_line_item->OBJ_ID(): ' . $ticket_line_item->OBJ_ID();
+				}
+				$ticket = EEM_Ticket::instance()->get_one_by_ID($ticket_line_item->OBJ_ID());
+				if ($ticket instanceof EE_Ticket) {
+					if (self::debug) {
+						echo self::$nl . ' . . ticket->ID(): ' . $ticket->ID();
+						echo self::$nl . ' . . ticket_line_item->quantity(): ' . $ticket_line_item->quantity();
+					}
+					$ticket->add_extra_meta(
+						EE_Ticket::META_KEY_TICKET_RESERVATIONS,
+						__LINE__ . ') ' . __METHOD__ . '() SID = ' . $session->id()
+					);
+					$this->_release_reserved_ticket($ticket, $ticket_line_item->quantity());
+				}
+			}
+		}
+		if (self::debug) {
+			echo self::$nl . self::$nl . ' RESET COMPLETED ';
+		}
+	}
+
+
+
+	/********************************** SESSION_CHECKOUT_RESET  **********************************/
+
+
+	/**
+	 * callback hooked into 'AHEE__EE_Session__reset_checkout__before_reset'
+	 *
+	 * @param EE_Session $session
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidSessionDataException
+	 */
+	public static function session_checkout_reset(EE_Session $session)
+	{
+		// don't release tickets if cart was already reset
+		if (did_action('AHEE__EE_Session__reset_cart__before_reset')) {
+			return;
+		}
+		$checkout = $session->checkout();
+		if ($checkout instanceof EE_Checkout) {
+			EED_Ticket_Sales_Monitor::instance()->_session_checkout_reset($checkout);
+		}
+	}
+
+
+	/**
+	 * releases reserved tickets for the EE_Checkout->transaction
+	 *
+	 * @param EE_Checkout $checkout
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidSessionDataException
+	 */
+	protected function _session_checkout_reset(EE_Checkout $checkout)
+	{
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+		}
+		// we want to release the each registration's reserved tickets if the session was cleared, but not if this is a revisit
+		if ($checkout->revisit || ! $checkout->transaction instanceof EE_Transaction) {
+			return;
+		}
+		$this->_release_all_reserved_tickets_for_transaction($checkout->transaction);
+	}
+
+
+
+	/********************************** SESSION_EXPIRED_RESET  **********************************/
+
+
+	/**
+	 * @param    EE_Session $session
+	 * @return    void
+	 */
+	public static function session_expired_reset(EE_Session $session)
+	{
+	}
+
+
+
+	/********************************** PROCESS_ABANDONED_TRANSACTIONS  **********************************/
+
+
+	/**
+	 * releases reserved tickets for all registrations of an ABANDONED EE_Transaction
+	 * by default, will NOT release tickets for free transactions, or any that have received a payment
+	 *
+	 * @param EE_Transaction $transaction
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidSessionDataException
+	 */
+	public static function process_abandoned_transactions(EE_Transaction $transaction)
+	{
+		// is this TXN free or has any money been paid towards this TXN? If so, then leave it alone
+		if ($transaction->is_free() || $transaction->paid() > 0) {
+			if (self::debug) {
+				// DEBUG LOG
+				EEH_Debug_Tools::log(
+					__CLASS__,
+					__FUNCTION__,
+					__LINE__,
+					array($transaction),
+					false,
+					'EE_Transaction: ' . $transaction->ID()
+				);
+			}
+			return;
+		}
+		// have their been any successful payments made ?
+		$payments = $transaction->payments();
+		foreach ($payments as $payment) {
+			if ($payment instanceof EE_Payment && $payment->status() === EEM_Payment::status_id_approved) {
+				if (self::debug) {
+					// DEBUG LOG
+					EEH_Debug_Tools::log(
+						__CLASS__,
+						__FUNCTION__,
+						__LINE__,
+						array($payment),
+						false,
+						'EE_Transaction: ' . $transaction->ID()
+					);
+				}
+				return;
+			}
+		}
+		// since you haven't even attempted to pay for your ticket...
+		EED_Ticket_Sales_Monitor::instance()->_release_all_reserved_tickets_for_transaction($transaction);
+	}
+
+
+
+	/********************************** PROCESS_FAILED_TRANSACTIONS  **********************************/
+
+
+	/**
+	 * releases reserved tickets for absolutely ALL registrations of a FAILED EE_Transaction
+	 *
+	 * @param EE_Transaction $transaction
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidSessionDataException
+	 */
+	public static function process_failed_transactions(EE_Transaction $transaction)
+	{
+		// since you haven't even attempted to pay for your ticket...
+		EED_Ticket_Sales_Monitor::instance()->_release_all_reserved_tickets_for_transaction($transaction);
+	}
+
+
+
+	/********************************** RESET RESERVATION COUNTS  *********************************/
+
+
+	/**
+	 * Resets all ticket and datetime reserved counts to zero
+	 * Tickets that are currently associated with a Transaction that is in progress
+	 *
+	 * @throws EE_Error
+	 * @throws DomainException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidArgumentException
+	 * @throws UnexpectedEntityException
+	 */
+	public static function reset_reservation_counts()
+	{
+		/** @var EE_Line_Item[] $valid_reserved_tickets */
+		$valid_reserved_tickets = array();
+		/** @var EE_Transaction[] $transactions_not_in_progress */
+		$transactions_not_in_progress = EEM_Transaction::instance()->get_transactions_not_in_progress();
+		foreach ($transactions_not_in_progress as $transaction) {
+			// if this TXN has been fully completed, then skip it
+			if ($transaction->reg_step_completed('finalize_registration')) {
+				continue;
+			}
+			$total_line_item = $transaction->total_line_item();
+			// $transaction_in_progress->line
+			if (! $total_line_item instanceof EE_Line_Item) {
+				throw new DomainException(
+					esc_html__(
+						'Transaction does not have a valid Total Line Item associated with it.',
+						'event_espresso'
+					)
+				);
+			}
+			$valid_reserved_tickets += EED_Ticket_Sales_Monitor::get_ticket_line_items_for_grand_total(
+				$total_line_item
+			);
+		}
+		$total_line_items = EEM_Line_Item::instance()->get_total_line_items_for_active_carts();
+		foreach ($total_line_items as $total_line_item) {
+			$valid_reserved_tickets += EED_Ticket_Sales_Monitor::get_ticket_line_items_for_grand_total(
+				$total_line_item
+			);
+		}
+		$tickets_with_reservations = EEM_Ticket::instance()->get_tickets_with_reservations();
+		return EED_Ticket_Sales_Monitor::release_reservations_for_tickets(
+			$tickets_with_reservations,
+			$valid_reserved_tickets,
+			__FUNCTION__
+		);
+	}
+
+
+	/**
+	 * @param EE_Line_Item $total_line_item
+	 * @return EE_Line_Item[]
+	 */
+	private static function get_ticket_line_items_for_grand_total(EE_Line_Item $total_line_item)
+	{
+		/** @var EE_Line_Item[] $valid_reserved_tickets */
+		$valid_reserved_tickets = array();
+		$ticket_line_items = EEH_Line_Item::get_ticket_line_items($total_line_item);
+		foreach ($ticket_line_items as $ticket_line_item) {
+			if ($ticket_line_item instanceof EE_Line_Item) {
+				$valid_reserved_tickets[] = $ticket_line_item;
+			}
+		}
+		return $valid_reserved_tickets;
+	}
+
+
+	/**
+	 * @param EE_Ticket[]    $tickets_with_reservations
+	 * @param EE_Line_Item[] $valid_reserved_ticket_line_items
+	 * @return int
+	 * @throws UnexpectedEntityException
+	 * @throws DomainException
+	 * @throws EE_Error
+	 */
+	private static function release_reservations_for_tickets(
+		array $tickets_with_reservations,
+		array $valid_reserved_ticket_line_items = array(),
+		$source
+	) {
+		if (self::debug) {
+			echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
+		}
+		$total_tickets_released = 0;
+		$sold_out_events = array();
+		foreach ($tickets_with_reservations as $ticket_with_reservations) {
+			if (! $ticket_with_reservations instanceof EE_Ticket) {
+				continue;
+			}
+			$reserved_qty = $ticket_with_reservations->reserved();
+			if (self::debug) {
+				echo self::$nl . ' . $ticket_with_reservations->ID(): ' . $ticket_with_reservations->ID();
+				echo self::$nl . ' . $reserved_qty: ' . $reserved_qty;
+			}
+			foreach ($valid_reserved_ticket_line_items as $valid_reserved_ticket_line_item) {
+				if ($valid_reserved_ticket_line_item instanceof EE_Line_Item
+					&& $valid_reserved_ticket_line_item->OBJ_ID() === $ticket_with_reservations->ID()
+				) {
+					if (self::debug) {
+						echo self::$nl . ' . $valid_reserved_ticket_line_item->quantity(): '
+							 . $valid_reserved_ticket_line_item->quantity();
+					}
+					$reserved_qty -= $valid_reserved_ticket_line_item->quantity();
+				}
+			}
+			if ($reserved_qty > 0) {
+				$ticket_with_reservations->add_extra_meta(
+					EE_Ticket::META_KEY_TICKET_RESERVATIONS,
+					__LINE__ . ') ' . $source . '()'
+				);
+				$ticket_with_reservations->decreaseReserved($reserved_qty, true, 'TicketSalesMonitor:' . __LINE__);
+				$ticket_with_reservations->save();
+				$total_tickets_released += $reserved_qty;
+				$event = $ticket_with_reservations->get_related_event();
+				// track sold out events
+				if ($event instanceof EE_Event && $event->is_sold_out()) {
+					$sold_out_events[] = $event;
+				}
+			}
+		}
+		if (self::debug) {
+			echo self::$nl . ' . $total_tickets_released: ' . $total_tickets_released;
+		}
+		// double check whether sold out events should remain sold out after releasing tickets
+		if ($sold_out_events !== array()) {
+			foreach ($sold_out_events as $sold_out_event) {
+				/** @var EE_Event $sold_out_event */
+				$sold_out_event->perform_sold_out_status_check();
+			}
+		}
+		return $total_tickets_released;
+	}
+
+
+
+	/********************************** SHUTDOWN  **********************************/
+
+
+	/**
+	 * @param int $timestamp
+	 * @return false|int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public static function clear_expired_line_items_with_no_transaction($timestamp = 0)
+	{
+		/** @type WPDB $wpdb */
+		global $wpdb;
+		if (! absint($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 $wpdb->query(
+			$wpdb->prepare(
+				'DELETE FROM ' . EEM_Line_Item::instance()->table() . '
                 WHERE TXN_ID = 0 AND LIN_timestamp <= %s',
-                // use GMT time because that's what LIN_timestamps are in
-                date('Y-m-d H:i:s', $timestamp)
-            )
-        );
-    }
+				// use GMT time because that's what LIN_timestamps are in
+				date('Y-m-d H:i:s', $timestamp)
+			)
+		);
+	}
 }

Spacing +83 added lines, -83 removed lines

@@ -182,7 +182,7 @@ 
     public static function release_tickets_for_expired_carts()
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'()';
         }
         do_action('AHEE__EED_Ticket_Sales_Monitor__release_tickets_for_expired_carts__begin');
         $expired_ticket_IDs = array();
@@ -193,29 +193,29 @@ 
         $timestamp = $session_lifespan->expiration();
         $expired_ticket_line_items = EEM_Line_Item::instance()->getTicketLineItemsForExpiredCarts($timestamp);
         if (self::debug) {
-            echo self::$nl . ' . time(): ' . time();
-            echo self::$nl . ' . time() as date: ' . date('Y-m-d H:i a');
-            echo self::$nl . ' . session expiration: ' . $session_lifespan->expiration();
-            echo self::$nl . ' . session expiration as date: ' . date('Y-m-d H:i a', $session_lifespan->expiration());
-            echo self::$nl . ' . timestamp: ' . $timestamp;
-            echo self::$nl . ' . $expired_ticket_line_items: ' . count($expired_ticket_line_items);
+            echo self::$nl.' . time(): '.time();
+            echo self::$nl.' . time() as date: '.date('Y-m-d H:i a');
+            echo self::$nl.' . session expiration: '.$session_lifespan->expiration();
+            echo self::$nl.' . session expiration as date: '.date('Y-m-d H:i a', $session_lifespan->expiration());
+            echo self::$nl.' . timestamp: '.$timestamp;
+            echo self::$nl.' . $expired_ticket_line_items: '.count($expired_ticket_line_items);
         }
-        if (! empty($expired_ticket_line_items)) {
+        if ( ! empty($expired_ticket_line_items)) {
             foreach ($expired_ticket_line_items as $expired_ticket_line_item) {
-                if (! $expired_ticket_line_item instanceof EE_Line_Item) {
+                if ( ! $expired_ticket_line_item instanceof EE_Line_Item) {
                     continue;
                 }
-                $expired_ticket_IDs[ $expired_ticket_line_item->OBJ_ID() ] = $expired_ticket_line_item->OBJ_ID();
+                $expired_ticket_IDs[$expired_ticket_line_item->OBJ_ID()] = $expired_ticket_line_item->OBJ_ID();
                 if (self::debug) {
-                    echo self::$nl . ' . $expired_ticket_line_item->OBJ_ID(): ' . $expired_ticket_line_item->OBJ_ID();
-                    echo self::$nl . ' . $expired_ticket_line_item->timestamp(): '
+                    echo self::$nl.' . $expired_ticket_line_item->OBJ_ID(): '.$expired_ticket_line_item->OBJ_ID();
+                    echo self::$nl.' . $expired_ticket_line_item->timestamp(): '
                          . date(
                              'Y-m-d h:i a',
                              $expired_ticket_line_item->timestamp(true)
                          );
                 }
             }
-            if (! empty($expired_ticket_IDs)) {
+            if ( ! empty($expired_ticket_IDs)) {
                 EED_Ticket_Sales_Monitor::release_reservations_for_tickets(
                     \EEM_Ticket::instance()->get_tickets_with_IDs($expired_ticket_IDs),
                     array(),
@@ -253,8 +253,8 @@ 
             $qty = EED_Ticket_Sales_Monitor::instance()->_validate_ticket_sale($ticket, $qty);
         }
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
-            echo self::$nl . self::$nl . '<b> RETURNED QTY: ' . $qty . '</b>';
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'()';
+            echo self::$nl.self::$nl.'<b> RETURNED QTY: '.$qty.'</b>';
         }
         return $qty;
     }
@@ -272,36 +272,36 @@ 
     protected function _validate_ticket_sale(EE_Ticket $ticket, $qty = 1)
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
         }
-        if (! $ticket instanceof EE_Ticket) {
+        if ( ! $ticket instanceof EE_Ticket) {
             return 0;
         }
         if (self::debug) {
-            echo self::$nl . '<b> . ticket->ID: ' . $ticket->ID() . '</b>';
-            echo self::$nl . ' . original ticket->reserved: ' . $ticket->reserved();
+            echo self::$nl.'<b> . ticket->ID: '.$ticket->ID().'</b>';
+            echo self::$nl.' . original ticket->reserved: '.$ticket->reserved();
         }
         $ticket->refresh_from_db();
         // first let's determine the ticket availability based on sales
         $available = $ticket->qty('saleable');
         if (self::debug) {
-            echo self::$nl . ' . . . ticket->qty: ' . $ticket->qty();
-            echo self::$nl . ' . . . ticket->sold: ' . $ticket->sold();
-            echo self::$nl . ' . . . ticket->reserved: ' . $ticket->reserved();
-            echo self::$nl . ' . . . ticket->qty(saleable): ' . $ticket->qty('saleable');
-            echo self::$nl . ' . . . available: ' . $available;
+            echo self::$nl.' . . . ticket->qty: '.$ticket->qty();
+            echo self::$nl.' . . . ticket->sold: '.$ticket->sold();
+            echo self::$nl.' . . . ticket->reserved: '.$ticket->reserved();
+            echo self::$nl.' . . . ticket->qty(saleable): '.$ticket->qty('saleable');
+            echo self::$nl.' . . . available: '.$available;
         }
         if ($available < 1) {
             $this->_ticket_sold_out($ticket);
             return 0;
         }
         if (self::debug) {
-            echo self::$nl . ' . . . qty: ' . $qty;
+            echo self::$nl.' . . . qty: '.$qty;
         }
         if ($available < $qty) {
             $qty = $available;
             if (self::debug) {
-                echo self::$nl . ' . . . QTY ADJUSTED: ' . $qty;
+                echo self::$nl.' . . . QTY ADJUSTED: '.$qty;
             }
             $this->_ticket_quantity_decremented($ticket);
         }
@@ -324,9 +324,9 @@ 
     protected function _reserve_ticket(EE_Ticket $ticket, $quantity = 1)
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . ' . . . INCREASE RESERVED: ' . $quantity;
+            echo self::$nl.self::$nl.' . . . INCREASE RESERVED: '.$quantity;
         }
-        return $ticket->increaseReserved($quantity, 'TicketSalesMonitor:' . __LINE__);
+        return $ticket->increaseReserved($quantity, 'TicketSalesMonitor:'.__LINE__);
     }
 
 
@@ -339,12 +339,12 @@ 
     protected function _release_reserved_ticket(EE_Ticket $ticket, $quantity = 1)
     {
         if (self::debug) {
-            echo self::$nl . ' . . . ticket->ID: ' . $ticket->ID();
-            echo self::$nl . ' . . . ticket->reserved before: ' . $ticket->reserved();
+            echo self::$nl.' . . . ticket->ID: '.$ticket->ID();
+            echo self::$nl.' . . . ticket->reserved before: '.$ticket->reserved();
         }
-        $ticket->decreaseReserved($quantity, true, 'TicketSalesMonitor:' . __LINE__);
+        $ticket->decreaseReserved($quantity, true, 'TicketSalesMonitor:'.__LINE__);
         if (self::debug) {
-            echo self::$nl . ' . . . ticket->reserved after: ' . $ticket->reserved();
+            echo self::$nl.' . . . ticket->reserved after: '.$ticket->reserved();
         }
         return $ticket->save() ? 1 : 0;
     }
@@ -361,8 +361,8 @@ 
     protected function _ticket_sold_out(EE_Ticket $ticket)
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-            echo self::$nl . ' . . ticket->name: ' . $this->_get_ticket_and_event_name($ticket);
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
+            echo self::$nl.' . . ticket->name: '.$this->_get_ticket_and_event_name($ticket);
         }
         $this->sold_out_tickets[] = $this->_get_ticket_and_event_name($ticket);
     }
@@ -379,8 +379,8 @@ 
     protected function _ticket_quantity_decremented(EE_Ticket $ticket)
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-            echo self::$nl . ' . . ticket->name: ' . $this->_get_ticket_and_event_name($ticket);
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
+            echo self::$nl.' . . ticket->name: '.$this->_get_ticket_and_event_name($ticket);
         }
         $this->decremented_tickets[] = $this->_get_ticket_and_event_name($ticket);
     }
@@ -431,7 +431,7 @@ 
         if ($ticket instanceof EE_Ticket) {
             $ticket->add_extra_meta(
                 EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-                __LINE__ . ') ' . __METHOD__ . '()'
+                __LINE__.') '.__METHOD__.'()'
             );
             if ($quantity > 0) {
                 EED_Ticket_Sales_Monitor::instance()->_reserve_ticket($ticket, $quantity);
@@ -454,7 +454,7 @@ 
     {
         $ticket->add_extra_meta(
             EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-            __LINE__ . ') ' . __METHOD__ . '()'
+            __LINE__.') '.__METHOD__.'()'
         );
         EED_Ticket_Sales_Monitor::instance()->_release_reserved_ticket($ticket, $quantity);
     }
@@ -489,7 +489,7 @@ 
     protected function _post_notices()
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
         }
         $refresh_msg = '';
         $none_added_msg = '';
@@ -500,7 +500,7 @@ 
             );
             $none_added_msg = __('No tickets were added for the event.', 'event_espresso');
         }
-        if (! empty($this->sold_out_tickets)) {
+        if ( ! empty($this->sold_out_tickets)) {
             EE_Error::add_attention(
                 sprintf(
                     apply_filters(
@@ -523,7 +523,7 @@ 
             // and reset the cart
             EED_Ticket_Sales_Monitor::session_cart_reset(EE_Registry::instance()->SSN);
         }
-        if (! empty($this->decremented_tickets)) {
+        if ( ! empty($this->decremented_tickets)) {
             EE_Error::add_attention(
                 sprintf(
                     apply_filters(
@@ -560,9 +560,9 @@ 
     protected function _release_all_reserved_tickets_for_transaction(EE_Transaction $transaction)
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-            echo self::$nl . ' . transaction->ID: ' . $transaction->ID();
-            echo self::$nl . ' . TXN status_ID: ' . $transaction->status_ID();
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
+            echo self::$nl.' . transaction->ID: '.$transaction->ID();
+            echo self::$nl.' . TXN status_ID: '.$transaction->status_ID();
         }
         // check if 'finalize_registration' step has been completed...
         $finalized = $transaction->reg_step_completed('finalize_registration');
@@ -574,13 +574,13 @@ 
                 __LINE__,
                 array('finalized' => $finalized),
                 false,
-                'EE_Transaction: ' . $transaction->ID()
+                'EE_Transaction: '.$transaction->ID()
             );
         }
         // how many tickets were released
         $count = 0;
         if (self::debug) {
-            echo self::$nl . ' . . . TXN finalized: ' . $finalized;
+            echo self::$nl.' . . . TXN finalized: '.$finalized;
         }
         $release_tickets_with_TXN_status = array(
             EEM_Transaction::failed_status_code,
@@ -589,27 +589,27 @@ 
         );
         $events = array();
         // if the session is getting cleared BEFORE the TXN has been finalized or the transaction is not completed
-        if (! $finalized || in_array($transaction->status_ID(), $release_tickets_with_TXN_status, true)) {
+        if ( ! $finalized || in_array($transaction->status_ID(), $release_tickets_with_TXN_status, true)) {
             // cancel any reserved tickets for registrations that were not approved
             $registrations = $transaction->registrations();
             if (self::debug) {
-                echo self::$nl . ' . . . # registrations: ' . count($registrations);
+                echo self::$nl.' . . . # registrations: '.count($registrations);
                 $reg = reset($registrations);
                 $ticket = $reg->ticket();
                 if ($ticket instanceof EE_Ticket) {
                     $ticket->add_extra_meta(
                         EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-                        __LINE__ . ') Release All Tickets TXN:' . $transaction->ID()
+                        __LINE__.') Release All Tickets TXN:'.$transaction->ID()
                     );
                 }
             }
-            if (! empty($registrations)) {
+            if ( ! empty($registrations)) {
                 foreach ($registrations as $registration) {
                     if ($registration instanceof EE_Registration
                         && $this->_release_reserved_ticket_for_registration($registration, $transaction)
                     ) {
                         $count++;
-                        $events[ $registration->event_ID() ] = $registration->event();
+                        $events[$registration->event_ID()] = $registration->event();
                     }
                 }
             }
@@ -639,10 +639,10 @@ 
     ) {
         $STS_ID = $transaction->status_ID();
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
-            echo self::$nl . ' . . registration->ID: ' . $registration->ID();
-            echo self::$nl . ' . . registration->status_ID: ' . $registration->status_ID();
-            echo self::$nl . ' . . transaction->status_ID(): ' . $STS_ID;
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
+            echo self::$nl.' . . registration->ID: '.$registration->ID();
+            echo self::$nl.' . . registration->status_ID: '.$registration->status_ID();
+            echo self::$nl.' . . transaction->status_ID(): '.$STS_ID;
         }
         if (// release Tickets for Failed Transactions and Abandoned Transactions
             $STS_ID === EEM_Transaction::failed_status_code
@@ -654,12 +654,12 @@ 
             )
         ) {
             if (self::debug) {
-                echo self::$nl . self::$nl . ' . . RELEASE RESERVED TICKET';
+                echo self::$nl.self::$nl.' . . RELEASE RESERVED TICKET';
                 $rsrvd = $registration->get_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true);
-                echo self::$nl . ' . . . registration HAS_RESERVED_TICKET_KEY: ';
+                echo self::$nl.' . . . registration HAS_RESERVED_TICKET_KEY: ';
                 var_dump($rsrvd);
             }
-            $registration->release_reserved_ticket(true, 'TicketSalesMonitor:' . __LINE__);
+            $registration->release_reserved_ticket(true, 'TicketSalesMonitor:'.__LINE__);
             return 1;
         }
         return 0;
@@ -688,7 +688,7 @@ 
             return;
         }
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
         }
         // first check of the session has a valid Checkout object
         $checkout = $session->checkout();
@@ -700,12 +700,12 @@ 
         $cart = $session->cart();
         if ($cart instanceof EE_Cart) {
             if (self::debug) {
-                echo self::$nl . self::$nl . ' cart instance of EE_Cart: ';
+                echo self::$nl.self::$nl.' cart instance of EE_Cart: ';
             }
             EED_Ticket_Sales_Monitor::instance()->_session_cart_reset($cart, $session);
         } else {
             if (self::debug) {
-                echo self::$nl . self::$nl . ' invalid EE_Cart: ';
+                echo self::$nl.self::$nl.' invalid EE_Cart: ';
                 var_export($cart, true);
             }
         }
@@ -726,39 +726,39 @@ 
     protected function _session_cart_reset(EE_Cart $cart, EE_Session $session)
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
         }
         $ticket_line_items = $cart->get_tickets();
         if (empty($ticket_line_items)) {
             return;
         }
         if (self::debug) {
-            echo '<br /> . ticket_line_item count: ' . count($ticket_line_items);
+            echo '<br /> . ticket_line_item count: '.count($ticket_line_items);
         }
         foreach ($ticket_line_items as $ticket_line_item) {
             if (self::debug) {
-                echo self::$nl . ' . ticket_line_item->ID(): ' . $ticket_line_item->ID();
+                echo self::$nl.' . ticket_line_item->ID(): '.$ticket_line_item->ID();
             }
             if ($ticket_line_item instanceof EE_Line_Item && $ticket_line_item->OBJ_type() === 'Ticket') {
                 if (self::debug) {
-                    echo self::$nl . ' . . ticket_line_item->OBJ_ID(): ' . $ticket_line_item->OBJ_ID();
+                    echo self::$nl.' . . ticket_line_item->OBJ_ID(): '.$ticket_line_item->OBJ_ID();
                 }
                 $ticket = EEM_Ticket::instance()->get_one_by_ID($ticket_line_item->OBJ_ID());
                 if ($ticket instanceof EE_Ticket) {
                     if (self::debug) {
-                        echo self::$nl . ' . . ticket->ID(): ' . $ticket->ID();
-                        echo self::$nl . ' . . ticket_line_item->quantity(): ' . $ticket_line_item->quantity();
+                        echo self::$nl.' . . ticket->ID(): '.$ticket->ID();
+                        echo self::$nl.' . . ticket_line_item->quantity(): '.$ticket_line_item->quantity();
                     }
                     $ticket->add_extra_meta(
                         EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-                        __LINE__ . ') ' . __METHOD__ . '() SID = ' . $session->id()
+                        __LINE__.') '.__METHOD__.'() SID = '.$session->id()
                     );
                     $this->_release_reserved_ticket($ticket, $ticket_line_item->quantity());
                 }
             }
         }
         if (self::debug) {
-            echo self::$nl . self::$nl . ' RESET COMPLETED ';
+            echo self::$nl.self::$nl.' RESET COMPLETED ';
         }
     }
 
@@ -799,7 +799,7 @@ 
     protected function _session_checkout_reset(EE_Checkout $checkout)
     {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '() ';
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'() ';
         }
         // we want to release the each registration's reserved tickets if the session was cleared, but not if this is a revisit
         if ($checkout->revisit || ! $checkout->transaction instanceof EE_Transaction) {
@@ -847,7 +847,7 @@ 
                     __LINE__,
                     array($transaction),
                     false,
-                    'EE_Transaction: ' . $transaction->ID()
+                    'EE_Transaction: '.$transaction->ID()
                 );
             }
             return;
@@ -864,7 +864,7 @@ 
                         __LINE__,
                         array($payment),
                         false,
-                        'EE_Transaction: ' . $transaction->ID()
+                        'EE_Transaction: '.$transaction->ID()
                     );
                 }
                 return;
@@ -922,7 +922,7 @@ 
             }
             $total_line_item = $transaction->total_line_item();
             // $transaction_in_progress->line
-            if (! $total_line_item instanceof EE_Line_Item) {
+            if ( ! $total_line_item instanceof EE_Line_Item) {
                 throw new DomainException(
                     esc_html__(
                         'Transaction does not have a valid Total Line Item associated with it.',
@@ -981,25 +981,25 @@ 
         $source
     ) {
         if (self::debug) {
-            echo self::$nl . self::$nl . __LINE__ . ') ' . __METHOD__ . '()';
+            echo self::$nl.self::$nl.__LINE__.') '.__METHOD__.'()';
         }
         $total_tickets_released = 0;
         $sold_out_events = array();
         foreach ($tickets_with_reservations as $ticket_with_reservations) {
-            if (! $ticket_with_reservations instanceof EE_Ticket) {
+            if ( ! $ticket_with_reservations instanceof EE_Ticket) {
                 continue;
             }
             $reserved_qty = $ticket_with_reservations->reserved();
             if (self::debug) {
-                echo self::$nl . ' . $ticket_with_reservations->ID(): ' . $ticket_with_reservations->ID();
-                echo self::$nl . ' . $reserved_qty: ' . $reserved_qty;
+                echo self::$nl.' . $ticket_with_reservations->ID(): '.$ticket_with_reservations->ID();
+                echo self::$nl.' . $reserved_qty: '.$reserved_qty;
             }
             foreach ($valid_reserved_ticket_line_items as $valid_reserved_ticket_line_item) {
                 if ($valid_reserved_ticket_line_item instanceof EE_Line_Item
                     && $valid_reserved_ticket_line_item->OBJ_ID() === $ticket_with_reservations->ID()
                 ) {
                     if (self::debug) {
-                        echo self::$nl . ' . $valid_reserved_ticket_line_item->quantity(): '
+                        echo self::$nl.' . $valid_reserved_ticket_line_item->quantity(): '
                              . $valid_reserved_ticket_line_item->quantity();
                     }
                     $reserved_qty -= $valid_reserved_ticket_line_item->quantity();
@@ -1008,9 +1008,9 @@ 
             if ($reserved_qty > 0) {
                 $ticket_with_reservations->add_extra_meta(
                     EE_Ticket::META_KEY_TICKET_RESERVATIONS,
-                    __LINE__ . ') ' . $source . '()'
+                    __LINE__.') '.$source.'()'
                 );
-                $ticket_with_reservations->decreaseReserved($reserved_qty, true, 'TicketSalesMonitor:' . __LINE__);
+                $ticket_with_reservations->decreaseReserved($reserved_qty, true, 'TicketSalesMonitor:'.__LINE__);
                 $ticket_with_reservations->save();
                 $total_tickets_released += $reserved_qty;
                 $event = $ticket_with_reservations->get_related_event();
@@ -1021,7 +1021,7 @@ 
             }
         }
         if (self::debug) {
-            echo self::$nl . ' . $total_tickets_released: ' . $total_tickets_released;
+            echo self::$nl.' . $total_tickets_released: '.$total_tickets_released;
         }
         // double check whether sold out events should remain sold out after releasing tickets
         if ($sold_out_events !== array()) {
@@ -1050,7 +1050,7 @@ 
     {
         /** @type WPDB $wpdb */
         global $wpdb;
-        if (! absint($timestamp)) {
+        if ( ! absint($timestamp)) {
             /** @var EventEspresso\core\domain\values\session\SessionLifespan $session_lifespan */
             $session_lifespan = LoaderFactory::getLoader()->getShared(
                 'EventEspresso\core\domain\values\session\SessionLifespan'
@@ -1059,7 +1059,7 @@ 
         }
         return $wpdb->query(
             $wpdb->prepare(
-                'DELETE FROM ' . EEM_Line_Item::instance()->table() . '
+                'DELETE FROM '.EEM_Line_Item::instance()->table().'
                 WHERE TXN_ID = 0 AND LIN_timestamp <= %s',
                 // use GMT time because that's what LIN_timestamps are in
                 date('Y-m-d H:i:s', $timestamp)