/**
  * Updates the product sales if old and new order stati differ in stock size.
  *
  * @param int    $order_id
  * @param string $attendee_order_status
  * @param int    $ticket_id
  */
 public function update_sales_by_order_status($order_id, $attendee_order_status, $ticket_id)
 {
     $rsvp_options = $this->tickets_view->get_rsvp_options(null, false);
     $previous_order_status = get_post_meta($order_id, self::ATTENDEE_RSVP_KEY, true);
     if (!(isset($rsvp_options[$previous_order_status]) && isset($rsvp_options[$attendee_order_status]))) {
         return;
     }
     $previous_order_status_stock_size = $rsvp_options[$previous_order_status]['decrease_stock_by'];
     $attendee_order_status_stock_size = $rsvp_options[$attendee_order_status]['decrease_stock_by'];
     if ($previous_order_status_stock_size == $attendee_order_status_stock_size) {
         return;
     }
     $sales = (int) get_post_meta($ticket_id, 'total_sales', true);
     $diff = $attendee_order_status_stock_size - $previous_order_status_stock_size;
     update_post_meta($ticket_id, 'total_sales', $sales + $diff);
 }