BP_Messages_Message::send()

	public function send() {
		global $wpdb;

		$bp = buddypress();

		$this->sender_id = apply_filters( 'messages_message_sender_id_before_save', $this->sender_id, $this->id );
		$this->thread_id = apply_filters( 'messages_message_thread_id_before_save', $this->thread_id, $this->id );
		$this->subject   = apply_filters( 'messages_message_subject_before_save', $this->subject, $this->id );
		$this->message   = apply_filters( 'messages_message_content_before_save', $this->message, $this->id );
		$this->date_sent = apply_filters( 'messages_message_date_sent_before_save', $this->date_sent, $this->id );

		/**
		 * Fires before the current message item gets saved.
		 *
		 * Please use this hook to filter the properties above. Each part will be passed in.
		 *
		 * @since BuddyPress 1.0.0
		 *
		 * @param BP_Messages_Message $this Current instance of the message item being saved. Passed by reference.
		 */
		do_action_ref_array( 'messages_message_before_save', array( &$this ) );

		// Make sure we have at least one recipient before sending.
		if ( empty( $this->recipients ) ) {
			return false;
		}

		$new_thread = false;

		// If we have no thread_id then this is the first message of a new thread.
		if ( empty( $this->thread_id ) ) {
			$this->thread_id = (int) $wpdb->get_var( "SELECT MAX(thread_id) FROM {$bp->messages->table_name_messages}" ) + 1;
			$new_thread      = true;
		}

		// First insert the message into the messages table.
		if ( ! $wpdb->query( $wpdb->prepare( "INSERT INTO {$bp->messages->table_name_messages} ( thread_id, sender_id, subject, message, date_sent ) VALUES ( %d, %d, %s, %s, %s )", $this->thread_id, $this->sender_id, $this->subject, $this->message, $this->date_sent ) ) ) {
			return false;
		}

		static::$last_inserted_id = $this->id = $wpdb->insert_id;

		$recipient_ids = array();

		if ( $new_thread ) {
			// Add an recipient entry for all recipients.
			foreach ( (array) $this->recipients as $recipient ) {
				$wpdb->query( $wpdb->prepare( "INSERT INTO {$bp->messages->table_name_recipients} ( user_id, thread_id, unread_count ) VALUES ( %d, %d, 1 )", $recipient->user_id, $this->thread_id ) );
				$recipient_ids[] = $recipient->user_id;
			}

			// Add a sender recipient entry if the sender is not in the list of recipients.
			if ( ! in_array( $this->sender_id, $recipient_ids ) ) {
				$wpdb->query( $wpdb->prepare( "INSERT INTO {$bp->messages->table_name_recipients} ( user_id, thread_id ) VALUES ( %d, %d )", $this->sender_id, $this->thread_id ) );
			}
		} else {
			// Update the unread count for all recipients.
			$wpdb->query( $wpdb->prepare( "UPDATE {$bp->messages->table_name_recipients} SET unread_count = unread_count + 1, is_deleted = 0 WHERE thread_id = %d AND user_id != %d", $this->thread_id, $this->sender_id ) );
		}

		messages_remove_callback_values();

		/**
		 * Fires after the current message item has been saved.
		 *
		 * @since BuddyPress 1.0.0
		 *
		 * @param BP_Messages_Message $this Current instance of the message item being saved. Passed by reference.
		 */
		do_action_ref_array( 'messages_message_after_save', array( &$this ) );

		return $this->id;
	}