Cacher is the code snippet organizer for pro developers

<?php
/**
 * WARNING! THIS SNIPPET MAY BE OUTDATED.
 * The latest version of this snippet can be found in the Gravity Wiz Snippet Library:
 * https://github.com/gravitywiz/snippet-library/blob/master/gravity-forms/gw-notification-events.php
 */
/**
* Gravity Wiz // Gravity Forms // Notification Events
*
* Create custom notification events for Gravity Forms. Currently supports entry field update conditions.
*
* Future support will be added for time-based notification events, entry property updates, and more.
*
* @author    David Smith <david@gravitywiz.com>
* @license   GPL-2.0+
* @link      http://gravitywiz.com/...
* @copyright 2015 Gravity Wiz
*/
class GW_Notification_Event {

    public function __construct( $args ) {

        // make sure we're running the required minimum version of Gravity Forms
        if( ! property_exists( 'GFCommon', 'version' ) || ! version_compare( GFCommon::$version, '1.8', '>=' ) )
            return;

        $this->_args = wp_parse_args( $args, array(
            'form_id'     => false,
            'event_name'  => false,
            'event_slug'  => false,
            'object_type' => 'entry',
            'trigger'     => array()
        ) );

        extract( $this->_args );

        if( ! $event_name )
            return;

        add_filter( 'gform_notification_events', array( $this, 'add_notification_event' ) );
        add_filter( 'gform_notification', array( $this, 'add_notification_sent_entry_meta' ), 10, 3 );

        $this->add_trigger_listeners();

    }

    public function add_notification_event( $events ) {

        $form_id = rgget( 'id' );
        if( $this->is_applicable_form( $form_id ) ) {
	        $events[$this->get_event_slug()] = $this->_args['event_name'];
        }

        return $events;
    }

    public function get_event_slug() {

        if( $this->_args['event_slug'] )
            return $this->_args['event_slug'];

        $slug = strtolower( str_replace( ' ', '_', $this->_args['event_name'] ) );

        return $slug;
    }

    public function add_trigger_listeners() {

        if( is_callable( $this->_args['trigger'] ) ) {
            call_user_func( $this->_args['trigger'] );
            return;
        }

        $trigger_type = rgars( $this->_args['trigger'], 'type' );
        $func = array( $this, "process_trigger_{$trigger_type}" );

        switch( $trigger_type ) {
            case 'update_entry':
                add_action( 'gform_after_update_entry', $func, 10, 2 );
            break;
            case 'hook':

                list( $hook, $func, $priority, $parameter_count ) = array_pad( $this->_args['trigger']['args'], 4, false );

                // if no func is provided, use default naming convention: 'process_trigger_{hook}'
                if( ! $func ) {
                    $func = array( $this, "process_trigger_{$hook}" );
                }
                // assume that any string-based func is intended to be a function in this class
                else if( ! is_array( $func ) && is_callable( array( $this, $func ) ) ) {
                    $func = array( $this, $func );
                }

                if( ! is_callable( $func ) ) {
                    return;
                }

                add_action( $hook, $func, $priority ? $priority : 10, $parameter_count ? $parameter_count : 1 );

            break;
        }

    }

    public function process_trigger_update_entry( $form, $entry_id ) {

        $entry = GFAPI::get_entry( $entry_id );
        if( is_wp_error( $entry ) )
            return;

        $this->maybe_send_notifications( $form, $entry );

    }

    public function maybe_send_notifications( $form, $entry ) {

        $trigger_rules_met = GFCommon::evaluate_conditional_logic( $this->_args['trigger'], $form, $entry );
        if( ! $trigger_rules_met )
            return;

        $this->send_notifications( $this->get_event_slug(), $form, $entry );

    }

    public function send_notifications( $event, $form, $entry, $force_send = null ) {

        $notifications = GFCommon::get_notifications_to_send( $event, $form, $entry );
        $ids = array();

        foreach( $notifications as $notification ) {
            if( $force_send || ! gform_get_meta( $entry['id'], 'notification_' . $notification['id'] ) )
                $ids[] = $notification['id'];
        }

        GFCommon::send_notifications( $ids, $form, $entry, true, $event );

    }

    public function add_notification_sent_entry_meta( $notification, $form, $entry ) {

        if( rgar( $notification, 'event' ) == $this->get_event_slug() )
            gform_update_meta( $entry['id'], "notification_{$notification['id']}", 1 );

        return $notification;
    }

	function is_applicable_form( $form ) {

		$form_id = isset( $form['id'] ) ? $form['id'] : $form;

		return empty( $this->_args['form_id'] ) || $form_id == $this->_args['form_id'];
	}

}

# Usage Example

//new GW_Notification_Event( array(
//    'form_id'     => 1,
//    'event_name'  => $order_status['label'],
//    'object_type' => 'entry', // 'entry', 'field', 'form', 'user', etc
//    'trigger'    => array(
//        'type'      => 'update_entry',
//        'logicType' => 'all', // 'all' or 'any'
//        'rules'     => array(
//            array(
//                'fieldId'  => 5,
//                'operator' => 'is',
//                'value'    => $order_status['field_value']
//            )
//        )
//    )
//) );

# Advanced Usage Example

//class My_Custom_Notification_Event extends GW_Notification_Event {
//
//    public function process_trigger_gform_after_submission( $entry, $form ) {
//        $this->maybe_send_notifications( $form, $entry );
//    }
//
//}
//
//new My_Custom_Notification_Event( array(
//    'form_id'     => 387,
//    'event_name'  => 'After form is submitted',
//    'trigger'     => array(
//        'type' => 'hook',
//        'args' => array( 'gform_after_submission', false, 11, 2 )
//    )
//) );