private function add_actions() {

		foreach ( $this->get_trigger_hooks() as $action ) {
			add_action( $action, array( $this, 'maybe_trigger_engagement' ), 777, 3 );
		}

		// Handlers are in charge of processing (awarding/sending) the email/cert/achievement.
		$handlers = array(
			'lifterlms_engagement_send_email'        => 'handle_email',
			'lifterlms_engagement_award_achievement' => 'handle_achievement',
			'lifterlms_engagement_award_certificate' => 'handle_certificate',
		);
		foreach ( $handlers as $action => $method ) {

			/**
			 * Adds an action for the deprecated method so that `remove_action()` calls
			 * on the old method will continue to remove the new method.
			 *
			 * When we *remove* the deprecated methods we can remove this logic.
			 */
			add_action( $action, array( $this, $method ) );

			// If the above action has been completely removed this will be false and we won't add the new method callback.
			$priority = has_action( $action, array( $this, $method ) );
			if ( false !== $priority ) {
				// Remove the deprecated action.
				remove_action( $action, array( $this, $method ) );
				// Call the new action at the specified priority. If the old action was restored at a different priority this will retain that customization.
				add_action( $action, array( 'LLMS_Engagement_Handler', $method ), $priority );
			}
		}

		add_action( 'deleted_post', array( $this, 'unschedule_delayed_engagements' ), 20, 2 );

	}