<?php
  /**
   * Copyright (c) 2013 Robin Appelman <icewind@owncloud.com>
   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */
  
  namespace OC\Hooks;
  
  /**
   * Class ForwardingEmitter
   *
   * allows forwarding all listen calls to other emitters
   *
   * @package OC\Hooks
   */
  abstract class ForwardingEmitter extends BasicEmitter {
  	/**
  	 * @var \OC\Hooks\Emitter[] array
  	 */
  	private $forwardEmitters = array();
  
  	/**
  	 * @param string $scope
  	 * @param string $method
  	 * @param callable $callback
  	 */
  	public function listen($scope, $method, $callback) {
  		parent::listen($scope, $method, $callback);
  		foreach ($this->forwardEmitters as $emitter) {
  			$emitter->listen($scope, $method, $callback);
  		}
  	}
  
  	/**
  	 * @param \OC\Hooks\Emitter $emitter
  	 */
  	protected function forward($emitter) {
  		$this->forwardEmitters[] = $emitter;
  
  		//forward all previously connected hooks
  		foreach ($this->listeners as $key => $listeners) {
  			list($scope, $method) = explode('::', $key, 2);
  			foreach ($listeners as $listener) {
  				$emitter->listen($scope, $method, $listener);
  			}
  		}
  	}
  }