1: <?php
  2: /**
  3:  * Helpers collection is used as a registry for loaded helpers and handles loading
  4:  * and constructing helper class objects.
  5:  *
  6:  * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
  7:  * Copyright 2005-2011, Cake Software Foundation, Inc. (http://cakefoundation.org)
  8:  *
  9:  * Licensed under The MIT License
 10:  * Redistributions of files must retain the above copyright notice.
 11:  *
 12:  * @copyright     Copyright 2005-2011, Cake Software Foundation, Inc. (http://cakefoundation.org)
 13:  * @link          http://cakephp.org CakePHP(tm) Project
 14:  * @package       Cake.View
 15:  * @since         CakePHP(tm) v 2.0
 16:  * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
 17:  */
 18: 
 19: App::uses('ObjectCollection', 'Utility');
 20: 
 21: /**
 22:  * Helpers collection is used as a registry for loaded helpers and handles loading
 23:  * and constructing helper class objects.
 24:  *
 25:  * @package       Cake.View
 26:  */
 27: class HelperCollection extends ObjectCollection {
 28: 
 29: /**
 30:  * View object to use when making helpers.
 31:  *
 32:  * @var View
 33:  */
 34:     protected $_View;
 35: 
 36: /**
 37:  * Constructor
 38:  *
 39:  * @param View $view
 40:  */
 41:     public function __construct(View $view) {
 42:         $this->_View = $view;
 43:     }
 44: 
 45: /**
 46:  * Loads/constructs a helper.  Will return the instance in the registry if it already exists.
 47:  * By setting `$enable` to false you can disable callbacks for a helper.  Alternatively you
 48:  * can set `$settings['enabled'] = false` to disable callbacks.  This alias is provided so that when
 49:  * declaring $helpers arrays you can disable callbacks on helpers.
 50:  *
 51:  * You can alias your helper as an existing helper by setting the 'className' key, i.e.,
 52:  * {{{
 53:  * public $helpers = array(
 54:  *   'Html' => array(
 55:  *     'className' => 'AliasedHtml'
 56:  *   );
 57:  * );
 58:  * }}}
 59:  * All calls to the `Html` helper would use `AliasedHtml` instead.
 60:  *
 61:  * @param string $helper Helper name to load
 62:  * @param array $settings Settings for the helper.
 63:  * @return Helper A helper object, Either the existing loaded helper or a new one.
 64:  * @throws MissingHelperException when the helper could not be found
 65:  */
 66:     public function load($helper, $settings = array()) {
 67:         if (is_array($settings) && isset($settings['className'])) {
 68:             $alias = $helper;
 69:             $helper = $settings['className'];
 70:         }
 71:         list($plugin, $name) = pluginSplit($helper, true);
 72:         if (!isset($alias)) {
 73:             $alias = $name;
 74:         }
 75: 
 76:         if (isset($this->_loaded[$alias])) {
 77:             return $this->_loaded[$alias];
 78:         }
 79:         $helperClass = $name . 'Helper';
 80:         App::uses($helperClass, $plugin . 'View/Helper');
 81:         if (!class_exists($helperClass)) {
 82:             throw new MissingHelperException(array(
 83:                 'class' => $helperClass,
 84:                 'plugin' => substr($plugin, 0, -1)
 85:             ));
 86:         }
 87:         $this->_loaded[$alias] = new $helperClass($this->_View, $settings);
 88: 
 89:         $vars = array('request', 'theme', 'plugin');
 90:         foreach ($vars as $var) {
 91:             $this->_loaded[$alias]->{$var} = $this->_View->{$var};
 92:         }
 93:         $enable = isset($settings['enabled']) ? $settings['enabled'] : true;
 94:         if ($enable === true) {
 95:             $this->_enabled[] = $alias;
 96:         }
 97:         return $this->_loaded[$alias];
 98:     }
 99: 
100: }