Subversion Repositories SmartDukaan

<?php

/**

 * Helpers collection is used as a registry for loaded helpers and handles loading

 * and constructing helper class objects.

 *

 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)

 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 *

 * Licensed under The MIT License

 * For full copyright and license information, please see the LICENSE.txt

 * Redistributions of files must retain the above copyright notice.

 *

 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 * @link          http://cakephp.org CakePHP(tm) Project

 * @package       Cake.View

 * @since         CakePHP(tm) v 2.0

 * @license       http://www.opensource.org/licenses/mit-license.php MIT License

 */

App::uses('ObjectCollection', 'Utility');

App::uses('CakeEventListener', 'Event');

/**

 * Helpers collection is used as a registry for loaded helpers and handles loading

 * and constructing helper class objects.

 *

 * @package       Cake.View

 */

class HelperCollection extends ObjectCollection implements CakeEventListener {

/**

 * View object to use when making helpers.

 *

 * @var View

 */

	protected $_View;

/**

 * Constructor

 *

 * @param View $view View instance.

 */

	public function __construct(View $view) {

		$this->_View = $view;

	}

/**

 * Tries to lazy load a helper based on its name, if it cannot be found

 * in the application folder, then it tries looking under the current plugin

 * if any

 *

 * @param string $helper The helper name to be loaded

 * @return bool whether the helper could be loaded or not

 * @throws MissingHelperException When a helper could not be found.

 *    App helpers are searched, and then plugin helpers.

 */

	public function __isset($helper) {

		if (parent::__isset($helper)) {

			return true;

		}

		try {

			$this->load($helper);

		} catch (MissingHelperException $exception) {

			if ($this->_View->plugin) {

				$this->load($this->_View->plugin . '.' . $helper);

				return true;

			}

		}

		if (!empty($exception)) {

			throw $exception;

		}

		return true;

	}

/**

 * Provide public read access to the loaded objects

 *

 * @param string $name Name of property to read

 * @return mixed

 */

	public function __get($name) {

		if ($result = parent::__get($name)) {

			return $result;

		}

		if ($this->__isset($name)) {

			return $this->_loaded[$name];

		}

		return null;

	}

/**

 * Loads/constructs a helper. Will return the instance in the registry if it already exists.

 * By setting `$enable` to false you can disable callbacks for a helper. Alternatively you

 * can set `$settings['enabled'] = false` to disable callbacks. This alias is provided so that when

 * declaring $helpers arrays you can disable callbacks on helpers.

 *

 * You can alias your helper as an existing helper by setting the 'className' key, i.e.,

 * ```

 * public $helpers = array(

 *   'Html' => array(

 *     'className' => 'AliasedHtml'

 *   );

 * );

 * ```

 * All calls to the `Html` helper would use `AliasedHtml` instead.

 *

 * @param string $helper Helper name to load

 * @param array $settings Settings for the helper.

 * @return Helper A helper object, Either the existing loaded helper or a new one.

 * @throws MissingHelperException when the helper could not be found

 */

	public function load($helper, $settings = array()) {

		if (isset($settings['className'])) {

			$alias = $helper;

			$helper = $settings['className'];

		}

		list($plugin, $name) = pluginSplit($helper, true);

		if (!isset($alias)) {

			$alias = $name;

		}

		if (isset($this->_loaded[$alias])) {

			return $this->_loaded[$alias];

		}

		$helperClass = $name . 'Helper';

		App::uses($helperClass, $plugin . 'View/Helper');

		if (!class_exists($helperClass)) {

			throw new MissingHelperException(array(

				'class' => $helperClass,

				'plugin' => substr($plugin, 0, -1)

			));

		}

		$this->_loaded[$alias] = new $helperClass($this->_View, $settings);

		$vars = array('request', 'theme', 'plugin');

		foreach ($vars as $var) {

			$this->_loaded[$alias]->{$var} = $this->_View->{$var};

		}

		$enable = isset($settings['enabled']) ? $settings['enabled'] : true;

		if ($enable) {

			$this->enable($alias);

		}

		return $this->_loaded[$alias];

	}

/**

 * Returns a list of all events that will fire in the View during it's lifecycle.

 *

 * @return array

 */

	public function implementedEvents() {

		return array(

			'View.beforeRenderFile' => 'trigger',

			'View.afterRenderFile' => 'trigger',

			'View.beforeRender' => 'trigger',

			'View.afterRender' => 'trigger',

			'View.beforeLayout' => 'trigger',

			'View.afterLayout' => 'trigger'

		);

	}

/**

 * Trigger a callback method on every object in the collection.

 * Used to trigger methods on objects in the collection. Will fire the methods in the

 * order they were attached.

 *

 * ### Options

 *

 * - `breakOn` Set to the value or values you want the callback propagation to stop on.

 *    Can either be a scalar value, or an array of values to break on. Defaults to `false`.

 *

 * - `break` Set to true to enabled breaking. When a trigger is broken, the last returned value

 *    will be returned. If used in combination with `collectReturn` the collected results will be returned.

 *    Defaults to `false`.

 *

 * - `collectReturn` Set to true to collect the return of each object into an array.

 *    This array of return values will be returned from the trigger() call. Defaults to `false`.

 *

 * - `modParams` Allows each object the callback gets called on to modify the parameters to the next object.

 *    Setting modParams to an integer value will allow you to modify the parameter with that index.

 *    Any non-null value will modify the parameter index indicated.

 *    Defaults to false.

 *

 * @param string|CakeEvent $callback Method to fire on all the objects. Its assumed all the objects implement

 *   the method you are calling. If an instance of CakeEvent is provided, then then Event name will parsed to

 *   get the callback name. This is done by getting the last word after any dot in the event name

 *   (eg. `Model.afterSave` event will trigger the `afterSave` callback)

 * @param array $params Array of parameters for the triggered callback.

 * @param array $options Array of options.

 * @return mixed Either the last result or all results if collectReturn is on.

 * @throws CakeException when modParams is used with an index that does not exist.

 */

	public function trigger($callback, $params = array(), $options = array()) {

		if ($callback instanceof CakeEvent) {

			$callback->omitSubject = true;

		}

		return parent::trigger($callback, $params, $options);

	}

}