<?php

/**

 * SimplePie

 *

 * A PHP-Based RSS and Atom Feed Framework.

 * Takes the hard work out of managing a complete RSS/Atom solution.

 *

 * Copyright (c) 2004-2012, Ryan Parman, Geoffrey Sneddon, Ryan McCue, and contributors

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without modification, are

 * permitted provided that the following conditions are met:

 *

 * 	* Redistributions of source code must retain the above copyright notice, this list of

 * 	  conditions and the following disclaimer.

 *

 * 	* Redistributions in binary form must reproduce the above copyright notice, this list

 * 	  of conditions and the following disclaimer in the documentation and/or other materials

 * 	  provided with the distribution.

 *

 * 	* Neither the name of the SimplePie Team nor the names of its contributors may be used

 * 	  to endorse or promote products derived from this software without specific prior

 * 	  written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS

 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY

 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS

 * AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 *

 * @package SimplePie

 * @version 1.3.1

 * @copyright 2004-2012 Ryan Parman, Geoffrey Sneddon, Ryan McCue

 * @author Ryan Parman

 * @author Geoffrey Sneddon

 * @author Ryan McCue

 * @link http://simplepie.org/ SimplePie

 * @license http://www.opensource.org/licenses/bsd-license.php BSD License

 */

/**

 * Used to create cache objects

 *

 * This class can be overloaded with {@see SimplePie::set_cache_class()},

 * although the preferred way is to create your own handler

 * via {@see register()}

 *

 * @package SimplePie

 * @subpackage Caching

 */

class SimplePie_Cache

{

	/**

	 * Cache handler classes

	 *

	 * These receive 3 parameters to their constructor, as documented in

	 * {@see register()}

	 * @var array

	 */

	protected static $handlers = array(

		'mysql' => 'SimplePie_Cache_MySQL',

		'memcache' => 'SimplePie_Cache_Memcache',

	);

	/**

	 * Don't call the constructor. Please.

	 */

	private function __construct() { }

	/**

	 * Create a new SimplePie_Cache object

	 *

	 * @param string $location URL location (scheme is used to determine handler)

	 * @param string $filename Unique identifier for cache object

	 * @param string $extension 'spi' or 'spc'

	 * @return SimplePie_Cache_Base Type of object depends on scheme of `$location`

	 */

	public static function get_handler($location, $filename, $extension)

	{

		$type = explode(':', $location, 2);

		$type = $type[0];

		if (!empty(self::$handlers[$type]))

		{

			$class = self::$handlers[$type];

			return new $class($location, $filename, $extension);

		}

		return new SimplePie_Cache_File($location, $filename, $extension);

	}

	/**

	 * Create a new SimplePie_Cache object

	 *

	 * @deprecated Use {@see get_handler} instead

	 */

	public function create($location, $filename, $extension)

	{

		trigger_error('Cache::create() has been replaced with Cache::get_handler(). Switch to the registry system to use this.', E_USER_DEPRECATED);

		return self::get_handler($location, $filename, $extension);

	}

	/**

	 * Register a handler

	 *

	 * @param string $type DSN type to register for

	 * @param string $class Name of handler class. Must implement SimplePie_Cache_Base

	 */

	public static function register($type, $class)

	{

		self::$handlers[$type] = $class;

	}

	/**

	 * Parse a URL into an array

	 *

	 * @param string $url

	 * @return array

	 */

	public static function parse_URL($url)

	{

		$params = parse_url($url);

		$params['extras'] = array();

		if (isset($params['query']))

		{

			parse_str($params['query'], $params['extras']);

		}

		return $params;

	}

}