<?php
/**
 * SimplePie
 *
 * A PHP-Based RSS and Atom Feed Framework.
 * Takes the hard work out of managing a complete RSS/Atom solution.
 *
 * Copyright (c) 2004-2009, 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-dev
 * @copyright 2004-2010 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
 * @todo phpDoc comments
 */

class SimplePie_Cache_Memcache implements SimplePie_Cache_Base
{
	protected $cache;
	protected $options;
	protected $name;

	public function __construct($url, $filename, $extension)
	{
		$this->options = array(
			'host' => '127.0.0.1',
			'port' => 11211,
			'extras' => array(
				'timeout' => 3600, // one hour
				'prefix' => 'simplepie_',
			),
		);
		$this->options = array_merge_recursive($this->options, SimplePie_Cache::parse_URL($url));
		$this->name = $this->options['extras']['prefix'] . md5("$filename:$extension");

		$this->cache = new Memcache();
		$this->cache->addServer($this->options['host'], (int) $this->options['port']);
	}

	public function save($data)
	{
		if (is_a($data, 'SimplePie'))
		{
			$data = $data->data;
		}
		return $this->cache->set($this->name, serialize($data), MEMCACHE_COMPRESSED, (int) $this->options['extras']['timeout']);
	}

	public function load()
	{
		$data = $this->cache->get($this->name);

		if ($data !== false)
		{
			return unserialize($data);
		}
		return false;
	}

	public function mtime()
	{
		$data = $this->cache->get($this->name);

		if ($data !== false)
		{
			// essentially ignore the mtime because Memcache expires on it's own
			return time();
		}

		return false;
	}

	public function touch()
	{
		$data = $this->cache->get($this->name);

		if ($data !== false)
		{
			return $this->cache->set($this->name, $data, MEMCACHE_COMPRESSED, (int) $this->duration);
		}

		return false;
	}

	public function unlink()
	{
		return $this->cache->delete($this->name);
	}
}