<?php

/**

 * @version		$Id: file.php 10071 2008-02-27 19:17:32Z ian $

 * @package		Joomla.Framework

 * @subpackage	Cache

 * @copyright	Copyright (C) 2005 - 2008 Open Source Matters. All rights reserved.

 * @license		GNU/GPL, see LICENSE.php

 * Joomla! is free software. This version may have been modified pursuant

 * to the GNU General Public License, and as distributed it includes or

 * is derivative of works licensed under the GNU General Public License or

 * other free or open source software licenses.

 * See COPYRIGHT.php for copyright notices and details.

 */



// Check to ensure this file is within the rest of the framework
defined('JPATH_BASE') or die();


/**

 * File cache storage handler

 *

 * @author		Louis Landry <louis.landry@joomla.org>

 * @package		Joomla.Framework

 * @subpackage	Cache

 * @since		1.5

 */

class JCacheStorageFile extends JCacheStorage

{

	/**

	* Constructor

	*

	* @access protected

	* @param array $options optional parameters

	*/

	function __construct( $options = array() )

	{

		parent::__construct($options);



		$config			=& JFactory::getConfig();

		$this->_root	= $options['cachebase'];

		$this->_hash	= $config->getValue('config.secret');

	}



	/**

	 * Get cached data from a file by id and group

	 *

	 * @access	public

	 * @param	string	$id			The cache data id

	 * @param	string	$group		The cache data group

	 * @param	boolean	$checkTime	True to verify cache time expiration threshold

	 * @return	mixed	Boolean false on failure or a cached data string

	 * @since	1.5

	 */

	function get($id, $group, $checkTime)

	{

		$data = false;



		$path = $this->_getFilePath($id, $group);

		clearstatcache();

		if (is_file($path)) {

			if ($checkTime) {

				if (@ filemtime($path) > $this->_threshold) {

					$data = file_get_contents($path);

				}

			} else {

				$data = file_get_contents($path);

			}

		}

		return $data;

	}



	/**

	 * Store the data to a file by id and group

	 *

	 * @access	public

	 * @param	string	$id		The cache data id

	 * @param	string	$group	The cache data group

	 * @param	string	$data	The data to store in cache

	 * @return	boolean	True on success, false otherwise

	 * @since	1.5

	 */

	function store($id, $group, $data)

	{

		$written	= false;

		$path		= $this->_getFilePath($id, $group);



		$fp = @fopen($path, "wb");

		if ($fp) {

			if ($this->_locking) {

				@flock($fp, LOCK_EX);

			}

			$len = strlen($data);

			@fwrite($fp, $data, $len);

			if ($this->_locking) {

				@flock($fp, LOCK_UN);

			}

			@fclose($fp);

			$written = true;

		}

		// Data integrity check

		if ($written && ($data == file_get_contents($path))) {

			return true;

		} else {

			return false;

		}

	}



	/**

	 * Remove a cached data file by id and group

	 *

	 * @access	public

	 * @param	string	$id		The cache data id

	 * @param	string	$group	The cache data group

	 * @return	boolean	True on success, false otherwise

	 * @since	1.5

	 */

	function remove($id, $group)

	{

		$path = $this->_getFilePath($id, $group);

		if (!@unlink($path)) {

			return false;

		}

		return true;

	}



	/**

	 * Clean cache for a group given a mode.

	 *

	 * group mode		: cleans all cache in the group

	 * notgroup mode	: cleans all cache not in the group

	 *

	 * @access	public

	 * @param	string	$group	The cache data group

	 * @param	string	$mode	The mode for cleaning cache [group|notgroup]

	 * @return	boolean	True on success, false otherwise

	 * @since	1.5

	 */

	function clean($group, $mode)

	{

		jimport('joomla.filesystem.folder');



		$return = true;

		$folder	= $group;



		if(trim($folder) == '') {

			$mode = 'notgroup';

		}



		switch ($mode)

		{

			case 'notgroup':

				$folders = JFolder::folders($this->_root);

				for ($i=0,$n=count($folders);$i<$n;$i++)

				{

					if ($folders[$i] != $folder) {

						$return |= JFolder::delete($this->_root.DS.$folders[$i]);

					}

				}

				break;

			case 'group':

			default:

				if (is_dir($this->_root.DS.$folder)) {

					$return = JFolder::delete($this->_root.DS.$folder);

				}

				break;

		}

		return $return;

	}



	/**

	 * Garbage collect expired cache data

	 *

	 * @access public

	 * @return boolean  True on success, false otherwise.

	 */

	function gc()

	{

		$result = true;

		// files older than lifeTime get deleted from cache

		if (!is_null($this->_lifeTime)) {

			$files = JFolder::files($this->_root, '.', true, true);

			for ($i=0,$n=count($files);$i<$n;$i++)

			{

				if (@ filemtime($files[$i]) < $this->_threshold) {

					$result |= JFile::delete($files[$i]);

				}

			}

		}

		return $result;

	}



	/**

	 * Test to see if the cache storage is available.

	 *

	 * @static

	 * @access public

	 * @return boolean  True on success, false otherwise.

	 */

	function test()

	{

		$config	=& JFactory::getConfig();

		$root	= $config->getValue('config.cache_path', JPATH_ROOT.DS.'cache');

		return is_writable($root);

	}



	/**

	 * Get a cache file path from an id/group pair

	 *

	 * @access	private

	 * @param	string	$id		The cache data id

	 * @param	string	$group	The cache data group

	 * @return	string	The cache file path

	 * @since	1.5

	 */

	function _getFilePath($id, $group)

	{

		$folder	= $group;

		$name	= md5($this->_application.'-'.$id.'-'.$this->_hash.'-'.$this->_language).'.cache';



		// If the folder doesn't exist try to create it

		if (!is_dir($this->_root.DS.$folder)) {

			@mkdir($this->_root.DS.$folder);

		}



		// Make sure the folder exists

		if (!is_dir($this->_root.DS.$folder)) {

			return false;

		}

		return $this->_root.DS.$folder.DS.$name;

	}

}