<?php
/**
* @version		$Id:database.php 6961 2007-03-15 16:06:53Z tcp $
* @package		Joomla.Framework
* @subpackage	Session
* @copyright	Copyright (C) 2005 - 2010 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();

/**
* Database session storage handler for PHP
*
* @package		Joomla.Framework
* @subpackage	Session
* @since		1.5
* @see http://www.php.net/manual/en/function.session-set-save-handler.php
*/
class JSessionStorageDatabase extends JSessionStorage
{
	var $_data = null;

	/**
	 * Open the SessionHandler backend.
	 *
	 * @access public
	 * @param string $save_path     The path to the session object.
	 * @param string $session_name  The name of the session.
	 * @return boolean  True on success, false otherwise.
	 */
	function open($save_path, $session_name)
	{
		return true;
	}

	/**
	 * Close the SessionHandler backend.
	 *
	 * @access public
	 * @return boolean  True on success, false otherwise.
	 */
	function close()
	{
		return true;
	}

 	/**
 	 * Read the data for a particular session identifier from the
 	 * SessionHandler backend.
 	 *
 	 * @access public
 	 * @param string $id  The session identifier.
 	 * @return string  The session data.
 	 */
	function read($id)
	{
		$db =& JFactory::getDBO();
		if(!$db->connected()) {
			return false;
		}

		$session = & JTable::getInstance('session');
		$session->load($id);
		return (string)$session->data;
	}

	/**
	 * Write session data to the SessionHandler backend.
	 *
	 * @access public
	 * @param string $id            The session identifier.
	 * @param string $session_data  The session data.
	 * @return boolean  True on success, false otherwise.
	 */
	function write($id, $session_data)
	{
		$db =& JFactory::getDBO();
		if(!$db->connected()) {
			return false;
		}

		$session = & JTable::getInstance('session');
		if ($session->load($id)) {
			$session->data = $session_data;
			$session->store();
		} else {
			// if load failed then we assume that it is because
			// the session doesn't exist in the database
			// therefore we use insert instead of store
			$app = &JFactory::getApplication();
			$session->data = $session_data;
			$session->insert($id, $app->getClientId());
		}

		return true;
	}

	/**
	  * Destroy the data for a particular session identifier in the
	  * SessionHandler backend.
	  *
	  * @access public
	  * @param string $id  The session identifier.
	  * @return boolean  True on success, false otherwise.
	  */
	function destroy($id)
	{
		$db =& JFactory::getDBO();
		if(!$db->connected()) {
			return false;
		}

		$session = & JTable::getInstance('session');
		$session->delete($id);
		return true;
	}

	/**
	 * Garbage collect stale sessions from the SessionHandler backend.
	 *
	 * @access public
	 * @param integer $maxlifetime  The maximum age of a session.
	 * @return boolean  True on success, false otherwise.
	 */
	function gc($maxlifetime)
	{
		$db =& JFactory::getDBO();
		if(!$db->connected()) {
			return false;
		}

		$session = & JTable::getInstance('session');
		$session->purge($maxlifetime);
		return true;
	}
}