<?php
/**
 * @package     Joomla.Platform
 * @subpackage  Session
 *
 * @copyright   Copyright (C) 2005 - 2012 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

defined('JPATH_PLATFORM') or die;

/**
 * XCache session storage handler
 *
 * @package     Joomla.Platform
 * @subpackage  Session
 * @since       11.1
 */
class JSessionStorageXcache extends JSessionStorage
{
	/**
	 * Constructor
	 *
	 * @param   array  $options  Optional parameters.
	 *
	 * @since   11.1
	 * @throws  RuntimeException
	 */
	public function __construct($options = array())
	{
		if (!self::isSupported())
		{
			throw new RuntimeException('XCache Extension is not available', 404);
		}

		parent::__construct($options);
	}

	/**
	 * Read the data for a particular session identifier from the SessionHandler backend.
	 *
	 * @param   string  $id  The session identifier.
	 *
	 * @return  string  The session data.
	 *
	 * @since   11.1
	 */
	public function read($id)
	{
		$sess_id = 'sess_' . $id;

		// Check if id exists
		if (!xcache_isset($sess_id))
		{
			return;
		}

		return (string) xcache_get($sess_id);
	}

	/**
	 * Write session data to the SessionHandler backend.
	 *
	 * @param   string  $id            The session identifier.
	 * @param   string  $session_data  The session data.
	 *
	 * @return  boolean  True on success, false otherwise.
	 *
	 * @since   11.1
	 */
	public function write($id, $session_data)
	{
		$sess_id = 'sess_' . $id;
		return xcache_set($sess_id, $session_data, ini_get("session.gc_maxlifetime"));
	}

	/**
	 * Destroy the data for a particular session identifier in the SessionHandler backend.
	 *
	 * @param   string  $id  The session identifier.
	 *
	 * @return  boolean  True on success, false otherwise.
	 *
	 * @since   11.1
	 */
	public function destroy($id)
	{
		$sess_id = 'sess_' . $id;

		if (!xcache_isset($sess_id))
		{
			return true;
		}

		return xcache_unset($sess_id);
	}

	/**
	 * Test to see if the SessionHandler is available.
	 *
	 * @return boolean  True on success, false otherwise.
	 *
	 * @since   12.1
	 */
	static public function isSupported()
	{
		return (extension_loaded('xcache'));
	}
}