<?php
/**
 * Cache engine For XOOPS
 *
 * You may not change or alter any portion of this comment or credits
 * of supporting developers from this source code or any supporting source code
 * which is considered copyrighted (c) material of the original comment or credit authors.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * @copyright       The XOOPS Project http://sourceforge.net/projects/xoops/
 * @license         http://www.fsf.org/copyleft/gpl.html GNU public license
 * @package         class
 * @subpackage      cache
 * @since           2.3.0
 * @author          Taiwen Jiang <phppp@users.sourceforge.net>
 * @version         $Id: model.php 4897 2010-06-19 02:55:48Z phppp $
 */
defined('XOOPS_ROOT_PATH') or die('Restricted access');

/**
 * Database Storage engine for cache
 *
 *
 * PHP versions 4 and 5
 *
 * CakePHP(tm) :  Rapid Development Framework <http://www.cakephp.org/>
 * Copyright 2005-2008, Cake Software Foundation, Inc.
 *                                     1785 E. Sahara Avenue, Suite 490-204
 *                                     Las Vegas, Nevada 89104
 *
 * Licensed under The MIT License
 * Redistributions of files must retain the above copyright notice.
 *
 * @filesource
 * @copyright Copyright 2005-2008, Cake Software Foundation, Inc.
 * @link http://www.cakefoundation.org/projects/info/cakephp CakePHP(tm) Project
 * @package cake
 * @subpackage cake.cake.libs.cache
 * @since CakePHP(tm) v 1.2.0.4933
 * @version $Revision: 6311 $
 * @modifiedby $LastChangedBy: phpnut $
 * @lastmodified $Date: 2008-01-02 00:33:52 -0600 (Wed, 02 Jan 2008) $
 * @license http://www.opensource.org/licenses/mit-license.php The MIT License
 */
/**
 * Database Storage engine for cache
 *
 * @package cake
 * @subpackage cake.cake.libs.cache
 */
class XoopsCacheModel extends XoopsCacheEngine
{
    /**
     * settings
     *              className = name of the model to use, default => Cache
     *              fields = database fields that hold data and ttl, default => data, expires
     *
     * @var array
     * @access public
     */
    var $settings = array();

    /**
     * Model instance.
     *
     * @var object
     * @access private
     */
    var $model = null;

    /**
     * Model instance.
     *
     * @var object
     * @access private
     */
    var $fields = array();

    /**
     * Initialize the Cache Engine
     *
     * Called automatically by the cache frontend
     * To reinitialize the settings call Cache::engine('EngineName', [optional] settings = array());
     *
     * @param array $setting array of setting for the engine
     * @return boolean True if the engine has been successfully initialized, false if not
     * @access public
     */
    function init($settings)
    {
        $xoopsDB =& XoopsDatabaseFactory::getDatabaseConnection();

        parent::init($settings);
        $defaults = array('fields' => array('data' , 'expires'));
        $this->settings = array_merge($defaults, $this->settings);
        $this->fields = $this->settings['fields'];
        $this->model = new XoopsCacheModelHandler($xoopsDB);
        return true;
    }

    /**
     * Garbage collection. Permanently remove all expired and deleted data
     *
     * @access public
     */
    function gc()
    {
        return $this->model->deleteAll(new Criteria($this->fields[1], time, '<= '));
    }

    /**
     * Write data for key into cache
     *
     * @param string $key Identifier for the data
     * @param mixed $data Data to be cached
     * @param integer $duration How long to cache the data, in seconds
     * @return boolean True if the data was succesfully cached, false on failure
     * @access public
     */
    function write($key, $data, $duration)
    {
        // if (isset($this->settings['serialize'])) {
        $data = serialize($data);
        // }
        if (! $data) {
            return false;
        }
        $cache_obj = $this->model->create();
        $cache_obj->setVar($this->model::KEYNAME, $key);
        $cache_obj->setVar($this->fields[0], $data);
        $cache_obj->setVar($this->fields[1], time() + $duration);
        return $this->model->insert($cache_obj);
    }

    /**
     * Read a key from the cache
     *
     * @param string $key Identifier for the data
     * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it
     * @access public
     */
    function read($key)
    {
        $criteria = new CriteriaCompo(new Criteria($this->model::KEYNAME, $key));
        $criteria->add(new Criteria($this->fields[1], time(), ">"));
        $criteria->setLimit(1);
        $data = $this->model->getAll($criteria);
        if (!$data) {
            return null;
        }
        return unserialize($data[0]);
    }

    /**
     * Delete a key from the cache
     *
     * @param string $key Identifier for the data
     * @return boolean True if the value was succesfully deleted, false if it didn't exist or couldn't be removed
     * @access public
     */
    function delete($key)
    {
        return $this->model->delete($key);
    }

    /**
     * Delete all keys from the cache
     *
     * @return boolean True if the cache was succesfully cleared, false otherwise
     * @access public
     */
    function clear()
    {
        return $this->model->deleteAll();
    }
}

/**
 * XoopsCacheModelObject
 *
 * @package
 * @author John
 * @copyright Copyright (c) 2009
 * @version $Id: model.php 4897 2010-06-19 02:55:48Z phppp $
 * @access public
 */
class XoopsCacheModelObject extends XoopsObject
{
    function XoopsCacheModelObject()
    {
        $this->__construct();
    }

    function __construct()
    {
        parent::__construct();
        $this->initVar('key', XOBJ_DTYPE_TXTBOX);
        $this->initVar('data', XOBJ_DTYPE_SOURCE);
        $this->initVar('expires', XOBJ_DTYPE_INT);
    }
}

/**
 * XoopsCacheModelHandler
 *
 * @package
 * @author John
 * @copyright Copyright (c) 2009
 * @version $Id: model.php 4897 2010-06-19 02:55:48Z phppp $
 * @access public
 */
class XoopsCacheModelHandler extends XoopsPersistableObjectHandler
{
    const TABLE = 'cache_model';
    const CLASSNAME = 'XoopsCacheModelObject';
    const KEYNAME = 'key';
}

?>