<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

/**

 * CodeIgniter

 *

 * An open source application development framework for PHP 4.3.2 or newer

 *

 * @package		CodeIgniter

 * @author		ExpressionEngine Dev Team

 * @copyright	Copyright (c) 2006 - 2012 EllisLab, Inc.

 * @license		http://codeigniter.com/user_guide/license.html

 * @link		http://codeigniter.com

 * @since		Version 2.0

 * @filesource	

 */



// ------------------------------------------------------------------------



/**

 * CodeIgniter Memcached Caching Class 

 *

 * @package		CodeIgniter

 * @subpackage	Libraries

 * @category	Core

 * @author		ExpressionEngine Dev Team

 * @link		

 */



class CI_Cache_memcached extends CI_Driver {



	private $_memcached;	// Holds the memcached object



	protected $_memcache_conf 	= array(

					'default' => array(

						'default_host'		=> '127.0.0.1',

						'default_port'		=> 11211,

						'default_weight'	=> 1

					)

				);



	// ------------------------------------------------------------------------	



	/**

	 * Fetch from cache

	 *

	 * @param 	mixed		unique key id

	 * @return 	mixed		data on success/false on failure

	 */	

	public function get($id)

	{	

		$data = $this->_memcached->get($id);

		

		return (is_array($data)) ? $data[0] : FALSE;

	}



	// ------------------------------------------------------------------------



	/**

	 * Save

	 *

	 * @param 	string		unique identifier

	 * @param 	mixed		data being cached

	 * @param 	int			time to live

	 * @return 	boolean 	true on success, false on failure

	 */

	public function save($id, $data, $ttl = 60)

	{

		if (get_class($this->_memcached) == 'Memcached')

		{

			return $this->_memcached->set($id, array($data, time(), $ttl), $ttl);

		}

		else if (get_class($this->_memcached) == 'Memcache')

		{

			return $this->_memcached->set($id, array($data, time(), $ttl), 0, $ttl);

		}

		

		return FALSE;

	}



	// ------------------------------------------------------------------------

	

	/**

	 * Delete from Cache

	 *

	 * @param 	mixed		key to be deleted.

	 * @return 	boolean 	true on success, false on failure

	 */

	public function delete($id)

	{

		return $this->_memcached->delete($id);

	}



	// ------------------------------------------------------------------------

	

	/**

	 * Clean the Cache

	 *

	 * @return 	boolean		false on failure/true on success

	 */

	public function clean()

	{

		return $this->_memcached->flush();

	}



	// ------------------------------------------------------------------------



	/**

	 * Cache Info

	 *

	 * @param 	null		type not supported in memcached

	 * @return 	mixed 		array on success, false on failure

	 */

	public function cache_info($type = NULL)

	{

		return $this->_memcached->getStats();

	}



	// ------------------------------------------------------------------------

	

	/**

	 * Get Cache Metadata

	 *

	 * @param 	mixed		key to get cache metadata on

	 * @return 	mixed		FALSE on failure, array on success.

	 */

	public function get_metadata($id)

	{

		$stored = $this->_memcached->get($id);



		if (count($stored) !== 3)

		{

			return FALSE;

		}



		list($data, $time, $ttl) = $stored;



		return array(

			'expire'	=> $time + $ttl,

			'mtime'		=> $time,

			'data'		=> $data

		);

	}



	// ------------------------------------------------------------------------



	/**

	 * Setup memcached.

	 */

	private function _setup_memcached()

	{

		// Try to load memcached server info from the config file.

		$CI =& get_instance();

		if ($CI->config->load('memcached', TRUE, TRUE))

		{

			if (is_array($CI->config->config['memcached']))

			{

				$this->_memcache_conf = NULL;



				foreach ($CI->config->config['memcached'] as $name => $conf)

				{

					$this->_memcache_conf[$name] = $conf;

				}				

			}			

		}

		

		$this->_memcached = new Memcached();



		foreach ($this->_memcache_conf as $name => $cache_server)

		{

			if ( ! array_key_exists('hostname', $cache_server))

			{

				$cache_server['hostname'] = $this->_default_options['default_host'];

			}

	

			if ( ! array_key_exists('port', $cache_server))

			{

				$cache_server['port'] = $this->_default_options['default_port'];

			}

	

			if ( ! array_key_exists('weight', $cache_server))

			{

				$cache_server['weight'] = $this->_default_options['default_weight'];

			}

	

			$this->_memcached->addServer(

					$cache_server['hostname'], $cache_server['port'], $cache_server['weight']

			);

		}

	}



	// ------------------------------------------------------------------------





	/**

	 * Is supported

	 *

	 * Returns FALSE if memcached is not supported on the system.

	 * If it is, we setup the memcached object & return TRUE

	 */

	public function is_supported()

	{

		if ( ! extension_loaded('memcached'))

		{

			log_message('error', 'The Memcached Extension must be loaded to use Memcached Cache.');

			

			return FALSE;

		}

		

		$this->_setup_memcached();

		return TRUE;

	}



	// ------------------------------------------------------------------------



}

// End Class



/* End of file Cache_memcached.php */

/* Location: ./system/libraries/Cache/drivers/Cache_memcached.php */