<?php
/**
 * @brief		Dummy Cache Class
 * @author		<a href='http://www.invisionpower.com'>Invision Power Services, Inc.</a>
 * @copyright	(c) 2001 - SVN_YYYY Invision Power Services, Inc.
 * @license		http://www.invisionpower.com/legal/standards/
 * @package		IPS Social Suite
 * @since		17 Sept 2013
 * @version		SVN_VERSION_NUMBER
 */

namespace IPS\Data\Cache;

/* To prevent PHP errors (extending class does not exist) revealing path */
if ( !defined( '\IPS\SUITE_UNIQUE_KEY' ) )
{
	header( ( isset( $_SERVER['SERVER_PROTOCOL'] ) ? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.0' ) . ' 403 Forbidden' );
	exit;
}

/**
 * Dummy Storage Class
 */
class _None extends \IPS\Data\Cache
{
	/**
	 * Constructor
	 *
	 * @param	array	$configuration	Configuration
	 * @return	void
	 * @note	Overridden for performance reasons
	 */
	public function __construct( $configuration )
	{
	}

	/**
	 * Magic Method: Get
	 *
	 * @param	string	$key	Key
	 * @return	string	Value from the _datastore
	 * @throws	\OutOfRangeException
	 * @note	Overridden for performance reasons
	 */
	public function __get( $key )
	{
		throw new \OutOfRangeException;
	}

	/**
	 * Magic Method: Set
	 *
	 * @param	string	$key	Key
	 * @param	string	$value	Value
	 * @return	void
	 * @note	Overridden for performance reasons
	 */
	public function __set( $key, $value )
	{
	}

	/**
	 * Magic Method: Isset
	 *
	 * @param	string	$key	Key
	 * @return	bool
	 * @note	Overridden for performance reasons
	 */
	public function __isset( $key )
	{
		return FALSE;
	}

	/**
	 * Magic Method: Unset
	 *
	 * @param	string	$key	Key
	 * @return	void
	 * @note	Overridden for performance reasons
	 */
	public function __unset( $key )
	{
	}

	/**
	 * Server supports this method?
	 *
	 * @return	bool
	 */
	public static function supported()
	{
		return TRUE;
	}
	
	/**
	 * Abstract Method: Get
	 *
	 * @param	string	$key	Key
	 * @return	string	Value from the _datastore
	 */
	protected function get( $key )
	{
		throw new \RuntimeException;
	}
	
	/**
	 * Abstract Method: Set
	 *
	 * @param	string	$key	Key
	 * @param	string	$value	Value
	 * @return	bool
	 */
	protected function set( $key, $value )
	{
		return FALSE;
	}
	
	/**
	 * Abstract Method: Exists?
	 *
	 * @param	string	$key	Key
	 * @return	bool
	 */
	protected function exists( $key )
	{
		return FALSE;
	}
	
	/**
	 * Abstract Method: Delete
	 *
	 * @param	string	$key	Key
	 * @return	bool
	 */
	protected function delete( $key )
	{
		return TRUE;
	}
	
	/**
	 * Abstract Method: Clear All Caches
	 *
	 * @return	void
	 */
	public function clearAll()
	{
		parent::clearAll();
		try
		{
			\IPS\Db::i()->delete( 'core_cache' );
		}
		catch ( \IPS\Db\Exception $e ){}
	}
}