<?php
  /**
   * Copyright (c) 2012 Bart Visscher <bartv@thisnet.nl>
   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */
  
  class OC_Cache_XCache {
  	protected $prefix;
  
  	public function __construct($global = false) {
  		$this->prefix = OC_Util::getInstanceId().'/';
  		if (!$global) {
  			$this->prefix .= OC_User::getUser().'/';
  		}
  	}
  
  	/**
  	 * entries in XCache gets namespaced to prevent collisions between owncloud instances and users
  	 */
  	protected function getNameSpace() {
  		return $this->prefix;
  	}
  
  	public function get($key) {
  		return xcache_get($this->getNamespace().$key);
  	}
  
  	public function set($key, $value, $ttl=0) {
  		if($ttl>0) {
  			return xcache_set($this->getNamespace().$key, $value, $ttl);
  		}else{
  			return xcache_set($this->getNamespace().$key, $value);
  		}
  	}
  
  	public function hasKey($key) {
  		return xcache_isset($this->getNamespace().$key);
  	}
  
  	public function remove($key) {
  		return xcache_unset($this->getNamespace().$key);
  	}
  
  	public function clear($prefix='') {
  		if(!function_exists('xcache_unset_by_prefix')) {
  			function xcache_unset_by_prefix($prefix) {
  				// Since we can't clear targetted cache, we'll clear all. :(
  				xcache_clear_cache(XC_TYPE_VAR, 0);
  			}
  		}
  		xcache_unset_by_prefix($this->getNamespace().$prefix);
  		return true;
  	}
  }