<?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_Broker {
  	protected $fast_cache;
  	protected $slow_cache;
  
  	public function __construct($fast_cache, $slow_cache) {
  		$this->fast_cache = $fast_cache;
  		$this->slow_cache = $slow_cache;
  	}
  
  	public function get($key) {
  		if ($r = $this->fast_cache->get($key)) {
  			return $r;
  		}
  		return $this->slow_cache->get($key);
  	}
  
  	public function set($key, $value, $ttl=0) {
  		if (!$this->fast_cache->set($key, $value, $ttl)) {
  			if ($this->fast_cache->hasKey($key)) {
  				$this->fast_cache->remove($key);
  			}
  			return $this->slow_cache->set($key, $value, $ttl);
  		}
  		return true;
  	}
  
  	public function hasKey($key) {
  		if ($this->fast_cache->hasKey($key)) {
  			return true;
  		}
  		return $this->slow_cache->hasKey($key);
  	}
  
  	public function remove($key) {
  		if ($this->fast_cache->remove($key)) {
  			return true;
  		}
  		return $this->slow_cache->remove($key);
  	}
  
  	public function clear($prefix='') {
  		$this->fast_cache->clear($prefix);
  		$this->slow_cache->clear($prefix);
  	}
  }