<?php
  
  /*
   * This file is part of the Assetic package, an OpenSky project.
   *
   * (c) 2010-2014 OpenSky Project Inc
   *
   * For the full copyright and license information, please view the LICENSE
   * file that was distributed with this source code.
   */
  
  namespace Assetic\Cache;
  
  /**
   * Uses APC to cache files
   *
   * @author André Roaldseth <andre@roaldseth.net>
   */
  class ApcCache implements CacheInterface
  {
      public $ttl = 0;
  
      /**
       * @see CacheInterface::has()
       */
      public function has($key)
      {
          return apc_exists($key);
      }
  
      /**
       * @see CacheInterface::get()
       */
      public function get($key)
      {
          $value = apc_fetch($key, $success);
  
          if (!$success) {
              throw new \RuntimeException('There is no cached value for ' . $key);
          }
  
          return $value;
      }
  
      /**
       * @see CacheInterface::set()
       */
      public function set($key, $value)
      {
          $store = apc_store($key, $value, $this->ttl);
  
          if (!$store) {
              throw new \RuntimeException('Unable to store "' . $key . '" for ' . $this->ttl . ' seconds.');
          }
  
          return $store;
      }
  
      /**
       * @see CacheInterface::remove()
       */
      public function remove($key)
      {
          return apc_delete($key);
      }
  }