<?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;
  
  /**
   * A simple filesystem cache.
   *
   * @author Kris Wallsmith <kris.wallsmith@gmail.com>
   */
  class FilesystemCache implements CacheInterface
  {
      private $dir;
  
      public function __construct($dir)
      {
          $this->dir = $dir;
      }
  
      public function has($key)
      {
          return file_exists($this->dir.'/'.$key);
      }
  
      public function get($key)
      {
          $path = $this->dir.'/'.$key;
  
          if (!file_exists($path)) {
              throw new \RuntimeException('There is no cached value for '.$key);
          }
  
          return file_get_contents($path);
      }
  
      public function set($key, $value)
      {
          if (!is_dir($this->dir) && false === @mkdir($this->dir, 0777, true)) {
              throw new \RuntimeException('Unable to create directory '.$this->dir);
          }
  
          $path = $this->dir.'/'.$key;
  
          if (false === @file_put_contents($path, $value)) {
              throw new \RuntimeException('Unable to write file '.$path);
          }
      }
  
      public function remove($key)
      {
          $path = $this->dir.'/'.$key;
  
          if (file_exists($path) && false === @unlink($path)) {
              throw new \RuntimeException('Unable to remove file '.$path);
          }
      }
  }