<?php
/*
 +--------------------------------------------------------------------+
| CiviCRM version 4.5                                                |
+--------------------------------------------------------------------+
| Copyright CiviCRM LLC (c) 2004-2014                                |
+--------------------------------------------------------------------+
| This file is a part of CiviCRM.                                    |
|                                                                    |
| CiviCRM is free software; you can copy, modify, and distribute it  |
| under the terms of the GNU Affero General Public License           |
| Version 3, 19 November 2007 and the CiviCRM Licensing Exception.   |
|                                                                    |
| CiviCRM is distributed in the hope that it will be useful, but     |
| WITHOUT ANY WARRANTY; without even the implied warranty of         |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.               |
| See the GNU Affero General Public License for more details.        |
|                                                                    |
| You should have received a copy of the GNU Affero General Public   |
| License and the CiviCRM Licensing Exception along                  |
| with this program; if not, contact CiviCRM LLC                     |
| at info[AT]civicrm[DOT]org. If you have questions about the        |
| GNU Affero General Public License or the licensing of CiviCRM,     |
| see the CiviCRM license FAQ at http://civicrm.org/licensing        |
+--------------------------------------------------------------------+
*/

/**
 * Class CRM_Utils_Cache_SerializeCache
 */
class CRM_Utils_Cache_SerializeCache implements CRM_Utils_Cache_Interface {

  /**
   * The cache storage container, an array by default, stored in a file under templates
   */
  private $_cache;

  /**
   * Constructor
   *
   * @param array $config an array of configuration params
   *
   * @return \CRM_Utils_Cache_SerializeCache
   */
  function __construct($config) {
    $this->_cache = array();
  }

  /**
   * @param $key
   *
   * @return string
   */
  function fileName ($key) {
    if (strlen($key) > 50)
      return CIVICRM_TEMPLATE_COMPILEDIR ."CRM_".md5($key).".php";
    return CIVICRM_TEMPLATE_COMPILEDIR .$key.".php";
  }

  /**
   * @param string $key
   *
   * @return mixed
   */
  function get ($key) {
    if (array_key_exists($key,$this->_cache))
      return $this->_cache[$key];

    if (!file_exists($this->fileName ($key))) {
      return;
    }
    $this->_cache[$key] = unserialize (substr (file_get_contents ($this->fileName ($key)),8));
    return $this->_cache[$key];
  }

  /**
   * @param string $key
   * @param mixed $value
   */
  function set($key, &$value) {
    if (file_exists($this->fileName ($key))) {
      return;
    }
    $this->_cache[$key] = $value;
    file_put_contents ($this->fileName ($key),"<?php //".serialize ($value));
  }

  /**
   * @param string $key
   */
  function delete($key) {
    if (file_exists($this->fileName ($key))) {
      unlink ($this->fileName ($key));
    }
    unset($this->_cache[$key]);
  }

  /**
   * @param null $key
   */
  function flush($key =null) {
    $prefix = "CRM_";
    if (!$handle = opendir(CIVICRM_TEMPLATE_COMPILEDIR)) {
      return; // die? Error?
    }
    while (false !== ($entry = readdir($handle))) {
      if (substr ($entry,0,4) == $prefix) {
        unlink (CIVICRM_TEMPLATE_COMPILEDIR.$entry);
      }
    }
    closedir($handle);
    unset($this->_cache);
    $this->_cache = array();
  }
}