--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/includes/cache.php	Mon Jul 07 18:12:30 2008 -0400
@@ -0,0 +1,131 @@
+<?php
+
+/*
+ * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between
+ * Version 1.1.4 (Caoineag alpha 4)
+ * Copyright (C) 2006-2008 Dan Fuhry
+ *
+ * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
+ *
+ * This program 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 General Public License for details.
+ */
+ 
+/**
+ * Framework for caching arbitrary data around the site.
+ * @package Enano
+ * @subpackage Core
+ * @author Dan Fuhry <dan@enanocms.org>
+ * @license GNU General Public License
+ */
+
+class CacheManager
+{
+  /**
+   * Fetch a cached piece of data.
+   * @param string Cache ID. The timestamp is checked automatically.
+   */
+  
+  public function fetch($cache_id)
+  {
+    if ( !preg_match('/^[a-z0-9_]+$/', $cache_id) )
+    {
+      throw new Exception('Cache ID must be letters, numbers, and underscores.');
+    }
+    $cache_file = ENANO_ROOT . "/cache/cache_$cache_id.php";
+    if ( file_exists($cache_file) )
+    {
+      require($cache_file);
+      if ( isset($_cache_data) && isset($_cache_ttl) && isset($_cache_timestamp) )
+      {
+        $cache_expire = $_cache_timestamp + ( 60 * $_cache_ttl);
+        if ( $cache_expire >= time() || $_cache_ttl === -1 )
+        {
+          return $_cache_data;
+        }
+      }
+    }
+    return false;
+  }
+  
+  /**
+   * Stores an array by var_export()ing it and saving it to disk.
+   * @param string Cache ID - human readable name for this store (letters, numbers, underscores)
+   * @param array Data to store
+   * @param int TTL for the cached array, in minutes. Defaults to 20. If set to -1, caches indefinitely.
+   * @return bool True on success, false on failure
+   */
+  
+  public function store($cache_id, $data, $ttl = 20)
+  {
+    if ( getConfig('cache_thumbs') != '1' )
+    {
+      // caching disabled
+      return false;
+    }
+    if ( !preg_match('/^[a-z0-9_]+$/', $cache_id) )
+    {
+      throw new Exception('Cache ID must be letters, numbers, and underscores.');
+    }
+    if ( !is_int($ttl) )
+    {
+      throw new Exception('TTL must be an integer');
+    }
+    
+    $cache_file = ENANO_ROOT . "/cache/cache_$cache_id.php";
+    if ( file_exists($cache_file) )
+    {
+      @unlink($cache_file);
+    }
+    $fh = @fopen($cache_file, 'w');
+    if ( !$fh )
+    {
+      throw new Exception('Failed to open file for writing.');
+    }
+    $exported = Language::var_export_string($data);
+    $now = time();
+    $content = <<<EOF
+<?php
+/**
+ * Automatically generated cache file.
+ * Do not edit this file as it will expire and be overwritten $ttl minutes from its creation.
+ */
+
+\$_cache_ttl = $ttl;
+\$_cache_timestamp = $now;
+\$_cache_data = $exported;
+
+EOF;
+    fwrite($fh, $content);
+    fclose($fh);
+    
+    return true;
+  }
+  
+  /**
+   * Deletes a cached item.
+   * @param string Cache ID.
+   * @return bool true on success or if item doesn't exist, false on failure
+   */
+  
+  public function purge($cache_id)
+  {
+    if ( !preg_match('/^[a-z0-9_]+$/', $cache_id) )
+    {
+      throw new Exception('Cache ID must be letters, numbers, and underscores.');
+    }
+    
+    $cache_file = ENANO_ROOT . "/cache/cache_$cache_id.php";
+    if ( file_exists($cache_file) )
+    {
+      if ( unlink($cache_file) )
+      {
+        return true;
+      }
+      return false;
+    }
+    return true;
+  }
+}
+