<?php

/* vim: set expandtab tabstop=4 shiftwidth=4: */

//+----------------------------------------------------------------------+

//| WAMP (XP-SP1/1.3.24/4.0.12/4.3.0)                                    |

//+----------------------------------------------------------------------+

//| Copyright (c) 1992-2003 Michael Wimmer                               |

//+----------------------------------------------------------------------+

//| I don't have the time to read through all the licences to find out   |

//| what the exactly say. But it's simple. It's free for non commercial  |

//| projects, but as soon as you make money with it, i want my share :-) |

//| (License : Free for non-commercial use)                              |

//+----------------------------------------------------------------------+

//| Authors: Michael Wimmer <flaimo@gmx.net>                             |

//+----------------------------------------------------------------------+

//

// $Id$



/**

* @package Cache

*/

/**

* Caching of generated html/text or images...

*

* User it like this:

* <code>

* if ($cache->isCached($cache_filename, 14) == true) {

*   echo $cache->returnCache($cache_filename, false, false);

* } else {

*   // create content here and fill $text with it

*   $cache->writeCache($cache_filename, $text, false);

* }

* </code>

*

* Tested with Apache 1.3.24 and PHP 4.2.3

*

* @desc Caching of generated html/text or images&#x2026;

* @access public

* @author Michael Wimmer <flaimo@gmx.net>

* @copyright Michael Wimmer

* @link http://www.flaimo.com/

* @package Cache

* @version 1.002

*/

class Cache {



	/*-------------------*/

	/* V A R I A B L E S */

	/*-------------------*/



	/**#@+

	* @var string

	* @access private

	*/

	/**

	* Directory where cached files are saved

	*

	* @desc Directory where cached files are saved

	*/

	var $cache_dir;



	/**

	* Default extention for cache files

	*

	* @desc Default extention for cache files

	*/

	var $ext = 'txt';



	/**

	* Default prefix for cache files

	*

	* @desc Default prefix for cache files

	*/

	var $prefix = '';

	/**#@-*/



	/*-----------------------*/

	/* C O N S T R U C T O R */

	/*-----------------------*/



	/**#@+

	* @access private

	*/

	/**

	* Constructor

	*

	* Only job is to set all the variablesnames

	*

	* @desc Constructor

	* @param (string) $cachedir  Directory where cached files are saved. If string is empty &#x201C;cached&#x201D; will be used

	* @return (void)

	*/

	function Cache($cachedir = '') {

		$this->cache_dir  = (string) ((strlen(trim($cachedir)) > 0) ? $cachedir : 'cached');

  		if ($this->checkCacheDir() == FALSE) {

			die('error creating cache directory');

		} // end if

	} // end constructor



	/*-------------------*/

	/* F U N C T I O N S */

	/*-------------------*/



	/**

	* Checks if the cache directory exists, else trys to create it

	*

	* @desc Checks if the cache directory exists, else trys to create it

	* @return boolean

	*/

	function checkCacheDir() {

		if (!is_dir($this->cache_dir)) {

			return (boolean) ((!mkdir($this->cache_dir, 0700)) ? FALSE : TRUE);

		} else {

			return (boolean) TRUE;

		} // end if

	} // end function



	/**

	* Encodes the temporary filename

	*

	* @desc Encodes the temporary filename

	* @param string $filename

	* @return string $filename  Encoded string

	* @see decodeFilename()

	*/

	function encodeFilename($filename) {

		//return $filename;

		return (string) md5($filename);

	} // end function



	/**

	* Decodes the temporary filename

	*

	* @desc Decodes the temporary filename

	* @param string $filename

	* @return string $filename  Decoded string

	* @see encodeFilename()

	*/

	function decodeFilename($filename) {

		return (string) $filename;

		//return (string) str_rot13($filename);

	} // end function



	/**

	* Sticks together filename + path

	*

	* @desc Sticks together filename + path

	* @param string $filename

	* @return string

	* @see returnCachePicturename()

	* @uses encodeFilename()

	*/

	function returnCacheFilename($filename) {

		return (string) $this->cache_dir . '/' . $this->prefix . $this->encodeFilename($filename) . '.' . $this->ext;

	} // end function



	/**

	* Sticks together filename + path

	*

	* @desc Sticks together filename + path

	* @param string $filename

	* @param string $filetype

	* @return string

	* @see returnCacheFilename()

	* @uses encodeFilename()

	*/

	function returnCachePicturename($filename, $filetype) {

		return (string) $this->cache_dir . '/' . $this->prefix . $this->encodeFilename($filename) . '.' . $filetype;

	} // end function



	/**

	* Delete old files

	*

	* @desc Delete old files

	* @param int $lastaccess  Minimum age of the files last accesstime (in seconds) before files get deleted

	* @param int $created  Minimum age of the files (in seconds) before files get deleted

	* @return void

	* @see writeCardFile()

	*/

	function deleteOldFiles($lastaccess = 300, $created = 300) {

		if (!is_int($lastaccess) || $lastaccess < 1) {

			$lastaccess = (int) 300;

		} // end if

		if (!is_int($created) || $created < 1) {

			$created = (int) 300;

		} // end if

		$handle = opendir($this->download_dir);

		while ($file = readdir($handle)) {

			if (!eregi("^\.{1,2}$",$file) && !is_dir($this->cache_dir . '/' . $file) && (((time() - filemtime($this->cache_dir . '/' . $file)) > $created) || (((time() - fileatime($this->cache_dir . '/' . $file)) > $lastaccess)))) {

				unlink($this->cache_dir . '/' . $file);

			} // end if

		} // end while

		closedir($handle);

		if (isset($handle)) {

			unset($handle);

		} // end if

		if (isset($file)) {

			unset($file);

		} // end if

	} // end function

	/**#@-*/



	/**#@+

	* @access public

	*/

	/**

	* Checks if a cache file is available and up to date

	*

	* @desc Checks if a cache file is available and up to date

	* @param string $file  Name of the cached file

	* @param int $time  Minimum time until cache file has to be renewed

	* @return boolean $cached

	* @see isPictureCached()

	* @uses returnCacheFilename()

	*/

	function isCached($file, $time = 30) {

		if (($filetime = @filemtime($this->returnCacheFilename($file))) == FALSE) {

		 	return (boolean) FALSE;

		} // end if

		if ((time() - $filetime) > $time) {

			return (boolean) FALSE;

		} // end if

		return (boolean) TRUE;

	} // end function



	/**

	* Checks if a picture is cached and up to date

	*

	* @desc Checks if a picture is cached and up to date

	* @param string $file  Name of the cached file

	* @param int $time  Minimum time until cache file has to be renewed

	* @param string $type  Type of picture

	* @return boolean $cached

	* @see isCached()

	* @uses returnCachePicturename()

	*/

	function isPictureCached($file, $time = 30, $type = 'png') {

		if (file_exists($this->returnCachePicturename($file, $type)) && (time() - filemtime($this->returnCachePicturename($file, $type)) < $time)) {

			return (boolean) TRUE;

		} // end if

		return (boolean) FALSE;

	} // end function



	/**

	* Returns a cached file

	*

	* @desc Returns a cached file

	* @param string $file  Name of the cached file

	* @param boolean $passthrough  Return cache into a variable or directly output it to the browser

	* @param boolean $binary  Whether file should be returned in binary mode or not

	* @return mixed $cache

	* @see returnPictureCache()

	* @uses returnCacheFilename()

	*/

	function returnCache($file, $passthrough = FALSE, $binary = FALSE) {

		$returntype = (($binary == FALSE) ? 'r' : 'rb');

		if ($passthrough == TRUE) {

			return readfile($this->returnCacheFilename($file), $returntype);

		} else {

			$handle = fopen($this->returnCacheFilename($file), $returntype);

			$cache = fgets($handle);

			fclose($handle);

			return $cache;

		} // end if

	} // end function



	/**

	* Returns a cached picture

	*

	* @desc Returns a cached picture

	* @param string $file  Name of the cached file

	* @param string $filetype  Type of picture (jpg|gif|png)

	* @param boolean $binary  Whether file should be returned in binary mode or not

	* @return string

	* @see returnCache()

	* @uses returnCachePicturename()

	*/

	function returnPictureCache($file, $filetype = 'png', $binary = FALSE) {

		$returntype = (($binary == FALSE) ? 'r' : 'rb');

		return readfile($this->returnCachePicturename($file, $filetype), $returntype);

	} // end function



	/**

	* Writes a cache file

	*

	* @desc Writes a cache file

	* @param string $file  Name of the cached file

	* @param mixed $content  Content that should be cached

	* @param boolean $binary  Whether file should be returned in binary mode or not

	* @return void

	* @see writePictureCache()

	* @uses returnCacheFilename()

	*/

	function writeCache($file, $content, $binary = FALSE) {

		$writetype = (($binary == FALSE) ? 'w' : 'wb');

		$handle = fopen($this->returnCacheFilename($file), $writetype);

		fputs($handle, $content);

		fclose($handle);

	} // end function



	/**

	* Caches a picture

	*

	* @desc Caches a picture

	* @param string $file  Name of the cached file

	* @param binary $picture  The created picture

	* @param string $filetype  Type of picture (jpg|gif|png)

	* @return void

	* @see writeCache()

	* @uses returnCachePicturename()

	*/

	function writePictureCache($file, $picture, $filetype = 'png') {

		if ($filetype == 'jpg') {

			imagejpeg($picture, $this->returnCachePicturename($file, $filetype));

		} elseif ($filetype == 'gif') {

			imagegif($picture, $this->returnCachePicturename($file, $filetype));

		} elseif ($filetype == 'png') {

			imagepng($picture, $this->returnCachePicturename($file, $filetype));

		} else {

			return (boolean) FALSE;

		} // end if

		return (boolean) TRUE;

	} // end function

	/**#@-*/

} // end class Cache

?>