<?php
/*
    DOKEOS - elearning and course management software

    For a full list of contributors, see documentation/credits.html

    This program is free software; you can redistribute it 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.
    See "documentation/licence.html" more details.

    Contact:
		Dokeos
		Rue des Palais 44 Paleizenstraat
		B-1030 Brussels - Belgium
		Tel. +32 (2) 211 34 56
*/


/**
*	Code library for HotPotatoes integration.
*	@package dokeos.exercise
* 	@author Istvan Mandak
* 	@version $Id: hotpotatoes.lib.php 10789 2007-01-18 19:18:27Z pcool $
*/



$dbTable     = Database::get_course_table(TABLE_DOCUMENT);

/**
 * Creates a hotpotato directory
 *
 * If a directory of that name already exists, don't create any. If a file of that name exists, remove it and create a directory
 * @param	string	Wanted path
 * @return boolean	Always true so far
 */
function hotpotatoes_init($baseWorkDir)
{
	//global $_course, $_user;
	$documentPath=$baseWorkDir.'/';
	if (!is_dir($documentPath))
	{
		if (is_file($documentPath))
		{
			@unlink($documentPath);
		}
		@mkdir($documentPath);
		return true;
	}else{
		//if this directory already exists, return false
		return false;
	}
	//why create a .htaccess here?
	//if (!is_file($documentPath.".htacces"))
	//{
	//		if (!($fp = fopen($documentPath.".htaccess", "w"))) {
	//	}
	//	$str = "order deny,allow\nallow from all";
	//	if (!fwrite($fp,$str)) { }
	//}
}

/**
 * Gets the title of the quizz file given as parameter
 * @param	string	File name
 * @param	string	File path
 * @return	string	The exercise title
 */
function GetQuizName($fname,$fpath)
{

	$title = "";
	$title = GetComment($fname);

	if($title=="")
	{
		if (!($fp = fopen($fpath.$fname, "r"))) {
		//die("could not open Quiz input");
			return GetFileName($fname);
		}

		$contents = fread($fp, filesize($fpath.$fname));
		fclose($fp);

		$contents = strtolower($contents);

		$pattern = array ( 1 => "title>", 2 => "/title>");

		$s_contents = substr($contents,0,strpos($contents,$pattern["2"])-1);
		$e_contents = substr($s_contents,strpos($contents,$pattern["1"])+strlen($pattern["1"]),strlen($s_contents));

		$title = $e_contents;
	}
	return $title;

}

/**
 * Gets the comment about a file from the corresponding database record
 * @param	string	File path
 * @return	string	Comment from the database record
 */
function GetComment($path)
{
	global $dbTable;
	$query = "select comment from $dbTable where path='$path'";
	$result = api_sql_query($query,__FILE__,__LINE__);
	while($row = mysql_fetch_array($result))
	{
		return $row[0];
	}
	return "";
}

/**
 * Sets the comment in the database for a particular path
 * @param	string	File path
 * @param	string	Comment to set
 * @return	string	Result of the database operation (api_sql_query will output some message directly on error anyway)
 */
function SetComment($path,$comment)
{
	global $dbTable;
	$query = "update $dbTable set comment='$comment' where path='$path'";
	$result = api_sql_query($query,__FILE__,__LINE__);
	return "$result";
}

/**
 * Get the name of the file from a path (without the extension)
 *
 * This assumes the path is made of elements split by '/', not '\' or '\\'
 * @param	string	Path
 * @return	string	File name
 */
function GetFileName($fname)
{
	$name = explode('/',$fname);
	$name = $name[sizeof($name)-1];
	return $name;
}

/**
 * Reads the file contents into a string
 * @param	string	Urlencoded path
 * @return	string	The file contents
 */
function ReadFileCont($full_file_path)
{
	if (!($fp = fopen(urldecode($full_file_path), "r"))) {
//	if (!($fp = fopen($full_file_path, "r"))) {
		return "";
	}
	$contents = fread($fp, filesize($full_file_path));
	fclose($fp);
	return $contents;
}

/**
 * Writes the file contents into the file given
 * @param	string	Urlencoded path
 * @param 	string	The file contents
 */
function WriteFileCont($full_file_path,$content)
{
	if (!($fp = fopen(urldecode($full_file_path), "w"))) {
		//die("could not open Quiz input");
	}
	fwrite($fp,$content);
	fclose($fp);
}

/**
 * Gets the name of an img whose path is given (without directories or extensions)
 * @param	string	An image tag (<img src="...." ...>)
 * @return	string	The image file name or an empty string
 * @uses GetFileName No comment
 */
function GetImgName($imgtag)
{	// select src tag from img tag
	$match = array();
	//preg_match('/(src=(["\'])1.*(["\'])1)/i',$imgtag,$match);  		  //src
	preg_match('/src(\s)*=(\s)*[\'"]([^\'"]*)[\'"]/i',$imgtag,$match); //get the img src as contained between " or '
	//list($key,$srctag)=each($match);
	$src=$match[3];
	//$src = substr($srctag,5,(strlen($srctag)-7));
	if (stristr($src,"http")===false)															// valid or invalid image name
	{
		if($src=="")
		{
			return "";
		}
		else
		{
			$tmp_src = GetFileName($src) ;
			if ($tmp_src == "")
			{
				return $src;
			}
			else
			{
				return $tmp_src;
			}
		}
	}
	else //the img tag contained "http", which means it is probably external. Ignore it.
	{
		return "";
	}
}

/**
 * Gets the source path of an image tag
 * @param	string	An image tag
 * @return	string	The image source or ""
 */
function GetSrcName($imgtag)
{	// select src tag from img tag
	$match = array();
	preg_match("|(src=\".*\" )|U",$imgtag,$match);  		  //src
	list($key,$srctag)=each($match);
	$src = substr($srctag,5,(strlen($srctag)-7));
	if (stristr($src,"http")==false)															// valid or invalid image name
	{
		return $src;
	}
	else
	{
		return '';

	}
}

/**
 * Gets the image parameters from an image path
 * @param	string	File name
 * @param	string	File path
 * @param  reference	Reference to a list of image parameters (emptied, then used to return results)
 * @param	reference	Reference to a counter of images (emptied, then used to return results)
 */
function GetImgParams($fname,$fpath,&$imgparams,&$imgcount)
{	//select img tags from context
	$imgparams = array();
	//phpinfo();
	$contents = ReadFileCont("$fpath"."$fname");
	$matches = array();
	preg_match_all("(<img .*>)",$contents,$matches);
	$imgcount = 0;
	while (list($int,$match)=each($matches))
	{
		//each match consists of a key and a value
		while(list($key,$imgtag)=each($match))
		{
			$imgname = GetImgName($imgtag);
			if ($imgname!="" && !in_array($imgname,$imgparams)){
				array_push($imgparams,$imgname);  // name (+ type) of the images in the html test
				$imgcount = $imgcount + 1;   			// number of images in the html test
			}
		}
	}
}

/**
 * Generates a list of hidden fields with the image params given as parameter to this function
 * @param	array		List of image parameters
 * @return	string	String containing the hidden parameters built from the list given
 */
function GenerateHiddenList($imgparams)
{
	$list = "";
	if(is_array($imgparams)){
	   while (list($int,$string)=each($imgparams))
		{
			$list .= "<input type=\"hidden\" name=\"imgparams[]\" value=\"$string\" />\n";
		}
	}
	return $list;
}

/**
 * Searches for a node in the given array
 * @param	reference	Reference to the array to search
 * @param	string		Node we are looking for in the array
 * @return	mixed			Node name or false if not found
 */
function myarraysearch(&$array,$node)
{
	$match = FALSE;
	$tmp_array = array();
	for($i=0;$i<count($array);$i++)
	{
		if (!strcmp($array[$i],$node))
			{
				$match = $node;
			}
		else
			{ array_push($tmp_array,$array[$i]); }
	}
	$array = $tmp_array;
	return $match;
}

/**
 * Look for the image name into an array
 * @param	reference	Reference to an array to search
 * @param	string		String to look for
 * @return	mixed			String given if found, false otherwise
 * @uses		myarraysearch	This function is just an additional layer on the myarraysearch() function
 */
function CheckImageName(&$imgparams,$string)
{
	$checked = myarraysearch($imgparams,$string);
	return $checked;
}

/**
 * Replaces an image tag by ???
 * @param	string	The content to replace
 * @return	string	The modified content
 */
function ReplaceImgTag($content)
{
	$newcontent = $content;
	$matches = array();
	preg_match_all("(<img .*>)",$content,$matches);
	$imgcount = 0;
	while (list($int,$match)=each($matches))
	{
		while(list($key,$imgtag)=each($match))
		{
			$imgname = GetSrcName($imgtag);
			if ($imgname=="") {}								// valid or invalid image name
			else {

				$prehref = $imgname;
				$posthref = GetFileName($imgname);
				$newcontent = str_replace($prehref,$posthref,$newcontent);
			}
		}
	}
	return $newcontent;
}

/**
 * Fills the folder name up to a certain length with "0"
 * @param	string	Original folder name
 * @param	integer	Length to reach
 * @return	string	Modified folder name
 */
function FillFolderName($name,$nsize)
{
	$str = "";
	for($i=0;$i < $nsize-strlen($name);$i++)
	{
		$str .= "0";
	}
	$str .= $name;
	return $str;
}

/**
 * Generates the HotPotato folder tree
 * @param	string	Folder path
 * @return	string	Folder name (modified)
 */
function GenerateHpFolder($folder)
{
	$filelist = array();
	if ($dir = @opendir($folder)) {
		while (($file = readdir($dir)) !== false) {
			if ( $file != ".") {
				if ($file != "..")
				{
					$full_name = $folder."/".$file;
					if (is_dir($full_name))
					{
						$filelist[] = $file;
					}
			   }
			}
		}
	}
	$w = 0;
	do {
		$name = FillFolderName(mt_rand(1,99999),6);
		$checked = myarraysearch($filelist,$name);
		//as long as we find the name in the array, continue looping. As soon as we have a new element, quit
		if ($checked) { $w = 1;	}
		else { $w = 0; }
	} while ($w==1);

	return $name;
}

/**
 * Gets the folder name (strip down path)
 * @param	string	Path
 *	@return	string	Folder name stripped down
 */
function GetFolderName($fname)
{
	$name = explode('/',$fname);
	$name = $name[sizeof($name)-2];
	return $name;
}

/**
 * Gets the folder path (withouth the name of the folder itself) ?
 * @param	string	Path
 * @return	string	Path stripped down
 */
function GetFolderPath($fname)
{
	$str = "";
	$name = explode('/',$fname);
	for($i=0;$i < sizeof($name)-1; $i++)
		{ $str = $str.$name[$i]."/"; }
	return $str;
}

/**
 * Checks if there are subfolders
 * @param	string	Path
 * @return	integer	1 if a subfolder was found, 0 otherwise
 */
function CheckSubFolder($path)
{
	$folder = GetFolderPath($path);
	$dflag = 0;
	if ($dir = @opendir($folder)) {
		while (($file = readdir($dir)) !== false) {
			if ( $file != ".") {
				if ($file != "..") {
					$full_name = $folder."/".$file;
					if (is_dir($full_name)) {
						$dflag = 1;	// first directory
					}
				}
			}
		}
	}
	return $dflag;
}

/**
 * Hotpotato Garbage Collector
 * @param	string	Path
 * @param	integer	Flag
 * @param	integer	User id
 * @return	void	No return value, but echoes results
 */
function HotPotGCt($folder,$flag,$userID)
{ // Garbage Collector
	$filelist = array();
	if ($dir = @opendir($folder)) {
		while (($file = readdir($dir)) !== false) {
			if ( $file != ".") {
				if ($file != "..")
				{
					$full_name = $folder."/".$file;
					if (is_dir($full_name))
					{
						HotPotGCt($folder."/".$file,$flag,$userID);
					}
					else
					{
						$filelist[] = $file;
					}
			   }
			}
		}
		closedir($dir);
	}
	while (list ($key, $val) = each ($filelist))
	{
		if (stristr($val,$userID.".t.html"))
		{
			if ($flag == 1)
			{
				my_delete($folder."/".$val);
			}
			else
			{
				echo $folder."/".$val."<br />";
			}
		}
	}
}
?>
