/*
 * Copyright (c) 2006-2007 Mathias Bank (http://www.mathias-bank.de)
 * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php) 
 * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
 * 
 * Version 2.1
 * 
 * Thanks to 
 * Hinnerk Ruemenapf - http://hinnerk.ruemenapf.de/ for bug reporting and fixing.
 * Tom Leonard for some improvements
 */
jQuery.fn.extend({
   /*
	* Returns get parameters.
	*
	* If the desired param does not exist, null will be returned
	*
	* To get the document params:
	* @example value = $(document).getUrlParam("paramName");
	* 
	* To get the params of a html-attribut (uses src attribute)
	* @example value = $('#imgLink').getUrlParam("paramName");
	*/
	getUrlParam: function(strParamName){
		strParamName = escape(unescape(strParamName));
		
		var returnVal = new Array();
		var qString = null;
		
		//if ($(this).attr("nodeName")=="#document") {
		if (typeof $(this).attr('src')== 'undefined' && typeof $(this).attr('href')=='undefined') {
			//document-handler
			if (window.location.search.search(strParamName) > -1 ){
				qString = window.location.search.substr(1,window.location.search.length).split("&");
			}
		}
		else if ($(this).attr("src")!="undefined") {
			var strHref = $(this).attr("src")
			if ( strHref.indexOf("?") > -1 ){
			var strQueryString = strHref.substr(strHref.indexOf("?")+1);
				qString = strQueryString.split("&");
			}
		}
		else if ($(this).attr("href")!="undefined") {
			var strHref = $(this).attr("href")
			if ( strHref.indexOf("?") > -1 ){
			var strQueryString = strHref.substr(strHref.indexOf("?")+1);
				qString = strQueryString.split("&");
			}
		}
		else {
			return null;
		}
		
		if (qString==null) return null;
		
		for (var i=0;i<qString.length; i++){
			if (escape(unescape(qString[i].split("=")[0])) == strParamName){
				returnVal.push(qString[i].split("=")[1]);
			}
		}
		if (returnVal.length==0) return null;
		else if (returnVal.length==1) return returnVal[0];
		else return returnVal;
	}
});