/* 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") {
			//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;
	}
});