/* 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++) {
		  
              var index = qString[i].indexOf("=");
              if (index >= 0) {
                  var strCurrentParamName = escape(unescape(qString[i].substr(0, index)));
                  if (strCurrentParamName == strParamName) {
                      returnVal.push(qString[i].substr(index + 1));
                  }
              }
          }

          if (returnVal.length==0) return null;
          else if (returnVal.length==1) return returnVal[0];
          else return returnVal;
        }
});