Conimar tracking campaign parameters from URL trough forms

campaign_tracking.js

var queryForm = function(settings){
  var utm_data = ['utm_source','utm_medium','utm_campaign','utm_term','utm_content'];
  var reset = settings && settings.reset ? settings.reset : false;
  var self = window.location.toString();
  var querystring = self.split("?");
  if (querystring.length > 1) {
    var pairs = querystring[1].split("&");
    for (i in pairs) {
      var keyval = pairs[i].split("=");
      var supported_params = utm_data.indexOf(keyval[0]) !=-1;
      var paramval = decodeURIComponent(keyval[1]);
      console.log('parameter',keyval[0], supported_params, paramval);
      if ( (reset || sessionStorage.getItem('wwlc_cf_'+keyval[0]) === null) && supported_params) {
        sessionStorage.setItem('wwlc_cf_'+keyval[0], paramval);
      }
    }
  }
  var hiddenFields = document.querySelectorAll("input[type=hidden]");
  if(document.getElementById('wwlc-registration-form')){
	  for (var i=0; i<hiddenFields.length; i++) {
	    var param = sessionStorage.getItem('wwlc_cf_'+hiddenFields[i].name);
	    if (param && document.getElementById('wwlc_cf_'+hiddenFields[i].name) ) document.getElementById(''+hiddenFields[i].name).value = param;
	  }
	}
}
queryForm({'reset':true});