A small JS Script to add usual Google Analytics utm_ variables to outgoing links so you can track your referrers in NATS system.

GA_utm_to_Nats_JS

/* A small JS Script  to add usual Google Analytics utm_ variables to outgoing links so you can track your referrers in NATS system. This works only if NATS has Automatic Campaigns (autocampaigns) enabled:  http://wiki.toomuchmedia.com/index.php/Automatic_Campaigns  tags
NATS 4.1 also supports tags / autotags which can be handy to split utm_ parameters apart 

Sample outgoing affil link http://www.affiliate.com/?utm_source=TS&utm_campaign=Header	

author: transbetty@gmail.com, www.transbetty.com

This is client-side based solution as oposed to my original solution: https://gist.github.com/transbetty/e23f4277c48416173f6c which causes problmes with server-side solution.
*/

// get URL params with JS http://goo.gl/Yljccv
function getParameterByName(name) {
name = name.replace(/[\[]/, "\\[").replace(/[\]]/, "\\]");
var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
    results = regex.exec(location.search);
return results === null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
}
var myUtmSource = getParameterByName('utm_source');
var myUtmCampaign = getParameterByName('utm_campaign');
var myUtmMedium = getParameterByName('utm_medium');
//console.log (myUtmSource);
//console.log (myUtmCampaign);
//console.log (myUtmMedium);

// basic JS library from quirksmode http://goo.gl/7XJHS
// instead update with JS with domain settting http://goo.gl/muKhv9
var Cookie =
{
   set: function(name, value, days)
   {
      var domain, domainParts, date, expires, host;
      if (days)
      {
         date = new Date();
         date.setTime(date.getTime()+(days*24*60*60*1000));
         expires = "; expires="+date.toGMTString();
      }
      else
      {
         expires = "";
      }
      host = location.host;
      if (host.split('.').length === 1)
      {
         // no "." in a domain - it's localhost or something similar
         document.cookie = name+"="+value+expires+"; path=/";
      }
      else
      {
         // Remember the cookie on all subdomains.
          //
         // Start with trying to set cookie to the top domain.
         // (example: if user is on foo.com, try to set
         //  cookie to domain ".com")
         //
         // If the cookie will not be set, it means ".com"
         // is a top level domain and we need to
         // set the cookie to ".foo.com"
         domainParts = host.split('.');
         domainParts.shift();
         domain = '.'+domainParts.join('.');
         document.cookie = name+"="+value+expires+"; path=/; domain="+domain;
         // check if cookie was successfuly set to the given domain
         // (otherwise it was a Top-Level Domain)
         if (Cookie.get(name) == null || Cookie.get(name) != value)
         {
            // append "." to current domain
            domain = '.'+host;
            document.cookie = name+"="+value+expires+"; path=/; domain="+domain;
         }
      }
   },
   get: function(name)
   {
      var nameEQ = name + "=";
      var ca = document.cookie.split(';');
      for (var i=0; i < ca.length; i++)
      {
         var c = ca[i];
         while (c.charAt(0)==' ')
         {
            c = c.substring(1,c.length);
         }

         if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
      }
      return null;
   },
   erase: function(name)
   {
      Cookie.set(name, '', -1);
   }
};

// read GA cookie http://goo.gl/46vG4
function updateQueryStringParameter(uri, key, value) {
  var re = new RegExp("([?&])" + key + "=.*?(&|$)", "i");
  var separator = uri.indexOf('?') !== -1 ? "&" : "?";
  if (uri.match(re)) {
    return uri.replace(re, '$1' + key + "=" + value + '$2');
  }
  else {
    return uri + separator + key + "=" + value;
  }
}

// change URL inspired by http://goo.gl/pPFRnZ
/* is URL par present?
	- yes
		- add params to all urls
		- set cookie
	- no
		- check cookie new
		- check cookie old
		- add params to all urls from
			1. new cookie
			2. old cookie, delete old cookie
*/
function changeUrl() {
	var linkOutClass = 'linkOut';
	var cookieName = 'trackRefs';
	var cookieNameOld = 'trackSource';
	var cookieValue = myUtmSource + ',' + myUtmCampaign + ',' + myUtmMedium;
	var natsVariableString = '?autocamp=';
	if ( myUtmSource || myUtmCampaign || myUtmMedium ) {
		var allLinkoutLinks = document.getElementsByClassName(linkOutClass);
		for(var i = 0; i < allLinkoutLinks.length; i++) {
			allLinkoutLinks[i].href = allLinkoutLinks[i].href + natsVariableString + encodeURIComponent(myUtmSource+','+myUtmCampaign+ ',' + myUtmMedium);	
		}
		Cookie.set(cookieName,encodeURIComponent(cookieValue),30);
	} else {
		var cookieValue = Cookie.get(cookieName);
		var cookieValueOld = Cookie.get(cookieNameOld);
		if (cookieValue == undefined && cookieValueOld ) {
			cookieValue = cookieValueOld;
			Cookie.erase(cookieNameOld);
			Cookie.set(cookieName,cookieValue,30);
		}
		if (cookieValue) {
			var allLinkoutLinks = document.getElementsByClassName(linkOutClass);
			for(var i = 0; i < allLinkoutLinks.length; i++) {
				allLinkoutLinks[i].href = allLinkoutLinks[i].href + natsVariableString + cookieValue ;	
			}
		}
	}
}
changeUrl();