/****************************************************
     Author: Brian J Clifton, June 2008
     Url: http://www.advanced-web-metrics.com
     This script is free to use as long as this info is left in
     
     Script for tracking the first and last referrer of a visitor
     
     All scripts presented have been tested and validated by the author and are believed to be correct
     as of the date of publication or posting. The Google Analytics software on which they depend is 
     subject to change, however; and therefore no warranty is expressed or implied that they will
     work as described in the future. Always check the most current Google Analytics documentation.

****************************************************/

function _uGC(l,n,s) {
   // used to obtain a value form a string of key=value pairs
   if (!l || l=="" || !n || n=="" || !s || s=="") return "-";
   var i,i2,i3,c="-";
   i=l.indexOf(n);
   i3=n.indexOf("=")+1;
   if (i > -1) {
	  i2=l.indexOf(s,i); if (i2 < 0) { i2=l.length; }
	  c=l.substring((i+i3),i2);
   }
   return c;
}

function checkFirst(){
   // check if this is a first time visitor
   newVisitor = 0;
   var myCookie = " " + document.cookie + ";";
   var searchName = "__utma=";
   var startOfCookie = myCookie.indexOf(searchName)
   if (startOfCookie == -1) {   // i.e. first time visitor
	  newVisitor = 1;
   }
}

function grabReferrer(){
   // grab campaign and referrer info from the _utmz cookie
   if (newVisitor) {
	  var z = _uGC(document.cookie, "__utmz=", ";");
	  urchin_source = _uGC(z,"utmcsr=", "|");
	  urchin_medium = _uGC(z,"utmcmd=", "|");
	  urchin_term = _uGC(z,"utmctr=", "|");
	  urchin_content = _uGC(z,"utmcct=", "|");
	  urchin_campaign = _uGC(z,"utmccn=", "|");
	  var gclid = _uGC(z,"utmgclid=","|");
	  if (gclid) {
		 urchin_source = "google";
		 urchin_medium = "cpc";
	  }
	  pageTracker._setVar(urchin_term);
   }
}