function crumbleCookie(a) {
    for (var d = document.cookie.split(";"), c = {}, b = 0; b < d.length; b++) {
        var e = d[b].substring(0, d[b].indexOf("=")).trim(),
            i = d[b].substring(d[b].indexOf("=") + 1, d[b].length).trim();
        c[e] = i
    }
    if (a) return c[a] ? c[a] : null;
    return c
}

function bakeCookie(a, d, c, b, e, i) {
    var j = new Date;
    j.setTime(j.getTime());
    c && (c *= 864E5);
    j = new Date(j.getTime() + c);
    document.cookie = a + "=" + escape(d) + (c ? ";expires=" + j.toGMTString() : "") + (b ? ";path=" + b : "") + (e ? ";domain=" + e : "") + (i ? ";secure" : "")
}

function writeLogic(n) {
    var a = getTrafficSource(n, '.example.com');  //Insert your domain here
    
    a = a.replace(/\|{2,}/g, "|");
    a = a.replace(/^\|/, "");
    a = unescape(a);
    
    bakeCookie(n, a, 182, "/", "", "")		//Cookie expiration sets to 182 days
};

function getParam(s, q) {
  try{
      var match = s.match('[?&]' + q + '=([^&]+)');
      return match ? match[1] : '';
//        return s.match(RegExp('(^|&)'+q+'=([^&]*)'))[2];
  } catch(e){
    return '';    
  }
}

function calculateTrafficSource() {
  var source='', medium='', campaign='', term='', content='';
  var search_engines = [['bing', 'q'], ['google', 'q'], ['yahoo', 'q'], ['baidu', 'q'], ['yandex', 'q'], ['ask', 'q']];	//List of search engines
  var ref = document.referrer;
  ref = ref.substr(ref.indexOf('//')+2);
  ref_domain = ref;
  ref_path = '/';
  ref_search = '';
  
  // Checks for campaign parameters
  var url_search = document.location.search;
  
//      console.log(url_search.indexOf('utm_source'));
//      console.log(getParam(url_search, 'gclid'));
//      console.log(url_search);
  
  if(url_search.indexOf('utm_source') > -1) {
    source   = getParam(url_search, 'utm_source');
    medium   = getParam(url_search, 'utm_medium');
    campaign = getParam(url_search, 'utm_campaign');
    term     = getParam(url_search, 'utm_term');
    content  = getParam(url_search, 'utm_content');
  } 
  else if (getParam(url_search, 'gclid')) {
    source = 'google';
    medium = 'cpc';
    campaign = '(not set)';
  } 
  else if(ref) {
 
    // separate domain, path and query parameters
    if (ref.indexOf('/') > -1) {
      ref_domain = ref.substr(0,ref.indexOf('/'));
      ref_path = ref.substr(ref.indexOf('/'));
      if (ref_path.indexOf('?') > -1) {
        ref_search = ref_path.substr(ref_path.indexOf('?')+1);
        ref_path = ref_path.substr(0, ref_path.indexOf('?'));
      }
    }
    medium = 'referral';
    source = ref_domain;                      
    // Extract term for organic source
    for (var i=0; i<search_engines.length; i++){
      if(ref_domain.indexOf(search_engines[i][0]) > -1){
        medium = 'organic';
        source = search_engines[i][0];
        term = getParam(ref_search, search_engines[i][1]) || '(not provided)';
        break;
      } 
    }
  }
 
  return {
    'source'  : source,
    'medium'  : medium,
    'campaign': campaign,
    'term'    : term,
    'content' : content
  };
}

function getTrafficSource(cookieName, hostname) {
  var trafficSources = calculateTrafficSource();
  var source = trafficSources.source.length === 0 ? 'direct' : trafficSources.source;
  var medium = trafficSources.medium.length === 0 ? 'none' : trafficSources.medium;
  var campaign = trafficSources.campaign.length === 0 ? 'direct' : trafficSources.campaign;
  // exception
  if(medium === 'referral') {
      campaign = '';
  }
  var rightNow = new Date();
  var value = 'source='   + source +
              '&medium='  + medium +
              '&campaign='+ campaign +
              '&term='    + trafficSources.term +
              '&content=' + trafficSources.content +
              '&date='    + rightNow.toISOString().slice(0,10).replace(/-/g,"");
    return value;
}
  
// Self-invoking function
(function(){
	var date = new Date();	
	var fr_date = date.getUTCFullYear().toString() + ((date.getUTCMonth() < 9) ? '0' + (date.getUTCMonth()+1).toString() : (date.getUTCMonth()+1).toString()) + ((date.getUTCDate() < 10) ? '0' + date.getUTCDate().toString() : date.getUTCDate().toString());
	var session = crumbleCookie()['FirstSession'];

	if (typeof session == 'undefined')	// First time session
	{
		writeLogic('FirstSession');		
	}
    else {
		writeLogic('ReturningSession');		
    }
})();