Facebook Custom Event - UTM Tracking - Last Attribution

UTM-Facebook-LA

/* UTM Tracking - Last Attribution - Facebook
 * @Ritwikga
 * Digishuffle
 */
  
var cookie_name = 'fb_utm'     //Name of Cookie
var cookie_duration = 180   //days

if(/utm_source/g.exec(location.search) && /utm_medium/g.exec(location.search))
{
cookieModify(cookie_name, true)
} else {cookieModify(cookie_name, false)}

function cookieModify(cookie_name, utms)
{  
if(utms)
{
var source = /utm_source=([^&]+)/g.exec(location.search)[1]
var medium = /utm_medium=([^&]+)/g.exec(location.search)[1]
var campaign = /utm_campaign=([^&]+)/g.exec(location.search)?/utm_campaign=([^&]+)/g.exec(location.search)[1]:undefined

fbq('trackCustom','UTMs',{'Source': source ,'Medium': medium, 'Campaign': campaign })
if(readCookie(cookie_name) != null)
{eraseCookie(cookie_name)}
  
var cookie_value = 'utm_source='+source+'&utm_medium='+medium+'&utm_campaign='+campaign;
createCookie(cookie_name, cookie_value ,cookie_duration)
} else 
{
if(document.referrer.search(location.hostname) == -1 )
{  
var source = (document.referrer =="")?"direct" : document.referrer.replace(/(http|https):\/\/www\.|\//g,"") 
var medium = (source == "direct") ? "none" : "organic"
var campaign = undefined

fbq('trackCustom','UTMs',{'Source': source ,'Medium': medium, 'Campaign': campaign })  

if(readCookie(cookie_name) != null)
{eraseCookie(cookie_name)}

var cookie_value = 'utm_source='+source+'&utm_medium='+medium+'&utm_campaign='+campaign;
createCookie(cookie_name, cookie_value ,cookie_duration)
} else {
var old_utms = readCookie(cookie_name)
var source = /utm_source=([^&]+)/g.exec(old_utms)[1]
var medium = /utm_medium=([^&]+)/g.exec(old_utms)[1]
var campaign = /utm_campaign=([^&]+)/g.exec(old_utms)?/utm_campaign=([^&]+)/g.exec(old_utms)[1]:undefined
fbq('trackCustom','UTMs',{'Source': source ,'Medium': medium, 'Campaign': campaign }) 
}
  
}
  
}


// Source : https://www.quirksmode.org/js/cookies.html ///
function createCookie(name,value,days) {
	if (days) {
		var date = new Date();
		date.setTime(date.getTime()+(days*24*60*60*1000));
		var expires = "; expires="+date.toGMTString();
	}
	else var expires = "";
	document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(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;
}

function eraseCookie(name) {
	createCookie(name,"",-1);
}