php — сохранять в cookie gclid, utm-метки и параметр ga_cid из cookie _ga

$seo_params=array('ga_cid','gclid','utm_source','utm_medium','utm_campaign','utm_content','utm_term');
$seo_cookies=$seo_cookies_default=array();
foreach($seo_params as $sp){
	switch($sp){
		case 'gclid':
			$seo_cookies_default[$sp]='NULL';
		break;
		case 'utm_source':
			$seo_cookies_default[$sp]='direct';
		break;
		default:
			$seo_cookies_default[$sp]='none';
		break;
	}
}
$update_cookies=false;
if(isset($_GET['gclid'])&&$_GET['gclid']!=''){
	$update_cookies=true;
	foreach($seo_params as $sp){
		switch($sp){
			case 'gclid':
				$seo_cookies[$sp]=$_GET[$sp];
			break;
			case 'utm_source':
				$seo_cookies[$sp]='google';
			break;
			case 'utm_medium':
				$seo_cookies[$sp]='cpc';
			break;
			default:
				if(stristr($sp,'utm_')&&isset($_GET[$sp])&&$_GET[$sp]!=''){
					$seo_cookies[$sp]=$_GET[$sp];
				}
				else{
					$seo_cookies[$sp]='none';
				}
			break;
		}
	}
}
else{
	$is_utm=false;
	foreach($seo_params as $sp){
		if(stristr($sp,'utm_')&&isset($_GET[$sp])&&$_GET[$sp]!=''){
			$seo_cookies[$sp]=$_GET[$sp];
			$is_utm=true;
			$update_cookies=true;
		}
		else{
			$seo_cookies[$sp]='none';
		}
	}
	if(!$is_utm){
		$referer=$_SERVER['HTTP_REFERER'];
		if($referer!=''){
			$parse_referer=parse_url($referer);
			$referer_domain=$parse_referer['host'];
			if($referer_domain!=''&&$referer_domain!=$_SERVER['HTTP_HOST']){
				$update_cookies=true;
				$organics=array('google','yandex','bing');
				$is_organic=false;
				foreach($organics as $organic){
					if(stristr($referer_domain,$organic)){
						$is_organic=true;
						foreach($seo_params as $sp){
							switch($sp){
								case 'utm_source':
									$seo_cookies[$sp]=$organic;
								break;
								case 'utm_medium':
									$seo_cookies[$sp]='organic';
								break;
								default:
									if(stristr($sp,'utm_')){
										$seo_cookies[$sp]='none';
									}
								break;
							}
						}
					}
				}
				if(!$is_organic){
					foreach($seo_params as $sp){
						switch($sp){
							case 'utm_source':
								$seo_cookies[$sp]=$referer_domain;
							break;
							case 'utm_medium':
								$seo_cookies[$sp]='referral';
							break;
							default:
								if(stristr($sp,'utm_')){
									$seo_cookies[$sp]='none';
								}
							break;
						}
					}
				}
			}
		}
	}
}
if($_COOKIE['_ga']!=''){
	$ga_cookie_split=explode('.',$_COOKIE['_ga']);
	if($ga_cookie_split[2]&&$ga_cookie_split[3]){
		$ga_cid=$ga_cookie_split[2].'.'.$ga_cookie_split[3];
		$seo_cookies['ga_cid']=$ga_cid;
	}
}
foreach($seo_params as $sp){
	if($update_cookies||!isset($_COOKIE['local_'.$sp])||$sp=='ga_cid'){
		$cv=($seo_cookies[$sp]!='')?$seo_cookies[$sp]:$seo_cookies_default[$sp];
		setcookie('local_'.$sp,$cv,time()+31536000,'/',$_SERVER['HTTP_HOST']);
		$_COOKIE['local_'.$sp]=$cv;
	}
}
function add_seo_params_to_letter(){
	global $seo_params;
	$text='<hr/>';
	foreach($seo_params as $sp){
		$text.=$sp.': '.$_COOKIE['local_'.$sp]."<br/>";
	}
	return $text;
}

// /core/components/formit/model/formit/fihooks.class.php
public function email(array $fields=array()){
	// ...
	$message.=add_seo_params_to_letter();
	// ...
}