src/UtmCookie/UtmCookie.php
public static function init()
	{
		// if initializated, just return
		if (self::$utmCookie !== null) {
			return;
		}
		
		self::initStaticValues();

		// utm from _COOKIE
		$utmCookieFilter = filter_input(INPUT_COOKIE, self::$utmCookieName, FILTER_SANITIZE_STRING, FILTER_REQUIRE_ARRAY);
		if (false === is_array($utmCookieFilter)) {
			$utmCookieFilter = [];
		}
		$utmCookie = self::removeNullValues($utmCookieFilter);

		// utm from _GET
		$utmGetFilter = filter_input_array(
				INPUT_GET, 
				[
					'utm_campaign' => FILTER_SANITIZE_STRING, 
					'utm_medium'   => FILTER_SANITIZE_STRING, 
					'utm_source'   => FILTER_SANITIZE_STRING, 
					'utm_term'     => FILTER_SANITIZE_STRING, 
					'utm_content'  => FILTER_SANITIZE_STRING
				]
		);
		if (false === is_array($utmGetFilter)) {
			$utmGetFilter = [];
		}
		$utmGet = self::removeNullValues($utmGetFilter);
		
		if (count($utmGet) !== 0 && self::$overwrite === true) {
			$utmCookieSave = array_merge(self::$utmCookie, $utmGet);
		} else {
			$utmCookieSave = array_merge(self::$utmCookie, $utmCookie, $utmGet);
		}

		if (count($utmGet) !== 0) {
			self::save($utmCookieSave);
		} else {
			self::$utmCookie = $utmCookieSave;
		}
	}
public static function init()
	{
		// if initializated, just return
		if (self::$utmCookie !== null) {
			return;
		}
		
		self::initStaticValues();

		// utm from _COOKIE
		$utmCookieFilter = filter_input(INPUT_COOKIE, self::$utmCookieName, FILTER_SANITIZE_STRING, FILTER_REQUIRE_ARRAY);
		if (false === is_array($utmCookieFilter)) {
			$utmCookieFilter = [];
		}
		$utmCookie = self::removeNullValues($utmCookieFilter);

		// utm from _GET
		$utmGetFilter = filter_input_array(
				INPUT_GET, 
				[
					'utm_campaign' => FILTER_SANITIZE_STRING, 
					'utm_medium'   => FILTER_SANITIZE_STRING, 
					'utm_source'   => FILTER_SANITIZE_STRING, 
					'utm_term'     => FILTER_SANITIZE_STRING, 
					'utm_content'  => FILTER_SANITIZE_STRING
				]
		);
		if (false === is_array($utmGetFilter)) {
			$utmGetFilter = [];
		}
		$utmGet = self::removeNullValues($utmGetFilter);
		
		if (count($utmGet) !== 0 && self::$overwrite === true) {
			$utmCookieSave = array_merge(self::$utmCookie, $utmGet);
		} else {
			$utmCookieSave = array_merge(self::$utmCookie, $utmCookie, $utmGet);
		}

		if (count($utmGet) !== 0) {
			self::save($utmCookieSave);
		} else {
			self::$utmCookie = $utmCookieSave;
		}
	}
Initialize. Get values from _GET and _COOKIES and save to UtmCookie. Init self::$utmCookie value.

@return void