public static function getReferer($full = false) {
		$ref = env('HTTP_REFERER');
		$forwarded = env('HTTP_X_FORWARDED_HOST');
		if ($forwarded) {
			$ref = $forwarded;
		}
		if (empty($ref)) {
			return $ref;
		}
		if ($full) {
			$ref = Router::url($ref, $full);
		}
		return $ref;
	}