protected function createSequenceNumber() : int
    {
        $session = $this->request->session();

        $value = random_int(100, 10000);
        $add = random_int(10, 1000);

        $session->put(self::SESSION_KEY, [
            'value'     => $value,
            'add'       => $add,
            'total'     => $value,
            // TODO Url referer?
        ]);

        return $value;
    }