public function getLogoUrl()
    {
        $params = [
            'id'   => $this->_apiKey,
            'type' => $this->logoType,
            'cols' => (int)$this->logoCols,
            'text' => (int)$this->logoText,
            'auth' => $this->calculateLogoAuth(),
        ];

        return self::LOGO_BASE_URL . '?' . http_build_query($params);
    }