protected function getCookiesPrepared() {
        $cookies = [];
        if ($this->_cookies) {
            $request = $this->app->reqHelper;
            if ($request->enableCookieValidation) {
                if ($request->cookieValidationKey == '') {
                    throw new InvalidConfigException(get_class($request) . '::cookieValidationKey must be configured with a secret key.');
                }
                $validationKey = $request->cookieValidationKey;
            } else {
                $validationKey = null;
            }
            foreach ($this->getCookies() as $name => $cookie) {
                /** @var Cookie $cookie */
                $cookies[] = $cookie->getForHeader($validationKey);
            }
        }

        return $cookies;
    }