TYPO3 Redirect to default page url if it is not translated

SiteLanguageRedirect.php

<?php

namespace PaulBeck\TueSitetemplate;

use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\MiddlewareInterface;
use Psr\Http\Server\RequestHandlerInterface;
use TYPO3\CMS\Core\Utility\GeneralUtility;

class SiteLanguageRedirect implements MiddlewareInterface
{
    /**
     * @var ServerRequestInterface
     */
    protected $request = null;

    /**
     * @param ServerRequestInterface $request
     * @param RequestHandlerInterface $handler
     * @return ResponseInterface
     */
    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
    {
        /** @var \TYPO3\CMS\Core\Http\Request request */
        $this->request = $request;

        /** @var \TYPO3\CMS\Core\Routing\PageArguments $routing */
        $routing = $this->request->getAttributes()['routing'];
        /** @var \TYPO3\CMS\Core\Site\Entity\SiteLanguage $language */
        $languageId = $this->request->getAttributes()['language']->getLanguageId();

        if($languageId === 0) {
            return $handler->handle($request);
        }

        $pid = $routing->getPageId();
        $qb = GeneralUtility::makeInstance(\TYPO3\CMS\Core\Database\ConnectionPool::class)
            ->getQueryBuilderForTable('pages');
        $translationExists = (bool) $qb->select('*')->from('pages')
            ->where(
                $qb->expr()->eq('l10n_parent', $pid),
                $qb->expr()->eq('sys_language_uid', $languageId)
            )->execute()->rowCount();

        if($translationExists === true) {
            return $handler->handle($request);
        }

        $configuration = [
            'parameter' => $pid,
            'language' => 0,
            'addQueryString' => 1,
            'forceAbsoluteUrl' => true
        ];

        $cObj = GeneralUtility::makeInstance(\TYPO3\CMS\Frontend\ContentObject\ContentObjectRenderer::class);
        $uriToDefaultPage = $cObj->typoLink_URL($configuration);

        return new \TYPO3\CMS\Core\Http\RedirectResponse($uriToDefaultPage, 302);
    }
}