public function getExportFiles(ExportCommand $exportCommand)
    {
        $locales = $this->determineLocalesToImport($exportCommand);
        $domains = $this->determineDomainsToImport($exportCommand);

        $translations = $this->translationRepository->getTranslationsByLocalesAndDomains($locales, $domains);

        $translationFiles = new ArrayCollection();

        /** @var Translation $translation */
        foreach ($translations as $translation) {
            $exportFileKey = $translation->getDomain() . '.' . $translation->getLocale() . '.' . $exportCommand->getFormat();

            if (!$translationFiles->containsKey($exportFileKey)) {
                $exportFile = new ExportFile();
                $exportFile->setExtension($exportCommand->getFormat());
                $exportFile->setDomain($translation->getDomain());
                $exportFile->setLocale($translation->getLocale());
                $translationFiles->set($exportFileKey, $exportFile);
            }

            $translationFiles->get($exportFileKey)->addTranslation($translation);
        }

        return $translationFiles;
    }