protected function getDatabaseClass($databaseClasses)
    {
        $envDatabase = Environment::getEnv('SS_DATABASE_CLASS');
        if ($envDatabase) {
            return $envDatabase;
        }

        // Check supported versions
        foreach ($this->preferredDatabases as $candidate) {
            if (!empty($databaseClasses[$candidate]['supported'])) {
                return $candidate;
            }
        }
        return null;
    }