private function determineRouterScript($router, $env, SymfonyStyle $io)
    {
        /*
        if (null === $router) {
            $router = $this
                ->getContainer()
                ->get('kernel')
                ->locateResource(sprintf('@FrameworkBundle/Resources/config/router_%s.php', $env))
            ;
        }
        */

        if (false === $path = realpath($router)) {
            $io->error(sprintf('The given router script "%s" does not exist.', $router));

            return false;
        }

        return $path;
    }