public function setLocaleForAuthenticatedUser(InteractiveLoginEvent $event)
    {
        $user = $event->getAuthenticationToken()->getUser();
        if ($lang = $user->getLocale()) {
            $this->session->set('_locale', $lang);
        } else {
            $request = $event->getRequest();
            if ('unset' == $request->getLocale()) {
                $this->session->set('_locale', 'en');
            }
        }
    }