public function postTwoFactor()
    {
        // Check that we have a session.
        if ($userId = Session::pull('2fa_id')) {
            $code = str_replace(' ', '', Binput::get('code'));

            // Maybe a temp login here.
            Auth::loginUsingId($userId);

            $user = Auth::user();

            $valid = Google2FA::verifyKey($user->google_2fa_secret, $code);

            if ($valid) {
                event(new UserPassedTwoAuthEvent($user));

                event(new UserLoggedInEvent($user));

                return Redirect::intended('dashboard');
            } else {
                event(new UserFailedTwoAuthEvent($user));

                // Failed login, log back out.
                Auth::logout();

                return cachet_redirect('auth.login')->withError(trans('forms.login.invalid-token'));
            }
        }

        return cachet_redirect('auth.login')->withError(trans('forms.login.invalid-token'));
    }