public async Task <ActionResult> Start(LoginBindingModel model, string returnUrl)
        {
            if (!ModelState.IsValid)
            {
                return(RedirectToAction("Index", model));
            }

            var uri   = Request.IsLocal ? Constant.LOCAL_TOKEN_URI : Constant.REMOTE_TOKEN_URI;
            var token = await RequestHelpers.GetTokenAsync(model.Email, model.Password, uri);

            if (token != null)
            {
                return(Redirect(returnUrl));
            }

            return(RedirectToAction("Index", model));
        }