public async Task<ActionResult> Login(LoginModel model)
        {
            if (!ModelState.IsValid)
            {
                return View(model);
            }

            var blogContext = new BlogContext();
            // XXX WORK HERE
            // fetch a user by the email in model.Email

            User user = await blogContext.Users.Find(Builders<User>.Filter.Eq(x => x.Email, model.Email)).SingleOrDefaultAsync();

            if (user == null)
            {
                ModelState.AddModelError("Email", "Email address has not been registered.");
                return View(model);
            }

            var identity = new ClaimsIdentity(new[]
                {
                    new Claim(ClaimTypes.Name, user.Name),
                    new Claim(ClaimTypes.Email, user.Email)
                },
                "ApplicationCookie");

            var context = Request.GetOwinContext();
            var authManager = context.Authentication;

            authManager.SignIn(identity);

            return Redirect(GetRedirectUrl(model.ReturnUrl));
        }
        public ActionResult Login(string returnUrl)
        {
            var model = new LoginModel
            {
                ReturnUrl = returnUrl
            };

            return View(model);
        }
        public async Task<ActionResult> Login(LoginModel model)
        {
            if (!ModelState.IsValid)
            {
                return View(model);
            }

            var blogContext = new BlogContext();
            // XXX WORK HERE
            // fetch a user by the email in model.Email

            string email = model.Email;
            var builder = Builders<User>.Filter;
            FilterDefinition<User> searchFilter = builder.Eq("Email", email);
            IMongoCollection<User> usersCollection =  getCollection();

            User user = null;
            var list = await usersCollection.Find(searchFilter).Limit(1).ToListAsync();
            foreach (User doc in list)
            {
                Console.WriteLine("Found User:"******"Email", "Email address has not been registered.");
                return View(model);
            }

            var identity = new ClaimsIdentity(new[]
                {
                    new Claim(ClaimTypes.Name, user.Name),
                    new Claim(ClaimTypes.Email, user.Email)
                },
                "ApplicationCookie");

            var context = Request.GetOwinContext();
            var authManager = context.Authentication;

            authManager.SignIn(identity);

            return Redirect(GetRedirectUrl(model.ReturnUrl));
        }