public async Task<ActionResult> ExternalLoginConfirmation(ExternalLoginConfirmationViewModel model,
            string returnUrl, string userName)
        {
            model.UserName = userName;
            if (User.Identity.IsAuthenticated)
            {
                return RedirectToAction("Index", "Manage");
            }

            if (ModelState.IsValid)
            {
                // Get the information about the user from the external login provider
                var info = await AuthenticationManager.GetExternalLoginInfoAsync();
                if (info == null)
                {
                    return View("ExternalLoginFailure");
                }
                var user = new Attendee {UserName = model.UserName, Email = model.Email};
                var result = await UserManager.CreateAsync(user);
                if (result.Succeeded)
                {
                    result = await UserManager.AddLoginAsync(user.Id, info.Login);
                    if (result.Succeeded)
                    {
                        await SignInManager.SignInAsync(user, false, false);
                        return RedirectToLocal(returnUrl);
                    }
                }
                AddErrors(result);
            }

            ViewBag.ReturnUrl = returnUrl;
            return View(model);
        }
        public async Task<ActionResult> Register(RegisterViewModel model)
        {
            if (ModelState.IsValid)
            {
                var user = new Attendee {UserName = model.UserName, Email = model.Email};
                var result = await UserManager.CreateAsync(user, model.Password);
                if (result.Succeeded)
                {
                    var callbackUrl = await SendEmailConfirmationTokenAsync(user.Id, "Account confirmation");
                    ViewBag.errorMessage = "Please confirm the email was sent to you.";
                    return View("DisplayEmail");
                }
                AddErrors(result);
            }

            // If we got this far, something failed, redisplay form
            return View(model);
        }