public async Task<IActionResult> Register(RegisterViewModel model)
        {
            if ( ModelState.IsValid )
            {
                var user = new ApplicationUser { UserName = model.Email, Email = model.Email };
                var result = await _userManager.CreateAsync(user, model.Password);
                if ( result.Succeeded )
                {
                    // For more information on how to enable account confirmation and password reset please visit http://go.microsoft.com/fwlink/?LinkID=532713
                    // Send an email with this link
                    //var code = await _userManager.GenerateEmailConfirmationTokenAsync(user);
                    //var callbackUrl = Url.Action("ConfirmEmail", "Account", new { userId = user.Id, code = code }, protocol: HttpContext.Request.Scheme);
                    //await _emailSender.SendEmailAsync(model.Email, "Confirm your account",
                    //    "Please confirm your account by clicking this link: <a href=\"" + callbackUrl + "\">link</a>");
                    await _signInManager.SignInAsync(user, isPersistent: false);
                    _logger.LogInformation(3, "User created a new account with password.");
                    return RedirectToAction(nameof(HomeController.Index), "Home");
                }
                AddErrors(result);
            }

            // If we got this far, something failed, redisplay form
            return View(model);
        }
        public async Task<IActionResult> ExternalLoginConfirmation(ExternalLoginConfirmationViewModel model, string returnUrl = null)
        {
            if ( User.IsSignedIn() )
            {
                return RedirectToAction(nameof(ManageController.Index), "Manage");
            }

            if ( ModelState.IsValid )
            {
                // Get the information about the user from the external login provider
                var info = await _signInManager.GetExternalLoginInfoAsync();
                if ( info == null )
                {
                    return View("ExternalLoginFailure");
                }
                var user = new ApplicationUser { UserName = model.Email, Email = model.Email };
                var result = await _userManager.CreateAsync(user);
                if ( result.Succeeded )
                {
                    result = await _userManager.AddLoginAsync(user, info);
                    if ( result.Succeeded )
                    {
                        await _signInManager.SignInAsync(user, isPersistent: false);
                        _logger.LogInformation(6, "User created an account using {Name} provider.", info.LoginProvider);
                        return RedirectToLocal(returnUrl);
                    }
                }
                AddErrors(result);
            }

            ViewData["ReturnUrl"] = returnUrl;
            return View(model);
        }