public async Task<ActionResult> Index()
        {
            if (!Request.IsAuthenticated)
            {
                var temporaryEmail = "temporary-user@" + Guid.NewGuid() + ".com";
                var user = new ApplicationUser
                {
                    UserName = temporaryEmail,
                    Email = temporaryEmail,
                    IsTemporary = true
                };

                var result = await _userService.CreateTemporaryAsync(user);

                if (result.Succeeded)
                {
                    await _authenticationService.SignInAsync(user, false, false);
                    ViewData["IsTemporaryUser"] = true;
                }
                else
                {
                    //handle cart storage. use session?
                }
            }
            else
            {
                string userId = _userService.GetUserId();
                ViewData["IsTemporaryUser"] = _userService.IsTemporary(userId);
            }

            //loads the partial            
            return View();
        }
        public async Task<ActionResult> Register(RegisterViewModel model)
        {
            if (ModelState.IsValid)
            {
                string oldUserId = _userService.GetUserId();
                var wasAnonymous = _userService.IsTemporary(oldUserId);

                if (!wasAnonymous)
                {
                    return new HttpStatusCodeResult(HttpStatusCode.Forbidden, "loggedIn");
                }

                _authenticationService.SignOut(DefaultAuthenticationTypes.ApplicationCookie);                

                var user = new ApplicationUser { UserName = model.Email, Email = model.Email };
                var result = await _userService.CreateAsync(user, model.Password);
                if (result.Succeeded)
                {                   
                    await _authenticationService.SignInAsync(user, isPersistent: false, rememberBrowser: false);

                    // For more information on how to enable account confirmation and password reset please visit http://go.microsoft.com/fwlink/?LinkID=320771
                    // Send an email with this link
                    // string code = await UserManager.GenerateEmailConfirmationTokenAsync(user.Id);
                    // var callbackUrl = Url.Action("ConfirmEmail", "Account", new { userId = user.Id, code = code }, protocol: Request.Url.Scheme);
                    // await UserManager.SendEmailAsync(user.Id, "Confirm your account", "Please confirm your account by clicking <a href=\"" + callbackUrl + "\">here</a>");

                    try
                    {
                        if (!_cartService.HasEmptyCart(oldUserId))
                        {                            
                            _cartService.Transfer(oldUserId, user.Id);
                        }
                    }                    
                    catch (Exception)
                    {
                        return new HttpStatusCodeResult(HttpStatusCode.InternalServerError);
                    }

                    return new HttpStatusCodeResult(HttpStatusCode.OK);
                }
                AddErrors(result);
            }

            // If we got this far, something failed, redisplay form
            Response.StatusCode = (int)HttpStatusCode.BadRequest;
            return Json(model, JsonRequestBehavior.DenyGet);
        }
        public async Task<ActionResult> LogOut()
        {
            _authenticationService.SignOut(DefaultAuthenticationTypes.ApplicationCookie);

            var temporaryEmail = "temporary-user@" + Guid.NewGuid() + ".com";
            var user = new ApplicationUser
            {
                UserName = temporaryEmail,
                Email = temporaryEmail,
                IsTemporary = true
            };

            //create a temporary user again
            var result = await _userService.CreateTemporaryAsync(user);

            if (result.Succeeded)
            {
                await _authenticationService.SignInAsync(user, false, false);
                ViewData["IsTemporaryUser"] = true;
            }            

            return new HttpStatusCodeResult(HttpStatusCode.OK);
        }    
 public async Task SignInAsync(ApplicationUser user, bool isPersistent, bool rememberBrowser)
 {
     await SignInManager.SignInAsync(user, isPersistent, rememberBrowser);
 }