protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, System.Threading.CancellationToken cancellationToken)
        {
            var context = request.GetRequestContext();
            var user = context.Principal.Identity;

            if (!user.IsAuthenticated)
            {
                IdentityResult result;
                ApplicationUserManager userManager = request.GetOwinContext().GetUserManager<ApplicationUserManager>();

                var appUser = await userManager.FindByNameAsync(DummyName);
                if (appUser == null)
                {
                    appUser = new ApplicationUser() { UserName = DummyName, Email = DummyName };

                    result = await userManager.CreateAsync(appUser);

                }
                ClaimsIdentity oAuthIdentity = await appUser.GenerateUserIdentityAsync(userManager, OAuthDefaults.AuthenticationType);

                context.Principal = new ClaimsPrincipal(oAuthIdentity);
            }

            return await base.SendAsync(request, cancellationToken);
        }
        public async Task<IHttpActionResult> RegisterExternal(RegisterExternalBindingModel model)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            var info = await Authentication.GetExternalLoginInfoAsync();
            if (info == null)
            {
                return InternalServerError();
            }

            var user = new ApplicationUser() { UserName = model.Email, Email = model.Email };

            IdentityResult result = await UserManager.CreateAsync(user);
            if (!result.Succeeded)
            {
                return GetErrorResult(result);
            }

            result = await UserManager.AddLoginAsync(user.Id, info.Login);
            if (!result.Succeeded)
            {
                return GetErrorResult(result); 
            }
            return Ok();
        }
        public async Task<IHttpActionResult> Register(RegisterBindingModel model)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            var user = new ApplicationUser() { UserName = model.Email, Email = model.Email };

            IdentityResult result = await UserManager.CreateAsync(user, model.Password);

            if (!result.Succeeded)
            {
                return GetErrorResult(result);
            }

            return Ok();
        }