public async Task Valid_Code_Request()
        {
            var client = await _clients.FindClientByIdAsync("codeclient");
            var store = new InMemoryAuthorizationCodeStore();

            var code = new AuthorizationCode
            {
                Client = client,
                RedirectUri = "https://server/cb",
                RequestedScopes = new List<Scope>
                {
                    new Scope
                    {
                        Name = "openid"
                    }
                }
            };

            await store.StoreAsync("valid", code);

            var validator = Factory.CreateTokenRequestValidator(
                authorizationCodeStore: store);

            var parameters = new NameValueCollection();
            parameters.Add(Constants.TokenRequest.GrantType, Constants.GrantTypes.AuthorizationCode);
            parameters.Add(Constants.TokenRequest.Code, "valid");
            parameters.Add(Constants.TokenRequest.RedirectUri, "https://server/cb");

            var result = await validator.ValidateRequestAsync(parameters, client);

            result.IsError.Should().BeFalse();
        }
        public async Task Unknown_Grant_Type()
        {
            var client = await _clients.FindClientByIdAsync("codeclient");
            var store = new InMemoryAuthorizationCodeStore();

            var code = new AuthorizationCode
            {
                Client = client,
                IsOpenId = true,
                RedirectUri = new Uri("https://server/cb"),
            };

            await store.StoreAsync("valid", code);

            var validator = Factory.CreateTokenValidator(
                authorizationCodeStore: store);

            var parameters = new NameValueCollection();
            parameters.Add(Constants.TokenRequest.GrantType, "unknown");
            parameters.Add(Constants.TokenRequest.Code, "valid");
            parameters.Add(Constants.TokenRequest.RedirectUri, "https://server/cb");

            var result = await validator.ValidateRequestAsync(parameters, client);

            Assert.IsTrue(result.IsError);
            Assert.AreEqual(Constants.TokenErrors.UnsupportedGrantType, result.Error);
        }
        public async Task Invalid_AuthorizationCode()
        {
            var client = await _clients.FindClientByIdAsync("codeclient");
            var store = new InMemoryAuthorizationCodeStore();

            var code = new AuthorizationCode
            {
                Client = client,
                IsOpenId = true,
                RedirectUri = "https://server/cb",
            };

            await store.StoreAsync("valid", code);

            var validator = Factory.CreateTokenRequestValidator(
                authorizationCodeStore: store);

            var parameters = new NameValueCollection();
            parameters.Add(Constants.TokenRequest.GrantType, Constants.GrantTypes.AuthorizationCode);
            parameters.Add(Constants.TokenRequest.Code, "invalid");
            parameters.Add(Constants.TokenRequest.RedirectUri, "https://server/cb");

            var result = await validator.ValidateRequestAsync(parameters, client);

            result.IsError.Should().BeTrue();
            result.Error.Should().Be(Constants.TokenErrors.InvalidGrant);
        }
        public async Task Reused_AuthorizationCode()
        {
            var client = await _clients.FindClientByIdAsync("codeclient");
            var store = new InMemoryAuthorizationCodeStore();

            var code = new AuthorizationCode
            {
                Client = client,
                IsOpenId = true,
                RedirectUri = new Uri("https://server/cb"),
            };

            await store.StoreAsync("valid", code);

            var validator = Factory.CreateTokenValidator(
                authorizationCodeStore: store,
                customRequestValidator: new DefaultCustomRequestValidator());

            var parameters = new NameValueCollection();
            parameters.Add(Constants.TokenRequest.GrantType, Constants.GrantTypes.AuthorizationCode);
            parameters.Add(Constants.TokenRequest.Code, "valid");
            parameters.Add(Constants.TokenRequest.RedirectUri, "https://server/cb");

            // request first time
            var result = await validator.ValidateRequestAsync(parameters, client);

            Assert.IsFalse(result.IsError);

            // request second time
            validator = Factory.CreateTokenValidator(
                authorizationCodeStore: store,
                customRequestValidator: new DefaultCustomRequestValidator());
            
            result = await validator.ValidateRequestAsync(parameters, client);

            Assert.IsTrue(result.IsError);
            Assert.AreEqual(Constants.TokenErrors.InvalidGrant, result.Error);
        }
        public async Task Expired_AuthorizationCode()
        {
            var client = await _clients.FindClientByIdAsync("codeclient");
            var store = new InMemoryAuthorizationCodeStore();

            var code = new AuthorizationCode
            {
                Client = client,
                IsOpenId = true,
                RedirectUri = new Uri("https://server/cb"),
                CreationTime = DateTime.UtcNow.AddSeconds(-100)
            };

            await store.StoreAsync("valid", code);

            var validator = Factory.CreateTokenValidator(
                authorizationCodeStore: store);

            var parameters = new NameValueCollection();
            parameters.Add(Constants.TokenRequest.GrantType, Constants.GrantTypes.AuthorizationCode);
            parameters.Add(Constants.TokenRequest.Code, "valid");
            parameters.Add(Constants.TokenRequest.RedirectUri, "https://server/cb");

            var result = await validator.ValidateRequestAsync(parameters, client);

            Assert.IsTrue(result.IsError);
            Assert.AreEqual(Constants.TokenErrors.InvalidGrant, result.Error);
        }
        public async Task Client_Trying_To_Request_Token_Using_Another_Clients_Code()
        {
            var client1 = await _clients.FindClientByIdAsync("codeclient");
            var client2 = await _clients.FindClientByIdAsync("codeclient_restricted");
            var store = new InMemoryAuthorizationCodeStore();

            var code = new AuthorizationCode
            {
                Client = client1,
                IsOpenId = true,
                RedirectUri = new Uri("https://server/cb"),
            };

            await store.StoreAsync("valid", code);

            var validator = Factory.CreateTokenValidator(
                authorizationCodeStore: store);

            var parameters = new NameValueCollection();
            parameters.Add(Constants.TokenRequest.GrantType, Constants.GrantTypes.AuthorizationCode);
            parameters.Add(Constants.TokenRequest.Code, "valid");
            parameters.Add(Constants.TokenRequest.RedirectUri, "https://server/cb");

            var result = await validator.ValidateRequestAsync(parameters, client2);

            Assert.IsTrue(result.IsError);
            Assert.AreEqual(Constants.TokenErrors.InvalidGrant, result.Error);
        }
        public async Task Code_Request_with_disabled_User()
        {
            var client = await _clients.FindClientByIdAsync("codeclient");
            var store = new InMemoryAuthorizationCodeStore();

            var mock = new Mock<IUserService>();
            mock.Setup(u => u.IsActiveAsync(It.IsAny<ClaimsPrincipal>())).Returns(Task.FromResult(false));

            var code = new AuthorizationCode
            {
                Client = client,
                RedirectUri = "https://server/cb",
                RequestedScopes = new List<Scope>
                {
                    new Scope
                    {
                        Name = "openid"
                    }
                }
            };

            await store.StoreAsync("valid", code);

            var validator = Factory.CreateTokenRequestValidator(
                authorizationCodeStore: store,
                userService: mock.Object);

            var parameters = new NameValueCollection();
            parameters.Add(Constants.TokenRequest.GrantType, Constants.GrantTypes.AuthorizationCode);
            parameters.Add(Constants.TokenRequest.Code, "valid");
            parameters.Add(Constants.TokenRequest.RedirectUri, "https://server/cb");

            var result = await validator.ValidateRequestAsync(parameters, client);

            result.IsError.Should().BeTrue();
        }