public void GivenSomeValidGetUserInfo_RetrieveUserInformation_ReturnsAnAuthenticatedClient()
            {
                // Arrange.
                var mockRestClient = new Mock<IRestClient>();

                var mockRestResponseRetrieveRequestToken = new Mock<IRestResponse>();
                mockRestResponseRetrieveRequestToken.Setup(x => x.StatusCode).Returns(HttpStatusCode.OK);
                mockRestResponseRetrieveRequestToken.Setup(x => x.Content)
                                                    .Returns("oauth_token=aaa&oauth_token_secret=ccc");

                var verifyLogin = new FlickrLoginResult
                {
                    User = new FlickrLoginResult.UserInner
                    {
                        Id = "some-id",
                        Username = new FlickrLoginResult.UserInner.UsernameInner
                        {
                            _content = "some-name"
                        }
                    }
                };
                var userData = new FlickrUserDataResult
                {
                    Person = new FlickrUserDataResult.PersonInner
                    {
                        Id = "some-id",
                        Username = new FlickrUserDataResult.PersonInner.ContentInner
                        {
                            _content = "some-name"
                        },
                        Realname = new FlickrUserDataResult.PersonInner.ContentInner
                        {
                            _content = "some-name"
                        },
                    }
                };

                var verifyLoginMock = new Mock<IRestResponse<FlickrLoginResult>>();
                verifyLoginMock.Setup(x => x.Data).Returns(verifyLogin);
                verifyLoginMock.Setup(x => x.StatusCode).Returns(HttpStatusCode.OK);

                var userDataMock = new Mock<IRestResponse<FlickrUserDataResult>>();
                userDataMock.Setup(x => x.Data).Returns(userData);
                userDataMock.Setup(x => x.StatusCode).Returns(HttpStatusCode.OK);

                mockRestClient
                    .Setup(x => x.Execute(It.IsAny<IRestRequest>()))
                    .Returns(mockRestResponseRetrieveRequestToken.Object);

                mockRestClient
                    .Setup(x => x.Execute<FlickrLoginResult>(It.IsAny<IRestRequest>()))
                    .Returns(verifyLoginMock.Object);

                mockRestClient
                    .Setup(x => x.Execute<FlickrUserDataResult>(It.IsAny<IRestRequest>()))
                    .Returns(userDataMock.Object);

                var flickrProvider = new FlickrProvider("a", "b", null, new RestClientFactory(mockRestClient.Object));
                var nameValueCollection = new NameValueCollection
                {
                    {"oauth_token", "aaa"},
                    {"oauth_verifier", "bbb"}
                };

                // Act.
                var result = flickrProvider.AuthenticateClient(nameValueCollection, "asd");

                // Assert.
                Assert.NotNull(result);
                Assert.Equal("flickr", result.ProviderName);
                Assert.NotNull(result.UserInformation);
                Assert.NotNull(result.UserInformation.Id);
                Assert.NotNull(result.UserInformation.Name);
                Assert.NotNull(result.UserInformation.UserName);
            }
            public void GivenExecutingVerifyLoginThrowsAnException_AuthenticateClient_ThrowsAnAuthenticationException()
            {
                // Arrange.
                const string exceptionMessage = "some mock exception.";
                var mockRestClient = new Mock<IRestClient>();

                var mockRestResponseRetrieveRequestToken = new Mock<IRestResponse>();
                mockRestResponseRetrieveRequestToken.Setup(x => x.StatusCode).Returns(HttpStatusCode.OK);
                mockRestResponseRetrieveRequestToken.Setup(x => x.Content)
                                                    .Returns("oauth_token=aaa&oauth_token_secret=ccc");

                var verifyLogin = new FlickrLoginResult
                {
                    User = new FlickrLoginResult.UserInner
                    {
                        Id = "some-id",
                        Username =  new FlickrLoginResult.UserInner.UsernameInner
                        {
                            _content = "some-name"
                        }
                    }
                };
                var mockRestResponseVerifyCredentials = new Mock<IRestResponse<FlickrLoginResult>>();
                mockRestResponseVerifyCredentials.Setup(x => x.Data).Returns(verifyLogin);

                mockRestClient
                    .Setup(x => x.Execute(It.IsAny<IRestRequest>()))
                    .Returns(mockRestResponseRetrieveRequestToken.Object);
                mockRestClient
                    .Setup(x => x.Execute<FlickrLoginResult>(It.IsAny<IRestRequest>()))
                    .Throws(new Exception(exceptionMessage));

                var flickrProvider = new FlickrProvider("a", "b", null, new RestClientFactory(mockRestClient.Object));
                var nameValueCollection = new NameValueCollection
                {
                    {"oauth_token", "aaa"},
                    {"oauth_verifier", "bbb"}
                };
                // Act.
                var result =
                    Assert.Throws<AuthenticationException>(
                        () => flickrProvider.AuthenticateClient(nameValueCollection, "asd"));

                // Assert.
                Assert.NotNull(result);
                Assert.Equal("Failed to retrieve Login json data from the Flickr Api.", result.Message);
            }