private void InputButton_Click(object sender, RoutedEventArgs e)
        {
            if (PasswordBox.Password != String.Empty && LoginBox.Text != String.Empty)
            {
                /*if (SaveLoginBox.IsChecked.Value)
                    SaveLogin();
                else
                    DeleteLogin();*/

                // discover endpoints from metadata
                var client = new HttpClient();

                var disco = client.GetDiscoveryDocumentAsync("http://localhost:5000");
                if (disco.IsFaulted)
                {
                    MessageBox.Show("something wrong");
                    return;
                }

                // request token
                var tokenResponse = client.RequestPasswordTokenAsync(new PasswordTokenRequest
                {
                    Address = "http://localhost:5000/connect/token",
                    ClientId = "ro.client",
                    ClientSecret = "secret",

                    UserName = "alice",
                    Password = "Pass123$",
                    Scope = "api1"

                });

                if (tokenResponse.IsFaulted)
                {
                    MessageBox.Show("something wrong2");
                    return;
                }

                MessageBox.Show(tokenResponse.ToString());

                AuthorizationGrid.Visibility = Visibility.Collapsed;
                MainGrid.Visibility = Visibility.Visible;
                SetDefault();
            }
        }