MainWindow.axaml

<Window xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        x:Class="Avalonia.Controls.WebView.Samples.Oidc.MainWindow"
        Title="OAuth 2.0 Authorization Server Metadata (RFC 8414) + PKCE"
        Width="720"
        Height="640">
    <DockPanel Margin="12">
        <StackPanel DockPanel.Dock="Top" Spacing="8">
            <TextBlock TextWrapping="Wrap"
                       Text="Uses /.well-known/oauth-authorization-server, then authorization code with PKCE (S256). Register the redirect URI with your identity provider." />
            <TextBlock Text="Issuer (authorization server identifier URL)" FontWeight="SemiBold" />
            <TextBox x:Name="IssuerBox"
                     Text="https://login.microsoftonline.com/common/v2.0" />
            <TextBlock Text="Client ID" FontWeight="SemiBold" />
            <TextBox x:Name="ClientIdBox"
                     PlaceholderText="Application (client) ID" />
            <TextBlock Text="Redirect URI (must match app registration)" FontWeight="SemiBold" />
            <TextBox x:Name="RedirectBox"
                     Text="http://localhost" />
            <TextBlock Text="Scope" FontWeight="SemiBold" />
            <TextBox x:Name="ScopeBox"
                     Text="openid profile offline_access" />
            <Button HorizontalAlignment="Left"
                    Content="Sign in (metadata → broker → token)"
                    Click="SignIn_OnClick" />
        </StackPanel>
        <TextBlock DockPanel.Dock="Top"
                   Margin="0,12,0,4"
                   Text="Log"
                   FontWeight="SemiBold" />
        <ScrollViewer>
            <TextBox x:Name="LogBox"
                     AcceptsReturn="True"
                     IsReadOnly="True"
                     TextWrapping="Wrap"
                     FontFamily="Consolas" />
        </ScrollViewer>
    </DockPanel>
</Window>