using Avalonia;
using Avalonia.Headless;
using Avalonia.Markup.Xaml.Styling;
using AvParser.UI.HeadlessTests;
using ReactiveUI.Avalonia;
using Semi.Avalonia;

[assembly: AvaloniaTestApplication(typeof(TestAppBuilder))]
// The headless platform is one dispatcher per assembly; running collections in parallel produces
// intermittent "call from invalid thread" failures rather than useful signal.
[assembly: CollectionBehavior(DisableTestParallelization = true)]

namespace AvParser.UI.HeadlessTests;

/// <summary>Boots a headless Avalonia application for <c>[AvaloniaFact]</c> tests.</summary>
public static class TestAppBuilder
{
    /// <summary>Called by Avalonia.Headless.XUnit once per test assembly.</summary>
    public static AppBuilder BuildAvaloniaApp() =>
        AppBuilder
            .Configure<HeadlessTestApp>()
            .UseHeadless(new AvaloniaHeadlessPlatformOptions())
            .UseReactiveUI(_ => { });
}

/// <summary>
/// A minimal application that loads the real styles but never touches the DI container.
/// </summary>
/// <remarks>
/// Deliberately not <c>AvParser.Desktop.App</c>: these tests should exercise the views and the
/// stylesheet, not Serilog, the settings file or the composition root. Styles are added in code
/// rather than XAML so the test project needs no Avalonia XAML compilation of its own.
/// </remarks>
public sealed class HeadlessTestApp : Application
{
    /// <inheritdoc />
    public override void Initialize()
    {
        Styles.Add(new SemiTheme());

        var index = new Uri("avares://AvParser.UI/Styles/Index.axaml");
        Styles.Add(new StyleInclude(index) { Source = index });
    }
}