namespace Recordingtest.Bridge;

/// <summary>
/// Generic, SUT-neutral abstraction for reading the current engine state of
/// a WPF application under test. Implementations may delegate to a SUT-side
/// in-process bridge (HmEG-aware tier), to a reflection probe, or to a stub.
///
/// This interface lives in <c>Recordingtest.Bridge.Abstractions</c> so that
/// every higher tier (HmEG-aware / app-specific) can target it without the
/// generic core ever seeing a SUT-specific symbol.
/// </summary>
public interface IEngineStateProvider
{
    IReadOnlyList<string> GetSelectedIds();
    CameraSnapshot GetCamera();
    SceneSnapshot GetScene();
    bool GetRenderComplete();
    /// <summary>
    /// Restore the camera state in the live SUT. Best-effort: implementations
    /// that cannot write the camera (reflection fallback, null provider) must
    /// swallow any exception and return silently.
    /// </summary>
    void SetCamera(CameraSnapshot snapshot);
}

public sealed record CameraSnapshot(double[] Eye, double[] Target, double[] Up, double Fov);
public sealed record SceneSnapshot(int ObjectCount, string? DocumentPath);

/// <summary>
/// Safe-default provider used when no real SUT bridge is available
/// (CI / unit tests / startup race window).
/// </summary>
public sealed class NullEngineStateProvider : IEngineStateProvider
{
    public IReadOnlyList<string> GetSelectedIds() => Array.Empty<string>();
    public CameraSnapshot GetCamera() => new(
        new double[] { 0, 0, 0 },
        new double[] { 0, 0, 0 },
        new double[] { 0, 0, 1 },
        45.0);
    public SceneSnapshot GetScene() => new(0, null);
    public bool GetRenderComplete() => true;
    public void SetCamera(CameraSnapshot snapshot) { /* no-op */ }
}