using Avalonia.Media.Imaging;
using AvParser.Core.Collecting;
using AvParser.UI.Media;

namespace AvParser.UI.HeadlessTests;

/// <summary>
/// A cache that decodes nothing.
/// </summary>
/// <remarks>
/// Returning null is exactly what the real cache does for a video or a missing blob, so the view
/// models are already required to cope with it — which is what makes this an honest stand-in
/// rather than a convenient one. It records what was asked for, so tests can assert that a page
/// requested previews at all.
/// </remarks>
internal sealed class FakeThumbnailCache : IThumbnailCache
{
    public List<(string Sha256, int Width)> Requested { get; } = [];

    public Task<Bitmap?> GetAsync(
        string sha256,
        string extension,
        MediaKind kind,
        int width,
        CancellationToken ct = default
    )
    {
        lock (Requested)
        {
            Requested.Add((sha256, width));
        }

        return Task.FromResult<Bitmap?>(null);
    }

    public void Clear() => Requested.Clear();
}