namespace Mr.BrickAdventures.Progression.Tests;

/// <summary>
/// The test-side adapter for <see cref="IPlaythroughStore"/>. Its existence alongside the JSON store
/// is what makes the port a real seam rather than a hypothetical one.
/// </summary>
internal sealed class InMemoryPlaythroughStore : IPlaythroughStore
{
    private readonly Dictionary<Guid, PlaythroughSnapshot> _saved = new();
    private readonly HashSet<Guid> _corrupt = new();

    public void Save(Playthrough playthrough) => _saved[playthrough.Id.Value] = playthrough.Export();

    /// <summary>Simulates a file that exists but cannot be read back into a valid snapshot.</summary>
    public void Corrupt(PlaythroughId id) => _corrupt.Add(id.Value);

    public LoadResult<Playthrough> Load(PlaythroughId id)
    {
        if (_corrupt.Contains(id.Value))
            return LoadResult<Playthrough>.Corrupt("snapshot could not be read");

        if (!_saved.TryGetValue(id.Value, out var snapshot))
            return LoadResult<Playthrough>.Absent();

        try
        {
            return LoadResult<Playthrough>.Loaded(Playthrough.Restore(snapshot));
        }
        catch (Exception e)
        {
            return LoadResult<Playthrough>.Corrupt(e.Message);
        }
    }
}