namespace Mr.BrickAdventures.Progression;

public enum LoadOutcome
{
    Loaded,
    Absent,
    Corrupt,
}

/// <summary>
/// The result of loading something from a store: it was there, it was never there, or it was there
/// and unreadable.
/// </summary>
/// <remarks>
/// Three outcomes rather than two, deliberately. The system being replaced collapsed "no save file"
/// and "version mismatch" into a single <c>false</c> from <c>LoadGame</c>, which <c>ContinueGame</c>
/// then read as "no save" — so it started a new game and overwrote the player's file. Absent means
/// offer a new game; Corrupt means tell the player something went wrong.
/// </remarks>
public sealed record LoadResult<T>(LoadOutcome Outcome, T? Value, string? Problem)
    where T : class
{
    public static LoadResult<T> Loaded(T value) => new(LoadOutcome.Loaded, value, null);
    public static LoadResult<T> Absent() => new(LoadOutcome.Absent, null, null);
    public static LoadResult<T> Corrupt(string problem) => new(LoadOutcome.Corrupt, null, problem);
}