namespace Mr.BrickAdventures.Progression;

/// <summary>
/// Identity of one Playthrough. Several Playthroughs exist at once and the player picks between
/// them; "slot" is the word the UI uses for the same thing.
/// </summary>
/// <remarks>
/// Deliberately has no factory that generates a value. Ids are created by an adapter and passed in,
/// so nothing in the domain depends on a source of randomness.
/// </remarks>
public readonly struct PlaythroughId : IEquatable<PlaythroughId>
{
    public Guid Value { get; }

    private PlaythroughId(Guid value) => Value = value;

    public static PlaythroughId Of(Guid value) => value == Guid.Empty
        ? throw new ArgumentException("A playthrough id cannot be the empty guid.", nameof(value))
        : new PlaythroughId(value);

    public bool Equals(PlaythroughId other) => Value.Equals(other.Value);
    public override bool Equals(object? obj) => obj is PlaythroughId other && Equals(other);
    public override int GetHashCode() => Value.GetHashCode();
    public override string ToString() => Value.ToString();
}