namespace OECS;

/// <summary>
/// Describes the kind of tick being processed.
/// </summary>
public enum TickType
{
    /// <summary>
    /// A timed tick, carrying a delta time (e.g., frame-based update).
    /// </summary>
    Timed,

    /// <summary>
    /// A logical tick, carrying no delta time (e.g., fixed-step simulation).
    /// </summary>
    Logical
}

/// <summary>
/// Data passed to systems during a tick.
/// </summary>
public readonly struct Tick
{
    /// <summary>
    /// The kind of tick.
    /// </summary>
    public TickType Type { get; }

    /// <summary>
    /// The elapsed time since the last tick, in seconds.
    /// Always 0 for logical ticks.
    /// </summary>
    public float DeltaTime { get; }

    private Tick(TickType type, float deltaTime)
    {
        Type = type;
        DeltaTime = deltaTime;
    }

    /// <summary>
    /// Creates a timed tick with the given delta time.
    /// </summary>
    public static Tick Timed(float deltaTime) => new(TickType.Timed, deltaTime);

    /// <summary>
    /// Creates a logical tick (no delta time).
    /// </summary>
    public static Tick Logical() => new(TickType.Logical, 0f);
}