public enum TriggerExpiration {
    Never,
    StartOfNextHeroTurn,
}

public enum TriggerRepetition {
    Once,
    Multiple,
}

public class Trigger {

    private TriggeredEffect callback;
    private TriggerExpiration expiration;
    private TriggerRepetition repetition;
    private bool expired;

    public Trigger(TriggeredEffect callback, TriggerExpiration expiration,
            TriggerRepetition repetition) {
        this.callback = callback;
        this.expiration = expiration;
        this.repetition = repetition;
    }

    public void Run(IBattleEffectApplier effectApplier) {
        if (this.expired) return;
        callback(effectApplier);
        if (this.repetition == TriggerRepetition.Once) {
            this.expired = true;
        }
    }

    public bool Expired {get => this.expired;}
    public TriggerExpiration Expiration {get => this.expiration;}
    public TriggerRepetition Repetition {get => this.repetition;}
}