#nullable enable
using System;
using Cysharp.Threading.Tasks;
using ShrinkContext;
using ShrinkEventBus;

namespace ShrinkContext.EventBusAdapter
{
    /// <summary>
    /// 把生成的 ShrinkEventBus 绑定包装为可逆效应。
    /// </summary>
    public static class ShrinkEventBusEffects
    {
        /// <summary>
        /// 激活生成的 [ShrinkSubscribe] 绑定，并在 Context 回滚时统一释放。
        /// </summary>
        public static ShrinkEffectHandle EffectAttach(this ShrinkCtx ctx, object target,
            ShrinkBusKey? defaultBus = null)
        {
            if (ctx == null)
                throw new ArgumentNullException(nameof(ctx));
            if (target == null)
                throw new ArgumentNullException(nameof(target));

            var binding = EventBus.Attach(target, defaultBus);
            return ctx.EffectInverse(() =>
            {
                binding.Dispose();
                return UniTask.CompletedTask;
            });
        }
    }
}