#nullable enable
using System.Collections.Generic;
using Cysharp.Threading.Tasks;
using NUnit.Framework;
using ShrinkContext;
using ShrinkEventBus;
using UnityEngine;

namespace ShrinkContext.EventBusAdapter.Tests
{
    public sealed class PingEvent : IShrinkEvent
    {
        public int Value { get; set; }
    }

    /// <summary>
    /// EventBus 订阅/注册即效应：组件停用时自动退订，无需手写卸载路径。
    /// </summary>
    public class EventBusEffectTests
    {
        private ShrinkContextRuntime _runtime = null!;
        private ShrinkCtx _ctx = null!;

        [SetUp]
        public void SetUp()
        {
            _runtime = new ShrinkContextRuntime();
            _ctx = _runtime.RootContext;
        }

        [TearDown]
        public void TearDown()
        {
            _runtime.ShutdownAsync().GetAwaiter().GetResult();
        }

        [Test]
        public void EffectAttach_ReceivesEvents_AndAutoUnsubscribesOnContextDispose()
        {
            var received = new List<int>();
            var subscriber = new InstanceSubscriber(received);
            _ctx.EffectAttach(subscriber);

            EventBus.Post(new PingEvent { Value = 1 });
            EventBus.Post(new PingEvent { Value = 2 });
            CollectionAssert.AreEqual(new[] { 1, 2 }, received);

            _ctx.DisposeAsync().GetAwaiter().GetResult();

            EventBus.Post(new PingEvent { Value = 3 });
            CollectionAssert.AreEqual(new[] { 1, 2 }, received,
                "上下文回滚后 EventBus binding 必须通过 IDisposable.Dispose 自动退订");
        }

        [Test]
        public void EffectAttach_ManualDispose_OnlyUnsubscribesOwn()
        {
            var first = new List<int>();
            var second = new List<int>();
            _ctx.EffectAttach(new InstanceSubscriber(first));
            var handle = _ctx.EffectAttach(new InstanceSubscriber(second));

            handle.DisposeAsync().GetAwaiter().GetResult();

            EventBus.Post(new PingEvent { Value = 7 });
            CollectionAssert.AreEqual(new[] { 7 }, first, "手动退订只影响自己的订阅");
            Assert.IsEmpty(second);
        }

        [Test]
        public void EffectAttach_ObjectSubscribers_AutoUnregisterOnContextDispose()
        {
            var values = new List<int>();
            var subscriber = new InstanceSubscriber(values);
            _ctx.EffectAttach(subscriber);

            EventBus.Post(new PingEvent { Value = 5 });
            Assert.AreEqual(5, subscriber.LastValue);

            _ctx.DisposeAsync().GetAwaiter().GetResult();

            EventBus.Post(new PingEvent { Value = 6 });
            Assert.AreEqual(5, subscriber.LastValue, "实例注册随上下文回滚自动注销");
        }

        [ShrinkEventSubscriber(DefaultBus = "game")]
        private sealed class InstanceSubscriber
        {
            private readonly List<int> _values;

            public InstanceSubscriber(List<int> values)
            {
                _values = values;
            }

            public int LastValue { get; private set; }

            [ShrinkSubscribe]
            public void OnPing(PingEvent e)
            {
                LastValue = e.Value;
                _values.Add(e.Value);
            }
        }
    }
}