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

namespace ShrinkNetwork.Integration.App.Tests
{
    /// <summary>
    /// 阶段 3 验收（EditMode 部分）：Network 组件热插拔——
    /// 停用时传输解绑、会话清理、服务键撤回、依赖者停用，全部为效应回滚结果。
    /// </summary>
    public class ShrinkNetworkAppComponentTests
    {
        private ShrinkContextRuntime _runtime = null!;

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

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

        private static void Run(UniTask task) => task.GetAwaiter().GetResult();

        [Test]
        public void Apply_ProvidesServiceKey_AndBindsLoopbackWithSession()
        {
            var sessionsBefore = ShrinkNetworkRuntime.Default.Sessions.Count;
            var fiber = _runtime.Use(new ShrinkNetworkAppComponent(),
                new ShrinkNetworkAppModuleConfig { BindLoopbackTransport = true, LoopbackSessionId = 7 });

            Assert.AreEqual(ShrinkFiberState.Active, fiber.State);
            Assert.IsTrue(_runtime.TryGetRaw<ShrinkNetworkService>(_runtime.RootContext,
                ShrinkNetworkAppComponent.ServiceKey, out var service));
            Assert.AreSame(ShrinkNetworkRuntime.Default, service);
            Assert.AreEqual(sessionsBefore + 1, service.Sessions.Count, "loopback 绑定应新建一个会话");
        }

        [Test]
        public void Retire_UnbindsTransport_ClearsSessions_AndStopsDependents()
        {
            var sessionsBefore = ShrinkNetworkRuntime.Default.Sessions.Count;
            var consumerFiber = _runtime.Use(new ServiceConsumerComponent());
            Assert.AreEqual(ShrinkFiberState.Inactive, consumerFiber.State, "网络服务未提供前依赖者等待");

            var networkFiber = _runtime.Use(new ShrinkNetworkAppComponent(),
                new ShrinkNetworkAppModuleConfig { BindLoopbackTransport = true });
            Assert.AreEqual(ShrinkFiberState.Active, networkFiber.State);
            Assert.AreEqual(ShrinkFiberState.Active, consumerFiber.State, "服务键发布后依赖者激活");

            Run(_runtime.RetireAsync(networkFiber));

            Assert.AreEqual(sessionsBefore, ShrinkNetworkRuntime.Default.Sessions.Count,
                "停用必须解绑传输并清理自己的会话（效应回滚，非手写卸载；不影响他人遗留会话）");
            Assert.IsFalse(_runtime.TryGetRaw<ShrinkNetworkService>(_runtime.RootContext,
                ShrinkNetworkAppComponent.ServiceKey, out _), "服务键随 set 的逆操作撤回");
            Assert.AreEqual(ShrinkFiberState.Inactive, consumerFiber.State, "依赖者随提供者停用");
        }

        [Test]
        public void Reactivate_RebindsLoopback()
        {
            var sessionsBefore = ShrinkNetworkRuntime.Default.Sessions.Count;
            var first = _runtime.Use(new ShrinkNetworkAppComponent(),
                new ShrinkNetworkAppModuleConfig { BindLoopbackTransport = true });
            Run(_runtime.RetireAsync(first));
            Assert.AreEqual(sessionsBefore, ShrinkNetworkRuntime.Default.Sessions.Count);

            var second = _runtime.Use(new ShrinkNetworkAppComponent(),
                new ShrinkNetworkAppModuleConfig { BindLoopbackTransport = true });
            Assert.AreEqual(ShrinkFiberState.Active, second.State);
            Assert.AreEqual(sessionsBefore + 1, ShrinkNetworkRuntime.Default.Sessions.Count, "重新激活重新绑定传输");
        }

        /// <summary>注入网络服务键的消费者组件。</summary>
        private sealed class ServiceConsumerComponent : IShrinkComponent
        {
            public string Name => "network-consumer";
            public IReadOnlyList<string> Inject { get; } = new[] { ShrinkNetworkAppComponent.ServiceKey };
            public IReadOnlyList<string> Provide => Array.Empty<string>();
            public ShrinkNetworkService? Seen { get; private set; }

            public UniTask ApplyAsync(ShrinkCtx ctx, object? config)
            {
                Seen = ctx.Get<ShrinkNetworkService>(ShrinkNetworkAppComponent.ServiceKey);
                return UniTask.CompletedTask;
            }
        }
    }
}