using System;
using System.Net;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
using ivf_tl_Operate.Debug;
using Xunit;

namespace IvfTl.ControlHost.Tests
{
    /// <summary>
    /// operate 端 DebugSessionClient 纯逻辑单测:用 fake HttpMessageHandler 注入响应,
    /// 验证 acquire 解析(含培养态)/SESSION_EXPIRED 触发失效回调/release 幂等/心跳定时器。
    /// </summary>
    public class DebugSessionClientTests
    {
        private sealed class FakeHandler : HttpMessageHandler
        {
            public Func<HttpRequestMessage, (HttpStatusCode, string)> Responder;
            public int HeartbeatCount;
            protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage req, CancellationToken ct)
            {
                if (req.RequestUri.AbsolutePath.Contains("heartbeat")) Interlocked.Increment(ref HeartbeatCount);
                var (code, body) = Responder(req);
                return Task.FromResult(new HttpResponseMessage(code) { Content = new StringContent(body) });
            }
        }

        [Fact]
        public async Task Acquire_ParsesSessionIdAndCultivation()
        {
            var h = new FakeHandler { Responder = _ => (HttpStatusCode.OK, "{\"ok\":true,\"result\":\"sid123\",\"cultivating\":true,\"embryoCount\":3}") };
            var c = new DebugSessionClient("http://127.0.0.1:9/", new HttpClient(h));
            var r = await c.AcquireAsync(6);
            Assert.True(r.Ok);
            Assert.Equal("sid123", r.SessionId);
            Assert.True(r.Cultivating);
            Assert.Equal(3, r.EmbryoCount);
            await c.ReleaseAsync();
        }

        [Fact]
        public async Task Command_SessionExpired_FiresOnSessionExpired()
        {
            bool fired = false;
            var h = new FakeHandler
            {
                Responder = req => req.RequestUri.AbsolutePath.Contains("command")
                    ? (HttpStatusCode.Gone, "{\"ok\":false,\"code\":\"SESSION_EXPIRED\",\"error\":\"过期\"}")
                    : (HttpStatusCode.OK, "{\"ok\":true,\"result\":\"sid123\"}")
            };
            var c = new DebugSessionClient("http://127.0.0.1:9/", new HttpClient(h));
            c.OnSessionExpired = () => fired = true;
            await c.AcquireAsync(6);
            var r = await c.CommandAsync("ReadTemp", null);
            Assert.False(r.Ok);
            Assert.Equal("SESSION_EXPIRED", r.Code);
            Assert.True(fired);
        }

        [Fact]
        public async Task Release_IsIdempotent_NoThrowWhenCalledTwice()
        {
            var h = new FakeHandler { Responder = _ => (HttpStatusCode.OK, "{\"ok\":true,\"result\":\"sid123\"}") };
            var c = new DebugSessionClient("http://127.0.0.1:9/", new HttpClient(h));
            await c.AcquireAsync(6);
            await c.ReleaseAsync();
            await c.ReleaseAsync();   // 第二次不抛
        }

        [Fact]
        public async Task Heartbeat_TimerSendsAfterAcquire()
        {
            var h = new FakeHandler { Responder = _ => (HttpStatusCode.OK, "{\"ok\":true,\"result\":\"sid123\"}") };
            var c = new DebugSessionClient("http://127.0.0.1:9/", new HttpClient(h)) { HeartbeatIntervalMs = 50 };
            await c.AcquireAsync(6);
            await Task.Delay(180);
            await c.ReleaseAsync();
            Assert.True(h.HeartbeatCount >= 2);   // 50ms 间隔 180ms 内至少 2 次
        }
    }
}