using System.Collections.Concurrent;
using Microsoft.Extensions.Hosting;
using NetMQ;
using NetMQ.Sockets;
using MessagePack;
using SHH.CameraSdk;
using SHH.Contracts;
using System.Text;

namespace SHH.CameraService
{
    public class DeviceStateMonitorWorker : BackgroundService
    {
        private readonly CameraManager _manager;
        private readonly ServiceConfig _config;
        private readonly InterceptorPipeline _pipeline;

        // 修改点1: 改为 Socket 列表
        private readonly List<DealerSocket> _sockets = new();
        private readonly ConcurrentDictionary<string, StatusEventPayload> _stateStore = new();

        private volatile bool _isDirty = false;
        private long _lastSendTick = 0;

        public DeviceStateMonitorWorker(
            CameraManager manager,
            ServiceConfig config,
            InterceptorPipeline pipeline)
        {
            _manager = manager;
            _config = config;
            _pipeline = pipeline;
        }

        protected override async Task ExecuteAsync(CancellationToken stoppingToken)
        {
            // 1. 初始化
            foreach (var dev in _manager.GetAllDevices())
            {
                UpdateLocalState(dev.Id, false, "Init");
            }

            _manager.OnDeviceStatusChanged += OnSdkStatusChanged;

            // 修改点2: 遍历所有端点建立连接
            if (_config.CommandEndpoints.Count == 0) return;

            Console.WriteLine($"[StatusWorker] 启动状态上报，目标节点数: {_config.CommandEndpoints.Count}");

            foreach (var ep in _config.CommandEndpoints)
            {
                try
                {
                    var socket = new DealerSocket();
                    // 状态通道也建议设置 Identity，方便服务端追踪
                    socket.Options.Identity = Encoding.UTF8.GetBytes(_config.AppId + "_status");
                    socket.Options.SendHighWatermark = 1000;
                    socket.Connect(ep.Uri);
                    _sockets.Add(socket);
                }
                catch (Exception ex)
                {
                    Console.WriteLine($"[StatusWorker] 连接失败 {ep.Uri}: {ex.Message}");
                }
            }

            // 定时循环 (1秒1次)
            var timer = new PeriodicTimer(TimeSpan.FromSeconds(1));
            try
            {
                while (await timer.WaitForNextTickAsync(stoppingToken))
                {
                    await CheckAndBroadcastAsync();
                }
            }
            finally
            {
                _manager.OnDeviceStatusChanged -= OnSdkStatusChanged;
                // 清理所有 socket
                foreach (var s in _sockets) s.Dispose();
            }
        }

        private void OnSdkStatusChanged(long deviceId, bool isOnline, string reason)
        {
            UpdateLocalState(deviceId, isOnline, reason);
            _isDirty = true;
        }

        private void UpdateLocalState(long deviceId, bool isOnline, string reason)
        {
            var evt = new StatusEventPayload
            {
                CameraId = deviceId.ToString(),
                IsOnline = isOnline,
                Reason = reason,
                Timestamp = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()
            };
            _stateStore[deviceId.ToString()] = evt;
        }

        // 修改点3: 广播发送逻辑
        private async Task CheckAndBroadcastAsync()
        {
            long now = Environment.TickCount64;
            // 策略: 有变更 或 超过5秒(心跳)
            bool shouldSend = _isDirty || (now - _lastSendTick > 5000);

            if (shouldSend && _sockets.Count > 0)
            {
                try
                {
                    var snapshot = _stateStore.Values.ToList();
                    var batch = new StatusBatchPayload
                    {
                        Items = snapshot,
                        Timestamp = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()
                    };

                    byte[] data = MessagePackSerializer.Serialize(batch);

                    // 拦截器处理
                    var ctx = await _pipeline.ExecuteSendAsync("STATUS_BATCH", data);
                    if (ctx != null)
                    {
                        // ★★★ 核心修复：循环广播给所有 Socket ★★★
                        foreach (var socket in _sockets)
                        {
                            // TrySend 避免阻塞，如果某个服务端卡死不影响其他端
                            socket.SendMoreFrame(ctx.Protocol).TrySendFrame(ctx.Data);
                        }

                        _isDirty = false;
                        _lastSendTick = now;
                    }
                }
                catch (Exception ex)
                {
                    Console.WriteLine($"[StatusWorker] 发送失败: {ex.Message}");
                }
            }
        }
    }
}