using Microsoft.Extensions.Hosting;
using OpenCvSharp;
using SHH.Contracts;
using SHH.NetMQ;

namespace SHH.CameraSdk
{
    public class ZeroMqBridgeService : BackgroundService
    {
        private readonly DistributorServer _distributor;
        private readonly ForwarderClient _forwarder;

        public ZeroMqBridgeService(DistributorServer distributor, ForwarderClient forwarder)
        {
            _distributor = distributor;
            _forwarder = forwarder;
        }

        protected override Task ExecuteAsync(CancellationToken stoppingToken)
        {
            Console.WriteLine("[Bridge] 正在连接全局广播总线...");

            // 【关键修改】直接订阅静态的全局事件
            // 不需要传入 APP_ID，因为这是 C# 原生事件，不是字典查找
            GlobalStreamDispatcher.OnGlobalFrame += BridgeHandler;

            Console.WriteLine("[Bridge] 全局总线连接成功！任何动态增删的设备都会自动转发。");
            return Task.CompletedTask;
        }

        // 真正的事件处理函数
        private void BridgeHandler(long deviceId, SmartFrame frame)
        {
            try
            {
                // 1. 安全检查
                var sourceMat = frame.TargetMat ?? frame.InternalMat;
                if (sourceMat == null || sourceMat.Empty()) return;

                // 2. 内存克隆 (Deep Copy) - 这一步不能省
                using var safeMat = sourceMat.Clone();

                // 3. 编码 & 封装
                // 建议：可以在这里判断一下 deviceId，如果某些设备不想发，可以在这里 return
                var jpgParams = new int[] { (int)ImwriteFlags.JpegQuality, 70 };
                byte[] jpgBytes = safeMat.ImEncode(".jpg", jpgParams);

                var payload = new VideoPayload
                {
                    CameraId = deviceId.ToString(),
                    CaptureTime = DateTime.Now,
                    DispatchTime = DateTime.Now,
                    OriginalWidth = safeMat.Width,
                    OriginalHeight = safeMat.Height,
                    OriginalImageBytes = jpgBytes
                };

                // 4. 发射
                _distributor.Broadcast(payload);
                _forwarder.Push(payload);
            }
            catch (Exception ex)
            {
                // Console.WriteLine(ex.Message); // 生产环境建议注释掉，防止日志刷屏
            }
        }

        public override Task StopAsync(CancellationToken cancellationToken)
        {
            // 优雅退订，防止内存泄漏
            GlobalStreamDispatcher.OnGlobalFrame -= BridgeHandler;
            return base.StopAsync(cancellationToken);
        }
    }
}