using OpenCvSharp;
using SHH.CameraSdk.HikFeatures;
using System.Runtime.ExceptionServices;
using System.Security;

namespace SHH.CameraSdk;

/// <summary>
/// [海康驱动] 工业级视频源实现 V3.4.0 (运维增强版)
/// 修复记录：
/// 1. [Fix Bug Z] 控制器遮蔽：移除子类 Controller 定义，复用基类实例，修复 FPS 控制失效问题。
/// 2. [Feat A] 热更新支持：实现 OnApplyOptions，支持码流/句柄不亦断线热切换。
/// 3. [Feat B] 审计集成：全面接入 AddAuditLog，对接 Web 运维仪表盘。
/// </summary>
public class HikVideoSource : BaseVideoSource, 
    IHikContext, ITimeSyncFeature, IRebootFeature, IPtzFeature
{
    #region --- 静态资源 (Global Resources) ---

    // 静态路由表
    private static readonly ConcurrentDictionary<int, HikVideoSource> _instances = new();
    // 全局异常回调
    private static readonly HikNativeMethods.EXCEPTION_CALLBACK _globalExceptionCallback = StaticOnSdkException;
    // 端口抢占锁
    private static readonly object _globalPortLock = new();

    #endregion

    // 声明组件
    private readonly HikTimeSyncProvider _timeProvider;
    private readonly HikRebootProvider _rebootProvider;
    private readonly HikPtzProvider _ptzProvider;

    // ==========================================
    // 实现 IHikContext (核心数据暴露)
    // ==========================================
    public int GetUserId() => _userId; // 暴露父类或私有的 _userId
    public string GetDeviceIp() => Config.IpAddress;

    // ==========================================
    // 实现 ITimeSyncFeature (路由转发)
    // ==========================================
    // 核心逻辑：全部委托给 _timeProvider 处理，自己不写一行逻辑
    public Task<DateTime> GetTimeAsync() => _timeProvider.GetTimeAsync();

    public Task SetTimeAsync(DateTime time) => _timeProvider.SetTimeAsync(time);

    public Task RebootAsync() => _rebootProvider.RebootAsync();

    public Task PtzControlAsync(PtzAction action, bool stop, int speed = 4)
        => _ptzProvider.PtzControlAsync(action, stop, speed);

    public Task PtzStepAsync(PtzAction action, int durationMs, int speed = 4)
        => _ptzProvider.PtzStepAsync(action, durationMs, speed);

    #region --- 实例成员 (Instance Members) ---

    private int _userId = -1;       // SDK 登录句柄
    private int _realPlayHandle = -1; // 预览句柄
    private int _playPort = -1;       // 播放端口

    private readonly object _initLock = new();
    private readonly object _bufferLock = new();

    private volatile int _connectionEpoch = 0;

    // 回调委托引用 (防止GC)
    private HikNativeMethods.REALDATACALLBACK? _realDataCallBack;
    private HikPlayMethods.DECCBFUN? _decCallBack;

    // 内存复用对象
    private Mat? _sharedYuvMat;
    private Mat? _sharedBgrMat; // (如有需要可复用，当前逻辑直接用FramePool)

    private FramePool? _framePool;
    private bool _isPoolReady = false;

    // 【关键修复 Bug Z】: 删除了这里原本的 "public FrameController Controller..." 
    // 直接使用 BaseVideoSource.Controller

    #endregion

    #region --- 构造函数 (Constructor) ---

    public HikVideoSource(VideoSourceConfig config) : base(config)
    {
        // 初始化组件，将 "this" 作为上下文传进去
        _timeProvider = new HikTimeSyncProvider(this);
        _rebootProvider = new HikRebootProvider(this);
        _ptzProvider = new HikPtzProvider(this);
    }

    #endregion

    #region --- 核心生命周期 (Core Lifecycle) ---

    protected override async Task OnStartAsync(CancellationToken token)
    {
        int currentEpoch = Interlocked.Increment(ref _connectionEpoch);

        await Task.Run(() =>
        {
            if (currentEpoch != _connectionEpoch) return;

            if (!HikSdkManager.Initialize())
                throw new CameraException(CameraErrorCode.SdkNotInitialized, "SDK初始化失败", DeviceBrand.HikVision);

            try
            {
                HikNativeMethods.NET_DVR_SetExceptionCallBack_V30(0, IntPtr.Zero, _globalExceptionCallback, IntPtr.Zero);

                // [审计] 记录登录动作
                AddAuditLog($"正在执行物理登录... ({_config.IpAddress})");

                var devInfo = new HikNativeMethods.NET_DEVICEINFO_V30();
                int newUserId = HikNativeMethods.NET_DVR_Login_V30(
                    _config.IpAddress, _config.Port, _config.Username, _config.Password, ref devInfo);

                if (currentEpoch != _connectionEpoch)
                {
                    if (newUserId >= 0) HikNativeMethods.NET_DVR_Logout(newUserId);
                    throw new OperationCanceledException("启动任务已过期");
                }

                _userId = newUserId;
                if (_userId < 0)
                {
                    uint err = HikNativeMethods.NET_DVR_GetLastError();
                    throw new CameraException(HikErrorMapper.Map(err), $"登录失败: {err}", DeviceBrand.HikVision, (int)err);
                }

                _instances.TryAdd(_userId, this);
                AddAuditLog($"物理登录成功 (UserID: {_userId})");

                // 开启取流
                if (!StartRealPlay())
                {
                    uint err = HikNativeMethods.NET_DVR_GetLastError();
                    throw new CameraException(HikErrorMapper.Map(err), $"预览失败: {err}", DeviceBrand.HikVision, (int)err);
                }

                AddAuditLog($"网络取流成功 (StreamType: {_config.StreamType})");
            }
            catch (Exception ex)
            {
                AddAuditLog($"启动异常: {ex.Message}");
                CleanupSync();
                throw;
            }
        }, token);
    }

    protected override async Task OnStopAsync()
    {
        Interlocked.Increment(ref _connectionEpoch);
        AddAuditLog("正在执行停止流程...");
        await Task.Run(() => CleanupSync());
        AddAuditLog("设备已停止");
    }

    private void CleanupSync()
    {
        lock (_initLock)
        {
            // 1. 停止预览
            if (_realPlayHandle >= 0)
            {
                HikNativeMethods.NET_DVR_StopRealPlay(_realPlayHandle);
                _realPlayHandle = -1;
            }

            // 2. 停止解码
            if (_playPort >= 0)
            {
                HikPlayMethods.PlayM4_Stop(_playPort);
                HikPlayMethods.PlayM4_CloseStream(_playPort);
                HikPlayMethods.PlayM4_FreePort(_playPort);
                _playPort = -1;
            }

            lock (_bufferLock)
            {
                _sharedYuvMat?.Dispose(); _sharedYuvMat = null;
                _sharedBgrMat?.Dispose(); _sharedBgrMat = null;
            }

            // 3. 注销登录
            if (_userId >= 0)
            {
                _instances.TryRemove(_userId, out _);
                HikNativeMethods.NET_DVR_Logout(_userId);
                _userId = -1;
            }

            _framePool?.Dispose();
            _framePool = null;
            _isPoolReady = false;
        }
        HikSdkManager.Uninitialize();
    }

    #endregion

    #region --- [新功能] 动态参数热应用 (Hot Swap) ---

    // 【关键修复 Feat A】实现基类的抽象方法，处理码流切换
    protected override void OnApplyOptions(DynamicStreamOptions options)
    {
        // 1. 码流热切换逻辑
        if (options.StreamType.HasValue)
        {
            int targetStream = options.StreamType.Value;
            AddAuditLog($"收到码流切换请求: {targetStream}，开始执行热切换...");

            lock (_initLock)
            {
                // A. 停止预览 (Keep Login)
                if (_realPlayHandle >= 0)
                {
                    HikNativeMethods.NET_DVR_StopRealPlay(_realPlayHandle);
                    _realPlayHandle = -1;
                }

                // B. 清理播放库 (防止旧流数据残留)
                if (_playPort >= 0)
                {
                    HikPlayMethods.PlayM4_Stop(_playPort);
                    HikPlayMethods.PlayM4_CloseStream(_playPort);
                    HikPlayMethods.PlayM4_FreePort(_playPort);
                    _playPort = -1;
                }

                // C. 更新内部配置状态
                _config.StreamType = targetStream;

                // D. 重新开启预览
                if (StartRealPlay())
                {
                    AddAuditLog($"码流热切换成功 (当前: {(_config.StreamType == 0 ? "主" : "子")}码流)");
                }
                else
                {
                    uint err = HikNativeMethods.NET_DVR_GetLastError();
                    AddAuditLog($"码流切换失败: {err}");
                }
            }
        }

        // 2. 句柄动态更新逻辑 (如有需要)
        if (options.RenderHandle.HasValue)
        {
            // 如果是硬解码模式，可以在这里调用 PlayM4_Play(port, newHandle)
            AddAuditLog($"收到新句柄绑定请求: {options.RenderHandle}");
        }
    }

    #endregion

    #region --- 网络取流 (Network Streaming) ---

    private bool StartRealPlay()
    {
        var previewInfo = new HikNativeMethods.NET_DVR_PREVIEWINFO
        {
            hPlayWnd = (IntPtr)_config.RenderHandle,
            lChannel = _config.ChannelIndex,
            dwStreamType = (uint)_config.StreamType,
            bBlocked = false
        };

        _realDataCallBack = new HikNativeMethods.REALDATACALLBACK(SafeOnRealDataReceived);
        _realPlayHandle = HikNativeMethods.NET_DVR_RealPlay_V40(_userId, ref previewInfo, _realDataCallBack, IntPtr.Zero);

        return _realPlayHandle >= 0;
    }

    private void SafeOnRealDataReceived(int lRealHandle, uint dwDataType, IntPtr pBuffer, uint dwBufSize, IntPtr pUser)
    {
        try
        {
            // 【关键位置】：在此处调用，统计网络层收到的每一字节数据
            // 因为 dwBufSize > 0，MarkFrameReceived 内部只会累加码流，不会增加 FPS 计数
            MarkFrameReceived(dwBufSize);

            if (_realPlayHandle == -1) return;

            // 处理系统头
            if (dwDataType == HikNativeMethods.NET_DVR_SYSHEAD && _playPort == -1)
            {
                lock (_initLock)
                {
                    if (_realPlayHandle == -1 || _playPort != -1) return;

                    bool getPortSuccess;
                    lock (_globalPortLock)
                    {
                        getPortSuccess = HikPlayMethods.PlayM4_GetPort(ref _playPort);
                    }

                    if (!getPortSuccess) return;

                    HikPlayMethods.PlayM4_SetDisplayBuf(_playPort, 1); // 极速模式
                    HikPlayMethods.PlayM4_SetStreamOpenMode(_playPort, 0);

                    if (!HikPlayMethods.PlayM4_OpenStream(_playPort, pBuffer, dwBufSize, 2 * 1024 * 1024))
                    {
                        HikPlayMethods.PlayM4_FreePort(_playPort);
                        _playPort = -1;
                        return;
                    }

                    _decCallBack = new HikPlayMethods.DECCBFUN(SafeOnDecodingCallBack);
                    HikPlayMethods.PlayM4_SetDecCallBackEx(_playPort, _decCallBack, IntPtr.Zero, 0);
                    HikPlayMethods.PlayM4_Play(_playPort, IntPtr.Zero);
                }
            }
            // 处理流数据
            else if (dwDataType == HikNativeMethods.NET_DVR_STREAMDATA && _playPort != -1)
            {
                HikPlayMethods.PlayM4_InputData(_playPort, pBuffer, dwBufSize);
            }
        }
        catch { }
    }

    #endregion

    #region --- 解码与帧分发 (Decoding) ---

    // 必须同时加上 SecurityCritical
    [HandleProcessCorruptedStateExceptions]
    [SecurityCritical]
    private void SafeOnDecodingCallBack(int nPort, IntPtr pBuf, int nSize, ref HikPlayMethods.FRAME_INFO pFrameInfo, int nReserved1, int nReserved2)
    {
        // [优化] 维持心跳，防止被哨兵误杀
        MarkFrameReceived(0);

        // [新增] 捕获并更新分辨率
        // 只有当分辨率发生变化时才写入，减少属性赋值开销
        if (Width != pFrameInfo.nWidth || Height != pFrameInfo.nHeight)
        {
            Width = pFrameInfo.nWidth;
            Height = pFrameInfo.nHeight;
        }

        // 1. [核心流控] 询问基类控制器：这帧要不要？
        // 之前失效是因为操作的是子类被遮蔽的 Controller，现在复用基类 Controller，逻辑就通了。
        // 传入真实的输入帧率作为参考基准
        var decision = Controller.MakeDecision(Environment.TickCount64, (int)RealFps);

        // 如果没人要，直接丢弃，不进行 Mat 转换，节省 CPU
        if (!decision.IsCaptured) return;

        int width = pFrameInfo.nWidth;
        int height = pFrameInfo.nHeight;

        // 2. 初始化帧池
        if (!_isPoolReady)
        {
            lock (_initLock)
            {
                if (!_isPoolReady)
                {
                    _framePool?.Dispose();
                    _framePool = new FramePool(width, height, MatType.CV_8UC3, initialSize: 3, maxSize: 5);
                    _isPoolReady = true;
                }
            }
        }

        if (_framePool == null) return;

        // 3. 转换与分发
        SmartFrame smartFrame = _framePool.Get();
        try
        {
            if (smartFrame == null) return; // 池满丢帧

            using (var rawYuvWrapper = Mat.FromPixelData(height + height / 2, width, MatType.CV_8UC1, pBuf))
            {
                Cv2.CvtColor(rawYuvWrapper, smartFrame.InternalMat, ColorConversionCodes.YUV2BGR_YV12);
            }

            smartFrame.SubscriberIds.AddRange(decision.TargetAppIds);

            // =========================================================================
            // 【修正】删除这里的 GlobalStreamDispatcher.Dispatch！
            // 严禁在这里分发，因为这时的图是“生的”，还没经过 Pipeline 处理。
            // =========================================================================GlobalStreamDispatcher.Dispatch(Id, smartFrame);

            // 4. [分发] 将决策结果传递给处理中心
            // decision.TargetAppIds 包含了 "谁需要这一帧" 的信息
            //GlobalProcessingCenter.Submit(this.Id, smartFrame, decision);
            GlobalPipelineRouter.Enqueue(Id, smartFrame, decision);
        }
        catch (Exception ex)
        {
            smartFrame.Dispose();
            // 这里为了性能不频繁写日志，仅在调试时开启
            // Debug.WriteLine(ex.Message);
        }
        finally
        {
            if (smartFrame != null)
                smartFrame.Dispose();
        }
    }

    #endregion

    #region --- 异常处理 ---

    private static void StaticOnSdkException(uint dwType, int lUserID, int lHandle, IntPtr pUser)
    {
        try
        {
            if (_instances.TryGetValue(lUserID, out var instance))
            {
                instance.AddAuditLog($"SDK报警异常: 0x{dwType:X}"); // 写入审计
                instance.ReportError(new CameraException(
                    CameraErrorCode.NetworkUnreachable,
                    $"SDK全局异常: 0x{dwType:X}",
                    DeviceBrand.HikVision));
            }
        }
        catch { }
    }

    #endregion

    protected override Task<DeviceMetadata> OnFetchMetadataAsync() => Task.FromResult(new DeviceMetadata());
}