using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net.Sockets;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using TeamAAS_VP.Core.RFID;

namespace TeamAAS_VP.Core.PLCs
{
    /// <summary>
    /// 三菱 PLC MC 协议客户端（3E 帧 / 二进制 / TCP）
    /// 适用于 Q/L/iQ-R/FX5 等系列以太网通讯
    /// </summary>
    public class MitsubishiPLC : IDisposable
    {
        // 3E 帧副头部 + 访问路径固定 9 字节，其后才是「数据长度」字段指定的内容
        private const int McHeaderLength = 9;

        private TcpClient _client;
        private NetworkStream _stream;
        private readonly object _sync = new object();

        public string IpAddress { get; }
        public int Port { get; }
        public byte NetworkNo { get; set; } = 0x00;
        public byte PcNo { get; set; } = 0xFF;
        public ushort IoModuleNo { get; set; } = 0x03FF;
        public byte StationNo { get; set; } = 0x00;
        public int TimeoutMs { get; set; } = 3000;

        public event Action<string> OnLog;
        public event Action ConnectionLost;

        public bool IsConnected => _client != null && _client.Connected;

        public MitsubishiPLC(string ipAddress, int port = 5000)
        {
            IpAddress = ipAddress;
            Port = port;
        }

        public bool Connect()
        {
            try
            {
                Disconnect();

                _client = new TcpClient();
                _client.NoDelay = true;
                _client.ReceiveTimeout = TimeoutMs;
                _client.SendTimeout = TimeoutMs;
                _client.Connect(IpAddress, Port);
                _stream = _client.GetStream();
                _stream.ReadTimeout = TimeoutMs;
                _stream.WriteTimeout = TimeoutMs;

                OnLog?.Invoke("已连接三菱 PLC (" + IpAddress + ":" + Port + ")");
                return true;
            }
            catch (Exception ex)
            {
                OnLog?.Invoke("连接 PLC 失败: " + ex.Message);
                Disconnect();
                return false;
            }
        }

        public void Disconnect()
        {
            try
            {
                if (_stream != null)
                    _stream.Close();
                if (_client != null)
                    _client.Close();
            }
            catch
            {
                // ignore cleanup errors
            }
            finally
            {
                _stream = null;
                _client = null;
            }
        }

        /// <summary>
        /// 读 Ready 位（PLC→PC 请求读卡）。未配置则抛异常。
        /// </summary>
        public bool ReadReadyBit(PlcRfidMapping mapping)
        {
            if (mapping == null)
                throw new ArgumentNullException(nameof(mapping));
            if (!IsDeviceEnabled(mapping.ReadyBitDevice))
                throw new InvalidOperationException("Ready 位未配置（不能为 0）");

            lock (_sync)
                return ReadBit(mapping.ReadyBitDevice);
        }

        /// <summary>
        /// 读 PLC 指定的读写头端口号。
        /// </summary>
        public int ReadRequestPort(PlcRfidMapping mapping)
        {
            if (mapping == null)
                throw new ArgumentNullException(nameof(mapping));
            if (!IsDeviceEnabled(mapping.PortDevice))
                throw new InvalidOperationException("端口寄存器未配置（不能为 0）");

            lock (_sync)
            {
                short[] words = ReadWords(mapping.PortDevice, 1);
                return words[0];
            }
        }

        /// <summary>
        /// 读卡成功：写数据到起始地址，置 OK=1、NG=0。
        /// </summary>
        public void WriteReadSuccess(PlcRfidMapping mapping, RFIDTagData tag)
        {
            if (mapping == null)
                throw new ArgumentNullException(nameof(mapping));
            if (tag == null || tag.Data == null || tag.Data.Length == 0)
                throw new ArgumentException("标签数据无效");
            if (tag.Data.Length > mapping.MaxDataBytes)
                throw new ArgumentException("RFID 数据长度 " + tag.Data.Length + " 超过上限 " + mapping.MaxDataBytes);
            if (!IsDeviceEnabled(mapping.DataStartDevice))
                throw new ArgumentException("数据起始寄存器未配置");

            lock (_sync)
            {
                if (IsDeviceEnabled(mapping.QualityDevice))
                    WriteDevice(mapping.QualityDevice, tag.Quality);

                short[] words = BytesToWords(tag.Data);
                WriteDeviceBlock(mapping.DataStartDevice, words);

                if (IsDeviceEnabled(mapping.OkBitDevice))
                    WriteBit(mapping.OkBitDevice, true);
                if (IsDeviceEnabled(mapping.NgBitDevice))
                    WriteBit(mapping.NgBitDevice, false);

                WriteReceiveBit(mapping, true);

                OnLog?.Invoke("读卡 OK → 已写数据 端口=" + tag.Port
                    + " 字节=" + tag.Data.Length
                    + " 起始=" + mapping.DataStartDevice
                    + (IsDeviceEnabled(mapping.ReceiveBitDevice) ? " Receive=1" : ""));
            }
        }

        /// <summary>
        /// 读卡失败：置 OK=0、NG=1。
        /// </summary>
        public void WriteReadFailure(PlcRfidMapping mapping)
        {
            if (mapping == null)
                throw new ArgumentNullException(nameof(mapping));

            lock (_sync)
            {
                if (IsDeviceEnabled(mapping.OkBitDevice))
                    WriteBit(mapping.OkBitDevice, false);
                if (IsDeviceEnabled(mapping.NgBitDevice))
                    WriteBit(mapping.NgBitDevice, true);

                WriteReceiveBit(mapping, true);

                OnLog?.Invoke("读卡 NG"
                    + (IsDeviceEnabled(mapping.ReceiveBitDevice) ? " Receive=1" : ""));
            }
        }

        /// <summary>
        /// 置 Receive=1，通知 PLC 本次读卡交互已完成。
        /// </summary>
        public void WriteReceiveBit(PlcRfidMapping mapping, bool value)
        {
            if (mapping == null)
                throw new ArgumentNullException(nameof(mapping));
            if (!IsDeviceEnabled(mapping.ReceiveBitDevice))
                return;

            lock (_sync)
                WriteBit(mapping.ReceiveBitDevice, value);
        }

        /// <summary>
        /// Ready 关闭后仅清除 Receive（OK/NG 保持供 PLC 读取）。
        /// </summary>
        public void ClearReceiveBit(PlcRfidMapping mapping)
        {
            if (mapping == null)
                throw new ArgumentNullException(nameof(mapping));

            lock (_sync)
            {
                if (IsDeviceEnabled(mapping.ReceiveBitDevice))
                    WriteBit(mapping.ReceiveBitDevice, false);
            }
        }

        /// <summary>
        /// SFIS 过站/上传完成：写 OK/NG + Receive=1（OK/NG 不清除，仅清 Receive）。
        /// </summary>
        public void WriteSfisResult(PlcSfisFeedback feedback, bool isPassStation, bool success)
        {
            if (feedback == null)
                throw new ArgumentNullException(nameof(feedback));

            string okDev = isPassStation ? feedback.PassOkBitDevice : feedback.UploadOkBitDevice;
            string ngDev = isPassStation ? feedback.PassNgBitDevice : feedback.UploadNgBitDevice;
            string recvDev = isPassStation ? feedback.PassReceiveBitDevice : feedback.UploadReceiveBitDevice;
            string label = isPassStation ? "过站" : "上传";

            lock (_sync)
            {
                if (IsDeviceEnabled(okDev))
                    WriteBit(okDev, success);
                if (IsDeviceEnabled(ngDev))
                    WriteBit(ngDev, !success);
                if (IsDeviceEnabled(recvDev))
                    WriteBit(recvDev, true);

                OnLog?.Invoke(label + (success ? " OK" : " NG")
                    + (IsDeviceEnabled(recvDev) ? " Receive=1" : string.Empty));
            }
        }

        /// <summary>SFIS 信号关闭后仅清除对应 Receive。</summary>
        public void ClearSfisReceiveBit(PlcSfisFeedback feedback, bool isPassStation)
        {
            if (feedback == null)
                throw new ArgumentNullException(nameof(feedback));

            string recvDev = isPassStation ? feedback.PassReceiveBitDevice : feedback.UploadReceiveBitDevice;
            if (!IsDeviceEnabled(recvDev))
                return;

            lock (_sync)
                WriteBit(recvDev, false);
        }

        private bool _heartbeatBitOn;
        private short _heartbeatWord;

        /// <summary>连接后重置心跳内部计数/翻转状态。</summary>
        public void ResetHeartbeatState()
        {
            lock (_sync)
            {
                _heartbeatBitOn = false;
                _heartbeatWord = 0;
            }
        }

        /// <summary>
        /// 根据地址类型发送一次心跳：M 等位元件翻转 bool，D 等字元件递增数值。
        /// </summary>
        public void PulseHeartbeat(string device)
        {
            if (!IsDeviceEnabled(device))
                return;

            PlcHeartbeatKind kind = ResolveHeartbeatKind(device);
            lock (_sync)
            {
                if (kind == PlcHeartbeatKind.Bit)
                {
                    _heartbeatBitOn = !_heartbeatBitOn;
                    WriteBit(device, _heartbeatBitOn);
                }
                else
                {
                    _heartbeatWord++;
                    if (_heartbeatWord <= 0)
                        _heartbeatWord = 1;
                    WriteDevice(device, _heartbeatWord);
                }
            }
        }

        /// <summary>解析心跳模式；地址填 0 返回 Disabled。</summary>
        public static PlcHeartbeatKind ResolveHeartbeatKind(string device)
        {
            if (!IsDeviceEnabled(device))
                return PlcHeartbeatKind.Disabled;

            string type = GetDeviceTypePrefix(device);
            if (IsBitDeviceType(type))
                return PlcHeartbeatKind.Bit;
            if (IsWordDeviceType(type))
                return PlcHeartbeatKind.Word;

            throw new ArgumentException("心跳地址类型不支持（请使用 M 位或 D 字）: " + device, nameof(device));
        }

        public static string GetDeviceTypePrefix(string device)
        {
            if (string.IsNullOrWhiteSpace(device))
                throw new ArgumentException("软元件名称不能为空", nameof(device));

            var match = Regex.Match(device.Trim(), @"^([A-Za-z]+)(\d+)$");
            if (!match.Success)
                throw new ArgumentException("无法解析软元件地址: " + device, nameof(device));

            return match.Groups[1].Value.ToUpperInvariant();
        }

        private static bool IsBitDeviceType(string type)
        {
            switch (type)
            {
                case "M":
                case "L":
                case "F":
                case "V":
                case "S":
                case "X":
                case "Y":
                case "B":
                case "SM":
                    return true;
                default:
                    return false;
            }
        }

        private static bool IsWordDeviceType(string type)
        {
            switch (type)
            {
                case "D":
                case "W":
                case "SD":
                case "R":
                case "ZR":
                    return true;
                default:
                    return false;
            }
        }

        /// <summary>
        /// 软元件是否启用：空、空白或 "0" 表示不使用。
        /// </summary>
        public static bool IsDeviceEnabled(string device)
        {
            if (string.IsNullOrWhiteSpace(device))
                return false;
            return device.Trim() != "0";
        }

        /// <summary>
        /// 连接后自检：写/读一个字，确认 MC 帧交互正常。
        /// </summary>
        public bool TestCommunication(string device = "D110", short testValue = 0x55AA)
        {
            if (!IsDeviceEnabled(device))
            {
                OnLog?.Invoke("PLC 通讯测试跳过：测试地址未配置");
                return false;
            }

            lock (_sync)
            {
                try
                {
                    short[] before = null;
                    try
                    {
                        before = ReadWords(device, 1);
                    }
                    catch
                    {
                        before = null;
                    }

                    WriteDevice(device, testValue);
                    short[] after = ReadWords(device, 1);
                    bool ok = after != null && after.Length > 0 && after[0] == testValue;

                    if (before != null && before.Length > 0)
                    {
                        try { WriteDevice(device, before[0]); }
                        catch { /* ignore */ }
                    }

                    OnLog?.Invoke(ok
                        ? "PLC 通讯测试成功 (" + device + ")"
                        : "PLC 通讯测试失败: 写入 " + testValue + " 读回 "
                          + (after != null && after.Length > 0 ? after[0].ToString() : "空"));
                    return ok;
                }
                catch (Exception ex)
                {
                    OnLog?.Invoke("PLC 通讯测试异常: " + ex.Message);
                    return false;
                }
            }
        }

        /// <summary>
        /// 连接后自检：对位软元件执行 读→写反→读→恢复，并输出 MC 报文与字读交叉验证。
        /// </summary>
        public bool TestBitCommunication(string device)
        {
            if (!IsDeviceEnabled(device))
            {
                OnLog?.Invoke("PLC 位通讯测试跳过：地址未配置");
                return false;
            }

            lock (_sync)
            {
                try
                {
                    DeviceAddress addr = ParseDevice(device);
                    OnLog?.Invoke("位测试 [" + device + "] 解析地址=" + addr.Address
                        + " 软元件=0x" + addr.Code.ToString("X2"));

                    byte rawOriginal = ReadBitRaw(addr);
                    bool original = IsMcBitOn(rawOriginal);
                    WordBitSnapshot snapOriginal = ReadWordBitSnapshot(addr);
                    OnLog?.Invoke("  步骤1 位读: 0x" + rawOriginal.ToString("X2")
                        + " => " + original + " | 字读 M" + snapOriginal.WordStart
                        + " bit" + snapOriginal.BitIndex + "=" + snapOriginal.BitOn
                        + " (字=0x" + snapOriginal.WordHex + ")");

                    bool target = !original;
                    byte[] writeReq = BuildRequestBody(
                        command: 0x1401,
                        subCommand: 0x0001,
                        deviceCode: addr.Code,
                        address: addr.Address,
                        points: 1,
                        writeData: new[] { ToMcBitValue(target) });
                    OnLog?.Invoke("  步骤2 位写 " + target + " 完整帧: "
                        + FormatHex(BuildFrame(writeReq)));

                    WriteBits(addr.Code, addr.Address, new[] { target });

                    byte rawFlipped = ReadBitRaw(addr);
                    bool flipped = IsMcBitOn(rawFlipped);
                    WordBitSnapshot snapFlipped = ReadWordBitSnapshot(addr);
                    OnLog?.Invoke("  步骤3 位读: 0x" + rawFlipped.ToString("X2")
                        + " => " + flipped + " | 字读 M" + snapFlipped.WordStart
                        + " bit" + snapFlipped.BitIndex + "=" + snapFlipped.BitOn
                        + " (字=0x" + snapFlipped.WordHex + ")");

                    WriteBits(addr.Code, addr.Address, new[] { original });

                    byte rawRestored = ReadBitRaw(addr);
                    bool restored = IsMcBitOn(rawRestored);
                    OnLog?.Invoke("  步骤4 恢复写 " + original + " 位读: 0x"
                        + rawRestored.ToString("X2") + " => " + restored);

                    bool ok = flipped != original && restored == original;
                    if (!ok)
                        OnLog?.Invoke("  诊断: " + DiagnoseBitTestFailure(
                            original, rawOriginal, target, rawFlipped, snapFlipped, restored, rawRestored));

                    OnLog?.Invoke(ok
                        ? "PLC 位通讯测试成功 (" + device + ")"
                        : "PLC 位通讯测试失败 (" + device + ")");
                    return ok;
                }
                catch (Exception ex)
                {
                    OnLog?.Invoke("PLC 位通讯测试异常 (" + device + "): " + ex.Message);
                    return false;
                }
            }
        }

        private struct WordBitSnapshot
        {
            public int WordStart;
            public int BitIndex;
            public bool BitOn;
            public string WordHex;
        }

        private WordBitSnapshot ReadWordBitSnapshot(DeviceAddress addr)
        {
            int wordStart = (addr.Address / 16) * 16;
            int bitIndex = addr.Address % 16;
            short[] words = ReadWords(addr.Code, wordStart, 1);
            int word = words[0] & 0xFFFF;
            return new WordBitSnapshot
            {
                WordStart = wordStart,
                BitIndex = bitIndex,
                BitOn = (word & (1 << bitIndex)) != 0,
                WordHex = word.ToString("X4")
            };
        }

        private static string DiagnoseBitTestFailure(
            bool original, byte rawOriginal,
            bool target, byte rawFlipped, WordBitSnapshot snapFlipped,
            bool restored, byte rawRestored)
        {
            if (target && (rawFlipped == 0x10 || rawFlipped == 0x01) && snapFlipped.BitOn)
                return "位读写实际成功，请检查测试判定逻辑";
            if (target && rawOriginal == 0x00 && rawFlipped == 0x00 && !snapFlipped.BitOn)
                return "位写后位读/字读均为 OFF — 可能原因: (1) PLC 梯形图强制清 M101 "
                    + "(2) 位写报文未被 PLC 接受 (3) 未允许 RUN 中写入；请用 Hsl 对同一地址 Write/Read 对照";
            if (target && !snapFlipped.BitOn && (rawFlipped == 0x10 || rawFlipped == 0x01))
                return "位读为 ON 但字读为 OFF — 位/字地址映射或读路径异常";
            if (target && snapFlipped.BitOn && rawFlipped == 0x00)
                return "字读为 ON 但位读为 OFF — 位读响应解析可能有问题";
            if (restored != original)
                return "恢复失败，PLC 可能在持续改写该位";
            return "未知，请对照步骤2完整帧与 HslCommunication 抓包";
        }

        private static string FormatHex(byte[] data)
        {
            return BitConverter.ToString(data).Replace("-", " ");
        }

        public short[] ReadWords(string device, int count)
        {
            DeviceAddress addr = ParseDevice(device);
            return ReadWords(addr.Code, addr.Address, count);
        }

        public void WriteWords(string device, short[] values)
        {
            DeviceAddress addr = ParseDevice(device);
            WriteWords(addr.Code, addr.Address, values);
        }

        public void WriteDevice(string device, short value)
        {
            WriteWords(device, new[] { value });
        }

        public void WriteDeviceBlock(string startDevice, short[] values)
        {
            WriteWords(startDevice, values);
        }

        /// <summary>从字软元件读取指定字节数（低字节在前）。</summary>
        public byte[] ReadDeviceBytes(string device, int byteCount)
        {
            if (byteCount <= 0)
                return new byte[0];

            int wordCount = (byteCount + 1) / 2;
            short[] words = ReadWords(device, wordCount);
            byte[] all = WordsToBytes(words);
            if (all.Length <= byteCount)
                return all;

            var trimmed = new byte[byteCount];
            Array.Copy(all, trimmed, byteCount);
            return trimmed;
        }

        public void WriteBit(string device, bool value)
        {
            if (!IsDeviceEnabled(device))
                return;

            DeviceAddress addr = ParseDevice(device);
            WriteBits(addr.Code, addr.Address, new[] { value });
        }

        public bool ReadBit(string device)
        {
            if (!IsDeviceEnabled(device))
                throw new ArgumentException("位地址未启用: " + device);

            DeviceAddress addr = ParseDevice(device);
            return ReadBits(addr.Code, addr.Address, 1)[0];
        }

        public bool[] ReadBits(byte deviceCode, int address, int count)
        {
            if (count <= 0)
                throw new ArgumentOutOfRangeException(nameof(count));

            byte[] requestData = BuildRequestBody(
                command: 0x0401,
                subCommand: 0x0001,
                deviceCode: deviceCode,
                address: address,
                points: count);

            byte[] response = SendRequest(requestData);
            if (response.Length < 2 + count)
                throw new InvalidOperationException("PLC 位读响应数据长度不足");

            var result = new bool[count];
            for (int i = 0; i < count; i++)
                result[i] = IsMcBitOn(response[2 + i]);
            return result;
        }

        /// <summary>MC 协议位读响应：00H=OFF；01H 或 10H 均表示 ON。</summary>
        private static bool IsMcBitOn(byte value)
        {
            return value == 0x01 || value == 0x10;
        }

        /// <summary>MC 协议位写请求（1401/0001）：00H=OFF，10H=ON。</summary>
        private static byte ToMcBitValue(bool value)
        {
            return value ? (byte)0x10 : (byte)0x00;
        }

        private byte ReadBitRaw(DeviceAddress addr)
        {
            byte[] requestData = BuildRequestBody(
                command: 0x0401,
                subCommand: 0x0001,
                deviceCode: addr.Code,
                address: addr.Address,
                points: 1);

            byte[] response = SendRequest(requestData);
            if (response.Length < 3)
                throw new InvalidOperationException("PLC 位读响应数据长度不足");
            return response[2];
        }

        public short[] ReadWords(byte deviceCode, int address, int count)
        {
            if (count <= 0)
                throw new ArgumentOutOfRangeException(nameof(count));

            byte[] requestData = BuildRequestBody(
                command: 0x0401,
                subCommand: 0x0000,
                deviceCode: deviceCode,
                address: address,
                points: count);

            byte[] response = SendRequest(requestData);
            return ParseWordReadResponse(response, count);
        }

        public void WriteWords(byte deviceCode, int address, short[] values)
        {
            if (values == null || values.Length == 0)
                throw new ArgumentException("写入数据不能为空", nameof(values));

            byte[] requestData = BuildRequestBody(
                command: 0x1401,
                subCommand: 0x0000,
                deviceCode: deviceCode,
                address: address,
                points: values.Length,
                writeData: WordsToBytes(values));

            SendRequest(requestData);
        }

        public void WriteBits(byte deviceCode, int address, bool[] values)
        {
            if (values == null || values.Length == 0)
                throw new ArgumentException("写入数据不能为空", nameof(values));

            // 二进制位写入：每点 1 字节，00H=OFF / 10H=ON
            var data = new byte[values.Length];
            for (int i = 0; i < values.Length; i++)
                data[i] = ToMcBitValue(values[i]);

            byte[] requestData = BuildRequestBody(
                command: 0x1401,
                subCommand: 0x0001,
                deviceCode: deviceCode,
                address: address,
                points: values.Length,
                writeData: data);

            SendRequest(requestData);
        }

        /// <summary>
        /// 请求数据：监视定时器 + 指令 + 子指令 + 起始软元件(3) + 软元件代码(1) + 点数 + [写数据]
        /// 注意：二进制 3E 帧中「地址在前、软元件代码在后」。
        /// </summary>
        private static byte[] BuildRequestBody(ushort command, ushort subCommand, byte deviceCode, int address, int points, byte[] writeData = null)
        {
            using (var ms = new MemoryStream())
            using (var writer = new BinaryWriter(ms))
            {
                writer.Write((ushort)0x0010); // 监视定时器：0x10 * 250ms = 4s
                writer.Write(command);
                writer.Write(subCommand);

                // 起始软元件编号：3 字节，低字节在前
                writer.Write((byte)(address & 0xFF));
                writer.Write((byte)((address >> 8) & 0xFF));
                writer.Write((byte)((address >> 16) & 0xFF));

                // 软元件代码
                writer.Write(deviceCode);

                writer.Write((ushort)points);

                if (writeData != null && writeData.Length > 0)
                    writer.Write(writeData);

                return ms.ToArray();
            }
        }

        private byte[] BuildFrame(byte[] requestData)
        {
            using (var ms = new MemoryStream())
            using (var writer = new BinaryWriter(ms))
            {
                writer.Write((ushort)0x0050); // 请求副头部
                writer.Write(NetworkNo);
                writer.Write(PcNo);
                writer.Write(IoModuleNo); // 小端 0x03FF -> FF 03
                writer.Write(StationNo);
                writer.Write((ushort)requestData.Length);
                writer.Write(requestData);
                return ms.ToArray();
            }
        }

        private byte[] SendRequest(byte[] requestData)
        {
            if (!IsConnected || _stream == null)
                throw new InvalidOperationException("PLC 未连接");

            try
            {
                lock (_sync)
                {
                    byte[] frame = BuildFrame(requestData);
                    _stream.Write(frame, 0, frame.Length);
                    _stream.Flush();

                    // 响应头固定 9 字节（不是 11！多读会吃掉结束码，导致后续读超时）
                    byte[] header = ReadExact(McHeaderLength);
                    if (header[0] != 0xD0 || header[1] != 0x00)
                    {
                        throw new InvalidOperationException(
                            "PLC 响应副头部无效: " + BitConverter.ToString(header));
                    }

                    int dataLength = header[7] | (header[8] << 8);
                    if (dataLength < 2)
                        throw new InvalidOperationException("PLC 响应数据长度无效: " + dataLength);

                    byte[] body = ReadExact(dataLength);

                    ushort endCode = (ushort)(body[0] | (body[1] << 8));
                    if (endCode != 0)
                        throw new InvalidOperationException("PLC 返回错误码: 0x" + endCode.ToString("X4")
                            + " (" + DescribeEndCode(endCode) + ")");

                    return body;
                }
            }
            catch (Exception ex) when (IsTransportFailure(ex))
            {
                OnLog?.Invoke("PLC 通讯中断: " + ex.Message);
                NotifyConnectionLost();
                throw;
            }
        }

        private void NotifyConnectionLost()
        {
            if (_client == null)
                return;

            Disconnect();
            ConnectionLost?.Invoke();
        }

        private static bool IsTransportFailure(Exception ex)
        {
            if (ex is IOException || ex is SocketException || ex is ObjectDisposedException)
                return true;

            if (ex is InvalidOperationException && ex.Message.Contains("连接已断开"))
                return true;

            return ex.InnerException != null && IsTransportFailure(ex.InnerException);
        }

        private static string DescribeEndCode(ushort endCode)
        {
            switch (endCode)
            {
                case 0xC050: return "不允许在 RUN 中写入，请在 PLC 以太网参数中勾选允许 RUN 中写入";
                case 0xC051: return "请求数据长度错误";
                case 0xC056: return "指令/子指令不支持";
                case 0xC059: return "指令格式错误（请检查软元件代码/地址顺序）";
                case 0xC05C: return "请求内容错误";
                case 0xC061: return "请求数据长度与实际不符";
                default: return "详见三菱 MC 协议手册结束代码";
            }
        }

        private short[] ParseWordReadResponse(byte[] body, int count)
        {
            if (body.Length < 2 + count * 2)
                throw new InvalidOperationException("PLC 读响应数据长度不足");

            var result = new short[count];
            int offset = 2;
            for (int i = 0; i < count; i++)
            {
                result[i] = (short)(body[offset] | (body[offset + 1] << 8));
                offset += 2;
            }
            return result;
        }

        private byte[] ReadExact(int length)
        {
            var buffer = new byte[length];
            int read = 0;
            while (read < length)
            {
                int n = _stream.Read(buffer, read, length - read);
                if (n <= 0)
                    throw new IOException("PLC 连接已断开");
                read += n;
            }
            return buffer;
        }

        private static short[] BytesToWords(byte[] data)
        {
            int wordCount = (data.Length + 1) / 2;
            var words = new short[wordCount];
            for (int i = 0; i < wordCount; i++)
            {
                int idx = i * 2;
                byte low = data[idx];
                byte high = idx + 1 < data.Length ? data[idx + 1] : (byte)0;
                words[i] = (short)(low | (high << 8));
            }
            return words;
        }

        private static byte[] WordsToBytes(short[] words)
        {
            var data = new byte[words.Length * 2];
            for (int i = 0; i < words.Length; i++)
            {
                data[i * 2] = (byte)(words[i] & 0xFF);
                data[i * 2 + 1] = (byte)((words[i] >> 8) & 0xFF);
            }
            return data;
        }

        private struct DeviceAddress
        {
            public byte Code;
            public int Address;
        }

        private static bool TryParseDevice(string device, out DeviceAddress result)
        {
            result = default(DeviceAddress);
            try
            {
                result = ParseDevice(device);
                return true;
            }
            catch
            {
                return false;
            }
        }

        private static DeviceAddress ParseDevice(string device)
        {
            if (string.IsNullOrWhiteSpace(device))
                throw new ArgumentException("软元件名称不能为空", nameof(device));

            var match = Regex.Match(device.Trim(), @"^([A-Za-z]+)(\d+)$");
            if (!match.Success)
                throw new ArgumentException("无法解析软元件地址: " + device, nameof(device));

            string type = match.Groups[1].Value.ToUpperInvariant();
            string number = match.Groups[2].Value;

            // M/L/F/V/S/SM/SD/D/R/ZR：十进制；X/Y：GX Works 八进制；B/W/SB/SW：十六进制
            int address;
            if (type == "X" || type == "Y")
                address = Convert.ToInt32(number, 8);
            else if (type == "B" || type == "W" || type == "SB" || type == "SW")
                address = Convert.ToInt32(number, 16);
            else
                address = int.Parse(number);

            byte code;
            if (!DeviceCodes.TryGetValue(type, out code))
                throw new ArgumentException("不支持的软元件类型: " + type, nameof(device));

            return new DeviceAddress { Code = code, Address = address };
        }

        private static readonly Dictionary<string, byte> DeviceCodes = new Dictionary<string, byte>(StringComparer.OrdinalIgnoreCase)
        {
            { "SM", 0x91 },
            { "SD", 0xA9 },
            { "M", 0x90 },
            { "L", 0x92 },
            { "F", 0x93 },
            { "V", 0x94 },
            { "S", 0x98 },
            { "X", 0x9C },
            { "Y", 0x9D },
            { "B", 0xA0 },
            { "D", 0xA8 },
            { "W", 0xB4 },
            { "R", 0xAF },
            { "ZR", 0xB0 }
        };

        public void Dispose()
        {
            Disconnect();
            GC.SuppressFinalize(this);
        }
    }

    public enum PlcHeartbeatKind
    {
        Disabled,
        Bit,
        Word
    }

    /// <summary>
    /// RFID 与 PLC 握手寄存器映射。
    /// 流程：PLC 置 Ready → PC 读端口号并读卡 → 写数据 → 写 OK/NG → 写 Receive
    /// → 等 Ready 关闭 → PC 仅清 Receive。
    /// 地址填 "0" 表示不使用该软元件。
    /// </summary>
    public class PlcRfidMapping
    {
        /// <summary>RFID 原始数据起始寄存器（PC 写入）</summary>
        public string DataStartDevice { get; set; } = "D110";

        /// <summary>端口号寄存器（PLC 写入，PC 读取）</summary>
        public string PortDevice { get; set; } = "D101";

        /// <summary>数据质量（PC 写入，可选）</summary>
        public string QualityDevice { get; set; } = "D102";

        /// <summary>Ready 位（PLC→PC 请求读卡）</summary>
        public string ReadyBitDevice { get; set; } = "M100";

        /// <summary>读 OK 位（PC→PLC）</summary>
        public string OkBitDevice { get; set; } = "0";

        /// <summary>读 NG 位（PC→PLC）</summary>
        public string NgBitDevice { get; set; } = "0";

        /// <summary>Receive 位（PC→PLC，读卡完成后置 1）</summary>
        public string ReceiveBitDevice { get; set; } = "0";

        /// <summary>最大转发字节数</summary>
        public int MaxDataBytes { get; set; } = 32;

        /// <summary>单次读卡超时（毫秒）</summary>
        public int ReadTimeoutMs { get; set; } = 2000;
    }

    /// <summary>
    /// SFIS 过站/上传 PLC 回写映射（PC→PLC）。
    /// 流程：信号上升沿触发 SFIS → 写 OK/NG + Receive → 信号关闭后仅清 Receive。
    /// </summary>
    public class PlcSfisFeedback
    {
        public string PassOkBitDevice { get; set; } = "M106";
        public string PassNgBitDevice { get; set; } = "M107";
        public string PassReceiveBitDevice { get; set; } = "M108";
        public string UploadOkBitDevice { get; set; } = "M109";
        public string UploadNgBitDevice { get; set; } = "M110";
        public string UploadReceiveBitDevice { get; set; } = "M111";
    }
}