eaxing_back_africa_main/Service/Plc/Codec/Decoder.cs

using DotNetty.Buffers;
using DotNetty.Codecs;
using DotNetty.Transport.Channels;
using HybirdFrameworkCore.Utils;
using HybirdFrameworkDriver.Session;
using log4net;
using Newtonsoft.Json;
using Service.Charger.Client;
using Service.Charger.Msg;
using Service.Charger.Msg.Charger.Req;
using Service.Charger.Msg.Charger.Resp;

namespace Service.Charger.Codec;

/// <summary>
/// 解码器
/// </summary>
public class Decoder : ByteToMessageDecoder
{
    private readonly IByteBuffer[] _delimiters = { Unpooled.CopiedBuffer(PlcConst.StartChar) };

    /// <summary>
    ///
    /// </summary>
    /// <param name="chargerSn"></param>
    /// <returns></returns>
    private ILog Log(string? chargerSn)
    {
        if (ObjUtils.IsNotNullOrWhiteSpace(chargerSn))
        {
            return LogManager.GetLogger("Plc" + chargerSn);
        }

        return LogManager.GetLogger(typeof(Decoder));
    }


    #region MyRegion

    #endregion

    protected override void Decode(IChannelHandlerContext context, IByteBuffer buffer, List<object> output)
    {
        string? chargerSn = ChannelUtils.GetAttr(context.Channel, PlcConst.ChargerSn);
        IByteBuffer? delimiter = FindDelimiter(buffer);
        if (delimiter != null)
        {
            //分隔符索引
            int delimiterIndex = IndexOf(buffer, delimiter);
            //帧长索引
            int frameLengthIndex = delimiterIndex + delimiter.Capacity;

            if (delimiterIndex > 0)
            {
                buffer.SkipBytes(delimiterIndex);
                return;
            }

            if (buffer.ReadableBytes < frameLengthIndex + 2)
            {
                // 数据不足，等待更多数据
                return;
            }

            // 读取长度字段
            int frameLength = buffer.GetUnsignedShortLE(buffer.ReaderIndex + frameLengthIndex);
            //总帧长
            int totalFrameLength = delimiterIndex + delimiter.Capacity + 2 + frameLength;
            // int totalFrameLength = delimiterIndex + frameLength;
            // 最小总帧长过滤
            if (totalFrameLength < 21)
            {
                return;
            }

            if (buffer.ReadableBytes < totalFrameLength)
            {
                // 数据不足，等待更多数据
                return;
            }

            byte[]? data = null;
            try
            {
                ASDU asdu = Parse(buffer, totalFrameLength, delimiter, out data);
                Log(chargerSn).Info($"receive {BitUtls.BytesToHexStr(data)}:{JsonConvert.SerializeObject(asdu)} from {chargerSn}");
                output.Add(asdu);
            }
            catch (Exception e)
            {
                Log(chargerSn).Error($"decode fail msg={BitUtls.BytesToHexStr(data)}");
            }
        }
    }

    private IByteBuffer? FindDelimiter(IByteBuffer buffer)
    {
        foreach (IByteBuffer delimiter in _delimiters)
        {
            int delimiterIndex = IndexOf(buffer, delimiter);
            if (delimiterIndex >= 0)
            {
                return delimiter;
            }
        }

        return null;
    }

    private static int IndexOf(IByteBuffer haystack, IByteBuffer needle)
    {
        for (int i = haystack.ReaderIndex; i < haystack.WriterIndex; i++)
        {
            int num = i;
            int j;
            for (j = 0; j < needle.Capacity && haystack.GetByte(num) == needle.GetByte(j); j++)
            {
                num++;
                if (num == haystack.WriterIndex && j != needle.Capacity - 1)
                {
                    return -1;
                }
            }

            if (j == needle.Capacity)
            {
                return i - haystack.ReaderIndex;
            }
        }

        return -1;
    }

    public ASDU Parse(IByteBuffer byteBuffer, int totalFrameLength, IByteBuffer delimiter, out byte[] data)
    {
        data = new byte[totalFrameLength];
        byteBuffer.ReadBytes(data);

        int removeIndex = delimiter.Capacity;

        ushort cmd = data[14 + removeIndex];
        byte[] bytes = new byte[data.Length - (23 + removeIndex)];
        Array.Copy(data, 23 + removeIndex, bytes, 0, bytes.Length);


        ASDU baseMsg = cmd switch
        {
            /*0x*/
            93 => ModelConvert.Decode<StartBatterySwapResq>(bytes),
            /*0x*/
            82 => ModelConvert.Decode<WarehousCompleteReq>(bytes),
            /*0x*/
            76 => ModelConvert.Decode<BatteryStatusReportedReq>(bytes),
            /*0x*/
            106 => ModelConvert.Decode<VehicleModelResq>(bytes),
            /*0x*/
            200 => ModelConvert.Decode<SummaryFailuresReq>(bytes),
            /*0x*/
            83 => ModelConvert.Decode<MigrationCompleteReq>(bytes),
            /*0x*/
            78 => ModelConvert.Decode<PrepareBatteryCompleteReq>(bytes),
            /*0x*/
            77 => ModelConvert.Decode<RemoteSignalReq>(bytes),
            /*0x*/
            95 => ModelConvert.Decode<InboundCommandsResq>(bytes),
            /*0x*/
            92 => ModelConvert.Decode<FaultResetResq>(bytes),
            /*0x*/
            87 => ModelConvert.Decode<PauseCommandResq>(bytes),
            /*0x*/
            84 => ModelConvert.Decode<OutboundCompleteReq>(bytes),
            /*0x*/
            107 => ModelConvert.Decode<BatteryShelfNumberReq>(bytes),
            /*0x*/
            89 => ModelConvert.Decode<InitializeCommandResq>(bytes),
            /*0x*/
            96 => ModelConvert.Decode<OutboundCommandResq>(bytes),
            /*0x*/
            116 => ModelConvert.Decode<StartMovElectricityResq>(bytes),
            /*0x*/
            80 => ModelConvert.Decode<SwapBatteryFinishReq>(bytes),
            /*0x*/
            101 => ModelConvert.Decode<TerminationOrderResq>(bytes),
            /*0x*/
            111 => ModelConvert.Decode<ElectricalConnectorsReq>(bytes),
            /*0x*/
            99 => ModelConvert.Decode<PrepareBatteryOnResq>(bytes),
            /*0x*/
            100 => ModelConvert.Decode<ParameterSettingsResq>(bytes),
            /*0x*/
            113 => ModelConvert.Decode<BatteryPackDisassembledReq>(bytes),
            /*0x*/
            88 => ModelConvert.Decode<ContinueCommandResq>(bytes),
            /*0x*/
            117 => ModelConvert.Decode<PowerTransferCompletedReq>(bytes),
            /*0x*/
            94 => ModelConvert.Decode<MoveCommandResq>(bytes),
            _ => new ASDU()
        };


        ASDU.ParseHeader(data, baseMsg);

        return baseMsg;
    }
}