C# 设计一个可变长度的数据通信协议编码和解码代码。

设计一个可变长度的数据通信协议编码和解码代码。
要有本机ID字段，远端设备ID字段，指令类型字段，数据体字段，校验字段。其中一个要求是，每次固定收发八个字节，单个数据帧超过八个字节需要分包收发。对接收的数据帧要先存入环形缓存区，解码函数需要对环形缓存区中的协议数据持续解码，直到没有数据。解析出的数据最后逐个列出来，验证对错。对于存在的丢包问题，要求有重发机制。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;namespace edcode_s
{/** Packet 类表示一个数据包，* 包含本地ID、远程ID、命令类型、数据长度和数据内容等字段。*/class Packet{public byte LocalID;public byte RemoteID;public byte CommandType;public byte DataLength;public byte[] Data = new byte[255];public ushort CRC;}/** RingBuffer 类实现了一个环形缓冲区，* 用于存储发送和接收的数据。* 它有一个固定大小的缓冲区，* 通过添加和读取操作来管理数据。*/class RingBuffer{private const int BufferSize = 1024;private byte[] buffer = new byte[BufferSize];private int start = 0;private int end = 0;/** Add方法* 将给定的字节数组data中的数据按顺序添加到循环缓冲区中，* 直到填满整个缓冲区或达到指定的length长度。*/public void Add(byte[] data, int length){for (int i = 0; i < length; i++){buffer[end] = data[i];end = (end + 1) % BufferSize;}}/** Read方法* 从循环缓冲区中读取指定长度的数据，* 并将其存储到给定的字节数组中，* 从指定的偏移量开始存储。* 如果没有读取到任何数据（即缓冲区为空），* 则返回0；否则返回1表示成功读取了数据。*/public int Read(byte[] data, int offset, int length){if (IsEmpty())return 0;for (int i = 0; i < length; i++){data[offset + i] = buffer[start];start = (start + 1) % BufferSize;}return 1;}public bool IsEmpty(){return start == end;}}/** Protocol 类是通信协议的核心部分，* 负责发送和接收数据包。* 它使用 RingBuffer 来存储发送和接收的数据。*/class Protocol{private const int PacketSize = 8;private RingBuffer ringBuffer = new RingBuffer();private Random rand = new Random();/** SendPacket 方法将一个 Packet 对象转换为字节数组，并计算CRC校验码，* 然后将数据分块发送到缓冲区中。* 如果模拟了数据包丢失的情况，则会重新发送数据包。* */public void SendPacket(Packet packet){int totalLength = 4 + packet.DataLength + 2;    byte[] buffer = new byte[totalLength];buffer[0] = packet.LocalID;buffer[1] = packet.RemoteID;buffer[2] = packet.CommandType;buffer[3] = packet.DataLength;Array.Copy(packet.Data, 0, buffer, 4, packet.DataLength);ushort crc = ComputeCRC(buffer, totalLength - 2);//变量crc转换为字节数组，并将该字节数组复制到buffer字节数组中。//totalLength - 2 表示从 buffer 数组的索引位置 totalLength - 2 开始粘贴数据BitConverter.GetBytes(crc).CopyTo(buffer, totalLength - 2);for (int i = 0; i < totalLength; i += PacketSize){int chunkSize = Math.Min(PacketSize, totalLength - i);byte[] chunk = new byte[chunkSize];Array.Copy(buffer, i, chunk, 0, chunkSize);if (!SimulatePacketLoss(0.1f)) // 10% packet loss rate{ringBuffer.Add(chunk, chunkSize);}else{Console.WriteLine("Packet loss occurred, resending...");ResendPacket(chunk, chunkSize);}}}/** DecodePacket 方法从缓冲区中读取数据，* 解析出数据包的各个字段，* 并进行CRC校验。如果校验成功，则返回 true，否则返回 false。*/public bool DecodePacket(out Packet packet){packet = new Packet();if (ringBuffer.IsEmpty())return false;byte[] header = new byte[4];ringBuffer.Read(header, 0, 4);packet.LocalID = header[0];packet.RemoteID = header[1];packet.CommandType = header[2];packet.DataLength = header[3];packet.Data = new byte[packet.DataLength];ringBuffer.Read(packet.Data, 0, packet.DataLength);ushort receivedCRC;byte[] crcBytes = new byte[2];ringBuffer.Read(crcBytes, 0, 2);receivedCRC = BitConverter.ToUInt16(crcBytes, 0);byte[] fullPacket = new byte[4 + packet.DataLength];Array.Copy(header, 0, fullPacket, 0, 4);//将一个数组packet.Data的从0位置开始的长度为packet.DataLength的内容复制到另一个数组fullPacket的4位置。Array.Copy(packet.Data, 0, fullPacket, 4, packet.DataLength);ushort computedCRC = ComputeCRC(fullPacket, fullPacket.Length);if (receivedCRC != computedCRC){Console.WriteLine("CRC error");return false;}return true;}/** ResendPacket 方法将数据包重新添加到缓冲区中，以便重新发送。*/private void ResendPacket(byte[] data, int length){ringBuffer.Add(data, length);}/** SimulatePacketLoss 方法根据给定的丢包率随机决定是否模拟数据包丢失。*/private bool SimulatePacketLoss(float lossRate){return rand.NextDouble() < lossRate;//生成一个0到1之间的随机小数，并将其与lossRate进行比较。}/** ComputeCRC 方法计算给定数据的CRC校验码（CRC-16）。*/private ushort ComputeCRC(byte[] data, int length){/** 变量crc初始化为0xFFFF。然后使用两个嵌套的循环来遍历数据并计算CRC值。* 外层循环遍历整个数据数组，内层循环处理每个字节的每一位。* 在内层循环中，首先检查crc的最低位是否为1。* 如果是1，则将crc右移一位并与0xA001进行异或操作；* 否则，直接将crc右移一位。*///CRC寄存器被初始化0xFFFF。ushort crc = 0xFFFF;for (int i = 0; i < length; i++){//将数据的第一个字节（8位）与CRC寄存器的当前值进行异或运算，并将结果存回CRC寄存器。crc ^= data[i];//根据最低有效位（LSB）是否为0来决定下一步操作。//如果LSB为0，则直接将CRC寄存器的内容右移一位；//如果LSB为1，则在右移一位后，//还需要与一个特定的16位多项式（如0xA001）进行异或运算。for (int j = 0; j < 8; j++){if ((crc & 1) != 0)crc = (ushort)((crc >> 1) ^ 0xA001);elsecrc >>= 1;}}return crc;}}/** Program 类是程序的入口点，创建一个 Protocol 对象，* 构造一个 Packet 对象，然后发送该数据包，* 并尝试解码接收到的数据包。*/class Program{static void Main(string[] args){Protocol protocol = new Protocol();Packet packet = new Packet();packet.LocalID = 1;packet.RemoteID = 2;packet.CommandType = 0x01;packet.Data = new byte[] { 0x11, 0x22, 0x33, 0x44, 0x55,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0xaa,0xbb,0xff };packet.DataLength = byte.Parse(packet.Data.Length.ToString());protocol.SendPacket(packet);if (protocol.DecodePacket(out Packet received)){Console.WriteLine("Packet received successfully:");Console.WriteLine($"Local ID: {received.LocalID}");Console.WriteLine($"Remote ID: {received.RemoteID}");Console.WriteLine($"Command Type: {received.CommandType:X2}");Console.WriteLine($"Data Length: {received.DataLength}");Console.Write("Data: ");for (int i = 0; i < received.DataLength; i++){Console.Write($"{received.Data[i]:X2} ");}Console.WriteLine();}else{Console.WriteLine("Failed to decode packet or CRC error occurred.");}Console.ReadKey();}}}