app-starlock/lib/talk/startChart/entity/scp_message.dart

import 'dart:convert';
import 'dart:typed_data';
import 'package:star_lock/app_settings/app_settings.dart';
import 'package:star_lock/talk/startChart/handle/scp_message_handle.dart';
import 'package:star_lock/talk/startChart/handle/scp_message_handler_factory.dart';


class ScpMessage {
  ScpMessage({
    this.ProtocolFlag,
    this.MessageType,
    this.MessageId,
    this.SpTotal,
    this.SpIndex,
    this.FromPeerId,
    this.ToPeerId,
    this.PayloadType,
    this.PayloadCRC,
    this.PayloadLength,
    this.Payload,
  });

  String? ProtocolFlag;
  int? MessageType;
  int? MessageId;
  int? SpTotal;
  int? SpIndex;
  String? FromPeerId;
  String? ToPeerId;
  int? PayloadType;
  int? PayloadCRC;
  int? PayloadLength;
  dynamic Payload; // Payload可以是任何类型，这里用dynamic表示

  ScpMessage.fromJson(dynamic json) {
    ProtocolFlag = json['ProtocolFlag'];
    MessageType = json['MessageType'];
    MessageId = json['MessageId'];
    SpTotal = json['SpTotal'];
    SpIndex = json['SpIndex'];
    FromPeerId = json['FromPeerId'];
    ToPeerId = json['ToPeerId'];
    PayloadType = json['PayloadType'];
    PayloadCRC = json['PayloadCRC'];
    PayloadLength = json['PayloadLength'];
    Payload = json['Payload'];
  }

  Map<String, dynamic> toJson() {
    return {
      'ProtocolFlag': ProtocolFlag,
      'MessageType': MessageType,
      'MessageId': MessageId,
      'SpTotal': SpTotal,
      'SpIndex': SpIndex,
      'FromPeerId': FromPeerId,
      'ToPeerId': ToPeerId,
      'PayloadType': PayloadType,
      'PayloadCRC': PayloadCRC,
      'PayloadLength': PayloadLength,
      'Payload': Payload,
    };
  }

  @override
  String toString() {
    return 'ScpMessage{ProtocolFlag: $ProtocolFlag, MessageType: $MessageType, MessageId: $MessageId, SpTotal: $SpTotal, SpIndex: $SpIndex, FromPeerId: $FromPeerId, ToPeerId: $ToPeerId, PayloadType: $PayloadType, PayloadCRC: $PayloadCRC, PayloadLength: $PayloadLength, Payload: $Payload}';
  }

  String serialize() {
    final bytes = <int>[];

    // ProtocolFlag (4 bytes)
    if (ProtocolFlag != null) {
      bytes.addAll(utf8.encode(ProtocolFlag!));
    }

    // MessageType (1 byte)
    if (MessageType != null) {
      bytes.add(MessageType!);
    }

    // MessageId (2 bytes)
    if (MessageId != null) {
      final highByteMessageId = (MessageId! >> 8) & 0xFF;
      final lowByteMessageId = MessageId! & 0xFF;
      bytes.add(lowByteMessageId); // 交换位置
      bytes.add(highByteMessageId); // 交换位置
    }

    // SpTotal (1 byte)
    if (SpTotal != null) {
      bytes.add(SpTotal!);
    }

    // SpIndex (1 byte)
    if (SpIndex != null) {
      bytes.add(SpIndex!);
    }

    // FromPeerId (字符串，记录长度)
    if (FromPeerId != null) {
      bytes.addAll(utf8.encode(FromPeerId!));
    }

    // ToPeerId (字符串，假设长度固定为32字节)
    if (ToPeerId != null) {
      bytes.addAll(utf8.encode(ToPeerId!));
    }

    // PayloadType (2 bytes)
    if (PayloadType != null) {
      final highBytePayloadType = (PayloadType! >> 8) & 0xFF;
      final lowBytePayloadType = PayloadType! & 0xFF;
      bytes.add(lowBytePayloadType); // 交换位置
      bytes.add(highBytePayloadType); // 交换位置
    }

    // 计算 PayloadCRC (2 bytes)
    if (PayloadCRC != null) {
      final highBytePayloadCRC = (PayloadCRC! >> 8) & 0xFF;
      final lowBytePayloadCRC = PayloadCRC! & 0xFF;
      bytes.add(lowBytePayloadCRC); // 交换位置
      bytes.add(highBytePayloadCRC); // 交换位置
    }

    // PayloadLength (4 bytes)
    if (PayloadLength != null) {
      bytes.add(PayloadLength! & 0xFF);
      bytes.add((PayloadLength! >> 8) & 0xFF);
      bytes.add((PayloadLength! >> 16) & 0xFF);
      bytes.add((PayloadLength! >> 24) & 0xFF);
    }

    // Payload (字符串，转换为字节)
    if (Payload != null && Payload is String) {
      bytes.addAll(utf8.encode(Payload!));
    } else if (Payload != null) {
      // 如果不是字符串则需要外部转为字节数组，这里直接添加
      bytes.addAll(Payload);
    }

    // 转16进制字符串
    final bytesToHexString = bytesToHex(bytes);

    return bytesToHexString;
  }

  static ScpMessage deserialize(Uint8List bytes) {
    final message = ScpMessage();
    int offset = 0;
    // Convert byte array to hex string with zero padding and without spaces
    // String hexString =
    //     bytes.map((b) => b.toRadixString(16).padLeft(2, '0')).join();
    //
    // // Log the hex string
    // _log(text: '原始字节数组: $hexString');

    // ProtocolFlag (4 bytes)
    if (bytes.length - offset >= 4) {
      message.ProtocolFlag = utf8.decode(bytes.sublist(offset, offset + 4));
      offset += 4;
    } else {
      throw FormatException("Invalid ProtocolFlag length");
    }

    // MessageType (1 byte)
    if (bytes.length - offset >= 1) {
      message.MessageType = bytes[offset];
      offset += 1;
    } else {
      throw FormatException("Invalid MessageType length");
    }

    // MessageId (2 bytes, little-endian)
    if (bytes.length - offset >= 2) {
      message.MessageId = (bytes[offset + 1] << 8) | bytes[offset];
      offset += 2;
    } else {
      throw FormatException("Invalid MessageId length");
    }

    // SpTotal (1 byte)
    if (bytes.length - offset >= 1) {
      message.SpTotal = bytes[offset];
      offset += 1;
    } else {
      throw FormatException("Invalid SpTotal length");
    }

    // SpIndex (1 byte)
    if (bytes.length - offset >= 1) {
      message.SpIndex = bytes[offset];
      offset += 1;
    } else {
      throw FormatException("Invalid SpIndex length");
    }

    // FromPeerId (字符串，长度固定为44字节)
    if (bytes.length - offset >= 44) {
      message.FromPeerId =
          utf8.decode(bytes.sublist(offset, offset + 44)).trimRight();
      offset += 44;
    } else {
      throw FormatException("Invalid FromPeerId length");
    }

    // ToPeerId (字符串，长度固定为44字节)
    if (bytes.length - offset >= 44) {
      message.ToPeerId =
          utf8.decode(bytes.sublist(offset, offset + 44)).trimRight();
      offset += 44;
    } else {
      throw FormatException("Invalid ToPeerId length");
    }

    // PayloadType (2 bytes, little-endian)
    if (bytes.length - offset >= 2) {
      message.PayloadType = (bytes[offset + 1] << 8) | bytes[offset];
      offset += 2;
    } else {
      throw FormatException("Invalid PayloadType length");
    }

    // PayloadCRC (2 bytes, little-endian)
    if (bytes.length - offset >= 2) {
      message.PayloadCRC = (bytes[offset + 1] << 8) | bytes[offset];
      offset += 2;
    } else {
      throw FormatException("Invalid PayloadCRC length");
    }

    // PayloadLength (4 bytes, little-endian)
    if (bytes.length - offset >= 4) {
      message.PayloadLength = (bytes[offset] |
          (bytes[offset + 1] << 8) |
          (bytes[offset + 2] << 16) |
          (bytes[offset + 3] << 24)); // 修正为 little-endian
      offset += 4;
    } else {
      throw FormatException("Invalid PayloadLength length");
    }

    // 处理其他类型的Payload
    if (message.PayloadLength != null &&
        bytes.length - offset >= message.PayloadLength!) {
      final Uint8List sublist =
          bytes.sublist(offset, offset + message.PayloadLength!);
      offset += message.PayloadLength!;
      message.Payload = _handlePayLoad(
        payloadType: message.PayloadType ?? 0,
        messageType: message.MessageType ?? 0,
        byte: sublist,
        offset: offset,
        PayloadLength: message.PayloadLength,
        spIndex: message.SpIndex,
        spTotal: message.SpTotal,
        messageId: message.MessageId,
      );
    } else {
      throw FormatException("Invalid Payload or PayloadLength");
    }

    return message;
  }

  // 根据不同payloadType序列化对应的payload结构体
  static dynamic _handlePayLoad({
    required int payloadType,
    required int messageType,
    required Uint8List byte,
    int? offset,
    int? PayloadLength,
    int? spTotal,
    int? spIndex,
    int? messageId,
  }) {
    try {
      // 构造工厂
      final ScpMessageHandler handler =
          ScpMessageHandlerFactory.createHandler(payloadType);
      // 处理荷载信息并返回
      return handler.deserializePayload(
        payloadType: payloadType,
        messageType: messageType,
        byte: byte,
        offset: offset,
        PayloadLength: PayloadLength,
        spTotal: spTotal,
        spIndex: spIndex,
        messageId: messageId,
      );
    } catch (e, stackTrace) {
      // 打印异常信息
      _log(text: '❌反序列化udp数据时遇到错误----》$e');
      // 打印堆栈跟踪信息
      _log(text: '堆栈跟踪:\n$stackTrace');
      return '';
    }
  }

  static String bytesToHex(List<int> bytes) {
    return bytes.map((byte) => byte.toRadixString(16).padLeft(2, '0')).join('');
  }

  // 辅助函数：将16进制字符串转换为字节数组
  static List<int> hexToBytes(String hexString) {
    final bytes = <int>[];
    for (int i = 0; i < hexString.length; i += 2) {
      final hexByte = hexString.substring(i, i + 2);
      bytes.add(int.parse(hexByte, radix: 16));
    }
    return bytes;
  }

  static void _log({required String text}) {
    AppLog.log('=====${text}');
  }
}