app-starlock/lib/talk/startChart/p2p/p2p_manage.dart

import 'dart:async';
import 'dart:io';

import 'package:star_lock/talk/startChart/proto/rbcu.pb.dart';

class P2pManage {
  // 常量定义
  static const String testMessage = 'Hello'; // 测试消息
  static const int localPort = 0; // 绑定本地端口（0 表示由系统分配）
  static const Duration connectionTimeout = Duration(seconds: 5); // 连接超时时间
  static const List<String> localNetworkPrefixes = [
    '192.168.',
    '10.',
    '172.'
  ]; // 局域网 IP 前缀

  RbcuInfo? communicationObjectRbcuInfo;

  void init() {
    // 初始化逻辑
  }

  // 解析 address 属性，提取对方的 IP 和端口
  List<Map<String, String>> parseRemoteAddresses() {
    final addresses = communicationObjectRbcuInfo?.address ?? [];
    return addresses.map((addr) {
      final parts = addr.split(':');
      return {'ip': parts[0], 'port': parts[1]};
    }).toList();
  }

  // 判断是否为局域网 IP
  bool _isLocalNetworkIp(String ip) {
    for (final prefix in localNetworkPrefixes) {
      if (ip.startsWith(prefix)) {
        // 处理 172.16.x.x 到 172.31.x.x
        if (prefix == '172.') {
          final secondOctet = int.tryParse(ip.split('.')[1]) ?? 0;
          if (secondOctet >= 16 && secondOctet <= 31) {
            return true;
          }
        } else {
          return true;
        }
      }
    }
    return false;
  }

  // 创建 UDP 连接
  Future<void> createUdpConnection() async {
    final addresses = parseRemoteAddresses();

    // 优先使用局域网 IP
    addresses.sort((a, b) {
      final isALocal = _isLocalNetworkIp(a['ip']!);
      final isBLocal = _isLocalNetworkIp(b['ip']!);
      if (isALocal && !isBLocal) return -1; // a 是局域网 IP，优先级更高
      if (!isALocal && isBLocal) return 1; // b 是局域网 IP，优先级更高
      return 0; // 优先级相同
    });

    // 尝试连接
    for (final addr in addresses) {
      final ip = addr['ip']!;
      final port = int.parse(addr['port']!);

      try {
        final socket = await RawDatagramSocket.bind(
            InternetAddress.anyIPv4, localPort); // 绑定本地端口

        // 发送测试数据
        final testData = testMessage.codeUnits;
        socket.send(testData, InternetAddress(ip), port);

        // 设置超时时间
        final completer = Completer<void>();

        // 监听响应
        socket.listen((event) {
          if (event == RawSocketEvent.read) {
            final datagram = socket.receive();
            if (datagram != null) {
              final response = String.fromCharCodes(datagram.data);
              print('收到来自 $ip:$port 的响应: $response');
              completer.complete(); // 收到响应，完成 Future
            }
          }
        });

        // 等待响应或超时
        try {
          await completer.future.timeout(connectionTimeout);
          print('成功连接到 $ip:$port');
          return; // 连接成功，退出循环
        } on TimeoutException {
          print('连接到 $ip:$port 超时');
        } finally {
          socket.close(); // 关闭 socket
        }
      } catch (e) {
        print('连接到 $ip:$port 失败: $e');
      }
    }

    print('无法连接到任何地址');
  }
}