/// 网络状态模型
class NetworkStatus {
  final bool isConnected;       // 是否连接
  final double downloadSpeed;   // 下载速度 (Mbps)
  final double uploadSpeed;     // 上传速度 (Mbps)
  final int latency;            // 延迟 (ms)
  final String externalIp;      // 外网IP
  final String localIp;         // 内网IP
  final DateTime lastCheck;     // 最后检测时间

  const NetworkStatus({
    this.isConnected = false,
    this.downloadSpeed = 0,
    this.uploadSpeed = 0,
    this.latency = 0,
    this.externalIp = '',
    this.localIp = '',
    required this.lastCheck,
  });

  /// 默认状态
  factory NetworkStatus.initial() {
    return NetworkStatus(lastCheck: DateTime.now());
  }

  /// 从JSON创建
  factory NetworkStatus.fromJson(Map<String, dynamic> json) {
    return NetworkStatus(
      isConnected: json['isConnected'] as bool? ?? false,
      downloadSpeed: (json['downloadSpeed'] as num?)?.toDouble() ?? 0,
      uploadSpeed: (json['uploadSpeed'] as num?)?.toDouble() ?? 0,
      latency: json['latency'] as int? ?? 0,
      externalIp: json['externalIp'] as String? ?? '',
      localIp: json['localIp'] as String? ?? '',
      lastCheck: DateTime.parse(json['lastCheck'] as String),
    );
  }

  /// 转换为JSON
  Map<String, dynamic> toJson() {
    return {
      'isConnected': isConnected,
      'downloadSpeed': downloadSpeed,
      'uploadSpeed': uploadSpeed,
      'latency': latency,
      'externalIp': externalIp,
      'localIp': localIp,
      'lastCheck': lastCheck.toIso8601String(),
    };
  }

  /// 复制并更新
  NetworkStatus copyWith({
    bool? isConnected,
    double? downloadSpeed,
    double? uploadSpeed,
    int? latency,
    String? externalIp,
    String? localIp,
    DateTime? lastCheck,
  }) {
    return NetworkStatus(
      isConnected: isConnected ?? this.isConnected,
      downloadSpeed: downloadSpeed ?? this.downloadSpeed,
      uploadSpeed: uploadSpeed ?? this.uploadSpeed,
      latency: latency ?? this.latency,
      externalIp: externalIp ?? this.externalIp,
      localIp: localIp ?? this.localIp,
      lastCheck: lastCheck ?? this.lastCheck,
    );
  }

  /// 获取网络状态描述
  String get statusDescription {
    if (!isConnected) return '网络断开';
    if (latency > 200) return '网络较慢';
    if (latency > 100) return '网络一般';
    return '网络良好';
  }

  /// 格式化下载速度
  String get downloadSpeedText {
    if (downloadSpeed >= 1000) {
      return '${(downloadSpeed / 1000).toStringAsFixed(2)} Gbps';
    }
    return '${downloadSpeed.toStringAsFixed(2)} Mbps';
  }

  /// 格式化上传速度
  String get uploadSpeedText {
    if (uploadSpeed >= 1000) {
      return '${(uploadSpeed / 1000).toStringAsFixed(2)} Gbps';
    }
    return '${uploadSpeed.toStringAsFixed(2)} Mbps';
  }
}

/// 网速历史记录
class SpeedHistory {
  final DateTime time;
  final double download;
  final double upload;

  const SpeedHistory({
    required this.time,
    required this.download,
    required this.upload,
  });
}