llbzow 的摸鱼日记 (づ￣ 3￣)づ

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import 'dart:math' as math;
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enum CoordinateUnit { degrees, radiansConverted }
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class NormalizedCoordinates {
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  final double latitude;
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  final double longitude;
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  final CoordinateUnit detectedUnit;
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  const NormalizedCoordinates({
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    required this.latitude,
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    required this.longitude,
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    required this.detectedUnit,
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  });
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}
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class AllowedArea {
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  final double minLatitude;
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  final double maxLatitude;
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  final double minLongitude;
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  final double maxLongitude;
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  const AllowedArea({
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    required this.minLatitude,
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    required this.maxLatitude,
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    required this.minLongitude,
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    required this.maxLongitude,
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  });
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  bool contains(double latitude, double longitude) =>
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      latitude >= minLatitude &&
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      latitude <= maxLatitude &&
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      longitude >= minLongitude &&
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      longitude <= maxLongitude;
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}
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/**
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 * 自适应纠偏 NMEA/物联网定位坐标
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 */
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NormalizedCoordinates normalizeLocationCoordinates({
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  required double rawLatitude,
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  required double rawLongitude,
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  required AllowedArea allowedArea,
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}) {
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  // 缺省状态假设输入为正常的 "度"
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  var targetLatitude = rawLatitude;
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  var targetLongitude = rawLongitude;
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  var detectedUnit = CoordinateUnit.degrees;
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  if (rawLatitude.isFinite && rawLongitude.isFinite) {
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    // 1. 判断是否落入合理的弧度物理上限区间
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    // 纬度绝对值不超过 pi/2 + 0.01 且经度绝对值不超过 pi + 0.01
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    final bool isPlausibleRadians = rawLatitude.abs() <= (math.pi / 2 + 0.01) &&
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                                    rawLongitude.abs() <= (math.pi + 0.01);
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    if (isPlausibleRadians) {
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      // 2. 尝试执行弧度转度的数学计算
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      final degreeLatitude = rawLatitude * 180 / math.pi;
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      final degreeLongitude = rawLongitude * 180 / math.pi;
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      // 3. 作业区来自受控配置，示例不包含真实边界
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      final bool isInsideAllowedArea =
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          allowedArea.contains(degreeLatitude, degreeLongitude);
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      if (isInsideAllowedArea) {
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        // 4. 符合全部判据，判定为异常输出的弧度数据，自动纠错
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        targetLatitude = degreeLatitude;
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        targetLongitude = degreeLongitude;
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        detectedUnit = CoordinateUnit.radiansConverted;
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        print(">>> [纠偏警告] 探测到定位单位冲突，已按授权规则转换；坐标值不写入日志。");
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      }
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    }
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  }
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  return NormalizedCoordinates(
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    latitude: targetLatitude,
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    longitude: targetLongitude,
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    detectedUnit: detectedUnit,
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  );
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}