GPSTracker

GPSTracker.js

class GPSTracker {
  constructor(gpsData = [], geofenceBounds = null, requirements = { minDistance: 1, minSpeed: 5 }) {
    this.gpsData = gpsData;
    this.geofenceBounds = geofenceBounds;
    this.requirements = requirements;
  }

  // Haversine 距离计算
  static haversine(lat1, lng1, lat2, lng2) {
    const R = 6371e3; // 地球半径（米）
    const φ1 = lat1 * Math.PI / 180;
    const φ2 = lat2 * Math.PI / 180;
    const Δφ = (lat2 - lat1) * Math.PI / 180;
    const Δλ = (lng2 - lng1) * Math.PI / 180;
    const a = Math.sin(Δφ / 2) ** 2 + Math.cos(φ1) * Math.cos(φ2) * Math.sin(Δλ / 2) ** 2;
    return R * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
  }

  // 计算总指标
  calculateMetrics() {
    if (this.gpsData.length < 2) return { error: "至少需要两个数据点" };
    
    let totalDistance = 0, totalTime = 0;
    for (let i = 1; i < this.gpsData.length; i++) {
      const prev = this.gpsData[i - 1];
      const curr = this.gpsData[i];
      totalDistance += GPSTracker.haversine(prev.lat, prev.lng, curr.lat, curr.lng);
      totalTime += (new Date(curr.time) - new Date(prev.time)) / 1000; // 秒
    }
    
    return {
      totalDistance: totalDistance / 1000, // 转为公里
      totalTime: totalTime / 3600,         // 转为小时
      avgSpeed: (totalDistance / 1000) / (totalTime / 3600) || 0
    };
  }

  // 验证是否达标
  checkRequirements() {
    const metrics = this.calculateMetrics();
    if (metrics.error) return metrics;
    
    return {
      isDistanceMet: metrics.totalDistance >= this.requirements.minDistance,
      isSpeedMet: metrics.avgSpeed >= this.requirements.minSpeed,
      ...metrics
    };
  }

  // 验证是否在围栏内
  validateGeofence() {
    if (!this.geofenceBounds) return { error: "未定义地理围栏" };
    
    const { minLat, maxLat, minLng, maxLng } = this.geofenceBounds;
    return this.gpsData.every(point => 
      point.lat >= minLat && 
      point.lat <= maxLat && 
      point.lng >= minLng && 
      point.lng <= maxLng
    );
  }

  // 新增：检测异常停留
  detectStops(maxStopDistance = 10, maxStopTime = 300) { // 默认：10米内停留>5分钟
    const stops = [];
    let currentStop = null;

    for (let i = 1; i < this.gpsData.length; i++) {
      const prev = this.gpsData[i - 1];
      const curr = this.gpsData[i];
      const distance = GPSTracker.haversine(prev.lat, prev.lng, curr.lat, curr.lng);
      const timeDiff = (new Date(curr.time) - new Date(prev.time)) / 1000;

      // 发现停留开始
      if (distance <= maxStopDistance && timeDiff > maxStopTime) {
        if (!currentStop) {
          currentStop = {
            start: prev.time,
            location: { lat: prev.lat, lng: prev.lng },
            duration: 0
          };
        }
        currentStop.duration += timeDiff;
        currentStop.end = curr.time;
      } else if (currentStop) {
        // 停留结束
        stops.push({
          ...currentStop,
          location: this._averageLocation([prev, curr])
        });
        currentStop = null;
      }
    }

    return stops;
  }

  // 新增：分段配速分析
  analyzeSegments() {
    const segments = [];
    for (let i = 1; i < this.gpsData.length; i++) {
      const prev = this.gpsData[i - 1];
      const curr = this.gpsData[i];
      const distance = GPSTracker.haversine(prev.lat, prev.lng, curr.lat, curr.lng) / 1000;
      const time = (new Date(curr.time) - new Date(prev.time)) / 1000 / 60; // 分钟
      segments.push({
        pace: time / distance,
        speed: distance / (time / 60),
        start: prev.time,
        end: curr.time
      });
    }
    return segments;
  }

  // 辅助方法：计算平均坐标
  _averageLocation(points) {
    const sum = points.reduce((acc, p) => {
      acc.lat += p.lat;
      acc.lng += p.lng;
      return acc;
    }, { lat: 0, lng: 0 });
    return {
      lat: sum.lat / points.length,
      lng: sum.lng / points.length
    };
  }

  // 更新后的总结果报告
  getResult() {
    return {
      requirements: this.checkRequirements(),
      geofence: this.validateGeofence(),
      stops: this.detectStops(),
      segments: this.analyzeSegments()
    };
  }
}

test.js

// 示例数据（替换为你的实际数据）
const myGPSData = [
  { lat: 22.2823, lng: 114.1865, time: "2023-10-05T08:00:00Z" },
  { lat: 22.2826, lng: 114.1869, time: "2023-10-05T08:05:00Z" },
  { lat: 22.2818, lng: 114.1872, time: "2023-10-05T08:15:00Z" }
];

// 定义地理围栏（可选）
const victoriaParkBounds = {
  minLat: 22.2810,
  maxLat: 22.2836,
  minLng: 114.1848,
  maxLng: 114.1876
};

// 创建实例
const tracker = new GPSTracker(
  myGPSData,
  victoriaParkBounds,
  { minDistance: 1, minSpeed: 5 } // 目标：至少1公里，配速≥5km/h
);

// 获取完整报告
console.log("跑步验证结果:", tracker.getResult());

// 直接读取指标
const metrics = tracker.calculateMetrics();
console.log(`总距离: ${metrics.totalDistance.toFixed(2)} km`);
console.log(`平均速度: ${metrics.avgSpeed.toFixed(2)} km/h`);

// 控制台输出结果：
// 跑步验证结果: {
//   requirements: {
//     isDistanceMet: true,
//     isSpeedMet: false,
//     totalDistance: 0.82,
//     totalTime: 0.25,
//     avgSpeed: 3.28
//   },
//   geofence: true
// }

// 检测所有超过3分钟的停留
console.log("异常停留:", tracker.detectStops(10, 180));

const dataWithStops = [
  { lat: 22.2823, lng: 114.1865, time: "2023-10-05T08:00:00Z" },
  { lat: 22.2823, lng: 114.1865, time: "2023-10-05T08:05:00Z" }, // 原地停留5分钟
  { lat: 22.2823, lng: 114.1866, time: "2023-10-05T08:10:00Z" }, // 轻微移动
  { lat: 22.2823, lng: 114.1865, time: "2023-10-05T08:15:00Z" }, // 再次停留5分钟
];
const tracker = new GPSTracker(dataWithStops);

// 输出示例：
// [
//   {
//     start: "2023-10-05T08:00:00Z",
//     end: "2023-10-05T08:05:00Z",
//     duration: 300,
//     location: { lat: 22.2823, lng: 114.1865 }
//   },
//   {
//     start: "2023-10-05T08:10:00Z",
//     end: "2023-10-05T08:15:00Z",
//     duration: 300,
//     location: { lat: 22.2823, lng: 114.18655 }
//   }
// ]

// 查看分段配速
console.log("分段配速:", tracker.analyzeSegments());