---

let speedText;
let unitText;
let isKmh = true;
let geolocation = null;

Page({
  build() {
    speedText = hmUI.createWidget(hmUI.widget.TEXT, {
      x: 20,
      y: 110,
      w: 380,
      h: 120,
      color: 0xffffff,
      text_size: 70,
      align_h: hmUI.align.CENTER,
      align_v: hmUI.align.CENTER_V,
      text: "0.0"
    });

    unitText = hmUI.createWidget(hmUI.widget.TEXT, {
      x: 20,
      y: 230,
      w: 380,
      h: 50,
      color: 0x00ff00,
      text_size: 30,
      align_h: hmUI.align.CENTER,
      align_v: hmUI.align.CENTER_V,
      text: "км/ч"
    });

    hmUI.createWidget(hmUI.widget.BUTTON, {
      x: 0,
      y: 0,
      w: 480,
      h: 480,
      text: "",
      press_color: 0x111111,
      normal_color: 0x000000,
      click_func: () => {
        isKmh = !isKmh;
        unitText.setProperty(hmUI.prop.TEXT, isKmh ? "км/ч" : "м/с");
      }
    });

    this.initGPS();
  },

  initGPS() {
    try {
      geolocation = hmSetting.createGeolocation ? hmSetting.createGeolocation() : null;
      if (geolocation) {
        geolocation.start((data) => {
          let rawSpeed = data.speed || 0;
          if (rawSpeed < 0) rawSpeed = 0;
          let displaySpeed = isKmh ? rawSpeed * 3.6 : rawSpeed;
          speedText.setProperty(hmUI.prop.TEXT, displaySpeed.toFixed(1));
        });
      }
    } catch (e) {}
  },

  onDestroy() {
    if (geolocation) {
      geolocation.stop();
    }
  }
});