!7

cmodule HeadphoneDetection > DynBigNumber {
  Bool pluggedIn; // null if unknown
  int minValue = 100, maxValue;
  
  start {
    setDescription("HEADPHONES");
    if (!isLinux()) ret with setValue("Linux only, sorry");
    doEveryAndNow(10.0, r actualUpdate);
    dm_registerAs('headphoneDetector);
  }
  
  void actualUpdate enter {
    //time "Headphone detect" {
      int raw = linux_rawHeadphonesCount();
      setField(minValue := min(minValue, raw));
      setField(maxValue := max(maxValue, raw));
      if (setField(pluggedIn := minValue == maxValue ? null : raw > minValue))
        vmBus_sendMessage('headphoneChange, pluggedIn);
      setValue(nullFalseTrue(pluggedIn, 
        "Please plug/unplug headphones once to enable detection",
        "NO", "YES"));
    //}
  }
  
  // API
  
  Bool headphonesDetected() { ret pluggedIn; }
}

Began life as a copy of #1020549