microphonePermission static method

Implementation

static Future<StreamSubscription<void>> microphonePermission() async {
  bool granted = false;

  // Firefox doesn't allow to check whether app has microphone permission:
  // https://searchfox.org/mozilla-central/source/dom/webidl/Permissions.webidl#10
  if (!isFirefox) {
    final permission =
        await web.window.navigator.permissions
            .query({'name': 'microphone'}.jsify() as JSObject)
            .toDart;
    granted = permission.state == 'granted';
  }

  if (!granted) {
    final web.MediaStream stream =
        await web.window.navigator.mediaDevices
            .getUserMedia(web.MediaStreamConstraints(audio: true.toJS))
            .toDart;

    if (isFirefox) {
      final StreamController controller = StreamController(
        onCancel: () {
          for (var e in stream.getTracks().toDart) {
            e.stop();
          }
        },
      );

      return controller.stream.listen((_) {});
    } else {
      for (var e in stream.getTracks().toDart) {
        e.stop();
      }
    }
  }

  return (const Stream.empty()).listen((_) {});
}