createMapping method

Implementation

Future<void> createMapping(
  MidiMapping mapping,
) async {
  final response = websocket.stream
      .where((event) => event is MidiCreateResponse)
      .map((event) => event as MidiCreateResponse)
      .map(
        (event) => event.mapping,
      )
      .where((event) => event.mapping == mapping)
      .timeout(responseTimeout)
      .first;

  // FIXME: optimistically add the mapping to the UI state
  /*
  __mappings[mapping.id] = mapping.mapping;
  notifyListeners();
   */

  final message = MidiApiMessage.createRequest(mapping: mapping);
  websocket.sink.add(message);

  try {
    final responseMapping = await response;
    __mappings[responseMapping.id] = responseMapping.mapping;
    notifyListeners();
  } on TimeoutException {
    // FIXME: rollback optimistic update
    /*
    __mappings.remove(mapping.id);
    notifyListeners();
     */
  }
}