CallCenter_Dispatch.dart

dispatchCall(Call call) {
    Responder processor;
    for (var i = 0; i < allProcessors.length; i++) {
      try {
        processor = allProcessors[i].firstWhere((Responder p) => !p.isBusy());
      } catch (e) {
        print('Switching to next level');
        continue;
      }
      if (processor != null) {
        break;
      }
    }
    // if all processors are busy we add call to queue
    if (processor == null) {
      queueCalls.add(call);
    } else {
      processor.respondToCall(call);
      // we add a callback listener to now when the call is ended to
      // check the queue and do other stuff in CallCenter
      call.addEndCallback(callEnded);
    }
  }