/**
   * Accept offers as advised by the launch coordinator.
   *
   * <p>Acceptance is routed through the RM to update the persistent state before forwarding the
   * message to Mesos.
   */
  private void acceptOffers(AcceptOffers msg) {

    try {
      List<TaskMonitor.TaskGoalStateUpdated> toMonitor = new ArrayList<>(msg.operations().size());

      // transition the persistent state of some tasks to Launched
      for (Protos.Offer.Operation op : msg.operations()) {
        if (op.getType() != Protos.Offer.Operation.Type.LAUNCH) {
          continue;
        }
        for (Protos.TaskInfo info : op.getLaunch().getTaskInfosList()) {
          MesosWorkerStore.Worker worker = workersInNew.remove(extractResourceID(info.getTaskId()));
          assert (worker != null);

          worker = worker.launchWorker(info.getSlaveId(), msg.hostname());
          workerStore.putWorker(worker);
          workersInLaunch.put(extractResourceID(worker.taskID()), worker);

          LOG.info(
              "Launching Mesos task {} on host {}.",
              worker.taskID().getValue(),
              worker.hostname().get());

          toMonitor.add(new TaskMonitor.TaskGoalStateUpdated(extractGoalState(worker)));
        }
      }

      // tell the task router about the new plans
      for (TaskMonitor.TaskGoalStateUpdated update : toMonitor) {
        taskRouter.tell(update, self());
      }

      // send the acceptance message to Mesos
      schedulerDriver.acceptOffers(msg.offerIds(), msg.operations(), msg.filters());
    } catch (Exception ex) {
      fatalError("unable to accept offers", ex);
    }
  }