public State AddState(StateTransitMode mode_ = StateTransitMode.Automatic)
        {
            var state = new State(_states.Count, mode_);

            _states.Add(state);
            return(state);
        }
 public State(int id_, StateTransitMode mode_)
 {
     Id           = id_;
     _transitions = new List <Transition>(2);
     _mode        = mode_;
 }