class StateManager
{

private:
   template <typename T>
   std::unique_ptr<State> StateFactory()
   {
      return std::unique_ptr<State>(new T());
   }

public:
   StateManager();

   template <typename T>
   void registerState(States::State state)
   {
      stateMap[state] = StateFactory<T>;
   }

   void add();
   void remove();

private:
   template <typename T>
   std::map<States::State, > stateMap;

};