#pragma once
/////////////////////////////////////////////////////////////////////
// SkeletonPlus.h - Gang of Four Singleton with reference counting //
// Ver 1.1                                                         //
// Jim Fawcett, CSE776 - Design Patterns, Fall 2017                //
/////////////////////////////////////////////////////////////////////
/*
*  Ver 1.1 : 13 Sep 2017
*  - fixes bug discovered by Lakshmi Chilukuri by setting
*    pInstance to nullptr after deleting instance in Release()
*  Ver 1.0 : 11 Sep 2017
*  - first release.
*/
/////////////////////////////////////////////////////////////////////
// Singleton class
/*
*  - Guarantees, at most, one instance of Singleton will exist
*    in a single-threaded environment.
*  - Does not guarantee only one instance of singletonData!
*/
#include <string>

class Singleton
{
public:
  static Singleton* Instance();
  void SingletonOperation(const std::string& data);
  std::string GetSingletonData();
  void ReleaseInstance();
  
private:
  Singleton();
  ~Singleton();
  static Singleton* pUniqueInstance;
  std::string singletonData;
  static size_t refCount;
};

Singleton* Singleton::pUniqueInstance = nullptr;
size_t Singleton::refCount = 0;