/*]  Copyright (c) 2009-2010, Charles McGarvey  [**************************
**]  All rights reserved.
*
* vi:ts=4 sw=4 tw=75
*
* Distributable under the terms and conditions of the 2-clause BSD license;
* see the file COPYING for a complete text of the license.
*
**************************************************************************/

#ifndef _MOOF_MANAGER_HH_
#define _MOOF_MANAGER_HH_

/**
 * @file Manager.hh
 * A library is a collection of named objects of the same type.  Libraries
 * use reference counting to automagically delete objects which no longer
 * have any interested code.
 */

#include <string>

#include <boost/shared_ptr.hpp>

#include <Moof/HashTools.hh>


namespace Mf {


template <class T>
class Manager
{
public:

	Manager() :
		mRetainCount(1) {}

	const std::string& getName() const
	{
		return mName;
	}

	static boost::shared_ptr<T> getInstance(const std::string& name)
	{
		return boost::shared_ptr<T>(retain(name), &release);
	}

private:

	typedef stlplus::hash<std::string,T*,HashFunction> PtrMap;

	static PtrMap	mPtrMap;
	std::string		mName;
	unsigned		mRetainCount;

	static T* retain(const std::string& name)
	{
		typename PtrMap::iterator it = mPtrMap.find(name);

		if (it != mPtrMap.end())
		{
			++((*it).second->mRetainCount);
			return (*it).second;
		}
		else
		{
			T* newObj(new T);
			if (newObj)
			{
				newObj->mName = name;
				newObj->init(name);
				mPtrMap.insert(std::make_pair(name, newObj));
			}
			return newObj; 
		}
	}

	static void release(T* obj)
	{
		if (--(obj->mRetainCount) == 0)
		{
			mPtrMap.erase(obj->mName);
			delete obj;
		}
	}
};

template <class T>
stlplus::hash<std::string,T*,HashFunction> Manager<T>::mPtrMap;


} // namespace Mf

#endif // _MOOF_MANAGER_HH_