//##################################################################################################
//
//   Custom Visualization Core library
//   Copyright (C) 2011-2012 Ceetron AS
//    
//   This library is free software: you can redistribute it and/or modify 
//   it under the terms of the GNU General Public License as published by 
//   the Free Software Foundation, either version 3 of the License, or 
//   (at your option) any later version. 
//    
//   This library is distributed in the hope that it will be useful, but WITHOUT ANY 
//   WARRANTY; without even the implied warranty of MERCHANTABILITY or 
//   FITNESS FOR A PARTICULAR PURPOSE.   
//    
//   See the GNU General Public License at <<http://www.gnu.org/licenses/gpl.html>> 
//   for more details. 
//
//##################################################################################################

#pragma once

#include <assert.h>

namespace caf
{

class PdmObject;

//==================================================================================================
/// "Private" class for implementation of a factory for PdmObjectBase derived objects
/// Every PdmObject must register with this factory to be readable
/// This class can be considered private in the Pdm system
//==================================================================================================

class PdmObjectFactory
{
public:
    static PdmObjectFactory * instance();
    PdmObject *     create(const QString& classNameKeyword);

    template< typename PdmObjectBaseDerivative >
    bool                registerCreator()
    {
        std::map<QString, PdmObjectCreatorBase*>::iterator entryIt;

        QString classNameKeyword = PdmObjectBaseDerivative::classKeywordStatic();

        entryIt = m_factoryMap.find(classNameKeyword);
        if (entryIt == m_factoryMap.end())
        {
            m_factoryMap[classNameKeyword] = new PdmObjectCreator<PdmObjectBaseDerivative>();
            return true;
        }
        else
        {
            assert(classNameKeyword != entryIt->first); // classNameKeyword has already been used
            assert(false); // To be sure ..
            return false;  // never hit;
        }
    }

private:
    PdmObjectFactory()  {}
    ~PdmObjectFactory() { /* Could clean up, but ... */ }

    // Internal helper classes

    class PdmObjectCreatorBase
    {
    public:
        PdmObjectCreatorBase() {}
        virtual ~PdmObjectCreatorBase() {}
        virtual PdmObject * create() = 0;
    };

    template< typename PdmObjectBaseDerivative >
    class PdmObjectCreator : public PdmObjectCreatorBase
    {
    public:
        virtual PdmObject * create() { return new PdmObjectBaseDerivative(); }
    };

    // Map to store factory
    std::map<QString, PdmObjectCreatorBase*> m_factoryMap;
};


} //End of namespace caf