[tutorial] Abstract factory pattern

#include <string>
#include <iostream>


/* Common utility */
bool icompare_pred(unsigned char a, unsigned char b)
{
    return std::tolower(a) == std::tolower(b);
}

bool icompare(std::string const& a, std::string const& b)
{
    if (a.length() == b.length()) {
        return std::equal(b.begin(), b.end(),
            a.begin(), icompare_pred);
    }
    else {
        return false;
    }
}

/* Base code for car factory */
class ICar
{
public:
    virtual std::string GetModel() = 0;
    virtual std::string GetMaker() = 0;
};

class ICarFactory
{
public:
    virtual ICar* GetRacingCar() = 0;
    virtual ICar* GetSedan() = 0;
    virtual ICar* GetHatch() = 0;
};

/* Holden and its car range*/
namespace Holden
{

    class IHoldenCar
    {
    public:
        virtual std::string GetModel() = 0;

        virtual std::string GetMaker()
        {
            return "Holden";
        }
    };

}

namespace Holden
{

    class CCommodore : public IHoldenCar
    {
    public:
        std::string GetModel()
        {
            return std::string("Commodore");
        }
    };

}

namespace Holden
{
    class CBarina : public IHoldenCar
    {
    public:
        std::string GetModel()
        {
            return std::string("Barina");
        }
    };
}

namespace Holden
{

    class CMonaro : public IHoldenCar
    {
    public:
        std::string GetModel()
        {
            return std::string("Monaro");
        }
    };

}

/* Ford and its car range*/
namespace Ford
{

    class IFordCar
    {
    public:
        virtual std::string GetModel() = 0;

        virtual std::string GetMaker()
        {
            return "Ford";
        }
    };

}

namespace Ford
{

    class CBaddGT : public IFordCar
    {
    public:
        std::string GetModel()
        {
            return std::string("Badd GT");
        }
    };

}

namespace Ford
{

    class CFalcon : public IFordCar
    {
    public:
        std::string GetModel()
        {
            return std::string("Falcon");
        }
    };

}

namespace Ford
{

    class CFocus : public IFordCar
    {
    public:
        std::string GetModel()
        {
            return std::string("Focus");
        }
    };

}

/* Holden car factory */
class CHoldenCarFactory : public ICarFactory
{
public:
    ICar* GetRacingCar()
    {
        return (ICar*)(new Holden::CMonaro());
    }

    ICar* GetSedan()
    {
        return (ICar*)(new Holden::CCommodore());
    }

    ICar* GetHatch()
    {
        return (ICar*)(new Holden::CBarina());
    }
};


/* Ford car factory */
class CFordCarFactory : public ICarFactory
{
public:
    ICar* GetRacingCar()
    {
        return (ICar*)(new Ford::CBaddGT());
    }

    ICar* GetSedan()
    {
        return (ICar*)(new Ford::CFalcon());
    }

    ICar* GetHatch()
    {
        return (ICar*)(new Ford::CFocus());
    }
};

/* Abstract factory */
class CAbstractFactory
{
public:
    ICarFactory* GetCarFactory(std::string choice)
    {
        if (icompare(choice, "Ford"))
            return (ICarFactory*)(new CFordCarFactory());

        else if (icompare(choice, "Holden"))
            return (ICarFactory*)(new CHoldenCarFactory());
    }
};

int main(void)
{
    CAbstractFactory kAbstractFactory;

    ICarFactory* pkFactory = kAbstractFactory.GetCarFactory("Holden");
    ICar* pkRacing = pkFactory->GetSedan();

    std::cout << pkRacing->GetMaker() << "\n" << pkRacing->GetModel() << " " << std::endl;

    return 0;
}