// test03.cpp : Defines the entry point for the console application.

//

//设计模式第3章 装饰者模式

#include "stdafx.h"

#include <string>

#include <iostream>

//#include <cstring>

using namespace std;

class Beverage

{

public:

    string description /*= "Unkown Beverage"*/;//只有静态整型常量数据成员能在类中初始化

public:

    virtual string getDescription()//必须为虚函数

    {

        return description;

    }

    virtual double cost(){return 0;} ;//必须为虚函数

};

class CondimentDecorator : public Beverage

{

    virtual string getDescription(){return NULL;} ;

};

class Espresso : public Beverage

{

public:

    Espresso()

    {

        description = "Espresso";

    }

    double cost(){

        return 1.99;

    }

};

class HouseBlend : public Beverage

{

public:

    HouseBlend()

    {

        description = "House Blend Coffee";

    }

    double cost()

    {

        return .89;

    }

};

class DarkRoast : public Beverage

{

public:

    DarkRoast()

    {

        description = "Dark Roast Coffee";

    }

    double cost()

    {

        return .99;

    }

};

class Mocha : public CondimentDecorator

{

    Beverage* beverage;

public:

    Mocha(Beverage* beverage)//必须为指针

    {

        this->beverage = beverage;

    }

    string getDescription()

    {

        return beverage->getDescription() + ", Mocha";

    }

    double cost()

    {

        return .20 + beverage->cost();

    }

};

class Whip : public CondimentDecorator

{

    Beverage* beverage;

public:

    Whip(Beverage* beverage)

    {

        this->beverage = beverage;

    }

    string getDescription()

    {

        return beverage->getDescription() + ", Whip";

    }

    double cost()

    {

        return .10 + beverage->cost();

    }

};

class Soy : public CondimentDecorator

{

    Beverage* beverage;

public:

    Soy(Beverage* beverage)

    {

        this->beverage = beverage;

    }

    string getDescription()

    {

        return beverage->getDescription() + ", Soy";

    }

    double cost()

    {

        return .15 + beverage->cost();

    }

};

int _tmain(int argc, _TCHAR* argv[])

{

    Beverage* beverage = new Espresso();

    cout<<beverage->getDescription() << " $ " << beverage->cost()<<endl;

    Beverage* beverage2 = new DarkRoast();

    beverage2 = new Mocha(beverage2);//必须传递指针

    beverage2 = new Mocha(beverage2);

    beverage2 = new Whip(beverage2);

    //printf("%s %$ %f",beverage2->getDescription(),beverage2->cost());//printf 不能输出string类型

    cout<<beverage2->getDescription()<<" $ "<<beverage2->cost()<<endl;

    Beverage* beverage3 = new HouseBlend();

    beverage3 = new Soy(beverage3);

    beverage3 = new Mocha(beverage3);

    beverage3 = new Whip(beverage3);

    //printf("%s %$ %f",beverage3->getDescription(),beverage3->cost());

    cout<<beverage3->getDescription()<<" $ "<<beverage3->cost()<<endl;

    return 0;

}