/**
 * 責(zé)任鏈實現(xiàn)的關(guān)鍵是 定義一個next節(jié)點  然后構(gòu)建一個鏈?zhǔn)浇Y(jié)構(gòu)
 */
public abstract class MultyDiscount implements Discount {
    /**
     * 鏈的下一個節(jié)點
     */
    protected MultyDiscount nextMultyDiscount;
    /**
     * 通過構(gòu)造函數(shù) 將下一個節(jié)點鏈接起來
     * @param nextMultyDiscount
     */
    public MultyDiscount(MultyDiscount nextMultyDiscount){
        this.nextMultyDiscount = nextMultyDiscount;
    }
    @Override
    public int calculate(int money) {
        if (nextMultyDiscount!=null){
            this.nextMultyDiscount.calculate(money);
        }
        return money;
    }
}
public class FullMultyDiscount extends MultyDiscount{
    /**
     * 通過構(gòu)造函數(shù) 將下一個節(jié)點鏈接起來
     *
     * @param nextMultyDiscount
     */
    public FullMultyDiscount(MultyDiscount nextMultyDiscount) {
        super(nextMultyDiscount);
    }
    @Override
    public int calculate(int money) {
        /*先執(zhí)行滿減操作*/
        if (money > 200){
            System.out.println("優(yōu)惠滿減20元");
            money = money - 20;
        }
        /*父類的方法執(zhí)行的是成員變量的優(yōu)惠方案，也就是節(jié)點的優(yōu)惠方案*/
        return super.calculate(money);
    }
}
/**
 * 假日一律減5元
 */
public class HolidayMultyDiscount extends MultyDiscount {
    /**
     * 公共的下一個節(jié)點 存放在父類節(jié)點上
     * @param nextMultyDiscount
     */
    public HolidayMultyDiscount(MultyDiscount nextMultyDiscount) {
        super(nextMultyDiscount);
    }
    @Override
    public int calculate(int money) {
        if (money > 20){
            System.out.println("假日一律減5元");
            money = money - 5;
        }
        return super.calculate(money);
    }
}
/**
 * 首次購 花費多100元 減免30
 */
public class NewerMultyDiscount extends MultyDiscount {

    public NewerMultyDiscount(MultyDiscount nextMultyDiscount) {
        super(nextMultyDiscount);
    }
    @Override
    public int calculate(int money) {
        if (money > 100){
            System.out.println("首次購買減30元");
            money = money - 30;
        }
        return super.calculate(money);
    }
}
/**
 * 第二單8折優(yōu)惠
 */
public class SecondMultyDiscount extends MultyDiscount {
    public SecondMultyDiscount(MultyDiscount nextMultyDiscount) {
        super(nextMultyDiscount);
    }
    @Override
    public int calculate(int money) {
        System.out.println("第二單打8折");
        Double balance =  money * 0.8;
        return super.calculate(balance.intValue());
    }
}
public class ChainCartClient {
    /*初始化滿減優(yōu)惠券  滿減沒有下一個節(jié)點 是最后一個節(jié)點*/
    private static MultyDiscount multyDiscount = new FullMultyDiscount(null);
    static {
        /*新用戶減免優(yōu)惠是 滿減優(yōu)惠*/
        multyDiscount = new NewerMultyDiscount(multyDiscount);
        /*第二單打折扣的下一個節(jié)點是新用戶減免*/
        multyDiscount = new SecondMultyDiscount(multyDiscount);
        /*假日的下一個節(jié)點是 第二單打折扣*/
        multyDiscount = new HolidayMultyDiscount(multyDiscount);
    }
    public static void main(String[] args) {
        List<Fruit> products = new ArrayList();
        products.add(StaticFactory.getFruitApple());
        products.add(StaticFactory.getFruitBanana());
        products.add(StaticFactory.getFruitOrange());
        ShoppingCart cart = new OtherPayShopping(products);
        /*注入優(yōu)惠方案*/
        cart.setDiscount(multyDiscount);
        cart.submitOrder();
    }
}