package com.ssj.test;

import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class Shopping {
    private ShopCar shopCar ;
    public Shopping() {
        shopCar = new ShopCar();
    }
    public void add(String id , int num)
    {
        shopCar.add(id, num);
    }
    
    public void alter(String id , int num){
        shopCar.alter(id, num);
    }
    public void del(String id){
        shopCar.del(id);
    }
    /**
     * 结算
     */
    public void slmt(){
        int spend = 0;
        Set<Entry<String, Integer>> entrys = shopCar.map.entrySet();
        for (Entry<String, Integer> entry : entrys) {
            int num = entry.getValue();
            int price = Commodity.getPrice(entry.getKey());
            spend+=num*price;
            System.out.println("商品["+entry.getKey()+"],数量["+num+"],单价["+price+"],小计["+num*price+"]");
        }
        System.out.println("结算总共消费"+spend+"元");
        shopCar.map.clear();
    }
    
    class ShopCar{
        Map<String, Integer> map = new HashMap<String, Integer>();
        public void add(String id , int num){
            if(map.get(id)==null)
                map.put(id, num);
            else
                map.put(id, map.get(id)+num);
            System.out.println("增加购物车中商品["+id+"]数量为["+map.get(id)+"]");
        }
        
        public void alter(String id , int num){
            map.put(id, num);
            System.out.println("修改购物车中商品["+id+"]数量为["+num+"]");
        }
        
        public void del(String id )
        {
            map.remove(id);
            System.out.println("删除购物车中商品["+id+"]");
        }
    }
    
    static final class Commodity{
        public static final Map<String,Integer> map = new HashMap<String,Integer>();
        static{
            map.put("PAPER", 80) ;
            map.put("THOOTHBRUSH", 120) ;
            map.put("WATER", 300) ;
        }
        
        public static int getPrice(String id){
            return map.get(id);
        }
    }
    
    public static void main(String[] args) {
        Shopping shopper =  new Shopping();
        //买5个纸团
        shopper.add("PAPER", 5);
        //买2个牙刷
        shopper.add("THOOTHBRUSH", 2);
        //买2桶水
        shopper.add("WATER",2);
        //水买少了，再买10桶
        shopper.add("WATER",1);
        //算了点的手疼，直接把水改成12桶吧
        shopper.alter("WATER", 12);
        //牙刷昨天买了……删了吧
        shopper.del("THOOTHBRUSH");
        //做结算
        shopper.slmt();
    }
}