向购物车添加菜品、删除菜品、展示购物车数据

package com.itheima.controller;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.itheima.common.BaseContext;
import com.itheima.common.R;
import com.itheima.entity.ShoppingCart;
import com.itheima.service.ShoppingCartService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.web.bind.annotation.*;

import javax.xml.ws.soap.Addressing;
import java.time.LocalDateTime;
import java.util.List;

@Slf4j
@RestController
@RequestMapping("/shoppingCart")
public class ShoppingCartController {

    @Autowired
    private ShoppingCartService shoppingCartService;





    /**
     * 添加购物车
     * @param shoppingCart
     * @return
     */
    @PostMapping("/add")
    public R<ShoppingCart> add(@RequestBody ShoppingCart shoppingCart){
        log.info("购物车数据:{}", shoppingCart);
        //设置用户id,指定当前是哪个用户的购物车数据
        long currentId = BaseContext.getCurrentId();
        shoppingCart.setUserId(currentId);

        //查询当前要添加菜品或者套餐是否已经存在购物车
        Long dishId = shoppingCart.getDishId();
        LambdaQueryWrapper<ShoppingCart> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.eq(ShoppingCart::getUserId, currentId);
        if(dishId!=null){
            //添加到购物车的是菜品
            queryWrapper.eq(ShoppingCart::getDishId, dishId);

        }else{
            //添加到购物车的是套餐
            queryWrapper.eq(ShoppingCart::getSetmealId, shoppingCart.getSetmealId());
        }
        //查询当前菜品或套餐是否在购物车中
        ShoppingCart cartServiceOne = shoppingCartService.getOne(queryWrapper);

        if(cartServiceOne!=null){
            //如果已经存在，就在原来数量基础上加一
            Integer number = cartServiceOne.getNumber();
            cartServiceOne.setNumber(number+1);
            shoppingCartService.updateById(cartServiceOne);
        }else{
            //如果不存在，则添加到购物车，数量默认就是一
            shoppingCart.setNumber(1);
            shoppingCart.setCreateTime(LocalDateTime.now());
            shoppingCartService.save(shoppingCart);
            cartServiceOne = shoppingCart;
        }

        return R.success(cartServiceOne);
    }

    /**
     * 将菜品或套餐数量减一
     * @param shoppingCart
     * @return
     */
    @PostMapping("/sub")
    public R<String> sub(@RequestBody ShoppingCart shoppingCart){
        Long dishId = shoppingCart.getDishId();
        LambdaQueryWrapper<ShoppingCart> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.eq(ShoppingCart::getUserId, BaseContext.getCurrentId());
        if(dishId!=null){
            //找到给菜品
            queryWrapper.eq(ShoppingCart::getDishId, dishId);
            ShoppingCart dish = shoppingCartService.getOne(queryWrapper);
            if(dish.getNumber()==1){
                //数量为1时则删除该菜品
                shoppingCartService.remove(queryWrapper);
            }else{
                //否则将该菜品数量减一
                dish.setNumber(dish.getNumber()-1);
                shoppingCartService.updateById(dish);
            }
        }else{
            //找到套餐
            queryWrapper.eq(ShoppingCart::getSetmealId, shoppingCart.getSetmealId());
            ShoppingCart setmeal = shoppingCartService.getOne(queryWrapper);
            if(setmeal.getNumber()==1){
                //数量为1时则删除该套餐
                shoppingCartService.remove(queryWrapper);
            }else{
                setmeal.setNumber(setmeal.getNumber()-1);
                shoppingCartService.updateById(setmeal);
            }

        }
        return R.success("修改成功");
    }



    /**
     * 查看购物车
     * @return
     */
    @GetMapping("/list")
    public R<List<ShoppingCart>> list(){
        long currentId = BaseContext.getCurrentId();
        LambdaQueryWrapper<ShoppingCart> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.eq(ShoppingCart::getUserId, currentId);
        queryWrapper.orderByAsc(ShoppingCart::getCreateTime);
        List<ShoppingCart> list = shoppingCartService.list(queryWrapper);
        return R.success(list);
    }


    /**
     * 清空购物车
     * @return
     */
    @DeleteMapping("/clean")
    public R<String> clean(){
        LambdaQueryWrapper<ShoppingCart> queryWrapper = new LambdaQueryWrapper<>();
        queryWrapper.eq(ShoppingCart::getUserId, BaseContext.getCurrentId());
        shoppingCartService.remove(queryWrapper);
        return R.success("清空购物车成功");

    }

}