day84:luffy:优惠活动策略&用户认证&购物车商品的勾选/结算

class Course:
    
    def activity(self):
        import datetime
        now = datetime.datetime.now()
        
        # 获取课程参加的活动名称
        activity_list = self.activeprices.filter(is_show=True, is_deleted=False, active__start_time__lte=now, active__end_time__gte=now)
        return activity_list

    # 优惠类型名称
    def discount_name(self):
        dis_name = ''
        a = self.activity()
        if a:
            discount_n_list = []
            for i in a:
                # 获取课程的折扣类型名称
                discount_n = i.discount.discount_type.name
                discount_n_list.append(discount_n)
            dis_name = discount_n_list[0]

        return dis_name

class CourseModelSerializer:
    field = [,discount_name]

class CourseDetailModelSerializer:
    field = [,discount_name]

USE_TZ = False # 修改时区

class Course:
    def real_price(self):
        price = float(self.price) # 获取真实价格
        r_price = price 

        a = self.activity() # 获取课程对应的活动名称
        if a: # 如果课程参加了活动
            sale = a[0].discount.sale # 查看活动对应的优惠公式
            condition_price = a[0].discount.condition # 查看活动对应的满足优惠的价格条件
            # 限时免费
            if not sale.strip():
                r_price = 0

            # 限时折扣  *0.5
            elif '*' in sale.strip():
                if price >= condition_price:
                    _, d = sale.split('*')
                    r_price = price * float(d)
            # 限时减免  -100
            elif sale.strip().startswith('-'):
                if price >= condition_price:
                    _, d = sale.split('-')
                    r_price = price - float(d)
            # 满减 满100-15
            elif '满' in sale:
                if price >= condition_price: # 只有价格满足优惠条件价格才能满减
                    l1 = sale.split('\r\n')
                    dis_list = []  #10 50  25
                    for i in l1:
                        a, b = i[1:].split('-')

                        # 当商品价格(400) 满足100-200-300 应该选择满300那个优惠
                        if price >= float(a):
                            dis_list.append(float(b))

                    max_dis = max(dis_list) # 取到最大的那个满减优惠
                    r_price = price - max_dis # 原价格-满减价格=真实价格

        return r_price

class CourseModelSerializer:
    field = [,discount_name,real_price]

class CourseDetailModelSerializer:
    field = [,discount_name,real_price]

<!-- Course.vue -->
<div class="pay-box">
    <span class="discount-type" v-if="course.discount_name">{{course.discount_name}}</span>
    <span class="discount-price">￥{{course.real_price}}元</span>
    <span class="original-price" v-if="course.discount_name">原价：{{course.price}}元</span>
    <span class="buy-now">立即购买</span>
</div>
    

<!-- Detail.vue -->
<div class="sale-time">
    <p class="sale-type">{{course_data.discount_name}}</p>
    <p class="expire">距离结束：仅剩 567 天 12小时 52分 <span class="second">32</span> 秒</p>
</div>
<p class="course-price">
    <span>活动价</span>
    <span class="discount">¥{{course_data.real_price}}</span>
    <span class="original">¥{{course_data.price}}</span>
</p>

class Course:
    def left_time(self):
        import datetime
        now = datetime.datetime.now().timestamp() # 获取当前时间戳
        left_t = 0
        a = self.activity() # 获取当前课程参加的活动
        if a: # 如果当前课程有参加活动
            end_time = a[0].active.end_time.timestamp() # 获取当前课程活动的结束时间
            left_t = end_time - now # 剩余时间=结束时间-当前时间

            return left_t

class CourseDetailModelSerializer:
    field = [,discount_name,real_price,left_time]

<!-- html -->
<div class="sale-time">
    <p class="sale-type">{{course_data.discount_name}}</p>
    <p class="expire">距离结束：仅剩 {{course_data.left_time/60/60/24 | pInt}}天 {{course_data.left_time/60/60 % 24| pInt}}小时 {{course_data.left_time/60 % 60 | pInt}}分 <span class="second">{{course_data.left_time % 60 | pInt}}</span> 秒</p>
</div>

get_course_data(){
        this.$axios.get(`${this.$settings.Host}/course/detail/${this.course_id}/`)
        .then((res)=>{
          //console.log(res.data);
          this.course_data = res.data;
          this.playerOptions.sources[0].src = res.data.course_video
          this.playerOptions.poster = res.data.course_img

         // 设置计时器
          setInterval(()=>{
            this.course_data.left_time--;

          },1000)

        })
      },

<!-- Detail.vue--html -->
         <p class="expire">距离结束：仅剩 {{course_data.left_time/60/60/24 | pInt}}天 
{{course_data.left_time/60/60 % 24| pInt}}小时 
{{course_data.left_time/60 % 60 | pInt}}分 
<span class="second">{{course_data.left_time % 60 | pInt}}</span> 秒</p>         

// Detail.vue--js
 filters:{
      pInt(val){
        let a = parseInt(val);
        if (a < 10){
          a = `0${a}`;
        }
        return a
      }
    }

# cart/views.py
class AddCartView:
    
    # 请求头必须携带着token
    permission_classes = [IsAuthenticated,] # 添加用户认证
    def add:
        user_id = request.user.id # 获取真实的用户id
        '''
        request = user_obj
        '''
    

// Detail.vue 添加购物车
    methods: {

      addCart(){

        let token = localStorage.token || sessionStorage.token;

        if (token){
          this.$axios.post(`${this.$settings.Host}/users/verify/`,{
              token:token,
            }).then((res)=>{
    this.$axios.post(`${this.$settings.Host}/cart/add_cart/`,{
                course_id:this.course_id,
              },{
              // 向后端提交数据需要加上header项,将token也要提交过去
              headers:{
                'Authorization':'jwt ' + token
              }
            }).then((res)=>{
                this.$message.success(res.data.msg);
                console.log('>>>>>',this.$store)
                this.$store.commit('add_cart', res.data.cart_length) ;
                console.log(this.$store.state);
              })

            }).catch((error)=>{
             ......
            })


        } else {
          ......
              })
        }

      },

// Cart.vue 购物车页面
created() {
    let token = sessionStorage.token || localStorage.token;
    if (token){

      this.$axios.get(`${this.$settings.Host}/cart/add_cart/`,{
         // 查看购物车页面也要携带token 否则不能查看
         headers:{
                'Authorization':'jwt ' + token
              }
      })
      .then((res)=>{
        this.cart_data_list = res.data.cart_data_list
      })
      .catch((error)=>{
        this.$message.error(error.response.data.msg);
      })

# cart/views.py

class AddCartView:
def cart_list(self, request):
       ......
        cart_data_list.append({
           ......
            'real_price': course_obj.real_price(),
           ......
        })
       ......

<!-- cartitem.vue -->
<div class="cart_column column_4">¥{{cart.real_price}}</div>

# cart/views.py
class AddCartView:
    def change_select(self, request):
        
        # 拿到课程id
        course_id = request.data.get('course_id')
        
        # 校验课程id合法性
        try:
            models.Course.objects.get(id=course_id)
        except:
            return Response({'msg': '课程不存在，不要乱搞！'}, status=status.HTTP_400_BAD_REQUEST)
        
        # 拿到user_id
        user_id = request.user.id
        
        # 去redis数据库：cart
        conn = get_redis_connection('cart')
        
        # redis存数据-用集合存:用户id：勾选课程id
        conn.sadd('selected_cart_%s' % user_id, course_id)
        
        return Response({'msg':'勾选成功'})   
    
       def cancel_select(self, request):
        course_id = request.data.get('course_id')

        try:
            models.Course.objects.get(id=course_id)
        except:
            return Response({'msg': '课程不存在，不要乱搞！'}, status=status.HTTP_400_BAD_REQUEST)

        user_id = request.user.id
        conn = get_redis_connection('cart')  # 1:{1,3}
        conn.srem('selected_cart_%s' % user_id, course_id)

        return Response({'msg': '恭喜你！少花钱了，但是你真的不学习了吗！'}) 

# cart/urls.py
from django.urls import path,re_path
from . import views

urlpatterns = [
    path('add_cart/', views.AddCartView.as_view({'post':'add',
'get':'cart_list',
'patch':'change_select',
'put':'cancel_select'})) # 不同的请求方法走不同函数

]

<!-- 当用户点击前面的勾选框时，会改变selected的值
近而会被watch监听到
在监听中 无论是选中还是取消选中都会触发父级标签重新计算价格的动作（this.$emit） -->
<el-checkbox class="my_el_checkbox" v-model="cart.selected"></el-checkbox>

// Cartitem.vue
watch:{

      'cart.selected':function (){
          
        // 添加选中
        let token = localStorage.token || sessionStorage.token;
        if (this.cart.selected){
          this.$axios.patch(`${this.$settings.Host}/cart/add_cart/`,{
            course_id: this.cart.course_id,

          },{
            headers:{
              'Authorization':'jwt ' + token
            }
          }).then((res)=>{
            this.$message.success(res.data.msg);
            this.$emit('cal_t_p') // 触发cart组件计算商品总价格的方法
          }).catch((error)=>{
            this.$message.error(res.data.msg);
          })
        }
        else {
            
          // 取消选中
          this.$axios.put(`${this.$settings.Host}/cart/add_cart/`,{
            course_id: this.cart.course_id,

          },{
            headers:{
              'Authorization':'jwt ' + token
            }
          }).then((res)=>{
            this.$message.success(res.data.msg);
            this.$emit('cal_t_p') // 触发cart组件计算商品总价格的方法
          }).catch((error)=>{
            this.$message.error(res.data.msg);
          })
        }
      },


    }

<!-- Cart.vue -->
 <div class="cart_course_list">
     
     <CartItem v-for="(value,index) in cart_data_list" :key="index" :cart="value" @cal_t_p="cal_total_price"></CartItem>

</div>

// Cart.vue
methods:{
    cal_total_price(){
        
        let t_price = 0
        this.cart_data_list.forEach((v,k)=>{ // v是值 k是索引
          if (v.selected){
            t_price += v.real_price
          }
        })
        this.total_price = t_price

      }
}

# cart/views.py
def cart_list(self, request):

        user_id = request.user.id

        conn = get_redis_connection('cart')

        conn.delete('selected_cart_%s' % user_id)
        ret = conn.hgetall('cart_%s' % user_id)  # dict {b'1': b'0', b'2': b'0'}
        cart_data_list = []
        
        try:
            for cid, eid in ret.items():
                course_id = cid.decode('utf-8') # 取出用户购物车里的课程id(redis中存着呢)
                expire_id = eid.decode('utf-8') # 取出用户购物车里的有效期id(redis中存着呢)

                course_obj = models.Course.objects.get(id=course_id) # 根据课程id,通过ORM查询得到课程对象，在下面就可以通过课程对象.字段 取到对应课程的参数信息

                cart_data_list.append({
                    'course_id': course_obj.id,
                    'name': course_obj.name,
                    'course_img': constants.SERVER_ADDR + course_obj.course_img.url,
                    'price': course_obj.price,
                    'real_price': course_obj.real_price(),
                    'expire_id': expire_id,
                    'selected': False,  # 默认没有勾选
                })
        except Exception:
            logger.error('获取购物车数据失败')
            return Response({'msg': '后台数据库出问题了,请联系管理员'}, status=status.HTTP_507_INSUFFICIENT_STORAGE)

        return Response({'msg': 'xxx', 'cart_data_list': cart_data_list})
    

# cart/views.py
def cart_list(self, request):
    ......
    conn = get_redis_connection('cart')
    # 用户刷新页面时,从redis中删除用户对应的课程id
    conn.delete('selected_cart_%s' % user_id)
    ret = conn.hgetall('cart_%s' % user_id)  
    ......