feat(buyer): 更新电子卡券（E_COUPON）相关逻辑与展示

- 优化购物车与支付页面，确保电子卡券只能通过立即购买结算
- 增强商品详情页，添加限时折扣与第N件优惠展示
- 更新促销逻辑，支持拼团与积分购买选项
- 规范化商品类型与库存提示，提升用户体验

buyer/src/pages/promotion/PointGoodsDetail.vue

@@ -2,18 +2,14 @@
   <div style="background:#fff;">
     <BaseHeader></BaseHeader>
     <Search style="border-bottom:2px solid red;"></Search>
-    <!-- <drawer></drawer> -->
     <div class="base-width cate-container">
       <el-breadcrumb>
         <el-breadcrumb-item to="/">首页</el-breadcrumb-item>
-        <el-breadcrumb-item>{{goodsMsg.pointsGoodsCategoryName}}</el-breadcrumb-item>
+        <el-breadcrumb-item>{{ goodsMsg.pointsGoodsCategoryName }}</el-breadcrumb-item>
       </el-breadcrumb>
     </div>
-    <!-- 商品信息展示 -->
     <div class="item-detail-show">
-      <!-- 详情左侧展示数据、图片，收藏、举报 -->
       <div class="item-detail-left">
-        <!-- 大图、放大镜 -->
         <div class="item-detail-big-img">
           <el-image
             v-if="goodsSku.thumbnail"
@@ -29,22 +25,22 @@
           </div>
         </div>
       </div>
-      <!-- 右侧商品信息、活动信息、操作展示 -->
       <div class="item-detail-right">
         <div class="item-detail-title">
-          <p>{{ goodsSku.goodsName }}</p>
+          <div class="item-detail-title-row">
+            <p>{{ goodsSku.goodsName }}</p>
+            <el-tag v-if="isECouponSku" class="goods-type-tag" size="small">电子卡券</el-tag>
+          </div>
         </div>
         <div class="sell-point">
-          {{goodsSku.sellingPoint}}
+          {{ goodsSku.sellingPoint }}
         </div>
-        <!-- 商品详细 -->
         <div class="item-detail-price-row">
           <div class="item-price-left">
-            <!-- 商品原价 -->
             <div class="item-price-row">
               <p>
                 <span class="item-price-title">积 &nbsp;&nbsp;&nbsp;&nbsp;分</span>
-                <span class="item-price">{{goodsMsg.points}}</span>
+                <span class="item-price">{{ goodsMsg.points }}</span>
               </p>
             </div>
           </div>
@@ -55,25 +51,37 @@
               <p>数量</p>
             </div>
             <div class="item-select-row">
-              <el-input-number :min="1" :disabled="goodsSku.quantity === 0" v-model="count"></el-input-number>
-              <span class="inventory"> 库存{{goodsSku.quantity}}</span>
+              <el-input-number
+                :min="1"
+                :max="quantityMax"
+                :disabled="isOutOfStock"
+                v-model="count"
+              />
+              <span class="inventory"> 库存{{ displayStock }}</span>
             </div>
           </div>
-          <div class="item-select" v-if="goodsSku.goodsType !== 'VIRTUAL_GOODS' && goodsSku.weight !== 0">
+          <div
+            class="item-select"
+            v-if="!isECouponSku && goodsSku.goodsType !== 'VIRTUAL_GOODS' && goodsSku.weight !== 0"
+          >
             <div class="item-select-title">
               <p>重量</p>
             </div>
             <div class="item-select-row">
-              <span class="inventory"> {{goodsSku.weight}}kg</span>
+              <span class="inventory"> {{ goodsSku.weight }}kg</span>
             </div>
           </div>
           <div class="add-buy-car">
-            <el-button type="danger" :loading="loading" :disabled="goodsSku.quantity === 0" @click="pointBuy">积分购买</el-button>
+            <el-button
+              type="danger"
+              :loading="loading"
+              :disabled="isOutOfStock"
+              @click="pointBuy"
+            >积分购买</el-button>
           </div>
         </div>
       </div>
     </div>
-    <!-- 商品详情 -->
     <div class="base-width item-intro" ref="itemIntroGoods">
       <div>商品介绍</div>
       <div v-html="goodsSku.intro" class="mt_10 ml_10" v-if="goodsSku.intro"></div>
@@ -86,101 +94,140 @@
 
 <script>
 import { Message } from "@/utils/message";
-import Search from '@/components/Search';
-import { addCartGoods } from '@/api/cart.js';
-import { pointGoodsDetail } from '@/api/promotion';
+import Search from "@/components/Search";
+import { addCartGoods } from "@/api/cart.js";
+import { pointGoodsDetail } from "@/api/promotion";
+import {
+  isECoupon,
+  getECouponStock,
+  getECouponMaxBuyNum,
+  E_COUPON_CART_POINTS,
+} from "@/constants/goodsType";
+
 export default {
-  name: 'PointGoodsDetail',
-  beforeRouteEnter (to, from, next) {
+  name: "PointGoodsDetail",
+  components: { Search },
+  beforeRouteEnter(to, from, next) {
     window.scrollTo(0, 0);
     next();
   },
-  created () {
+  created() {
     this.getGoodsDetail();
   },
-  mounted () {
-    window.addEventListener('scroll', this.handleScroll)
+  mounted() {
+    window.addEventListener("scroll", this.handleScroll);
   },
-  data () {
+  data() {
     return {
-      goodsMsg: {}, // 商品信息
-      goodsSku: {}, // 商品sku
-      isLoading: false, // 加载状态
-      categoryBar: [], // 分类
-      onceFlag: true, // 只调用一次
-      count: 1, // 购买商品数量
-      loading: false // 提交加载状态
+      goodsMsg: {},
+      goodsSku: {},
+      isLoading: false,
+      onceFlag: true,
+      count: 1,
+      loading: false,
     };
   },
-  methods: {
-    // 获取积分商品详情
-    getGoodsDetail () {
-      this.isLoading = true;
-      pointGoodsDetail(this.$route.query.id).then((res) => {
-        this.isLoading = false;
-        if (res.success) {
-          this.goodsMsg = res.result;
-          this.goodsSku = res.result.goodsSku
-        } else {
-          Message.error(res.message)
-          this.$router.push('/')
-        }
-      }).catch(() => {
-        this.$router.push('/')
-      });
+  computed: {
+    isECouponSku() {
+      return isECoupon(this.goodsSku.goodsType);
     },
-    pointBuy () {
+    displayStock() {
+      if (this.isECouponSku) {
+        return getECouponStock(this.goodsSku);
+      }
+      return Number(this.goodsSku.quantity) || 0;
+    },
+    quantityMax() {
+      if (this.isECouponSku) {
+        return getECouponMaxBuyNum(this.goodsSku);
+      }
+      const qty = Number(this.goodsSku.quantity) || 0;
+      return qty > 0 ? qty : 1;
+    },
+    isOutOfStock() {
+      return this.displayStock <= 0;
+    },
+  },
+  methods: {
+    getGoodsDetail() {
+      this.isLoading = true;
+      pointGoodsDetail(this.$route.query.id)
+        .then((res) => {
+          this.isLoading = false;
+          if (res.success) {
+            this.goodsMsg = res.result;
+            this.goodsSku = res.result.goodsSku || {};
+            this.syncCountWithQuantity();
+          } else {
+            Message.error(res.message);
+            this.$router.push("/");
+          }
+        })
+        .catch(() => {
+          this.$router.push("/");
+        });
+    },
+    syncCountWithQuantity() {
+      const max = this.quantityMax;
+      if (max <= 0) {
+        this.count = 1;
+        return;
+      }
+      if (this.count > max) this.count = max;
+      if (this.count < 1) this.count = 1;
+    },
+    pointBuy() {
       const params = {
         num: this.count,
         skuId: this.goodsMsg.skuId,
-        cartType: 'POINTS'
+        cartType: E_COUPON_CART_POINTS,
       };
       this.loading = true;
-      addCartGoods(params).then(res => {
-        this.loading = false;
-        if (res.success) {
-          this.$router.push({path: '/pay', query: {way: params.cartType}});
-        } else {
-          Message.warning(res.message);
-        }
-      }).catch(() => {
-        this.loading = false;
-      });
+      addCartGoods(params)
+        .then((res) => {
+          this.loading = false;
+          if (res.success) {
+            this.$router.push({ path: "/pay", query: { way: params.cartType } });
+          } else {
+            Message.warning(res.message);
+          }
+        })
+        .catch(() => {
+          this.loading = false;
+        });
     },
-    handleScroll () { // 监听页面滚动
+    handleScroll() {
       if (this.onceFlag) {
         this.$nextTick(() => {
-          this.changeHeight()
+          this.changeHeight();
         });
-        this.onceFlag = false
+        this.onceFlag = false;
       }
     },
-    changeHeight () { // 设置商品详情高度
-      let goodsDetailCon = document.querySelector('.item-intro')
+    changeHeight() {
+      const goodsDetailCon = document.querySelector(".item-intro");
+      if (!goodsDetailCon || !this.$refs.itemIntroGoods) return;
       let heightCss = window.getComputedStyle(goodsDetailCon).height;
-      heightCss = parseInt(heightCss.substr(0, heightCss.length - 2)) + 89;
-      this.$refs.itemIntroGoods.style.height = heightCss + 'px';
-    }
+      heightCss = parseInt(heightCss.substr(0, heightCss.length - 2), 10) + 89;
+      this.$refs.itemIntroGoods.style.height = heightCss + "px";
+    },
   },
-  components: {
-    Search,
-  }
 };
 </script>
+
 <style scoped lang="scss">
-.base-width{
+.base-width {
   width: 1200px;
   margin: 0 auto;
   position: relative;
 }
-.cate-container{
+.cate-container {
   background-color: #eee;
   height: 30px;
   line-height: 30px;
   padding-left: 10px;
   margin-top: 10px;
 }
-// 商品图片，价格等
 .item-detail-show {
   width: 1200px;
   margin: 0 auto;
@@ -192,7 +239,6 @@ export default {
   width: 350px;
   margin-right: 30px;
 }
-
 .item-detail-big-img {
   width: 350px;
   height: 350px;
@@ -202,12 +248,10 @@ export default {
     width: 100%;
   }
 }
-
 .item-detail-img-row {
   margin-top: 15px;
   display: flex;
 }
-
 .item-detail-img-small {
   width: 68px;
   height: 68px;
@@ -219,20 +263,27 @@ export default {
     width: 100%;
   }
 }
-/*商品选购详情*/
 .item-detail-right {
   flex: 1;
   display: flex;
   flex-direction: column;
 }
-
+.item-detail-title-row {
+  display: flex;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: 8px;
+}
 .item-detail-title p {
   @include content_color($light_content_color);
   font-weight: bold;
   font-size: 20px;
   padding: 8px 0;
+  margin: 0;
+}
+.goods-type-tag {
+  flex-shrink: 0;
 }
-
 .item-detail-express {
   font-size: 14px;
   padding: 2px 3px;
@@ -240,15 +291,6 @@ export default {
   background-color: $theme_color;
   color: #fff;
 }
-
-/*商品标签*/
-.item-detail-tag {
-  padding: 8px 0;
-  font-size: 12px;
-  color: $theme_color;
-}
-
-/*价格详情等*/
 .item-detail-price-row {
   padding: 10px;
   display: flex;
@@ -256,42 +298,31 @@ export default {
   justify-content: space-between;
   background: url("../../assets/images/goodsDetail/price-bg.png");
 }
-
 .item-price-left {
   display: flex;
   flex-direction: column;
 }
-
 .item-price-title {
   color: #999999;
   font-size: 14px;
   margin-right: 15px;
 }
-
 .item-price-row {
   margin: 5px 0px;
 }
-
 .item-price {
   color: $theme_color;
   font-size: 20px;
   cursor: pointer;
 }
-.item-price-old {
-  color: gray;
-  text-decoration: line-through;
-  font-size: 14px;
-  margin-left: 5px;
-}
 .add-buy-car-box {
   width: 100%;
   margin-top: 15px;
   border-top: 1px dotted $border_color;
 }
-
 .add-buy-car {
   margin-top: 15px;
-  >*{
+  > * {
     margin: 0 4px;
   }
 }
@@ -300,57 +331,23 @@ export default {
   flex-direction: row;
   margin-top: 15px;
 }
-
 .item-select-title {
   @include content_color($light_content_color);
   font-size: 14px;
   margin-right: 15px;
   width: 60px;
 }
-
-.item-select-column {
-  display: flex;
-  flex-wrap: wrap;
-  flex: 1;
-}
-
 .item-select-row {
   margin-bottom: 8px;
 }
-
-.item-select-box {
-  display: flex;
-  flex-direction: row;
-  align-items: center;
-  padding: 5px;
-  margin-right: 8px;
-  @include background_color($light_background_color);
-  border: 0.5px solid $border_color;
-  cursor: pointer;
-  @include content_color($light_content_color);
-}
-
-.item-select-box:hover {
-  border: 0.5px solid $theme_color;
-}
-
-.item-select-box-active {
-  border: 0.5px solid $theme_color;
-}
-
-.item-select-intro p {
-  margin: 0px;
-  padding: 5px;
-}
 .sell-point {
   font-size: 12px;
   color: red;
   margin-bottom: 5px;
 }
-// 商品详情
 .item-intro {
   margin-top: 10px;
-  >div:nth-child(1) {
+  > div:nth-child(1) {
     height: 40px;
     line-height: 40px;
     background-color: #eee;