feat(ticket): 添加水票可用数量计算和订单取消后水票回退功能

- 引入 getGltUserTicket 和 updateGltUserTicket API 接口
- 实现 getTicketAvailableQty 函数用于计算水票可用数量
- 添加 rollbackUserTicketAfterOrderCancel 函数处理订单取消后的水票回退逻辑
- 在订单取消时获取取消前的水票状态并进行数量对比
- 订单取消成功后自动回退相应的水票数量
- 添加水票回退失败时的错误提示和用户通知
- 更新取消订单的成功提示信息为"订单已取消，水票已退回"

src/user/ticket/index.tsx

@@ -14,7 +14,7 @@ import {
   Tag
 } from '@nutui/nutui-react-taro';
 import { View, Text, Image } from '@tarojs/components';
-import { pageGltUserTicket } from '@/api/glt/gltUserTicket';
+import { getGltUserTicket, pageGltUserTicket, updateGltUserTicket } from '@/api/glt/gltUserTicket';
 import type { GltUserTicket } from '@/api/glt/gltUserTicket/model';
 import { pageGltTicketOrder, removeGltTicketOrder, updateGltTicketOrder } from '@/api/glt/gltTicketOrder';
 import type { GltTicketOrder } from '@/api/glt/gltTicketOrder/model';
@@ -261,6 +261,65 @@ const UserTicketList = () => {
     return d.isValid() ? d.format('YYYY年MM月DD日') : v;
   };
 
+  const getTicketAvailableQty = (t?: Partial<GltUserTicket> | null) => {
+    if (!t) return 0;
+    const anyT: any = t;
+    const raw =
+      anyT.availableQty ??
+      anyT.availableNum ??
+      anyT.availableCount ??
+      anyT.remainQty ??
+      anyT.remainNum ??
+      anyT.remainCount;
+    const n = Number(raw);
+    if (Number.isFinite(n)) return n;
+
+    const total = Number(anyT.totalQty ?? anyT.totalNum ?? anyT.totalCount ?? 0);
+    const used = Number(anyT.usedQty ?? anyT.usedNum ?? anyT.usedCount ?? 0);
+    const frozen = Number(anyT.frozenQty ?? anyT.frozenNum ?? anyT.frozenCount ?? 0);
+    const computed =
+      (Number.isFinite(total) ? total : 0) -
+      (Number.isFinite(used) ? used : 0) -
+      (Number.isFinite(frozen) ? frozen : 0);
+    return Number.isFinite(computed) ? computed : 0;
+  };
+
+  const rollbackUserTicketAfterOrderCancel = async (order: GltTicketOrder, before?: GltUserTicket | null) => {
+    const ticketId = Number(order?.userTicketId);
+    const qty = Math.max(0, Math.floor(Number((order as any)?.totalNum ?? 0)));
+    if (!Number.isFinite(ticketId) || ticketId <= 0) return;
+    if (!Number.isFinite(qty) || qty <= 0) return;
+
+    const after = await getGltUserTicket(ticketId);
+    if (!after?.id) return;
+
+    const beforeAvail = before ? getTicketAvailableQty(before) : undefined;
+    const afterAvail = getTicketAvailableQty(after);
+
+    let need = qty;
+    if (typeof beforeAvail === 'number') {
+      const delta = afterAvail - beforeAvail;
+      if (delta >= qty) return; // backend already rolled back
+      if (delta > 0) need = Math.max(0, qty - delta);
+    }
+    if (need <= 0) return;
+
+    const currentAvailRaw = Number((after as any)?.availableQty);
+    const baseAvail = Number.isFinite(currentAvailRaw) ? currentAvailRaw : afterAvail;
+    const nextAvail = (Number.isFinite(baseAvail) ? baseAvail : 0) + need;
+
+    const frozenRaw = Number((after as any)?.frozenQty ?? 0);
+    const frozen = Number.isFinite(frozenRaw) ? frozenRaw : 0;
+    const reduceFrozen = Math.min(frozen, need);
+    const nextFrozen = reduceFrozen > 0 ? Math.max(0, frozen - reduceFrozen) : undefined;
+
+    await updateGltUserTicket({
+      ...after,
+      availableQty: nextAvail,
+      ...(nextFrozen !== undefined ? { frozenQty: nextFrozen } : {})
+    });
+  };
+
   // Allow users to modify/cancel before delivery starts (e.g. 待派单 / 待配送).
   const isTicketOrderPendingDelivery = (order: GltTicketOrder) => {
     if (!order?.id) return false;
@@ -306,12 +365,26 @@ const UserTicketList = () => {
 
     try {
       Taro.showLoading({ title: '取消中...' });
+      let beforeTicket: GltUserTicket | null = null;
+      if (order.userTicketId) {
+        beforeTicket = await getGltUserTicket(Number(order.userTicketId)).catch(() => null);
+      }
       try {
         await updateGltTicketOrder({ id: order.id, deleted: 1 });
       } catch (e) {
         await removeGltTicketOrder(order.id);
       }
-      Taro.showToast({ title: '订单已取消', icon: 'success' });
+      try {
+        await rollbackUserTicketAfterOrderCancel(order, beforeTicket);
+        Taro.showToast({ title: '订单已取消，水票已退回', icon: 'success' });
+      } catch (e) {
+        console.error('取消订单后退回水票失败:', e);
+        await Taro.showModal({
+          title: '取消成功',
+          content: '订单已取消，但水票退回失败，请稍后刷新“我的水票”确认，或联系客服处理。',
+          showCancel: false
+        });
+      }
       await reloadOrders(true);
     } catch (e) {
       console.error('取消送水订单失败:', e);