feat(backend): 授权订单列表接口——分页/筛选/汇总，支撑订单管理 tab

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

backend/internal/service/pay.go

@@ -40,6 +40,7 @@ var (
 	ErrPayAmount        = errors.New("回调金额与订单不符")
 	ErrPurchaseNotFound = errors.New("购买记录不存在")
 	ErrPromoUsed        = errors.New("首月特惠每个门店限购一次，本店已享受过")
+	ErrInvalidStatus    = errors.New("无效的订单状态")
 )
 
 // PromoBizCode 新店首月特惠（¥1/30 天标准版），每个门店仅可购买一次。
@@ -657,3 +658,140 @@ func (s *PayService) cancelOrder(orderNo string) (bool, error) {
 	}
 	return r.Data.Canceled, nil
 }
+
+// ---------- ⑥ 订单列表（授权管理·订单管理 tab 数据源）----------
+
+// PurchaseListItem 订单管理 tab 一行。pay_url 仅 pending 单输出（继续支付用），
+// paid/failed 抹空；amount 是 Deprecated 兼容串（同 formatMinor 口径）。
+type PurchaseListItem struct {
+	OutTradeNo  string     `json:"out_trade_no"`
+	BizCode     string     `json:"product_biz_code"`
+	AmountMinor int64      `json:"amount_minor"`
+	Currency    string     `json:"currency"`
+	Amount      string     `json:"amount"` // Deprecated: formatMinor(AmountMinor) 分转元字符串
+	Status      string     `json:"status"`
+	PayURL      string     `json:"pay_url"`
+	UserName    string     `json:"user_name"` // 下单人显示名（LEFT JOIN users.real_name），查不到留空
+	CreatedAt   time.Time  `json:"created_at"`
+	PaidAt      *time.Time `json:"paid_at"`
+	RenewedTo   *time.Time `json:"renewed_to"`
+}
+
+// PurchaseSummary 汇总统计：同店全量（不受分页/status 筛选影响）。
+type PurchaseSummary struct {
+	PaidTotalMinor int64 `json:"paid_total_minor"`
+	PaidCount      int64 `json:"paid_count"`
+	PendingCount   int64 `json:"pending_count"`
+	TotalCount     int64 `json:"total_count"`
+}
+
+// PurchaseList ListPurchases 响应体。
+type PurchaseList struct {
+	Items   []PurchaseListItem `json:"items"`
+	Total   int64              `json:"total"`
+	Summary PurchaseSummary    `json:"summary"`
+}
+
+// ListPurchases 本店订单列表：分页 + status 筛选 + 全量汇总。status 空=全部，
+// 非空须为 pending/paid/failed 之一（否则 ErrInvalidStatus，handler 回 400）。
+func (s *PayService) ListPurchases(shopID uint64, page, pageSize int, status string) (*PurchaseList, error) {
+	if status != "" && status != "pending" && status != "paid" && status != "failed" {
+		return nil, ErrInvalidStatus
+	}
+	if page < 1 {
+		page = 1
+	}
+	if pageSize < 1 {
+		pageSize = 20
+	}
+
+	// 每次从 s.db 重新起 query，避免 *gorm.DB 复用累加条件的坑。
+	scope := func() *gorm.DB {
+		q := s.db.Model(&model.LicensePurchase{}).Where("shop_id = ?", shopID)
+		if status != "" {
+			q = q.Where("status = ?", status)
+		}
+		return q
+	}
+
+	var total int64
+	if err := scope().Count(&total).Error; err != nil {
+		return nil, err
+	}
+
+	var rows []model.LicensePurchase
+	if err := scope().Order("created_at DESC, id DESC").
+		Offset((page - 1) * pageSize).Limit(pageSize).Find(&rows).Error; err != nil {
+		return nil, err
+	}
+
+	// 下单人显示名：批量查 users，查不到留空。
+	userIDs := make([]uint64, 0, len(rows))
+	seen := map[uint64]bool{}
+	for _, p := range rows {
+		if !seen[p.UserID] {
+			seen[p.UserID] = true
+			userIDs = append(userIDs, p.UserID)
+		}
+	}
+	names := map[uint64]string{}
+	if len(userIDs) > 0 {
+		var users []model.User
+		if err := s.db.Where("id IN ?", userIDs).Find(&users).Error; err != nil {
+			return nil, err
+		}
+		for _, u := range users {
+			names[u.ID] = u.RealName
+		}
+	}
+
+	items := make([]PurchaseListItem, 0, len(rows))
+	for _, p := range rows {
+		amount := formatMinor(p.AmountMinor)
+		if amount == "" {
+			amount = p.Amount
+		}
+		payURL := ""
+		if p.Status == "pending" {
+			payURL = p.PayURL
+		}
+		items = append(items, PurchaseListItem{
+			OutTradeNo:  p.OutTradeNo,
+			BizCode:     p.ProductBizCode,
+			AmountMinor: p.AmountMinor,
+			Currency:    p.Currency,
+			Amount:      amount,
+			Status:      p.Status,
+			PayURL:      payURL,
+			UserName:    names[p.UserID],
+			CreatedAt:   p.CreatedAt,
+			PaidAt:      p.PaidAt,
+			RenewedTo:   p.RenewedTo,
+		})
+	}
+
+	// 汇总：同店全量，一次 GROUP BY 扫出后内存汇总，不受分页/status 筛选影响。
+	var groups []struct {
+		Status string
+		Cnt    int64
+		Amt    int64
+	}
+	if err := s.db.Model(&model.LicensePurchase{}).
+		Select("status, COUNT(*) as cnt, COALESCE(SUM(amount_minor),0) as amt").
+		Where("shop_id = ?", shopID).Group("status").Scan(&groups).Error; err != nil {
+		return nil, err
+	}
+	summary := PurchaseSummary{}
+	for _, g := range groups {
+		summary.TotalCount += g.Cnt
+		switch g.Status {
+		case "paid":
+			summary.PaidCount = g.Cnt
+			summary.PaidTotalMinor = g.Amt
+		case "pending":
+			summary.PendingCount = g.Cnt
+		}
+	}
+
+	return &PurchaseList{Items: items, Total: total, Summary: summary}, nil
+}