新功能(#74): 新增促销系统模型层

Co-authored-by: multica-agent <github@multica.ai>

internal/model/promo_usage/model.go

@@ -0,0 +1,71 @@
+package promo_usage
+
+import (
+	"context"
+
+	"github.com/redis/go-redis/v9"
+	"gorm.io/gorm"
+)
+
+type customPromoUsageLogicModel interface {
+	FindByOrderNo(ctx context.Context, orderNo string) ([]*PromoUsage, error)
+	FindByUserAndRule(ctx context.Context, userId, promoRuleId int64) ([]*PromoUsage, error)
+	QueryListByPage(ctx context.Context, page, size int, userId, promoRuleId, subscribeId int64) (int64, []*PromoUsage, error)
+}
+
+func NewModel(conn *gorm.DB, c *redis.Client) Model {
+	return &customPromoUsageModel{
+		defaultPromoUsageModel: newPromoUsageModel(conn, c),
+	}
+}
+
+func (m *customPromoUsageModel) FindByOrderNo(ctx context.Context, orderNo string) ([]*PromoUsage, error) {
+	var list []*PromoUsage
+	err := m.QueryNoCacheCtx(ctx, &list, func(conn *gorm.DB, v interface{}) error {
+		return conn.Model(&PromoUsage{}).
+			Where("order_no = ?", orderNo).
+			Order("id DESC").
+			Find(v).Error
+	})
+	return list, err
+}
+
+func (m *customPromoUsageModel) FindByUserAndRule(ctx context.Context, userId, promoRuleId int64) ([]*PromoUsage, error) {
+	var list []*PromoUsage
+	err := m.QueryNoCacheCtx(ctx, &list, func(conn *gorm.DB, v interface{}) error {
+		return conn.Model(&PromoUsage{}).
+			Where("user_id = ? AND promo_rule_id = ?", userId, promoRuleId).
+			Order("id DESC").
+			Find(v).Error
+	})
+	return list, err
+}
+
+func (m *customPromoUsageModel) QueryListByPage(ctx context.Context, page, size int, userId, promoRuleId, subscribeId int64) (int64, []*PromoUsage, error) {
+	var list []*PromoUsage
+	var total int64
+	if page <= 0 {
+		page = 1
+	}
+	if size <= 0 {
+		size = 20
+	}
+
+	err := m.QueryNoCacheCtx(ctx, &list, func(conn *gorm.DB, v interface{}) error {
+		db := conn.Model(&PromoUsage{})
+		if userId > 0 {
+			db = db.Where("user_id = ?", userId)
+		}
+		if promoRuleId > 0 {
+			db = db.Where("promo_rule_id = ?", promoRuleId)
+		}
+		if subscribeId > 0 {
+			db = db.Where("subscribe_id = ?", subscribeId)
+		}
+		if err := db.Count(&total).Error; err != nil {
+			return err
+		}
+		return db.Order("id DESC").Limit(size).Offset((page - 1) * size).Find(v).Error
+	})
+	return total, list, err
+}