feat: add subscription balance redemption toggle (#3071)

model/subscription.go

@@ -160,6 +160,8 @@ type SubscriptionPlan struct {
 	Enabled   bool `json:"enabled" gorm:"default:true"`
 	SortOrder int  `json:"sort_order" gorm:"type:int;default:0"`
 
+	AllowBalancePay *bool `json:"allow_balance_pay" gorm:"default:true"`
+
 	StripePriceId         string `json:"stripe_price_id" gorm:"type:varchar(128);default:''"`
 	CreemProductId        string `json:"creem_product_id" gorm:"type:varchar(128);default:''"`
 	WaffoPancakeProductId string `json:"waffo_pancake_product_id" gorm:"type:varchar(128);default:''"`
@@ -193,6 +195,12 @@ func (p *SubscriptionPlan) BeforeUpdate(tx *gorm.DB) error {
 	return nil
 }
 
+func (p *SubscriptionPlan) NormalizeDefaults() {
+	if p.AllowBalancePay == nil {
+		p.AllowBalancePay = common.GetPointer(true)
+	}
+}
+
 // Subscription order (payment -> webhook -> create UserSubscription)
 type SubscriptionOrder struct {
 	Id     int     `json:"id"`
@@ -360,6 +368,7 @@ func getSubscriptionPlanByIdTx(tx *gorm.DB, id int) (*SubscriptionPlan, error) {
 	key := subscriptionPlanCacheKey(id)
 	if key != "" {
 		if cached, found, err := getSubscriptionPlanCache().Get(key); err == nil && found {
+			cached.NormalizeDefaults()
 			return &cached, nil
 		}
 	}
@@ -371,6 +380,7 @@ func getSubscriptionPlanByIdTx(tx *gorm.DB, id int) (*SubscriptionPlan, error) {
 	if err := query.Where("id = ?", id).First(&plan).Error; err != nil {
 		return nil, err
 	}
+	plan.NormalizeDefaults()
 	_ = getSubscriptionPlanCache().SetWithTTL(key, plan, subscriptionPlanCacheTTL())
 	return &plan, nil
 }
@@ -701,6 +711,9 @@ func PurchaseSubscriptionWithBalance(userId int, planId int) error {
 		if plan.PriceAmount < 0 {
 			return errors.New("套餐价格不能为负数")
 		}
+		if plan.AllowBalancePay != nil && !*plan.AllowBalancePay {
+			return errors.New("该套餐不允许使用余额兑换")
+		}
 
 		requiredQuota, err := calcSubscriptionBalanceQuota(plan.PriceAmount)
 		if err != nil {