初始化

API/internal/billing/generation.go

@@ -0,0 +1,59 @@
+package billing
+
+import (
+	"errors"
+	"strconv"
+
+	"juhe-factory/api/internal/model"
+
+	"github.com/google/uuid"
+	"gorm.io/gorm"
+)
+
+// PrechargeGenerationTask creates a task and reserves its full quoted cost in
+// the same transaction. A zero price is allowed only when the model has an
+// explicit zero-price record; callers must reject a missing price record.
+func PrechargeGenerationTask(tx *gorm.DB, task *model.GenerationTask, unitPrice string, quantity int, remark string) error {
+	price, err := strconv.ParseFloat(unitPrice, 64)
+	if err != nil || price < 0 || quantity <= 0 {
+		return errors.New("生成任务价格无效")
+	}
+	var amount string
+	if err := tx.Raw("SELECT round(?::numeric * ?::numeric,2)::text", unitPrice, quantity).Scan(&amount).Error; err != nil {
+		return err
+	}
+	if amount == "" {
+		return errors.New("生成任务价格无效")
+	}
+	task.EstimatedPoints = amount
+	task.PrepaidPoints = amount
+	if task.ID == uuid.Nil {
+		task.ID = uuid.New()
+	}
+
+	if amountValue, _ := strconv.ParseFloat(amount, 64); amountValue > 0 {
+		if _, err := DebitPoints(tx, task.UserID, amount, "generation_hold", task.ID.String(), remark, "generation:hold:"+task.ID.String()); err != nil {
+			return err
+		}
+	}
+	if err := tx.Create(task).Error; err != nil {
+		return err
+	}
+	return nil
+}
+
+// RefundGenerationTask refunds a prepaid task exactly once. The caller must
+// hold a row lock on task inside the same transaction.
+func RefundGenerationTask(tx *gorm.DB, task *model.GenerationTask, remark string) (bool, error) {
+	amount, _ := strconv.ParseFloat(task.PrepaidPoints, 64)
+	if task.CostRefunded || amount <= 0 {
+		return false, nil
+	}
+	refunded, err := RefundDebit(tx, task.UserID, "generation:hold:"+task.ID.String(), "generation:refund:"+task.ID.String(),
+		"generation_refund", task.ID.String(), remark)
+	if err != nil {
+		return false, err
+	}
+	task.CostRefunded = true
+	return refunded, nil
+}