fix: move withdrawal commission deduction from application to approval

- commissionWithdrawLogic: remove upfront commission deduction;
  balance check now includes sum of all pending withdrawals to prevent
  double-spending; transaction only creates the withdrawal record (status=0)
- approveWithdrawal: add FOR UPDATE lock on user row, balance check before
  deducting, atomic commission decrement and commission log inside one
  transaction; clear user cache after commit
- rejectWithdrawal: remove commission refund and log — commission was never
  deducted on application under the new flow
- add migration 02150: refund commission for existing status=0 withdrawals
  that were deducted under the old logic; includes rollback script

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

internal/logic/public/user/commissionWithdrawLogic.go

@@ -2,9 +2,7 @@ package user
 
 import (
 	"context"
-	"time"
 
-	"github.com/perfect-panel/server/internal/model/log"
 	"github.com/perfect-panel/server/internal/model/user"
 	"github.com/perfect-panel/server/internal/svc"
 	"github.com/perfect-panel/server/internal/types"
@@ -12,6 +10,7 @@ import (
 	"github.com/perfect-panel/server/pkg/logger"
 	"github.com/perfect-panel/server/pkg/xerr"
 	"github.com/pkg/errors"
+	"gorm.io/gorm"
 )
 
 type CommissionWithdrawLogic struct {
@@ -36,65 +35,38 @@ func (l *CommissionWithdrawLogic) CommissionWithdraw(req *types.CommissionWithdr
 		return nil, errors.Wrapf(xerr.NewErrCode(xerr.InvalidAccess), "Invalid Access")
 	}
 
-	if u.Commission < req.Amount {
-		logger.Errorf("User %d has insufficient commission balance: %.2f, requested: %.2f", u.Id, float64(u.Commission)/100, float64(req.Amount)/100)
+	// Sum all pending (status=0) withdrawals to compute available balance.
+	// Available = commission - pendingTotal; commission is only deducted on approval.
+	var pendingTotal int64
+	if err = l.svcCtx.DB.WithContext(l.ctx).
+		Model(&user.Withdrawal{}).
+		Where("user_id = ? AND status = 0", u.Id).
+		Select("COALESCE(SUM(amount), 0)").
+		Scan(&pendingTotal).Error; err != nil {
+		l.Errorf("Failed to query pending withdrawals for user %d: %v", u.Id, err)
+		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DatabaseQueryError), "Failed to query pending withdrawals for user %d", u.Id)
+	}
+
+	if u.Commission < req.Amount+pendingTotal {
+		logger.Errorf("User %d insufficient available commission: total=%d pending=%d requested=%d",
+			u.Id, u.Commission, pendingTotal, req.Amount)
 		return nil, errors.Wrapf(xerr.NewErrCode(xerr.UserCommissionNotEnough), "User %d has insufficient commission balance", u.Id)
 	}
 
-	tx := l.svcCtx.DB.WithContext(l.ctx).Begin()
-
-	// update user commission balance
-	u.Commission -= req.Amount
-	if err = l.svcCtx.UserModel.Update(l.ctx, u, tx); err != nil {
-		tx.Rollback()
-		l.Errorf("Failed to update user %d commission balance: %v", u.Id, err)
-		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DatabaseUpdateError), "Failed to update user %d commission balance: %v", u.Id, err)
-	}
-
-	// create withdrawal log
-	logInfo := log.Commission{
-		Type:      log.CommissionTypeConvertBalance,
-		Amount:    req.Amount,
-		Timestamp: time.Now().UnixMilli(),
-	}
-	b, err := logInfo.Marshal()
-
+	var w user.Withdrawal
+	err = l.svcCtx.DB.WithContext(l.ctx).Transaction(func(tx *gorm.DB) error {
+		w = user.Withdrawal{
+			UserId:  u.Id,
+			Amount:  req.Amount,
+			Content: req.Content,
+			Status:  0,
+			Reason:  "",
+		}
+		return tx.Create(&w).Error
+	})
 	if err != nil {
-		tx.Rollback()
-		l.Errorf("Failed to marshal commission log for user %d: %v", u.Id, err)
-		return nil, errors.Wrapf(xerr.NewErrCode(xerr.ERROR), "Failed to marshal commission log for user %d: %v", u.Id, err)
-	}
-
-	err = tx.Model(log.SystemLog{}).Create(&log.SystemLog{
-		Type:      log.TypeCommission.Uint8(),
-		Date:      time.Now().Format("2006-01-02"),
-		ObjectID:  u.Id,
-		Content:   string(b),
-		CreatedAt: time.Now(),
-	}).Error
-
-	if err != nil {
-		tx.Rollback()
-		l.Errorf("Failed to create commission log for user %d: %v", u.Id, err)
-		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DatabaseInsertError), "Failed to create commission log for user %d: %v", u.Id, err)
-	}
-
-	err = tx.Model(&user.Withdrawal{}).Create(&user.Withdrawal{
-		UserId:  u.Id,
-		Amount:  req.Amount,
-		Content: req.Content,
-		Status:  0,
-		Reason:  "",
-	}).Error
-
-	if err != nil {
-		tx.Rollback()
-		l.Errorf("Failed to create withdrawal log for user %d: %v", u.Id, err)
-		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DatabaseInsertError), "Failed to create withdrawal log for user %d: %v", u.Id, err)
-	}
-	if err = tx.Commit().Error; err != nil {
-		l.Errorf("Transaction commit failed for user %d withdrawal: %v", u.Id, err)
-		return nil, errors.Wrapf(xerr.NewErrCode(xerr.ERROR), "Transaction commit failed for user %d withdrawal: %v", u.Id, err)
+		l.Errorf("Failed to create withdrawal for user %d: %v", u.Id, err)
+		return nil, errors.Wrapf(xerr.NewErrCode(xerr.DatabaseInsertError), "Failed to create withdrawal for user %d: %v", u.Id, err)
 	}
 
 	return &types.WithdrawalLog{
@@ -103,6 +75,7 @@ func (l *CommissionWithdrawLogic) CommissionWithdraw(req *types.CommissionWithdr
 		Content:   req.Content,
 		Status:    0,
 		Reason:    "",
-		CreatedAt: time.Now().UnixMilli(),
+		CreatedAt: w.CreatedAt.UnixMilli(),
+		UpdatedAt: w.UpdatedAt.UnixMilli(),
 	}, nil
 }