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/admin/user/withdrawalCommon.go

@@ -0,0 +1,98 @@
+package user
+
+import (
+	"context"
+	"strings"
+
+	logicCommon "github.com/perfect-panel/server/internal/logic/common"
+	"github.com/perfect-panel/server/internal/model/log"
+	usermodel "github.com/perfect-panel/server/internal/model/user"
+	"github.com/perfect-panel/server/internal/svc"
+	"github.com/perfect-panel/server/pkg/logger"
+	"github.com/perfect-panel/server/pkg/xerr"
+	"github.com/pkg/errors"
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
+)
+
+func approveWithdrawal(ctx context.Context, svcCtx *svc.ServiceContext, withdrawalID int64) error {
+	var approvedUserID int64
+	err := svcCtx.DB.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		withdrawal, err := logicCommon.LoadPendingWithdrawalForUpdate(ctx, tx, withdrawalID)
+		if err != nil {
+			if err.Error() == "withdrawal status invalid" {
+				return errors.Wrapf(xerr.NewErrCode(xerr.WithdrawalStatusInvalid), "withdrawal %d already processed", withdrawalID)
+			}
+			return errors.Wrapf(xerr.NewErrCode(xerr.DatabaseQueryError), "load withdrawal failed: %v", err)
+		}
+
+		// Lock user row and verify sufficient balance before deducting.
+		var u usermodel.User
+		if err := tx.Clauses(clause.Locking{Strength: "UPDATE"}).
+			Where("id = ?", withdrawal.UserId).First(&u).Error; err != nil {
+			return errors.Wrapf(xerr.NewErrCode(xerr.DatabaseQueryError), "load user failed: %v", err)
+		}
+		if u.Commission < withdrawal.Amount {
+			return errors.Wrapf(xerr.NewErrCode(xerr.UserCommissionNotEnough), "user %d has insufficient commission balance", withdrawal.UserId)
+		}
+
+		if err := tx.Model(&usermodel.Withdrawal{}).
+			Where("id = ? AND status = 0", withdrawalID).
+			Updates(map[string]interface{}{
+				"status": 1,
+				"reason": "",
+			}).Error; err != nil {
+			return errors.Wrapf(xerr.NewErrCode(xerr.DatabaseUpdateError), "approve withdrawal failed: %v", err)
+		}
+
+		// Deduct commission atomically inside the transaction.
+		if err := tx.Model(&usermodel.User{}).
+			Where("id = ?", withdrawal.UserId).
+			UpdateColumn("commission", gorm.Expr("commission - ?", withdrawal.Amount)).Error; err != nil {
+			return errors.Wrapf(xerr.NewErrCode(xerr.DatabaseUpdateError), "deduct commission failed: %v", err)
+		}
+
+		if err := logicCommon.WriteCommissionLog(tx, withdrawal.UserId, log.CommissionTypeWithdraw, withdrawal.Amount, ""); err != nil {
+			return errors.Wrapf(xerr.NewErrCode(xerr.DatabaseInsertError), "write commission log failed: %v", err)
+		}
+
+		approvedUserID = withdrawal.UserId
+		return nil
+	})
+
+	if err == nil && approvedUserID > 0 {
+		_ = svcCtx.UserModel.ClearUserCache(ctx, &usermodel.User{Id: approvedUserID})
+	}
+	return err
+}
+
+func rejectWithdrawal(ctx context.Context, svcCtx *svc.ServiceContext, withdrawalID int64, reason string) error {
+	reason = strings.TrimSpace(reason)
+	return svcCtx.DB.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		_, err := logicCommon.LoadPendingWithdrawalForUpdate(ctx, tx, withdrawalID)
+		if err != nil {
+			if err.Error() == "withdrawal status invalid" {
+				return errors.Wrapf(xerr.NewErrCode(xerr.WithdrawalStatusInvalid), "withdrawal %d already processed", withdrawalID)
+			}
+			return errors.Wrapf(xerr.NewErrCode(xerr.DatabaseQueryError), "load withdrawal failed: %v", err)
+		}
+
+		// Commission was NOT deducted at application time under the new logic,
+		// so rejection requires no refund — only a status update.
+		return tx.Model(&usermodel.Withdrawal{}).
+			Where("id = ? AND status = 0", withdrawalID).
+			Updates(map[string]interface{}{
+				"status": 2,
+				"reason": reason,
+			}).Error
+	})
+}
+
+func isWithdrawalScene(remark string) bool {
+	normalized := strings.ToLower(strings.TrimSpace(remark))
+	return strings.Contains(normalized, "withdraw") || strings.Contains(normalized, "提现")
+}
+
+func logWithdrawalGuard(l logger.Logger, userID int64) {
+	l.Errorw("blocked commission overwrite in withdrawal scene", logger.Field("user_id", userID))
+}

internal/logic/common/withdrawal.go

@@ -0,0 +1,48 @@
+package common
+
+import (
+	"context"
+	"time"
+
+	"github.com/perfect-panel/server/internal/model/log"
+	usermodel "github.com/perfect-panel/server/internal/model/user"
+	"github.com/pkg/errors"
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
+)
+
+func WriteCommissionLog(tx *gorm.DB, objectID int64, logType uint16, amount int64, orderNo string) error {
+	logInfo := log.Commission{
+		Type:      logType,
+		Amount:    amount,
+		OrderNo:   orderNo,
+		Timestamp: time.Now().UnixMilli(),
+	}
+
+	content, err := logInfo.Marshal()
+	if err != nil {
+		return err
+	}
+
+	return tx.Model(log.SystemLog{}).Create(&log.SystemLog{
+		Type:      log.TypeCommission.Uint8(),
+		Date:      time.Now().Format(time.DateOnly),
+		ObjectID:  objectID,
+		Content:   string(content),
+		CreatedAt: time.Now(),
+	}).Error
+}
+
+func LoadPendingWithdrawalForUpdate(ctx context.Context, tx *gorm.DB, withdrawalID int64) (*usermodel.Withdrawal, error) {
+	var withdrawal usermodel.Withdrawal
+	if err := tx.WithContext(ctx).
+		Clauses(clause.Locking{Strength: "UPDATE"}).
+		Where("id = ?", withdrawalID).
+		First(&withdrawal).Error; err != nil {
+		return nil, err
+	}
+	if withdrawal.Status != 0 {
+		return nil, errors.New("withdrawal status invalid")
+	}
+	return &withdrawal, nil
+}

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
 }