From af71fbf4180c390f1c3aa83199f4d2f12726188d Mon Sep 17 00:00:00 2001
From: seita-uc <c201552k@gmail.com>
Date: Wed, 13 Apr 2022 14:50:43 +0900
Subject: [PATCH] :watermelon: Add: check balance before withdraw token

---
 tokens/jobs.go | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/tokens/jobs.go b/tokens/jobs.go
index 2e42808f..e8c47cf7 100644
--- a/tokens/jobs.go
+++ b/tokens/jobs.go
@@ -3,8 +3,10 @@ package tokens
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 
 	"github.com/flow-hydraulics/flow-wallet-api/jobs"
+	log "github.com/sirupsen/logrus"
 )
 
 const WithdrawalCreateJobType = "withdrawal_create"
@@ -26,6 +28,28 @@ func (s *ServiceImpl) executeCreateWithdrawalJob(ctx context.Context, j *jobs.Jo
 		return err
 	}
 
+	// check recipient nft balance if executed more than once
+	if j.ExecCount > 1 && attrs.Request.NftID != 0 {
+		detail, err := s.Details(ctx, attrs.Request.TokenName, attrs.Request.Recipient)
+		if err != nil {
+			return fmt.Errorf("failed to get nft balance: %w", err)
+		}
+		val := detail.Balance.CadenceValue.ToGoValue()
+		balances, ok := val.([]interface{})
+		if ok {
+			for i := range balances {
+				nftID, ok := balances[i].(uint64)
+				if !ok {
+					continue
+				}
+				if nftID == attrs.Request.NftID {
+					log.Warn("recipient already has token", attrs.Request.TokenName, nftID)
+					return nil
+				}
+			}
+		}
+	}
+
 	transaction, err := s.createWithdrawal(ctx, attrs.Sender, attrs.Request)
 	if err != nil {
 		return err