From a94d486a4243c67fe1cc6779d8f4bb89052b419e Mon Sep 17 00:00:00 2001
From: Matthias Hochmeister <matthias.hochmeister@apple.com>
Date: Tue, 14 Apr 2026 14:46:34 +0200
Subject: [PATCH] fix(buchhaltung): prevent form reset on query refetch during
 transaction edit

---
 frontend/src/pages/BuchhaltungTransaktionForm.tsx | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/frontend/src/pages/BuchhaltungTransaktionForm.tsx b/frontend/src/pages/BuchhaltungTransaktionForm.tsx
index 718c7a1..b6c044b 100644
--- a/frontend/src/pages/BuchhaltungTransaktionForm.tsx
+++ b/frontend/src/pages/BuchhaltungTransaktionForm.tsx
@@ -1,4 +1,4 @@
-import { useState, useEffect } from 'react';
+import { useState, useEffect, useRef } from 'react';
 import { useParams, useNavigate, useSearchParams } from 'react-router-dom';
 import { useQuery, useMutation } from '@tanstack/react-query';
 import {
@@ -74,9 +74,12 @@ export default function BuchhaltungTransaktionForm() {
   // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [haushaltsjahre]);
 
-  // Pre-fill from existing transaction when editing
+  const hasPrefilled = useRef(false);
+
+  // Pre-fill from existing transaction when editing — only once
   useEffect(() => {
-    if (existing) {
+    if (existing && !hasPrefilled.current) {
+      hasPrefilled.current = true;
       setForm({
         haushaltsjahr_id: existing.haushaltsjahr_id,
         typ: existing.typ as 'einnahme' | 'ausgabe',