From 364c99381c6649ff5afd6ea3ce9b1fd1a96e5dcb Mon Sep 17 00:00:00 2001
From: beo3000 <pakabu@web.de>
Date: Sat, 21 Feb 2026 19:44:03 +0100
Subject: [PATCH] fix: chunked base64 encode/decode for large image blobs in
 sync

---
 ka-note/VERSION                            |  2 +-
 ka-note/client/src/lib/sync/syncService.ts | 20 +++++++++++++-------
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/ka-note/VERSION b/ka-note/VERSION
index fd8b4f0..4686f75 100644
--- a/ka-note/VERSION
+++ b/ka-note/VERSION
@@ -1 +1 @@
-1.0.12
\ No newline at end of file
+1.0.13
\ No newline at end of file
diff --git a/ka-note/client/src/lib/sync/syncService.ts b/ka-note/client/src/lib/sync/syncService.ts
index 3d2c17b..b889994 100644
--- a/ka-note/client/src/lib/sync/syncService.ts
+++ b/ka-note/client/src/lib/sync/syncService.ts
@@ -41,9 +41,7 @@ async function pullAndMerge(since: Date | null): Promise<string> {
 	if (!res.ok) throw new Error(`Pull failed: ${res.status}`);
 	const data: SyncPullResponse = await res.json();
 
-	const { contexts, topics, historyEntries, ratings } = data.changes;
-
-	const { imageBlobs } = data.changes;
+	const { contexts, topics, historyEntries, ratings, imageBlobs } = data.changes;
 
 	await db.transaction('rw', [db.contexts, db.topics, db.historyEntries, db.ratings, db.imageBlobs], async () => {
 		for (const serverCtx of contexts) {
@@ -73,8 +71,10 @@ async function pullAndMerge(since: Date | null): Promise<string> {
 		for (const serverBlob of (imageBlobs ?? [])) {
 			const local = await db.imageBlobs.get(serverBlob.id);
 			if (!local || serverBlob.version > local.version) {
-				// Decode base64 → Blob
-				const bytes = Uint8Array.from(atob(serverBlob.data), (c) => c.charCodeAt(0));
+				// Decode base64 → Blob (chunked to avoid stack overflow on large blobs)
+				const binary = atob(serverBlob.data);
+				const bytes = new Uint8Array(binary.length);
+				for (let i = 0; i < binary.length; i++) bytes[i] = binary.charCodeAt(i);
 				const blobData = new Blob([bytes], { type: serverBlob.mimeType });
 				await db.imageBlobs.put({
 					id: serverBlob.id,
@@ -102,11 +102,17 @@ async function pushAll(): Promise<void> {
 		db.imageBlobs.toArray(),
 	]);
 
-	// Encode Blob → base64 for transport
+	// Encode Blob → base64 for transport (chunked to avoid stack overflow on large blobs)
 	const imageBlobs = await Promise.all(
 		localBlobs.map(async (b) => {
 			const buf = await b.data.arrayBuffer();
-			const base64 = btoa(String.fromCharCode(...new Uint8Array(buf)));
+			const bytes = new Uint8Array(buf);
+			let binary = '';
+			const CHUNK = 8192;
+			for (let i = 0; i < bytes.length; i += CHUNK) {
+				binary += String.fromCharCode(...bytes.subarray(i, i + CHUNK));
+			}
+			const base64 = btoa(binary);
 			return {
 				id: b.id,
 				mimeType: b.mimeType,