From 7e0b7f652a9c50afa14399ec69171c2f1e10028b Mon Sep 17 00:00:00 2001
From: 10k11 <339974264+10k11@users.noreply.github.com>
Date: Sun, 8 Nov 2026 15:57:38 +0530
Subject: [PATCH] desktop: open the window even when offline; fetch yt-dlp in
 the background

The first launch awaited the yt-dlp download and quit on failure, so the
app never showed a window without internet (for example in the AppImage
catalog test, which runs with --net=none).

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
---
 desktop/README.md |  2 +-
 desktop/ytdlp.mjs | 18 +++++++++++++-----
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/desktop/README.md b/desktop/README.md
index 649c490..95fd823 100644
--- a/desktop/README.md
+++ b/desktop/README.md
@@ -2,7 +2,7 @@
 
 An Electron wrapper that runs the regular Flux server on `127.0.0.1` and shows it in a window. No Node, Docker or setup needed for users. The server code is unchanged; the app only sets environment variables (`FLUX_LOCAL_MODE=1`, data in the OS app-data folder).
 
-- The **media engine** is downloaded (checksum-verified) on first launch into the app-data folder and self-updates on later launches.
+- The **media engine** is downloaded (checksum-verified) in the background on first launch into the app-data folder and self-updates on later launches. The app opens even when offline; downloads start working once the engine has arrived.
 - **FFmpeg / FFprobe** are bundled through `ffmpeg-static` and `ffprobe-static`.
 - **Local mode** (`FLUX_LOCAL_MODE=1`) treats the person running the app as signed in, so full-length downloads work without Google sign-in. It is ignored unless the server listens on `127.0.0.1`.
 
diff --git a/desktop/ytdlp.mjs b/desktop/ytdlp.mjs
index d755aa3..2422efa 100644
--- a/desktop/ytdlp.mjs
+++ b/desktop/ytdlp.mjs
@@ -1,6 +1,6 @@
 // Keeps a standalone yt-dlp in the app's data folder: downloaded and verified on
 // first launch, then self-updated in the background (sites change often).
-import { mkdir, writeFile, chmod, access } from "node:fs/promises";
+import { mkdir, writeFile, chmod, access, rename } from "node:fs/promises";
 import { createHash } from "node:crypto";
 import { spawn } from "node:child_process";
 import path from "node:path";
@@ -59,11 +59,17 @@ async function download(target) {
     createHash("sha256").update(bytes).digest("hex") !== expected.toLowerCase()
   )
     throw new Error("Checksum verification failed for yt-dlp.");
-  await writeFile(target, bytes);
-  if (process.platform !== "win32") await chmod(target, 0o755);
+  // Write to a temp name first so an interrupted download is never mistaken for a working binary.
+  const tmp = `${target}.part`;
+  await writeFile(tmp, bytes);
+  if (process.platform !== "win32") await chmod(tmp, 0o755);
+  await rename(tmp, target);
 }
 
-/** Returns the path to yt-dlp, downloading it on first run. Updates run in the background. */
+/**
+ * Returns the path to yt-dlp right away. On first run the download happens in the background,
+ * so the app still opens when offline; downloads work once yt-dlp has arrived.
+ */
 export async function ensureYtDlp(binDir) {
   await mkdir(binDir, { recursive: true });
   const target = path.join(
@@ -75,7 +81,9 @@ export async function ensureYtDlp(binDir) {
     () => false,
   );
   if (!exists) {
-    await download(target);
+    download(target).catch((error) =>
+      console.error(`Could not fetch yt-dlp yet: ${error.message}`),
+    );
     return target;
   }
   // Best effort: the standalone binary can update itself in place.