Queue bounded stream prewarm requests

server/server.js

@@ -67,6 +67,7 @@ import { ingest as collectVideoMetadata, syncListening, linkListening, startThum
 import { registerCatalogRoutes } from './recommendations.js';
 import QRCode from 'qrcode';
 import { createYtdlpPool } from './ytdlp-pool.js';
+import { createWarmQueue } from './warm-queue.js';
 import { dirname, join as pathJoin } from 'node:path';
 
 // A media proxy must not die because one client's stream hit an edge case
@@ -728,15 +729,20 @@ function pickFormat(formats, { formatId, wantAudio, wantHeight }) {
 // GET /api/streams/warm?v=<id> — fire-and-forget: resolve streams into
 // streamCache so the real /api/streams a moment later is instant. Bounded
 // so a scrolling user can't queue dozens of yt-dlp processes.
-const WARM_MAX = 2;
-let warmActive = 0;
+const streamWarmQueue = createWarmQueue({
+  concurrency: 2,
+  maxQueued: 8,
+  run: async (id) => {
+    try { if (await media.getReady(id)) return; } catch { /* fall through */ }
+    await resolveStreams(id);
+  },
+});
 app.get('/api/streams/warm', async (c) => {
   const id = (c.req.query('v') || '').trim();
   if (!/^[A-Za-z0-9_-]{11}$/.test(id)) return c.body(null, 204);
-  if (warmActive >= WARM_MAX) return c.body(null, 204);
-  try { if (await media.getReady(id)) return c.body(null, 204); } catch { /* fall through */ }
-  warmActive++;
-  resolveStreams(id).catch(() => {}).finally(() => { warmActive--; });
+  // Best effort: bounded queue preserves a small burst (e.g. the first three
+  // search cards) while limiting background extractor work.
+  streamWarmQueue.enqueue(id);
   return c.body(null, 204);
 });