Merge: make transcript payload authoritative

Author: github-actions

index.html

@@ -61,7 +61,15 @@ <h2>Caption Listener Status</h2>
       async function check() {
         try {
           const res = await fetch(url, { cache: 'no-store' });
-          render(res.ok);
+          if (!res.ok) { render(false); return; }
+          const data = await res.json().catch(() => null);
+          // Prefer an explicit flag; otherwise check generated timestamp recency
+          if (data && data.active === true) { render(true); return; }
+          if (data && data.generated) {
+            const t = Date.parse(data.generated);
+            if (!Number.isNaN(t) && (Date.now() - t) < 5000) { render(true); return; }
+          }
+          render(false);
         } catch {
           render(false);
         }

scripts/run-whisper.js

@@ -123,7 +123,7 @@ async function main() {
 
   let transcript = '';
   const writeOut = debounce(() => {
-    const payload = { text: transcript.trim(), updatedAt: new Date().toISOString() };
+    const payload = { active: true, generated: new Date().toISOString(), text: transcript.trim() };
     try {
       fs.writeFileSync(outFile, JSON.stringify(payload, null, 2));
     } catch (e) {
@@ -155,14 +155,25 @@ async function main() {
 
   const shutdown = () => {
     try { child.kill('SIGINT'); } catch {}
-    writeOut();
+    // write a final 'inactive' payload so UIs know listener stopped
+    try {
+      const final = { active: false, generated: new Date().toISOString(), text: transcript.trim() };
+      fs.writeFileSync(outFile, JSON.stringify(final, null, 2));
+    } catch (e) {
+      // ignore
+    }
     setTimeout(() => process.exit(0), 250);
   };
   process.on('SIGINT', shutdown);
   process.on('SIGTERM', shutdown);
 
   child.on('exit', (code) => {
-    writeOut();
+    try {
+      const final = { active: false, generated: new Date().toISOString(), text: transcript.trim() };
+      fs.writeFileSync(outFile, JSON.stringify(final, null, 2));
+    } catch (e) {
+      // ignore
+    }
     console.log(`\n[run-whisper] whisper-stream exited with code ${code}`);
     process.exit(code || 0);
   });

scripts/whisper-transcript-watch.js

@@ -35,14 +35,15 @@ function toJsonPayload(srcPath, content) {
   if (ext === '.json') {
     try {
       const obj = JSON.parse(content);
-      if (typeof obj === 'string') return { text: obj, updatedAt: new Date().toISOString() };
-      if (obj && typeof obj.text === 'string') return { text: obj.text, updatedAt: new Date().toISOString() };
-      return { text: JSON.stringify(obj), updatedAt: new Date().toISOString() };
+      if (typeof obj === 'string') return { active: true, generated: new Date().toISOString(), text: obj };
+      if (obj && typeof obj.text === 'string') return { active: true, generated: new Date().toISOString(), text: obj.text };
+      // If already an object, try to preserve structure but still include active/generation
+      return { active: true, generated: new Date().toISOString(), text: typeof obj === 'object' ? JSON.stringify(obj) : String(obj) };
     } catch {
       // fall through to txt
     }
   }
-  return { text: content, updatedAt: new Date().toISOString() };
+  return { active: true, generated: new Date().toISOString(), text: content };
 }
 
 function writeOut(dst, payload) {

slides/captions-button.js

@@ -281,24 +281,33 @@
     try {
       const res = await fetch('whisper-demo/transcript.json', { cache: 'no-store' });
       if (res.ok) {
-        // Check if file was recently modified (within last 10 seconds)
-        const lastModified = res.headers.get('Last-Modified');
+        const data = await res.json().catch(() => null);
         let isActive = false;
-        
-        if (lastModified) {
-          const modifiedDate = new Date(lastModified);
-          const now = new Date();
-          const secondsSinceUpdate = (now - modifiedDate) / 1000;
-          isActive = secondsSinceUpdate < 10; // File updated in last 10 seconds
-          console.log('[Captions] Fetch successful - Age:', Math.round(secondsSinceUpdate), 's | Active:', isActive);
+
+        // Prefer an explicit active flag from the producer
+        if (data && data.active === true) {
+          isActive = true;
+        } else if (data && data.generated) {
+          const t = Date.parse(data.generated);
+          if (!Number.isNaN(t)) {
+            const secondsSince = (Date.now() - t) / 1000;
+            isActive = secondsSince < 10; // recent within 10s
+            console.log('[Captions] Data generated age:', Math.round(secondsSince), 's | Active:', isActive);
+          }
+        } else {
+          // Fallback: last-modified header as a hint
+          const lastModified = res.headers.get('Last-Modified');
+          if (lastModified) {
+            const modifiedDate = new Date(lastModified);
+            const secondsSinceUpdate = (Date.now() - modifiedDate) / 1000;
+            isActive = secondsSinceUpdate < 10;
+            console.log('[Captions] Last-Modified age hint:', Math.round(secondsSinceUpdate), 's | Active:', isActive);
+          }
         }
-        
-        const data = await res.json();
-        console.log('[Captions] Data received, length:', data.text?.length || 0);
-        // Button shows active status based on file modification time
+
+        console.log('[Captions] Data received, text length:', data?.text?.length || 0);
         updateCaptionButton(isActive);
-        // But always show the latest transcript text (even if slightly old)
-        updateLiveTranscript(data.text);
+        updateLiveTranscript(data?.text || '');
       } else {
         console.log('[Captions] Fetch failed:', res.status);
         updateCaptionButton(false);

whisper-demo/transcript.json

@@ -1,4 +1,6 @@
 {
-  "transcript": [],
-  "generated": "placeholder for CI link-checks"
+  "active": false,
+  "generated": "2026-02-13T00:00:00Z",
+  "text": "",
+  "note": "placeholder for CI link-checks"
 }