wavesurfer lazy loading

electron-ui/src/renderer/components/AudioTrimer.tsx

@@ -44,6 +44,8 @@ export default function AudioTrimmer({
     useSortable({ id: metadata.filename });
 
   // Dialog state for editing name
+  const rootRef = useRef<HTMLDivElement | null>(null);
+  const [isVisible, setIsVisible] = useState(false);
   const [editDialogOpen, setEditDialogOpen] = useState(false);
   const [deleteDialogOpen, setDeleteDialogOpen] = useState(false);
   const [dropdownOpen, setDropdownOpen] = useState(false);
@@ -202,25 +204,40 @@ export default function AudioTrimmer({
   }, [onRegionCreated, onRegionUpdated, plugins]);
 
   useEffect(() => {
-    let url: string | null = null;
+    const node = rootRef.current;
+    if (!node) return;
+    const observer = new window.IntersectionObserver(
+      ([entry]) => {
+        if (entry.isIntersecting) {
+          setIsVisible(true);
+        }
+      },
+      { threshold: 0.1 },
+    );
+    observer.observe(node);
+    return () => {
+      observer.disconnect();
+    };
+  }, []);
+
+  useEffect(() => {
+    if (!isVisible) return;
+    let cancelled = false;
     async function fetchAudio() {
-      //   console.log('Loading audio buffer for file:', filename);
       const buffer = await window.audio.loadAudioBuffer(metadata.filename);
-      // console.log('Received buffer:', buffer.buffer);
+      if (cancelled) return;
       if (buffer.buffer && !buffer.error) {
         const audioData = buffer.buffer
           ? new Uint8Array(buffer.buffer)
           : buffer;
-        url = URL.createObjectURL(new Blob([audioData]));
+        wavesurfer?.loadBlob(new Blob([audioData]));
-        // console.log('Created blob URL:', url);
-        setBlobUrl(url);
       }
     }
     fetchAudio();
     return () => {
-      if (url) URL.revokeObjectURL(url);
+      cancelled = true;
     };
-  }, [metadata.filename]);
+  }, [isVisible, metadata.filename, wavesurfer]);
 
   const onPlayPause = () => {
     if (wavesurfer === null) return;
@@ -245,7 +262,10 @@ export default function AudioTrimmer({
 
   return (
     <div
-      ref={setNodeRef}
+      ref={(el) => {
+        setNodeRef(el);
+        rootRef.current = el;
+      }}
       style={{
         transform: CSS.Transform.toString(transform),
         transition,