Handle the idle transition in the UI

web/packages/new/photos/services/ml/index.ts

@@ -89,7 +89,7 @@ const worker = () =>
 const createComlinkWorker = async () => {
     const electron = ensureElectron();
     const delegate = {
-        workerDidProcessFile,
+        workerDidProcessFileOrIdle,
     };
 
     // Obtain a message port from the Electron layer.
@@ -523,7 +523,7 @@ const setInterimScheduledStatus = () => {
     setMLStatusSnapshot({ phase: "scheduled", nSyncedFiles, nTotalFiles });
 };
 
-const workerDidProcessFile = throttled(updateMLStatusSnapshot, 2000);
+const workerDidProcessFileOrIdle = throttled(updateMLStatusSnapshot, 2000);
 
 /**
  * Use CLIP to perform a natural language search over image embeddings.

web/packages/new/photos/services/ml/worker-types.ts

@@ -8,11 +8,10 @@
  */
 export interface MLWorkerDelegate {
     /**
-     * Called whenever a file is processed during indexing.
-     *
-     * It is called both when the indexing was successful or it failed.
+     * Called whenever the worker processes a file during indexing (either
+     * successfully or with errors), or when in goes into the "idle" state.
      */
-    workerDidProcessFile: () => void;
+    workerDidProcessFileOrIdle: () => void;
 }
 
 /**

web/packages/new/photos/services/ml/worker.ts

@@ -233,6 +233,7 @@ export class MLWorker {
         this.state = "idle";
         this.idleDuration = Math.min(this.idleDuration * 2, idleDurationMax);
         this.idleTimeout = setTimeout(scheduleTick, this.idleDuration * 1000);
+        this.delegate?.workerDidProcessFileOrIdle();
     }
 
     /** Return the next batch of items to backfill (if any). */
@@ -320,7 +321,7 @@ const indexNextBatch = async (
         await Promise.race(tasks);
 
         // Let the main thread now we're doing something.
-        delegate?.workerDidProcessFile();
+        delegate?.workerDidProcessFileOrIdle();
 
         // Let us drain the microtask queue. This also gives a chance for other
         // interactive tasks like `clipMatches` to run.