Handle cleared MPV entry during fallback failure

web/backend/src/MediaPlayer.ts

@@ -539,7 +539,10 @@ export class MediaPlayer {
         if (result?.error !== "success") {
             if (fallbackEligible) {
                 this.removePendingCandidate(url);
-                if (![...this.entryCandidates.values()].includes(url)) this.fallbackCandidates.delete(url);
+                if (!this.pendingCandidateUrls.includes(url) &&
+                    ![...this.entryCandidates.values()].includes(url)) {
+                    this.fallbackCandidates.delete(url);
+                }
             }
             return;
         }
@@ -784,6 +787,13 @@ export class MediaPlayer {
         const file = this.entryCandidates.get(entryId) || response.file ||
             (entryId === this.activeEntryId ? this.activeUrl : null);
         if (!file) return;
+        if (this.activeEntryId === null && !this.fallbackSuppressedUntilStart) {
+            // MPV can clear its current entry before delivering end-file. Restore
+            // this event's known entry from its playlist_entry_id for mirroring.
+            this.activeEntryId = entryId;
+            this.activeUrl = file;
+            this.currentFile = file;
+        }
         const errorMessage = response.file_error || response.error || response["file-error"] || "Unknown playback error";
         this.playbackErrors.set(file, errorMessage);
         this.handleEvent(UserEvent.PlaybackError, { filename: file, error: errorMessage });

web/backend/test/MediaPlayerFallback.test.cjs

@@ -119,6 +119,9 @@ test("failure is correlated from MPV end-file entry id without querying a cleare
     assert.notEqual(command, "get_property", "failure correlation must use the emitted entry id");
     return { data: [] };
   };
+  player.activeEntryId = null;
+  player.activeUrl = null;
+  player.currentFile = null;
   send(player, { reason: "error", file_error: "network unavailable" }, 42);
   await settle();
   assert.deepEqual(starts, [url]);