Sync subtitle and audio indexes between server and offline

hooks/useDownloadedFileOpener.ts

@@ -1,6 +1,7 @@
 import type { BaseItemDto } from "@jellyfin/sdk/lib/generated-client";
 import { useCallback } from "react";
 import useRouter from "@/hooks/useAppRouter";
+import { getDownloadedItemById } from "@/providers/Downloads/database";
 import { usePlaySettings } from "@/providers/PlaySettingsProvider";
 import { writeToLog } from "@/utils/log";
 
@@ -15,9 +16,14 @@ export const useDownloadedFileOpener = () => {
         console.error("Attempted to open a file without an ID.");
         return;
       }
+      const downloadedItem = getDownloadedItemById(item.Id);
       const queryParams = new URLSearchParams({
         itemId: item.Id,
         offline: "true",
+        audioIndex:
+          downloadedItem?.userData?.audioStreamIndex?.toString() ?? "",
+        subtitleIndex:
+          downloadedItem?.userData?.subtitleStreamIndex?.toString() ?? "-1",
         playbackPosition:
           item.UserData?.PlaybackPositionTicks?.toString() ?? "0",
       });

hooks/usePlaybackManager.ts

@@ -186,6 +186,20 @@ export const usePlaybackManager = ({
                 : playedPercentage,
           },
         },
+        // Sync selected audio/subtitle tracks so next playback resumes with
+        // the same tracks the user had active — but only for non-transcoded
+        // downloads where the user can freely switch tracks.
+        userData: localItem.userData.isTranscoded
+          ? localItem.userData
+          : {
+              ...localItem.userData,
+              ...(playbackProgressInfo.AudioStreamIndex != null && {
+                audioStreamIndex: playbackProgressInfo.AudioStreamIndex,
+              }),
+              ...(playbackProgressInfo.SubtitleStreamIndex != null && {
+                subtitleStreamIndex: playbackProgressInfo.SubtitleStreamIndex,
+              }),
+            },
       });
       // Force invalidate queries so they refetch from updated local database
       queryClient.invalidateQueries({ queryKey: ["item", itemId] });