fix(favorites): scope reorder position writes by playlist

The global favorites reorder wrote the new position filtering only by
content_id, so two Xtream playlists holding a favorite with the same
content_id would clobber each other's persisted order (greptile P1).

Thread playlist_id through the whole reorder path — the renderer builder
(UnifiedCollectionItem already carries playlistId), the IPC contract
(ElectronBridgeFavoriteReorderUpdate + inline payload types), the worker
op — and scope the prepared UPDATE by (contentId, playlistId), matching
the favorites composite unique index.

Tests: favorites.operations.spec asserts the playlistId placeholder and
per-row playlistId payload; preload contract fixture updated.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/electron-backend/src/app/api/main.preload.spec-data.ts

@@ -34,7 +34,9 @@ const streams = [{ stream_id: 42, name: 'Channel' }];
 const favorites = [{ contentId: 1, playlistId }];
 const recentlyViewed = [{ contentId: 2, playlistId }];
 const categoryIds = [10, 11];
-const reorderUpdates = [{ content_id: 12, position: 1 }];
+const reorderUpdates = [
+    { content_id: 12, playlist_id: 'playlist-1', position: 1 },
+];
 const recentItemsBatch = [{ contentId: 13, playlistId }];
 const playbackData = {
     contentXtreamId: 42,

apps/electron-backend/src/app/api/main.preload.ts

@@ -710,7 +710,7 @@ const electronApi: ElectronBridgeApi = {
     dbGetAllGlobalFavorites: () =>
         ipcRenderer.invoke('DB_GET_ALL_GLOBAL_FAVORITES'),
     dbReorderGlobalFavorites: (
-        updates: { content_id: number; position: number }[]
+        updates: { content_id: number; playlist_id: string; position: number }[]
     ) => ipcRenderer.invoke('DB_REORDER_GLOBAL_FAVORITES', updates),
     // Recently viewed (playlist-specific)
     dbGetRecentItems: (playlistId: string) =>

apps/electron-backend/src/app/database/operations/favorites.operations.spec.ts

@@ -111,15 +111,19 @@ describe('favorites.operations', () => {
 
             await expect(
                 reorderGlobalFavorites(db, [
-                    { content_id: 30, position: 0 },
+                    { content_id: 30, playlist_id: 'p1', position: 0 },
-                    { content_id: 10, position: 1 },
+                    { content_id: 10, playlist_id: 'p1', position: 1 },
-                    { content_id: 20, position: 2 },
+                    { content_id: 20, playlist_id: 'p2', position: 2 },
                 ])
             ).resolves.toEqual({ success: true });
 
             expect(updatePrepare).toHaveBeenCalledTimes(1);
             expect(placeholderMock).toHaveBeenCalledWith('position');
             expect(placeholderMock).toHaveBeenCalledWith('contentId');
+            // Regression: favorites are playlist-scoped, so the UPDATE must
+            // filter by playlistId too — otherwise a same-contentId favorite
+            // in another playlist gets its position silently rewritten.
+            expect(placeholderMock).toHaveBeenCalledWith('playlistId');
             expect(transaction).toHaveBeenCalledTimes(1);
 
             // Regression (issue #1137): the prepared UPDATE must be dispatched
@@ -131,14 +135,17 @@ describe('favorites.operations', () => {
             expect(updateRun).toHaveBeenNthCalledWith(1, {
                 position: 0,
                 contentId: 30,
+                playlistId: 'p1',
             });
             expect(updateRun).toHaveBeenNthCalledWith(2, {
                 position: 1,
                 contentId: 10,
+                playlistId: 'p1',
             });
             expect(updateRun).toHaveBeenNthCalledWith(3, {
                 position: 2,
                 contentId: 20,
+                playlistId: 'p2',
             });
         });
     });

apps/electron-backend/src/app/database/operations/favorites.operations.ts

@@ -140,7 +140,7 @@ function selectGlobalFavoriteRows(
 
 export async function reorderGlobalFavorites(
     db: AppDatabase,
-    updates: { content_id: number; position: number }[],
+    updates: { content_id: number; playlist_id: string; position: number }[],
     control?: OperationControl
 ): Promise<{ success: boolean }> {
     if (!Array.isArray(updates) || updates.length === 0) {
@@ -152,17 +152,25 @@ export async function reorderGlobalFavorites(
 
     // Drizzle's .set() doesn't accept a bare Placeholder — wrap it in an
     // sql template so the value resolves to SQL<number> at compile time.
+    // Scope by (contentId, playlistId): the favorites table is
+    // playlist-scoped, so filtering by contentId alone would also rewrite
+    // the position of a same-contentId favorite in another playlist.
     const updateFavoritePosition = db
         .update(schema.favorites)
         .set({ position: sql<number>`${sql.placeholder('position')}` })
-        .where(eq(schema.favorites.contentId, sql.placeholder('contentId')))
+        .where(
+            and(
+                eq(schema.favorites.contentId, sql.placeholder('contentId')),
+                eq(schema.favorites.playlistId, sql.placeholder('playlistId'))
+            )
+        )
         .prepare();
 
     for (const chunk of chunkValues(updates, DEFAULT_BATCH_SIZE)) {
         await checkpointOperation(control);
 
         await db.transaction(() => {
-            for (const { content_id, position } of chunk) {
+            for (const { content_id, playlist_id, position } of chunk) {
                 // Must be .run() (synchronous), NOT .execute(): on the
                 // better-sqlite3 driver .execute() defers the write to a
                 // resolved promise, which never settles inside this
@@ -172,6 +180,7 @@ export async function reorderGlobalFavorites(
                 updateFavoritePosition.run({
                     position,
                     contentId: content_id,
+                    playlistId: playlist_id,
                 });
             }
         });

apps/electron-backend/src/app/events/database/favorites.events.ts

@@ -39,7 +39,7 @@ handleWorkerRequest('DB_GET_ALL_GLOBAL_FAVORITES', () => ({}));
 
 handleWorkerRequest(
     'DB_REORDER_GLOBAL_FAVORITES',
-    (updates: { content_id: number; position: number }[]) => ({
+    (updates: { content_id: number; playlist_id: string; position: number }[]) => ({
         updates,
     })
 );

apps/electron-backend/src/app/workers/database.worker.ts

@@ -770,7 +770,7 @@ async function executeRequest(message: DbWorkerRequestMessage) {
 
         case 'DB_REORDER_GLOBAL_FAVORITES': {
             const payload = message.payload as {
-                updates: { content_id: number; position: number }[];
+                updates: { content_id: number; playlist_id: string; position: number }[];
             };
             return reorderGlobalFavorites(db, payload.updates);
         }

libs/portal/shared/data-access/src/lib/collection/unified-favorites-data.service.ts

@@ -807,12 +807,17 @@ export class UnifiedFavoritesDataService {
     }
 
     private buildXtreamPositionUpdates(items: UnifiedCollectionItem[]) {
-        const updates: { content_id: number; position: number }[] = [];
+        const updates: {
+            content_id: number;
+            playlist_id: string;
+            position: number;
+        }[] = [];
 
         for (const item of items) {
             if (item.sourceType === 'xtream' && item.contentId != null) {
                 updates.push({
                     content_id: item.contentId,
+                    playlist_id: item.playlistId,
                     position: updates.length,
                 });
             }

libs/shared/interfaces/src/lib/electron-api.interface.ts

@@ -414,6 +414,8 @@ export interface ElectronBridgeGlobalRecentlyAddedItem extends ElectronBridgeXtr
 
 export interface ElectronBridgeFavoriteReorderUpdate {
     content_id: number;
+    /** Favorites are playlist-scoped — scope the position write per playlist */
+    playlist_id: string;
     position: number;
 }