fix(vod): respect relation_id when switching providers in SeriesModal/VODModal

The provider-info endpoints for both series and movies always returned
data from the highest-priority relation, ignoring the provider the user
had selected in the dropdown. Switching sources in the UI produced no
change in the episode list or movie details.

Root cause: the endpoints had no support for a relation_id query param,
and the frontend never passed one when the user changed the selection.

Fix (backend):
- series provider-info: accept ?relation_id=<id> and query that specific
  M3USeriesRelation; fall back to highest-priority when omitted
- movie provider-info: same treatment for M3UMovieRelation

Fix (frontend):
- api.getSeriesInfo / api.getMovieProviderInfo accept an optional
  relationId argument and append it to the query string
- useVODStore.fetchSeriesInfo / fetchMovieDetailsFromProvider forward
  the argument to the API layer
- SeriesModal.onChangeSelectedProvider re-fetches series info (episodes
  included) with the newly selected relation's id
- VODModal.onChangeSelectedProvider re-fetches movie details with the
  newly selected relation's id

Fixes #1250

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/vod/api_views.py

@@ -120,11 +120,21 @@ class MovieViewSet(viewsets.ReadOnlyModelViewSet):
         """Get detailed movie information from the original provider, throttled to 24h."""
         movie = self.get_object()
 
-        # Get the highest priority active relation
-        relation = M3UMovieRelation.objects.filter(
+        relation_id = request.query_params.get('relation_id')
+        qs = M3UMovieRelation.objects.filter(
             movie=movie,
             m3u_account__is_active=True
-        ).select_related('m3u_account').order_by('-m3u_account__priority', 'id').first()
+        ).select_related('m3u_account')
+
+        if relation_id:
+            relation = qs.filter(id=relation_id).first()
+            if not relation:
+                return Response(
+                    {'error': 'Relation not found or not active'},
+                    status=status.HTTP_404_NOT_FOUND
+                )
+        else:
+            relation = qs.order_by('-m3u_account__priority', 'id').first()
 
         if not relation:
             return Response(
@@ -326,11 +336,21 @@ class SeriesViewSet(viewsets.ReadOnlyModelViewSet):
         series = self.get_object()
         logger.debug(f"Retrieved series: {series.name} (ID: {series.id})")
 
-        # Get the highest priority active relation
-        relation = M3USeriesRelation.objects.filter(
+        relation_id = request.query_params.get('relation_id')
+        qs = M3USeriesRelation.objects.filter(
             series=series,
             m3u_account__is_active=True
-        ).select_related('m3u_account').order_by('-m3u_account__priority', 'id').first()
+        ).select_related('m3u_account')
+
+        if relation_id:
+            relation = qs.filter(id=relation_id).first()
+            if not relation:
+                return Response(
+                    {'error': 'Relation not found or not active'},
+                    status=status.HTTP_404_NOT_FOUND
+                )
+        else:
+            relation = qs.order_by('-m3u_account__priority', 'id').first()
 
         if not relation:
             return Response(

frontend/src/api.js

@@ -3526,10 +3526,11 @@ export default class API {
     }
   }
 
-  static async getMovieProviderInfo(movieId) {
+  static async getMovieProviderInfo(movieId, relationId = null) {
     try {
+      const params = relationId ? `?relation_id=${relationId}` : '';
       const response = await request(
-        `${host}/api/vod/movies/${movieId}/provider-info/`
+        `${host}/api/vod/movies/${movieId}/provider-info/${params}`
       );
       return response;
     } catch (e) {
@@ -3568,11 +3569,12 @@ export default class API {
     }
   }
 
-  static async getSeriesInfo(seriesId) {
+  static async getSeriesInfo(seriesId, relationId = null) {
     try {
-      // Call the provider-info endpoint that includes episodes
+      const params = new URLSearchParams({ include_episodes: 'true' });
+      if (relationId) params.set('relation_id', relationId);
       const response = await request(
-        `${host}/api/vod/series/${seriesId}/provider-info/?include_episodes=true`
+        `${host}/api/vod/series/${seriesId}/provider-info/?${params}`
       );
       return response;
     } catch (e) {

frontend/src/components/SeriesModal.jsx

@@ -470,6 +470,13 @@ const SeriesModal = ({ series, opened, onClose }) => {
   const onChangeSelectedProvider = (value) => {
     const provider = providers.find((p) => p.id.toString() === value);
     setSelectedProvider(provider);
+    if (provider) {
+      setLoadingDetails(true);
+      fetchSeriesInfo(series.id, provider.id)
+        .then((details) => setDetailedSeries(details))
+        .catch(() => {})
+        .finally(() => setLoadingDetails(false));
+    }
   };
 
   if (!series) return null;

frontend/src/components/VODModal.jsx

@@ -324,6 +324,11 @@ const VODModal = ({ vod, opened, onClose }) => {
   const onChangeSelectedProvider = (value) => {
     const provider = providers.find((p) => p.id.toString() === value);
     setSelectedProvider(provider);
+    if (provider) {
+      fetchMovieDetailsFromProvider(vod.id, provider.id)
+        .then((details) => setDetailedVOD(details))
+        .catch(() => {});
+    }
   }
 
   if (!vod) return null;

frontend/src/store/useVODStore.jsx

@@ -240,10 +240,10 @@ const useVODStore = create((set, get) => ({
     }
   },
 
-  fetchMovieDetailsFromProvider: async (movieId) => {
+  fetchMovieDetailsFromProvider: async (movieId, relationId = null) => {
     set({ loading: true, error: null });
     try {
-      const response = await api.getMovieProviderInfo(movieId);
+      const response = await api.getMovieProviderInfo(movieId, relationId);
 
       // Transform the response data to match our expected format
       const movieDetails = getMovieDetailsWithProvider(response, movieId);
@@ -346,10 +346,10 @@ const useVODStore = create((set, get) => ({
       return { content: updatedContent };
     }),
 
-  fetchSeriesInfo: async (seriesId) => {
+  fetchSeriesInfo: async (seriesId, relationId = null) => {
     set({ loading: true, error: null });
     try {
-      const response = await api.getSeriesInfo(seriesId);
+      const response = await api.getSeriesInfo(seriesId, relationId);
 
       // Transform the response data to match our expected format
       const seriesInfo = getSeriesDetails(response, seriesId);