Refactor code structure and remove redundant changes

backend/apps/api/v1/viewsets_rankings.py

@@ -15,8 +15,7 @@ from rest_framework.response import Response
 from rest_framework.viewsets import ReadOnlyModelViewSet
 from rest_framework.views import APIView
 
-from apps.rides.models import RideRanking, RidePairComparison, RankingSnapshot
-from apps.rides.services import RideRankingService
+# Import models inside methods to avoid Django initialization issues
 from .serializers_rankings import (
     RideRankingSerializer,
     RideRankingDetailSerializer,
@@ -104,6 +103,8 @@ class RideRankingViewSet(ReadOnlyModelViewSet):
 
     def get_queryset(self):
         """Get rankings with optimized queries."""
+        from apps.rides.models import RideRanking
+
         queryset = RideRanking.objects.select_related(
             "ride", "ride__park", "ride__park__location", "ride__manufacturer"
         )
@@ -141,6 +142,8 @@ class RideRankingViewSet(ReadOnlyModelViewSet):
     @action(detail=True, methods=["get"])
     def history(self, request, ride_slug=None):
         """Get ranking history for a specific ride."""
+        from apps.rides.models import RankingSnapshot
+
         ranking = self.get_object()
         history = RankingSnapshot.objects.filter(ride=ranking.ride).order_by(
             "-snapshot_date"
@@ -154,6 +157,8 @@ class RideRankingViewSet(ReadOnlyModelViewSet):
     @action(detail=False, methods=["get"])
     def statistics(self, request):
         """Get overall ranking system statistics."""
+        from apps.rides.models import RideRanking, RidePairComparison, RankingSnapshot
+
         total_rankings = RideRanking.objects.count()
         total_comparisons = RidePairComparison.objects.count()
 
@@ -246,6 +251,8 @@ class RideRankingViewSet(ReadOnlyModelViewSet):
     @action(detail=True, methods=["get"])
     def comparisons(self, request, ride_slug=None):
         """Get head-to-head comparisons for a specific ride."""
+        from apps.rides.models import RidePairComparison
+
         ranking = self.get_object()
 
         comparisons = (
@@ -326,6 +333,8 @@ class TriggerRankingCalculationView(APIView):
                 {"error": "Admin access required"}, status=status.HTTP_403_FORBIDDEN
             )
 
+        from apps.rides.services import RideRankingService
+
         category = request.data.get("category")
 
         service = RideRankingService()