from rest_framework import viewsets, filters
from rest_framework.permissions import IsAuthenticated
from rest_framework.decorators import action
from rest_framework.response import Response
from django_filters.rest_framework import DjangoFilterBackend
from utils.permissions import ClubFilterBackend, ClubLevelPermission
from .models import Trainer
from .serializers import TrainerSerializer
from wrestleDesk.pagination import StandardResultsSetPagination


class TrainerViewSet(viewsets.ModelViewSet):
    queryset = Trainer.objects.select_related('club').all()
    serializer_class = TrainerSerializer
    pagination_class = StandardResultsSetPagination
    permission_classes = [IsAuthenticated]
    filter_backends = [DjangoFilterBackend, filters.SearchFilter, filters.OrderingFilter]
    filterset_fields = ['club', 'is_active']
    search_fields = ['first_name', 'last_name', 'email']
    ordering_fields = ['last_name', 'first_name', 'created_at']

    @action(detail=False, methods=['get'])
    def available_for_training(self, request):
        """
        Returns ALL trainers without club filtering.
        Used when selecting trainers for a training session
        where trainers from other clubs may attend.
        """
        queryset = Trainer.objects.select_related('club').filter(is_active=True)
        
        search = request.query_params.get('search')
        if search:
            queryset = queryset.filter(first_name__icontains=search) | queryset.filter(last_name__icontains=search)
        
        queryset = queryset.order_by('last_name', 'first_name')
        
        page = self.paginate_queryset(queryset)
        if page is not None:
            serializer = self.get_serializer(page, many=True)
            return self.get_paginated_response(serializer.data)
        
        serializer = self.get_serializer(queryset, many=True)
        return Response(serializer.data)