from rest_framework import status
from rest_framework.response import Response
from rest_framework.views import APIView

from core.apps.documents.models import ExecutorInfoModel
from core.apps.documents.serializers.executor import ExecutorInfoSerializer


class ExecutorInfoView(APIView):
    """Singleton endpoint — faqat bitta ExecutorInfo yozuvi bo'ladi."""

    def get(self, request, *args, **kwargs):
        instance = ExecutorInfoModel.objects.order_by("created_at").first()
        if not instance:
            return Response({}, status=status.HTTP_200_OK)
        return Response(ExecutorInfoSerializer(instance).data)

    def post(self, request, *args, **kwargs):
        if ExecutorInfoModel.objects.exists():
            return Response(
                {"detail": "ExecutorInfo allaqachon mavjud. Yangilash uchun PUT/PATCH ishlating."},
                status=status.HTTP_400_BAD_REQUEST,
            )
        serializer = ExecutorInfoSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        serializer.save()
        return Response(serializer.data, status=status.HTTP_201_CREATED)

    def put(self, request, *args, **kwargs):
        return self._upsert(request, partial=False)

    def patch(self, request, *args, **kwargs):
        return self._upsert(request, partial=True)

    def delete(self, request, *args, **kwargs):
        instance = ExecutorInfoModel.objects.order_by("created_at").first()
        if not instance:
            return Response(status=status.HTTP_404_NOT_FOUND)
        instance.delete()
        return Response(status=status.HTTP_204_NO_CONTENT)

    def _upsert(self, request, partial):
        instance = ExecutorInfoModel.objects.order_by("created_at").first()
        serializer = ExecutorInfoSerializer(instance, data=request.data, partial=partial)
        serializer.is_valid(raise_exception=True)
        serializer.save()
        return Response(serializer.data)