from rest_framework import viewsets, status
from rest_framework.response import Response
from rest_framework.decorators import action
from django.contrib.auth.models import User
from .models import StickerTransferRequest, StickerTransferItem, Sticker, StickerMovement
from .serializers import StickerTransferRequestSerializer, StickerTransferItemSerializer
from django.shortcuts import get_object_or_404
from django.utils import timezone

class StickerTransferRequestViewSet(viewsets.ModelViewSet):
    queryset = StickerTransferRequest.objects.all().select_related('from_user', 'to_user').prefetch_related('items__sticker')
    serializer_class = StickerTransferRequestSerializer

    def get_queryset(self):
        user = self.request.user
        return StickerTransferRequest.objects.filter(from_user=user) | StickerTransferRequest.objects.filter(to_user=user)

    def perform_create(self, serializer):
        serializer.save(from_user=self.request.user)

    @action(detail=True, methods=['post'])
    def accept(self, request, pk=None):
        transfer = get_object_or_404(StickerTransferRequest, pk=pk)

        if transfer.to_user != request.user:
            return Response({"error": "Нет прав для принятия этой передачи."}, status=status.HTTP_403_FORBIDDEN)

        if transfer.status != 'pending':
            return Response({"error": "Передача уже обработана."}, status=status.HTTP_400_BAD_REQUEST)

        # Перемещение стикеров
        for item in transfer.items.all():
            StickerMovement.objects.create(
                sticker=item.sticker,
                from_location='склад',
                to_location='цех',
                quantity=item.quantity
            )
            item.sticker.location = 'цех'
            item.sticker.save()

        transfer.status = 'accepted'
        transfer.save()
        return Response({"status": "Принята"})

    @action(detail=True, methods=['post'])
    def decline(self, request, pk=None):
        transfer = get_object_or_404(StickerTransferRequest, pk=pk)

        if transfer.to_user != request.user:
            return Response({"error": "Нет прав для отклонения этой передачи."}, status=status.HTTP_403_FORBIDDEN)

        if transfer.status != 'pending':
            return Response({"error": "Передача уже обработана."}, status=status.HTTP_400_BAD_REQUEST)

        transfer.status = 'declined'
        transfer.save()
        return Response({"status": "Отклонена"})