from django.http import JsonResponse
from adrf.views import APIView
from rest_framework import status
from rest_framework.decorators import permission_classes
from rest_framework.permissions import AllowAny
from asgiref.sync import sync_to_async
from ..models import CompressionHistory
from ..serializers import CompressionHistorySerializer


@permission_classes([AllowAny])
class CompressionHistoryListView(APIView):
    async def get(self, request):
        user = request.user if request.user.is_authenticated else None
        session_id = request.query_params.get('session_id')

        if user:
            histories = CompressionHistory.objects.filter(user=user)
        elif session_id:
            histories = CompressionHistory.objects.filter(session_id=session_id)
        else:
            return JsonResponse({
                'success': True,
                'data': [],
                'total': 0
            })

        page = int(request.query_params.get('page', 1))
        page_size = int(request.query_params.get('page_size', 20))
        start = (page - 1) * page_size
        end = start + page_size

        total = await histories.acount()
        serializer = CompressionHistorySerializer([h async for h in histories[start:end]], many=True)

        return JsonResponse({
            'success': True,
            'data': serializer.data,
            'total': total,
            'page': page,
            'page_size': page_size
        })

    async def post(self, request):
        data = request.data.copy()

        if request.user.is_authenticated:
            data['user'] = request.user.id

        serializer = CompressionHistorySerializer(data=data)
        if serializer.is_valid():
            # DRF 序列化器 save() 为同步 ORM 操作，sync_to_async 兜底
            await sync_to_async(serializer.save)()
            return JsonResponse({
                'success': True,
                'data': serializer.data
            }, status=status.HTTP_201_CREATED)

        return JsonResponse({
            'error': '参数错误',
            'details': serializer.errors
        }, status=status.HTTP_400_BAD_REQUEST)


@permission_classes([AllowAny])
class CompressionHistoryDetailView(APIView):
    async def delete(self, request, pk):
        user = request.user if request.user.is_authenticated else None
        session_id = request.query_params.get('session_id')

        try:
            if user:
                history = await CompressionHistory.objects.aget(pk=pk, user=user)
            elif session_id:
                history = await CompressionHistory.objects.aget(pk=pk, session_id=session_id)
            else:
                return JsonResponse(
                    {'error': '无权限删除'},
                    status=status.HTTP_403_FORBIDDEN
                )

            await history.adelete()
            return JsonResponse({'success': True})
        except CompressionHistory.DoesNotExist:
            return JsonResponse(
                {'error': '记录不存在'},
                status=status.HTTP_404_NOT_FOUND
            )


@permission_classes([AllowAny])
class CompressionHistoryClearView(APIView):
    async def delete(self, request):
        user = request.user if request.user.is_authenticated else None
        session_id = request.query_params.get('session_id')

        if user:
            count, _ = await CompressionHistory.objects.filter(user=user).adelete()
        elif session_id:
            count, _ = await CompressionHistory.objects.filter(session_id=session_id).adelete()
        else:
            return JsonResponse(
                {'error': '无权限清空'},
                status=status.HTTP_403_FORBIDDEN
            )

        return JsonResponse({
            'success': True,
            'deleted_count': count
        })