from rest_framework import generics, status
from rest_framework.response import Response
from rest_framework.authentication import TokenAuthentication
from drf_yasg.utils import swagger_auto_schema
from drf_yasg import openapi
from rest_framework.permissions import IsAuthenticated
from rest_framework.viewsets import ModelViewSet

from apps.account.serializers import (
    NotificationSerializer, 
    NotificationSendSerializer, 
    AdminNotificationSerializer, 
    NotificationTemplateSerializer
)
from apps.account.models import Notification, User, NotificationTemplate
from apps.account.tasks import send_notification_task
from utils.pagination import StandardResultsSetPagination
from apps.account.permissions import IsSuperAdmin
import logging

logger = logging.getLogger(__name__)


from drf_spectacular.utils import extend_schema, OpenApiResponse, inline_serializer
from rest_framework import serializers

class NotificationListView(generics.ListAPIView):
    serializer_class = NotificationSerializer
    permission_classes = [IsAuthenticated]
    authentication_classes = [TokenAuthentication]
    pagination_class = StandardResultsSetPagination 

    @extend_schema(
        summary="Retrieve user notifications",
        description="Retrieve a paginated list of notifications for the authenticated user.",
        tags=['Notifications'],
        responses={200: NotificationSerializer(many=True)},
    )
    def get(self, request, *args, **kwargs):
        return super().get(request, *args, **kwargs)

    def get_queryset(self):
        if getattr(self, 'swagger_fake_view', False) or not self.request.user.is_authenticated:
            return Notification.objects.none()
        return Notification.objects.filter(user=self.request.user).order_by('-created_at')


class NotificationReadAllView(generics.GenericAPIView):
    permission_classes = [IsAuthenticated]
    authentication_classes = [TokenAuthentication]
    serializer_class = serializers.Serializer

    @extend_schema(
        summary="Mark all notifications as read",
        description="Mark all notifications as read for the authenticated user.",
        tags=['Notifications'],
        request=None,
        responses={200: OpenApiResponse(description="All notifications marked as read")}
    )
    def post(self, request, *args, **kwargs):
        Notification.objects.filter(user=request.user, is_read=False).update(is_read=True)
        return Response({'status': 'all notifications marked as read'}, status=status.HTTP_200_OK)


class SendNotificationSerializer(serializers.Serializer):
    user_id = serializers.IntegerField(help_text='Target User ID')
    title = serializers.CharField(max_length=255, help_text='Notification title')
    body = serializers.CharField(help_text='Notification body')
    data = serializers.DictField(required=False, default=dict, help_text='Extra payload data')


class SendNotificationView(generics.GenericAPIView):
    permission_classes = [IsAuthenticated]
    authentication_classes = [TokenAuthentication]
    serializer_class = SendNotificationSerializer

    @extend_schema(
        summary="Send notification to user",
        description="Dispatch an in-app notification to a specific user.",
        tags=['Notifications'],
        request=SendNotificationSerializer,
        responses={
            200: OpenApiResponse(description='Notification dispatched.'),
            404: OpenApiResponse(description='User not found.'),
        }
    )
    def post(self, request, *args, **kwargs):
        serializer = self.get_serializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        user_id = serializer.validated_data.get('user_id')
        title = serializer.validated_data.get('title')
        body = serializer.validated_data.get('body')
        data = serializer.validated_data.get('data', {})

        if not User.objects.filter(id=user_id).exists():
            return Response({'error': 'User not found.'}, status=status.HTTP_404_NOT_FOUND)

        send_notification_task.delay(user_id=user_id, title=title, body=body, data=data)
        return Response({'status': 'notification queued'}, status=status.HTTP_200_OK)


class AdminNotificationViewSet(ModelViewSet):
    queryset = Notification.objects.all().select_related('user')
    serializer_class = AdminNotificationSerializer
    permission_classes = [IsAuthenticated, IsSuperAdmin]
    authentication_classes = [TokenAuthentication]
    pagination_class = StandardResultsSetPagination


class AdminNotificationTemplateViewSet(ModelViewSet):
    queryset = NotificationTemplate.objects.all()
    serializer_class = NotificationTemplateSerializer
    permission_classes = [IsAuthenticated, IsSuperAdmin]
    authentication_classes = [TokenAuthentication]
    pagination_class = StandardResultsSetPagination