"""
Notification views for KeepItGoing.
"""

from django.utils import timezone
from rest_framework import generics, permissions, status
from rest_framework.decorators import api_view, permission_classes
from rest_framework.response import Response

from .models import Notification
from .serializers import NotificationSerializer


class NotificationListAPIView(generics.ListAPIView):
    """API endpoint for listing notifications."""

    serializer_class = NotificationSerializer
    permission_classes = [permissions.IsAuthenticated]

    def get_queryset(self):
        queryset = Notification.objects.filter(user=self.request.user)

        # Filter by read status
        is_read = self.request.query_params.get('is_read')
        if is_read is not None:
            queryset = queryset.filter(is_read=is_read.lower() == 'true')

        return queryset


@api_view(['POST'])
@permission_classes([permissions.IsAuthenticated])
def mark_read(request, notification_id):
    """Mark a notification as read."""
    try:
        notification = Notification.objects.get(
            id=notification_id,
            user=request.user
        )
    except Notification.DoesNotExist:
        return Response(
            {'error': 'Notification not found'},
            status=status.HTTP_404_NOT_FOUND
        )

    notification.is_read = True
    notification.read_at = timezone.now()
    notification.save()

    return Response(NotificationSerializer(notification).data)


@api_view(['POST'])
@permission_classes([permissions.IsAuthenticated])
def mark_all_read(request):
    """Mark all notifications as read."""
    Notification.objects.filter(
        user=request.user,
        is_read=False
    ).update(
        is_read=True,
        read_at=timezone.now()
    )

    return Response({'status': 'All notifications marked as read'})


@api_view(['GET'])
@permission_classes([permissions.IsAuthenticated])
def unread_count(request):
    """Get count of unread notifications."""
    count = Notification.objects.filter(
        user=request.user,
        is_read=False
    ).count()

    return Response({'unread_count': count})


@api_view(['DELETE'])
@permission_classes([permissions.IsAuthenticated])
def delete_notification(request, notification_id):
    """Delete a notification."""
    try:
        notification = Notification.objects.get(
            id=notification_id,
            user=request.user
        )
    except Notification.DoesNotExist:
        return Response(
            {'error': 'Notification not found'},
            status=status.HTTP_404_NOT_FOUND
        )

    notification.delete()
    return Response(status=status.HTTP_204_NO_CONTENT)