from django.shortcuts import get_object_or_404
from rest_framework import parsers, permissions, status, viewsets
from rest_framework.decorators import action
from rest_framework.request import Request
from rest_framework.response import Response

from books.models import Book, ReadingProgress, ReadingSettings
from books.serializers import (
    BookDetailSerializer,
    BookListSerializer,
    BookUploadSerializer,
    ReadingProgressSerializer,
    ReadingSettingsSerializer,
)


class IsBookOwner(permissions.BasePermission):
    """Only the owner of a book can access it."""

    def has_object_permission(
        self, request: Request, view: object, obj: Book
    ) -> bool:
        return obj.user == request.user


class BookViewSet(viewsets.ModelViewSet):
    """API endpoint for managing user books."""

    parser_classes = [parsers.MultiPartParser, parsers.FormParser, parsers.JSONParser]
    permission_classes = [permissions.IsAuthenticated, IsBookOwner]

    def get_serializer_class(self) -> type:
        if self.action == "create":
            return BookUploadSerializer
        if self.action == "list":
            return BookListSerializer
        return BookDetailSerializer

    def get_queryset(self):
        return (
            Book.objects.filter(user=self.request.user)
            .select_related("reading_progress", "user")
            .prefetch_related()
        )

    @action(detail=True, methods=["get", "patch"])
    def progress(self, request: Request, pk: int | None = None) -> Response:
        """Get or update reading progress for a specific book."""
        book = self.get_object()
        progress, _created = ReadingProgress.objects.get_or_create(
            user=request.user,
            book=book,
        )

        if request.method == "GET":
            serializer = ReadingProgressSerializer(progress)
            return Response(serializer.data)

        serializer = ReadingProgressSerializer(progress, data=request.data, partial=True)
        serializer.is_valid(raise_exception=True)
        serializer.save()
        return Response(serializer.data)


class ReadingSettingsViewSet(viewsets.GenericViewSet):
    """API endpoint for user reading settings."""

    permission_classes = [permissions.IsAuthenticated]
    serializer_class = ReadingSettingsSerializer

    def get_queryset(self):
        return ReadingSettings.objects.filter(user=self.request.user)

    def list(self, request: Request) -> Response:
        settings, _created = ReadingSettings.objects.get_or_create(
            user=request.user,
        )
        serializer = self.get_serializer(settings)
        return Response(serializer.data)

    def partial_update(self, request: Request) -> Response:
        settings, _created = ReadingSettings.objects.get_or_create(
            user=request.user,
        )
        serializer = self.get_serializer(settings, data=request.data, partial=True)
        serializer.is_valid(raise_exception=True)
        serializer.save()
        return Response(serializer.data)