from rest_framework import serializers

from apps.shelves.serializers import ShelfSerializer
from apps.authors.serializers import AuthorSerializer
from apps.books.models import Book
from apps.shelves.models import Shelf
from apps.authors.models import Author

class BookSerializer(serializers.ModelSerializer):
    shelf = ShelfSerializer(read_only=True)
    shelf_id = serializers.PrimaryKeyRelatedField(
        queryset=Shelf.objects.all(),
        source="shelf", 
        write_only=True
    )
    
    authors = AuthorSerializer(many=True, read_only=True)
    authors_id = serializers.PrimaryKeyRelatedField(
        queryset=Author.objects.all(),
        source="authors",
        many=True,
        allow_null=True,
        write_only=True
    )
    
    class Meta: 
        model = Book
        fields = [
            "id",
            "name",
            "isbn", 
            "shelf",
            "shelf_id",
            "authors",
            "authors_id"
        ]
        read_only_fields = ["id"]
    

    def __init__(self, instance=None, data=..., **kwargs):
        super().__init__(instance, data, **kwargs)

        request = self.context.get("request")        
        if request and request.user:
            self.fields["shelf_id"].queryset = Shelf.objects.filter(
                user=request.user
            )

            self.fields["authors_id"].queryset = Author.objects.filter(
                user=request.user
            )

            
    def create(self, validated_data):
        request = self.context["request"]
        validated_data["user"] = request.user

        return super().create(validated_data)