How can I get the parent's argument to FieldResolver?

book.resolver.ts

import { getRepository } from 'typeorm';
import { Resolver, Query, Args, Arg, Mutation, Authorized, FieldResolver, Root, Ctx } from 'type-graphql';
import { Book, BookFilter, BooksFilter, CreateBookInput } from './book.entity';
import { Author, AuthorInput } from '../author/author.entity';
import { Category, CategoryInput } from '../category/category.entity';
import { AuthorBook } from '../author-book/author-book.entity';
import { BookReadingStatus } from '../book-reading-status/book-reading-status.entity';
import { BookLike } from '../book-like/book-like.entity';
import { UserLibrary } from '../user-library/user-library.entity';
import { BookRating } from '../book-rating/book-rating.entity';

@Resolver(Book)
export class BookResolver {


    @Query(() => Book, { nullable: true })
    async book(
        @Args() { id, title, slug }: BookFilter
    ): Promise<Book> {
        if (id) { return this.bookRepository.findOne({ id }); }
        if (title) { return this.bookRepository.findOne({ title }); }
        if (slug) { return this.bookRepository.findOne({ slug }); }
    }

    @Query(() => [Book])
    async allBooks(
        @Args() { title, skip, take }: BooksFilter
    ): Promise<Book[]> {
        if (title) { return this.bookRepository.find({ where: `"title" ILIKE '${title}%'`, skip, take }); }
        return this.bookRepository.find({ skip, take });
    }

   
    @Authorized('ADMIN', 'MODERATOR', 'MEMBER')
    @FieldResolver(() => BookReadingStatus, { nullable: true })
    async bookReadingStatus(
        @Root() book: Book,
        @Ctx() context: any
    ): Promise<BookReadingStatus> {
        const bookId = book.id;
        const userId = context.req.session.userId;
        const data = await this.bookReadingStatusRepository.findOne({ userId, bookId });
        return data;
    }
      
}

How can I get the parent's argument to FieldResolver?