from fastapi import APIRouter, Path, Depends, HTTPException
from sqlmodel import Session, select

from library_service.models.db.links import BookWithAuthorsAndGenres
from library_service.settings import get_session
from library_service.models.db import Author, Book, BookWithAuthors, AuthorBookLink
from library_service.models.dto import (
    AuthorRead,
    BookList,
    BookRead,
    BookCreate,
    BookUpdate,
)


router = APIRouter(prefix="/books", tags=["books"])


# Create a book
@router.post(
    "/",
    response_model=Book,
    summary="Создать книгу",
    description="Добавляет книгу в систему",
)
def create_book(book: BookCreate, session: Session = Depends(get_session)):
    db_book = Book(**book.model_dump())
    session.add(db_book)
    session.commit()
    session.refresh(db_book)
    return BookRead(**db_book.model_dump())


# Read books
@router.get(
    "/",
    response_model=BookList,
    summary="Получить список книг",
    description="Возвращает список всех книг в системе",
)
def read_books(session: Session = Depends(get_session)):
    books = session.exec(select(Book)).all()
    return BookList(
        books=[BookRead(**book.model_dump()) for book in books], total=len(books)
    )


# Read a book with their authors and genres
@router.get(
    "/{book_id}",
    response_model=BookWithAuthorsAndGenres,
    summary="Получить информацию о книге",
    description="Возвращает информацию о книге, её авторах и жанрах",
)
def get_book(
    book_id: int = Path(..., description="ID книги (целое число, > 0)", gt=0),
    session: Session = Depends(get_session),
):
    book = session.get(Book, book_id)
    if not book:
        raise HTTPException(status_code=404, detail="Book not found")

    authors = session.exec(
        select(Author).join(AuthorBookLink).where(AuthorBookLink.book_id == book_id)
    ).all()

    author_reads = [AuthorRead(**author.model_dump()) for author in authors]

    genres = session.exec(
        select(Genre).join(GenreBookLink).where(GenreBookLink.book_id == book_id)
    ).all()

    genre_reads = [GenreRead(**genre.model_dump()) for genre in genres]

    book_data = book.model_dump()
    book_data["authors"] = author_reads
    book_data["genres"] = genre_reads

    return BookWithAuthors(**book_data)


# Update a book
@router.put(
    "/{book_id}",
    response_model=Book,
    summary="Обновить информацию о книге",
    description="Обновляет информацию о книге в системе",
)
def update_book(
    book: BookUpdate,
    book_id: int = Path(..., description="ID книги (целое число, > 0)", gt=0),
    session: Session = Depends(get_session),
):
    db_book = session.get(Book, book_id)
    if not db_book:
        raise HTTPException(status_code=404, detail="Book not found")

    db_book.title = book.title or db_book.title
    db_book.description = book.description or db_book.description
    session.commit()
    session.refresh(db_book)
    return db_book


# Delete a book
@router.delete(
    "/{book_id}",
    response_model=BookRead,
    summary="Удалить книгу",
    description="Удаляет книгу их системы",
)
def delete_book(
    book_id: int = Path(..., description="ID книги (целое число, > 0)", gt=0),
    session: Session = Depends(get_session),
):
    book = session.get(Book, book_id)
    if not book:
        raise HTTPException(status_code=404, detail="Book not found")
    book_read = BookRead(
        id=(book.id or 0), title=book.title, description=book.description
    )
    session.delete(book)
    session.commit()
    return book_read