from sqlalchemy import Column, String, Integer, DateTime, ForeignKey
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func
from core.database import Base
import uuid

class Book(Base):
    __tablename__ = "books"
    
    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
    title = Column(String, nullable=False, index=True)
    description = Column(String)
    isbn = Column(String, unique=True)
    publication_year = Column(Integer)
    author_id = Column(String, ForeignKey("authors.id"), nullable=False)
    
    author = relationship("Author", back_populates="books")
    
    created_at = Column(DateTime, default=func.now())
    updated_at = Column(DateTime, default=func.now(), onupdate=func.now())