from sqlalchemy import Column, DateTime, ForeignKey, Integer
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func

from app.db.session import Base


class Cart(Base):
    __tablename__ = "carts"

    id = Column(Integer, primary_key=True, index=True)
    user_id = Column(Integer, ForeignKey("users.id"), unique=True, nullable=False)

    # Relationships
    user = relationship("User", backref="cart", uselist=False)
    items = relationship("CartItem", back_populates="cart", cascade="all, delete-orphan")
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), onupdate=func.now())


class CartItem(Base):
    __tablename__ = "cart_items"

    id = Column(Integer, primary_key=True, index=True)
    cart_id = Column(Integer, ForeignKey("carts.id"), nullable=False)
    product_id = Column(Integer, ForeignKey("products.id"), nullable=False)
    quantity = Column(Integer, nullable=False, default=1)

    # Relationships
    cart = relationship("Cart", back_populates="items")
    product = relationship("Product", back_populates="cart_items")
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), onupdate=func.now())