from __future__ import annotations

from datetime import datetime, timezone
from decimal import Decimal

from sqlalchemy import Boolean, CheckConstraint, DateTime, Numeric, String, Text
from sqlalchemy.orm import Mapped, mapped_column

from app.models.base import Base


class Product(Base):
    __tablename__ = "products"
    __table_args__ = (
        CheckConstraint("price > 0", name="ck_products_price_positive"),
        CheckConstraint("stock >= 0", name="ck_products_stock_non_negative"),
    )

    id: Mapped[int] = mapped_column(primary_key=True)
    name: Mapped[str] = mapped_column(String(120), nullable=False, index=True)
    description: Mapped[str | None] = mapped_column(Text, nullable=True)
    price: Mapped[Decimal] = mapped_column(Numeric(10, 2), nullable=False)
    stock: Mapped[int] = mapped_column(nullable=False, default=0)
    is_active: Mapped[bool] = mapped_column(Boolean, nullable=False, default=True)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        default=lambda: datetime.now(timezone.utc),
        nullable=False,
    )