"""Reusable model mixins."""
from datetime import datetime

from sqlalchemy import DateTime, func
from sqlalchemy.orm import Mapped, mapped_column


class TimestampMixin:
    """Adds created_at / updated_at columns managed by the database itself."""

    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), server_default=func.now(), onupdate=func.now()
    )