import uuid
from datetime import datetime
from sqlalchemy import DateTime, func
from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column

class Base(DeclarativeBase):
    pass

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

class UUIDMixin:
    id: Mapped[str] = mapped_column(
        primary_key=True, default=lambda: str(uuid.uuid4())
    )