"""Declarative base + shared mixins for all ORM models."""

from __future__ import annotations

import uuid
from datetime import UTC, datetime

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


def utcnow() -> datetime:
    return datetime.now(UTC)


def ensure_aware_utc(value: datetime) -> datetime:
    """SQLite's `DateTime(timezone=True)` silently drops tzinfo on read back
    (Postgres does not). Anything read from the DB and compared against an
    aware `datetime.now(UTC)` must go through this first so the app behaves
    identically on both backends."""
    if value.tzinfo is None:
        return value.replace(tzinfo=UTC)
    return value


class Base(DeclarativeBase):
    pass


class UUIDPrimaryKeyMixin:
    id: Mapped[uuid.UUID] = mapped_column(primary_key=True, default=uuid.uuid4, unique=True)


class TimestampMixin:
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), default=utcnow, onupdate=utcnow
    )