from __future__ import annotations

from datetime import datetime, timezone
from uuid import uuid4

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


NAMING_CONVENTION = {
    "ix": "ix_%(column_0_label)s",
    "uq": "uq_%(table_name)s_%(column_0_name)s",
    "ck": "ck_%(table_name)s_%(constraint_name)s",
    "fk": "fk_%(table_name)s_%(column_0_name)s_%(referred_table_name)s",
    "pk": "pk_%(table_name)s",
}


def utcnow() -> datetime:
    return datetime.now(timezone.utc)


def new_id() -> str:
    return uuid4().hex


class Base(DeclarativeBase):
    metadata = MetaData(naming_convention=NAMING_CONVENTION)


class UUIDPrimaryKeyMixin:
    id: Mapped[str] = mapped_column(
        String(32),
        primary_key=True,
        default=new_id,
    )


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