"""Base model with common columns shared by all bx_ tables."""

from datetime import datetime
from sqlalchemy import BigInteger, String, SmallInteger, DateTime, func
from sqlalchemy.orm import Mapped, mapped_column, DeclarativeBase

from app.database import Base


class BaseModel(Base):
    """Abstract base providing id, create_by, create_time, update_by, update_time."""
    __abstract__ = True

    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
    create_by: Mapped[str | None] = mapped_column(String(64), default=None)
    create_time: Mapped[datetime] = mapped_column(
        DateTime, nullable=False, server_default=func.now()
    )
    update_by: Mapped[str | None] = mapped_column(String(64), default=None)
    update_time: Mapped[datetime] = mapped_column(
        DateTime, nullable=False, server_default=func.now(), onupdate=func.now()
    )


class SoftDeleteMixin:
    """Mixin for soft-delete support (del_flag column)."""
    del_flag: Mapped[int] = mapped_column(
        SmallInteger, nullable=False, default=0, server_default="0"
    )