from sqlalchemy import Boolean, CheckConstraint, func
from sqlalchemy.orm import Mapped, mapped_column
from datetime import datetime
from app.database import Base


class SystemConfig(Base):
    """
    Singleton system configuration table (always id=1).
    Stores global toggles for registration, MFA enforcement, etc.
    """
    __tablename__ = "system_config"
    __table_args__ = (
        CheckConstraint("id = 1", name="ck_system_config_singleton"),
    )

    id: Mapped[int] = mapped_column(primary_key=True)
    allow_registration: Mapped[bool] = mapped_column(
        Boolean, default=False, server_default="false"
    )
    enforce_mfa_new_users: Mapped[bool] = mapped_column(
        Boolean, default=False, server_default="false"
    )
    allow_passwordless: Mapped[bool] = mapped_column(
        Boolean, default=False, server_default="false"
    )
    created_at: Mapped[datetime] = mapped_column(default=func.now(), server_default=func.now())
    updated_at: Mapped[datetime] = mapped_column(
        default=func.now(), onupdate=func.now(), server_default=func.now()
    )