from datetime import datetime
from typing import Optional
from sqlalchemy import Integer, String, DateTime, ForeignKey, JSON
from sqlalchemy.orm import Mapped, mapped_column, relationship
from sqlalchemy.sql import func
from src.apps.base.models.base import Base


class MerchantAuditLog(Base):
    """
    MerchantAuditLog Model: Immutable log of RBAC-related actions within a merchant account.
    Covers role assignments, invitations, ownership transfers, and user removals.
    """

    __tablename__ = "merchant_audit_log"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    merchant_id: Mapped[int] = mapped_column(Integer, ForeignKey("merchants.id"), nullable=False, index=True)
    actor_user_id: Mapped[int] = mapped_column(Integer, ForeignKey("users.id"), nullable=False)
    action: Mapped[str] = mapped_column(String(100), nullable=False, index=True)
    target_user_id: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("users.id"), nullable=True)
    target_role_id: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("roles.id"), nullable=True)
    metadata_: Mapped[Optional[dict]] = mapped_column("metadata", JSON, nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now(), index=True)

    actor: Mapped["User"] = relationship("User", foreign_keys=[actor_user_id], uselist=False)