from datetime import datetime
from typing import Any

from sqlalchemy import DateTime, Integer
from sqlalchemy.orm import Mapped, mapped_column
from sqlalchemy.sql import func

from app.core.database import Base


class BaseModel(Base):
    """
    所有数据库模型的基类
    包含通用字段：id, created_at, updated_at
    """

    __abstract__ = True

    id: Mapped[int] = mapped_column(Integer, primary_key=True, index=True, autoincrement=True)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), 
        server_default=func.now(),
        nullable=False,
    )
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        server_default=func.now(),
        onupdate=func.now(),
        nullable=False,
    )

    def dict(self) -> dict[str, Any]:
        """
        将模型转换为字典
        """
        return {
            column.name: getattr(self, column.name)
            for column in self.__table__.columns
        }