"""数据脱敏规则模型 — 定义脱敏规则的存储结构。"""
from sqlalchemy import Column, Integer, String, Text, Boolean, DateTime, ForeignKey, func, UniqueConstraint

from app.core.database import Base


class MaskingRule(Base):
    """数据脱敏规则，用于动态脱敏查询结果。

    通过组合 (instance_id, database, table_name, column_name) 唯一确定一条规则。
    """

    __tablename__ = "masking_rules"

    id = Column(Integer, primary_key=True, autoincrement=True)
    instance_id = Column(Integer, ForeignKey("instances.id"), nullable=False)
    database = Column(String(100), nullable=False)
    table_name = Column(String(100), nullable=False)
    column_name = Column(String(100), nullable=False)
    mask_type = Column(String(30), nullable=False)  # full / partial / hash / truncate / regex
    mask_config = Column(Text, nullable=True)  # JSON 配置
    is_enabled = Column(Boolean, default=True)
    created_at = Column(DateTime, server_default=func.now())
    updated_at = Column(DateTime, server_default=func.now(), onupdate=func.now())

    __table_args__ = (
        UniqueConstraint(
            "instance_id", "database", "table_name", "column_name",
            name="uk_masking_rule_col"
        ),
    )