"""
动态HMAC密钥模型
用于存储用户特定的动态HMAC密钥
"""
from datetime import datetime
from sqlalchemy import Column, Integer, String, DateTime, Boolean, Text
from app.database import Base
from app.utils.timezone import beijing_now_naive


class DynamicHmacKey(Base):
    """动态HMAC密钥表
    
    用于存储用户登录后获取的动态HMAC密钥，
    该密钥用于后续请求的签名验证。
    """
    __tablename__ = "dynamic_hmac_keys"
    
    id = Column(Integer, primary_key=True, autoincrement=True, comment="主键ID")
    user_id = Column(Integer, nullable=False, comment="用户ID")
    hmac_key = Column(Text, nullable=False, comment="HMAC密钥(Base64编码)")
    machine_code = Column(String(128), nullable=False, comment="机器码")
    key_version = Column(Integer, default=1, comment="密钥版本")
    is_active = Column(Boolean, default=True, comment="是否激活")
    is_deleted = Column(Boolean, default=False, comment="是否删除")
    created_at = Column(DateTime, default=beijing_now_naive, comment="创建时间")
    updated_at = Column(DateTime, nullable=True, comment="更新时间")
    expired_at = Column(DateTime, nullable=True, comment="过期时间")
    
    def __repr__(self):
        return f"<DynamicHmacKey(id={self.id}, user_id={self.user_id}, key_version={self.key_version})>"

    def is_expired(self) -> bool:
        """检查密钥是否过期"""
        if self.expired_at:
            return beijing_now_naive() > self.expired_at
        return False