class GmailAccount(Base, TimestampMixin):
    __tablename__ = "gmail_accounts"
    id = Column(Integer, primary_key=True)
    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True)
    email = Column(String(320), nullable=False)
    display_name = Column(String(200), default="")
    status = Column(String(30), default="pending")  # pending|authorized|expired|revoked|error
    sending_method = Column(String(20), default="api")  # api|smtp
    auth_provider = Column(String(60), default="google")
    google_user_id = Column(String(120), default="")
    # Per-account config (administrator-configurable)
    daily_limit = Column(Integer, default=200)          # provider/configured daily cap
    campaign_limit = Column(Integer, default=200)       # per-account per-campaign cap
    sends_today = Column(Integer, default=0)
    last_send_date = Column(DateTime(timezone=True))
    cooldown_until = Column(DateTime(timezone=True))
    last_success_at = Column(DateTime(timezone=True))
    last_error = Column(Text, default="")
    error_count = Column(Integer, default=0)
    token_expiry = Column(DateTime(timezone=True))
    # Imported client config reference (optional; may use server-level config)
    oauth_config_id = Column(Integer, ForeignKey("oauth_client_configs.id", ondelete="SET NULL"))
    # Encrypted SMTP OAuth2 credentials mirror (kept in oauth_tokens; this is metadata only)
    is_active = Column(Boolean, default=True, nullable=False)
    revoked_by_user = Column(Boolean, default=False)
    revoked_at = Column(DateTime(timezone=True))

    user = relationship("User", back_populates="gmail_accounts")
    oauth_token = relationship("OAuthToken", back_populates="account", uselist=False,
                               cascade="all, delete-orphan")
    oauth_config = relationship("OAuthClientConfig")

    __table_args__ = (UniqueConstraint("user_id", "email", name="uq_gmail_account_user_email"),
                      Index("ix_gmail_status", "status"),)

    def usage_summary(self):
        return {"daily_limit": self.daily_limit, "sends_today": self.sends_today,
                "campaign_limit": self.campaign_limit,
                "last_success_at": self.last_success_at.isoformat() if self.last_success_at else None,
                "errors": self.error_count, "status": self.status}