"""customer_relation 客户-投顾关系表 ORM 模型。

同时服务于：
- 投顾工作台（advisor）：签约状态 已分配/已签约/已结束，工作台为唯一写入方；
- 记忆/client_agent 模块：读取客户与投顾的当前或历史关系。
"""

from __future__ import annotations

from datetime import datetime

from sqlalchemy import BigInteger, CheckConstraint, DateTime, String, func
from sqlalchemy.orm import Mapped, mapped_column

from common.common_const import (
    CUSTOMER_REL_STATUS_UNSIGNED,
)
from model.base import Base


class CustomerRelation(Base):
    __tablename__ = "customer_relation"
    __table_args__ = (
        CheckConstraint(
            "status IN ('已分配', '已签约', '已结束')",
            name="ck_customer_relation_status",
        ),
        {"comment": "客户-投顾关系表（状态驱动：签约后投顾Agent方案正式触达客户）"},
    )

    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
    customer_id: Mapped[int] = mapped_column(BigInteger, nullable=False)
    advisor_id: Mapped[int] = mapped_column(BigInteger, nullable=False)
    assign_time: Mapped[datetime] = mapped_column(
        DateTime, nullable=False, server_default=func.now()
    )
    signed_time: Mapped[datetime | None] = mapped_column(DateTime)
    end_time: Mapped[datetime | None] = mapped_column(DateTime)
    status: Mapped[str] = mapped_column(
        String(16), nullable=False, server_default=CUSTOMER_REL_STATUS_UNSIGNED
    )
    reason: Mapped[str | None] = mapped_column(String(128))