"""老师表（需求 2.5）。"""

from __future__ import annotations

from datetime import date

from sqlalchemy import Date, String
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.model.assoc import class_teachers
from app.model.base import Base, SoftDeleteMixin, TimestampMixin
from app.model.constants import GENDER_TEXT


class Teacher(Base, TimestampMixin, SoftDeleteMixin):
    __tablename__ = "teacher"
    __table_args__ = {"comment": "授课老师表"}

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    teacher_no: Mapped[str] = mapped_column(String(20), unique=True, nullable=False, comment="工号")
    name: Mapped[str] = mapped_column(String(30), nullable=False, index=True, comment="姓名")
    gender: Mapped[int] = mapped_column(default=1, nullable=False, comment="性别 1=男 2=女")
    phone: Mapped[str | None] = mapped_column(String(20), comment="手机号")
    email: Mapped[str | None] = mapped_column(String(60), comment="邮箱")
    title: Mapped[str | None] = mapped_column(String(30), comment="职称，如 讲师/高级讲师")
    subject: Mapped[str | None] = mapped_column(String(50), comment="授课方向，如 Java/前端/大数据")
    hire_date: Mapped[date | None] = mapped_column(Date, comment="入职时间")
    remark: Mapped[str | None] = mapped_column(String(255), comment="备注")

    # 带班信息：多对多
    classes: Mapped[list["Clazz"]] = relationship(  # noqa: F821
        secondary=class_teachers,
        back_populates="teachers",
        lazy="selectin",
    )

    # ---------------- 出参派生字段 ----------------
    @property
    def gender_text(self) -> str | None:
        return GENDER_TEXT.get(self.gender)

    @property
    def class_names(self) -> list[str]:
        return [c.name for c in self.classes if c.is_del == 0]

    @property
    def class_count(self) -> int:
        return len(self.class_names)