# api/stu_api.py
# 学生信息管理模块：接口层只负责 HTTP 出入参与响应组装，查库/校验/事务交给 dao.stu_dao
# 业务异常（NotFoundError / ConflictError）由 main.py 注册的全局处理器统一转成状态码

from typing import Optional

from fastapi import APIRouter, Depends, Query
from sqlalchemy.orm import Session

from dao import stu_dao
from database import get_db
from schemas.stu_schema import StuInfoCreate, StuInfoUpdate, StuInfoOut

router = APIRouter()


def _to_detail(stu) -> dict:
    """把学生实体组装成详情响应：基础字段 + 班级 / 顾问 / 成绩 / 就业信息。"""
    data = StuInfoOut.model_validate(stu).model_dump()

    # 班级信息
    data["cls"] = None
    if stu.cls:
        data["cls"] = {
            "id": stu.cls.id,
            "cls_start_date": stu.cls.cls_start_date.isoformat() if stu.cls.cls_start_date else None,
        }

    # 顾问信息
    data["advisor"] = {"id": stu.adv.id, "name": stu.adv.name} if stu.adv else None

    # 成绩列表（过滤已删除）
    data["scores"] = [
        {
            "exam_attempt": s.exam_attempt,
            "exam_score": s.exam_score,
            "score_level": s.score_level,
        }
        for s in stu.score
        if not s.is_deleted
    ]

    # 就业信息（一对一）
    data["employ"] = None
    if stu.stu_emp_mgmt and not stu.stu_emp_mgmt.is_deleted:
        e = stu.stu_emp_mgmt
        data["employ"] = {
            "emp_company": e.emp_company,
            "salary": e.salary,
            "emp_open_time": e.emp_open_time.isoformat() if e.emp_open_time else None,
            "send_offer_time": e.send_offer_time.isoformat() if e.send_offer_time else None,
        }

    return data


@router.get("", summary="分页查询学生列表")
def list_students(
    page: int = Query(1, ge=1, description="页码"),
    size: int = Query(10, ge=1, le=100, description="每页数量"),
    name: Optional[str] = Query(None, description="按姓名模糊查询"),
    cls_id: Optional[str] = Query(None, description="按班级编号过滤"),
    state: Optional[str] = Query(None, description="按状态过滤"),
    db: Session = Depends(get_db),
):
    """查询未删除的学生，支持分页和按姓名/班级/状态过滤。"""
    total, items = stu_dao.list_students(
        db, page=page, size=size, name=name, cls_id=cls_id, state=state
    )
    return {
        "total": total,
        "page": page,
        "size": size,
        "items": [StuInfoOut.model_validate(x) for x in items],
    }


@router.get("/{stu_id}", summary="查询单个学生详情")
def get_student(stu_id: str, db: Session = Depends(get_db)):
    """查询学生详情，并附带班级、顾问、成绩与就业信息。"""
    return _to_detail(stu_dao.assert_stu_alive(db, stu_id, "学生不存在或已删除"))


@router.post("", response_model=StuInfoOut, status_code=201, summary="新增学生")
def create_student(payload: StuInfoCreate, db: Session = Depends(get_db)):
    """新增学生（学号唯一、班级与顾问必须存在，由 DAO 校验）。"""
    return stu_dao.create_student(db, payload.model_dump())


@router.put("/{stu_id}", response_model=StuInfoOut, summary="更新学生信息")
def update_student(stu_id: str, payload: StuInfoUpdate, db: Session = Depends(get_db)):
    """按传入字段局部更新学生信息。"""
    return stu_dao.update_student(db, stu_id, payload.model_dump(exclude_unset=True))


@router.delete("/{stu_id}", summary="删除学生(软删除)")
def delete_student(stu_id: str, db: Session = Depends(get_db)):
    """软删除学生：仅置 is_deleted 标记，数据保留。"""
    stu_dao.soft_delete_student(db, stu_id)
    return {"message": "删除成功", "id": stu_id}