from pathlib import Path

from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session
from typing import List

from dao.cls_mgmt_dao import ClsMgmtDAO
from database import get_db
from scheme.cls_mgmt_scheme import ClsMgmtResponse, ClsMgmtCreate
router = APIRouter()

@router.get("/", response_model=List[ClsMgmtResponse])
# @router.get("/",response_model=ClsMgmtResponse)
async def get_classes(
    skip: int = Query(0, ge=0, description="跳过的记录数"),
    limit: int = Query(100, ge=1, le=200, description="返回的最大记录数"),
    db: Session = Depends(get_db)   # 依赖注入获得数据库会话
):
    """
    获取班级列表，支持分页
    """
    classes = ClsMgmtDAO.get_all(db, skip=skip, limit=limit)
    return classes   # FastAPI 自动根据 response_model 转换为 JSON

# @router.get("/{class_id}", response_model=ClsMgmtResponse)
# @router.get("/{class_id}")
# async def get_class(
#     class_id: str = Path(description="班级id:260814"),
#     db: Session = Depends(get_db)
# ):
#     """
#     根据班级 ID 获取详细信息
#     """
#     user = ClsMgmtDAO.get_by_id(db, class_id)
#     if not user:
#         raise HTTPException(status_code=404, detail="班级不存在")
#     return user

@router.get("/{class_id}",response_model=ClsMgmtResponse)  # ← 加这一行
async def get_class(
    class_id: str = Path(description="班级id:260814"),
    db: Session = Depends(get_db)
):
    """
    根据班级 ID 获取详细信息
    """
    cls = ClsMgmtDAO.get_by_id(db, class_id)
    if not cls:
        raise HTTPException(status_code=404, detail="班级不存在")
    return cls   # 直接返回 ORM 对象，FastAPI 自动转成 ClsMgmtResponse
# @router.get(
#     "/{class_id}",
#     response_model="ClsMgmtResponse",
#     summary="根据班级id获取详细信息"
# )
# async def get_class(
#     class_id: str = Path(description="班级id,例:260814"),
#     db: Session = Depends(get_db)
# ):
#     cls = ClsMgmtDAO.get_by_id(db, class_id)
#     if not cls:
#         raise HTTPException(status_code=404, detail="班级不存在")
#     return cls

# @router.post("/{class_id}")  # ← 加这一行
# async def add_class(
#     class_id: str = Path(description="班级id:260814"),
#     db: Session = Depends(get_db)
# ):
#     """
#     根据班级 ID 获取详细信息
#     """
#     cls = ClsMgmtDAO.get_by_id(db, class_id)
#     if not cls:
#         raise HTTPException(status_code=404, detail="班级不存在")
#     return cls

@router.post(
    "/add_class",
    response_model=ClsMgmtResponse
    # status_code=201,
    # summary="新增班级"
)
async def create_class(
    cls_data: ClsMgmtCreate,
    db: Session = Depends(get_db)
):
    """
    新增班级
    - 班级id自动生成：根据开课时间取后6位（如 2026-08-14 → 260814）
    - 先根据班级id验证是否已存在
    - 已存在 → 返回 400「班级已存在」
    - 不存在 → 新增班级
    """
    # 第一步：根据开课时间生成班级id
    class_id = ClsMgmtDAO.generate_class_id(cls_data.cls_start_date)
    # 第二步：根据班级id验证是否已存在
    if ClsMgmtDAO.exists(db, class_id):
        raise HTTPException(
            status_code=400,
            detail=f"班级已存在（班级id：{class_id}）"
        )
    # 第三步：不存在则新增
    new_cls = ClsMgmtDAO.create(db, cls_data)
    return new_cls

@router.delete(
    "/del_class/{class_id}",
    # response_model=ClsMgmtResponse
    # status_code=201,
    # summary="新增班级"
)
async def del_class(
    class_id: str = Path(description="班级id:260814"),
    db: Session = Depends(get_db)
):
    """
    删除班级
    """
    print(class_id)
    del_cls = ClsMgmtDAO.delete_class(db, class_id)
    return del_cls

@router.put(
    "/update_class/{class_id}",
    response_model=ClsMgmtResponse
    # status_code=201,
    # summary="新增班级"
)
async def update_class(
    cls_data: ClsMgmtCreate,
    class_id: str = Path(description="班级id:260814"),

    db: Session = Depends(get_db)
):
    """
    根据班级ID修改班主任和授课老师信息
    """
    update_cls = ClsMgmtDAO.update_cls(db, cls_data,class_id)
    return update_cls