from fastapi import APIRouter, Depends, HTTPException
from pymysql import IntegrityError
from sqlalchemy.orm import Session
from typing import List
from model.classes_model import Classes
from dao.student_dao import update_student
from database import get_db
from model.student_info import Student
from schemas.student_info import StudentCreate, StudentUpdate, StudentResponse,student_date

router = APIRouter(prefix="/students", tags=["学生基本信息"])

# 1. 查询
@router.get("", response_model=List[StudentResponse], summary="查询学生")
def list_students(
        id: str = None,
        name: str = None,
        class_name: str = None,
        db: Session = Depends(get_db)
):
    query = db.query(Student).filter(Student.is_deleted == False)
    if id:
        query = query.filter(Student.id == id)
    if name:
        query = query.filter(Student.name.like(f"%{name}%"))
    if class_name:
        query = query.filter(Student.class_name == class_name)
    return query.all()


# 2. 创建
@router.post("", response_model=StudentResponse, summary="创建新学生")
def create_student(student: StudentCreate, db: Session = Depends(get_db)):
    # 调用校验函数 如果入学日期存在，就把它变成字符串；如果不存在，就赋值为空
    enroll_str = student.enrollment_date.strftime("%Y-%m-%d") if student.enrollment_date else None
    grad_str = student.graduation_date.strftime("%Y-%m-%d") if student.graduation_date else None
    date_check_result = student_date(enroll_str, grad_str)

    #如果不存在，直接抛出异常中断请求
    if date_check_result != "时间校验通过":
        raise HTTPException(status_code=400, detail=date_check_result)
    #  检查学号是否已存在
    exist = db.query(Student).filter(Student.id == student.id).first()
    if exist:
        raise HTTPException(status_code=400, detail=f"学号 {student.id} 已存在")

    # 不存在的班级导致外键约束报错
    class_exists = db.query(Classes).filter(
        Classes.class_name == student.class_name,
    ).first()
    if not class_exists:
        raise HTTPException(status_code=400,detail=f"班级 '{student.class_name}' 不存在，请检查输入是否正确！")

    # 3. 构建数据库模型对象 一个个赋值
    db_student = Student(
        id=student.id,
        name=student.name,
        gender=student.gender,
        class_name=student.class_name,
        age=student.age,
        hometown=student.hometown,
        graduate_school=student.graduate_school,
        major=student.major,
        education=student.education,
        enrollment_date=student.enrollment_date,
        graduation_date=student.graduation_date,
        status=student.status,
        is_deleted=False
    )
    db.add(db_student)
    db.commit()
    db.refresh(db_student)
    return db_student #返回响应


# 3. 详情
@router.get("/{id}", response_model=StudentResponse, summary="获取特定学生信息")
def get_student(id: str, db: Session = Depends(get_db)):
    student = db.query(Student).filter(
        Student.id == id,
        Student.is_deleted == False
    ).first()
    if student is None:
        raise HTTPException(status_code=404, detail="学生不存在或已删除")
    return student


# 4. 更新
@router.put("/{id}", response_model=StudentResponse, summary="更新学生信息")
def api_update_student(id: str, payload: StudentUpdate, db: Session = Depends(get_db)):
    try:
        student = update_student(db, id, payload)
        if student is None:
            raise HTTPException(status_code=404, detail="学生不存在或已删除")
        return student
    except IntegrityError:
        db.rollback()
        raise HTTPException(status_code=400, detail="更新失败：指定的班级不存在，请先创建对应班级！")



# 5. 逻辑删除
@router.delete("/{id}", summary="逻辑删除学生")
def delete_student(id: str, db: Session = Depends(get_db)):
    student = db.query(Student).filter(
        Student.id == id,
        Student.is_deleted == False
    ).first()
    if student is None:
        raise HTTPException(status_code=404, detail="学生不存在或已删除")
    student.is_deleted = True
    db.commit()
    return {"message": f"学生 {id} 已逻辑删除，数据仍保留在库中"}