from sqlalchemy.orm import Session
from model.student_info import Student
from schemas.student_info import StudentCreate, StudentUpdate,StudentDate, StudentResponse



#查询  查询学生信息（按编号、姓名、班级条件筛选）
#orm动态查询
def list_students(db: Session,id: str = None,name: str = None,class_name: str = None):
    # 已逻辑删除的学生
    query = db.query(Student).filter(Student.is_deleted == False)
    # 查询学生信息（支持按编号、姓名、班级等条件筛选）。
    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)
    # 执行查询并返回
    return query.all()


#2创建新的学生
def create_student(db: Session,student: StudentCreate):
    data = {}
    #遍历
    for field_name in student.model_fields:
        if field_name == "id":
            val = student.id
        elif field_name == "name":
            val = student.name
        elif field_name == "gender":
            val = student.gender
        elif field_name == "class_no":
            val = student.class_name
        elif field_name == "major":
            val = student.major
        elif field_name == "age":
            val = student.age
        elif field_name == "hometown":
            val = student.hometown
        else:
            val = None
        data[field_name] = val
    # 赋值给ORM
    db_student = Student(
        id=data["id"],
        name=data["name"],
        gender=data["gender"],
        class_name=data["class_name"],
        major=data.get("major"),
        age=data.get("age"),
        hometown=data.get("hometown")
    )
    db.add(db_student)
    db.commit()
    db.refresh(db_student)
    return db_student

# 获取特定学生信息
# 严格按照需求文档：GET /students/{id}，从URL路径中获取学生学号
def get_student(db: Session,id: str):
    # 查询：id字段等于url传过来的id
    student = db.query(Student).filter(Student.id == id,).first()
    if student is None:
        return None
    return student


# 更新学生信息 /students/{id}  id为学号
def update_student( db: Session,id: str, payload: StudentUpdate):
    # 根据学号查询学生
    student = db.query(Student).filter(Student.id == id).first()
    # 学生是否存在
    if student is None:
        return None
    if payload.name is not None:
        student.name = payload.name
    if payload.age is not None:
        student.age = payload.age
    if payload.class_name is not None:
        student.class_name = payload.class_name
    # 保存到数据库
    db.commit()
    db.refresh(student)
    # 返回更新后的学生
    return student


# 逻辑删除学生。逻辑上删除，实际上未删除
def delete_student(db: Session,id: str):
    # 根据学号查询
    student = db.query(Student).filter(Student.id == id, Student.is_deleted == False).first()
    # 判断学生是否存在
    if student is None:
        return None
    # 逻辑删除：把is_deleted改成True，不是真的删掉这条记录
    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"}