test二轮完成的版本，并入了浩钦的班级模块

dao/wl_class_dao.py

@@ -0,0 +1,94 @@
+from sqlalchemy.orm import Session
+from model.wl_class_model import Class_
+from model.wl_student_model import Student
+from fastapi import HTTPException
+
+# 老师模块加入后解除注释
+# from model.teacher import WlTeacher
+
+
+# 1. 新增班级
+def create_class(db: Session, class_data: dict):
+    new_class = Class_(**class_data)
+    db.add(new_class)
+    db.commit()
+    db.refresh(new_class)
+    return new_class
+
+
+# 2. 查询班级列表（你的亮点：查出了班主任和授课老师）
+def get_classes(db: Session, skip: int = 0, limit: int = 100):
+    # 先查出所有没被删除的班级
+    class_list = db.query(Class_).filter(Class_.is_deleted == 0).offset(skip).limit(limit).all()
+    #下面的部分等导入老师模块后解除注释
+    # # 循环每个班级，去老师表里找对应的老师
+    # for c in class_list:
+    #     # 找班主任（role是"班主任"的第一个老师）
+    #     head_teacher = db.query(WlTeacher).filter(
+    #         WlTeacher.class_id == c.class_id,
+    #         WlTeacher.role == "班主任"
+    #     ).first()
+    #
+    #     # 找授课老师（可能有多个，用逗号拼起来）
+    #     course_teachers = db.query(WlTeacher).filter(
+    #         WlTeacher.class_id == c.class_id,
+    #         WlTeacher.role == "任课"
+    #     ).all()
+    #
+    #     # 把查到的名字塞给班级对象，方便传给前端
+    #     c.head_teacher_name = head_teacher.t_name if head_teacher else "暂无"
+    #     # 下面这两行是初学者常用的拼接字符串写法
+    #     if course_teachers:
+    #         names = []
+    #         for t in course_teachers:
+    #             names.append(t.t_name)
+    #         c.course_teacher_names = "，".join(names)
+    #     else:
+    #         c.course_teacher_names = "暂无"
+
+    return class_list
+
+
+# 3. 根据ID查班级
+def get_class_by_id(db: Session, class_id: int):
+    return db.query(Class_).filter(Class_.class_id == class_id, Class_.is_deleted == 0).first()
+
+
+# 4. 修改班级信息
+def update_class(db: Session, class_id: int, class_data: dict):
+    db_class = get_class_by_id(db, class_id)
+    if not db_class:
+        return None
+
+    # 前端传了什么，就改什么（防止把没传的字段改成空值）
+    for key, value in class_data.items():
+        setattr(db_class, key, value)
+
+    db.commit()
+    db.refresh(db_class)
+    return db_class
+
+
+# 5. 逻辑删除班级（你的亮点：安全检查）
+def delete_class(db: Session, class_id: int):
+    db_class = get_class_by_id(db, class_id)
+    if not db_class:
+        return {"code": 404, "msg": "班级不存在"}
+
+    # 检查1：班里还有学生吗？（只要有1个，就不给删）
+    student = db.query(Student).filter(
+        Student.class_id == class_id,
+        Student.is_deleted == 0
+    ).first()
+    if student:
+        raise HTTPException(status_code=400, detail="该班级还有学生，不能删除！")
+    #导入老师模块后解除注释
+    # 检查2：班里还有老师吗？
+    # teacher = db.query(WlTeacher).filter(WlTeacher.class_id == class_id).first()
+    # if teacher:
+    #     return {"code": 400, "msg": "该班级还有老师，不能删除！"}
+
+    # 检查通过，开始逻辑删除（贴个已删除标签）
+    db_class.is_deleted = 1
+    db.commit()
+    return {"code": 200, "msg": "班级删除成功"}