# 学生管理系统
import os.path
import sys

students = []


# 存档
def save():
    with open("record.txt", "w", encoding="utf8") as f:
        count = 0
        for s in students:
            f.write(f"{s['student_id']}\t{s['student_name']}\t{s['gender']}\t{s['class_name']}\n")
            count += 1
        print(f"[存档成功] | 共存档 {count} 条内容")


# 读档
def load():
    # 如果存档文件不存在, 则跳过读档
    if not os.path.exists("record.txt"):
        return
    # 读档时要先清理旧数据
    count = 0
    global students
    students = []
    with open("record.txt", "r", encoding="utf8") as f:
        for line in f:
            line = line.strip()
            tokens = line.split("\t")
            if len(tokens) != 4:
                print(f"当前行格式有误: line = {line}")
                continue
            count += 1
            student = {
                "student_id": tokens[0],
                "student_name": tokens[1],
                "gender": tokens[2],
                "class_name": tokens[3]
            }
            students.append(student)
    print(f"[读档成功] | 共读取 {count} 条内容")


def menu():
    print("1. 新增学生")
    print("2. 显示学生")
    print("3. 查找学生")
    print("4. 删除学生")
    print("0. 退出程序")
    choice = input("请输入您的选项: ")
    return choice


def add_student():
    # pass
    print("[新增学生] | 开始")
    student_id = input("请输入学生的学号: ")
    student_name = input("请输入学生的姓名: ")
    gender = input("请输入学生的性别: ")
    if gender not in ("男", "女"):
        print("输入的性别有误")
        return
    class_name = input("请输入学生的班级: ")
    student = {
        "student_id": student_id,
        "student_name": student_name,
        "gender": gender,
        "class_name": class_name
    }
    global students
    students.append(student)
    # 保存学生信息
    save()
    print("[新增学生] | 结束")


def show_all_students():
    # pass
    print("[显示学生] | 开始")
    for student in students:
        print(f"student = {student['student_id']}\t{student['student_name']}\t"
              f"{student['gender']}\t{student['class_name']}")
    print("[显示学生] | 结束")


def find_student():
    # pass
    print("[查找学生] | 开始")
    name = input("请输入要查找学生的姓名: ")
    for student in students:
        if name in student['student_name']:
            print(f"student = {student['student_id']}\t{student['student_name']}\t"
                  f"{student['gender']}\t{student['class_name']}")
    print("[查找学生] | 结束")


def delete_student():
    # pass
    print("[删除学生] | 开始")
    name = input("请输入要删除学生的姓名: ")
    global students
    # 有 Bug -> 忌讳一边遍历, 一边删除
    temp = []
    for student in students:
        if name in student['student_name']:
            temp.append(student)
    for s in temp:
        students.remove(s)
    # 保存学生信息
    save()
    print("[删除学生] | 结束")


def main():
    """
    入口函数
    """
    load()
    print("---------------------------------")
    print("-----------学生管理系统------------")
    print("---------------------------------")
    while True:
        # 打印菜单
        choice = menu()
        if choice == '1':
            # 新增学生
            add_student()
        elif choice == '2':
            # 显示所有学生
            show_all_students()
        elif choice == '3':
            # 查找指定学生
            find_student()
        elif choice == '4':
            # 删除学生
            delete_student()
        elif choice == '0':
            # 退出程序
            print("退出程序")
            sys.exit(0)
        else:
            print("输入内容有误, 重新输入")
            # continue


main()