import json
# students = {
#     '103': {'name': 'ali', 'grade':{}},
#     '104': {'name': 'ali', 'grade':{'math': 18, 'chimi': 12}},
#     '105': {'name': 'ali', 'grade':{'math': 18, 'chimi': 12}},
# }

class SchoolSystem:
    def __init__(self) -> None:
        self.students = self.get_data()
        print('school system is running')    
    
    def show_menu(self):
        self.set_data()
        print('\n'*3)
        print('='*50)
        print('1- Show Students list')
        print('2- Show a Student grade')
        print('3- Add Student')
        print('4- Assign Grade')
        print('5- Save')
        print('6- Save and Exit')

    def add_student(self):
        name = input('name: ')
        id = len(self.students) + 1
        self.students.update({
            str(id): {'name': name, 'grade':dict()}
        })
    
    def show_student_list(self):
        if not self.students:
            print('there is no student')
        else:
            for id in self.students:
                print(f"{id}- {self.students[id]['name']}")

    def show_grade(self):
        self.show_student_list()
        while True:
            id = input('which id: ')
            if id in self.students.keys():
                break
            else:
                print('id is not valid')
                
        print(f"{id}- {self.students[id]['name'].upper()}")
        
        if not self.students[id]['grade']:
            print('there is no grade')
        else:
            for course_name in self.students[id]['grade']:
                print(f"\t{course_name.capitalize()} {self.students[id]['grade'][course_name]}")

    
    def get_data(self):
        try:
            with open('school_data.json', 'r') as f:
                return json.load(f)
        except:
            return dict()
    
    def set_data(self):
        data = self.students
        with open('school_data.json', 'w') as f:
            json.dump(data, f)