student_example

'''


This example allows the user to search for students grades and also 
allows the users to add a student, view report cards for a student,
and add a mark for a student 
FUNCTION 1 : print report cards
    This function needs to print report cards for all students
    This function needs to print report card for a student
FUNCTION 2: add a new student
FUNCION 3: add mark for a student
'''
# Create a list of students
# Students - Need key value pairs
students = [["Ben", {"Maths": 67, "English": 78, "Science": 72}],
            ["Mark", {"Maths" : 56, "Art" : 64, "History": 39, "Geography": 55}],
            ["Paul", {"English": 66, "History": 88}]                  
            ]
grades = ((0, "Fail"), (50, "D"), (60, "C"), (70, "B"), (80, "A"), (101, "CHEAT!"))

def print_report_card(student_name = None):   # None inside an argument makes it optional
    for student in students:
        print("Student Name : ", student[0])
        if (student[0] == student_name) or (student_name == None):
            print("Report card for student", student[0])
            for subject, mark in student[1].items():
                print("Subject", subject)
                print("Mark", mark)
                for grade in grades:
                    if mark < grade[0]:
                        print(subject, ";", prev_grade)
                        break
                    prev_grade = grade[1]   #grade[1] is letter grade or Fail
                    
#print_report_card("Paul")  
#print_report_card()   

def add_student(student_name):
    global students 
    for student in students:
        if student[0] == student_name:
            print("Student already exists!")
    student.append([student_name, {}])
    return "Student added successfully!"
    
def add_mark(student_name, subject, mark): 
    global students
    for student in students:
        if student[0] == student_name:
            if subject in student[1].keys():
                print(student_name, "already has a mark for ", subject)
                user_input = input("Do you want to overwrite Y/N ?")
                if user_input == "Y" or user_input == "y":
                    student[1][subject] = mark
                    return "Students mark was updated"
                else:
                    return "Students mark was not updated"
            else: 
                student[1][subject] = mark
                return "Student's mark was added"    
    return "Student not found"

while True:
    print("Welcome to the Student Database")
    print("What can I help you with?")
    print("Enter 1 to view all report cards")
    print("Enter 2 to view the report card for a student")
    print("Enter 3 to add a student")
    print("Enter 4 to add a mark for a student")
    print("Enter 5 to exit")
    
    try:
        user_choice = int(input("Choice: "))
    except ValueError:
        print("That's not a number I recognize")
        user_choice = 0
        
    if user_choice == 1:
        print_report_card()
    elif user_choice == 2:
        enter_student = input("Which Student?")
        print_report_card(enter_student)
    elif user_choice == 3:
        enter_student = input("Student Name?")
        print(add_student(enter_student))
    elif user_choice == 4:
        enter_student = input("Student Name?")
        enter_subject = input("Subject?")
        num_error = True
        while num_error:
            num_error = False
            try: 
                enter_mark = int(input("Mark?"))
            except ValueError:
                print("I don't recognize that as a number")
                num_error = True
        print(add_mark(enter_student, enter_subject, enter_mark))
    elif user_choice == 5:
        break
    else:
        print("Unknown choice")
    input("Press enter to continue")
print("Thanks for using the Student Database")