###
# multiplication_game.py
#
# author: Kristina Striegnitz
#
# version: 3/10/2010
#
# A GUI application that lets the user practice multiplication of
# numbers up too 20.
###

from Tkinter import *
import random


def check_solution(solution, n1, n2):
    """
    Checks whether the solution input by the user is the same as the
    correct solution. Returns the message string to be displayed to
    the user in the GUI.
    """
    user_sol = int(solution.get())
    real_sol = int(n1.get()) * int(n2.get())

    if user_sol == real_sol:
        return str(real_sol)+" is right. Well done!"
    else:
        return "Solution is "+str(real_sol)+". Try again."


def new_problem(n1, n2, solution, message):
    """
    Randomly generates a new multiplication problem (two new numbers)
    and displays it in the GUI.
    """
    n1.set(random.randint(0,20))
    n2.set(random.randint(0,20))
    solution.set("")
    message.set("")

    
def main():
    
    main_window = Tk()
    main_window.title("Test Window")
    main_window.geometry("500x100")

    # four frames stacked on top of each other
    frame1 = Frame(main_window)
    frame1.pack(side="top")
    frame2 = Frame(main_window)
    frame2.pack(side="top")
    frame3 = Frame(main_window)
    frame3.pack(side="top")
    frame4 = Frame(main_window)
    frame4.pack(side="top")

    # content of frame 1: multiplication problem and entry box for the
    # user to enter the solution
    n1 = StringVar()
    n1.set(random.randint(0,20))
    n1_label = Label(frame1, textvariable=n1)
    n1_label.pack(side="left")
    
    op = Label(frame1, text="x")
    op.pack(side="left")
    
    n2 = StringVar()
    n2.set(random.randint(0,20))
    n2_label = Label(frame1, textvariable=n2)
    n2_label.pack(side="left")
    
    eq = Label(frame1, text="=")
    eq.pack(side="left")

    solution = StringVar()
    solution_entry = Entry(frame1, width=5, textvariable=solution)
    solution_entry.pack(side="left")

    # content of frame 2: response message
    message_text = StringVar()
    message = Label(frame2, textvariable=message_text)
    message.pack()

    # content of frame 3: submit and next button
    submit_b = Button(frame3, text="Submit", command = lambda: message_text.set( check_solution(solution_entry, n1, n2)))
    submit_b.pack(side="left")

    next = Button(frame3, text="Next", command = lambda: new_problem(n1, n2, solution, message_text))
    next.pack(side="right")

    # content of frame 4: quit button
    quit_b = Button(frame4, text="Quit", command=main_window.destroy)
    quit_b.pack(side="right")

    main_window.mainloop()


main()