'''
Kyle Willett
ITMD 513
HW 12 - GUI - Main program file
Purpose: Models a change calculator and handles most if not all error cases.  Graphical input used.
'''
from tkinter import *
import tkinter.messagebox


window = Tk()
window.title("Change Counter")
window.geometry('600x400')
window.configure(background = "light yellow");

instructions = Label(window, text="Enter the number of each coin type and hit, compute:")
instructions.grid(column = 1, row = 0)

#Each coin is handled, first a label for coin name, a text entry box, a label for value, and a value box.
quarters_label = Label(window ,text = "Quarters:").grid(row = 1,column = 0)
quarters_entry_box = Entry(window)
quarters_entry_box.grid(row = 1,column = 1)
quarters_label2 = Label(window, text="Quarter Value: $").grid(row = 1, column = 2)
quarters_value = Label(window, text="0.00", borderwidth=2, relief="solid")
quarters_value.grid(row=1, column = 3)

dimes_label = Label(window ,text = "Dimes:").grid(row = 2,column = 0)
dimes_entry_box = Entry(window)
dimes_entry_box.grid(row = 2,column = 1)
dimes_label2 = Label(window, text="Dime Value: $").grid(row = 2, column = 2)
dimes_value = Label(window, text="0.00", borderwidth=2, relief="solid")
dimes_value.grid(row=2, column = 3)

Nickels_label = Label(window ,text = "Nickels:").grid(row = 3,column = 0)
Nickels_entry_box = Entry(window)
Nickels_entry_box.grid(row = 3,column = 1)
Nickles_label2 = Label(window, text="Nickel Value: $").grid(row = 3, column = 2)
Nickles_value = Label(window, text="0.00", borderwidth=2, relief="solid")
Nickles_value.grid(row=3, column = 3)

Pennies_label = Label(window ,text = "Pennies:").grid(row = 4,column = 0)
Pennies_entry_box = Entry(window)
Pennies_entry_box.grid(row = 4,column = 1)
Pennies_label2 = Label(window, text="Pennies Value: $").grid(row = 4, column = 2)
Pennies_value = Label(window, text="0.00", borderwidth=2, relief="solid")
Pennies_value.grid(row=4, column = 3)

half_dollars_label = Label(window ,text = "Half Dollars:").grid(row = 5,column = 0)
half_dollars_entry_box = Entry(window)
half_dollars_entry_box.grid(row = 5,column = 1)
half_dollars_label2 = Label(window, text="Half Dollar Value: $").grid(row = 5, column = 2)
half_dollars_value = Label(window, text="0.00", borderwidth=2, relief="solid")
half_dollars_value.grid(row=5, column = 3)

dollar_coins_label = Label(window ,text = "Dollar Coins:").grid(row = 6,column = 0)
dollar_coins_entry_box = Entry(window)
dollar_coins_entry_box.grid(row = 6,column = 1)
dollar_coins_label2 = Label(window, text="Dollar coin Value: $").grid(row = 6, column = 2)
dollar_coins_value = Label(window, text="0.00", borderwidth=2, relief="solid")
dollar_coins_value.grid(row=6, column = 3)

#Total label and compute button
total_label = Label(window, text="Total Change value: $").grid(row=7, column = 2)
total_value_label = Label(window, text="0.00", borderwidth=4, relief="solid")
total_value_label.grid(row=7, column = 3)

#calculate Function
def calculate():
    
    #Check for empty boxes, abort if any found
    #source on how to do: https://stackoverflow.com/questions/15455113/tkinter-check-if-entry-box-is-empty
    if len(quarters_entry_box.get()) == 0:
        tkinter.messagebox.showwarning("Warning", "A text field is blank, please enter 0 for all blank text fields")
        return
    if len(dimes_entry_box.get()) == 0:
        tkinter.messagebox.showwarning("Warning", "A text field is blank, please enter 0 for all blank text fields")
        return
    if len(Nickels_entry_box.get()) == 0:
        tkinter.messagebox.showwarning("Warning", "A text field is blank, please enter 0 for all blank text fields")
        return
    if len(Pennies_entry_box.get()) == 0:
        tkinter.messagebox.showwarning("Warning", "A text field is blank, please enter 0 for all blank text fields")
        return
    if len(half_dollars_entry_box.get()) == 0:
        tkinter.messagebox.showwarning("Warning", "A text field is blank, please enter 0 for all blank text fields")
        return
    if len(dollar_coins_entry_box.get()) == 0:
        tkinter.messagebox.showwarning("Warning", "A text field is blank, please enter 0 for all blank text fields")
        return
    
    #Check if integer values, abort if non integer values found
    #Source on how to do https://docs.python.org/3.7/tutorial/errors.html
    try:
        quarter_val = int(quarters_entry_box.get())
    except ValueError:
        tkinter.messagebox.showwarning("Warning", "Integer data type expected")
        return
    
    try:
        dime_val = int(dimes_entry_box.get())
    except ValueError:
        tkinter.messagebox.showwarning("Warning", "Integer data type expected")
        return
    
    try:
        nickel_val = int(Nickels_entry_box.get())
    except ValueError:
        tkinter.messagebox.showwarning("Warning", "Integer data type expected")
        return
    
    try:
        pennies_val = int(Pennies_entry_box.get())
    except ValueError:
        tkinter.messagebox.showwarning("Warning", "Integer data type expected")
        return
    
    try:
        half_dollar_val = int(half_dollars_entry_box.get())
    except ValueError:
        tkinter.messagebox.showwarning("Warning", "Integer data type expected")
        return
    
    try:
        dollar_coin_val = int(dollar_coins_entry_box.get())
    except ValueError:
        tkinter.messagebox.showwarning("Warning", "Integer data type expected")
        return
    
    #Check if values are negative and abort if any are.
    if quarter_val < 0:
        tkinter.messagebox.showwarning("Warning", "Values must be positive integers")
        return
    if dime_val < 0:
        tkinter.messagebox.showwarning("Warning", "Values must be positive integers")
        return
    if nickel_val < 0:
        tkinter.messagebox.showwarning("Warning", "Values must be positive integers")
        return
    if pennies_val < 0:
        tkinter.messagebox.showwarning("Warning", "Values must be positive integers")
        return
    if half_dollar_val < 0:
        tkinter.messagebox.showwarning("Warning", "Values must be positive integers")
        return
    if dollar_coin_val < 0:
        tkinter.messagebox.showwarning("Warning", "Values must be positive integers")
        return
    
    quarterAmount = quarter_val * 0.25
    dimeAmmount = dime_val * 0.10
    nickelAmmount = nickel_val * 0.05
    penniesAmmount = pennies_val * 0.01
    halfDollarAmmount = half_dollar_val * 0.5
    dollarCoinAmmount = dollar_coin_val * 1
    
    quarters_value.config(text=quarterAmount)
    dimes_value.config(text=dimeAmmount)
    Nickles_value.config(text=nickelAmmount)
    Pennies_value.config(text=penniesAmmount)
    half_dollars_value.config(text=halfDollarAmmount)
    dollar_coins_value.config(text=dollarCoinAmmount)
    
    totalSum = quarterAmount + dimeAmmount + nickelAmmount + penniesAmmount + halfDollarAmmount + dollarCoinAmmount
    
    total_value_label.config(text=totalSum)

btn = Button(window, text="Compute", command=calculate, borderwidth=4, relief="solid").grid(row=7, column= 1)


window.mainloop()