from tkinter import *
from tkinter import messagebox
from decimal import *


class TipCalculatorInterface(Tk):
    def __init__(self, title):
        super().__init__()

        self.title(title)
        self.resizable(width=False, height=False)

        self.protocol("WM_DELETE_WINDOW", self.on_closing())

        self.main_frame = Frame(self)

        self.main_frame.grid(padx=14, pady=14)

        self.create_widgets()

        self.total_tip = 0

    def create_widgets(self):

        self.amount_label = Label(self.main_frame, text='Montant')
        self.amount_var = StringVar('')
        self.amount_entry = Entry(self.main_frame, textvariable=self.amount_var)
        self.amount_entry.focus()
        self.amount_label.grid(row=0, column=0, padx=5, pady=5, sticky=E)
        self.amount_entry.grid(row=0, column=1, padx=5, pady=5, sticky=W)

        self.tip_percentage_label = Label(self.main_frame, text='15%')
        self.tip_percentage_scale = Scale(
            self.main_frame,
            from_=0,
            to=100,
            orient=HORIZONTAL,
            showvalue=False,
            troughcolor='white',
            command=self.update_tip_percentage_label)
        self.tip_percentage_scale.set(15)
        self.tip_percentage_label.grid(
            row=1, column=0, padx=5, pady=5, sticky=E)
        self.tip_percentage_scale.grid(
            row=1, column=1, padx=5, pady=5, sticky=E + W)

        self.tip_label = Label(self.main_frame, text='Pourboire')
        self.tip_var = StringVar('')
        self.tip_entry = Entry(
            self.main_frame, state='readonly', textvariable=self.tip_var)
        self.tip_label.grid(row=2, column=0, padx=5, pady=5, sticky=E)
        self.tip_entry.grid(row=2, column=1, padx=5, pady=5, sticky=W)

        self.total_label = Label(self.main_frame, text='Total')
        self.total_var = StringVar('')
        self.total_entry = Entry(
            self.main_frame, state='readonly', textvariable=self.total_var)
        self.total_label.grid(row=3, column=0, padx=5, pady=5, sticky=E)
        self.total_entry.grid(row=3, column=1, padx=5, pady=5, sticky=W)

        self.calculate_button = Button(
            self.main_frame, text='Calculer', command=self.calculate_total)
        self.calculate_button.grid(
            row=4, column=1, padx=5, pady=5, sticky=E + W)



    def update_tip_percentage_label(self, value):
        self.tip_percentage_label['text'] = '{}%'.format(int(float(value)))

    def calculate_total(self):
        try:
            amount = Decimal(self.amount_var.get())
            tip = amount * Decimal(self.tip_percentage_scale.get()) / Decimal(100)
            self.total_tip += tip
            print(self.total_tip)
            total = amount + tip
            self.tip_var.set('{} $'.format(tip))
            self.total_var.set('{} $'.format(total))
        except InvalidOperation:
            self.amount_var.set('Entrez un montant valide')
            self.amount_entry.icursor(END)

    def on_closing(self):
        messagebox.showinfo('Here is the message')


if __name__ == '__main__':
    TipCalculatorInterface('Calculateur de Pourboire').mainloop()