import tkinter as tk
from tkinter import messagebox
from expression import npi2tree


def ajouter(val):
    entree.insert(tk.END, val + " ")


def calculer():
    try:
        texte = entree.get()
        liste = texte.split()
        arbre = npi2tree(liste)
        resultat.config(text="Résultat : " + str(arbre.evalue()))
    except:
        messagebox.showerror("Erreur", "Expression invalide")


def effacer():
    entree.delete(0, tk.END)
    resultat.config(text="")


fenetre = tk.Tk()
fenetre.title("Calculatrice NPI")
fenetre.geometry("500x600")

entree = tk.Entry(fenetre, width=35, font=("Arial", 18))
entree.pack(pady=20)

frame = tk.Frame(fenetre)
frame.pack()

chiffres = ["7", "8", "9",
            "4", "5", "6",
            "1", "2", "3",
            "0"]

i = 0
for c in chiffres:
    b = tk.Button(frame,
                  text=c,
                  width=6,
                  height=2,
                  font=("Arial", 16),
                  command=lambda x=c: ajouter(x))
    b.grid(row=i//3, column=i%3, padx=5, pady=5)
    i += 1

plus = tk.Button(frame, text="+", width=6, height=2,
                 font=("Arial", 16),
                 command=lambda: ajouter("+"))
plus.grid(row=0, column=3, padx=5, pady=5)

fois = tk.Button(frame, text="*", width=6, height=2,
                 font=("Arial", 16),
                 command=lambda: ajouter("*"))
fois.grid(row=1, column=3, padx=5, pady=5)

btn_calc = tk.Button(fenetre, text="Calculer",
                     font=("Arial", 16), height=2,
                     command=calculer)
btn_calc.pack(pady=10)

btn_clear = tk.Button(fenetre, text="Effacer",
                      font=("Arial", 16), height=2,
                      command=effacer)
btn_clear.pack(pady=5)

resultat = tk.Label(fenetre, text="", font=("Arial", 16), fg="red")
resultat.pack(pady=20)

fenetre.mainloop()