import sys
import os

sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

from fdm.solver import solve
from fdm.visualizer import visualize_fdm


def print_header():
    print("=" * 38)
    print("  Heat Equation — FDM Solver")
    print("  ∂T/∂t = α ∂²T/∂x²")
    print("=" * 38)


def main_menu():
    print("\nInitializing solver...")
    print("Ready.\n")

    T, x_vals, t_vals = None, None, None

    while True:
        print("\n" + "-" * 30)
        print("         MAIN MENU")
        print("-" * 30)
        print("1. Risolvi")
        print("2. Visualizza")
        print("0. Esci")
        print("-" * 30)

        choice = input("Select an option (0-2): ").strip()

        if choice == "1":
            T, x_vals, t_vals = solve()
            print(f"Soluzione completata. Shape T: {T.shape}")
            print(f"T range: [{T.min():.2f}, {T.max():.2f}] °C")

        elif choice == "2":
            if T is None:
                print("Eseguire prima l'opzione 1.")
            else:
                visualize_fdm(T, x_vals, t_vals)

        elif choice == "0":
            print("Uscita.")
            sys.exit(0)

        else:
            print("Scelta non valida.")


if __name__ == "__main__":
    print_header()
    main_menu()