functions.py

from body import Customer, Product, Order, Admin, products, orders
from storage import save_customers_to_file, load_customers_from_file
from enum import Enum
from gui import load_products, EShopGUI

import json
import sys

customers = load_customers_from_file()


def load_products_from_file(filename="products.json"):
    try:
        with open(filename, "r") as file:
            data = json.load(file)
            for item in data:
                product = Product(
                    name=item["name"],
                    brand=item["brand"],
                    amount=item["amount"],
                    price=item["price"]
                )
                products.append(product)

    except FileNotFoundError:
        pass


def show_menu():
    print(" __________ E-SHOP __________")
    print("""
    1. LOG IN  
    2. ADD NEW CUSTOMER  
    3. LOG IN AS ADMIN 
    4. EXIT
    """)


class MainMenu(Enum):
    LOG_IN_CUSTOMER = 1
    CREATE_PROFIL = 2
    LOG_IN_ADMIN = 3
    EXIT = 4

    def __str__(self):
        return self.name.replace('_', ' ').title()


def user_choice():
    show_menu()
    while True:

        try:
            choice = int(input("CHOOSE WHAT YOU WANT TO DO: "))
        except ValueError:
            print("Please enter a valid number.")
            continue

        if choice == MainMenu.LOG_IN_CUSTOMER.value:
            # logowanie customera
            customer = login_customer()

            if customer:
                # 2️⃣ Wczytaj produkty do GUI i uruchom okno
                load_products()
                app = EShopGUI(customer)  # przekaż zalogowanego klienta
                app.mainloop()

            continue  # wróć do menu po zamknięciu GUI

        elif choice == MainMenu.CREATE_PROFIL.value:
            # Log in as a new customer

            first_name = input("Write your name: ").capitalize().strip()
            last_name = input("Write your last name: ").capitalize().strip()
            password = input("Write password: ").strip()
            new_customer = Customer(first_name, last_name, password)
            print(f"|The customer has been successfully created in the system: "
                  f"{new_customer.first_name} "
                  f"{new_customer.last_name}, "
                  f"ID: {new_customer.id} |")

            customers.append(new_customer)
            save_customers_to_file(customers)

            if not products:
                print("No products available yet.")
            else:
                print("AVAILABLE PRODUCTS:")
                for i, product in enumerate(products, start=1):
                    product.display_for_customer(i)

            customers.append(new_customer)

        elif choice == MainMenu.LOG_IN_ADMIN.value:
            # LOGIN as admin to the system
            if admin_login():
                admin_panel()

        elif choice == MainMenu.EXIT.value:
            # Quiting programme
            print("PROGRAM FINISHED")
            sys.exit(0)


def show_all_customers():
    print("ALL CUSTOMERS: ")
    if not customers:
        print("No customers yet")
    for customer in customers:
        print(f"{customer.id}: {customer.first_name} {customer.last_name}")
    print()


def login_customer():
    """
    CLI-owe logowanie klienta po jego ID.
    Zwraca obiekt Customer lub None.
    """
    try:
        cid = int(input("Enter your customer ID: "))
    except ValueError:
        print("Invalid ID. Please enter a number.")
        return None

    customer = next((c for c in customers if c.id == cid), None)
    if not customer:
        print("Customer not found.")
        return None

    print(f"Welcome, {customer.first_name}!")
    return customer


def admin_login():
    login = input("Username: ")
    password = input("Password: ")

    if login == "admin" and password == "12345":
        print("Logged in successfully.")
        return True
    else:
        print("Incorrect login or password.")
        return False


class AdminPanel(Enum):
    SHOW_CUSTOMERS = 1
    ADD_PRODUCT = 2
    SHOW_PRODUCTS = 3
    SHOW_SALES = 4
    LOGOUT = 5

    def __str__(self):
        return self.name.replace('_', ' ').title()


def admin_panel():
    admin = Admin("admin")        # INSTANCJA KLASY

    # Here we ask admin what he wants to do as the admin. We use Enum to
    while True:
        print("\n--- ADMIN PANEL ---")
        for option in AdminPanel:
            print(f"{option.value}. {option}")

        try:
            choice = int(input("Choose option: "))
        except ValueError:
            print("Invalid option. Try again.")
            continue

        if choice == AdminPanel.SHOW_CUSTOMERS.value:
            show_all_customers()

        elif choice == AdminPanel.ADD_PRODUCT.value:
            admin.add_product()

        elif choice == AdminPanel.SHOW_PRODUCTS.value:
            admin.show_products()

        elif choice == AdminPanel.SHOW_SALES.value:
            # Here probably we are going to use some analytics libraries (Pandas, matlplotlib)
            pass

        elif choice == AdminPanel.LOGOUT.value:
            print("Logged out from admin panel." + "\n" * 3)
            show_menu()
            break