simplePOS.py

items = ["apple", "banana", "milk", "bread"]
prices = [20, 15, 50, 35]
total = 0

while True:
    print("===========Welcome to the Grocery Store!===========")
    print(f"TYPE OF CUSTOMER:\n1: PWD\n2: Senior Citizen\n3: Regular Customer")
    while True:
        type_of_customer = int(input("Enter type of customer (1-3): "))
        if type_of_customer in [1, 2, 3]:
            break
        print("Invalid input. Please enter 1, 2, or 3.")
    
    print(f"\nMaximum items you can buy is {len(items)}.")
    while True:
        num_items = int(input("How many different items do you want to buy? "))
        if 1 <= num_items <= len(items):
            break
        print(f"Please enter a number between 1 and {len(items)}.")

    print("\nAvailable items and their prices:")
    for x in items:
        print(f"{x}: {prices[items.index(x)]}")

    for i in range(num_items):
        while True:
            item = input(f"\nEnter item name #{i+1}: ").lower()
            if item in items:
                break
            print("Item not found. Please enter a valid item name.")

        while True:
            try:
                qty = int(input(f"Enter quantity of {item}: "))
                if qty > 0:
                    break
                print("Quantity must be greater than 0.")
            except ValueError:
                print("Please enter a valid number.")

        index = items.index(item)
        subtotal = prices[index] * qty
        total += subtotal

    print(f"\nTotal before discount: {total}")

    if total >= 200 and type_of_customer in [1, 2]:
        discount = total * 0.10
        total -= discount
        print("Discount applied: ", discount)
    else:
            print("No discount applied")

    methods = {1: "Gcash", 2: "Google Pay", 3: "Paymaya", 4: "Cash"}
    payment_method = int(input(f"\nPAYMENT METHOD:\n1: {methods[1]}\n2: {methods[2]}\n3: {methods[3]}\n4: {methods[4]}\nEnter payment method (1-4): "))
    match payment_method:
        case 1 | 2 | 3:
            print(f"You paid {total} via {methods[payment_method]}")

        case 4:
            while True:
                cash = int(input("Enter cash amount: "))
                if cash >= total:
                    change = cash - total
                    print(f"Your change is: {change}")
                    break
                print("Insufficient cash. Please enter an amount greater than or equal to the total.")

    print("\nThank you for shopping with us!")

    buy_again = int(input("\nDo you want to buy again? (1: Yes, 2: No): "))
    if buy_again != 1:
        print("===========Goodbye and come again soon!===========")
        break