Supermarket Simulation in Python

supermarket.py

# Function to display greetings and show some promotional items and its price 
def display_greetings(name):
    print(f"Welcome to {name} supermarket! Today's promotional items are:")
    print("----------------------------------------------------------")
    print()

# Function to display items
def display_items(msg, items):
    print(f"{msg}")
    print()
    print("No.\tNama\tHarga")
    print("----------------------------")
    for idx, item_dic in enumerate(items):
        price = format_currency(item_dic['harga'])
        print(f"{idx+1}\t{item_dic['item']}\t{price:>12}")
    print()

# Function to get the user input for either promotional or all items
def get_user_input():
    user_input = input("Do you want to see all items or promotional items only? Type 'all' or 'promotional': ")
    while user_input not in ["all", "promotional"]:
        user_input = input("Invalid input. Please type 'all' or 'promotional': ")
    return user_input

# Function to get the user input what they want to purchase
def get_user_purchase(items):
    user_purchase = {}
    while True:
        item_input = input("\nEnter the item number you want to purchase (press 'q' to finish): ")
        if item_input.lower() == "q":
            break
        elif not item_input.isnumeric() or int(item_input) < 1 or int(item_input) > len(items):
            print("Invalid input. Please enter a valid item number or press 'q' to finish.")
            continue
        item_index = int(item_input) - 1
        item_name = items[item_index]['item']
        item_quantity = input(f"How many {item_name} do you want to buy? ")
        while not item_quantity.isnumeric():
            item_quantity = input(f"Invalid input. Please enter a valid quantity for {item_name}: ")
        item_quantity = int(item_quantity)
        user_purchase[item_name] = user_purchase.get(item_name, 0) + item_quantity
    return user_purchase

# Function to calculate the total price of the user's purchase
def calculate_total_price(user_purchase, all_items):
    total_price = 0
    purchase_details = []
    for item, quantity in user_purchase.items():
        item_dic = {}
        item_price = [x['harga'] for x in all_items if x['item'] == item][0]
        item_total_price = item_price * quantity
        total_price += item_total_price
        item_dic['item'] = item
        item_dic['quantity'] = quantity
        item_dic['item_price'] = item_price
        purchase_details.append(item_dic)
    return total_price, purchase_details

# Function to display total price and details
def display_checkout(total_price, purchase_details):
    print("\nHere are the items you want to buy and its total price:")
    print("No.\tNama\tSatuan Harga\tQty\tTotal Harga")
    print("----------------------------------------------------")
    for idx, item_dic in enumerate(purchase_details):
        item_price = format_currency(item_dic['item_price'])
        item_total_price = format_currency(item_dic['item_price']*item_dic['quantity'])
        print(f"{idx+1}\t{item_dic['item']}\t{item_price:>12}\t{item_dic['quantity']}\t{item_total_price:>12}")
    total_price = format_currency(total_price)
    print(f"\nTotal price:\t\t\t\t{total_price:>12}")

# Function to format currency
def format_currency(price, decimal_separator = ".", currency = "Rp."):
    if decimal_separator == '.':
        return "{}{:,}".format(currency, price).replace(',', '.')
    else:
        return "{}{:,}".format(currency, price)
    
# Define the main function
def main():
    # Define list of all items
    all_items = [
        {"item": "susu", "harga": 50000},
        {"item": "daging", "harga": 20000},
        {"item": "lampu", "harga": 15000},
        {"item": "masker", "harga": 25000},
        {"item": "apel", "harga": 30000}
    ]

    # Define list of promotional items
    promotional_items= [
        {"item": "susu", "harga": 50000},
        {"item": "masker", "harga": 25000}
    ]

    supermarket_name = "ABC"

    display_greetings(supermarket_name)
    display_items("Today's promotional items are:", promotional_items)

    user_input = get_user_input()
    if user_input == "promotional":
        display_items("Here are our promotional items:", promotional_items)        
        user_purchase = get_user_purchase(promotional_items)
    else:
        display_items("Here are all the items available in our supermarket:", all_items)
        user_purchase = get_user_purchase(all_items)

    total_price, purchase_details = calculate_total_price(user_purchase, all_items)

    display_checkout(total_price, purchase_details)

# Call the main function
if __name__ == "__main__":
    main()