# Functions go here
def make_statement(statement, decoration):
    """Emphasises headings by adding decoration at the start and end"""
    return f"{decoration * 3} {statement} {decoration * 3}"

def string_check(question, valid_answers=('yes', 'no'), num_letters=1):
    """Checks that users enter the full word or the 'n' letter/s of a word from a list of valid responses"""
    while True:
        response = input(question).lower()

        for item in valid_answers:
            # check if the response is the entire word
            if response == item:
                return item

            # check if it's the "n" letters
            elif response == item[:num_letters]:
                return item

        print(f"Please choose an option from {valid_answers}")

def instructions():
    print(make_statement("Instructions", "ℹ️"))

    print('''
Instructions blah blah blah
    ''')

def not_blank(question):
    """Checks that a user response is not blank"""

    while True:
        response = input(question)

        if response != "":
            return response

        print("Sorry this can't be blank. Please try again. \n")


def int_check(question, low, high):
    """Checks users enter an integer"""

    error = f"❗ Invalid input. Please enter a valid number. ❗\n"

    while True:

        to_check = input(question)

        if to_check == "quit":
            return "quit"

        try:
            # change the response to an integer that it's more than zero
            response = int(input(question))

            return response

        except ValueError:
            print(error)

def currency(x):
    """Formats numbers as currency ($#.##)"""
    return "${:.2f}".format(x)

# Main routine goes here






# Program main heading
print(make_statement("Car Budget Buyer", "🚗"))
print()

# Asks users name
name = not_blank("Hello! What's your name? ")

# Ask user if they want to see the instructions
# Display them if necessary
print()
want_instructions = string_check(f"Hi {name}, Would you like a tutorial/explanation on how the program works? ")

if want_instructions == "yes":
    instructions()

print()

# Ask for budget
print(f"\nAlright {name}, Let's find a car you can afford!")
while True:
    budget = int_check("Enter your budget (minimum $5000): $")
    if budget < 5000:
        print()
        print("❗ please enter a whole number that's $5000 or more ❗\n")
    else:
        print()
        print(f"Your budget is set to ${budget}.\n")
        break

# Shopping cart
cart = []

#Display items
cars = [
    {"item": "Basic Car", "price": 5000, "quantity": 10},
    {"item": "Standard Car", "price": 10000, "quantity": 5},
    {"item": "Luxury Car", "price": 25000, "quantity": 2},
    {"item": "Sports Car", "price": 50000, "quantity": 1},
]

# Shows list
while True:
    affordable_cars = [car for car in cars if car["price"] <= budget and car["quantity"] > 0]
    if not(affordable_cars):
        print("You can't afford any more cars or stock is out. Time to checkout.")
        break

    print("Cars you can afford:")
    for i, car in enumerate(affordable_cars, start=1):
        print(f"{i}. {car['item']} - ${car['price']} (In stock: {car['quantity']})")
    print()

    choice = int_check("Which car would you like to purchase?, or type '0' to quit: ").lower()
    if choice == "0":
        break


    # Adds car selected to cart

















# Checkout
if not cart:
    print("Thank you for using Car Budget Buyer!")
    exit()

print(make_statement("🛒 Checkout Summary", "🛒"))






# ---- Receipt Generation ----