Vending Machine

A standard vending machine CLI application. The app displays a menu of items from which the user picks one associated code (key).

Once an item is selected (and validated), payment is requested in the form of cash or card.

Once payment is received and added to the vending machine's balance, the item is dispensed, it's inventory updated, and any change is returned.

Finally, we ask the user if they'd like to continue with another purchase, if so, we re-run the updated app again with our cached values, if not, we close our app.

Outline:

Objects:

    Item:
        __init__:
            instance attributes:
                name : str
                price : float
                stock : int (default=10)


     VendingMachine:
        __init__:
            instance attributes:
                inventory : dict
                transaction_amount : float
                selection : Item
                balance : float
                active : bool

        display():
            displays all inventory and Item class details (code, name, price) for available items

        purchase_item():
            take input of code (validated)
            check if item in stock
            request payment method

        payment():
            take input of payment method
            call method of payment type entered

        cash():
            validate cash input
            register amount entered
                if < selection price
                    recall method for additional money input
                if >= selection price
                    item dispensed
                    return change if any
                    decrement item stock
                    add price to machine balance

        credit():
            credit card is 'processed'
            item dispensed
            decrement item stock
            add price to machine balance

        is_active():
            called after a purchase to continue or end operations
            sets active attribute bool flag
                if TRUE - loop back to purchase method
                if FALSE - end operations

        * private static method
        _validate_numeric (category: str, msg: str):
            takes in category(code or payment) and input message
            accepts input and casts to category type
                loop through if unable to convert input