Cart

cart.py

import json

#  Within this challenge, you need to design a "shopping cart". You already have:

#  1. The definition of a "cart item"; a class that describes an entry within the "cart".
#  2. The definition of a "stock snapshot"; a class that describes an amount of stock available for a given item.
 
#  Your task is to implement the "Cart".

#  In the first part of this exercise, you should implement the "purchaseable_items" method. This method receives
#  a set of products, and a set of "stock snapshots". You need to determine which if the cart items supplied are
#  actually purchasable.

#  In this initial pass, you should only need to modify purchasable_items

class CartItem:
    """A representation of a given product that the users would like to add to their cart.
    """
    def __init__(self, item_id, product_group, product_id, product_price):
        self.item_id = item_id
        self.product_group = product_group
        self.product_id = product_id
        self.product_price = product_price

class StockSnapshot:
    """A representation of the quantity of items available in a given "warehouse" (or stock pool)
    """
    def __init__(self, product_id, quantity):
        self.product_id = product_id
        self.quantity = quantity

class Cart:
    """TODO: Implement this

    Cart represents the items that the user intends to purchase.
    """
    def purchasable_items(self, cart_items, stock_snapshots):
        # check for product in cart_items that are  in StockSnapshot
        self.cart_items = cart_items
        purchasable_items = []
        self.stock_snapshots = stock_snapshots

        for item in cart_items:           
            
            for stock in stock_snapshots:
                #print(item.product_id,stock.product_id)
                if item.product_id == stock.product_id:                    
                    purchasable_items.append(item,stock)
                    print(purchasable_items)
                
        return purchasable_items

# Example
if __name__ == '__main__':
        item_a = CartItem("1", "t-shirt", "t-shirt-m", 5.0)
        item_b = CartItem("2", "t-shirt", "t-shirt-m", 5.0)


        snapshot_a = StockSnapshot("1", 15.0)
        snapshot_b = StockSnapshot("2", 0.0)

        cart = Cart()
        purchasable = cart.purchasable_items([item_a, item_b], [snapshot_a, snapshot_b])

        for p in purchasable:
            print(json.dumps(p.__dict__))