Requirements

Requirements

Requirement #1: Add OOP Logic

For this exercise you will be creating a Checkout class

It will have the following properties…

  • items: which should be start out as an empty array

  • subtotal: which should start out as 0

It should have the following methods…

  • addItem(item):

    • accepts an item object as a parameter

    • this method adds a new item to the items property (remember this property should be an array)

    • Each item object should be structured as follows:

    {
      id: 1,
      name: 'something cool',
      price: '9.99',
      quantity: 1,
    }

  • calculateSubtotal():

    • calculates and updates the subtotal property based on the items in the order

  • calculateTax():

    • calculates the sales tax based on the tax rate (8.875%) and the current subtotal

  • calculateTotal():

    • calculates the total amount based on the sales tax and the current subtotal

  • incrementQuantity(itemId):

    • accepts an itemId as the parameter

    • this method should take the itemId and use it to find the item in the items (array) property that matches itemId; after which, it will increment the quantity of the matched item by 1

  • decrementQuantity(itemId):

    • which accepts an itemId as the parameter

    • this method should take the itemId and use it to find the item in the items (array) property that matches itemId; after which, it will decrement the quantity of the matched item by 1

  • removeItem(itemId):

    • accepts an itemId as the parameter

    • this method should take the ‘itemId’ and use it to find the item in the items (array) property that matches itemId; after which, it will remove the matched item from the items property

Tip: Use console.log() as a means of testing to ensure all of your OOP logic works before moving on to Requirement #2

Requirement #2: Wire up the UI logic

Combine the OOP logic from Requirement #1 with the existing UI code to “wire up” the application (i.e. make the application fully functional).

This will require reviewing the existing UI code and understanding how it works.

Any changes made the UI should also be reflected in your OOP logic. For example, when a users adds a new item from the UI, that new item should be also be “added” to the instance of the Checkout class via the addItem(item) method

Tip: use the generateRandomId() function to generate a random id when adding a new item from the UI