> For the complete documentation index, see [llms.txt](https://headless.intelligems.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://headless.intelligems.io/latest-1.2.19/usage/update-atc-events/shopify-plus-+-scripts.md).

# Shopify Plus + Scripts

{% hint style="info" %}
Shopify is deprecating Checkout Scripts! Intelligems highly recommends using functions instead.
{% endhint %}

## Add `useIgCart()`

* Use the [`useIgCart()`](/latest-1.2.19/reference/hooks/cart-and-checkout-hooks.md#useigcart) hook if your site uses the Storefront **Cart** API.
* Wrap ATC calls with the `wrapCustomAttributes` function returned by `useIgCart` when you need line item properties (for example, shipping tests).

## Add Intelligems Script to `checkout.liquid`

The Intelligems script may be found under *settings* at [app.intelligems.io](https://app.intelligems.io). Copy this script tag and add it to the header of `checkout.liquid`.

## Add Intelligems Checkout Script to Script Editor

Add the following script to your Script Editor app as a line item discount.

{% code overflow="wrap" %}

```ruby
class Intelligems
  def initialize(discount_property = '_igp', allow_free = false)
    @volume_discount_property = '_igvd'
    @volume_discount_message_property = '_igvd_message'
    @depreciated_property = '_igLineItemDiscount'
    @discount_property = discount_property
    @allow_free = allow_free
  end

  def discount_product(line_item)
    ig_price = Money.new(cents: line_item.properties[@discount_property])

    discount = line_item.line_price - ig_price
    if discount > Money.zero
      discount *= line_item.quantity
      line_item.change_line_price(line_item.line_price - discount, message: 'Discount')
    end

  end

  def depreciated_discount_product(line_item)
    discount = Money.new(cents: line_item.properties[@depreciated_property])
    discount *= line_item.quantity

    if @allow_free or discount < line_item.line_price
      line_item.change_line_price(line_item.line_price - discount, message: 'Intelligems')
    end
  end

  def volume_discount(line_item)
    discount = Money.new(cents: line_item.properties[@volume_discount_property])
    discount *= line_item.quantity

    if discount < line_item.line_price
      message = line_item.properties[@volume_discount_message_property]
      line_item.change_line_price(line_item.line_price - discount, message: message)
    end
  end

  def run(cart)
    cart.line_items.each do |line_item|
      if !line_item.properties[@discount_property].nil? && !line_item.properties[@discount_property].empty?
        discount_product(line_item)
      elsif !line_item.properties[@volume_discount_property].nil? && !line_item.properties[@volume_discount_property].empty?
        volume_discount(line_item)
      elsif !line_item.properties[@depreciated_property].nil? && !line_item.properties[@depreciated_property].empty?
             depreciated_discount_product(line_item)
      end
    end
  end
end

intelligems = Intelligems.new()
intelligems.run(Input.cart)

Output.cart = Input.cart
```

{% endcode %}


---

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