Implement Shopify Provider

framework/shopify/cart/use-add-item.tsx

@@ -0,0 +1,70 @@
+import { useCallback } from 'react'
+import { CommerceError } from '@commerce/utils/errors'
+import useCart from './use-cart'
+import useCartAddItem, {
+  AddItemInput as UseAddItemInput,
+} from '@commerce/cart/use-add-item'
+import type { HookFetcher } from '@commerce/utils/types'
+import type { Cart } from '@commerce/types'
+import checkoutLineItemAddMutation from '../utils/mutations/checkout-line-item-add'
+import getCheckoutId from '@framework/utils/get-checkout-id'
+import { checkoutToCart } from './utils'
+
+const defaultOpts = {
+  query: checkoutLineItemAddMutation,
+}
+
+export type AddItemInput = UseAddItemInput<any>
+
+export const fetcher: HookFetcher<Cart, any> = async (
+  options,
+  { checkoutId, item },
+  fetch
+) => {
+  if (
+    item.quantity &&
+    (!Number.isInteger(item.quantity) || item.quantity! < 1)
+  ) {
+    throw new CommerceError({
+      message: 'The item quantity has to be a valid integer greater than 0',
+    })
+  }
+
+  const data = await fetch<any, any>({
+    ...options,
+    variables: {
+      checkoutId,
+      lineItems: [item],
+    },
+  })
+
+  return checkoutToCart(data?.checkoutLineItemsAdd)
+}
+
+export function extendHook(customFetcher: typeof fetcher) {
+  const useAddItem = () => {
+    const { mutate, data: cart } = useCart()
+    const fn = useCartAddItem(defaultOpts, customFetcher)
+
+    return useCallback(
+      async function addItem(input: AddItemInput) {
+        const data = await fn({
+          item: {
+            variantId: input.variantId,
+            quantity: input.quantity ?? 1,
+          },
+          checkoutId: getCheckoutId(cart?.id),
+        })
+        await mutate(data, false)
+        return data
+      },
+      [fn, mutate]
+    )
+  }
+
+  useAddItem.extend = extendHook
+
+  return useAddItem
+}
+
+export default extendHook(fetcher)