Shopify cart checkout

shopify: {
  showCart?: boolean;       // default true
  disableWallets?: boolean;   // hide Apple/Google Pay in shopify mode
  optIn?: boolean;
  cart: [
    {
      quantity: 1,
      variant: YOUR_VARIANT_ID,
      product: YOUR_PRODUCT_ID,
      price: 29.99,
      name: 'Product name',
      description?: string,
      imageUrl?: string,
      discountCodeAmount?: 5,
    },
  ],
  shipping?: {
    product: YOUR_SHIPPING_PRODUCT_ID,
    name: 'Standard Shipping',
    price: 4.95,
  },
},

lineTotal = (price - discountCodeAmount) × quantity
subtotal  = sum(lineTotal) excluding shipping product if duplicated in cart
total     = subtotal + shipping.price

{
  productId: YOUR_PRODUCT_ID,
  sessionId: 'YOUR_SESSION_ID',
  environment: 'sandbox',
  amount: 0,
  savePaymentMethod: true,
  shopify: {
    cart: [{ quantity: 1, variant: YOUR_VARIANT_ID, product: YOUR_PRODUCT_ID, price: 29.99, name: 'Item' }],
    shipping: { product: YOUR_SHIPPING_PRODUCT_ID, name: 'Shipping', price: 4.95 },
  },
  customer: { email: 'customer@example.com', country: 'US' },
}

{
  amount: 0,
  usePreviousPaymentMethod: true,
  upsell: {
    upsellId: 'warranty-upsell',
    initialPaymentSession: paysightSessionFromPage1,
    upsellButton: { text: 'Add to order' },
  },
  shopify: {
    cart: [/* upsell line items */],
  },
}