Shopify Love the code Challenge

// Pranav Kural
// Render HTML code for an order summary
function order_summary(order_object) {

// Declaring the variables  x - cost amount, y - tax amount
  var x, y;

// Setting the value of x based on the amount of purchase (not using ternary to keep it clear and easy to update or edit in future)
// Using Switch Statement as it is more appropriate for the purpose of performing task based on the values of an expression.
    switch (order_object.price_level) {
    case "free":
        x= 0;
        break;
    case "discount":
        x =  order_object.price - (order_object.discount_percentage * order_object.price);
        break;
    case "sale":
        x =  order_object.price - order_object.markdown;
        break;
    default:
        x = order_object.price;
    }

// Preparing the result for the sub total purchase amount
    var subtotal_str = (order_object.price_level == "free") ? "Subtotal: This order is free" : "Subtotal: " + "$" + x;

// Setting the Tax amount to 'y'
    y = (order.taxes_applicable == true) ? order_object.tax : 0;

// Preparing the result for the tax amount
    var tax_str = "Tax: $" + y;

// Here there is no need to declare variable 'y' explicitly as no calculations are performed on it, but still used it anticipating
// future needs.

// Preparing the result for the total order cost
    var total_str = "Order total: " + "$" + x + y;

// Preparing the HTML result for the order
  html = "<h1> Order summary </h1>" + "<p>" + "Product:  " + order_object.product_name  + "</p>" + "<p>" + subtotal_str + "</p>" + "<p>" + tax_str + "</p>" + "<p>" + total_str + "</p>";

// Displaying out the result
  document.write(html);
}