import type { RawProduct } from "./productsServer";

// A bundle's `bundleItems` is only ever resolved once, at checkout, into a
// plain readable string — the order line stores this snapshot
// (`items[].bundleContents`), not a structured sub-list, so a later change
// to the bundle's own composition can never rewrite what a past order
// actually contained. `product.bundleItems[].product` is a relationship
// resolved by fetchProductsBySlug's depth:2 fetch — {id, name} objects
// when populated, a bare id if depth somehow didn't reach it (skipped).
//
// Extracted out of app/api/checkout/route.ts into its own module (not
// just kept as a local function there) so it's importable from a unit
// test — Next.js route.ts files only allow HTTP-method + a few config
// exports, not arbitrary named exports.
export function describeBundleContents(product: RawProduct): string | null {
  if (!product.bundleItems || product.bundleItems.length === 0) return null;
  return product.bundleItems
    .map((line) => (typeof line.product === "object" ? `${line.quantity}× ${line.product.name}` : null))
    .filter((s): s is string => Boolean(s))
    .join(", ");
}