import type { Product, ShippingSummaryEntry } from 'brainerce';
import { buildProductJsonLd, buildBreadcrumbJsonLd, buildProductFaqJsonLd } from 'brainerce';
import { getNonce } from '@/core/lib/nonce';
import { getCanonicalSiteUrl } from '@/core/lib/site-url';
import { resolveCurrency } from '@/core/lib/resolve-currency';

interface ProductJsonLdProps {
  product: Product;
  url: string;
  currency?: string;
  /** From `storeInfo.shipping` — real flat-rate/free zones only. Omitted entirely when unset, never fabricated. */
  shipping?: ShippingSummaryEntry[];
}

/**
 * Product + BreadcrumbList structured data for a product detail page (PDP).
 *
 * Uses the SDK's `buildProductJsonLd` — NEVER hand-roll the schema object
 * here. The builder owns the availability mapping (InStock / BackOrder /
 * OutOfStock from the backend's pre-computed inventory flags), the
 * Offer/AggregateOffer split, identifier emission (gtin/mpn/sku), shipping
 * details, and the aggregateRating gating; a local copy WILL drift from it.
 * The <script> is rendered locally only to attach the CSP nonce (the SDK's
 * jsonLdScriptProps can't).
 */
export async function ProductJsonLd({ product, url, currency, shipping }: ProductJsonLdProps) {
  // Defer to the shared server helper so the env-var + USD fallback chain
  // lives in exactly one place across all server-side currency reads.
  const resolvedCurrency = resolveCurrency(null, currency);
  const nonce = await getNonce();
  const baseUrl = await getCanonicalSiteUrl();

  const productJsonLd = buildProductJsonLd(product, {
    siteUrl: baseUrl,
    path: url,
    currency: resolvedCurrency,
    shipping,
  });

  const breadcrumbJsonLd = buildBreadcrumbJsonLd([
    { name: 'Home', url: baseUrl || '/' },
    { name: 'Products', url: `${baseUrl}/products` },
    { name: product.name, url },
  ]);

  // FAQPage from the product's Q&A — null (no script) when the product has
  // none. The visible FAQ section on the PDP renders the SAME pairs; this is
  // corroboration for engines, never a substitute for visible text.
  const faqJsonLd = buildProductFaqJsonLd(product);

  return (
    <>
      <script
        type="application/ld+json"
        nonce={nonce}
        suppressHydrationWarning
        dangerouslySetInnerHTML={{ __html: serializeJsonLd(productJsonLd) }}
      />
      <script
        type="application/ld+json"
        nonce={nonce}
        suppressHydrationWarning
        dangerouslySetInnerHTML={{ __html: serializeJsonLd(breadcrumbJsonLd) }}
      />
      {faqJsonLd ? (
        <script
          type="application/ld+json"
          nonce={nonce}
          suppressHydrationWarning
          dangerouslySetInnerHTML={{ __html: serializeJsonLd(faqJsonLd) }}
        />
      ) : null}
    </>
  );
}

// Serialize a JSON-LD object for embedding in a <script> tag. Escapes
// `<`, `>`, and `&` to \uXXXX so seller-controlled product fields cannot
// break out of the script element with `</script>` or inject HTML.
function serializeJsonLd(value: unknown): string {
  return JSON.stringify(value)
    .replace(/</g, '\\u003c')
    .replace(/>/g, '\\u003e')
    .replace(/&/g, '\\u0026');
}