import type { Metadata } from 'next';
import { notFound, permanentRedirect } from 'next/navigation';
import { ArtifactPage, describeArtifact } from '@/components/entity/artifact-page';
import { ApiError, apiD1, safe } from '@/lib/api';
import { routes, SITE_NAME, SITE_URL } from '@/lib/site';
import type { ModelDetail } from '@/lib/types';

type Params = { params: Promise<{ slug: string }> };

async function load(slug: string): Promise<ModelDetail> {
  try {
    return await apiD1.model(slug);
  } catch (e) {
    if (e instanceof ApiError && e.notFound) notFound();
    throw e;
  }
}

export async function generateMetadata({ params }: Params): Promise<Metadata> {
  const { slug } = await params;
  const d = await safe(apiD1.model(slug));
  if (!d || d.entity_type !== 'artifact' || d.slug !== slug) return { title: 'Artifact', robots: { index: false } };
  const kind = d.artifact_kind ?? 'artifact';
  const title = `${d.name} — ${kind.charAt(0).toUpperCase()}${kind.slice(1)} of ${d.canonical?.name ?? 'a model'}`;
  const description = describeArtifact(d);
  const canonical = routes.artifact(d.slug);
  return { title, description, alternates: { canonical }, openGraph: { title: `${title} | ${SITE_NAME}`, description, url: `${SITE_URL}${canonical}`, type: 'article', siteName: SITE_NAME }, twitter: { card: 'summary_large_image', title, description } };
}

export default async function ArtifactRoute({ params }: Params) {
  const { slug } = await params;
  const d = await load(slug);
  // A model slug under /artifacts → its canonical URL; unknown types → 404.
  if (d.entity_type !== 'artifact') permanentRedirect(routes.entity(d));
  if (d.slug !== slug) permanentRedirect(routes.artifact(d.slug));
  return <ArtifactPage d={d} canonical={routes.artifact(d.slug)} />;
}