import type { MetadataRoute } from "next";
import { getAllEvents, getOffers, getPosts } from "@/lib/payload/content";
import { getSiteUrl, isSiteIndexable } from "@/lib/seo/config";

// Reads live CMS content on every request — must not be statically
// prerendered at build time (no DB is available during `next build`; see
// AGENTS.md / the same convention used by every other CMS-backed route).
export const dynamic = "force-dynamic";

// Static, always-public routes that aren't backed by a dynamic [slug]
// collection. Deliberately excludes: /login, /registrieren, /konto*,
// /admin*, /calendar/*, /auth/*, /termine/*/beitreten, /termine/*/call,
// /api/* — none of those are public content (see app/robots.ts, which
// mirrors this same exclusion list).
const staticRoutes: { path: string; changeFrequency: MetadataRoute.Sitemap[number]["changeFrequency"]; priority: number }[] = [
  { path: "", changeFrequency: "weekly", priority: 1 },
  { path: "/ueber-mich", changeFrequency: "monthly", priority: 0.7 },
  { path: "/angebote", changeFrequency: "monthly", priority: 0.9 },
  { path: "/angebote/singkreise", changeFrequency: "monthly", priority: 0.6 },
  { path: "/aktuelles", changeFrequency: "weekly", priority: 0.7 },
  { path: "/termine", changeFrequency: "weekly", priority: 0.7 },
  { path: "/termin-buchen", changeFrequency: "monthly", priority: 0.8 },
  { path: "/kontakt", changeFrequency: "yearly", priority: 0.5 },
  { path: "/impressionen", changeFrequency: "monthly", priority: 0.3 },
  { path: "/impressum", changeFrequency: "yearly", priority: 0.1 },
  { path: "/datenschutz", changeFrequency: "yearly", priority: 0.1 },
];

export default async function sitemap(): Promise<MetadataRoute.Sitemap> {
  if (!(await isSiteIndexable())) return [];

  const siteUrl = await getSiteUrl();
  const now = new Date();

  const entries: MetadataRoute.Sitemap = staticRoutes.map((route) => ({
    url: `${siteUrl}${route.path}`,
    lastModified: now,
    changeFrequency: route.changeFrequency,
    priority: route.priority,
  }));

  // getOffers/getAllEvents/getPosts already only return published,
  // publicly-readable documents (overrideAccess: false — see
  // lib/payload/content.ts's header comment).
  const [offers, events, posts] = await Promise.all([getOffers(), getAllEvents(), getPosts()]);

  for (const offer of offers) {
    if (!offer.slug || offer.visibility === "private") continue;
    entries.push({
      url: `${siteUrl}/angebote/${offer.slug}`,
      lastModified: new Date(offer.updatedAt),
      changeFrequency: "monthly",
      priority: 0.8,
    });
  }

  for (const event of events) {
    // Private single-session bookings must never appear in the sitemap.
    if (!event.slug || event.isPrivateBooking) continue;
    entries.push({
      url: `${siteUrl}/termine/${event.slug}`,
      lastModified: new Date(event.updatedAt),
      changeFrequency: "weekly",
      priority: 0.6,
    });
  }

  for (const post of posts) {
    if (!post.slug) continue;
    entries.push({
      url: `${siteUrl}/aktuelles/${post.slug}`,
      lastModified: new Date(post.updatedAt),
      changeFrequency: "monthly",
      priority: 0.6,
    });
  }

  return entries;
}