first publish

src/app/sitemap.ts

@@ -0,0 +1,42 @@
+import type { MetadataRoute } from "next";
+import { LANGS, routesByLang, type Lang, type PageKey } from "@/lib/i18n";
+import { site } from "@/lib/site";
+
+/** Static export: metadata routes are prerendered; mark explicitly (Next static-exports guide). */
+export const dynamic = "force-static";
+
+type ChangeFrequency = NonNullable<MetadataRoute.Sitemap[number]["changeFrequency"]>;
+
+const pages: ReadonlyArray<{ page: PageKey; changeFrequency: ChangeFrequency; priority: number }> = [
+  { page: "home", changeFrequency: "monthly", priority: 1 },
+  { page: "coaching", changeFrequency: "monthly", priority: 0.8 },
+  { page: "trainings", changeFrequency: "monthly", priority: 0.8 },
+  { page: "keynotes", changeFrequency: "monthly", priority: 0.8 },
+  { page: "impressum", changeFrequency: "yearly", priority: 0.2 },
+  { page: "datenschutz", changeFrequency: "yearly", priority: 0.2 },
+];
+
+/* Die englische Fassung ist eine Übersetzung, keine eigenständige Seite: gleiche
+   Änderungsfrequenz, aber niedrigere Priorität, damit Deutsch die Originalfassung bleibt.
+   Jeder Eintrag nennt über `alternates.languages` beide Fassungen – dasselbe hreflang,
+   das die Seiten im <head> tragen. */
+const PRIORITY_FACTOR: Record<Lang, number> = { de: 1, en: 0.9 };
+
+export default function sitemap(): MetadataRoute.Sitemap {
+  // Evaluated at build time (no request time in a static export): "last modified" = last build.
+  const lastModified = new Date();
+  return LANGS.flatMap((lang) =>
+    pages.map(({ page, changeFrequency, priority }) => ({
+      url: `${site.url}${routesByLang[lang][page]}`,
+      lastModified,
+      changeFrequency,
+      priority: Number((priority * PRIORITY_FACTOR[lang]).toFixed(2)),
+      alternates: {
+        languages: {
+          de: `${site.url}${routesByLang.de[page]}`,
+          en: `${site.url}${routesByLang.en[page]}`,
+        },
+      },
+    })),
+  );
+}