Auto locale

src/routes/+layout.server.ts

@@ -0,0 +1,18 @@
+import type {LayoutServerLoad} from './$types';
+import {defaultLocale, locales} from "$lib/translations";
+
+export const prerender = true;
+
+export const load: LayoutServerLoad = async ({ request }) => {
+  const supportedLocales = locales.get().map((l) => l.toLowerCase());
+
+  let locale = `${`${request.headers.get('accept-language')}`.match(/[a-zA-Z]+?(?=[-_,;])/)}`.toLowerCase();
+
+  if (!supportedLocales.includes(locale)) {
+    locale = defaultLocale;
+  }
+
+  return {
+    i18n: { locale },
+  };
+}