init localize

middleware.ts

@@ -0,0 +1,42 @@
+import { NextResponse } from "next/server";
+import type { NextRequest } from "next/server";
+
+const SUPPORTED_LOCALES = ["en", "de"] as const;
+
+function getLocale(request: NextRequest): string {
+  const acceptLang = request.headers.get("accept-language") ?? "";
+  const preferred = acceptLang.split(",")[0]?.trim().slice(0, 2);
+  if (preferred && SUPPORTED_LOCALES.includes(preferred as any)) return preferred;
+  return "en";
+}
+
+export function middleware(request: NextRequest) {
+  const { pathname } = request.nextUrl;
+
+  // API routes and static files pass through
+  if (
+    pathname.startsWith("/api/") ||
+    pathname.includes(".") ||
+    pathname.startsWith("/_next")
+  ) {
+    return NextResponse.next();
+  }
+
+  // Check if pathname already has a supported locale
+  const hasLocale = SUPPORTED_LOCALES.some(
+    (l) => pathname === `/${l}` || pathname.startsWith(`/${l}/`),
+  );
+
+  if (!hasLocale) {
+    const locale = getLocale(request);
+    const url = request.nextUrl.clone();
+    url.pathname = `/${locale}${pathname === "/" ? "" : pathname}`;
+    return NextResponse.redirect(url);
+  }
+
+  return NextResponse.next();
+}
+
+export const config = {
+  matcher: ["/((?!_next|api|favicon.ico).*)"],
+};