fix broken old links (#457)

middleware.ts

@@ -0,0 +1,39 @@
+import { NextResponse } from "next/server"
+import type { NextRequest } from "next/server"
+
+// List of previous supported language
+const LANGUAGE_CODES = ["en", "it", "de", "es", "fr", "ja", "ko"]
+
+export function middleware(request: NextRequest) {
+  const { pathname } = request.nextUrl
+
+  const languageCode = LANGUAGE_CODES.find((code) =>
+    pathname.startsWith(`/${code}/`)
+  )
+
+  if (languageCode) {
+    const newPathname = pathname.replace(`/${languageCode}`, "")
+    const newUrl = new URL(newPathname, request.url)
+
+    request.nextUrl.searchParams.forEach((value, key) => {
+      newUrl.searchParams.set(key, value)
+    })
+
+    return NextResponse.redirect(newUrl)
+  }
+
+  return NextResponse.next()
+}
+
+export const config = {
+  matcher: [
+    // Match all paths that start with any of the language codes
+    "/en/:path*",
+    "/it/:path*",
+    "/de/:path*",
+    "/es/:path*",
+    "/fr/:path*",
+    "/ja/:path*",
+    "/ko/:path*",
+  ],
+}