implement localization

app/Http/Middleware/SetLocale.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\App;
+use Illuminate\Support\Facades\Cookie;
+use Symfony\Component\HttpFoundation\Response;
+
+class SetLocale
+{
+    /**
+     * Handle an incoming request.
+     *
+     * @param  Closure(Request): (Response)  $next
+     */
+    public function handle(Request $request, Closure $next): Response
+    {
+        $cookieName = (string) config('localization.cookie', 'locale');
+        $supportedLocales = array_keys((array) config('localization.locales', []));
+        $cookieLocale = $request->cookie($cookieName);
+        $configuredLocale = (string) config('app.locale', 'en');
+
+        $locale = $this->validLocale($cookieLocale, $supportedLocales)
+            ?? $this->validLocale($configuredLocale, $supportedLocales)
+            ?? $this->validLocale((string) config('app.fallback_locale', 'en'), $supportedLocales)
+            ?? 'en';
+
+        App::setLocale($locale);
+
+        $response = $next($request);
+
+        if ($request->hasCookie($cookieName) && $this->validLocale($cookieLocale, $supportedLocales) === null) {
+            $response->headers->setCookie(Cookie::forget(
+                $cookieName,
+                (string) config('session.path', '/'),
+                config('session.domain'),
+            ));
+        }
+
+        return $response;
+    }
+
+    /**
+     * @param  array<int, string>  $supportedLocales
+     */
+    private function validLocale(mixed $locale, array $supportedLocales): ?string
+    {
+        if (! is_string($locale)) {
+            return null;
+        }
+
+        return in_array($locale, $supportedLocales, true) ? $locale : null;
+    }
+}