Add locale runtime configuration

app/Http/Controllers/Settings/LocaleController.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace App\Http\Controllers\Settings;
+
+use App\Http\Controllers\Controller;
+use App\Http\Requests\Settings\LocaleUpdateRequest;
+use Illuminate\Http\RedirectResponse;
+use Illuminate\Support\Facades\Cookie;
+use Inertia\Inertia;
+
+class LocaleController extends Controller
+{
+    public function update(LocaleUpdateRequest $request): RedirectResponse
+    {
+        $locale = (string) $request->validated('locale');
+
+        if ($request->user() && config('localization.user_preference.enabled')) {
+            $request->user()->forceFill([
+                (string) config('localization.user_preference.column', 'locale') => $locale,
+            ])->save();
+        }
+
+        Cookie::queue(Cookie::make(
+            (string) config('localization.cookie.name', 'locale'),
+            $locale,
+            (int) config('localization.cookie.duration_minutes', 525600),
+            null,
+            null,
+            null,
+            false,
+            false,
+            'lax',
+        ));
+
+        Inertia::flash('toast', ['type' => 'success', 'message' => __('Language preference updated.')]);
+
+        return back();
+    }
+}

app/Http/Middleware/HandleInertiaRequests.php

@@ -38,6 +38,13 @@ public function share(Request $request): array
         return [
             ...parent::share($request),
             'name' => config('app.name'),
+            'locale' => [
+                'active' => app()->getLocale(),
+                'supported' => config('localization.supported_locales'),
+                'default' => config('localization.default_locale'),
+                'fallback' => config('localization.fallback_locale'),
+                'usesRoutePrefixes' => config('localization.use_locale_route_prefixes'),
+            ],
             'auth' => [
                 'user' => $request->user(),
             ],

app/Http/Middleware/HandleLocale.php

@@ -0,0 +1,58 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\App;
+use Symfony\Component\HttpFoundation\Response;
+
+class HandleLocale
+{
+    /**
+     * Handle an incoming request.
+     *
+     * @param  Closure(Request): (Response)  $next
+     */
+    public function handle(Request $request, Closure $next): Response
+    {
+        App::setLocale($this->resolveLocale($request));
+
+        return $next($request);
+    }
+
+    protected function resolveLocale(Request $request): string
+    {
+        $supportedLocales = $this->supportedLocales();
+
+        $candidates = [
+            $request->user()?->getAttribute((string) config('localization.user_preference.column', 'locale')),
+            $request->cookies->get((string) config('localization.cookie.name', 'locale')),
+            $request->headers->has('Accept-Language') ? $request->getPreferredLanguage($supportedLocales) : null,
+            config('localization.default_locale'),
+            config('app.locale'),
+        ];
+
+        foreach ($candidates as $candidate) {
+            if (is_string($candidate) && in_array($candidate, $supportedLocales, true)) {
+                return $candidate;
+            }
+        }
+
+        return 'en';
+    }
+
+    /**
+     * @return list<string>
+     */
+    protected function supportedLocales(): array
+    {
+        $locales = config('localization.supported_locales', []);
+
+        if (! is_array($locales)) {
+            return [];
+        }
+
+        return array_keys($locales);
+    }
+}

app/Http/Requests/Settings/LocaleUpdateRequest.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace App\Http\Requests\Settings;
+
+use Illuminate\Contracts\Validation\ValidationRule;
+use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rule;
+
+class LocaleUpdateRequest extends FormRequest
+{
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * Get the validation rules that apply to the request.
+     *
+     * @return array<string, ValidationRule|array<mixed>|string>
+     */
+    public function rules(): array
+    {
+        return [
+            'locale' => ['required', 'string', Rule::in(array_keys(config('localization.supported_locales', [])))],
+        ];
+    }
+}

app/Models/User.php

@@ -4,6 +4,7 @@
 
 // use Illuminate\Contracts\Auth\MustVerifyEmail;
 use Database\Factories\UserFactory;
+use Illuminate\Contracts\Translation\HasLocalePreference;
 use Illuminate\Database\Eloquent\Attributes\Fillable;
 use Illuminate\Database\Eloquent\Attributes\Hidden;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
@@ -19,6 +20,7 @@
  * @property int $id
  * @property string $name
  * @property string $email
+ * @property string $locale
  * @property Carbon|null $email_verified_at
  * @property string $password
  * @property string|null $two_factor_secret
@@ -28,9 +30,9 @@
  * @property Carbon|null $created_at
  * @property Carbon|null $updated_at
  */
-#[Fillable(['name', 'email', 'password'])]
+#[Fillable(['name', 'email', 'locale', 'password'])]
 #[Hidden(['password', 'two_factor_secret', 'two_factor_recovery_codes', 'remember_token'])]
-class User extends Authenticatable implements PasskeyUser
+class User extends Authenticatable implements HasLocalePreference, PasskeyUser
 {
     /** @use HasFactory<UserFactory> */
     use HasFactory, HasRoles, Notifiable, PasskeyAuthenticatable, TwoFactorAuthenticatable;
@@ -48,4 +50,9 @@ protected function casts(): array
             'two_factor_confirmed_at' => 'datetime',
         ];
     }
+
+    public function preferredLocale(): string
+    {
+        return $this->locale;
+    }
 }

bootstrap/app.php

@@ -2,6 +2,7 @@
 
 use App\Http\Middleware\HandleAppearance;
 use App\Http\Middleware\HandleInertiaRequests;
+use App\Http\Middleware\HandleLocale;
 use Illuminate\Foundation\Application;
 use Illuminate\Foundation\Configuration\Exceptions;
 use Illuminate\Foundation\Configuration\Middleware;
@@ -15,10 +16,11 @@
         health: '/up',
     )
     ->withMiddleware(function (Middleware $middleware): void {
-        $middleware->encryptCookies(except: ['appearance', 'sidebar_state']);
+        $middleware->encryptCookies(except: ['appearance', 'locale', 'sidebar_state']);
 
         $middleware->web(append: [
             HandleAppearance::class,
+            HandleLocale::class,
             HandleInertiaRequests::class,
             AddLinkHeadersForPreloadedAssets::class,
         ]);

config/localization.php

@@ -0,0 +1,79 @@
+<?php
+
+return [
+
+    /*
+    |--------------------------------------------------------------------------
+    | Supported Locales
+    |--------------------------------------------------------------------------
+    |
+    | DDS publishes content in English and Dutch. The public route structure
+    | stays unprefixed in phase 1; locale choice is a content concern, not a
+    | URL segment concern.
+    |
+    */
+
+    'supported_locales' => [
+        'en' => [
+            'name' => 'English',
+            'native_name' => 'English',
+        ],
+        'nl' => [
+            'name' => 'Nederlands',
+            'native_name' => 'Nederlands',
+        ],
+    ],
+
+    'default_locale' => env('APP_LOCALE', 'en'),
+
+    'fallback_locale' => env('APP_FALLBACK_LOCALE', 'en'),
+
+    'use_locale_route_prefixes' => false,
+
+    'cookie' => [
+        'name' => 'locale',
+        'duration_minutes' => 60 * 24 * 365,
+    ],
+
+    'user_preference' => [
+        'enabled' => true,
+        'column' => 'locale',
+    ],
+
+    /*
+    |--------------------------------------------------------------------------
+    | Translatable Content Fields
+    |--------------------------------------------------------------------------
+    |
+    | Phase 1 stores translatable content in JSON columns keyed by locale, for
+    | example: {"en": "Title", "nl": "Titel"}. Admin forms should render one
+    | field per supported locale for these attributes and persist the combined
+    | locale map back to the JSON column.
+    |
+    */
+
+    'translatable_content' => [
+        'storage' => 'json_by_locale',
+        'required_locale' => 'en',
+        'fallback_locale' => 'en',
+    ],
+
+    /*
+    |--------------------------------------------------------------------------
+    | Frontend Translation Bundles
+    |--------------------------------------------------------------------------
+    |
+    | When React UI strings become translatable, store JSON bundles using this
+    | shape: resources/js/locales/{domain}/{locale}/{namespace}.json.
+    | Examples: frontend/nl/navigation.json, backend/en/settings.json,
+    | global/nl/validation.json.
+    |
+    */
+
+    'frontend_translations' => [
+        'path_pattern' => 'resources/js/locales/{domain}/{locale}/{namespace}.json',
+        'domains' => ['frontend', 'backend', 'global'],
+        'namespace_separator' => '/',
+    ],
+
+];

database/factories/UserFactory.php

@@ -27,6 +27,7 @@ public function definition(): array
         return [
             'name' => fake()->name(),
             'email' => fake()->unique()->safeEmail(),
+            'locale' => 'en',
             'email_verified_at' => now(),
             'password' => static::$password ??= Hash::make('password'),
             'remember_token' => Str::random(10),

database/migrations/0001_01_01_000000_create_users_table.php

@@ -15,6 +15,7 @@ public function up(): void
             $table->id();
             $table->string('name');
             $table->string('email')->unique();
+            $table->string('locale', 5)->default('en');
             $table->timestamp('email_verified_at')->nullable();
             $table->string('password');
             $table->rememberToken();

docs/backlog/initial-build-backlog.md

@@ -8,7 +8,7 @@ This backlog translates the preparation docs into the first practical implementa
 - React, Inertia, TypeScript, and Tailwind;
 - DDEV with PostgreSQL;
 - custom admin, no Filament in phase 1;
-- Dutch-first bilingual content with `nl` and `en`;
+- English-default bilingual content with `en` and `nl`;
 - no locale-prefixed URLs in phase 1;
 - public dated activities are called `Events`;
 - trainings are `Event` records with `type = training`;
@@ -244,11 +244,34 @@ Tasks:
 
 Acceptance criteria:
 
-- app default locale is `nl`;
+- app default locale is `en`;
 - supported locales are explicit in config;
 - no `/nl` or `/en` route prefix is required;
 - implementation notes describe how translatable content fields should be stored.
 
+### DDS-006A: Runtime Locale And Translation UX
+
+Goal: turn the locale configuration into a runtime language experience, using useful patterns from NIPKaart without introducing locale-prefixed URLs.
+
+Tasks:
+
+- add request locale middleware that chooses the locale from an authenticated user preference, a guest cookie, browser preference, and finally the configured default;
+- keep supported locale validation driven by locale config instead of hardcoded locale lists;
+- share the active locale and supported locales with Inertia;
+- decide whether users need a persisted `locale` preference in phase 1 or whether guest-cookie behavior is enough until account settings mature;
+- add a small language switcher only when there are translated UI strings to switch between;
+- define the frontend translation bundle shape for React, likely JSON namespaces grouped by domain such as `frontend`, `backend`, and `global`;
+- avoid adding locale route prefixes, redirects, or duplicate page URLs.
+
+Acceptance criteria:
+
+- the active locale can be resolved per request without changing the URL shape;
+- unsupported locale values are rejected or ignored consistently;
+- Inertia pages can read the active locale from shared props;
+- the selected approach works for both guests and authenticated users;
+- frontend translation files have a predictable namespace convention;
+- the implementation remains optional for pages that still use plain placeholder copy.
+
 ## Epic 3: Core Public Structure
 
 ### DDS-007: Public Static Shell Pages
@@ -523,17 +546,18 @@ Acceptance criteria:
 6. DDS-004B
 7. DDS-005
 8. DDS-006
-9. DDS-007
-10. DDS-009
-11. DDS-010
-12. DDS-011
-13. DDS-012
-14. DDS-013
-15. DDS-014
-16. DDS-014A
-17. DDS-014B
-18. DDS-014C
-19. DDS-015
-20. DDS-016
+9. DDS-006A
+10. DDS-007
+11. DDS-009
+12. DDS-010
+13. DDS-011
+14. DDS-012
+15. DDS-013
+16. DDS-014
+17. DDS-014A
+18. DDS-014B
+19. DDS-014C
+20. DDS-015
+21. DDS-016
 
 The public website rebuild can begin once DDS-007 and DDS-010 exist, while admin and import work continue behind it.