Stage M1

apps/admin/src/i18n/actions.ts

@@ -0,0 +1,32 @@
+'use server';
+
+import { revalidatePath } from 'next/cache';
+import { cookies } from 'next/headers';
+
+import { isLocale, type Locale } from '@sport/types';
+
+import { LOCALE_COOKIE } from './request';
+
+/**
+ * Persists the operator's language choice.
+ *
+ * A Server Action rather than a client-side cookie write, so the very next
+ * render already has the new locale — no flash of the previous language, and no
+ * need to duplicate the cookie name in client code.
+ */
+export async function setLocale(locale: Locale): Promise<void> {
+  if (!isLocale(locale)) return;
+
+  const store = await cookies();
+  store.set(LOCALE_COOKIE, locale, {
+    path: '/',
+    maxAge: 60 * 60 * 24 * 365,
+    sameSite: 'lax',
+    // Not httpOnly: this is a display preference, not a credential, and reading
+    // it client-side is occasionally useful.
+    httpOnly: false,
+  });
+
+  // Every admin screen renders translated text, so the whole tree is stale.
+  revalidatePath('/', 'layout');
+}