feat: improve instantiation of intl

apps/scandic-web/i18n/Provider.tsx

@@ -2,11 +2,21 @@
 
 import { IntlProvider } from "react-intl"
 
-import type { ServerIntlProviderProps } from "@/types/i18n"
+import type { ClientIntlProviderProps } from "@/types/i18n"
 
-export default function ServerIntlProvider({
+export default function ClientIntlProvider({
   children,
-  intl,
-}: ServerIntlProviderProps) {
-  return <IntlProvider {...intl}>{children}</IntlProvider>
+  locale,
+  defaultLocale,
+  messages,
+}: ClientIntlProviderProps) {
+  return (
+    <IntlProvider
+      locale={locale}
+      defaultLocale={defaultLocale}
+      messages={messages}
+    >
+      {children}
+    </IntlProvider>
+  )
 }

apps/scandic-web/i18n/index.ts

@@ -1,32 +1,36 @@
 import "server-only"
 
 import { createIntl, createIntlCache } from "@formatjs/intl"
-import { headers } from "next/headers"
 
 import { Lang } from "@/constants/languages"
 
+import { getLang } from "@/i18n/serverContext"
+
+import type { IntlShape } from "react-intl"
+
 const cache = createIntlCache()
 
-export async function initIntl(lang: Lang) {
-  return createIntl<React.ReactNode>(
-    {
-      defaultLocale: Lang.en,
-      locale: lang,
-      messages: (await import(`./dictionaries/${lang}.json`)).default,
-    },
-    cache
-  )
+const instances: Partial<Record<Lang, IntlShape>> = {}
+
+export async function getMessages(lang: Lang): Promise<Record<string, string>> {
+  return (await import(`./dictionaries/${lang}.json`)).default
 }
 
-export async function getIntl(forceLang?: Lang) {
-  const h = headers()
-  let lang = h.get("x-lang") as Lang
-  if (!lang) {
-    lang = Lang.en
+export async function getIntl() {
+  const lang = getLang()
+
+  if (!instances[lang]) {
+    const messages = await getMessages(lang)
+    instances[lang] = createIntl<React.ReactNode>(
+      {
+        defaultLocale: Lang.en,
+        locale: lang,
+        messages,
+      },
+      cache
+    )
   }
 
-  if (forceLang) {
-    return await initIntl(forceLang)
-  }
-  return await initIntl(lang)
+  // Exclamation mark can be removed once we update TS to 5.8.2+
+  return instances[lang]!
 }