Moved code into src folder. Added build for component library.

src/components/hooks/useLanguageNames.js

@@ -0,0 +1,36 @@
+import { useState, useEffect } from 'react';
+import { useRouter } from 'next/router';
+import { httpGet } from 'next-basics';
+import enUS from 'public/intl/language/en-US.json';
+
+const languageNames = {
+  'en-US': enUS,
+};
+
+export function useLanguageNames(locale) {
+  const [list, setList] = useState(languageNames[locale] || enUS);
+  const { basePath } = useRouter();
+
+  async function loadData(locale) {
+    const { data } = await httpGet(`${basePath}/intl/language/${locale}.json`);
+
+    if (data) {
+      languageNames[locale] = data;
+      setList(languageNames[locale]);
+    } else {
+      setList(enUS);
+    }
+  }
+
+  useEffect(() => {
+    if (!languageNames[locale]) {
+      loadData(locale);
+    } else {
+      setList(languageNames[locale]);
+    }
+  }, [locale]);
+
+  return list;
+}
+
+export default useLanguageNames;