i18n: initial separation of locales and languages

Bug: #123

client/src/javascript/app.tsx

@@ -75,7 +75,7 @@ const FloodApp: FC = observer(() => {
 
   return (
     <Suspense fallback={<LoadingOverlay />}>
-      <AsyncIntlProvider locale={SettingStore.floodSettings.language}>
+      <AsyncIntlProvider language={SettingStore.floodSettings.language}>
         <Router history={history}>
           <AppWrapper className={ConfigStore.preferDark ? 'dark' : undefined}>
             <Switch>

client/src/javascript/i18n/languages.tsx

@@ -8,6 +8,7 @@ import EN from './strings.compiled.json';
 import Languages from '../constants/Languages';
 
 import type {Language} from '../constants/Languages';
+import type {LocaleConfig} from '../util/detectLocale';
 
 const messagesCache: Partial<Record<Exclude<Language, 'auto'>, Record<string, MessageFormatElement[]>>> = {en: EN};
 
@@ -45,28 +46,31 @@ function getMessages(locale: Exclude<Language, 'auto'>) {
 }
 
 interface AsyncIntlProviderProps {
-  locale?: Language;
+  language?: Language;
   children: React.ReactNode;
 }
 
-const AsyncIntlProvider: React.FC<AsyncIntlProviderProps> = ({locale, children}: AsyncIntlProviderProps) => {
-  let validatedLocale: Exclude<Language, 'auto'>;
-  if (locale == null || locale === 'auto' || !Object.prototype.hasOwnProperty.call(Languages, locale)) {
+const AsyncIntlProvider: React.FC<AsyncIntlProviderProps> = ({language, children}: AsyncIntlProviderProps) => {
+  let validatedLocale: LocaleConfig;
+  if (language == null || language === 'auto' || !Object.prototype.hasOwnProperty.call(Languages, language)) {
     validatedLocale = detectLocale();
   } else {
-    validatedLocale = locale;
+    validatedLocale = {
+      locale: language,
+      language,
+    };
   }
 
-  const messages = getMessages(validatedLocale);
+  const messages = getMessages(validatedLocale.language);
   return (
-    <IntlProvider locale={validatedLocale === 'translate' ? 'en' : validatedLocale} messages={messages}>
+    <IntlProvider locale={validatedLocale.language === 'translate' ? 'en' : validatedLocale.locale} messages={messages}>
       {children}
     </IntlProvider>
   );
 };
 
 AsyncIntlProvider.defaultProps = {
-  locale: 'en',
+  language: 'en',
 };
 
 export default AsyncIntlProvider;

client/src/javascript/util/detectLocale.ts

@@ -3,43 +3,54 @@ import Languages from '../constants/Languages';
 
 import type {Language} from '../constants/Languages';
 
-let detectedLocale: Exclude<Language, 'auto'> = 'en';
+export interface LocaleConfig {
+  locale: string;
+  language: Exclude<Language, 'auto'>;
+}
+
+const detectedLocales: LocaleConfig = {
+  locale: 'en',
+  language: 'en',
+};
+
 let localeDetected = false;
 
-function detectLocale(): Exclude<Language, 'auto'> {
+const detectLocale = (): LocaleConfig => {
   if (localeDetected) {
-    return detectedLocale;
+    return detectedLocales;
   }
+
   // Reverse loop to respect language priority of user
   getUserLocales()
     .reverse()
     .forEach((userLocale): void => {
-      let locale = userLocale;
-      switch (locale) {
+      detectedLocales.locale = userLocale;
+      switch (detectedLocales.locale) {
         // Special handlings for languages with variants
         case 'zh':
         case 'zh-CN':
         case 'zh-SG':
         case 'zh-MY':
-          locale = 'zh-Hans';
+          detectedLocales.locale = 'zh-Hans';
           break;
         case 'zh-TW':
         case 'zh-HK':
         case 'zh-MO':
-          locale = 'zh-Hant';
+          detectedLocales.locale = 'zh-Hant';
           break;
         default:
           break;
       }
-      if (Object.prototype.hasOwnProperty.call(Languages, locale)) {
-        detectedLocale = locale as Exclude<Language, 'auto'>;
-      } else if (Object.prototype.hasOwnProperty.call(Languages, locale.substr(0, 2))) {
+      if (Object.prototype.hasOwnProperty.call(Languages, detectedLocales.locale)) {
+        detectedLocales.language = detectedLocales.locale as Exclude<Language, 'auto'>;
+      } else if (Object.prototype.hasOwnProperty.call(Languages, detectedLocales.locale.substr(0, 2))) {
         // In rare cases, user provides a locale (eg. en-US) without fallback (eg. en)
-        detectedLocale = locale.substr(0, 2) as Exclude<Language, 'auto'>;
+        detectedLocales.language = detectedLocales.locale.substr(0, 2) as Exclude<Language, 'auto'>;
       }
     });
+
   localeDetected = true;
-  return detectedLocale;
-}
+  return detectedLocales;
+};
 
 export default detectLocale;