Add language selector on site (fixes #64) (#76)

* Add language selector on site (fixes #64)

* review fixes

src/assets/css/main.css

@@ -60,3 +60,8 @@ img {
   border-color: #FFD700 !important;
   color: #FFD700;
 }
+
+.language-selector {
+  margin-top: 7px;
+  background-color: #333;
+}

src/client/index.tsx

@@ -1,10 +1,17 @@
 import { hydrate } from "inferno-hydrate";
 import { BrowserRouter } from "inferno-router";
 import { App } from "../shared/components/app";
-import { i18n } from "../shared/i18next";
+import { getLanguageFromCookie, i18n } from "../shared/i18next";
 
 // Setting the language for js browsers
-i18n.changeLanguage(navigator.language);
+// If query param is set, server updates cookie automatically,
+// so no need to check the query here
+const languageCookie = getLanguageFromCookie(document.cookie);
+if (languageCookie != null) {
+  i18n.changeLanguage(languageCookie);
+} else {
+  i18n.changeLanguage(navigator.language);
+}
 
 const wrapper = (
   <BrowserRouter>

src/server/index.tsx

@@ -7,7 +7,7 @@ import { App } from "../shared/components/app";
 // import { routes } from "../shared/routes";
 import process from "process";
 import { Helmet } from "inferno-helmet";
-import { i18n } from "../shared/i18next";
+import { getLanguageFromCookie, i18n } from "../shared/i18next";
 
 const server = express();
 const port = 1234;
@@ -23,10 +23,21 @@ server.get("/*", async (req, res) => {
   const context = {} as any;
 
   // Setting the language for non-js browsers
-  let lang = req.headers["accept-language"]
-    ? req.headers["accept-language"].split(",")[0]
-    : "en";
-  i18n.changeLanguage(lang);
+  const cookieLang = getLanguageFromCookie(req.headers.cookie);
+  var language: string;
+  if (req.query["lang"] != null) {
+    language = req.query["lang"].toString();
+    res.cookie("lang", language, {
+      expires: new Date(Date.now() + 60 * 60 * 24 * 7),
+    });
+  } else if (cookieLang != null) {
+    language = cookieLang;
+  } else {
+    language = req.headers["accept-language"]
+      ? req.headers["accept-language"].split(",")[0]
+      : "en";
+  }
+  i18n.changeLanguage(language);
 
   const wrapper = (
     <StaticRouter location={req.url} context={context}>

src/shared/components/navbar.tsx

@@ -1,13 +1,22 @@
-import { Component } from "inferno";
+import { Component, ChangeEvent, linkEvent } from "inferno";
 import { Link } from "inferno-router";
 import { LinkLine } from "./link-line";
 import { Icon } from "./icon";
+import { getLanguageName, i18n } from "../i18next";
 
 export class Navbar extends Component<any, any> {
   constructor(props: any, context: any) {
     super(props, context);
   }
 
+  handleLanguageChange(_: any, event: ChangeEvent<HTMLSelectElement>) {
+    location.href = `/?lang=${event.target.value}`;
+  }
+
+  languageList() {
+    return Object.keys(i18n.services.resourceStore.data).sort();
+  }
+
   render() {
     return (
       <>
@@ -23,6 +32,22 @@ export class Navbar extends Component<any, any> {
             <LinkLine />
           </div>
           <div class="nav-right">
+            <div>
+              <select
+                onChange={linkEvent(this, this.handleLanguageChange)}
+                class="text-light bd-dark language-selector"
+              >
+                {this.languageList().map((language, i) => (
+                  <option
+                    key={i}
+                    value={language}
+                    selected={i18n.language.startsWith(language)}
+                  >
+                    {getLanguageName(language)}
+                  </option>
+                ))}
+              </select>
+            </div>
             <a href="https://github.com/LemmyNet">
               <Icon icon="github" />
             </a>

src/shared/i18next.ts

@@ -60,6 +60,36 @@ const resources = {
   pt,
 };
 
+const languageNames = {
+  en: "English",
+  ru: "Русский",
+  zh: "中文",
+  es: "Español",
+  eu: "Euskara",
+  bg: "Български",
+  nl: "Nederlands",
+  fi: "Suomi",
+  fr: "Français",
+  el: "Ελληνικά",
+  ko: "한국어",
+  pl: "Polski",
+  ar: "العربية",
+  eo: "Esperanto",
+  de: "Deutsch",
+  gl: "Galego",
+  it: "Italiano",
+  ja: "日本語",
+  km: "ភាសាខ្មែរ",
+  nb_NO: "Norsk (Bokmål)",
+  zh_Hant: "文言",
+  fa: "فارسی",
+  id: "Bahasa Indonesia",
+  mnc: "ᠮᠠᠨᠵᡠ ᡤᡳᠰᡠᠨ",
+  sv: "Svenska",
+  vi: "Tiếng Việt",
+  pt: "Português",
+};
+
 function format(value: any, format: any): any {
   return format === "uppercase" ? value.toUpperCase() : value;
 }
@@ -68,7 +98,6 @@ i18next.init({
   debug: false,
   // load: 'languageOnly',
   // initImmediate: false,
-  lng: "en", // This is changed later
   fallbackLng: "en",
   resources,
   interpolation: { format },
@@ -77,3 +106,23 @@ i18next.init({
 export const i18n = i18next as i18nTyped;
 
 export { resources };
+
+export function getLanguageName(key: string): string {
+  return languageNames[key];
+}
+
+// https://gist.github.com/hunan-rostomyan/28e8702c1cecff41f7fe64345b76f2ca
+export function getLanguageFromCookie(cookies?: string): string | null {
+  if (cookies == null) {
+    return null;
+  }
+
+  const key = "lang=";
+  return (
+    cookies
+      .split(";")
+      .map(c => c.trim())
+      .filter(cookie => cookie.substring(0, key.length) === key)
+      .map(cookie => cookie.substring(key.length))[0] || null
+  );
+}