Use correct locale, fall back to en if we don't have translations

FREEBIE

js/i18n.js

@@ -3,12 +3,16 @@
  */
 ;(function() {
     'use strict';
-    var json = window.config.locale_json;
+
+    // preload.js loads this, pulling it from main.js (where it was loaded from disk)
+    var messages = window.config.localeMessages;
+    var locale = window.config.locale;
+
     window.i18n = function (message, substitutions) {
-      if (!json[message]) {
+      if (!messages[message]) {
         return;
       }
-      var s = json[message].message;
+      var s = messages[message].message;
       if (substitutions instanceof Array) {
         substitutions.forEach(function(sub) {
           s = s.replace(/\$.+?\$/, sub);
@@ -20,6 +24,6 @@
     };
 
     i18n.getLocale = function() {
-      return window.config.locale;
+      return locale;
     };
 })();

main.js

@@ -89,11 +89,39 @@ function createWindow () {
     mainWindow.flashFrame(false);
   });
 
-  // Load locale
-  const locale = 'en'; // FIXME
-  const localeData = JSON.parse(fs.readFileSync(path.join(__dirname, '_locales', locale, 'messages.json'), 'utf-8'))
+  function loadLocale() {
+    // possible locales: https://github.com/electron/electron/blob/master/docs/api/locales.md
+    const locale = app.getLocale();
+
+    if (/^en-/.test(locale)) {
+      return 'en';
+    }
+
+    return locale;
+  }
+
+  function loadLocaleMessages(locale) {
+    const onDiskLocale = locale.replace('-', '_');
+    const targetFile = path.join(__dirname, '_locales', onDiskLocale, 'messages.json');
+
+    return JSON.parse(fs.readFileSync(targetFile, 'utf-8'))
+  }
+
+  // Load locale - if we can't load messages for the current locale, we default to 'en'
+  var locale = loadLocale();
+  var messages;
+  try {
+    messages = loadLocaleMessages(locale);
+  }
+  catch (e) {
+    console.log('Problem loading messages for locale ', locale, e.stack);
+    locale = 'en';
+    messages = loadLocaleMessages(locale);
+  }
+
+  // Ingested in preload.js via a sendSync call
   ipc.on('locale-data', function(event, arg) {
-    event.returnValue = localeData;
+    event.returnValue = messages;
   });
 
   function prepareURL(pathSegments) {

preload.js

@@ -6,7 +6,7 @@
   window.config = require('url').parse(window.location.toString(), true).query;
 
   const ipc = electron.ipcRenderer
-  window.config.locale_json = ipc.sendSync('locale-data');
+  window.config.localeMessages = ipc.sendSync('locale-data');
 
   window.setBadgeCount = function(count) {
     ipc.send('set-badge-count', count);

test/i18n_test.js

@@ -0,0 +1,25 @@
+describe('i18n', function() {
+  describe('i18n', function() {
+    it('returns undefined for unknown string', function() {
+      assert.strictEqual(i18n('random'), undefined);
+    });
+    it('returns message for given string', function() {
+      assert.equal(i18n('reportIssue'), 'Report an issue');
+    });
+    it('returns message with single substitution', function() {
+      const actual = i18n('attemptingReconnection', 5);
+      assert.equal(actual, 'Attempting reconnect in 5 seconds')
+    });
+    it('returns message with multiple substitutions', function() {
+      const actual = i18n('verifyContact', ['<strong>', '</strong>']);
+      assert.equal(actual, 'You may wish to <strong> verify </strong> your safety number with this contact.');
+    });
+  });
+
+  describe('getLocale', function() {
+    it('returns a string with length two or greater', function() {
+      const locale = i18n.getLocale();
+      assert.isAtLeast(locale.trim().length, 2);
+    });
+  });
+});

test/index.html

@@ -574,6 +574,8 @@
   <script type="text/javascript" src="../js/reliable_trigger.js" data-cover></script>
   <script type="text/javascript" src="test.js"></script>
 
+  <script type='text/javascript' src='../js/i18n.js'></script>
+
   <script type='text/javascript' src='../js/registration.js' data-cover></script>
   <script type="text/javascript" src="../js/expire.js" data-cover></script>
   <script type="text/javascript" src="../js/chromium.js" data-cover></script>
@@ -651,6 +653,7 @@
   <script type="text/javascript" src="emoji_util_test.js"></script>
   <script type="text/javascript" src="reliable_trigger_test.js"></script>
   <script type="text/javascript" src="backup_test.js"></script>
+  <script type="text/javascript" src="i18n_test.js"></script>
 
   <script type="text/javascript" src="fixtures.js"></script>
   <script type="text/javascript" src="fixtures_test.js"></script>