Improve braille related message descriptions and clean up message handling in Chromevox.

chrome/browser/resources/chromeos/chromevox/common/msgs.js

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+
+/**
+ * @fileoverview Defines methods related to retrieving translated messages.
+ */
+
+goog.provide('Msgs');
+
+/**
+ * @constructor
+ */
+Msgs = function() {};
+
+/**
+ * The namespace for all Chromevox messages.
+ * @type {string}
+ * @const
+ * @private
+ */
+Msgs.NAMESPACE_ = 'chromevox_';
+
+/**
+ * Dictionary of locale names.
+ * @type {Object<string>}
+ * @private
+ */
+Msgs.localeNameDict_ = null;
+
+/**
+ * Return the current locale.
+ * @return {string} The locale.
+ */
+Msgs.getLocale = function() {
+  return chrome.i18n.getMessage('locale');
+};
+
+/**
+ * Returns the message with the given message id from the ChromeVox namespace.
+ *
+ * If we can't find a message, throw an exception.  This allows us to catch
+ * typos early.
+ *
+ * @param {string} messageId The id.
+ * @param {Array<string>=} opt_subs Substitution strings.
+ * @return {string} The localized message.
+ */
+Msgs.getMsg = function(messageId, opt_subs) {
+  var message = Msgs.Untranslated[messageId.toUpperCase()];
+  if (message !== undefined)
+    return message;
+  message = chrome.i18n.getMessage(
+      Msgs.NAMESPACE_ + messageId, opt_subs);
+  if (message == undefined || message == '') {
+    throw new Error('Invalid ChromeVox message id: ' + messageId);
+  }
+  return message;
+};
+
+/**
+ * Processes an HTML DOM, replacing text content with translated text messages
+ * on elements marked up for translation.  Elements whose class attributes
+ * contain the 'i18n' class name are expected to also have an msgid
+ * attribute. The value of the msgid attributes are looked up as message
+ * IDs and the resulting text is used as the text content of the elements.
+ *
+ * @param {Node} root The root node where the translation should be performed.
+ */
+Msgs.addTranslatedMessagesToDom = function(root) {
+  var elts = root.querySelectorAll('.i18n');
+  for (var i = 0; i < elts.length; i++) {
+    var msgid = elts[i].getAttribute('msgid');
+    if (!msgid) {
+      throw new Error('Element has no msgid attribute: ' + elts[i]);
+    }
+    elts[i].textContent = this.getMsg(msgid);
+    elts[i].classList.add('i18n-processed');
+  }
+};
+
+/**
+ * Retuns a number formatted correctly.
+ *
+ * @param {number} num The number.
+ * @return {string} The number in the correct locale.
+ */
+Msgs.getNumber = function(num) {
+  return '' + num;
+};
+
+/**
+ * Gets a localized display name for a locale.
+ * NOTE: Only a subset of locale identifiers are supported.  See the
+ * |CHROMEVOX_LOCALE_DICT| message.
+ * @param {string} locale On the form |ll| or |ll_CC|, where |ll| is
+ *     the language code and |CC| the country code.
+ * @return {string} The display name.
+ */
+Msgs.getLocaleDisplayName = function(locale) {
+  if (!Msgs.localeNameDict_) {
+    Msgs.localeNameDict_ = /** @type {!Object<string>} */(
+        JSON.parse(this.getMsg('locale_dict')));
+  }
+  var name = Msgs.localeNameDict_[locale];
+  if (!name) {
+    throw Error('Unsupported locale identifier: ' + locale);
+  }
+  return name;
+};
+
+/**
+ * Strings that are displayed in the user interface but don't need
+ * be translated.
+ * @type {Object<string>}
+ */
+Msgs.Untranslated = {
+  /** The unchecked state for a checkbox in braille. */
+  CHECKBOX_UNCHECKED_STATE_BRL: '( )',
+  /** The checked state for a checkbox in braille. */
+  CHECKBOX_CHECKED_STATE_BRL: '(x)',
+  /** The unselected state for a radio button in braille. */
+  RADIO_UNSELECTED_STATE_BRL: '( )',
+  /** The selected state for a radio button in braille. */
+  RADIO_SELECTED_STATE_BRL: '(x)',
+  /** Brailled after a menu if the menu has a submenu. */
+  ARIA_HAS_SUBMENU_BRL: '->',
+  /** Describes an element with the ARIA role option. */
+  ROLE_OPTION: ' ',
+  /** Braille of element with the ARIA role option. */
+  ROLE_OPTION_BRL: ' ',
+  /** Braille of element with the ARIA attribute aria-checked=true. */
+  ARIA_CHECKED_TRUE_BRL: '(x)',
+  /** Braille of element with the ARIA attribute aria-checked=false. */
+  ARIA_CHECKED_FALSE_BRL: '( )',
+  /** Braille of element with the ARIA attribute aria-checked=mixed. */
+  ARIA_CHECKED_MIXED_BRL: '(-)',
+  /** Braille of element with the ARIA attribute aria-disabled=true. */
+  ARIA_DISABLED_TRUE_BRL: 'xx',
+  /** Braille of element with the ARIA attribute aria-expanded=true. */
+  ARIA_EXPANDED_TRUE_BRL: '-',
+  /** Braille of element with the ARIA attribute aria-expanded=false. */
+  ARIA_EXPANDED_FALSE_BRL: '+',
+  /** Braille of element with the ARIA attribute aria-invalid=true. */
+  ARIA_INVALID_TRUE_BRL: '!',
+  /** Braille of element with the ARIA attribute aria-pressed=true. */
+  ARIA_PRESSED_TRUE_BRL: '=',
+  /** Braille of element with the ARIA attribute aria-pressed=false. */
+  ARIA_PRESSED_FALSE_BRL: ' ',
+  /** Braille of element with the ARIA attribute aria-pressed=mixed. */
+  ARIA_PRESSED_MIXED_BRL: '-',
+  /** Braille of element with the ARIA attribute aria-selected=true. */
+  ARIA_SELECTED_TRUE_BRL: '(x)',
+  /** Braille of element with the ARIA attribute aria-selected=false. */
+  ARIA_SELECTED_FALSE_BRL: '( )',
+  /** Brailled after a menu if it has a submenu. */
+  HAS_SUBMENU_BRL: '->',
+  /** Brailled to describe a &lt;time&gt; tag. */
+  TAG_TIME_BRL: ' ',
+};