app/localization.js

   1 /*
   2  * noVNC: HTML5 VNC client
   3  * Copyright (C) 2012 Joel Martin
   4  * Licensed under MPL 2.0 (see LICENSE.txt)
   5  *
   6  * See README.md for usage and integration instructions.
   7  */
   8
   9 /*
  10  * Localization Utilities
  11  */
  12
  13 export function Localizer() {
  14     // Currently configured language
  15     this.language = 'en';
  16
  17     // Current dictionary of translations
  18     this.dictionary = undefined;
  19 }
  20
  21 Localizer.prototype = {
  22     // Configure suitable language based on user preferences
  23     setup: function (supportedLanguages) {
  24         var userLanguages;
  25
  26         this.language = 'en'; // Default: US English
  27
  28         /*
  29          * Navigator.languages only available in Chrome (32+) and FireFox (32+)
  30          * Fall back to navigator.language for other browsers
  31          */
  32         if (typeof window.navigator.languages == 'object') {
  33             userLanguages = window.navigator.languages;
  34         } else {
  35             userLanguages = [navigator.language || navigator.userLanguage];
  36         }
  37
  38         for (var i = 0;i < userLanguages.length;i++) {
  39             var userLang = userLanguages[i];
  40             userLang = userLang.toLowerCase();
  41             userLang = userLang.replace("_", "-");
  42             userLang = userLang.split("-");
  43
  44             // Built-in default?
  45             if ((userLang[0] === 'en') &&
  46                 ((userLang[1] === undefined) || (userLang[1] === 'us'))) {
  47                 return;
  48             }
  49
  50             // First pass: perfect match
  51             var j;
  52             for (j = 0; j < supportedLanguages.length; j++) {
  53                 var supLang = supportedLanguages[j];
  54                 supLang = supLang.toLowerCase();
  55                 supLang = supLang.replace("_", "-");
  56                 supLang = supLang.split("-");
  57
  58                 if (userLang[0] !== supLang[0])
  59                     continue;
  60                 if (userLang[1] !== supLang[1])
  61                     continue;
  62
  63                 this.language = supportedLanguages[j];
  64                 return;
  65             }
  66
  67             // Second pass: fallback
  68             for (j = 0;j < supportedLanguages.length;j++) {
  69                 supLang = supportedLanguages[j];
  70                 supLang = supLang.toLowerCase();
  71                 supLang = supLang.replace("_", "-");
  72                 supLang = supLang.split("-");
  73
  74                 if (userLang[0] !== supLang[0])
  75                     continue;
  76                 if (supLang[1] !== undefined)
  77                     continue;
  78
  79                 this.language = supportedLanguages[j];
  80                 return;
  81             }
  82         }
  83     },
  84
  85     // Retrieve localised text
  86     get: function (id) {
  87         if (typeof this.dictionary !== 'undefined' && this.dictionary[id]) {
  88             return this.dictionary[id];
  89         } else {
  90             return id;
  91         }
  92     },
  93
  94     // Traverses the DOM and translates relevant fields
  95     // See https://html.spec.whatwg.org/multipage/dom.html#attr-translate
  96     translateDOM: function () {
  97         var self = this;
  98         function process(elem, enabled) {
  99             function isAnyOf(searchElement, items) {
 100                 return items.indexOf(searchElement) !== -1;
 101             }
 102
 103             function translateAttribute(elem, attr) {
 104                 var str = elem.getAttribute(attr);
 105                 str = self.get(str);
 106                 elem.setAttribute(attr, str);
 107             }
 108
 109             function translateTextNode(node) {
 110                 var str = node.data.trim();
 111                 str = self.get(str);
 112                 node.data = str;
 113             }
 114
 115             if (elem.hasAttribute("translate")) {
 116                 if (isAnyOf(elem.getAttribute("translate"), ["", "yes"])) {
 117                     enabled = true;
 118                 } else if (isAnyOf(elem.getAttribute("translate"), ["no"])) {
 119                     enabled = false;
 120                 }
 121             }
 122
 123             if (enabled) {
 124                 if (elem.hasAttribute("abbr") &&
 125                     elem.tagName === "TH") {
 126                     translateAttribute(elem, "abbr");
 127                 }
 128                 if (elem.hasAttribute("alt") &&
 129                     isAnyOf(elem.tagName, ["AREA", "IMG", "INPUT"])) {
 130                     translateAttribute(elem, "alt");
 131                 }
 132                 if (elem.hasAttribute("download") &&
 133                     isAnyOf(elem.tagName, ["A", "AREA"])) {
 134                     translateAttribute(elem, "download");
 135                 }
 136                 if (elem.hasAttribute("label") &&
 137                     isAnyOf(elem.tagName, ["MENUITEM", "MENU", "OPTGROUP",
 138                                    "OPTION", "TRACK"])) {
 139                     translateAttribute(elem, "label");
 140                 }
 141                 // FIXME: Should update "lang"
 142                 if (elem.hasAttribute("placeholder") &&
 143                     isAnyOf(elem.tagName, ["INPUT", "TEXTAREA"])) {
 144                     translateAttribute(elem, "placeholder");
 145                 }
 146                 if (elem.hasAttribute("title")) {
 147                     translateAttribute(elem, "title");
 148                 }
 149                 if (elem.hasAttribute("value") &&
 150                     elem.tagName === "INPUT" &&
 151                     isAnyOf(elem.getAttribute("type"), ["reset", "button", "submit"])) {
 152                     translateAttribute(elem, "value");
 153                 }
 154             }
 155
 156             for (var i = 0;i < elem.childNodes.length;i++) {
 157                 var node = elem.childNodes[i];
 158                 if (node.nodeType === node.ELEMENT_NODE) {
 159                     process(node, enabled);
 160                 } else if (node.nodeType === node.TEXT_NODE && enabled) {
 161                     translateTextNode(node);
 162                 }
 163             }
 164         }
 165
 166         process(document.body, true);
 167     },
 168 };
 169
 170 export var l10n = new Localizer();
 171 export default l10n.get.bind(l10n);