michael@0: /* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
michael@0: /* globals FirefoxCom */
michael@0: 
michael@0: 'use strict';
michael@0: 
michael@0: // Small subset of the webL10n API by Fabien Cazenave for pdf.js extension.
michael@0: (function(window) {
michael@0:   var gLanguage = '';
michael@0: 
michael@0:   // fetch an l10n objects
michael@0:   function getL10nData(key) {
michael@0:     var response = FirefoxCom.requestSync('getStrings', key);
michael@0:     var data = JSON.parse(response);
michael@0:     if (!data) {
michael@0:       console.warn('[l10n] #' + key + ' missing for [' + gLanguage + ']');
michael@0:     }
michael@0:     return data;
michael@0:   }
michael@0: 
michael@0:   // replace {{arguments}} with their values
michael@0:   function substArguments(text, args) {
michael@0:     if (!args) {
michael@0:       return text;
michael@0:     }
michael@0:     return text.replace(/\{\{\s*(\w+)\s*\}\}/g, function(all, name) {
michael@0:       return (name in args ? args[name] : '{{' + name + '}}');
michael@0:     });
michael@0:   }
michael@0: 
michael@0:   // translate a string
michael@0:   function translateString(key, args, fallback) {
michael@0:     var i = key.lastIndexOf('.');
michael@0:     var name, property;
michael@0:     if (i >= 0) {
michael@0:       name = key.substring(0, i);
michael@0:       property = key.substring(i + 1);
michael@0:     } else {
michael@0:       name = key;
michael@0:       property = 'textContent';
michael@0:     }
michael@0:     var data = getL10nData(name);
michael@0:     var value = (data && data[property]) || fallback;
michael@0:     if (!value) {
michael@0:       return '{{' + key + '}}';
michael@0:     }
michael@0:     return substArguments(value, args);
michael@0:   }
michael@0: 
michael@0:   // translate an HTML element
michael@0:   function translateElement(element) {
michael@0:     if (!element || !element.dataset) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // get the related l10n object
michael@0:     var key = element.dataset.l10nId;
michael@0:     var data = getL10nData(key);
michael@0:     if (!data) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // get arguments (if any)
michael@0:     // TODO: more flexible parser?
michael@0:     var args;
michael@0:     if (element.dataset.l10nArgs) {
michael@0:       try {
michael@0:         args = JSON.parse(element.dataset.l10nArgs);
michael@0:       } catch (e) {
michael@0:         console.warn('[l10n] could not parse arguments for #' + key + '');
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     // translate element
michael@0:     // TODO: security check?
michael@0:     for (var k in data) {
michael@0:       element[k] = substArguments(data[k], args);
michael@0:     }
michael@0:   }
michael@0: 
michael@0: 
michael@0:   // translate an HTML subtree
michael@0:   function translateFragment(element) {
michael@0:     element = element || document.querySelector('html');
michael@0: 
michael@0:     // check all translatable children (= w/ a `data-l10n-id' attribute)
michael@0:     var children = element.querySelectorAll('*[data-l10n-id]');
michael@0:     var elementCount = children.length;
michael@0:     for (var i = 0; i < elementCount; i++) {
michael@0:       translateElement(children[i]);
michael@0:     }
michael@0: 
michael@0:     // translate element itself if necessary
michael@0:     if (element.dataset.l10nId) {
michael@0:       translateElement(element);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   window.addEventListener('DOMContentLoaded', function() {
michael@0:     gLanguage = FirefoxCom.requestSync('getLocale', null);
michael@0: 
michael@0:     translateFragment();
michael@0: 
michael@0:     // fire a 'localized' DOM event
michael@0:     var evtObject = document.createEvent('Event');
michael@0:     evtObject.initEvent('localized', false, false);
michael@0:     evtObject.language = gLanguage;
michael@0:     window.dispatchEvent(evtObject);
michael@0:   });
michael@0: 
michael@0:   // Public API
michael@0:   document.mozL10n = {
michael@0:     // get a localized string
michael@0:     get: translateString,
michael@0: 
michael@0:     // get the document language
michael@0:     getLanguage: function() {
michael@0:       return gLanguage;
michael@0:     },
michael@0: 
michael@0:     // get the direction (ltr|rtl) of the current language
michael@0:     getDirection: function() {
michael@0:       // http://www.w3.org/International/questions/qa-scripts
michael@0:       // Arabic, Hebrew, Farsi, Pashto, Urdu
michael@0:       var rtlList = ['ar', 'he', 'fa', 'ps', 'ur'];
michael@0:       return (rtlList.indexOf(gLanguage) >= 0 ? 'rtl' : 'ltr');
michael@0:     },
michael@0: 
michael@0:     // translate an element or document fragment
michael@0:     translate: translateFragment
michael@0:   };
michael@0: })(this);
michael@0: