Improve i18n to support locale normalization

lib/configuration.js

@@ -5,6 +5,7 @@ var semver = require('semver');
 
 var pkg = require('../package.json');
 var fs = require("./utils/fs");
+var i18n = require("./utils/i18n");
 
 // Default plugins added to each books
 var defaultsPlugins = [];
@@ -124,7 +125,7 @@ Configuration.prototype.getStructure = function(name) {
 
 // Return normalized language
 Configuration.prototype.normalizeLanguage = function() {
-    return _.first(this.options.language.split("-")).toLowerCase();
+    return i18n.normalizeLanguage(this.options.language);
 };
 
 

lib/generators/website.js

@@ -12,6 +12,7 @@ var fs = require("../utils/fs");
 var BaseGenerator = require("../generator");
 var links = require("../utils/links");
 var pageUtil = require("../utils/page");
+var i18n = require("../utils/i18n");
 
 var pkg = require("../../package.json");
 
@@ -74,20 +75,12 @@ Generator.prototype.prepareTemplates = function() {
 Generator.prototype.prepareTemplateEngine = function() {
     var that = this;
 
-    return fs.readdir(path.resolve(__dirname, "../../theme/i18n"))
-    .then(function(locales) {
+    return Q()
+    .then(function() {
         var language = that.book.config.normalizeLanguage();
 
-        locales = _.chain(locales)
-            .map(function(local) {
-                local = path.basename(local, ".json");
-                return [local, require("../../theme/i18n/"+local)];
-            })
-            .object()
-            .value();
-
-        if (!_.contains(_.keys(locales), language) && language != "en") {
-            that.book.log.warn.ln("Language '"+language+"' is not available as a layout locales (en, "+_.keys(locales).join(", ")+")");
+        if (!i18n.getByLanguage(language) && language != "en") {
+            that.book.log.warn.ln("Language '"+language+"' is not available as a layout locales (en, "+i18n.getLanguages().join(", ")+")");
         }
 
         var folders = _.chain(that.templates)
@@ -114,7 +107,7 @@ Generator.prototype.prepareTemplateEngine = function() {
         that.env.addExtension('FilterExtension', new FilterExtension(that.env));
         that.env.addExtension('I18nExtension', new I18nExtension({
             env: that.env,
-            translations: locales,
+            translations: i18n.getLocales(),
             locale: "language"
         }));
     });

lib/utils/i18n.js

@@ -0,0 +1,63 @@
+var _ = require("lodash");
+var path = require("path");
+var fs = require("fs");
+
+var I18N_PATH = path.resolve(__dirname, "../../theme/i18n/")
+
+var getLocales = _.memoize(function() {
+	var locales = fs.readdirSync(I18N_PATH);
+	return _.chain(locales)
+        .map(function(local) {
+            local = path.basename(local, ".json");
+            return [local, _.extend(require(path.join(I18N_PATH, local)), {
+            	id: local
+            })];
+        })
+        .object()
+        .value();
+});
+
+var getLanguages = function() {
+	return _.keys(getLocales());
+};
+
+var getByLanguage = function(lang) {
+	lang = normalizeLanguage(lang);
+	var locales = getLocales();
+	return locales[lang];
+};
+
+var compareLocales = function(lang, locale) {
+	var langMain = _.first(lang.split("-"));
+	var localeMain = _.first(locale.split("-"));
+
+	if (locale == lang) return 100;
+	if (localeMain == langMain) return 50;
+	return 0;
+};
+
+var normalizeLanguage = _.memoize(function(lang) {
+	var locales = getLocales();
+	var language = _.chain(locales)
+		.values()
+		.map(function(locale) {
+			locale = locale.id;
+
+			return {
+				locale: locale,
+				score: compareLocales(lang, locale)
+			}
+		})
+		.sortBy("score")
+		.pluck("locale")
+		.last()
+		.value();
+	return language || lang;
+});
+
+module.exports = {
+	getLocales: getLocales,
+	getLanguages: getLanguages,
+	getByLanguage: getByLanguage,
+	normalizeLanguage: normalizeLanguage
+};