gitbook/lib/utils/i18n.js

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({
                direction: "ltr"
            }, 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 langSecond = _.last(lang.split("-"));

    var localeMain = _.first(locale.split("-"));
    var localeSecond = _.last(locale.split("-"));

    if (locale == lang) return 100;
    if (localeMain == langMain) return 50;
    if (localeSecond == langSecond) return 20;
    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)
            }
        })
        .filter(function(lang) {
            return lang.score > 0;
        })
        .sortBy("score")
        .pluck("locale")
        .last()
        .value();
    return language || lang;
});

module.exports = {
    getLocales: getLocales,
    getLanguages: getLanguages,
    getByLanguage: getByLanguage,
    normalizeLanguage: normalizeLanguage
};