michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: "use strict";
michael@0: 
michael@0: module.metadata = {
michael@0:   "stability": "unstable"
michael@0: };
michael@0: 
michael@0: const { Cc, Ci } = require("chrome");
michael@0: const { getPreferedLocales, findClosestLocale } = require("./locale");
michael@0: const { readURI } = require("../net/url");
michael@0: const { resolve } = require("../core/promise");
michael@0: 
michael@0: function parseJsonURI(uri) {
michael@0:   return readURI(uri).
michael@0:     then(JSON.parse).
michael@0:     then(null, function (error) {
michael@0:       throw Error("Failed to parse locale file:\n" + uri + "\n" + error);
michael@0:     });
michael@0: }
michael@0: 
michael@0: // Returns the array stored in `locales.json` manifest that list available
michael@0: // locales files
michael@0: function getAvailableLocales(rootURI) {
michael@0:   let uri = rootURI + "locales.json";
michael@0:   return parseJsonURI(uri).then(function (manifest) {
michael@0:     return "locales" in manifest &&
michael@0:            Array.isArray(manifest.locales) ?
michael@0:            manifest.locales : [];
michael@0:   });
michael@0: }
michael@0: 
michael@0: // Returns URI of the best locales file to use from the XPI
michael@0: function getBestLocale(rootURI) {
michael@0:   // Read localization manifest file that contains list of available languages
michael@0:   return getAvailableLocales(rootURI).then(function (availableLocales) {
michael@0:     // Retrieve list of prefered locales to use
michael@0:     let preferedLocales = getPreferedLocales();
michael@0: 
michael@0:     // Compute the most preferable locale to use by using these two lists
michael@0:     return findClosestLocale(availableLocales, preferedLocales);
michael@0:   });
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Read localization files and returns a promise of data to put in `@l10n/data`
michael@0:  * pseudo module, in order to allow l10n/json/core to fetch it.
michael@0:  */
michael@0: exports.load = function load(rootURI) {
michael@0:   // First, search for a locale file:
michael@0:   return getBestLocale(rootURI).then(function (bestMatchingLocale) {
michael@0:     // It may be null if the addon doesn't have any locale file
michael@0:     if (!bestMatchingLocale)
michael@0:       return resolve(null);
michael@0: 
michael@0:     let localeURI = rootURI + "locale/" + bestMatchingLocale + ".json";
michael@0: 
michael@0:     // Locale files only contains one big JSON object that is used as
michael@0:     // an hashtable of: "key to translate" => "translated key"
michael@0:     // TODO: We are likely to change this in order to be able to overload
michael@0:     //       a specific key translation. For a specific package, module or line?
michael@0:     return parseJsonURI(localeURI).then(function (json) {
michael@0:       return {
michael@0:         hash: json,
michael@0:         bestMatchingLocale: bestMatchingLocale
michael@0:       };
michael@0:     });
michael@0:   });
michael@0: }