7 files changed, 146 insertions, 22 deletions

diff --git a/packages/main/esbuild.config.js b/packages/main/esbuild.config.js
index 996ec5a..ae8565d 100644
--- a/packages/main/esbuild.config.js
+++ b/packages/main/esbuild.config.js
@@ -1,9 +1,15 @@
+import { readdir } from 'node:fs/promises';
+import path from 'node:path';
+
 import getRepoInfo from 'git-repo-info';
 
 import { node } from '../../config/buildConstants.js';
 import fileUrlToDirname from '../../config/fileUrlToDirname.js';
 import getEsbuildConfig from '../../config/getEsbuildConfig.js';
 
+/** @type {string} */
+const thisDir = fileUrlToDirname(import.meta.url);
+
 const externalPackages = ['electron'];
 
 if (process.env.MODE !== 'development') {
@@ -12,9 +18,12 @@ if (process.env.MODE !== 'development') {
 
 const gitInfo = getRepoInfo();
 
+/** @type {string[]} */
+const locales = await readdir(path.join(thisDir, '../../locales'));
+
 export default getEsbuildConfig(
   {
-    absWorkingDir: fileUrlToDirname(import.meta.url),
+    absWorkingDir: thisDir,
     entryPoints: ['src/index.ts'],
     outfile: 'dist/index.cjs',
     format: 'cjs',
@@ -27,5 +36,6 @@ export default getEsbuildConfig(
     GIT_SHA: gitInfo.abbreviatedSha,
     GIT_BRANCH: gitInfo.branch,
     BUILD_DATE: Date.now(),
+    SUPPORTED_LOCALES: locales,
   },
 );
diff --git a/packages/main/package.json b/packages/main/package.json
index 491e83a..c84816d 100644
--- a/packages/main/package.json
+++ b/packages/main/package.json
@@ -23,6 +23,7 @@
     "mobx-state-tree": "^5.1.3",
     "ms": "^2.1.3",
     "nanoid": "^3.3.2",
+    "os-locale": "^6.0.2",
     "os-name": "^5.0.1",
     "slug": "^5.3.0"
   },
diff --git a/packages/main/src/i18n/loadLocalization.ts b/packages/main/src/i18n/loadLocalization.ts
index ec3cf84..0413373 100644
--- a/packages/main/src/i18n/loadLocalization.ts
+++ b/packages/main/src/i18n/loadLocalization.ts
@@ -18,33 +18,31 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-import { fallbackLng } from '@sophie/shared';
+import { FALLBACK_LOCALE } from '@sophie/shared';
 import i18next from 'i18next';
 import { autorun } from 'mobx';
 import { addDisposer } from 'mobx-state-tree';
 
-import type Resources from '../infrastructure/resources/Resources';
 import type MainStore from '../stores/MainStore';
 import { getLogger } from '../utils/log';
 
 import I18nStore from './I18nStore';
+import LocatlizationRepository from './LocalizationRepository';
 import RepositoryBasedI18nBackend from './RepositoryBasedI18nBackend';
 import i18nLog from './i18nLog';
-import LocalizationFiles from './impl/LocaltizationFiles';
 
 const log = getLogger('loadLocationzation');
 
 export default async function loadLocalization(
   store: MainStore,
-  resources: Resources,
+  repository: LocatlizationRepository,
   devMode: boolean,
 ): Promise<void> {
-  const repository = new LocalizationFiles(resources);
   const backend = new RepositoryBasedI18nBackend(repository, devMode);
   const i18n = i18next
     .createInstance({
       lng: store.shared.language,
-      fallbackLng,
+      fallbackLng: [FALLBACK_LOCALE],
       debug: devMode,
       saveMissing: devMode,
     })
@@ -58,6 +56,7 @@ export default async function loadLocalization(
       shared: { language },
     } = store;
     if (i18n.language !== language) {
+      log.debug('Setting language', language);
       i18n.changeLanguage(language).catch((error) => {
         log.error('Failed to change language', error);
       });
diff --git a/packages/main/src/i18n/synchronizeLocalizationSettings.ts b/packages/main/src/i18n/synchronizeLocalizationSettings.ts
new file mode 100644
index 0000000..971a593
--- /dev/null
+++ b/packages/main/src/i18n/synchronizeLocalizationSettings.ts
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C)  2022 Kristóf Marussy <kristof@marussy.com>
+ *
+ * This file is part of Sophie.
+ *
+ * Sophie is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { FALLBACK_LOCALE, SYSTEM_LOCALE } from '@sophie/shared';
+import { reaction } from 'mobx';
+import { addDisposer } from 'mobx-state-tree';
+
+import type MainStore from '../stores/MainStore';
+import { getLogger } from '../utils/log';
+
+const log = getLogger('synchronizeLocalizationSettings');
+
+export const TEST_LOCALE = 'cimode';
+
+/**
+ * Finds the closes requested supported language for the requested one.
+ *
+ * If `language` is supported, this function will return it.
+ * Otherwise, it returns a supported language with the same ISO639 code but
+ * no country code (e.g., `en` for `en-GB`) if it exists.
+ * If no supported language matches, `FALLBACK_LOCALE` will be returned.
+ *
+ * @param language The requested language.
+ * @param supportedLanguages  The set of supported languages.
+ * @returns The language to load.
+ */
+function getMatchingLocale(
+  language: string,
+  supportedLanguages: Set<string>,
+): string {
+  // Also let the test locale (i.e., show localization keys directly) through.
+  if (language === TEST_LOCALE || supportedLanguages.has(language)) {
+    return language;
+  }
+  const separatorIndex = language.indexOf('-');
+  if (separatorIndex < 0) {
+    return FALLBACK_LOCALE;
+  }
+  const iso639 = language.slice(0, Math.max(0, separatorIndex));
+  if (supportedLanguages.has(iso639)) {
+    return iso639;
+  }
+  return FALLBACK_LOCALE;
+}
+
+export async function synchronizeLocalizationSettings(
+  store: MainStore,
+  supportedLanguages: string[],
+  osLocale: () => Promise<string>,
+): Promise<void> {
+  const { settings, shared } = store;
+  const supportedLangaugesSet = new Set(supportedLanguages);
+  const setLanguageAsync = async (languageSetting: string) => {
+    const requestedLanguage =
+      languageSetting === SYSTEM_LOCALE ? await osLocale() : languageSetting;
+    const matchingLanguage = getMatchingLocale(
+      requestedLanguage,
+      supportedLangaugesSet,
+    );
+    log.debug(
+      'Setting language',
+      matchingLanguage,
+      'for requested language',
+      requestedLanguage,
+    );
+    shared.setLanguage(matchingLanguage);
+  };
+  const disposer = reaction(
+    () => settings.language,
+    (languageSetting) => {
+      setLanguageAsync(languageSetting).catch((error) => {
+        log.error('Failed to update language', error);
+      });
+    },
+    {
+      fireImmediately: false,
+    },
+  );
+  addDisposer(store, disposer);
+  // Make sure that the language is already set when we resolve.
+  await setLanguageAsync(settings.language);
+}
diff --git a/packages/main/src/initReactions.ts b/packages/main/src/initReactions.ts
index cdff551..b383c8f 100644
--- a/packages/main/src/initReactions.ts
+++ b/packages/main/src/initReactions.ts
@@ -19,8 +19,11 @@
  */
 
 import { app, session } from 'electron';
+import { osLocale } from 'os-locale';
 
+import LocalizationFiles from './i18n/impl/LocaltizationFiles';
 import loadLocalization from './i18n/loadLocalization';
+import { synchronizeLocalizationSettings } from './i18n/synchronizeLocalizationSettings';
 import ConfigFile from './infrastructure/config/impl/ConfigFile';
 import UserAgents from './infrastructure/electron/UserAgents';
 import ElectronViewFactory from './infrastructure/electron/impl/ElectronViewFactory';
@@ -44,28 +47,36 @@ export default async function initReactions(
     store.shared,
     configRepository,
   );
+  const resources = getDistResources(devMode);
+  const localizationLoaded = (async () => {
+    const localizationFiles = new LocalizationFiles(resources);
+    await synchronizeLocalizationSettings(
+      store,
+      import.meta.env.SUPPORTED_LOCALES,
+      osLocale,
+    );
+    await loadLocalization(store, localizationFiles, devMode);
+  })();
+  // Ideally, we would the the chromium `--lang` here,
+  // but `app.isReady()` is often already `true`, so we're too late to do that.
   await app.whenReady();
   const disposeNativeThemeController = synchronizeNativeTheme(store.shared);
-  const resources = getDistResources(devMode);
   hardenSession(resources, devMode, session.defaultSession);
-  if (devMode) {
-    await installDevToolsExtensions();
-  }
   const userAgents = new UserAgents(app.userAgentFallback);
   app.userAgentFallback = userAgents.fallbackUserAgent(devMode);
-  const localizeInterface = async () => {
-    await loadLocalization(store, resources, devMode);
-    setApplicationMenu(store, devMode, isMac);
-  };
-  const localization = localizeInterface();
+  const devToolsLoaded = devMode
+    ? installDevToolsExtensions()
+    : Promise.resolve();
   const viewFactory = new ElectronViewFactory(userAgents, resources, devMode);
-  const [mainWindow] = await Promise.all([
-    viewFactory.createMainWindow(store),
-    viewFactory.loadServiceInject(),
-  ]);
-  store.setMainWindow(mainWindow);
+  const mainWindow = (async () => {
+    await localizationLoaded;
+    setApplicationMenu(store, devMode, isMac);
+    await devToolsLoaded;
+    return viewFactory.createMainWindow(store);
+  })();
+  await viewFactory.loadServiceInject();
   loadServices(store, viewFactory);
-  await localization;
+  store.setMainWindow(await mainWindow);
   return () => {
     disposeNativeThemeController();
     disposeConfigController();
diff --git a/packages/main/src/stores/SharedStore.ts b/packages/main/src/stores/SharedStore.ts
index 67d58d6..960b65e 100644
--- a/packages/main/src/stores/SharedStore.ts
+++ b/packages/main/src/stores/SharedStore.ts
@@ -64,6 +64,9 @@ const SharedStore = defineSharedStoreModel(GlobalSettings, Profile, Service)
     loadConfig(config: Config): void {
       loadConfig(self, config);
     },
+    setLanguage(langauge: string): void {
+      self.language = langauge;
+    },
     setShouldUseDarkColors(shouldUseDarkColors: boolean): void {
       self.shouldUseDarkColors = shouldUseDarkColors;
     },
diff --git a/packages/main/types/importMeta.d.ts b/packages/main/types/importMeta.d.ts
index 7426961..9818ca1 100644
--- a/packages/main/types/importMeta.d.ts
+++ b/packages/main/types/importMeta.d.ts
@@ -7,5 +7,6 @@ interface ImportMeta {
     GIT_SHA: string;
     GIT_BRANCH: string;
     BUILD_DATE: number;
+    SUPPORTED_LOCALES: string[];
   };
 }