signal-desktop/app/locale.ts

99 lines
2.6 KiB
TypeScript

// Copyright 2017 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
import { join } from 'path';
import { readFileSync } from 'fs';
import { merge } from 'lodash';
import { setupI18n } from '../ts/util/setupI18n';
import type { LoggerType } from '../ts/types/Logging';
import type { LocaleMessagesType } from '../ts/types/I18N';
import type { LocalizerType } from '../ts/types/Util';
function removeRegion(locale: string): string {
const match = /^([^-]+)(-.+)$/.exec(locale);
if (match) {
return match[1];
}
return locale;
}
function getLocaleMessages(locale: string): LocaleMessagesType {
const targetFile = join(__dirname, '..', '_locales', locale, 'messages.json');
return JSON.parse(readFileSync(targetFile, 'utf-8'));
}
export type LocaleType = {
i18n: LocalizerType;
name: string;
messages: LocaleMessagesType;
};
function finalize(
messages: LocaleMessagesType,
backupMessages: LocaleMessagesType,
localeName: string
) {
// We start with english, then overwrite that with anything present in locale
const finalMessages = merge(backupMessages, messages);
const i18n = setupI18n(localeName, finalMessages);
return {
i18n,
name: localeName,
messages: finalMessages,
};
}
export function load({
preferredSystemLocales,
logger,
}: {
preferredSystemLocales: Array<string>;
logger: Pick<LoggerType, 'error' | 'warn' | 'info'>;
}): LocaleType {
if (preferredSystemLocales == null) {
throw new TypeError('`preferredSystemLocales` is required');
}
if (!logger || !logger.error) {
throw new TypeError('`logger.error` is required');
}
if (!logger.warn) {
throw new TypeError('`logger.warn` is required');
}
if (preferredSystemLocales.length === 0) {
logger.warn('`preferredSystemLocales` was empty');
}
const english = getLocaleMessages('en');
for (const locale of preferredSystemLocales) {
try {
logger.info(`Loading preferred system locale: '${locale}'`);
return finalize(getLocaleMessages(locale), english, locale);
} catch (e) {
logger.warn(
`Problem loading messages for locale '${locale}', ${e.toString()}`
);
}
const languageOnly = removeRegion(locale);
try {
logger.warn(`Falling back to parent language: '${languageOnly}'`);
// Note: messages are from parent language, but we still keep the region
return finalize(getLocaleMessages(languageOnly), english, locale);
} catch (e) {
logger.error(
`Problem loading messages for parent locale '${languageOnly}'`
);
}
}
logger.warn("Falling back to 'en' locale");
return finalize(english, english, 'en');
}