Files
outline/app/utils/language.ts
2025-11-11 19:35:57 -05:00

95 lines
2.6 KiB
TypeScript

import { i18n } from "i18next";
import { locales, unicodeCLDRtoBCP47 } from "@shared/utils/date";
import Desktop from "./Desktop";
/**
* Formats a number using the user's locale where possible. Use `useFormatNumber` hook
* instead of this function in React components, to automatically use the user's locale.
*
* @param number The number to format
* @param locale The locale to use for formatting (BCP47 format)
* @returns The formatted number as a string
*/
export function formatNumber(number: number, locale: string) {
try {
return new Intl.NumberFormat(locale).format(number);
} catch (_err) {
return number.toString();
}
}
/**
* Detects the user's language based on the browser's language settings.
*
* @returns The user's language in CLDR format (en_US)
*/
export function detectLanguage() {
const [ln, r] = navigator.language.split("-");
const region = (r || ln).toUpperCase();
return `${ln}_${region}` as keyof typeof locales;
}
/**
* Changes the language of the app, and updates the spellchecker language
* if running in the desktop shell.
*
* @param locale The locale to change to, in CLDR format (en_US)
* @param instance The i18n instance to use
*/
export async function changeLanguage(
locale: string | null | undefined,
instance: i18n
) {
// Languages are stored in en_US format in the database, however the
// frontend translation framework (i18next) expects en-US
const localeBCP = locale ? unicodeCLDRtoBCP47(locale) : undefined;
if (localeBCP && instance.languages?.[0] !== localeBCP) {
await instance.changeLanguage(localeBCP);
await Desktop.bridge?.setSpellCheckerLanguages(["en-US", localeBCP]);
}
}
/**
* Languages with special styling, in ISO 639-1 format.
*/
const scriptsWithLang = new Set([
"th", // Thai
"lo", // Lao
"km", // Khmer
"my", // Burmese
"hi", // Hindi
"mr", // Marathi
"ne", // Nepali
"bn", // Bengali
"gu", // Gujarati
"pa", // Punjabi
"te", // Telugu
"ta", // Tamil
"ml", // Malayalam
"si", // Sinhala
"bo", // Tibetan
"ar", // Arabic
"fa", // Persian
"ur", // Urdu
"he", // Hebrew
"am", // Amharic
"mn", // Mongolian
]);
/**
* Returns the language code if it requires special text styling, otherwise undefined.
* This is used to determine if a lang attribute should be set on elements for CSS styling.
*
* @param langCode The language code to check, in ISO 639-1 format
* @returns The language code if it requires special styling, otherwise undefined
*/
export function getLangFor(
langCode: string | null | undefined
): string | undefined {
if (!langCode) {
return undefined;
}
return scriptsWithLang.has(langCode) ? langCode : undefined;
}