import { RX_STRIP_LOCALE_MODS } from '../constants/regex';
import { arrayIncludes } from './array';
import { toString } from './string';

// Localization utilities

// Languages that are RTL
const RTL_LANGS = ['ar', 'az', 'ckb', 'fa', 'he', 'ks', 'lrc', 'mzn', 'ps', 'sd', 'te', 'ug', 'ur', 'yi'].map(locale => locale.toLowerCase());

// Returns true if the locale is RTL
const isLocaleRTL = locale => {
  // Determines if the locale is RTL (only single locale supported)
  const parts = toString(locale).toLowerCase().replace(RX_STRIP_LOCALE_MODS, '').split('-');
  const locale1 = parts.slice(0, 2).join('-');
  const locale2 = parts[0];
  return arrayIncludes(RTL_LANGS, locale1) || arrayIncludes(RTL_LANGS, locale2);
};

export { isLocaleRTL };
