/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package org.mozilla.gecko.util;

import android.text.TextUtils;
import java.util.Locale;

public class LocaleUtils {
  /**
   * Function normalizes BCP-47 language tags to use non-legacy language codes and only return
   * 'language-region' style codes for use with Accept-Language and Requested Locales.
   *
   * <p>Locale.getLanguage() may return legacy language code until Java 17
   * https://developer.android.com/reference/java/util/Locale#legacy_language_codes
   *
   * @param locale The BCP-47 locale to normalize. e.g., iw-IL, zn-Hans-CN, en-US-u-mu-celsius,
   * @return A normalized BCP-47 language code with only language-region, e.g., he-IL, zn-CN, en-US.
   */
  public static String getLanguageRegionLocale(final Locale locale) {
    String language = locale.getLanguage();
    if (language.equals("in")) {
      language = "id";
    } else if (language.equals("iw")) {
      language = "he";
    } else if (language.equals("ji")) {
      language = "yi";
    }
    final StringBuilder out = new StringBuilder(language);
    final String country = locale.getCountry();
    if (!TextUtils.isEmpty(country)) {
      out.append('-').append(country);
    }
    // e.g. "en", "en-US"
    return out.toString();
  }
}