/**

* Jooby https://jooby.io

* Apache License Version 2.0 https://jooby.io/LICENSE.txt

* Copyright 2014 Edgar Espina

*/

package io.jooby.internal;

import java.util.List;

import java.util.Locale;

import java.util.Optional;

import static java.util.Comparator.comparing;

import static java.util.stream.Collectors.toList;

public class LocaleUtils {

public static Optional<List<Locale.LanguageRange>> parseRanges(final String value) {

if (value == null) {

return Optional.empty();

}

// remove trailing ';' well-formed vs ill-formed

String wellFormed = value;

if (wellFormed.endsWith(";")) {

wellFormed = wellFormed.substring(0, wellFormed.length() - 1);

}

try {

return Optional.of(Locale.LanguageRange.parse(wellFormed)

.stream()

.sorted(comparing(Locale.LanguageRange::getWeight).reversed())

.collect(toList()));

} catch (IllegalArgumentException e) {

return Optional.empty();

}

}

public static Optional<List<Locale>> parseLocales(final String value) {

return parseRanges(value).map(l -> l.stream()

.map(r -> Locale.forLanguageTag(r.getRange()))

.collect(toList()));

}

}