/*

 * Copyright (c) 2010, 2014, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

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 */

/*

 *******************************************************************************

 * Copyright (C) 2009-2010, International Business Machines Corporation and    *

 * others. All Rights Reserved.                                                *

 *******************************************************************************

 */

package sun.util.locale;

import java.util.Collections;

import java.util.Map;

import java.util.Map.Entry;

import java.util.Set;

import java.util.SortedMap;

import java.util.SortedSet;

import java.util.StringJoiner;

public class UnicodeLocaleExtension extends Extension {

    public static final char SINGLETON = 'u';

    private final Set<String> attributes;

    private final Map<String, String> keywords;

    public static final UnicodeLocaleExtension CA_JAPANESE

        = new UnicodeLocaleExtension("ca", "japanese");

    public static final UnicodeLocaleExtension NU_THAI

        = new UnicodeLocaleExtension("nu", "thai");

    private UnicodeLocaleExtension(String key, String value) {

        super(SINGLETON, key + "-" + value);

        attributes = Collections.emptySet();

        keywords = Collections.singletonMap(key, value);

    }

    UnicodeLocaleExtension(SortedSet<String> attributes, SortedMap<String, String> keywords) {

        super(SINGLETON);

        if (attributes != null) {

            this.attributes = attributes;

        } else {

            this.attributes = Collections.emptySet();

        }

        if (keywords != null) {

            this.keywords = keywords;

        } else {

            this.keywords = Collections.emptyMap();

        }

        if (!this.attributes.isEmpty() || !this.keywords.isEmpty()) {

            StringJoiner sj = new StringJoiner(LanguageTag.SEP);

            for (String attribute : this.attributes) {

                sj.add(attribute);

            }

            for (Entry<String, String> keyword : this.keywords.entrySet()) {

                String key = keyword.getKey();

                String value = keyword.getValue();

                sj.add(key);

                if (value.length() > 0) {

                    sj.add(value);

                }

            }

            setValue(sj.toString());

        }

    }

    public Set<String> getUnicodeLocaleAttributes() {

        if (attributes == Collections.EMPTY_SET) {

            return attributes;

        }

        return Collections.unmodifiableSet(attributes);

    }

    public Set<String> getUnicodeLocaleKeys() {

        if (keywords == Collections.EMPTY_MAP) {

            return Collections.emptySet();

        }

        return Collections.unmodifiableSet(keywords.keySet());

    }

    public String getUnicodeLocaleType(String unicodeLocaleKey) {

        return keywords.get(unicodeLocaleKey);

    }

    public static boolean isSingletonChar(char c) {

        return (SINGLETON == LocaleUtils.toLower(c));

    }

    public static boolean isAttribute(String s) {

        // 3*8alphanum

        int len = s.length();

        return (len >= 3) && (len <= 8) && LocaleUtils.isAlphaNumericString(s);

    }

    public static boolean isKey(String s) {

        // 2alphanum

        return (s.length() == 2) && LocaleUtils.isAlphaNumericString(s);

    }

    public static boolean isTypeSubtag(String s) {

        // 3*8alphanum

        int len = s.length();

        return (len >= 3) && (len <= 8) && LocaleUtils.isAlphaNumericString(s);

    }

}