/*

 * Copyright (c) 2002, 2006, 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

 * questions.

 */

/*

 */

package sun.nio.cs.ext;

import java.nio.charset.Charset;

import java.nio.ByteBuffer;

import java.nio.CharBuffer;

import java.nio.charset.CharsetDecoder;

import java.nio.charset.CharsetEncoder;

import java.nio.charset.CoderResult;

import sun.nio.cs.HistoricallyNamedCharset;

public class ISO2022_CN_CNS extends ISO2022 implements HistoricallyNamedCharset

{

    public ISO2022_CN_CNS() {

        super("x-ISO-2022-CN-CNS", ExtendedCharsets.aliasesFor("x-ISO-2022-CN-CNS"));

    }

    public boolean contains(Charset cs) {

        // overlapping repertoire of EUC_TW, CNS11643

        return ((cs instanceof EUC_TW) ||

                (cs.name().equals("US-ASCII")) ||

                (cs instanceof ISO2022_CN_CNS));

    }

    public String historicalName() {

        return "ISO2022CN_CNS";

    }

    public CharsetDecoder newDecoder() {

        return new ISO2022_CN.Decoder(this);

    }

    public CharsetEncoder newEncoder() {

        return new Encoder(this);

    }

    private static class Encoder extends ISO2022.Encoder {

        public Encoder(Charset cs)

        {

            super(cs);

            SODesig = "$)G";

            SS2Desig = "$*H";

            SS3Desig = "$+I";

            try {

                Charset cset = Charset.forName("EUC_TW"); // CNS11643

                ISOEncoder = cset.newEncoder();

            } catch (Exception e) { }

        }

        private byte[] bb = new byte[4];

        public boolean canEncode(char c) {

            int n = 0;

            return (c <= '\u007f' ||

                    (n = ((EUC_TW.Encoder)ISOEncoder).toEUC(c, bb)) == 2 ||

                    (n == 4 && bb[0] == SS2 &&

                     (bb[1] == PLANE2 || bb[1] == PLANE3)));

        }

        /*

         * Since ISO2022-CN-CNS possesses a CharsetEncoder

         * without the corresponding CharsetDecoder half the

         * default replacement check needs to be overridden

         * since the parent class version attempts to

         * decode 0x3f (?).

         */

        public boolean isLegalReplacement(byte[] repl) {

            // 0x3f is OK as the replacement byte

            return (repl.length == 1 && repl[0] == (byte) 0x3f);

        }

    }

}