/*
 * Copyright (c) 1999, 2005, 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.awt.motif;

import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.*;
import static sun.awt.motif.DoubleByte.*;

public class X11GBK extends Charset {

    private static Charset gbk = Charset.forName("GBK");

    public X11GBK () {
        super("X11GBK", null);
    }
    public CharsetEncoder newEncoder() {
        return new Encoder(this);
    }
    public CharsetDecoder newDecoder() {
        return gbk.newDecoder();
    }

    public boolean contains(Charset cs) {
        return cs instanceof X11GBK;
    }

    static class Encoder extends CharsetEncoder {

        static final int MAX_SINGLEBYTE = 0xff;
        static private CharsetEncoder enc = gbk.newEncoder();

        Encoder(Charset cs) {
            super(cs, enc.averageBytesPerChar(), enc.maxBytesPerChar(),
                  enc.replacement());
            enc.onMalformedInput(CodingErrorAction.REPORT);
            enc.onUnmappableCharacter(CodingErrorAction.REPORT);
        }

        public boolean canEncode(char ch){
            if (ch < 0x80) return false;
            return enc.canEncode(ch);
        }

        public int encodeChar(char ch) {
            if (ch < 0x80) {
                return UNMAPPABLE_ENCODING;
            }
            char[] buf = new char[1];
            buf[0] = ch;
            ByteBuffer bb = null;
            CharBuffer cb = CharBuffer.wrap(buf);
            boolean mapped = false;
            try {
                bb = enc.encode(cb);
                mapped = true;
            } catch (CharacterCodingException cce) {
            }
            if (mapped && bb != null) {
                int ret = UNMAPPABLE_ENCODING;
                if (bb.remaining() == 1) {
                   ret = bb.get() & 0xff;
                } else if (bb.remaining() > 1) {
                   ret = ((bb.get() & 0xff) << 8) | (bb.get() & 0xff);
                }
                return ret;
            } else {
                return UNMAPPABLE_ENCODING;
            }
        }

        private SurrogateParser sgp;
        protected CoderResult encodeLoop(CharBuffer src, ByteBuffer dst) {
            int mark = src.position();
            try {
                while (src.hasRemaining()) {
                    char c = src.get();
                    int bb = encodeChar(c);
                    if (bb == UNMAPPABLE_ENCODING) {
                        if (Character.isSurrogate(c)) {
                            if (sgp == null) {
                                sgp = new SurrogateParser();
                            }
                            if (sgp.parse(c, src) < 0)
                                return sgp.error();
                            return sgp.unmappableResult();
                        }
                        return CoderResult.unmappableForLength(1);
                    }
                    if (bb > MAX_SINGLEBYTE) {  // DoubleByte
                        if (dst.remaining() < 2)
                            return CoderResult.OVERFLOW;
                        dst.put((byte)(bb >> 8));
                        dst.put((byte)(bb));
                    } else {
                        if (dst.remaining() < 1)
                        return CoderResult.OVERFLOW;
                        dst.put((byte)bb);
                    }
                    mark++;
                }
                return CoderResult.UNDERFLOW;
            } finally {
                src.position(mark);
            }

        }
    }
}