/*

 * Copyright (c) 2001, 2008, 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

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 * questions.

 */

package sun.font;

import java.nio.CharBuffer;

import java.nio.ByteBuffer;

import java.nio.charset.*;

import sun.nio.cs.*;

public abstract class X11CNS11643 extends Charset {

    private final int plane;

    public X11CNS11643 (int plane, String name) {

        super(name, null);

        switch (plane) {

        case 1:

            this.plane = 0; // CS1

            break;

        case 2:

        case 3:

            this.plane = plane;

            break;

        default:

            throw new IllegalArgumentException

                ("Only planes 1, 2, and 3 supported");

        }

    }

    public CharsetEncoder newEncoder() {

        return new Encoder(this, plane);

    }

    public CharsetDecoder newDecoder() {

        return new Decoder(this, plane);

    }

    public boolean contains(Charset cs) {

        return cs instanceof X11CNS11643;

    }

    private class Encoder extends EUC_TW.Encoder {

        private int plane;

        public Encoder(Charset cs, int plane) {

            super(cs);

            this.plane = plane;

        }

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

        public boolean canEncode(char c) {

            if (c <= 0x7F) {

                return false;

            }

            int nb = toEUC(c, bb);

            if (nb == -1)

                return false;

            int p = 0;

            if (nb == 4)

                p = (bb[1] & 0xff) - 0xa0;

            return (p == plane);

        }

        public boolean isLegalReplacement(byte[] repl) {

            return true;

        }

        protected CoderResult encodeLoop(CharBuffer src, ByteBuffer dst) {

            char[] sa = src.array();

            int sp = src.arrayOffset() + src.position();

            int sl = src.arrayOffset() + src.limit();

            byte[] da = dst.array();

            int dp = dst.arrayOffset() + dst.position();

            int dl = dst.arrayOffset() + dst.limit();

            try {

                while (sp < sl) {

                    char c = sa[sp];

                    if ( c > '\u007f'&& c < '\uFFFE') {

                        int nb = toEUC(c, bb);

                        if (nb != -1) {

                            int p = 0;

                            if (nb == 4)

                                p = (bb[1] & 0xff) - 0xa0;

                            if (p == plane) {

                                if (dl - dp < 2)

                                    return CoderResult.OVERFLOW;

                                if (nb == 2) {

                                    da[dp++] = (byte)(bb[0] & 0x7f);

                                    da[dp++] = (byte)(bb[1] & 0x7f);

                                } else {

                                    da[dp++] = (byte)(bb[2] & 0x7f);

                                    da[dp++] = (byte)(bb[3] & 0x7f);

                                }

                                sp++;

                                continue;

                            }

                        }

                    }

                    return CoderResult.unmappableForLength(1);

                }

                return CoderResult.UNDERFLOW;

            } finally {

                src.position(sp - src.arrayOffset());

                dst.position(dp - dst.arrayOffset());

            }

        }

    }

    private class Decoder extends EUC_TW.Decoder {

        int plane;

        private String table;

        protected Decoder(Charset cs, int plane) {

            super(cs);

            if (plane == 0)

                this.plane = plane;

            else if (plane == 2 || plane == 3)

                this.plane = plane - 1;

            else

                throw new IllegalArgumentException

                    ("Only planes 1, 2, and 3 supported");

        }

        //we only work on array backed buffer.

        protected CoderResult decodeLoop(ByteBuffer src, CharBuffer dst) {

            byte[] sa = src.array();

            int sp = src.arrayOffset() + src.position();

            int sl = src.arrayOffset() + src.limit();

            char[] da = dst.array();

            int dp = dst.arrayOffset() + dst.position();

            int dl = dst.arrayOffset() + dst.limit();

            try {

                while (sp < sl) {

                    if ( sl - sp < 2) {

                        return CoderResult.UNDERFLOW;

                    }

                    int b1 = (sa[sp] & 0xff) | 0x80;

                    int b2 = (sa[sp + 1] & 0xff) | 0x80;

                    char[] cc = toUnicode(b1, b2, plane);

                    // plane3 has non-bmp characters(added), x11cnsp3

                    // however does not support them

                    if (cc == null || cc.length == 2)

                        return CoderResult.unmappableForLength(2);

                    if (dl - dp < 1)

                        return CoderResult.OVERFLOW;

                    da[dp++] = cc[0];

                    sp +=2;

                }

                return CoderResult.UNDERFLOW;

            } finally {

                src.position(sp - src.arrayOffset());

                dst.position(dp - dst.arrayOffset());

            }

        }

    }

}