/*

 * Copyright (c) 2000, 2017, 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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 */

package sun.nio.cs;

import java.nio.ByteBuffer;

import java.nio.CharBuffer;

import java.nio.charset.Charset;

import java.nio.charset.CharsetDecoder;

import java.nio.charset.CharsetEncoder;

import java.nio.charset.CoderResult;

import java.util.Objects;

import jdk.internal.HotSpotIntrinsicCandidate;

public class ISO_8859_1

    extends Charset

    implements HistoricallyNamedCharset

{

    public ISO_8859_1() {

        super("ISO-8859-1", StandardCharsets.aliases_ISO_8859_1());

    }

    public String historicalName() {

        return "ISO8859_1";

    }

    public boolean contains(Charset cs) {

        return ((cs instanceof US_ASCII)

                || (cs instanceof ISO_8859_1));

    }

    public CharsetDecoder newDecoder() {

        return new Decoder(this);

    }

    public CharsetEncoder newEncoder() {

        return new Encoder(this);

    }

    private static class Decoder extends CharsetDecoder {

        private Decoder(Charset cs) {

            super(cs, 1.0f, 1.0f);

        }

        private CoderResult decodeArrayLoop(ByteBuffer src,

                                            CharBuffer dst)

        {

            byte[] sa = src.array();

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

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

            assert (sp <= sl);

            sp = (sp <= sl ? sp : sl);

            char[] da = dst.array();

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

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

            assert (dp <= dl);

            dp = (dp <= dl ? dp : dl);

            try {

                while (sp < sl) {

                    byte b = sa[sp];

                    if (dp >= dl)

                        return CoderResult.OVERFLOW;

                    da[dp++] = (char)(b & 0xff);

                    sp++;

                }

                return CoderResult.UNDERFLOW;

            } finally {

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

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

            }

        }

        private CoderResult decodeBufferLoop(ByteBuffer src,

                                             CharBuffer dst)

        {

            int mark = src.position();

            try {

                while (src.hasRemaining()) {

                    byte b = src.get();

                    if (!dst.hasRemaining())

                        return CoderResult.OVERFLOW;

                    dst.put((char)(b & 0xff));

                    mark++;

                }

                return CoderResult.UNDERFLOW;

            } finally {

                src.position(mark);

            }

        }

        protected CoderResult decodeLoop(ByteBuffer src,

                                         CharBuffer dst)

        {

            if (src.hasArray() && dst.hasArray())

                return decodeArrayLoop(src, dst);

            else

                return decodeBufferLoop(src, dst);

        }

    }

    private static class Encoder extends CharsetEncoder {

        private Encoder(Charset cs) {

            super(cs, 1.0f, 1.0f);

        }

        public boolean canEncode(char c) {

            return c <= '\u00FF';

        }

        public boolean isLegalReplacement(byte[] repl) {

            return true;  // we accept any byte value

        }

        private final Surrogate.Parser sgp = new Surrogate.Parser();

        // Method possible replaced with a compiler intrinsic.

        private static int encodeISOArray(char[] sa, int sp,

                                          byte[] da, int dp, int len) {

            if (len <= 0) {

                return 0;

            }

            encodeISOArrayCheck(sa, sp, da, dp, len);

            return implEncodeISOArray(sa, sp, da, dp, len);

        }

        @HotSpotIntrinsicCandidate

        private static int implEncodeISOArray(char[] sa, int sp,

                                              byte[] da, int dp, int len)

        {

            int i = 0;

            for (; i < len; i++) {

                char c = sa[sp++];

                if (c > '\u00FF')

                    break;

                da[dp++] = (byte)c;

            }

            return i;

        }

        private static void encodeISOArrayCheck(char[] sa, int sp,

                                                byte[] da, int dp, int len) {

            Objects.requireNonNull(sa);

            Objects.requireNonNull(da);

            if (sp < 0 || sp >= sa.length) {

                throw new ArrayIndexOutOfBoundsException(sp);

            }

            if (dp < 0 || dp >= da.length) {

                throw new ArrayIndexOutOfBoundsException(dp);

            }

            int endIndexSP = sp + len - 1;

            if (endIndexSP < 0 || endIndexSP >= sa.length) {

                throw new ArrayIndexOutOfBoundsException(endIndexSP);

            }

            int endIndexDP = dp + len - 1;

            if (endIndexDP < 0 || endIndexDP >= da.length) {

                throw new ArrayIndexOutOfBoundsException(endIndexDP);

            }

        }

        private CoderResult encodeArrayLoop(CharBuffer src,

                                            ByteBuffer dst)

        {

            char[] sa = src.array();

            int soff = src.arrayOffset();

            int sp = soff + src.position();

            int sl = soff + src.limit();

            assert (sp <= sl);

            sp = (sp <= sl ? sp : sl);

            byte[] da = dst.array();

            int doff = dst.arrayOffset();

            int dp = doff + dst.position();

            int dl = doff + dst.limit();

            assert (dp <= dl);

            dp = (dp <= dl ? dp : dl);

            int dlen = dl - dp;

            int slen = sl - sp;

            int len  = (dlen < slen) ? dlen : slen;

            try {

                int ret = encodeISOArray(sa, sp, da, dp, len);

                sp = sp + ret;

                dp = dp + ret;

                if (ret != len) {

                    if (sgp.parse(sa[sp], sa, sp, sl) < 0)

                        return sgp.error();

                    return sgp.unmappableResult();

                }

                if (len < slen)

                    return CoderResult.OVERFLOW;

                return CoderResult.UNDERFLOW;

            } finally {

                src.position(sp - soff);

                dst.position(dp - doff);

            }

        }

        private CoderResult encodeBufferLoop(CharBuffer src,

                                             ByteBuffer dst)

        {

            int mark = src.position();

            try {

                while (src.hasRemaining()) {

                    char c = src.get();

                    if (c <= '\u00FF') {

                        if (!dst.hasRemaining())

                            return CoderResult.OVERFLOW;

                        dst.put((byte)c);

                        mark++;

                        continue;

                    }

                    if (sgp.parse(c, src) < 0)

                        return sgp.error();

                    return sgp.unmappableResult();

                }

                return CoderResult.UNDERFLOW;

            } finally {

                src.position(mark);

            }

        }

        protected CoderResult encodeLoop(CharBuffer src,

                                         ByteBuffer dst)

        {

            if (src.hasArray() && dst.hasArray())

                return encodeArrayLoop(src, dst);

            else

                return encodeBufferLoop(src, dst);

        }

    }

}