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 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
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 * Copyright 2007-2010 Sun Microsystems, Inc. All rights reserved.
 *
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 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
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 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 * Sun designates this particular file as subject to the "Classpath" exception
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 * Header, with the fields enclosed by brackets [] replaced by your own
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package com.sun.grizzly.lzma.compression.rangecoder;

import java.io.IOException;

/**
 * Encoder
 *
 * @author Igor Pavlov
 */
public class Encoder {

    static final int kTopMask = ~((1 << 24) - 1);
    static final int kNumBitModelTotalBits = 11;
    static final int kBitModelTotal = (1 << kNumBitModelTotalBits);
    static final int kNumMoveBits = 5;
    java.io.OutputStream Stream;
    long Low;
    int Range;
    int _cacheSize;
    int _cache;
    long _position;

    public void SetStream(java.io.OutputStream stream) {
        Stream = stream;
    }

    public void ReleaseStream() {
        Stream = null;
    }

    public void Init() {
        _position = 0;
        Low = 0;
        Range = -1;
        _cacheSize = 1;
        _cache = 0;
    }

    public void FlushData() throws IOException {
        for (int i = 0; i < 5; i++) {
            ShiftLow();
        }
    }

    public void FlushStream() throws IOException {
        Stream.flush();
    }

    public void ShiftLow() throws IOException {
        int LowHi = (int) (Low >>> 32);
        if (LowHi != 0 || Low < 0xFF000000L) {
            _position += _cacheSize;
            int temp = _cache;
            do {
                Stream.write(temp + LowHi);
                temp = 0xFF;
            } while (--_cacheSize != 0);
            _cache = (((int) Low) >>> 24);
        }
        _cacheSize++;
        Low = (Low & 0xFFFFFF) << 8;
    }

    public void EncodeDirectBits(int v, int numTotalBits) throws IOException {
        for (int i = numTotalBits - 1; i >= 0; i--) {
            Range >>>= 1;
            if (((v >>> i) & 1) == 1) {
                Low += Range;
            }
            if ((Range & Encoder.kTopMask) == 0) {
                Range <<= 8;
                ShiftLow();
            }
        }
    }

    public long GetProcessedSizeAdd() {
        return _cacheSize + _position + 4;
    }
    static final int kNumMoveReducingBits = 2;
    public static final int kNumBitPriceShiftBits = 6;

    public static void InitBitModels(short[] probs) {
        for (int i = 0; i < probs.length; i++) {
            probs[i] = (kBitModelTotal >>> 1);
        }
    }

    public void Encode(short[] probs, int index, int symbol) throws IOException {
        int prob = probs[index];
        int newBound = (Range >>> kNumBitModelTotalBits) * prob;
        if (symbol == 0) {
            Range = newBound;
            probs[index] = (short) (prob + ((kBitModelTotal - prob) >>> kNumMoveBits));
        } else {
            Low += (newBound & 0xFFFFFFFFL);
            Range -= newBound;
            probs[index] = (short) (prob - ((prob) >>> kNumMoveBits));
        }
        if ((Range & kTopMask) == 0) {
            Range <<= 8;
            ShiftLow();
        }
    }
    private static int[] ProbPrices = new int[kBitModelTotal >>> kNumMoveReducingBits];

    static {
        int kNumBits = (kNumBitModelTotalBits - kNumMoveReducingBits);
        for (int i = kNumBits - 1; i >= 0; i--) {
            int start = 1 << (kNumBits - i - 1);
            int end = 1 << (kNumBits - i);
            for (int j = start; j < end; j++) {
                ProbPrices[j] = (i << kNumBitPriceShiftBits) +
                        (((end - j) << kNumBitPriceShiftBits) >>> (kNumBits - i - 1));
            }
        }
    }

    static public int GetPrice(int Prob, int symbol) {
        return ProbPrices[(((Prob - symbol) ^ ((-symbol))) & (kBitModelTotal - 1)) >>> kNumMoveReducingBits];
    }

    static public int GetPrice0(int Prob) {
        return ProbPrices[Prob >>> kNumMoveReducingBits];
    }

    static public int GetPrice1(int Prob) {
        return ProbPrices[(kBitModelTotal - Prob) >>> kNumMoveReducingBits];
    }
}