/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

package com.cherry.lib.doc.office.thirdpart.mozilla.intl.chardet;

import java.lang.*;

public abstract class nsPSMDetector
{

    public static final int ALL = 0;
    public static final int JAPANESE = 1;
    public static final int CHINESE = 2;
    public static final int SIMPLIFIED_CHINESE = 3;
    public static final int TRADITIONAL_CHINESE = 4;
    public static final int KOREAN = 5;

    public static final int NO_OF_LANGUAGES = 6;
    public static final int MAX_VERIFIERS = 16;

    nsVerifier[] mVerifier;
    nsEUCStatistics[] mStatisticsData;

    nsEUCSampler mSampler = new nsEUCSampler();
    byte[] mState = new byte[MAX_VERIFIERS];
    int[] mItemIdx = new int[MAX_VERIFIERS];

    int mItems;
    int mClassItems;

    boolean mDone;
    boolean mRunSampler;
    boolean mClassRunSampler;

    public nsPSMDetector()
    {
        initVerifiers(nsPSMDetector.ALL);
        Reset();
    }

    public nsPSMDetector(int langFlag)
    {
        initVerifiers(langFlag);
        Reset();
    }

    public nsPSMDetector(int aItems, nsVerifier[] aVerifierSet, nsEUCStatistics[] aStatisticsSet)
    {
        mClassRunSampler = (aStatisticsSet != null);
        mStatisticsData = aStatisticsSet;
        mVerifier = aVerifierSet;

        mClassItems = aItems;
        Reset();
    }

    public void Reset()
    {
        mRunSampler = mClassRunSampler;
        mDone = false;
        mItems = mClassItems;

        for (int i = 0; i < mItems; i++)
        {
            mState[i] = 0;
            mItemIdx[i] = i;
        }

        mSampler.Reset();
    }

    protected void initVerifiers(int currVerSet)
    {

        int idx = 0;
        int currVerifierSet;

        if (currVerSet >= 0 && currVerSet < NO_OF_LANGUAGES)
        {
            currVerifierSet = currVerSet;
        }
        else
        {
            currVerifierSet = nsPSMDetector.ALL;
        }

        mVerifier = null;
        mStatisticsData = null;

        if (currVerifierSet == nsPSMDetector.TRADITIONAL_CHINESE)
        {

            mVerifier = new nsVerifier[]{new nsUTF8Verifier(), new nsBIG5Verifier(),
                new nsISO2022CNVerifier(), new nsEUCTWVerifier(), new nsCP1252Verifier(),
                new nsUCS2BEVerifier(), new nsUCS2LEVerifier()};

            mStatisticsData = new nsEUCStatistics[]{null, new Big5Statistics(), null,
                new EUCTWStatistics(), null, null, null};
        }

        //==========================================================
        else if (currVerifierSet == nsPSMDetector.KOREAN)
        {

            mVerifier = new nsVerifier[]{new nsUTF8Verifier(), new nsEUCKRVerifier(),
                new nsISO2022KRVerifier(), new nsCP1252Verifier(), new nsUCS2BEVerifier(),
                new nsUCS2LEVerifier()};
        }

        //==========================================================
        else if (currVerifierSet == nsPSMDetector.SIMPLIFIED_CHINESE)
        {

            mVerifier = new nsVerifier[]{new nsUTF8Verifier(), new nsGB2312Verifier(),
                new nsGB18030Verifier(), new nsISO2022CNVerifier(), new nsHZVerifier(),
                new nsCP1252Verifier(), new nsUCS2BEVerifier(), new nsUCS2LEVerifier()};
        }

        //==========================================================
        else if (currVerifierSet == nsPSMDetector.JAPANESE)
        {
            mVerifier = new nsVerifier[]{new nsUTF8Verifier(), new nsSJISVerifier(),
                new nsEUCJPVerifier(), new nsISO2022JPVerifier(), new nsCP1252Verifier(),
                new nsUCS2BEVerifier(), new nsUCS2LEVerifier()};
        }
        //==========================================================
        else if (currVerifierSet == nsPSMDetector.CHINESE)
        {

            mVerifier = new nsVerifier[]{new nsUTF8Verifier(), new nsGB2312Verifier(),
                new nsGB18030Verifier(), new nsBIG5Verifier(), new nsISO2022CNVerifier(),
                new nsHZVerifier(), new nsEUCTWVerifier(), new nsCP1252Verifier(),
                new nsUCS2BEVerifier(), new nsUCS2LEVerifier()};

            mStatisticsData = new nsEUCStatistics[]{null, new GB2312Statistics(), null,
                new Big5Statistics(), null, null, new EUCTWStatistics(), null, null, null};
        }

        //==========================================================
        else if (currVerifierSet == nsPSMDetector.ALL)
        {

            mVerifier = new nsVerifier[]{new nsUTF8Verifier(), new nsSJISVerifier(),
                new nsEUCJPVerifier(), new nsISO2022JPVerifier(), new nsEUCKRVerifier(),
                new nsISO2022KRVerifier(), new nsBIG5Verifier(), new nsEUCTWVerifier(),
                new nsGB2312Verifier(), new nsGB18030Verifier(), new nsISO2022CNVerifier(),
                new nsHZVerifier(), new nsCP1252Verifier(), new nsUCS2BEVerifier(),
                new nsUCS2LEVerifier()};

            mStatisticsData = new nsEUCStatistics[]{null, null, new EUCJPStatistics(), null,
                new EUCKRStatistics(), null, new Big5Statistics(), new EUCTWStatistics(),
                new GB2312Statistics(), null, null, null, null, null, null};
        }

        mClassRunSampler = (mStatisticsData != null);
        mClassItems = mVerifier.length;

    }

    public abstract void Report(String charset);

    public boolean HandleData(byte[] aBuf, int len)
    {

        int i, j;
        byte b, st;

        for (i = 0; i < len; i++)
        {
            b = aBuf[i];
            for (j = 0; j < mItems;)
            {
                st = nsVerifier.getNextState(mVerifier[mItemIdx[j]], b, mState[j]);
                if (st == nsVerifier.eItsMe)
                {
                    Report(mVerifier[mItemIdx[j]].charset());
                    mDone = true;
                    return mDone;
                }
                else if (st == nsVerifier.eError)
                {
                    mItems--;
                    if (j < mItems)
                    {
                        mItemIdx[j] = mItemIdx[mItems];
                        mState[j] = mState[mItems];
                    }
                }
                else
                {
                    mState[j++] = st;
                }
            }
            if (mItems <= 1)
            {
                if (1 == mItems)
                {
                    Report(mVerifier[mItemIdx[0]].charset());
                }
                mDone = true;
                return mDone;
            }
            else
            {
                int nonUCS2Num = 0;
                int nonUCS2Idx = 0;
                for (j = 0; j < mItems; j++)
                {
                    if ((!(mVerifier[mItemIdx[j]].isUCS2()))
                        && (!(mVerifier[mItemIdx[j]].isUCS2())))
                    {
                        nonUCS2Num++;
                        nonUCS2Idx = j;
                    }
                }
                if (1 == nonUCS2Num)
                {
                    Report(mVerifier[mItemIdx[nonUCS2Idx]].charset());
                    mDone = true;
                    return mDone;
                }
            }
        }
        if (mRunSampler)
        {
            Sample(aBuf, len);
        }
        return mDone;
    }

    public void DataEnd()
    {
        if (mDone == true)
        {
            return;
        }

        if (mItems == 2)
        {
            if ((mVerifier[mItemIdx[0]].charset()).equals("GB18030"))
            {
                Report(mVerifier[mItemIdx[1]].charset());
                mDone = true;
            }
            else if ((mVerifier[mItemIdx[1]].charset()).equals("GB18030"))
            {
                Report(mVerifier[mItemIdx[0]].charset());
                mDone = true;
            }
        }
        if (mItems == 4)
        {
            if ((mVerifier[mItemIdx[1]].charset()).equals("Shift_JIS"))
            {
                Report(mVerifier[mItemIdx[1]].charset());
                mDone = true;
            }
        }
        if (mRunSampler)
        {
            Sample(null, 0, true);
        }
    }

    public void Sample(byte[] aBuf, int aLen)
    {
        Sample(aBuf, aLen, false);
    }

    public void Sample(byte[] aBuf, int aLen, boolean aLastChance)
    {
        int possibleCandidateNum = 0;
        int j;
        int eucNum = 0;

        for (j = 0; j < mItems; j++)
        {
            if (null != mStatisticsData[mItemIdx[j]])
                eucNum++;
            if ((!mVerifier[mItemIdx[j]].isUCS2())
                && (!(mVerifier[mItemIdx[j]].charset()).equals("GB18030")))
                possibleCandidateNum++;
        }

        mRunSampler = (eucNum > 1);

        if (mRunSampler)
        {
            mRunSampler = mSampler.Sample(aBuf, aLen);
            if (((aLastChance && mSampler.GetSomeData()) || mSampler.EnoughData())
                && (eucNum == possibleCandidateNum))
            {
                mSampler.CalFreq();

                int bestIdx = -1;
                int eucCnt = 0;
                float bestScore = 0.0f;
                for (j = 0; j < mItems; j++)
                {
                    if ((null != mStatisticsData[mItemIdx[j]])
                        && (!(mVerifier[mItemIdx[j]].charset()).equals("Big5")))
                    {
                        float score = mSampler.GetScore(
                            mStatisticsData[mItemIdx[j]].mFirstByteFreq(),
                            mStatisticsData[mItemIdx[j]].mFirstByteWeight(),
                            mStatisticsData[mItemIdx[j]].mSecondByteFreq(),
                            mStatisticsData[mItemIdx[j]].mSecondByteWeight());
                        //System.out.println("FequencyScore("+mVerifier[mItemIdx[j]].charset()+")= "+ score);
                        if ((0 == eucCnt++) || (bestScore > score))
                        {
                            bestScore = score;
                            bestIdx = j;
                        } // if(( 0 == eucCnt++) || (bestScore > score )) 
                    } // if(null != ...)
                } // for
                if (bestIdx >= 0)
                {
                    Report(mVerifier[mItemIdx[bestIdx]].charset());
                    mDone = true;
                }
            } // if (eucNum == possibleCandidateNum)
        } // if(mRunSampler)
    }

    public String[] getProbableCharsets()
    {
        if (mItems <= 0)
        {
            String[] nomatch = new String[1];
            nomatch[0] = "nomatch";
            return nomatch;
        }
        String ret[] = new String[mItems];
        for (int i = 0; i < mItems; i++)
        {
            ret[i] = mVerifier[mItemIdx[i]].charset();
        }
        return ret;
    }

}
