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/* ***** 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.
 *
 * Contributor(s):
 *   Kohei TAKETA  (Java port)
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either 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 org.mozilla.universalchardet.prober;

import org.mozilla.universalchardet.prober.statemachine.CodingStateMachine;
import org.mozilla.universalchardet.prober.statemachine.SJISSMModel;
import org.mozilla.universalchardet.prober.statemachine.SMModel;
import org.mozilla.universalchardet.prober.contextanalysis.SJISContextAnalysis;
import org.mozilla.universalchardet.prober.distributionanalysis.SJISDistributionAnalysis;
import org.mozilla.universalchardet.Constants;


public class SJISProber extends CharsetProber
{
    ////////////////////////////////////////////////////////////////
    // fields
    ////////////////////////////////////////////////////////////////
    private CodingStateMachine          codingSM;
    private ProbingState                state;
    
    private SJISContextAnalysis         contextAnalyzer;
    private SJISDistributionAnalysis    distributionAnalyzer;
    
    private byte[]                      lastChar;
    
    private static final SMModel smModel = new SJISSMModel();
    

    ////////////////////////////////////////////////////////////////
    // methods
    ////////////////////////////////////////////////////////////////
    public SJISProber()
    {
        super();
        this.codingSM = new CodingStateMachine(smModel);
        this.contextAnalyzer = new SJISContextAnalysis();
        this.distributionAnalyzer = new SJISDistributionAnalysis();
        this.lastChar = new byte[2];
        reset();
    }

    @Override
    public String getCharSetName()
    {
        return Constants.CHARSET_SHIFT_JIS;
    }

    @Override
    public float getConfidence()
    {
        float contextCf = this.contextAnalyzer.getConfidence();
        float distribCf = this.distributionAnalyzer.getConfidence();
        
        return Math.max(contextCf, distribCf);
    }

    @Override
    public ProbingState getState()
    {
        return this.state;
    }

    @Override
    public ProbingState handleData(byte[] buf, int offset, int length)
    {
        int codingState;
        
        int maxPos = offset + length;
        for (int i=offset; i SHORTCUT_THRESHOLD) {
                this.state = ProbingState.FOUND_IT;
            }
        }
        
        return this.state;
    }

    @Override
    public void reset()
    {
        this.codingSM.reset();
        this.state = ProbingState.DETECTING;
        this.contextAnalyzer.reset();
        this.distributionAnalyzer.reset();
        java.util.Arrays.fill(this.lastChar, (byte)0);
    }

    @Override
    public void setOption()
    {}
}