/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* ***** 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 Universal charset detector code.

 *

 * The Initial Developer of the Original Code is

 * Netscape Communications Corporation.

 * Portions created by the Initial Developer are Copyright (C) 2001

 * the Initial Developer. All Rights Reserved.

 *

 * Contributor(s):

 *          Shy Shalom <shooshX@gmail.com>

 *

 * 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

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 * decision by deleting the provisions above and replace them with the notice

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 * the provisions above, a recipient may use your version of this file under

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 * ***** END LICENSE BLOCK ***** */

#ifndef nsSingleByteCharSetProber_h__

#define nsSingleByteCharSetProber_h__

#include "nsCharSetProber.h"

#define SAMPLE_SIZE 64

#define SB_ENOUGH_REL_THRESHOLD  1024

#define POSITIVE_SHORTCUT_THRESHOLD  (float)0.95

#define NEGATIVE_SHORTCUT_THRESHOLD  (float)0.05

#define SYMBOL_CAT_ORDER  250

#define NUMBER_OF_SEQ_CAT 4

#define POSITIVE_CAT   (NUMBER_OF_SEQ_CAT-1)

#define NEGATIVE_CAT   0

typedef struct

{

  const unsigned char* const charToOrderMap;    // [256] table use to find a char's order

  const char* const precedenceMatrix;           // [SAMPLE_SIZE][SAMPLE_SIZE]; table to find a 2-char sequence's frequency

  float  mTypicalPositiveRatio;     // = freqSeqs / totalSeqs 

  PRBool keepEnglishLetter;         // says if this script contains English characters (not implemented)

  const char* const charsetName;

} SequenceModel;

class nsSingleByteCharSetProber : public nsCharSetProber{

public:

  nsSingleByteCharSetProber(const SequenceModel *model) 

    :mModel(model), mReversed(PR_FALSE), mNameProber(0) { Reset(); }

  nsSingleByteCharSetProber(const SequenceModel *model, PRBool reversed, nsCharSetProber* nameProber)

    :mModel(model), mReversed(reversed), mNameProber(nameProber) { Reset(); }

  virtual const char* GetCharSetName();

  virtual nsProbingState HandleData(const char* aBuf, PRUint32 aLen);

  virtual nsProbingState GetState(void) {return mState;}

  virtual void      Reset(void);

  virtual float     GetConfidence(void);

  virtual void      SetOpion() {}

  // This feature is not implemented yet. any current language model

  // contain this parameter as PR_FALSE. No one is looking at this

  // parameter or calling this method.

  // Moreover, the nsSBCSGroupProber which calls the HandleData of this

  // prober has a hard-coded call to FilterWithoutEnglishLetters which gets rid

  // of the English letters.

  PRBool KeepEnglishLetters() {return mModel->keepEnglishLetter;} // (not implemented)

#ifdef DEBUG_chardet

  virtual void  DumpStatus();

#endif

protected:

  nsProbingState mState;

  const SequenceModel* const mModel;

  const PRBool mReversed; // PR_TRUE if we need to reverse every pair in the model lookup

  //char order of last character

  unsigned char mLastOrder;

  PRUint32 mTotalSeqs;

  PRUint32 mSeqCounters[NUMBER_OF_SEQ_CAT];

  PRUint32 mTotalChar;

  //characters that fall in our sampling range

  PRUint32 mFreqChar;

  // Optional auxiliary prober for name decision. created and destroyed by the GroupProber

  nsCharSetProber* mNameProber; 

};

extern const SequenceModel Koi8rModel;

extern const SequenceModel Win1251Model;

extern const SequenceModel Latin5Model;

extern const SequenceModel MacCyrillicModel;

extern const SequenceModel Ibm866Model;

extern const SequenceModel Ibm855Model;

extern const SequenceModel Latin7Model;

extern const SequenceModel Win1253Model;

extern const SequenceModel Latin5BulgarianModel;

extern const SequenceModel Win1251BulgarianModel;

extern const SequenceModel Latin2HungarianModel;

extern const SequenceModel Win1250HungarianModel;

extern const SequenceModel Win1255Model;

extern const SequenceModel TIS620ThaiModel;

#endif /* nsSingleByteCharSetProber_h__ */