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 /* -*- 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
  * 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 ***** */
 
 #pragma GCC visibility push(hidden)
 
 #include <stdio.h>
 #include "prmem.h"
 
 #include "nsMBCSGroupProber.h"
 
 #ifdef DEBUG_chardet
 char *ProberName[] = 
 {
   "UTF8",
   "SJIS",
   "EUCJP",
   "GB18030",
   "EUCKR",
   "Big5",
   "EUCTW",
 };
 
 #endif
 
 nsMBCSGroupProber::nsMBCSGroupProber()
 {
   mProbers[0] = new nsUTF8Prober();
   mProbers[1] = new nsSJISProber();
   mProbers[2] = new nsEUCJPProber();
   mProbers[3] = new nsGB18030Prober();
   mProbers[4] = new nsEUCKRProber();
   mProbers[5] = new nsBig5Prober();
   mProbers[6] = new nsEUCTWProber();
   Reset();
 }
 
 nsMBCSGroupProber::~nsMBCSGroupProber()
 {
   for (PRUint32 i = 0; i < NUM_OF_PROBERS; i++)
   {
     delete mProbers[i];
   }
 }
 
 const char* nsMBCSGroupProber::GetCharSetName()
 {
   if (mBestGuess == -1)
   {
     GetConfidence();
     if (mBestGuess == -1)
       mBestGuess = 0;
   }
   return mProbers[mBestGuess]->GetCharSetName();
 }
 
 void  nsMBCSGroupProber::Reset(void)
 {
   mActiveNum = 0;
   for (PRUint32 i = 0; i < NUM_OF_PROBERS; i++)
   {
     if (mProbers[i])
     {
       mProbers[i]->Reset();
       mIsActive[i] = PR_TRUE;
       ++mActiveNum;
     }
     else
       mIsActive[i] = PR_FALSE;
   }
   mBestGuess = -1;
   mState = eDetecting;
 }
 
 nsProbingState nsMBCSGroupProber::HandleData(const char* aBuf, PRUint32 aLen)
 {
   nsProbingState st;
   PRUint32 i;
 
   //do filtering to reduce load to probers
   char *highbyteBuf;
   char *hptr;
   PRBool keepNext = PR_TRUE;   //assume previous is not ascii, it will do no harm except add some noise
   hptr = highbyteBuf = (char*)PR_Malloc(aLen);
   if (!hptr)
       return mState;
   for (i = 0; i < aLen; i++)
   {
     if (aBuf[i] & 0x80)
     {
       *hptr++ = aBuf[i];
       keepNext = PR_TRUE;
     }
     else
     {
       //if previous is highbyte, keep this even it is a ASCII
       if (keepNext)
       {
           *hptr++ = aBuf[i];
           keepNext = PR_FALSE;
       }
     }
   }
 
   for (i = 0; i < NUM_OF_PROBERS; i++)
   {
      if (!mIsActive[i])
        continue;
      st = mProbers[i]->HandleData(highbyteBuf, hptr - highbyteBuf);
      if (st == eFoundIt)
      {
        mBestGuess = i;
        mState = eFoundIt;
        break;
      }
      else if (st == eNotMe)
      {
        mIsActive[i] = PR_FALSE;
        mActiveNum--;
        if (mActiveNum <= 0)
        {
          mState = eNotMe;
          break;
        }
      }
   }
 
   PR_FREEIF(highbyteBuf);
 
   return mState;
 }
 
 float nsMBCSGroupProber::GetConfidence(void)
 {
   PRUint32 i;
   float bestConf = 0.0, cf;
 
   switch (mState)
   {
   case eFoundIt:
     return (float)0.99;
   case eNotMe:
     return (float)0.01;
   default:
     for (i = 0; i < NUM_OF_PROBERS; i++)
     {
       if (!mIsActive[i])
         continue;
       cf = mProbers[i]->GetConfidence();
       if (bestConf < cf)
       {
         bestConf = cf;
         mBestGuess = i;
       }
     }
   }
   return bestConf;
 }
 
 #ifdef DEBUG_chardet
 void nsMBCSGroupProber::DumpStatus()
 {
   PRUint32 i;
   float cf;
   
   GetConfidence();
   for (i = 0; i < NUM_OF_PROBERS; i++)
   {
     if (!mIsActive[i])
       printf("  MBCS inactive: [%s] (confidence is too low).\r\n", ProberName[i]);
     else
     {
       cf = mProbers[i]->GetConfidence();
       printf("  MBCS %1.3f: [%s]\r\n", cf, ProberName[i]);
     }
   }
 }
 #endif
 
 #pragma GCC visibility pop