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 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 // for S-JIS encoding, observed characteristic:
 // 1, kana character (or hankaku?) often have hight frequency of appearance
 // 2, kana character often exist in group
 // 3, certain combination of kana is never used in japanese language
 
 #pragma GCC visibility push(hidden)
 
 #include "nsSJISProber.h"
 
 void  nsSJISProber::Reset(void)
 {
   mCodingSM->Reset(); 
   mState = eDetecting;
   mContextAnalyser.Reset();
   mDistributionAnalyser.Reset();
 }
 
 nsProbingState nsSJISProber::HandleData(const char* aBuf, PRUint32 aLen)
 {
   nsSMState codingState;
 
   for (PRUint32 i = 0; i < aLen; i++)
   {
     codingState = mCodingSM->NextState(aBuf[i]);
     if (codingState == eError)
     {
       mState = eNotMe;
       break;
     }
     if (codingState == eItsMe)
     {
       mState = eFoundIt;
       break;
     }
     if (codingState == eStart)
     {
       PRUint32 charLen = mCodingSM->GetCurrentCharLen();
       if (i == 0)
       {
         mLastChar[1] = aBuf[0];
         mContextAnalyser.HandleOneChar(mLastChar+2-charLen, charLen);
         mDistributionAnalyser.HandleOneChar(mLastChar, charLen);
       }
       else
       {
         mContextAnalyser.HandleOneChar(aBuf+i+1-charLen, charLen);
         mDistributionAnalyser.HandleOneChar(aBuf+i-1, charLen);
       }
     }
   }
 
   mLastChar[0] = aBuf[aLen-1];
 
   if (mState == eDetecting)
     if (mContextAnalyser.GotEnoughData() && GetConfidence() > SHORTCUT_THRESHOLD)
       mState = eFoundIt;
 
   return mState;
 }
 
 float nsSJISProber::GetConfidence(void)
 {
   float contxtCf = mContextAnalyser.GetConfidence();
   float distribCf = mDistributionAnalyser.GetConfidence();
 
   return (contxtCf > distribCf ? contxtCf : distribCf);
 }
 
 #pragma GCC visibility pop