public SingleByteCharSetProber(SequenceModel model, bool reversed, AbstractCSProber nameProber)
{
mModel = model;
mReversed = reversed;
mNameProber = nameProber;
Reset();
}
public UniversalDetector()
{
mDone = false;
mBestGuess = -1; //illegal value as signal
mInTag = false;
mEscCharSetProber = null;
mStart = true;
mDetectedCharset = null;
mGotData = false;
mInputState = InputState.PureAscii;
mLastChar = 0;
mCharSetProbers.Clear();
}
public virtual void DataEnd()
{
if (!mGotData)
{
// we haven't got any data yet, return immediately
// caller program sometimes call DataEnd before anything has been sent to detector
return;
}
if (mDetectedCharset != null)
{
mDone = true;
Report(mDetectedCharset);
return;
}
switch (mInputState)
{
case InputState.Highbyte:
{
AbstractCSProber maxProber = null;
foreach (AbstractCSProber prober in mCharSetProbers)
{
if (prober == null)
{
continue;
}
if (maxProber == null || (prober.GetConfidence() > maxProber.GetConfidence()))
{
maxProber = prober;
}
}
//do not report anything because we are not confident of it, that's in fact a negative answer
if (maxProber != null && (maxProber.GetConfidence() > MINIMUM_THRESHOLD))
{
Report(maxProber.CharSetName);
}
}
break;
case InputState.EscAscii:
break;
default:
break;
}
return;
}
public void SetModelProbers(AbstractCSProber logicalPrb, AbstractCSProber visualPrb)
{
mLogicalProb = logicalPrb;
mVisualProb = visualPrb;
}
public virtual int HandleData(byte[] aBuf)
{
if (mDone)
{
return(NS_OK);
}
if (aBuf.Length > 0)
{
mGotData = true;
}
//If the data starts with BOM, we know it is UTF
if (mStart)
{
mStart = false;
if (aBuf.Length > 3)
{
switch (aBuf[0])
{
case 0xEF:
if ((0xBB == aBuf[1]) && (0xBF == aBuf[2]))
{
// EF BB BF UTF-8 encoded BOM
mDetectedCharset = "UTF-8";
}
break;
case 0xFE:
if ((0xFF == aBuf[1]) && (0x00 == aBuf[2]) && (0x00 == aBuf[3]))
{
// FE FF 00 00 UCS-4, unusual octet order BOM (3412)
mDetectedCharset = "X-ISO-10646-UCS-4-3412";
}
else if (0xFF == aBuf[1])
{
// FE FF UTF-16, big endian BOM
mDetectedCharset = "UTF-16BE";
}
break;
case 0x00:
if ((0x00 == aBuf[1]) && (0xFE == aBuf[2]) && (0xFF == aBuf[3]))
{
// 00 00 FE FF UTF-32, big-endian BOM
mDetectedCharset = "UTF-32BE";
}
else if ((0x00 == aBuf[1]) && (0xFF == aBuf[2]) && (0xFE == aBuf[3]))
{
// 00 00 FF FE UCS-4, unusual octet order BOM (2143)
mDetectedCharset = "X-ISO-10646-UCS-4-2143";
}
break;
case 0xFF:
if ((0xFE == aBuf[1]) && (0x00 == aBuf[2]) && (0x00 == aBuf[3]))
{
// FF FE 00 00 UTF-32, little-endian BOM
mDetectedCharset = "UTF-32LE";
}
else if (0xFE == aBuf[1])
{
// FF FE UTF-16, little endian BOM
mDetectedCharset = "UTF-16LE";
}
break;
} // switch
}
if (mDetectedCharset != null)
{
mDone = true;
return(NS_OK);
}
}
for (int i = 0; i < aBuf.Length; i++)
{
//other than 0xa0, if every othe character is ascii, the page is ascii
if ((aBuf[i] & 0x80) > 0 && aBuf[i] != 0xA0) //Since many Ascii only page contains NBSP
{
//we got a non-ascii byte (high-byte)
if (mInputState != InputState.Highbyte)
{
//adjust state
mInputState = InputState.Highbyte;
//kill mEscCharSetProber if it is active
if (mEscCharSetProber != null)
{
mEscCharSetProber = null;
}
//TODO: take out when implement nsMBCSGroupProber
mCharSetProbers.Add(new UTF8Prober());
//start multibyte and singlebyte charset prober
//mCharSetProbers.Add(new nsMBCSGroupProber());
mCharSetProbers.Add(new SBCSGroupProber());
mCharSetProbers.Add(new Latin1Prober());
}
}
else
{
//ok, just pure ascii so far
if (InputState.PureAscii == mInputState &&
(aBuf[i] == 33 || (aBuf[i] == '{' && mLastChar == '~')))
{
//found escape character or HZ "~{"
mInputState = InputState.EscAscii;
}
mLastChar = aBuf[i];
}
}
ProbingState st;
switch (mInputState)
{
case InputState.EscAscii:
/*
* if (mEscCharSetProber == null) {
* mEscCharSetProber = new nsEscCharSetProber();
* }
*
* st = mEscCharSetProber.HandleData(aBuf, aLen);
* if (st == eFoundIt)
* {
* mDone = PR_TRUE;
* mDetectedCharset = mEscCharSetProber.GetCharSetName();
* }
*/
break;
case InputState.Highbyte:
foreach (AbstractCSProber prober in mCharSetProbers)
{
if (!prober.IsActive)
{
continue;
}
st = prober.HandleData(aBuf);
if (st == ProbingState.FoundIt)
{
mDone = true;
mDetectedCharset = prober.CharSetName;
return(NS_OK);
}
}
break;
default: //pure ascii
break; //do nothing here
}
return(NS_OK);
}