sl@0: // Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: //
sl@0: 
sl@0: #include <apmrec.h>
sl@0: #include <apmstd.h>
sl@0: #include "RECTXT.H"
sl@0: #include <ecom/implementationproxy.h>
sl@0: 
sl@0: const TUid KUidMimeTxtRecognizer={0x100012FB};
sl@0: const TInt KMinBufferLength=42;  // minimum amount of file needed to determine a text file IF it's not called .TXT
sl@0: const TInt KMaxBufferLength=1024; // maximum amount of buffer space we will ever use
sl@0: _LIT8(KDataTypeTextPlain,"text/plain");
sl@0: _LIT(KTextFileExt,".txt");
sl@0: 
sl@0: CApaTextRecognizer::CApaTextRecognizer()
sl@0: 	:CApaDataRecognizerType(KUidMimeTxtRecognizer,CApaDataRecognizerType::ELow)
sl@0: 	// Text files are low recognition - they don't have a clear signature
sl@0: 	{
sl@0: 	iCountDataTypes=1;
sl@0: 	}
sl@0: 
sl@0: TUint CApaTextRecognizer::PreferredBufSize()
sl@0: 	{
sl@0: 	return KMaxBufferLength;
sl@0: 	}
sl@0: 
sl@0: #if defined(_DEBUG)
sl@0: TDataType CApaTextRecognizer::SupportedDataTypeL(TInt aIndex) const
sl@0: #else
sl@0: TDataType CApaTextRecognizer::SupportedDataTypeL(TInt /*aIndex*/) const
sl@0: #endif
sl@0: 	{
sl@0: 	__ASSERT_DEBUG(aIndex==0,User::Invariant());
sl@0: 	return TDataType(KDataTypeTextPlain);
sl@0: 	}
sl@0: 
sl@0: void CApaTextRecognizer::DoRecognizeL(const TDesC& aName, const TDesC8& aBuffer)
sl@0: 	{
sl@0: 	TBool nameRecognized=EFalse;
sl@0:     
sl@0: 	// check if the file has valid UIDs 
sl@0: 	if (aBuffer.Length() >= 16)
sl@0: 		{
sl@0: 		// if the first 3 bytes are valid UIDs,then this file is not a plain/text. 
sl@0: 		// Set iConfidence appropriately and exit.
sl@0: 		const TCheckedUid checkUid(aBuffer.Left(16));    
sl@0: 		if (checkUid.UidType().IsValid())
sl@0: 			{
sl@0: 			iConfidence=ENotRecognized;
sl@0: 			return;
sl@0: 			}
sl@0: 		}
sl@0: 
sl@0: 	if (aName.Length()>4)
sl@0: 		{
sl@0: 		nameRecognized=(aName.Right(4).CompareF(KTextFileExt)==0);
sl@0: 		}
sl@0: 	const TInt length=Min(aBuffer.Length(), KMaxBufferLength);
sl@0: 	if (length<KMinBufferLength && !nameRecognized)
sl@0: 		return;
sl@0: 	TInt ii;
sl@0: 	for (ii=0; ii<length; ii++)
sl@0: 		{
sl@0: 		const TUint chr=aBuffer[ii];
sl@0: 		// these are guesses of what WON'T be in a text file
sl@0: 		if (chr<9 || chr==11 || chr==12 || (chr>13 && chr<32))
sl@0: 			{
sl@0: 			break;
sl@0: 			}
sl@0: 		if (chr>148)
sl@0: 			{
sl@0: 			break;
sl@0: 			}
sl@0: 		}
sl@0: 	const TBool validChars=(ii==length);
sl@0: 	
sl@0: 	if (nameRecognized)
sl@0: 		{
sl@0: 		iConfidence=validChars? EProbable : EUnlikely;
sl@0: 		}
sl@0: 	else
sl@0: 		{
sl@0: 		if (!validChars)
sl@0: 			{
sl@0: 			return;
sl@0: 			}
sl@0: 		iConfidence=EPossible;
sl@0: 		}
sl@0: 	iDataType=TDataType(KDataTypeTextPlain);
sl@0: 	}
sl@0: 
sl@0: CApaDataRecognizerType* CApaTextRecognizer::CreateRecognizerL()
sl@0: 	{
sl@0: 	return new (ELeave) CApaTextRecognizer();
sl@0: 	}
sl@0: 
sl@0: const TImplementationProxy ImplementationTable[] = 
sl@0:     {
sl@0: 	IMPLEMENTATION_PROXY_ENTRY(0x101F7DA0,CApaTextRecognizer::CreateRecognizerL)
sl@0: 	};
sl@0: 
sl@0: EXPORT_C const TImplementationProxy* ImplementationGroupProxy(TInt& aTableCount)
sl@0:     {
sl@0:     aTableCount = sizeof(ImplementationTable) / sizeof(TImplementationProxy);
sl@0:     return ImplementationTable;
sl@0:     }
sl@0: 
sl@0: