// Copyright (c) 2001-2009 Nokia Corporation and/or its subsidiary(-ies).

 // All rights reserved.

 // This component and the accompanying materials are made available

 // under the terms of "Eclipse Public License v1.0"

 // which accompanies this distribution, and is available

 // at the URL "http://www.eclipse.org/legal/epl-v10.html".

 //

 // Initial Contributors:

 // Nokia Corporation - initial contribution.

 //

 // Contributors:

 //

 // Description:

 //

 #if !defined(__E32STD_H__)

 #include <e32std.h>

 #endif

 #if !defined(__BADICTIONARYCOMPRESSION_H__)

 #define __BADICTIONARYCOMPRESSION_H__

 #include "BaAssert.h"

 /**

 This class implements a stream of bits (least significant bit first) as used by the code reading dictionary-compressed resource-files

 @internalComponent

 */

 class RDictionaryCompressionBitStream

 	{

 public:

 	RDictionaryCompressionBitStream();

 	void OpenL(

 		TInt aNumberOfBitsUsedForDictionaryTokens,

 		TInt aOffsetToFirstBit,

 		TInt aOffsetOnePastLastBit,

 		TBool aTransferringOwnershipOfBuffer,

 		TUint8* aBuffer,

 		const TBaAssert& aAssertObj);

 	void Close();

 	TBool EndOfStreamL() const;

 	TInt IndexOfDictionaryEntryL(); // increments the current bit-position if it returns a value >=0; returns a negative value if the next thing in the stream is plain data rather than the index of a dictionary entry

  	void ReadL(TDes8& aBufferToAppendTo,TBool aCalypsoFileFormat); // can only be called if IndexOfDictionaryEntry returned a negative value

 private:

 	TBool CurrentBitIsOn() const; // does not increment the current bit-position

 	TUint ReadIntegerL(TInt aNumberOfBits); // increments the current bit-position

 private:

 	TInt iNumberOfBitsUsedForDictionaryTokens;

 	TInt iOffsetToFirstBit;

 	TInt iOffsetToCurrentBit;

 	TInt iOffsetOnePastLastBit;

 	TBool iOwnsBitBuffer;

 	TUint8* iBuffer;

 	TBaAssert iAssertObj;

 	};

 #endif