// Copyright (c) 2003-2009 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:

//

#ifndef __GZIP_H__

#define __GZIP_H__

#include <ezdecompressor.h>

#include <ezcompressor.h>

#include <ezfilebuffer.h>

/**

The TEZGZipHeader class encapsulates a zip file header, which is written to the start of the zip

file to store various settings of the archive

@publishedAll

@released

*/

class TEZGZipHeader

	{

public:

	IMPORT_C TEZGZipHeader();

	IMPORT_C ~TEZGZipHeader();

public:

	TUint8 iId1;

	TUint8 iId2;

	TUint8 iCompressionMethod;

	TUint8 iFlags;

	TInt32 iTime;

	TUint8 iExtraFlags;

	TUint8 iOs;

	TInt16 iXlen;

	HBufC8* iExtra;

	HBufC8* iFname;

	HBufC8* iComment;

	TInt16 iCrc;

	};

/**

The TEZGZipTrailer class encapsulates a zip file trailer, which uses a CRC (cyclic redundancy check) to 

confirm the validity of the unpacked archive

@publishedAll

@released

*/

class TEZGZipTrailer

	{

public:

	IMPORT_C TEZGZipTrailer();

	IMPORT_C TEZGZipTrailer(TInt32 aCrc, TInt32 aSize);

public:

	TInt32 iCrc32;

	TInt32 iSize;

	};

/**

The EZGZipFile class handles writing / reading of headers and trailers to / from zip files

@publishedAll

@released

*/

class EZGZipFile

	{

public:

	/** Zip file error codes */	

	enum { 	ENotGZipFile = KEZlibErrNotGZipFile, 					

			EInvalidCompressionMethod = KEZlibErrInvalidCompression,

			EBadGZipHeader= KEZlibErrBadGZipHeader, 				

			EBadGZipTrailer = KEZlibErrBadGZipTrailer, 				

			EBadGZipCrc = KEZlibErrBadGZipCrc };					

	/** Flags to determine which part of the header / trailer is being written */			

	enum { EFText = 0, EFHcrc = 1, EFExtra = 2, EFName = 3, EFComment = 4};

public:

	IMPORT_C static void ReadHeaderL(RFile &aFile, TEZGZipHeader &aHeader);

	IMPORT_C static void WriteHeaderL(RFile &aFile, TEZGZipHeader &aHeader);

	IMPORT_C static void ReadTrailerL(RFile &aFile, TEZGZipTrailer &aTrailer);

	IMPORT_C static void WriteTrailerL(RFile &aFile, TEZGZipTrailer &aTrailer);

	IMPORT_C static void LocateAndReadTrailerL(RFs &aRfs, const TDesC &aFname, TEZGZipTrailer &aTrailer);

	IMPORT_C static TBool IsGzipFile(RFs &aRfs, const TDesC &aFname);

	IMPORT_C static TBool IsGzipFileL(RFs &aRfs, const TDesC &aFname);

private:

	static void ReadStringIntoDescriptorL(RFile &aFile, HBufC8 **aDes);

public:

	/** First of the header ID pair */

	static const TUint8 ID1;

	/** Second of the header ID pair */	

	static const TUint8 ID2;

	};

/**

The CEZFileToGzipBM manages the input and output buffers for compression

@publishedAll

@released

*/

NONSHARABLE_CLASS(CEZFileToGzipBM) : public CEZFileBufferManager

	{

public:

	static CEZFileToGzipBM* NewLC(RFile &aInput, RFile &aOutput, TInt aBufferSize);

	static CEZFileToGzipBM* NewL(RFile &aInput, RFile &aOutput, TInt aBufferSize);

	/**

	Initialise the stream with input and output buffers and starts reading

	@param aZStream the stream to initialise

	*/

	virtual void InitializeL(CEZZStream &aZStream);

	/**

	Set the stream's input buffer and starts reading

	@param aZStream the steam whose input buffer to set

	*/	

	virtual void NeedInputL(CEZZStream &aZStream);

	/**

	Return the CRC - used for checking validity of the archive

	@return the CRC value

	*/	

	TInt32 Crc() const { return iCrc; } ;

private:

	CEZFileToGzipBM(RFile &aInput, RFile &aOutput);

private:

	TInt32 iCrc;

	};

/**

The CEZGzipToFileBM class manages the input and output buffers for de-compression

@publishedAll

@released

*/

NONSHARABLE_CLASS(CEZGzipToFileBM) : public CEZFileBufferManager

	{

public:

	static CEZGzipToFileBM* NewLC(RFile &aInput, RFile &aOutput, TInt aBufferSize);

	static CEZGzipToFileBM* NewL(RFile &aInput, RFile &aOutput, TInt aBufferSize);

	/**

	Finish writing to the stream

	@param aZStream the stream to complete writing to

	*/	

	virtual void FinalizeL(CEZZStream &aZStream);

	/**

	Set the stream's output buffer and start writing

	@param aZStream the steam whose output buffer to set

	*/	

	virtual void NeedOutputL(CEZZStream &aZStream);

	/**

	Return the CRC - used for checking validity of the archive

	@return the CRC value

	*/	

	TInt32 Crc() const { return iCrc; } ;

private:

	CEZGzipToFileBM(RFile &aInput, RFile &aOutput);

private:

	TInt32 iCrc;

	};

/**

A CEZGZipToFile object allows de-compression of a compressed file.

The name of the compressed file is passed into the constructor along with a target file 

to contain the uncompressed data.  The file is uncompressed by calling the InflateL() function.

@publishedAll

@released

*/

class CEZGZipToFile : public CBase

	{

public:

	~CEZGZipToFile();

	IMPORT_C static CEZGZipToFile* NewLC(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize = 0x8000);

	IMPORT_C static CEZGZipToFile* NewL(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize = 0x8000);

	IMPORT_C void ResetL(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize = 0x8000);

	IMPORT_C TBool InflateL();

private:

	CEZGZipToFile();

	void ConstructL(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize);

	void InitialiseBufManL(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize);

private:

	CEZDecompressor *iDecompressor;

	CEZGzipToFileBM *iBufferManager;

	TEZGZipTrailer iTrailer;

	RFile iGZipFile;

	TEZGZipHeader iHeader;

	};

/**

A CEZFileToGZip object allows compression of an uncompressed file to a zip file.

The uncompressed source file is passed into the constructor along with the name of the target

zip file.  The file is compressed by calling the DeflateL() function.

@publishedAll

@released

*/

class CEZFileToGZip : public CBase

	{

public:

	~CEZFileToGZip();

	IMPORT_C static CEZFileToGZip* NewLC(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize = 0x8000);

	IMPORT_C static CEZFileToGZip* NewL(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize = 0x8000);

	IMPORT_C void ResetL(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize = 0x8000);

	IMPORT_C TBool DeflateL();

private:

	CEZFileToGZip();

	void ConstructL(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize);

	void InitialiseBufManL(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize);

private:

	CEZCompressor *iCompressor;

	CEZFileToGzipBM *iBufferManager;

	TInt iUncompressedDataSize;

	RFile iGZipFile;

	TEZGZipHeader iHeader;

	};

#endif