// Copyright (c) 2006-2009 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:

// GZIP output stream functions

//

#include "xmlenggzipfileoutputstream.h"

#include <ezstream.h>

#include <ezcompressor.h>

/**

 * Default input buffers size.

 */

const TInt CXmlEngGZIPFileOutputStream::KDefaultInputBufferSize = 4096;

/**

 * Output buffer size. It determines, how often output data will be written

 * to disk. (it's written to disk, when buffer is full.

 *

 */

const TInt CXmlEngGZIPFileOutputStream::KOutputBufferSize = 0x8000;

CXmlEngGZIPFileOutputStream* CXmlEngGZIPFileOutputStream::NewLC( RFile& aOutputFile, 

                                                                RFs& aRFs )

    {

    CXmlEngGZIPFileOutputStream* gzfos = new (ELeave) CXmlEngGZIPFileOutputStream( aOutputFile, 

	                                                                                aRFs );

    CleanupStack::PushL( gzfos );

    gzfos->ConstructL();

    return gzfos;	

    }

CXmlEngGZIPFileOutputStream* CXmlEngGZIPFileOutputStream::NewL( RFile& aOutputFile, 

                                                                RFs& aRFs )

    {

    CXmlEngGZIPFileOutputStream* gzfos = CXmlEngGZIPFileOutputStream::NewLC( aOutputFile, 

	                                                                                aRFs );

    CleanupStack::Pop( gzfos );

    return gzfos;	

    }

CXmlEngGZIPFileOutputStream::CXmlEngGZIPFileOutputStream( RFile& aOutputFile, RFs& aRFs )

    {

    iKeepGoing = ETrue;

    iOutputFile = aOutputFile;

    iRFs = aRFs;

    iCrc = crc32( iCrc, NULL, 0 );

    }

void CXmlEngGZIPFileOutputStream::ConstructL()

    {

    EZGZipFile::WriteHeaderL( iOutputFile, iHeader );

    //we can't create compressor here, because we heve no input at this moment

    iOutputDescriptor.CreateL( KOutputBufferSize );

    iInputDescriptor.CreateL( KDefaultInputBufferSize );

    iOldInputDescriptor.CreateL( KDefaultInputBufferSize );

    }

CXmlEngGZIPFileOutputStream::~CXmlEngGZIPFileOutputStream()

    {

    delete iCompressor;

    iOutputDescriptor.Close();

    iInputDescriptor.Close();

    iOldInputDescriptor.Close();

    }

TInt CXmlEngGZIPFileOutputStream::Write( const TDesC8& aBuffer )

    {

    TRAP ( iError, WriteL( aBuffer ) );

    if ( iError )

        {

        return KErrNotFound;

        }

    TInt bufferSize = aBuffer.Size();

    iUncompressedDataSize += bufferSize;

    return bufferSize;

    }

void CXmlEngGZIPFileOutputStream::WriteL( const TDesC8& aBuffer )

    {

    iNoInputNeeded = ETrue;

    if ( !iCompressor )

        {

        const TInt newLength = aBuffer.Length();

        if ( newLength > iInputDescriptor.MaxLength() )

            {

            iInputDescriptor.ReAllocL( newLength );

            }

        iInputDescriptor.Copy( aBuffer );

        iCompressor = CEZCompressor::NewL( *this, CEZCompressor::EDefaultCompression,

		                                                             -CEZCompressor::EMaxWBits );    

        }

    else

        {

        iInputDescriptor.Swap( iOldInputDescriptor );

        const TInt newLength = aBuffer.Length();

        if ( newLength > iInputDescriptor.MaxLength() )

            {

            iInputDescriptor.ReAllocL( newLength );

            }

        iInputDescriptor.Copy( aBuffer );		    

        while ( iNoInputNeeded )

            {

            iCompressor->DeflateL();

            }		        

        }       		

    }

TInt CXmlEngGZIPFileOutputStream::Close()

    {

    iCloseInvoked = ETrue;

    if ( iError )

		    {

	        return -1;

		    }

    TRAP ( iError, CloseL() );

    if ( iError )

        {

        return KErrNotFound;

        }		

    return KErrNone;

    }

void CXmlEngGZIPFileOutputStream::CloseL()

    {

    while ( iKeepGoing )

        {

        iKeepGoing = iCompressor->DeflateL();

        }

    TEZGZipTrailer trailer( iCrc, iUncompressedDataSize );

    EZGZipFile::WriteTrailerL( iOutputFile, trailer );

    }

TInt CXmlEngGZIPFileOutputStream::CheckError()

    {

    return iError;

    }

void CXmlEngGZIPFileOutputStream::InitializeL( CEZZStream& aZStream )

    {

    aZStream.SetInput(iInputDescriptor);

    aZStream.SetOutput(iOutputDescriptor);

    iCrc = crc32(iCrc,iInputDescriptor.Ptr(),iInputDescriptor.Size());

    iNoInputNeeded = EFalse;

    }

void CXmlEngGZIPFileOutputStream::NeedInputL( CEZZStream& aZStream )

    {

    if ( iCloseInvoked )

        {

        aZStream.SetInput( KNullDesC8 );

        iCrc = crc32( iCrc, (unsigned char*)18, 0 );    

        //second argument can't be null, and third should be 0 !!!

        }

    else        

        {

        aZStream.SetInput( iInputDescriptor );

        iCrc = crc32( iCrc, iInputDescriptor.Ptr(), iInputDescriptor.Size() );

        iNoInputNeeded = EFalse;

        }

    }

void CXmlEngGZIPFileOutputStream::NeedOutputL( CEZZStream& aZStream )

    {

    TPtrC8 od = aZStream.OutputDescriptor();    	

    User::LeaveIfError( iOutputFile.Write(od) );

    aZStream.SetOutput( iOutputDescriptor );

    }

void CXmlEngGZIPFileOutputStream::FinalizeL( CEZZStream& aZStream )

    {

    TPtrC8 od = aZStream.OutputDescriptor();    	

    User::LeaveIfError( iOutputFile.Write(od) );    

    }