/*

* Copyright (c) 2002-2004 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "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:  Implements the double buffering functionality in the DownloadManager

*

*/

#include <bldvariant.hrh>

#include "FileExt.h"

#include "HttpClientApp.h"

#include "HttpDownload.h"

#include "HttpStorage.h"

#include "BuffStorage.h"

#include "HttpDownloadManagerServerEngine.h"

#include "HttpDownloadMgrLogger.h"

#include "HeaderField.h"

#include <SysUtil.h>

#include <DocumentHandler.h>

#include <APMSTD.H>

#include "HttpDownloadMgrLogger.h"

#ifdef __SYNCML_DM_FOTA

#include <fotaengine.h>

#endif

#ifdef RD_MULTIPLE_DRIVE

#include <driveinfo.h>

#endif //RD_MULTIPLE_DRIVE

// EXTERNAL DATA STRUCTURES

//extern  ?external_data;

// EXTERNAL FUNCTION PROTOTYPES  

//extern ?external_function( ?arg_type,?arg_type );

// CONSTANTS

//const ?type ?constant_var = ?constant;

// ---------------------------------------------------------

// CBuffStorage::CBuffStorage

// ---------------------------------------------------------

//

CBuffStorage::CBuffStorage( CHttpStorage* aHttpStorage )

 iDownloadedSize(aHttpStorage->iDownloadedSize), 

 iBufferedSize(aHttpStorage->iBufferedSize),

 iHttpStorageBufferSize(aHttpStorage->iBufferSize),

 iHttpStorageLength(aHttpStorage->iLength),

 iBufferingEnabled(aHttpStorage->iBufferingEnabled),

 iProgressiveDownload(aHttpStorage->iProgressiveDownload)

#ifdef __SYNCML_DM_FOTA

 ,iFotaStream(aHttpStorage->iFotaStream)

#endif // __SYNCML_DM_FOTA

    {

    }

// -----------------------------------------------------------------------------

// CBuffStorage::ConstructL

// Symbian 2nd phase constructor can leave.

// -----------------------------------------------------------------------------

//

void CBuffStorage::ConstructL()

    {

    }

// -----------------------------------------------------------------------------

// CBuffStorage::NewL

// Two-phased constructor.

// -----------------------------------------------------------------------------

//

CBuffStorage* CBuffStorage::NewL( CHttpStorage* aHttpStorage )

    {

    CBuffStorage* self = new( ELeave ) CBuffStorage( aHttpStorage );

    CleanupStack::PushL( self );

    self->ConstructL();

    CleanupStack::Pop();

    return self;

    }

// ---------------------------------------------------------

// CBuffStorage::~CBuffStorage

// ---------------------------------------------------------

//

CBuffStorage::~CBuffStorage()

    {

	ResetBuffers();

	delete iWritePtr; iWritePtr = 0;

    }

// ---------------------------------------------------------

// CBuffStorage::ResetBuffer

// ---------------------------------------------------------

//

void CBuffStorage::ResetBuffers()

	{	

	CLOG_WRITE_1("(%08X) CBuffStorage::ResetBuffers >>", this);

	// Cleanup

    delete iBuff1; iBuff1 = NULL;

    delete iBuff2; iBuff2 = NULL;

    iClientBuffer = NULL;

    iBufferSize = 0;

    CLOG_WRITE_1("(%08X) CBuffStorage::ResetBuffers <<", this);

	}

// ---------------------------------------------------------

// CBuffStorage::WriteOutNextBodyDataL

// ---------------------------------------------------------

//

TBool CBuffStorage::WriteOutNextBodyDataL( const TDesC8& aBuf )

    {

    TBool retVal( ETrue );

    if( iFile )

        {

        if( iBufferingEnabled )

            {

            DoBufferingWriteL(aBuf);

        	}

        else

        	{

        	DoNonbufferingWriteL(aBuf);

        	}

        }        

#ifdef __SYNCML_DM_FOTA                

    else if( iFotaStream )

        {

        iFotaStream->WriteL( aBuf );

        }

#endif  // __SYNCML_DM_FOTA

    if( iHttpStorageLength != KDefaultContentLength &&

        iBufferedSize > iHttpStorageLength )

        // we don't know actually how many bytes will come down.

        {

        CLOG_WRITE_1( "(%08X) CBuffStorage::WriteOutNextBodyDataL: Length modified", this);

        iHttpStorageLength = KDefaultContentLength;

        retVal = EFalse;

        }

    return retVal;

    }

// ---------------------------------------------------------

// CBuffStorage::FlushBuffersL

// ---------------------------------------------------------

//

void CBuffStorage::FlushBuffersL()

	{

	if(!iFile)

		{

		return;

		}

	CLOG_WRITE_1("(%08X) CBuffStorage::FlushBuffersL >>", this);

	// Make sure async writes are finished before doing anything

	if(iLastWriteErrorCode != KErrNone)

		{

		CLOG_WRITE_2("(%08X) CBuffStorage::FlushBuffersL: last error = %d", this, iLastWriteErrorCode);

		TInt err = iLastWriteErrorCode;

		iLastWriteErrorCode = KErrNone;

		User::Leave(err);

		}

	if(iClientBuffer)

		{

		// Flush whatever is left on the client buffer

		TInt len = iClientBuffer->Length();

		CLOG_WRITE_2("(%08X) CBuffStorage::FlushBuffersL: %d bytes", this, len);

		if(len > 0)

			{

			// Write to file

			TPtr8 des(iClientBuffer->Des());

			User::LeaveIfError(iFile->Write(des));

			// Update how much was written to file

			iDownloadedSize += len;

			des.Zero();

			}

		}

	CLOG_WRITE_1("(%08X) CBuffStorage::FlushBuffersL <<", this);

	}

// ---------------------------------------------------------

// CBuffStorage::DoBufferingWriteL

// ---------------------------------------------------------

//        

void CBuffStorage::DoBufferingWriteL(const TDesC8& aBuf)

	{	

    if(iBufferSize != iHttpStorageBufferSize)

        {

        CLOG_WRITE_3("(%08X) CBuffStorage::DoBufferingWriteL: Allocate %d - downloaded %d", this, iHttpStorageBufferSize, iBufferedSize);

        // Make sure nothing is leaked

        delete iBuff1; iBuff1 = 0;

        delete iBuff2; iBuff2 = 0;

        iBufferSize = 0;

        // Allocate buffers

        iBuff1 = HBufC8::NewL(iHttpStorageBufferSize);

        iBuff2 = HBufC8::NewL(iHttpStorageBufferSize);

		// Mark that we now have buffers that are iBufferSize big

		iBufferSize = iHttpStorageBufferSize;

        // Set client to use buffer 1

        iClientBuffer = iBuff1;

        }

	// Get incoming data pointer and size

    const TUint8* src = aBuf.Ptr();

    TInt incomingBuffSize = aBuf.Length();

    // Process the data in blocks  

	while(incomingBuffSize)

		{

		// Get pointer to current client buffer data (at start of loop since iClientBuffer can change)

		TPtr8 buff = iClientBuffer->Des();

		TInt buffLength = buff.Length();

		// How much space in the buffer

		TInt toFillUp = iBufferSize - buffLength;

		// Check if we can just fit everything in the current buffer

	    if(incomingBuffSize < toFillUp)

	        {  

	    	// Dump data on the current client buffer since ample space exists

	    	buff.Append(src, incomingBuffSize);

	    	// Update the 'received' counter on how much we got from air

	    	iBufferedSize += incomingBuffSize;

	    	CLOG_WRITE_4("(%08X) CBuffStorage::DoBufferingWriteL: Copied %d, now %d / %d", this, incomingBuffSize, buff.Length(), iBufferSize);

	    	// And break out of the loop since we're finished for this round

			break;

			}

		// At this point we have data that either fills or overflows the buffer so append as much as fits

		buff.Append( src, toFillUp );

		// Update the 'received' counter on how much we copied

		iBufferedSize+=toFillUp;

		CLOG_WRITE_4("(%08X) CBuffStorage::DoBufferingWriteL: Copied %d, now %d / %d", this, toFillUp, buff.Length(), iBufferSize);

		// Subtract how much we copied from the loop counter and advance source data pointer

		incomingBuffSize -= toFillUp;

		src+=toFillUp;

	    // Now we have a full client buffer, better do something with it

		// In case of async writes we have to check if there was error previously

		if(iLastWriteErrorCode != KErrNone)

			{

			// Clear the error code and leave with it

			TInt err = iLastWriteErrorCode;

			iLastWriteErrorCode = KErrNone;

			User::Leave(err);

			}

		if(iProgressiveDownload)

	    	{

	    	CLOG_WRITE_1("(%08X) CBuffStorage::DoBufferingWriteL: Buffer full -> Progressive download", this);

	    	TInt len = buff.Length();

	    	// Progressive download -> just do a synchronous write and update counter

	    	User::LeaveIfError(iFile->Write(buff));

	    	// Update how much was written to file (sync write)

	    	iDownloadedSize += len;

	    	// Clear out client buffer

	    	buff.Zero();

	    	// Continue for next write

	    	continue;

	    	}

		// We must keep the descriptor alive until async operations have finished

		if(!iWritePtr)

			{

			iWritePtr = new (ELeave) TPtr8(iClientBuffer->Des());

			}

		else

			{

			iWritePtr->Set(iClientBuffer->Des());

			}

#ifdef _DEBUG

		// Print out file position so we can check alignments

		TInt currentPos(0);

		iFile->Seek(ESeekCurrent, currentPos);

		CLOG_WRITE_3("(%08X) CBuffStorage::DoBufferingWriteL - Start async write %d bytes, filepos=%d", this, iWritePtr->Length(), currentPos);

#endif

		// Start the async write and set AO active

	 	// since it is not known when the buffer can be used again)

	 	if(iClientBuffer == iBuff1)

	 		{

	 		iClientBuffer = iBuff2;

	 		}

	 	else

	 		{

	 		iClientBuffer = iBuff1;

	 		}

	 	// Make sure the new client buffer is empty

	 	iClientBuffer->Des().Zero();

		}

	}

// ---------------------------------------------------------

// CBuffStorage::DoNonbufferingWriteL

// ---------------------------------------------------------

//	

void CBuffStorage::DoNonbufferingWriteL(const TDesC8& aBuf)

	{

	CLOG_WRITE_2("(%08X) CBuffStorage::DoNonbufferingWriteL: %d bytes", this, aBuf.Length());

	TInt len = aBuf.Length();

	if(len)

		{

    	User::LeaveIfError( iFile->Write( aBuf ) );

    	if( iProgressiveDownload )

        	{

        	User::LeaveIfError( iFile->Flush() );

    		}

		// Update how much received from air

		iBufferedSize += len;

		// Update how much written to file

   		iDownloadedSize += len;

   		}

    }

//  End of File