// Copyright (c) 1999-2009 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:

// Implementation for a CActive based class that monitors for low disk space

// and is informed when a PDU is being received. Should memory be too low,

// an error code is returned causing a NAck. The class will then monitor

// for the point at which PDUs can be received again, and a Resume Reception

// will be sent to the network.

// The are two limits - a high limit for general SMSs and a low limit for

// class 0 SMSs. However there is only one way to resume reception of SMSs. So

// once a resume reception is sent, it resumes hoth types of SMSs. The algorithm

// is a bit simiplier because of this:

// IF sending non-Class 0 AND we are below the high limit THEN

// N'Ack SMS

// IF not waiting for free diskspace THEN

// Wait for free diskspace to rise above the high limit

// Resume SMS Reception.

// ELSE

// Continue waiting for either high limit or low limit

// Resume SMS Reception as previously intended

// END_IF

// ELSE IF sending Class 0 AND we are below the low limit THEN

// Wait for free diskspace to rise above the low limit

// Resume SMS Reception.

// END_IF

// Note that in the second and last case, SMS reception may be resumed before

// we are above the high limit, but in that case montioring will repeat when

// the next non-class 0 SMS is attempted to be delivered. This is necessary as

// there is no way to resume just class 0 SMSs.

// 

//

/**

 @file

 @internalComponent 

*/

#include <barsc.h>

#include <bautils.h>

#include "smspcomm.h"

#include "smspmondsk.h"

#include "smsstacklog.h"

#include "smspmain.h"

#include "smspver.h"

#include <smsu.rsg>

_LIT(KSmsResourceFile, "sms\\smsu.rsc");

/**

 *  2 phase constructor.

 *  

 *  @leave Leaves if not enough memory is available.

 *  

 *  @return a newly created CSmsMonitorDiskSpace object.

 */

CSmsMonitorDiskSpace* CSmsMonitorDiskSpace::NewL(MSmsComm& aSmsComm, RMobileSmsMessaging& aSmsMessaging,RFs& aFs)

	{

	LOGSMSPROT1("CSmsMonitorDiskSpace::NewL()");

	CSmsMonitorDiskSpace*  self = new(ELeave) CSmsMonitorDiskSpace(aSmsComm, aSmsMessaging, aFs);

	CleanupStack::PushL(self);

	self->ConstructL();

	CleanupStack::Pop();

	return self;

	} // CSmsMonitorDiskSpace::NewL

/**

 *  Private constructor used in the first phase of construction.

 */

CSmsMonitorDiskSpace::CSmsMonitorDiskSpace(MSmsComm& aSmsComm, RMobileSmsMessaging& aSmsMessaging,RFs& aFs)

  : CActive(KSmsSessionPriority),

	iState(ESmsMonitorDiskSpaceIdle),

	iSmsMessaging(aSmsMessaging),

	iFs(aFs),

	iSmsComm(aSmsComm),

	iLowLimit(8*1024),

	iHighLimit(16*1024)

	{

	CActiveScheduler::Add(this);

	} // CSmsMonitorDiskSpace::CSmsMonitorDiskSpace

/**

 *  Destructor.  Ensures any outstanding operation is cancelled.

 */

CSmsMonitorDiskSpace::~CSmsMonitorDiskSpace()

	{

    Cancel();

#ifdef _DEBUG    

    iFreeDiskSpaceProperty.Close();

#endif

	} // CSmsMonitorDiskSpace::~CSmsMonitorDiskSpace

/**

 *  Initialize values for LowLimitDiskSpace and HighLimitDiskSpace

 *  from resource file

 */

void CSmsMonitorDiskSpace::ConstructL()

	{

	RResourceFile  resourceFile;

	TFileName  fileName;

	Dll::FileName(fileName);

	TParse  parse;

	TFileName  resourceFileName;

	//

	// Create the path to the resource file...

	//

	iFs.PrivatePath(resourceFileName);

	resourceFileName.Append(KSmsResourceFile);

	parse.Set(resourceFileName, &fileName, 0);

	fileName = parse.FullName();

	BaflUtils::NearestLanguageFile(iFs, fileName);

	//

	// To enable adequate CSmsMonitorDiskSpace testing we allow the SMSU.RSC

	// file to be loaded from the C: drive if it exists. This is only for a

	// DEBUG version of course! Later WINSCW is also added to allow the testing

	// on WINSCW UREL version.

	//

#if (defined __WINSCW__) || (defined _DEBUG)

	TUint  attValue;

	TChar  oldDriveLetter = fileName[0];

	//

	// Change the filename to look on C: and then see if it exists...

	//	

	fileName[0] = 'C';

	if (iFs.Att(fileName, attValue) != KErrNone)

		{

		//

		// The file does not exist on C: so revert the change...

		//

		fileName[0] = oldDriveLetter;

		}

#endif

	//

	// Log the filename in use and whether it is ROM based...

	//

#ifdef _SMS_LOGGING_ENABLED

	TBuf8<KMaxFileName>  buf8;

	buf8.Copy(fileName);

	LOGSMSPROT2("CSmsMonitorDiskSpace::ConstructL(): fileName=\"%S\"", &buf8);

#endif

    if (iFs.IsFileInRom(fileName) == NULL)

    	{

     	LOGSMSPROT1("CSmsMonitorDiskSpace::ConstructL(): Smsu.rsc not in ROM");

     	}

	//

	// Read the low and high limits...

	//

	TResourceReader  reader;

	HBufC8*  buf;

	resourceFile.OpenL(iFs, fileName);

	CleanupClosePushL(resourceFile);

	buf = resourceFile.AllocReadLC(R_LOWLIMIT_DISKSPACE_HOLDER);

	reader.SetBuffer(buf);

	iLowLimit = reader.ReadInt32();

	CleanupStack::PopAndDestroy(buf);

	buf = resourceFile.AllocReadLC(R_HIGHLIMIT_DISKSPACE_HOLDER);

	reader.SetBuffer(buf);

	iHighLimit=reader.ReadInt32();

	CleanupStack::PopAndDestroy(buf);

	CleanupStack::PopAndDestroy(&resourceFile);

#ifdef _DEBUG    

    TInt  freeSpace;

    TInt err = RProperty::Get(KUidPSSMSStackCategory, KUidPSSMSStackFreeDiskSpaceKey, freeSpace);

    if (err == KErrNone)

        {

        iInOODTesting = ETrue;

        TInt ret = iFreeDiskSpaceProperty.Attach(KUidPSSMSStackCategory, KUidPSSMSStackFreeDiskSpaceKey);

        if (ret != KErrNone)

            {

            LOGSMSPROT2("iFreeDiskSpaceProperty.Attach(): error=%d", ret);

            User::Leave(ret);

            }                        

        }   

#endif        

	LOGSMSPROT3("CSmsMonitorDiskSpace::ConstructL(): iLowLimit=%d, iHighLimit=%d",

			    iLowLimit, iHighLimit);

	} // CSmsMonitorDiskSpace::ConstructL

/**

 *  Handles a completed disk monitor or resume request.

 */

void CSmsMonitorDiskSpace::RunL()

	{

	LOGSMSPROT3("CSmsMonitorDiskSpace:RunL(): iStatus=%d, iState=%d",

	            iStatus.Int(), iState );

	switch (iState)

		{

		case ESmsMonitorDiskSpaceMonitorLowLimit:

			{

		 	iState = ESmsMonitorDiskSpaceIdle;

			//

			// If the disk space has gone above the low limit, then

			// resume reception. Otherwise (assuming the notify was

			// successful) then start monitoring the low limit again...

			//

		 	TInt  freeDiskSpace = GetFreeDiskSpace();

			if (freeDiskSpace >= iLowLimit)

				{

				ResumeSmsReception();

				}

			else if (iStatus.Int() == KErrNone)

				{

				NotifyDiskSpace(iLowLimit, ESmsMonitorDiskSpaceMonitorLowLimit);

				}

		 	}

		 	break;

		case ESmsMonitorDiskSpaceMonitorHighLimit:

			{

		 	iState = ESmsMonitorDiskSpaceIdle;

			//

			// If the disk space has gone above the high limit, then

			// resume reception. Otherwise (assuming the notify was

			// successful) then start monitoring the high limit again...

			//

		 	TInt  freeDiskSpace = GetFreeDiskSpace();

			if (freeDiskSpace >= iHighLimit)

				{

				ResumeSmsReception();

				}

			else if (iStatus.Int() == KErrNone)

				{

				NotifyDiskSpace(iHighLimit, ESmsMonitorDiskSpaceMonitorHighLimit);

				}

		 	}

		 	break;

		case ESmsMonitorDiskSpaceResumeReception:

			{

			//

			// We are finished. However, check if any N'Acks were sent between

			// the time we began the resume and now incase we need to restart

			// the monitoring.

			//

			if (iNAckdClassZero)

				{

				NotifyDiskSpace(iLowLimit, ESmsMonitorDiskSpaceMonitorLowLimit);

				}

			else if (iNAckdClassOther)

				{

				NotifyDiskSpace(iHighLimit, ESmsMonitorDiskSpaceMonitorHighLimit);

				}

			else

				{

				iState = ESmsMonitorDiskSpaceIdle;

				}

			}

			break;

		default:

			{

		 	SmspPanic(KSmspPanicUnexpectedState);

		 	}

			break;

		}

	} // CSmsMonitorDiskSpace::RunL

/**

 *  Handles a request to cancel the current state machine operation.

 */

void CSmsMonitorDiskSpace::DoCancel()

	{

	LOGSMSPROT2("CSmsMonitorDiskSpace::DoCancel(): iState=%d", iState);

    switch (iState)

		{

		case ESmsMonitorDiskSpaceIdle:

			{

			// NOP

			}

	 		break;

		case ESmsMonitorDiskSpaceMonitorLowLimit:

		case ESmsMonitorDiskSpaceMonitorHighLimit:

			{

#ifdef _DEBUG			

			if (iInOODTesting)

			    {

			    iFreeDiskSpaceProperty.Cancel();			    

			    }

			else

#endif			    

                {

                iFs.NotifyDiskSpaceCancel();

                }

		 	}

		 	break;

		case ESmsMonitorDiskSpaceResumeReception:

			{

		   	iSmsMessaging.CancelAsyncRequest(EMobileSmsMessagingResumeSmsReception);

			}

			break;

		default:

			{

		 	SmspPanic(KSmspPanicUnexpectedState);

		 	}

		}

	iState = ESmsMonitorDiskSpaceIdle;

	} // CSmsMonitorDiskSpace::DoCancel

/**

 *  Checks for enough disk space, and starts monitoring disk space if needed.

 */

void CSmsMonitorDiskSpace::CheckDiskSpaceForPDUL(TBool aPDUIsClass0)

	{

	LOGSMSPROT2("CSmsMonitorDiskSpace::CheckDiskSpaceForPDUL(): aPDUIsClass0=%d",

				aPDUIsClass0);

	//

	// First check the actual disk space before working out what to do.

	// 

	// If enough space exists, then we don't need to do anything else (even if

	// we where previously monitoring, because that will be handled later as

	// it would without this function call).

	//

	TInt  freeDiskSpace = GetFreeDiskSpace();

	if (freeDiskSpace >= iHighLimit  ||

		(freeDiskSpace >= iLowLimit  &&  aPDUIsClass0))

		{

		//

		// There is enough space for the PDU, so nothing more to do.

		//

		return;

		}

	//

	// There is not enough diskspace so record that a PDU will be N'Ack'd.

	//

	if (aPDUIsClass0)

		{

		iNAckdClassZero = ETrue;

		}

	else

		{

		iNAckdClassOther = ETrue;

		}

	//

	// Ensure we are monitoring the disk space. This will then cause a

	// ResumeReception() to be sent when the disk space increases above the

	// appropriate limit.

	//

    if (freeDiskSpace < iLowLimit)

    	{

    	//

    	// Start montioring the low limit, if not already monitoring or if

    	// we are currently monitoring the high limit.

    	//

		if (iState == ESmsMonitorDiskSpaceIdle  ||

			iState == ESmsMonitorDiskSpaceMonitorHighLimit)

			{

	    	NotifyDiskSpace(iLowLimit, ESmsMonitorDiskSpaceMonitorLowLimit);

	    	}

		}

    else // (freeDiskSpace < iHighLimit)

    	{

    	//

    	// Start monitoring the high limit if not already monitoring...

    	//

		if (iState == ESmsMonitorDiskSpaceIdle)

			{

	    	NotifyDiskSpace(iHighLimit, ESmsMonitorDiskSpaceMonitorHighLimit);

	    	}

    	}

	//

	// Imform the caller that the SMS should be N'Ack'd...

	//

	User::Leave(KErrDiskFull);

	} // CSmsMonitorDiskSpace::CheckDiskSpaceForPDUL

/**

 *  Starts monitoring the free disk space to spot when it rises above the

 *  requested limit.

 *

 *  Unfortunately the File System API does not distiguish between going below

 *  or above a limit, so some checking is needed to ensure that the correct

 *  behaviour is requested, since it is possible in theory for the disk space

 *  to change between the calls.

 *

 *  In theory this is unlikely since the priority of the SMS Stack is higher

 *  but not impossible to happen. We guard against it anyway since the mere

 *  fact it could happen poses questions when the defects come in from handsets.

 *

 *  @note The current disk space is assumed to be below the limit requested.

 *        If it is found to be above, this will cause an imediate completion.

 *

 *  @param aLimit  Limit to monitor.

 *  @param aState  State to transition to when this request is made.

 */

void CSmsMonitorDiskSpace::NotifyDiskSpace(TInt aLimit,

										   TSmsMonitorDiskSpaceState aState)

	{

	LOGSMSPROT3("CSmsMonitorDiskSpace::NotifyDiskSpace(): aLimit=%d, aState=%d",

				aLimit, aState);

	//

	// Cancel any previously outstanding requests...

	//

	if (iState != ESmsMonitorDiskSpaceIdle)

		{

		Cancel();

		}

	//

	// Start the notification...

	//

	iState = aState;

#ifdef _DEBUG	

	if (iInOODTesting)

        {

        iFreeDiskSpaceProperty.Subscribe(iStatus);

        }

    else

#endif                

        {

        iFs.NotifyDiskSpace(aLimit, EDriveC, iStatus);

        }	

	iSmsComm.DiskSpaceMonitorStateChange(ESmsDiskSpaceFull);

	SetActive();

	//

	// Now, as a sanity check, check the diskspace again. If the disk space

	// has advanced above the limit in the time between the request and now,

	// or since the last call to GetFreeDiskSpace() then the request will

	// either be invalid, or have completed. If either of these are the case

	// we need to control the situation and ensure a completion occurs...

	//

	TInt  freeDiskSpace = GetFreeDiskSpace();

	if (freeDiskSpace > aLimit)

		{

		//

		// Cancel the request...

		//

		Cancel();

		//

		// Force a fake completion for this state...

		//

		TRequestStatus*  status = &iStatus;

		iState = aState;

		iStatus = KRequestPending;

		SetActive();

		User::RequestComplete(status, KErrNone);

		}

	} // CSmsMonitorDiskSpace::NotifyDiskSpace

/**

 *  Performs the required actions for the case when leaving either the low

 *  limit or the high limit. It doesn't really matter which limit you are

 *  leaving since the resume applies for all SMSs. This gives three scenarios:

 *

 *      1) You leave the high limit. This is not a problem as all SMSs can

 *         now be received.

 *      2) You leave the low limit and go above the high limit. This is also

 *         not a problem as all SMSs can be received.

 *      3) You leave the low limit but stay below the high limit. In this case

 *         the N'Ack'd SMS was class 0 and you can now receive it. A non-class 0

 *         SMS may attempt to be delivered, but monitoring will restart as

 *         before. So again no problem.

 */

void CSmsMonitorDiskSpace::ResumeSmsReception()

	{

	LOGSMSPROT1("CSmsMonitorDiskSpace::ResumeSmsReception");

	//

	// Cancel any previously outstanding requests...

	//

	if (iState != ESmsMonitorDiskSpaceIdle)

		{

		Cancel();

		}

	//

	// Clear the N'Ackd flags...

	//