/*

* Copyright (c) 2005 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:  

*       Class for cleaning up unnecessary tombstones.

*

*/

#ifndef __CMRUTILSGRAVEYARDCLEANER_H__

#define __CMRUTILSGRAVEYARDCLEANER_H__

//  INCLUDES

#include <e32base.h>

#include <calprogresscallback.h>

// FORWARD DECLARATIONS

class CMRUtilsCalDbBase;

class CCalIter;

class CCalEntry;

// CLASS DECLARATION

/**

* This class performs cleanup for tombstone database asynchronously in the

* background. Caller doesn't need to involve this after starting the operation.

* This class assumes that databases given are fully initialized.

*/

class CMRUtilsGraveyardCleaner : public CBase, public MCalProgressCallBack

    {

    public: // Data types

        /**

        * State of the cleaner object.

        */

        enum TCleanerState

            {

            ENotActive,

            EResurrectedItemsCleanup,

            ETimeLimitCleanup

            };

    public: // Constructors and destructors

        /**

        * Symbian two-phased constructor.

        * @param aNormalDb database reference

        * @param aTombsDb database reference

        * @return instantiated object

        */

        static CMRUtilsGraveyardCleaner* NewL(

            const CMRUtilsCalDbBase& aNormalDb,

            CMRUtilsCalDbBase& aTombsDb );        

        /**

        * Destructor.

        */

        ~CMRUtilsGraveyardCleaner();

    public: // New functions 

        /**

        * Starts asynchronous cleanup of tombstones which should be deleted

        * based on given history time limit, or which have been resurrected

        * and exist now in the normal database.

        * @param aTimeLimitUtc older tombstones are deleted using CCalEntryView,

        *        user should give Time::NullTTime() if no time limit is used

        */

        void StartIdleCleanupL( TTime aTimeLimitUtc ); 

        /**

        * Returns current state of the cleanup object. This method mainly

        * intended for testing purposes.     

        * @return current state

        */

        TCleanerState CurrentStateL() const;

    protected: // New functions

        /**

        * TCallback method called by the idle cleaner to perform one step.

        * @param aCleaner object, ownership not transferred

        * @return 1 if not finished, 0 if finished 

        */

        static TInt StepL( TAny* aCleaner );

        /**

        * Helper method for performing one step of clean up task.

        * @return 1 if not finished, 0 if finished 

        */

        TInt DoStepL();

        /**

        * Helper which deletes a tombstone entry if it appears to be resurrected,

        * i.e. it is found from the normal database as well.

        * @param aUid specifies entry to check

        */

        void CleanupIfResurrectedL( const TDesC8& aUid );

    protected: // From MCalProgressCallBack

    	void Progress( TInt aPercentageCompleted );

        TBool NotifyProgress();

        void Completed( TInt aError );

    protected: // Constructors and destructors

        /**

        * C++ default constructor.

        * @param aNormalDb database reference

        * @param aTombsDb database reference        

        */

        CMRUtilsGraveyardCleaner( const CMRUtilsCalDbBase& aNormalDb,

                                  CMRUtilsCalDbBase& aTombsDb );

        /**

        *  Constructor, second phase.

        */

        void ConstructL();            

    protected: // data

        // Database reference

        const CMRUtilsCalDbBase& iNormalDb;

        // Database reference

        CMRUtilsCalDbBase& iTombsDb;

        // Uid of entry currently investigated

        TPtrC8 iCurrentEntryUid;

        // State of the cleaner object

        TCleanerState iState;

        // Time criterion for cleanup

        TTime iTimeLimitUtc;

        // Idle cleaner, own            

        CIdle* iIdleCleaner;   

        // Iterator for tombstone db, own

        CCalIter* iTombsEntryIterator;        

    };

#endif // __CMRUTILSGRAVEYARDCLEANER_H__

// End of File