/*

* 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:  LUID buffering

*

*/

#ifndef __NSMLDSLUIDBUFFER_H__

#define __NSMLDSLUIDBUFFER_H__

// INCLUDES

#include <e32base.h>

#include <SmlDataSyncDefs.h>

#include "nsmldshostclient.h"

// FORWARD DECLARATIONS

class CNSmlDSHostClient;

class CNSmlDSContentItem;

// CLASS DECLARATION

/**

* Class for LUID (Local UID) buffering.

*

* @lib nsmldsagent.lib

*/

class CNSmlDSLUIDBuffer : public CBase 

    {

    public: // constructors and destructor

        /**

        * C++ constructor.

        * @param aHostClient Host Client used for communication with the Host Session.

        * @param aContentItem Sync content whose LUIDs are buffered.

        */

        CNSmlDSLUIDBuffer( CNSmlDSHostClient& aHostClient, CNSmlDSContentItem& aContentItem );

        /**

        * Destructor.

        */

        ~CNSmlDSLUIDBuffer();

    public: // new functions

        /**

        * Gets the current UID.

        * @param aLocalUID On return contains the current UID.

        */

        void CurrentUID( TSmlDbItemUid& aLocalUID ) const;

        /**

        * Gets the first UID and the command associated to its modification type from buffer.

        * @param aLocalUID On return contains the next UID.

        * @param aCmdName On return contains the command associated with the returned UID's

        *        modification type.

        * @return KErrNone if completed successfully or KErrEof if the buffer is empty

        */

        TInt NextUIDL( TSmlDbItemUid& aLocalUID, TDes8& aCmdName );

        /**

        * Gets the total number of UIDs, both in the buffer and written.

        * @return TInt representing the number of UIDs in the buffer.

        */

        TInt ClientItemCount() const;

        /**

        * Sets the current UID as written and removes it from the buffer.

        */

        void SetCurrentItemWritten();

        /**

        * Gets UIDs of all modified items from datastore to the buffer asynchronously.

        * @param aResultCode On return contains the result code of the operation.

        */

        void FetchModificationsL( TInt& aResultCode );

    private: // constructors & operators

        /**

        * Prohibit copy constructor.

        */

        CNSmlDSLUIDBuffer( const CNSmlDSLUIDBuffer& aOther );

        /**

        * Prohibit assignment operator.

        */

        CNSmlDSLUIDBuffer& operator=( const CNSmlDSLUIDBuffer& aOther );

    private: // data

        // internal states

        enum TState    

            {		

            EModifications = 1,

            EEnd

            };

        // current state

        TState iCurrState;		

        // array of buffered modification items

        RNSmlDbItemModificationSet iModificationSet;		

        // reference to the ds hostclient

        CNSmlDSHostClient& iHostClient;

        // reference to the current content (datastore) data

        CNSmlDSContentItem& iContentItem;

        // the number of written items

        TInt iWrittenItems;

    };

#endif // __NSMLDSLUIDBUFFER_H__

// End of File