/*

* 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:  Private change finder header

*

*/

#ifndef __CHANGEFINDER_H__

#define __CHANGEFINDER_H__

// INCLUDES

#include <msvids.h>

#include <nsmlchangefinder.h>

#include "snapshotitem.h"

// DATATYPES

typedef CArrayFixSeg<TSnapshotItem> CSnapshotArray;

// Granularity used with dynamic array

const TInt KSnapshotGranularity = 32;

// CLASS DECLARATION

/**

* @brief CChangeFinder Class

* This is a ChangeFinder class, which can be used to track down changes in the message store.

* It's functionality is equal to CSmlChangeFinder, except the functionality is a bit wider

* since this class can also detect "partially updated" items. It means that if only the status

* Bits of the message are changed, it can be detected. It is achieved by using TSnapshotItem

* class, which contain also this information. Because neither of these classes contained virtual

* functionality, the functionality of this class couldn't be inherited from the CSmlChangeFinder

*/

class CChangeFinder : public CBase

	{ 

public:

	/**

    * Class constructor, Creates a new class instance.

    *

    * @param aSyncRelationship  IN: Reference to MSmlSyncRelationship interface.

    * @param aKey               IN: Key that is used in sorting snapshot.

    * @param aStreamUid         IN: Snapshot stream UID.

    * @return CChangeFinder*, New ChangeFinder instance.

    */

    static CChangeFinder* NewL( MSmlSyncRelationship& aSyncRelationship, 

                               TKeyArrayFix aKey,

                               TBool& aHasHistory, 

                               TInt aStreamUid = KNSmlDefaultSnapshotStreamUID );

    /**

    * Class destructor.

    */

	~CChangeFinder();

    /**

    * Close ChangeFinder object, stores snapshot.

    */

	void CloseL();

    /**

    * Reset change information, makes all content new from ChangeFinder point of view.

    */

	void ResetL();

    /**

    * Find changed items by comparing snapshots.

    * 

    * @param aChangedUids   IN: Array for results.

    */

	void FindChangedItemsL( CNSmlDataItemUidSet& aChangedUids );

    /**

    * Find deleteed items by comparing snapshots.

    * 

    * @param aDeletedUids   IN: Array for results.

    */

	void FindDeletedItemsL( CNSmlDataItemUidSet& aDeletedUids );

    /**

    * Find new items by comparing snapshots.

    * 

    * @param aNewUids   IN: Array for results.

    */	

	void FindNewItemsL(CNSmlDataItemUidSet& aNewUids);

    /**

    * Find moved items by comparing snapshots.

    * 

    * @param aMovedUids   IN: Array for results.

    */	

	void FindMovedItemsL( CNSmlDataItemUidSet& aMovedUids );

    /**

    * Add item to snapshot, it is no loger reported.

    * 

    * @param aItem   IN: item to add.

    */

	void ItemAddedL( const TSnapshotItem& aItem );

    /**

    * Delete item from snapshot, it is no loger reported.

    * 

    * @param aItem   IN: item to delete.

    */

	void ItemDeletedL( const TSnapshotItem& aItem );

    /**

    * Update item to snapshot, it is no loger reported.

    * 

    * @param aItem   IN: item to update.

    */

	void ItemUpdatedL( const TSnapshotItem& aItem );

    /**

    * Move item within snapshot, it is no loger reported.

    * 

    * @param aItem   IN: item to move.

    */

	void ItemMovedL( const TSnapshotItem& aItem );

    /**

    * Commit all changes to snapshot, there's nothing to report anymore.

    */

	void CommitChangesL();

    /**

    * Commit a set of items to snapshot, these items won't be reported anymore.

    * 

    * @param aUids   IN: a set of items to commit.

    */

	void CommitChangesL( const MSmlDataItemUidSet& aUids );

	/**

    * Sets new snapshot to compare against.

    * 

    * @param aNewSnapshot   IN: a new snapshot.

    */

	void SetNewSnapshot( CSnapshotArray* aNewSnapshot );

	/**

    * Retrieves DataStore id number.

    *

    * @return TInt64, DataStore id.

    */

	TInt64 DataStoreUid() const;

	/**

    * Sets DataStore id number.

    * 

    * @param aUid   IN: a new datastore id.

    */

	void SetDataStoreUid( TInt64 aUid );

    /**

    * Checks whether specific item can be partially updated.

    * 

    * @param aUid   IN: item id.

    * @return TBool Result, ETrue if the item contains only status change (read<->unread).

    */

	TBool UpdatePartialL( TSmlDbItemUid& aUid );

protected:

    /**

    * C++ Constructor

    *

    * @param aSyncRelationship  IN: Reference to MSmlSyncRelationship interface.

    * @param aKey               IN: Key that is used in sorting snapshot.

    * @param aStreamUid         IN: Snapshot stream UID.

    */    

	CChangeFinder( MSmlSyncRelationship& aSyncRelationship, 

	              TKeyArrayFix aKey, 

	              TInt aStreamUid );

    /**

    * 2nd-phase Constructor

    *

    * @param aHasHistory   IN: ETrue, if there was synchronization history.

    */    

    void ConstructL( TBool& aHasHistory );

private:

    /**

    * Allows access to streams.

    */

	MSmlSyncRelationship& iSyncRelationship;

    /**

    * New snapshot to compare against.

    */	

	CSnapshotArray* iCurrentSnapshot;

    /**

    * Current snapshot.

    */

	CSnapshotArray* iOldSnapshot;

    /**

    * Key that is used in sorting snapshot.

    */

	TKeyArrayFix iKey;

    /**

    * Stream id number to access sync relationship.

    */	

	TInt iStreamUid;

    /**

    * Data store id number.

    */	

	TInt64 iDataStoreUid;

    };

#endif // __CHANGEFINDER_H__