/*

* Copyright (c) 2008 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:   Base class for AppInfo and PackageInfo arrays

*

*/

#ifndef C_APPMNGR2INFOARRAY_H

#define C_APPMNGR2INFOARRAY_H

#include <e32base.h>                    // CBase

#include <appmngr2infobase.h>           // CAppMngr2InfoBase

#include "appmngr2infoarrayobserver.h"  // MAppMngr2InfoArrayObserver

/**

 * CAppMngr2InfoArray contains list of installation files or installed apps.

 * CAppMngr2Model uses these arrays to hold data received from scanning

 * installation directories or application registeries. Application UI uses

 * these arrays (via CAppMngr2Model) to get info about displayed items.

 * Functions At() and Count() are used for this purpose. Changes in array

 * content are notified using interface MAppMngr2InfoArrayObserver, and

 * makes the Application UI to refresh displayed lists.

 *

 * A "cache" buffer is used to maintain old data while new data is collected. 

 * For example, new installation files found in scanning are stored in iArray,

 * and old content is used from iCache while the scanning is on-going and more

 * items are added to iArray. When the scanning completes, new content in

 * iArray is taken in use (old content in iCache is discarded) and UI is

 * notified about the change.

 * 

 * Notifications can be disabled temporarily, which means that cache is

 * locked in use temporarily. When notifications are disabled, new content

 * may be received to iArray as usual, but no notifications are sent to

 * observer until notifications are enabled again. CAppMngr2Model disables

 * the notifications while a plugin specific command is running, as it needs

 * to call CommandComplete() when the running command completes. Plugin

 * specific commands (like delete or uninstall) may launch new scanning that

 * change the array content. CAppMngr2Model maintains pointer iActiveItem

 * to the item that is running the plugin specific command, and this item

 * is actually stored in iArray or iCache. If array content could change

 * while the command is run, iActiveItem might not be valid any more after

 * the command is complete and calling iActiveItem->CommandComplete()

 * might raise a KERN-EXEC panic. 

 */

class CAppMngr2InfoArray : public CBase

    {

public:     // constructor and destructor

    CAppMngr2InfoArray( MAppMngr2InfoArrayObserver& aObserver );

    ~CAppMngr2InfoArray();

public:     // new functions

    CAppMngr2InfoBase* At( TInt aIndex ) const;

    TInt Count() const;

    void IncrementCacheUseL();

    void IncrementCacheUseStartingNewRoundL();

    void DecrementCacheUse();

    void DisableRefreshNotificationsL();

    void EnableRefreshNotificationsL();

    void AddItemInOrderL( CAppMngr2InfoBase* aInfo );

    void ImmediateDelete( CAppMngr2InfoBase* aInfo );

private:    // new functions

    void MoveItemsToCacheMaintainingOrderL();

    void MoveCachedItemsToArrayInOrderL();

    void NotifyObserver();

    TBool IsCacheUsed() const;

protected:  // data

    MAppMngr2InfoArrayObserver& iObserver;

    RPointerArray<CAppMngr2InfoBase> iArray;

    RPointerArray<CAppMngr2InfoBase> iCache;

    TLinearOrder<CAppMngr2InfoBase> iAlphabeticalOrder;

    TBool iForceCacheUse;

    TBool iForceCacheUseWhenAddingComplete;

    TBool iQuickRefreshes;

    TBool iArrayChangedObserverNeedsNotification;

    TInt iUseCache;

    };

#endif  // C_APPMNGR2INFOARRAY_H