/*

 * Copyright (c) 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:  Contains logic for watching certain disk's space

 *

 */

#ifndef CIRDISKSPACEOBSERVER_H

#define CIRDISKSPACEOBSERVER_H

#include <e32base.h>  // CActive

#include <f32file.h>  // RFs

class MIRDiskSpaceObserverInterface;

/**

 * Defines disk space observer. 

 *

 * Observers defined disk and notifies observer if disk space drops below

 * certain level.

 */

class CIRDiskSpaceObserver : public CActive

{

public:

    /**

     * Static constructor 

     *

     * @param aObserver Observer who is interested if disk 

     * space drops below certain level.

     */

    static CIRDiskSpaceObserver* NewL(MIRDiskSpaceObserverInterface* aObserver);

    /**

     * Destructor

     */

    ~CIRDiskSpaceObserver();

    /**

     * Start Monitoring 

     */

    void Start(const TInt64 aCriticalLevel);

    /**

     * Tells observed critical level.

     *

     * @return critical level which is been observed by this session.

     */

    TInt64 CriticalLevel() const;

    /**

     * Returns whether or disk defined by parameter 

     * contains less than the critical level free disk space.

     */

    TBool IsBelowCriticalLevel(const TInt64 aCriticalLevel) const;

protected:

    /**

     * From CActive 

     */

    void DoCancel();

    void RunL();

private:

    /**

     * C++ constructor.  

     */

    CIRDiskSpaceObserver(MIRDiskSpaceObserverInterface* aObserver);

    /**

     * Second phase constructor

     */

    void ConstructL();

    void Run();

private:

    /** 

     * The observer to be notified when critical disk space limit is reached. 

     */

    MIRDiskSpaceObserverInterface* iObserver;

    /** 

     * Critical disk space level. 

     */

    TInt64 iCriticalLevel;

    /** 

     * Handle to the file system. 

     */

    RFs iFs;

};

#endif // CIRDISKSPACEOBSERVER_H