/*

* Copyright (c) 2000-2009 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: Monitor class for the drive that contains the message store DB.

*

*/

#ifndef _C_DRIVE_MONITOR_H

#define _C_DRIVE_MONITOR_H

//  INCLUDES

#include <e32base.h>

#include <f32file.h>

//CLASS DECLARATION

class MStoreDriveStateObserver

    {

    public:

        /**

         * aState will be true if drive is mounted and false otherwise

         */

        virtual void DriveStateChangedL( TBool aState ) = 0;

    };

/**

 * This active object waits for an indication that the media has changed

 */

NONSHARABLE_CLASS( CStoreDriveMonitor ) : public CActive

	{

public:

    /**

    * Two-phased constructor.

    */

	static CStoreDriveMonitor* NewL( MStoreDriveStateObserver& aDriveStateObserver );

    /**

    * Two-phased constructor.

    */

	static CStoreDriveMonitor* NewLC( MStoreDriveStateObserver& aDriveStateObserver );

    /**

    * Destructor

    */

	~CStoreDriveMonitor();

    /**

    * Make notification request

    */

    void WaitForChange();

    /**

     * Return true if drive is present and false otherwise.

     */

    TBool IsDrivePresent();

    /**

     * Set drive to monitor.

     */

    void SetDriveL( TDriveNumber aDrive );

private:

    /**

    * C++ default constructor

    */

	CStoreDriveMonitor( MStoreDriveStateObserver& aDriveStateObserver );

    /**

    * By default Symbian OS constructor is private.

    */

	void ConstructL();	

    /**

    * This method checks if the drive is mounted

    */

	void MediaPresentL();

// from CActive

    /**

    * This method is used when cancelling request

    */

	void DoCancel();

    /**

    * This method is used when changes in drive happens

    */

	void RunL();

	/**

	 * This is applied when a leave occur in RunL method.

	 */

	TInt RunError(TInt aError);

private:

    /**

     * File server session.

     */

	RFs iFs;

	/**

	 * Drive state observer.

	 */

	MStoreDriveStateObserver& iDriveStateObserver;

	/**

	 * Drive to monitor.

	 */

	TDriveNumber iDrive;

	/**

	 * Drive letter determined from drive number.

	 */

	HBufC* iDriveLetter;

	};

#endif      // _C_DRIVE_MONITOR_H