/*

* Copyright (c) 2004 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: 

*

*/

/**

 * @file 

 *

 * @internalComponent

 * @prototype

 */

#ifndef __DRIVEWATCHER_H__

#define __DRIVEWATCHER_H__

#include <e32base.h>

#include <f32file.h>

namespace Swi

{

/**

 * Observer interface called whenever a media change is detected.

 */

class MDriveObserver

	{

public:

	/// Enumeration indicating whether a card was inserted or removed

	enum TChangeType { EMediaInserted, EMediaRemoved };

	/**

	 * This function is called to indicate a media change has occurred.

	 *

	 * @param aChangeType	EInserted to indicate media has been inserted,

	 *						or ERemoved to indicate media has been removed.

	 */

	virtual void MediaChangeL(TInt aDrive, TChangeType aChangeType)=0;

	};

/**

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

 * and then notifies its observer.

 */

class CDriveWatcher : public CActive

	{

public:

	static CDriveWatcher* NewL(RFs& aFs, TInt aDrive, MDriveObserver& aObserver,TInt aPriority = EPriorityStandard);

	static CDriveWatcher* NewLC(RFs& aFs, TInt aDrive, MDriveObserver& aObserver,TInt aPriority = EPriorityStandard);

	~CDriveWatcher();

	TInt Drive() const;

private:

	CDriveWatcher(RFs& aFs, TInt aDrive, MDriveObserver& aObserver, TInt aPriority);

	void ConstructL();

// from CActive

	void DoCancel();

	void RunL();

	/// Set up change notification.

	void WaitForChangeL();

	/**

	 * Notifies the observer of the appropriate media change depending on whether

	 * media is now present on the drive we're currently watching.

	 */

	void NotifyMediaChange();

	/** 

	 * Determines if the media is present in the drive we are currently watching.

	 *

	 * @return ETrue if the media is present, EFalse otherwise.

	 */

	TBool IsMediaPresentL();

private:

	/// Not owned by this class

	RFs& iFs;

	/// Drive number we are watching

	TInt iDrive;

	/// Observer to notify of changes

	MDriveObserver& iObserver;  

	};

// inline functions from CDriveWatcher

inline TInt CDriveWatcher::Drive() const

	{

	return iDrive;

	}

} //namespace Swi

#endif // #ifndef __DRIVEWATCHER_H__