// Copyright (c) 2004-2009 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:

// demon.h - API between main (ui) and engine for daemons

//

#ifndef __DEMON_H

#define __DEMON_H

#include <e32base.h>

/**

@file demon.h

DNS main

@internalComponent	Domain Name Resolver

*/

/**

// Services offered by the appication main to the engine.

//

// A bare bones API definition which allows to write

// the DND <b>engine</b> part without a need to make two versions

// if daemon application is with, or without the user interface.

*/

class MDemonMain

	{

public:

	/**

	// Write message to the log device.

	//

	// @param aText	to be written

	*/

	virtual void Write(const TDesC &aText) = 0;

	/*

	// Write message with format to the log device

	//

	// @param aFmt	the format string to be applied

	// @param aList	the parameters to the format string

	*/

	virtual void WriteList(const TDesC &aFmt, VA_LIST aList) = 0;

	/**

	// Write message, if error

	//

	// Just a convenience method to make it easy to write code

	// which is "mostly silent" until exceptional situations

	// occur.

	//

	// @param aText	to be written, if aResult != KErrNone

	// @param aResult	is the result code to be tested

	//

	// @return	aResult (always)

	*/

	TInt virtual CheckResult(const TDesC &aText, TInt aResult) = 0;

	};

/**

// Services offered by the engine to the application main.

*/

class MDemonEngine

	{

public:

	// Allow delete via M-class pointer

	virtual ~MDemonEngine() {}

	// Allow ConstructL via M-class pointer

	virtual void ConstructL() = 0;

	// Handle commands from the user

	virtual void HandleCommandL(TInt aCommand) = 0;

	// Create the real engine instance [there can be only one]

	static MDemonEngine *NewL(MDemonMain &aMain);

	};

#endif