/*

* Copyright (c) 2006 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:  Plays back voice commands

*

*/

#ifndef TAGPLAYER_H

#define TAGPLAYER_H

#include <nssvasmplayeventhandler.h>

#include <nssvasmtag.h>

#include <nssvasmgettagclient.h>  // for MNssTagListArray

#include "vcommandinternalapi.h"

/**

* Plays back the voice commad

*/

class CTagPlayer : public CBase, public MNssPlayEventHandler

    {

    public:

        static CTagPlayer* NewL();

        ~CTagPlayer();

        /**

        * Attempts to play back the text expected to be recognized. 

        * This object takes ownership on the aTag and will delete it upon

        * the playback completion.

        * This function is asynchronous

        *

        * @param aTag Tag to play. Will be deleted (not from VAS) upon the 

        *        playback completion

        * @param aPlayEventHandler Entity that handles the playback callbacks

        * @see NssVasMPlayEventHandler.h

        *

        * @leave KErrBadHandle if the current command has not been retrieved 

        *        from CVCommandHandler (i.e. was not trained for recognition)

        * @leave KErrNotFound if this command cannot be found in aHandler

        * @leave KErrNotReady @see nssvasmspeechitem.h MNssSpeechItem::TNssSpeechItemResult 

        *                                              EVasUnexpectedRequest

        * @leave KErrInUse @see nssvasmspeechitem.h MNssSpeechItem::TNssSpeechItemResult 

        *                                              EVasInUse

        * @leave KErrArgument @see nssvasmspeechitem.h MNssSpeechItem::TNssSpeechItemResult 

        *                                              EVasInvalidParameter

        * @leave KErrGeneral @see nssvasmspeechitem.h MNssSpeechItem::TNssSpeechItemResult 

        *                                             EVasPlayFailed

        */

        virtual void PlayTagL( MNssTag* aTag, MNssPlayEventHandler& aPlayEventHandler );

        /**

        * Cancels playback. No PlayStarted/PlayComplete after it

        *

        * @leave KErrNotReady if playback has never been started

        */                                   

        virtual void CancelPlaybackL();

        // From MNsPlayEventHandler

        /**

        * The HandlePlayStarted method is a virtual method implemented by the

        * client and is called when play is started

        * @param aDuration - the duration of the utterance data

        */       

        virtual void HandlePlayStarted( TTimeIntervalMicroSeconds32 aDuration );

        /**

        * The HandlePlayComplete method is a virtual method implemented by the

        * client and is called when play is completed

        * @param aErrorCode EVasErrorNone if playing was successfull

        */       

        virtual void HandlePlayComplete( TNssPlayResult aErrorCode );        

    private:

        // Playback is asynchronous function. 

        // This variable is used to hold the tag being played back

        MNssTag*                    iPlaybackTag;

        // Playback is asynchronous function. 

        // This variable is used to hold the external play event

        // handler

        MNssPlayEventHandler*       iPlayEventHandler;

    };

#endif // TAGPLAYER_H