/*

* 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:  Definition of Advance Audio Encoder base class.

*

*/

#ifndef CADVANCEDAUDIOENCODER_H

#define CADVANCEDAUDIOENCODER_H

// INCLUDES

#include <e32base.h>

#include <sounddevice.h>

#include <mmfcodecimplementationuids.hrh>

// CONSTANTS

const TUid KUidConfig = {KUidMmfCodecAudioSettings};

// FORWARD DECLARATIONS

class CMMFBuffer;

class CMMFDataBuffer;

// CLASS DECLARATION

/**

* Mixin observer class to define an object capable of handling a callback from

* CAdvancedAudioEncoder objects

*

* @lib AdvancedAudioController.lib

* @since 3.0

*/

class MAdvancedAudioEncoderObserver

    {

    public:

        /**

        * Callback function from CAdvancedAudioEncoder when the specified buffer

        * has been emptied.

        * @return  -

        */

        virtual void BufferEmptied() = 0;

        /**

        * Callback function from CAdvancedAudioEncoder when the specified buffer

        * needs to be emptied. This indicates a shared buffer is to be written to

        * external storage.

        * @param   aBuffer an empty buffer to be refilled

        * @return  -

        */

        virtual void EmptyBuffer( CMMFBuffer* aBuffer ) = 0;

        /**

        * Callback function from CAdvancedAudioDecoder to handle specified event

        * @param   aEvent  the event to be handled

        * @return  void

        */

        virtual void SendEvent( const TMMFEvent& aEvent ) = 0;

    };

/**

*  This is the base class for all audio encoder classes.

*  It contains common behaviour for all audio encoders. The audio encoder class

*  provides the interface to audio codec.

*

*  @lib AdvancedAudioController.lib

*  @since 3.0

*/

class CAdvancedAudioEncoder : public CActive

    {

    public:

        /**

        * Destructor.

        */

        IMPORT_C virtual ~CAdvancedAudioEncoder();

    protected:

        /**

        * C++ default constructor.

        */

    	IMPORT_C CAdvancedAudioEncoder( TInt aPriority );

    public: // New functions

        /**

        * Sets the DevSound instance to be used by the audio decoder.

        * @since 3.0

        * @param aDevSound Devsound instance

        * @return void

        */

        IMPORT_C virtual void SetDevSound( CMMFDevSound& aDevSound );

        /**

        * Sets the observer object that will handle callbacks

        * @since 3.0

        * @param aObserver Observer object that will handle callbacks

        * @return void

        */

		IMPORT_C virtual void SetObserver( MAdvancedAudioEncoderObserver& aObserver );

        /**

        * Sets the sink buffer for encoding operations.

        * @since 3.0

        * @param aBuffers Pointer to shared buffers.

        * @return void

        */

        IMPORT_C virtual void SetSinkBuffers( RPointerArray<CMMFDataBuffer>* aBuffers );

        /**

        * Provides the audio encoder a buffer to process.

        * @since 3.0

        * @param   aBuffer a data buffer with data to encode.

        * @return  -

        */

        IMPORT_C virtual void EmptyBuffer( CMMFBuffer* aBuffer );

        /**

		* Sets audio decoder settings and attributes.

		* @since 3.0

        * @param   aSampleRate 			a sink sampling rate

        * @param   aNumChannel 			required number of channels (mono/stereo indication)

        * @param   aSWConvertSampleRate a sampling rate after conversion

        * @param   aSWConvertChannels   number of channels after conversion

        * @param   aCodecConfigData  	specific codec configuration data

        *

        * @return  void

        */

        IMPORT_C virtual void SetConfigL( TUint aSampleRate, TUint aChannels,

        						 TUint aSWConvertSampleRate, TUint aSWConvertChannels,

        						 const RArray<TInt>& aCodecConfigData ) = 0;

        /**

		* Sets the bit rate.

		* @since 3.0

        * @param   aBitRate 			bit rate

        * @param   aCodecConfigData  	specific codec configuration data

        *

        * @return  void

        */

        IMPORT_C virtual void SetBitRateL( TUint aBitRate, const RArray<TInt>& aCodecConfigData ) = 0;

        /**

		* Resets audio encoder settings and attributes.

		* @since 3.0

        * @return void

        */

		IMPORT_C virtual void ResetL() = 0;

        /**

	    * Check if the audio encoder is hardware accelerated.

	    * @since 3.0

	    * @return ETrue if hardare accelerated, otherwise, EFalse.

	    */

        IMPORT_C virtual TBool IsHwAccelerated() = 0;

        /**

        * Stops encoding process.

        * @since 3.0

        * @param none

        * @return void

        */

        IMPORT_C virtual void Stop();

    protected: // New functions

       /**

        * Handle emptying of the buffer received in EmptyBuffer().

        * @param   none

        * @return  void

        */

		IMPORT_C virtual void HandleEmptyBufferL() = 0;

        /**

        * Completes own request.

        */

        IMPORT_C void Ready( TInt aRequest );

       /**

        * Gets the next available shared buffer from the pool of shared buffers.

        * @param   none

        * @return  void

        */

        IMPORT_C void NextSharedBufferL();

    protected:	// Functions from base classes

        /**

        * From CActive

        */

        IMPORT_C virtual void RunL();

        /**

        * From CActive

        */

        IMPORT_C virtual void DoCancel();

    protected: // Data

		enum TAudioEncoderState

			{

			EIdle,

			EEncoding

			};

        enum TNextEvent

            {

            EDoNothing,

            EFlushBuffer,

            EPlayEnd

            };

		// Encoder state

		TAudioEncoderState iState;

		// The request being handled asynchronously

		TInt iRequest;

		// array of shared buffers

		RPointerArray<CMMFDataBuffer>* iSharedBuffers;

       	// next available buffer index

	    TInt iSharedBufferIndex;

        // audio buffer to empty pointer

        CMMFBuffer* iBufferToEmpty;

        // next available buffer pointer

        CMMFBuffer* iNextBuffer;

        // DevSound pointer

        CMMFDevSound* iMMFDevSound;

        // Audio Converter observer

        MAdvancedAudioEncoderObserver* iObserver;

	};

#endif		// CADVANCEDAUDIOENCODER_H