/*

* Copyright (c) 2004-2006 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:    Formatter classes for decoding of RTP payload format

*                for AMR ( narrow band ) and AMR-WB ( wide band ) audio codecs.

*

*/

#ifndef AMRPAYLOADENCODER_H

#define AMRPAYLOADENCODER_H

// INCLUDES

#include <e32std.h>

#include "amrpayloadformatter.h"

#include "amrpayloadheader.h"

#include "amrtocentry.h"

#include "streamformatter.h"

// CONSTANTS

// MACROS

// DATA TYPES

// FUNCTION PROTOTYPES

// FORWARD DECLARATIONS

class TStreamEncoder;

// CLASS DECLARATION

/**

* The AMR payload encoder for bandwidth efficient mode.

*

* @lib <TBD>

* @since Series-60 2.1

*/

class CAmrPayloadEncoder : public CAmrPayloadFormatter

    {

    public:  // Constructors and destructor

         /**

        * Two-phased constructor.

        */

        static CAmrPayloadEncoder* NewL( TBool aIsNb );

        /**

        * Destructor.

        */

        virtual ~CAmrPayloadEncoder( );

    public: // Functions

        /**

        * Set AMR codec mode request ( CMR ).

        * @since    Series-60 2.1

        * @param    aRequest - [input] AMR codec mode request ( CMR )

        * @return   void

        */

        void SetModeRequest( TAmrModeRequest aRequest );

        /**

        * Encode a received AMR frame into the payload buffer.

        * @since Series-60 2.1

        * @param aChannel - [input] Channel number that the frame belongs to

        * @param aFrameType - [input] Frame type

        * @param aFrameQualityInd - [input] Frame quality indicator bit; 1 if frame OK; 0 if frame damaged

        * @param aFrameData - [input] Frame data; its length depends on frame type

        * @return   ETrue if payload formatting is completed; otherwise EFalse

        */

        virtual TBool EncodeFrame( TInt aChannel, 

                                   TAmrFrameType aFrameType, 

                                   TUint8 aFrameQualityInd, 

                                   const TDes8& aFrameData );

        /**

        * Reset the payload buffer.

        * @since    Series-60 2.1

        * @param    None

        * @return   void

        */

        void ResetPayloadBuffer( );

        /**

        * Do bit shifting when AmrPayloadFormatPlugin is doing buffer flushing.

        * @since    Series-60 2.1

        * @param    None

        * @return   ETrue if payload formatting is completed; otherwise EFalse

        */

        TBool ReEncodeFrameL( );

         /**

        * Do bit shifting when AmrPayloadFormatPlugin is doing buffer flushing

        * @since    Series-60 2.1

        * @param    aBuffer Buffer containing frame data

        * @return   ETrue if payload formatting is completed; otherwise EFalse

        */

        TBool ReEncodeFrameL( TUint8* aBuffer );

        /**

         * Returns ETrue if next frame will start new packetization period.

         * @since    Series 60 3.1

         * @return   ETrue if next frame starts new period

         */

        TBool IsStartOfPeriod();

    public: // Functions from CAmrPayloadFormatter

        /**

        * Set number of audio channels.

        * @since    Series-60 2.1

        * @param    aChannelCount - [input] Number of audio channels

        * @return   KErrNone if successful; system wide error code otherwise

        */

        virtual TInt SetChannelCount( TInt aChannelCount );

        /**

        * Set number of AMR frame blocks included in one RTP packet.

        * Each frame block contains frames for all audio channels.

        * @since    Series-60 2.1

        * @param    aFrameblockCount - [input] Number of AMR frame blocks included 

        * in one RTP packet

        * @return   KErrNone if successful; system wide error code otherwise

        */

        virtual TInt SetFrameBlockCount( TInt aFrameblockCount );

        /**

        * Set number of redundant frame blocks included in one RTP packet.

        * Each frame block contains frames for all audio channels.

        * @since    Series 60 3.0

        * @param    aRedBlockCount  Number of redundant AMR frame blocks to be

        * included in one RTP packet

        * @return   KErrNone if successful; system wide error code otherwise

        */

        virtual TInt SetRedFrameBlockCount( TInt aRedBlockCount );

        /**

        * Initialize frame encoder ( Stream Encoder ).

        * Information to initialize are obtained from iPayload, calculation 

        * using iChannelCount and iFrameBlockCount.

        * Initialization should be done whenever a payload is finished.

        * @since    Series-60 2.1

        * @param    None

        * @return   void

        */

        virtual void InitializeFrameEncoder( );

    protected: // Functions

        /**

        * Constructor.

        */

        CAmrPayloadEncoder( TBool aIsNb );

        /**

        * By default Symbian 2nd phase constructor is private.

        */

        void ConstructL( );

        /**

        * Encode the AMR payload ( for one RTP packet ) into a given buffer.

        * Values to encode are obtained from `iFrames' array.

        * @since    Series-60 2.1

        * @param    aBuffer - [output] Buffer to store encoded data

        * @return   Total number of bytes encoded in the buffer

        */

        TInt Encode( TUint8* aBuffer );

        /**

        * Encode 'Table of Contents' into a given buffer at the given position.

        * Information to encode are obtained from `iFrames' array.

        * Byte and bit positions are updated after encoding is done.

        * @since Series-60 2.1

        * @param aBuffer - [output] Buffer to store encoded data.

        * @param aByteIndex - [input] Starting byte index ( starts from zero ).

        *                     [output] Byte index updated after encoding.

        * @param aBitIndex - [input] Starting bit index ( starts from zero ).

        *                    [output] Bit index updated after encoding.

        * @return void

        */

        void EncodeTableOfContents( TUint8* aBuffer, 

                                    TInt& aByteIndex, 

                                    TInt& aBitIndex );

        /**

        * Rips off unwanted NO_DATA frames from payload according to

        * RFC3267: 4.3.2.

        *

        * @since    Series 60 3.0

        * @param    None

        * @return   Number of frames discarded from a payload

        */

        virtual TInt DiscardExtraNoDataFrames();

        /**

        * Saves frame so it can be sent as redundancy later.

        *

        * @since    Series 60 3.0

        * @param    aFrameData      Frame data to save

        * @return   void

        */

        virtual void SaveRedundantFrame( const TDes8& aFrameData );

    protected:  // From CAmrPayloadFormatter

        /**

        * Initializes encoder. Encoder should be initialized when starting

        * playing.

        *

        * @since    Series 60 3.0

        * @param    None

        * @return   void

        */

        virtual void DoInitialize();

    protected: // Data

        // Encoder for payload header

        CAmrPayloadHeader* iHeaderEncoder;

        // Encoder for TOC entry

        CAmrTocEntry* iTocEntryEncoder;

        // Encoder for frame data

        TStreamEncoder iFrameEncoder;

        // Total speech bits in current payload

        TInt iTotalSpeechBits;

        // Number of redundant frames to be sent

        TInt iRedCount;

        // Indicates is redundancy count of sent frames collected

        TBool iRedIntervalCollected;

        // Indicates how many NO_DATA frames is discarded at this round

        TInt iFramesDiscarded;

    private:

        #ifdef TEST_EUNIT

            friend class UT_CAmrPayloadEncoder;

            friend class UT_CAmrPayloadFormatWrite;

        #endif	

    };

#endif  // __AMRPAYLOADENCODER_H