// Copyright (c) 2001-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members

// which accompanies this distribution, and is available

// at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

//

#ifndef __MMF_SERVER_FORMAT_H__

#define __MMF_SERVER_FORMAT_H__

#include <mmf/server/mmfdatasink.h>

#include <mmf/server/mmfdatasource.h>

#include <ecom/ecom.h>

#include <mmfplugininterfaceuids.hrh>

const TUint KMMFFormatDefaultFrameSize = 0x1000;  //4K

/**

@publishedAll

@released

Base class from which source formats can be derived from. The intended usage is for controllers that can support more

than one type of format. The class is an MDataSource as far as the data path is concerned but is an MDataSink to the clip

that is the source of the actual data.

All CMMFFormatDecode plugin DLLs must include interface_uid = KMmfUidPluginInterfaceFormatDecode in their .rss files.

*/

class CMMFFormatDecode : public CBase, public MDataSource, public MDataSink

	{

public:

	// ECOM creation.

	IMPORT_C static CMMFFormatDecode* NewL( TUid aUid, MDataSource* aSource );

	IMPORT_C static CMMFFormatDecode* NewL( const TDesC& aFileName, MDataSource* aSource, const TDesC& aPreferredSupplier ) ;

	IMPORT_C static CMMFFormatDecode* NewL( const TDesC8& aSourceHeader,  MDataSource* aSource, const TDesC& aPreferredSupplier ) ;

	IMPORT_C static CMMFFormatDecode* NewL( MDataSource* aSource, const TDesC& aPreferredSupplier ) ;

	IMPORT_C static CMMFFormatDecode* NewL( const TDesC& aFileName, MDataSource* aSource, const TDesC& aPreferredSupplier, TBool& aSupportsCustomInterfaces ) ;

	IMPORT_C static CMMFFormatDecode* NewL( const TDesC8& aSourceHeader,  MDataSource* aSource, const TDesC& aPreferredSupplier, TBool& aSupportsCustomInterfaces ) ;

	IMPORT_C static CMMFFormatDecode* NewL( MDataSource* aSource, const TDesC& aPreferredSupplier, TBool& aSupportsCustomInterfaces ) ;

	/**

	Destructor.

	*/

	virtual ~CMMFFormatDecode()  {REComSession::DestroyedImplementation(iDtor_ID_Key);};

	/**

	Returns the ECom plugin UID of this format.

	@return The plugin UID.

	*/

	TUid ImplementationUid() const {return iImplementationUid;}

	/**

	Gets the number of streams of the specified media type.

	This is a virtual function that each derived class must implement.

	@param  aMediaType

	        The UID of the media type, for example KUidMediaTypeAudio or KUidMediaTypeVideo.

	@return	The number of streams of multimedia data in the format for the specified media type.

	        For example, for a WAV or mp3 audio file this procedure would return 1 for a media

	        type of audio and 0 for a media type of video. More complex multimedia formats (for

	        example AVI and mp4) can support multiple streams of both video and audio.

	*/

	virtual TUint Streams(TUid aMediaType) const = 0;

	/**

	Returns the time interval for one frame for the specified media type.

	This is a virtual function that each derived class must implement.

	In the case of video, a frame would usually be one frame of video. In the case of

	audio, a frame may correspond to a frame of audio, if the particular audio data type

	is framed eg mp3. There are two definitions of a frame. A format frame, which may

	consist of several frames of a particular framed audio data type. This may be the case,

	for example for GSM610 (a low quality audio data type used in telephony) where a frame

	is only 65 bytes large. In this case a format frame consists of several GSM610 data type

	frames as passing the data out 65 bytes at a time would be inefficient. In the case of

	non-framed data such as pcm, a frame can be an arbitrary size determined by the format plugin.

	@param  aMediaType

	        The media type id.

	@return	The frame time interval

	*/

	virtual TTimeIntervalMicroSeconds FrameTimeInterval(TMediaId aMediaType) const = 0;

	/**

	Returns the duration of the clip for the specified media type.

	This is a virtual function that each derived class must implement.

	@param  aMediaType

	        The media type ID.

	@return The duration of the clip.

	*/

	virtual TTimeIntervalMicroSeconds Duration(TMediaId aMediaType) const = 0;

	/**

	Request from CMMFDataPath to fill the specified buffer.

	The CMMFFormat needs to break this down into one or more reads from the clip

	(from MDataSource - CMMFFormatDecode is a MDataSource to a CMMFDataPath consumer).

	This is a virtual function that each derived class must implement.

	This method is the means by which data is obtained from the data source. aBuffer is

	the buffer that needs filling from the source data stream as identified by aMediaId. The

	format should read the frame number of the buffer via the buffer's CMMFBuffer::FrameNumber()

	method. From this the format should be able to determine the actual position of the data on

	the data source. The technique here depends on the nature of the format. For a linear audio

	format, the position can be obtained by a simple calculation of the frame size, the header size

	and where appropriate the datatype.

	For non-linear formats either an index table of frame number and location will need to be

	created in the NewL() or some form of approximating algorithm will be required. Some formats have

	an index table as part of the format e.g. AVI. If no random access is required then no index table

	is required, the format can keep track of the current read position and increment it on each access,

	and reset it if the frame number is reset to 0 or 1. Given that for non-linear i.e. variable bit rate

	formats, the size of the data read may vary from frame to frame, then the format should either set

	the request size of the buffer for the required frame or call the source's ReadBufferL() (either

	CMMFClip::ReadBufferL(), CMMFDescriptor ::ReadBufferL() or CMMFFile::ReadBufferL()) function that

	takes the aLength parameter.

	It is the responsibility of the format decode to determine the size and position of the source data

	for each frame. For linear audio formats, the format decode should fill the buffer up to its maximum

	length. For multimedia formats e.g. mp4, AVI etc, the format decode is effectively acting as a demultiplexor,

	and must obtain the appropriate data from the source depending on the aMediaId.

	@param  aBuffer

	        The buffer to fill.

	@param  aConsumer

	        The consumer.

	@param  aMediaId

	        The media type ID.

	*/

	virtual void FillBufferL(CMMFBuffer* aBuffer, MDataSink* aConsumer, TMediaId aMediaId)=0;

	/**

	@internalAll

	Indicates data has been added to the file.

	@param  aBuffer

	        The emptied buffer.

    */

	inline virtual void BufferEmptiedL(CMMFBuffer* aBuffer);

	/**

	Tests whether a source buffer can be created.

	The format knows what type of source buffer it requires so default returns ETrue.

	It doesn't usually need to set the size of this buffer.

	@return	A boolean indicating whether a buffer can be created. ETrue if the buffer can be created,

	        EFalse otherwise.

	*/

	virtual TBool CanCreateSourceBuffer() {return ETrue;}

	/**

	Creates a source buffer.

	This is a virtual function that each derived class must implement.

	This function should create a buffer of length 0, the maximum length should be equal to the maximum

	possible frame size. In the case of non framed data it should be set to an arbitrary size, which is

	effectively a trade off between being too small which will affect performance as more source reads

	are required, and being too large which will give very coarse positioning granularity. For pcm data,

	a buffer size of 4K is a good compromise. The same compromise also applies when deciding to put multiple

	audio frames into one format frame. The sink buffer size may also effect the format buffer size and

	the controller may use this to suggest a buffer size to the format by calling the format's SuggestSourceBufferSize()

	method. Alternatively the MDataSource::CreateSourceBufferL() function that takes the additional aSinkBuffer

	parameter may also be used when deciding the source buffer maximum size of the created source buffer.

	@param  aMediaId

	        The media type ID.

	@param  aReference

	        If ETrue the MDataSource owns the buffer. If EFalse, then the caller owns the buffer. This

	        should normally be set to EFalse as format plugins do not create the reference buffer.

	@return The created source buffer.

	*/

	virtual CMMFBuffer* CreateSourceBufferL(TMediaId aMediaId, TBool &aReference)=0;

	/**

	Returns the source data type code for the specified media type ID.

	Used by the CMMFDataPath for codec matching.

	This is a virtual function that each derived class must implement.

	@param  aMediaId

	        The media type ID.

	@return The source data type code.

	*/

	virtual TFourCC SourceDataTypeCode(TMediaId aMediaId)=0;

	/**

	@internalAll

    Adds a buffer to a clip.

	@param  aBuffer

	        The buffer to which the clip is added.

	@param  aSupplier

	        The data source.

	@param  aMediaId

	        The Media ID.

	*/

	inline virtual void EmptyBufferL(CMMFBuffer* aBuffer, MDataSource* aSupplier, TMediaId aMediaId);

	/**

	Indicates the data source has filled the buffer.

	Called by the CMMFFormat's MDataSource when it has filled the buffer.

	The default implementation below would need overriding in cases where multiple

	clip reads were required to fill the buffer from the data path.

	@param  aBuffer

	        The buffer to which the clip is added.

	*/

	virtual void BufferFilledL(CMMFBuffer* aBuffer) {iDataPath->BufferFilledL(aBuffer);}

	/**

	Tests whether a sink buffer can be created.

	Format would normally pass its own buffer onto the CMMFClip, so

	this may not be required. The default returns EFalse.

	@return A boolean indicating if the sink buffer can be created. ETrue if buffer can be created, EFalse otherwise.

	*/

	virtual TBool CanCreateSinkBuffer() {return EFalse;}

	/**

	Creates a sink buffer for the specified media ID. The default version returns NULL.

	@param  aMediaId

	        The media type ID.

	@param  aReference

	        If ETrue the MDataSink owns the buffer.

	        If EFalse, then the caller owns the buffer.

	@return The CMMFBuffer sink buffer.

	*/

	inline virtual CMMFBuffer* CreateSinkBufferL(TMediaId aMediaId, TBool &aReference);

	/**

	Returns the sink data type code for the specified media type ID.

	This would be the same as the source data type four CC although

	the clip is not going to need this info.

	@param  aMediaId

	        The media type id.

	@return The sink data type code.

	*/

	inline virtual TFourCC SinkDataTypeCode(TMediaId aMediaId);

	/**

	Gets the number of meta data entries.

	Meta Data support. The decode format is only capable of reading meta data entries from the clip.

	This is an optional method, used to return the number of meta data entries present in the format.

	A meta data entry is a format-specific field such as authorship, copyright, security details etc.

	The function is optional as many formats do not provide support for such additional meta data fields.

	The default leaves with KErrNotSupported.

	@param  aNumberOfEntries

	        A reference to the number of meta data entries supported by the format. On return, contains

	        the number of meta data entries.

	*/

	inline virtual void GetNumberOfMetaDataEntriesL(TInt& aNumberOfEntries);

	/**

	Returns the specified meta data entry.

	This method is optional as many formats do not provide support for such additional meta data fields.

	The default leaves with KErrNotSupported.

	@param  aIndex

	        The zero based meta data entry index to retrieve.

	@return The meta data entry.

	*/

	inline virtual CMMFMetaDataEntry* MetaDataEntryL(TInt aIndex);

	//audio format methods

	/**

	Sets the number of channels.

	The default returns KErrNotSupported.

	There would normally be no need to override this function as the format decode plugin can normally

	determine for itself the number of channels. It is only necessary to override this in cases where the

	format decode plugin cannot determine for itself the number of channels.  This function should not be

	used if the audio clip already exists; that is, in the "Open and Append" scenario, when the function's

	behaviour is undefined.

	@param  aChannels

	        The number of channels.

	@return An error code indicating if the function call was successful. KErrNone on success, otherwise

            another of the system-wide error codes.

	*/

	inline virtual TInt SetNumChannels(TUint aChannels);

	/**

	Sets the sample rate.

	The default implementation returns KErrNotSupported.

	There would normally be no need to override this function as the format decode can normally determine

	the sample rate for itself. It is only necessary to override this in cases where the format decode plugin

	cannot determine for itself the sample rate.

	@param  aSampleRate

	        The sample rate.

	@return An error code indicating if the function call was successful. KErrNone on success, otherwise

	        another of the system-wide error codes.

	*/

	inline virtual TInt SetSampleRate(TUint aSampleRate);

	/**

	Sets the bit rate.

	The default implementation returns KErrNotSupported.

	This method is mainly provided for variable bit rate formats, such as mp3, where the bit rate can

	not be directly calculated from the sample rate. There would normally be no need to override this

	function as the format decode can normally determine the sample rate for itself. It is only necessary

	to override this in cases where the format decode plugin cannot determine for itself the sample rate.

	@param aBitRate

	       The bit rate in bits per second.

	@return An error code indicating if the function call was successful. KErrNone on success, otherwise

	        another of the system-wide error codes.

	*/

	inline virtual TInt SetBitRate(TUint aBitRate);

	/**

	Returns the number of channels.

	The default implementation returns 0.

	@return	The number of channels.

	*/

	virtual TUint NumChannels() {return 0;}

	/**

	Gets the sample rate.

	The default implementation returns 0.

	@return The sample rate.

	*/

	virtual TUint SampleRate() {return 0;}

	/**

	Gets the bit rate.

	The default implementation returns 0.

	This method is mainly provided for variable bit rate formats, such as mp3, where the bit rate 

	can not be directly calculated from the sample rate. This function needs overriding for any format 

	decode that supports audio.

	@return The bit rate.

	*/

	virtual TUint BitRate() {return 0;}

	/**

	Gets the supported sample rates.

	The default implementation leaves with KErrNotSupported.

	This should return an array of sample rates supported by the format where applicable. Note 

	that this refers to the possible sample rates supported by the format, not the actual sample rate,

	which will be one of the supported sample rates. The implementation of this function is optional.

	@param  aSampleRates

	        Reference to an array of supported sample rates.

	*/

	inline virtual void GetSupportedSampleRatesL(RArray<TUint>& aSampleRates);

	/**

	Gets the supported bit rates.

	The default leaves with KErrNotSupported.

	This should return an array of bit rates supported by the format where applicable. Note that this

	refers to the possible bit rates supported by the format, not the actual bit rate, which will be

	one of the supported bit rates. The implementation of this function is optional.

	@param  aBitRates

	        Reference to an array of supported bit rates.

	*/

	inline virtual void GetSupportedBitRatesL(RArray<TUint>& aBitRates);

	/**

	Gets the supported number of channels.

	The default leaves with KErrNotSupported.

	The implementation of this procedure should return an array of channels supported by the format

	where applicable. Note that this refers to the possible number of channels supported by the format,

	not the actual number of channels, which will be one of the supported channels. For example, for a

	format decode plugin capable of supporting mono and stereo the procedure would return an array of

	length two the first array member containing the value 1 and the second containing the value 2. The

	implementation of this function is optional.

	@param  aNumChannels

	        A reference to an array of supported number of channels.

	*/

	inline virtual void GetSupportedNumChannelsL(RArray<TUint>& aNumChannels);

	/**

	Gets the supported data types for the given media type id.

	The default leaves with KErrNotSupported.

    The implementation of this procedure should return an array of data types supported by the format where

	applicable. Note that this refers to the possible data types that may be supported by the format, not the

	actual data type of the format, which will be one of the supported data types. For example, for a format

	decode plugin capable of supporting pcm16 and GSM610 the procedure would return an array of length two the

	first array member containing the fourCC code ' P16' and the second containing the value GSM6. The

	implementation of this function is optional.

	@param  aMediaId

	        The media type id.

	@param  aDataTypes

	        A reference to an array of supported data types.

	*/

	inline virtual void GetSupportedDataTypesL(TMediaId aMediaId, RArray<TFourCC>& aDataTypes);

	/**

	Used by the sink to suggest a source buffer size.

	This is an optional function provided so that a controller can suggest a buffer

	size for the format. The controller should not assume that the format will accept

	the suggested buffer size and there is no obligation on behalf of the format to

	use the suggested buffer size.

	@param  aSuggestedBufferSize

	        A recommended buffer size that the format should create.

	*/

	inline virtual void SuggestSourceBufferSize(TUint aSuggestedBufferSize);

	/**

	Used to set the format's position.

	Subsequent data reads should ignore the FrameNumber in the CMMFBuffer and use this

	setting to determine what data to provide.

	The actual position the format sets itself may vary from this setting to ensure

	that it is aligned to the sample boundaries ensuring consistent data output.

	If not supported, positional information should be extracted from the FrameNumber in CMMFBuffer

	@param  aPosition

	        The position the format should use.

	*/

    inline virtual void SetPositionL(const TTimeIntervalMicroSeconds& aPosition);

	/**

	Supplies the current position.

	Subsequent data reads will commence from this position.

	@return The current position in microseconds.

	*/

	virtual TTimeIntervalMicroSeconds PositionL() {User::Leave(KErrNotSupported);return TTimeIntervalMicroSeconds(0);}

protected:

	//ConstructSourceL should never be called. The CMMFFormatDecode NewL functions should

	//always be used to instantiate a CMMFFormatDecode object (not MDataSource::NewL)

	/**

	@internalAll

	*/

	virtual void ConstructSourceL( const TDesC8& /*aInitData*/ ) {User::Leave(KErrNotSupported);}

	//ConstructSinkL should never be called. The CMMFFormatDecode NewL functions should

	//always be used to instantiate a CMMFFormatDecode object (not MDataSink::NewL)

	/**

	@internalAll

	*/

	virtual void ConstructSinkL( const TDesC8& /*aInitData*/ ) {User::Leave(KErrNotSupported);}

	/**

	Default constructor

	*/

	CMMFFormatDecode() : MDataSource(KUidMmfFormatDecode), MDataSink(KUidMmfFormatDecode) {};

	// Creates and initialises format plugin.

	static CMMFFormatDecode* CreateFormatL(TUid aImplementationUid, MDataSource* aSource);

protected:

	/**

	The clip is the source for the decode format.

	*/

	MDataSource* iClip;

	/** 

	The data path is the sink for the decode format.

	*/

	MDataSink* iDataPath;

private:

	TUid iDtor_ID_Key; 			// do not move - referenced inline in ~CMMFFormatDecode()

	TUid iImplementationUid;	// do not move - referenced inline in ImplementationUid()

	};