//-------------------------------------------------------------------------
//  This class encapsulates a flac stream.  Only the functions
//  needed by the alsaplayer flac plugin are implemented.
//
//  Copyright (c) 2002 by Drew Hess <dhess@bothan.net>
//
/*  This file is part of AlsaPlayer.
 *
 *  AlsaPlayer is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  AlsaPlayer is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
 */
//-------------------------------------------------------------------------


#ifndef _FLAC_STREAM_H_
#define _FLAC_STREAM_H_

#if !defined(FLAC_API_VERSION_CURRENT) || FLAC_API_VERSION_CURRENT < 8
#define LEGACY_FLAC
#else
#undef LEGACY_FLAC
#endif

#include <string>
#include "reader.h"

extern "C"
{
#include <FLAC/stream_decoder.h>
}

#undef DEBUG

namespace Flac
{

class FlacEngine;
class FlacTag;

class FlacStream
{
 public:

    //--------------------------------------------------------------
    // Return true if we think name points to  a valid flac stream.
    //--------------------------------------------------------------

    static bool isFlacStream (const std::string & name);


 public:

    //---------------------------------------------------------------
    // Constructor & destructor.  The reader_type f belongs to the
    // FlacStream after construction, and it will be closed
    // upon deletion of the FlacStream object.  If reportErrors is
    // false, the object will squelch all alsaplayer_error messages.
    // This is particularly useful when attempting to open streams
    // to determine whether they're FLAC streams.
    //---------------------------------------------------------------

    FlacStream (const std::string & name,
		reader_type * f,
		bool reportErrors = true);

    virtual ~FlacStream ();


    //------------------------------------------------------------------
    // Initialize the stream decoder, installing all callbacks from the
    // engine.  Returns false if the decoder could not be initialized
    // or if the engine hasn't been set (see setEngine).
    //------------------------------------------------------------------

    virtual bool        open ();


    //----------------------------------------------------------
    // Get a pointer to the FlacEngine for this stream decoder.
    //----------------------------------------------------------

    FlacEngine *        engine () const;


    //----------------------------------------------------------------------
    // Get a pointer to the FlacTag for this stream, or 0 if there is none.
    //----------------------------------------------------------------------

    FlacTag *           tag () const;


    //----------------------------------
    // Set the FlacTag for this stream.
    //----------------------------------

    void                setTag (FlacTag * tag);


    //-----------------------------------
    // Get the name of the flac stream.
    //-----------------------------------

    const std::string & name () const;


    //------------------------------------------------------
    // Get the sample rate of the uncompressed audio stream.
    //------------------------------------------------------

    unsigned int                sampleRate () const;


    //----------------------------------------
    // Number of channels in the audio stream.
    //----------------------------------------

    unsigned int                channels () const;


    //----------------------------------------------------------
    // Total number of uncompressed samples in the audio stream.
    //----------------------------------------------------------

    FLAC__uint64                totalSamples () const;


    //--------------------------------------------------------------
    // The number of uncompressd samples in one block of audio data.
    //--------------------------------------------------------------

    unsigned int                samplesPerBlock () const;


    //-----------------
    // Bits per sample.
    //-----------------

    unsigned int                bps () const;


    //----------------------------------------------------------------
    // Process the next flac block in the stream.  This has the side-
    // effect of calling the write callback if there is data to fetch
    // in the stream.
    //
    // Returns false if there's no more data in the stream, or if
    // there's an error in the stream decoder.
    //----------------------------------------------------------------

    virtual bool                processOneBlock ();


    //-------------------------------------------------------------------
    // Seeks are unsupported.  Returns false.
    //-------------------------------------------------------------------

    virtual bool                seekAbsolute (FLAC__uint64);


 protected:

    void                        apError (const char * msg);
    void                        apError (const char * fmt, const char * str);

 protected:

    FlacStream ();


    //---------------------------------------------------------------------
    // The following 3 functions do all the real work for the
    // various callbacks and are shared by all FLAC stream implementations.
    //---------------------------------------------------------------------

    void         realMetaCallBack (const FLAC__StreamMetadata * md);

    void         realErrCallBack (const char * name,
				  FLAC__StreamDecoderErrorStatus status);

    FLAC__StreamDecoderWriteStatus
                 realWriteCallBack (const FLAC__Frame * block,
				    const FLAC__int32 * const buffer[]);


    //------------------------------------------------------------
    // Does all the real work for read callbacks for non-seekable
    // streams.
    //------------------------------------------------------------

    FLAC__StreamDecoderReadStatus
                 realReadCallBack (FLAC__byte buffer[],
				   size_t * bytes);


 protected:

    FlacEngine *  _engine;
    bool          _mcbSuccess;
    reader_type * _datasource;
    bool          _reportErrors;

    //---------------------------------------------------------------------
    // Stream info.  "Samples" always refers to uncompressed audio samples.
    //---------------------------------------------------------------------

    unsigned int  _channels;      // number of channels in the stream
    unsigned int  _bps;           // bits per sample
    unsigned int  _sampleRate;    // number of samples per channel per sec
    unsigned int  _sampPerBlock;  // number of samples per block of data
    FLAC__uint64  _totalSamp;     // total number of samples in the stream


 private:

    //-----------------------------------------------------------------
    // The flac metadata callback.  It's called as a side effect of the
    // open method.  It'll be called once for each metadata block in
    // the flac stream.  To check its success, look at _mcbSuccess.
    //-----------------------------------------------------------------

    static void metaCallBack (const FLAC__StreamDecoder * decoder,
			      const FLAC__StreamMetadata * md,
			      void * cilent_data);

    static FLAC__StreamDecoderWriteStatus
	writeCallBack (const FLAC__StreamDecoder * decoder,
		       const FLAC__Frame * block,
		       const FLAC__int32 * const buffer[],
		       void * client_data);

    static FLAC__StreamDecoderReadStatus
	readCallBack (const FLAC__StreamDecoder * decoder,
		      FLAC__byte buffer[],
		      size_t * bytes,
		      void * client_data);

    static void errCallBack (const FLAC__StreamDecoder * decoder,
			     FLAC__StreamDecoderErrorStatus status,
			     void * client_data);


 private:

    FLAC__StreamDecoder * _decoder;
    FlacTag *             _tag;
    const std::string     _name;


}; // class FlacStream


//----------------
// Inline methods.
//----------------

inline FlacTag *
FlacStream::tag () const
{
    return _tag;
}

inline FlacEngine *
FlacStream::engine () const
{
    return _engine;
}

inline void
FlacStream::setTag (FlacTag * tag_)
{
    _tag = tag_;
}

inline const std::string &
FlacStream::name () const
{
    return _name;
}

inline unsigned int
FlacStream::sampleRate () const
{
    return _sampleRate;
}

inline FLAC__uint64
FlacStream::totalSamples () const
{
    return _totalSamp;
}

inline unsigned int
FlacStream::samplesPerBlock () const
{
    return _sampPerBlock;
}

inline unsigned int
FlacStream::bps () const
{
    return _bps;
}

inline unsigned int
FlacStream::channels () const
{
    return _channels;
}

inline bool
FlacStream::seekAbsolute (FLAC__uint64)
{
    return false;
}

} // namespace Flac

#endif // _FLAC_STREAM_H_