/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2002 Björn Stenberg
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/

#include "codec.h"

#include <codecs/libFLAC/include/FLAC/seekable_stream_decoder.h>
#include "playback.h"
#include "lib/codeclib.h"
#include "dsp.h"

#define FLAC_MAX_SUPPORTED_BLOCKSIZE 4608
#define FLAC_MAX_SUPPORTED_CHANNELS  2

static struct codec_api* rb;
static uint32_t samplesdone;

/* Called when the FLAC decoder needs some FLAC data to decode */
FLAC__SeekableStreamDecoderReadStatus flac_read_handler(const FLAC__SeekableStreamDecoder *dec, 
                                                        FLAC__byte buffer[], unsigned *bytes, void *data)
{   struct codec_api* ci = (struct codec_api*)data;
    (void)dec;

    *bytes=(unsigned)(ci->read_filebuf(buffer,*bytes));

    if (*bytes==0) {
      return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
    } else {
      return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
    }
}

static unsigned char pcmbuf[FLAC_MAX_SUPPORTED_BLOCKSIZE*FLAC_MAX_SUPPORTED_CHANNELS*2] IDATA_ATTR;

/* Called when the FLAC decoder has some decoded PCM data to write */
FLAC__StreamDecoderWriteStatus flac_write_handler(const FLAC__SeekableStreamDecoder *dec, 
  					          const FLAC__Frame *frame, 
					          const FLAC__int32 * const buf[], 
					          void *data)
{
   struct codec_api* ci = (struct codec_api*)data;
   (void)dec;
   unsigned int c_samp, c_chan, d_samp;
   uint32_t data_size = frame->header.blocksize * frame->header.channels * 2; /* Assume 16-bit words */
   uint32_t samples = frame->header.blocksize;
   int yieldcounter = 0;


   if (samples*frame->header.channels > (FLAC_MAX_SUPPORTED_BLOCKSIZE*FLAC_MAX_SUPPORTED_CHANNELS)) {
     // ERROR!!!
     DEBUGF("ERROR: samples*frame->header.channels=%d\n",samples*frame->header.channels);
     return(FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE);
   }

   (void)dec;
   for(c_samp = d_samp = 0; c_samp < samples; c_samp++) {
     for(c_chan = 0; c_chan < frame->header.channels; c_chan++, d_samp++) {
       pcmbuf[d_samp*2] = (buf[c_chan][c_samp]&0xff00)>>8;
       pcmbuf[(d_samp*2)+1] = buf[c_chan][c_samp]&0xff;
       if (yieldcounter++ == 100) {
         rb->yield();
         yieldcounter = 0;
       }
     }
   } 

   samplesdone+=samples;
   ci->set_elapsed(samplesdone/(ci->id3->frequency/1000));
   
   rb->yield();
   while (!ci->audiobuffer_insert(pcmbuf, data_size))
     rb->yield();

   return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}

void flac_metadata_handler(const FLAC__SeekableStreamDecoder *dec, 
                           const FLAC__StreamMetadata *meta, void *data)
{
  /* Ignore metadata for now... */
  (void)dec;
  (void)meta;
  (void)data;
}


void flac_error_handler(const FLAC__SeekableStreamDecoder *dec, 
                        FLAC__StreamDecoderErrorStatus status, void *data)
{
    (void)dec;
    (void)status;
    (void)data;
}

FLAC__SeekableStreamDecoderSeekStatus flac_seek_handler (const FLAC__SeekableStreamDecoder *decoder, 
                                                         FLAC__uint64 absolute_byte_offset,
                                                         void *client_data)
{
  (void)decoder;
  struct codec_api* ci = (struct codec_api*)client_data;

  if (ci->seek_buffer(absolute_byte_offset)) {
    return(FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK);
  } else {
    return(FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_ERROR);
  }
}

FLAC__SeekableStreamDecoderTellStatus flac_tell_handler (const FLAC__SeekableStreamDecoder *decoder, 
                                                         FLAC__uint64 *absolute_byte_offset, void *client_data)
{ 
  struct codec_api* ci = (struct codec_api*)client_data;

  (void)decoder;
  *absolute_byte_offset=ci->curpos;
  return(FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK);
}

FLAC__SeekableStreamDecoderLengthStatus flac_length_handler (const FLAC__SeekableStreamDecoder *decoder, 
                                                         FLAC__uint64 *stream_length, void *client_data)
{
  struct codec_api* ci = (struct codec_api*)client_data;

  (void)decoder;
  *stream_length=ci->filesize;
  return(FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_OK);
}

FLAC__bool flac_eof_handler (const FLAC__SeekableStreamDecoder *decoder, 
                             void *client_data)
{
  struct codec_api* ci = (struct codec_api*)client_data;

  (void)decoder;
  if (ci->curpos >= ci->filesize) {
    return(true);
  } else {
    return(false);
  }
}

#ifndef SIMULATOR
extern char iramcopy[];
extern char iramstart[];
extern char iramend[];
#endif

/* this is the codec entry point */
enum codec_status codec_start(struct codec_api* api)
{
    struct codec_api* ci = api;
    FLAC__SeekableStreamDecoder* flacDecoder;

  /* Generic codec initialisation */
  TEST_CODEC_API(api);

  /* if you are using a global api pointer, don't forget to copy it!
     otherwise you will get lovely "I04: IllInstr" errors... :-) */
  rb = api;

#ifndef SIMULATOR
  rb->memcpy(iramstart, iramcopy, iramend-iramstart);
#endif

  ci->configure(CODEC_SET_FILEBUF_LIMIT, (int *)(1024*1024*10));
  ci->configure(CODEC_SET_FILEBUF_WATERMARK, (int *)(1024*512));
  ci->configure(CODEC_SET_FILEBUF_CHUNKSIZE, (int *)(1024*128));

  ci->configure(DSP_DITHER, (bool *)false);
  ci->configure(DSP_SET_STEREO_MODE, (int *)STEREO_INTERLEAVED);
  ci->configure(DSP_SET_SAMPLE_DEPTH, (int *)(16));
  
  next_track:

  if (codec_init(api)) {
    return CODEC_ERROR;
  }

  while (!rb->taginfo_ready)
      rb->yield();
    
  if (rb->id3->frequency != NATIVE_FREQUENCY) {
      rb->configure(DSP_SET_FREQUENCY, (long *)(rb->id3->frequency));
      rb->configure(CODEC_DSP_ENABLE, (bool *)true);
  } else {
      rb->configure(CODEC_DSP_ENABLE, (bool *)false);
  }
  
  /* Create a decoder instance */

  flacDecoder=FLAC__seekable_stream_decoder_new();

  /* Set up the decoder and the callback functions - this must be done before init */

  /* The following are required for stream_decoder and higher */
  FLAC__seekable_stream_decoder_set_client_data(flacDecoder,ci);
  FLAC__seekable_stream_decoder_set_write_callback(flacDecoder, flac_write_handler);
  FLAC__seekable_stream_decoder_set_read_callback(flacDecoder, flac_read_handler);
  FLAC__seekable_stream_decoder_set_metadata_callback(flacDecoder, flac_metadata_handler);
  FLAC__seekable_stream_decoder_set_error_callback(flacDecoder, flac_error_handler);
  FLAC__seekable_stream_decoder_set_metadata_respond(flacDecoder, FLAC__METADATA_TYPE_STREAMINFO);

  /* The following are only for the seekable_stream_decoder */
  FLAC__seekable_stream_decoder_set_seek_callback(flacDecoder, flac_seek_handler);
  FLAC__seekable_stream_decoder_set_tell_callback(flacDecoder, flac_tell_handler);
  FLAC__seekable_stream_decoder_set_length_callback(flacDecoder, flac_length_handler);
  FLAC__seekable_stream_decoder_set_eof_callback(flacDecoder, flac_eof_handler);


  /* QUESTION: What do we do when the init fails? */
  if (FLAC__seekable_stream_decoder_init(flacDecoder)) {
    return CODEC_ERROR;
  }

  /* The first thing to do is to parse the metadata */
  FLAC__seekable_stream_decoder_process_until_end_of_metadata(flacDecoder);

  samplesdone=0;
  ci->set_elapsed(0);
  /* The main decoder loop */
  while (FLAC__seekable_stream_decoder_get_state(flacDecoder)!=FLAC__SEEKABLE_STREAM_DECODER_END_OF_STREAM) {
    rb->yield();
    if (ci->stop_codec || ci->reload_codec) {
      break;
    }

    if (ci->seek_time) {
        int sample_loc;

        sample_loc = ci->seek_time/1000 * ci->id3->frequency;
        if (FLAC__seekable_stream_decoder_seek_absolute(flacDecoder,sample_loc)) {
          samplesdone=sample_loc;
          ci->set_elapsed(samplesdone/(ci->id3->frequency/1000));
        }
        ci->seek_time = 0;
    }

    FLAC__seekable_stream_decoder_process_single(flacDecoder);
  }

  /* Flush the libFLAC buffers */
  FLAC__seekable_stream_decoder_finish(flacDecoder);

  if (ci->request_next_track())
    goto next_track;

  return CODEC_OK;
}