/*

   Copyright (C) 2003 Commonwealth Scientific and Industrial Research

   Organisation (CSIRO) Australia

   Redistribution and use in source and binary forms, with or without

   modification, are permitted provided that the following conditions

   are met:

   - Redistributions of source code must retain the above copyright

   notice, this list of conditions and the following disclaimer.

   - Redistributions in binary form must reproduce the above copyright

   notice, this list of conditions and the following disclaimer in the

   documentation and/or other materials provided with the distribution.

   - Neither the name of CSIRO Australia nor the names of its

   contributors may be used to endorse or promote products derived from

   this software without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A

   PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE ORGANISATION OR

   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

#include "config.h"

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "oggz/oggz.h"

#include "oggz_tools.h"

/* #define DEBUG */

typedef struct {

  ogg_int64_t delta;

  int nr_packets;

} OBTrackData;

typedef struct {

  ogg_int64_t base_units;

  OggzTable * tracks;

} OBData;

static  ogg_int64_t

_le_64 (ogg_int64_t l)

{

  ogg_int64_t ret=l;

  unsigned char *ucptr = (unsigned char *)&ret;

#ifdef WORDS_BIGENDIAN

  unsigned char temp;

  temp = ucptr [0] ;

  ucptr [0] = ucptr [7] ;

  ucptr [7] = temp ;

  temp = ucptr [1] ;

  ucptr [1] = ucptr [6] ;

  ucptr [6] = temp ;

  temp = ucptr [2] ;

  ucptr [2] = ucptr [5] ;

  ucptr [5] = temp ;

  temp = ucptr [3] ;

  ucptr [3] = ucptr [4] ;

  ucptr [4] = temp ;

#endif

  return (*(ogg_int64_t *)ucptr);

}

#define INT64_LE_AT(x) _le_64((*(ogg_int64_t *)(x)))

/********** OBTrackData **********/

static OBTrackData *

or_track_data_new (void)

{

  OBTrackData * ort;

  ort = malloc (sizeof (OBTrackData));

  if (ort == NULL) return NULL;

  ort->delta = -1;

  ort->nr_packets = 0;

  return ort;

}

static void

or_track_data_delete (OBTrackData * ort)

{

  free (ort);

}

/********** OBData **********/

static OBData *

or_data_new (void)

{

  OBData * ord;

  ord = malloc (sizeof (OBData));

  if (ord == NULL) return NULL;

  ord->base_units = -1;

  ord->tracks = oggz_table_new ();

  if (ord->tracks == NULL) {

    free (ord);

    return NULL;

  }

  return ord;

}

static void

or_data_delete (OBData * ord)

{

  int i, n;

  OBTrackData * ort;

  n = oggz_table_size (ord->tracks);

  for (i=0; i

    ort = oggz_table_nth (ord->tracks, i, NULL);

    or_track_data_delete (ort);

  }

  oggz_table_delete (ord->tracks);

}

/********** checked_fwrite **********/

static void

checked_fwrite (const void *data, size_t size, size_t count, FILE *stream)

{

  int n = fwrite (data, size, count, stream);

  if ((size_t)n != count) {

    perror ("write failed");

    exit (1);

  }

}

/********** Filter **********/

static int

filter_page (OGGZ * oggz, const ogg_page * og, long serialno, OBData * ord)

{

  OBTrackData * ort;

  ogg_int64_t granulepos, new_granulepos;

  ogg_int64_t iframe, pframe;

  int granuleshift;

  ort = oggz_table_lookup (ord->tracks, serialno);

  granulepos = ogg_page_granulepos ((ogg_page *)og);

  granuleshift = oggz_get_granuleshift (oggz, serialno);

  iframe = granulepos >> granuleshift;

  pframe = granulepos - (iframe << granuleshift);

  iframe -= ort->delta;

  new_granulepos = (iframe << granuleshift) + pframe;

#ifdef DEBUG

    fprintf (stderr, "old gp %lld, new gp %lld", granulepos, new_granulepos);

#endif

  *(ogg_int64_t *)(&og->header[6]) = _le_64(new_granulepos);

#ifdef DEBUG

  fprintf (stderr, ", totally new gp %lld\n", INT64_LE_AT(&og->header[6]));

#endif

  /* AFTER making any changes to the page, recalculate the page checksum */

  ogg_page_checksum_set ((ogg_page *)og);

  return 0;

}

static int

read_page (OGGZ * oggz, const ogg_page * og, long serialno, void * user_data)

{

  OBData * ord = (OBData *)user_data;

  OBTrackData * ort;

  ogg_int64_t gr_n, gr_d;

  int numheaders;

  if (ogg_page_bos ((ogg_page *)og)) {

    if ((ort = or_track_data_new ()) == NULL)

      return OGGZ_STOP_ERR;

    oggz_table_insert (ord->tracks, serialno, ort);

  } else {

    ort = oggz_table_lookup (ord->tracks, serialno);

  }

#ifdef DEBUG

  fprintf (stderr, "--------\n");

#endif

  numheaders = oggz_stream_get_numheaders (oggz, serialno);

  /* If this is the first data page of any track, use its timestamp

   * as the delta by which to shift all tracks. Hence this page will

   * get shifted to timestamp 0, and all other pages in the stream will

   * be shifted relatively.

   */

  if (ord->base_units == -1 && ort->nr_packets >= numheaders) {

    ord->base_units = oggz_tell_units (oggz);

#ifdef DEBUG

    fprintf (stderr, "BASE UNITS: %lld\n", ord->base_units);

#endif

  }

  /* If this is the first data page of a track, calculate the delta

   * by which to shift all pages of this track */

  if (ord->base_units != -1 && ort->nr_packets >= numheaders && ort->delta == -1) {

    oggz_get_granulerate (oggz, serialno, &gr_n, &gr_d);

    ort->delta = (ord->base_units * gr_n) / (gr_d);

#ifdef DEBUG

    fprintf (stderr, "%010lu: DELTA %lld (gr: %lld/%lld)\n",

	     serialno, ort->delta, gr_n, gr_d);

#endif

  }

  /* header pages have a granulepos 0 and should not have it changed */

  if (ogg_page_granulepos ((ogg_page *) og) != 0) {

    filter_page (oggz, og, serialno, ord);

  }

  ort->nr_packets += ogg_page_packets ((ogg_page *)og);

#ifdef DEBUG

  fprintf (stderr, "%010lu: %d packets, gp %lld\n",

	   serialno, ort->nr_packets, ogg_page_granulepos ((ogg_page *)og));

#endif

  checked_fwrite (og->header, 1, og->header_len, stdout);

  checked_fwrite (og->body, 1, og->body_len, stdout);

  return 0;

}

int

usage (char * progname)

{

  printf ("usage: %s filename\n", progname);

  printf ("Shift timestamps on all pages such that the stream starts at 0.\n");

  return 0;

}

int

main (int argc, char ** argv)

{

  char * progname = argv[0];

  OGGZ * oggz;

  OBData * ord;

  int ret;

  if (argc < 2) {

    usage (progname);

    return (1);

  }

  if (!strncmp (argv[1], "-?", 2)) {

    printf ("-h --help\n");

    exit (0);

  }

  if (!strcmp (argv[1], "-h") || !strcmp (argv[1], "--help")) {

    usage (progname);

    return (0);

  }

  ord = or_data_new ();

  if (ord == NULL) goto oom;

  if ((oggz = oggz_open ((char *)argv[1], OGGZ_READ | OGGZ_AUTO)) == NULL) {

    printf ("unable to open file %s\n", argv[1]);

    exit (1);

  }

  oggz_set_read_page (oggz, -1, read_page, ord);

  ret = oggz_run (oggz);

  oggz_close (oggz);

  or_data_delete (ord);

  if (ret == OGGZ_ERR_STOP_ERR) goto oom;

  exit (0);

oom:

  fprintf (stderr, "%s: out of memory\n", progname);

  exit (1);

}