/*
  dvdxchap -- utility for extracting chapter start times from
  IFO files

  Written by Moritz Bunkus <moritz@bunkus.org>

  Distributed under the GPL
  see the file COPYING for details
  or visit http://www.gnu.org/copyleft/gpl.html
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <inttypes.h>
#include <dvdread/dvd_reader.h>
#include <dvdread/ifo_read.h>
#include <dvdread/ifo_print.h>

void usage() {
  fprintf(stdout,
    "ogmtools v" VERSION "\n"
    "Usage: dvdxchap [options] DVD-SOURCE\n\n"
    " options:\n"
    "   -t, --title num            Use title 'num'. Default is 1.\n"
    "   -c, --chapter start[-end]  Chapter to start at (to end at). Default 1.\n"
    "   -v, --verbose              Increase verbosity\n"
    "   -V, --version              Show version information\n"
    "   -h, --help                 Show this help\n");
}

void display_chapters(char *source, int title, int start, int end, int verbose) {
  dvd_reader_t   *dvd;
  ifo_handle_t   *vmg;
  ifo_handle_t   *vts;
  tt_srpt_t      *tt_srpt;
  int             ttn, pgn, pgc_id, start_cell, end_cell, i, j;
  vts_ptt_srpt_t *vts_ptt_srpt;
  pgc_t          *cur_pgc;
  dvd_time_t     *dt;
  double          fps;
  long            hour, minute, second, ms, overall_time, start_time, cur_time;
  
  dvd = DVDOpen(source);
  if (dvd == NULL) {
    fprintf(stderr, "(%s) Could not open source '%s'.\n", __FILE__, source);
    exit(1);
  }
  
  vmg = ifoOpen(dvd, 0);
  if (vmg == NULL) {
    fprintf(stderr, "(%s) Can't open VMG info.\n", __FILE__);
    DVDClose(dvd);
    exit(1);
  }
  
  tt_srpt = vmg->tt_srpt;
  if (verbose)
    fprintf(stderr, "(%s) This DVD contains %d titles.\n", __FILE__,
            tt_srpt->nr_of_srpts);
  if (title > tt_srpt->nr_of_srpts) {
    fprintf(stderr, "(%s) The DVD only contains %d titles.\n", __FILE__,
            tt_srpt->nr_of_srpts);
    ifoClose(vmg);
    DVDClose(dvd);
    exit(1);
  }
  title--;
  if (verbose)
    fprintf(stderr, "(%s) Title %d contains %d chapters.\n", __FILE__,
            title + 1, tt_srpt->title[title].nr_of_ptts);

  vts = ifoOpen(dvd, tt_srpt->title[title].title_set_nr);
  if (vts == NULL) {
    fprintf(stderr, "(%s) Can't open VTS info.\n", __FILE__);
    ifoClose(vmg);
    DVDClose(dvd);
    exit(1);
  }

  if (end > 0) {
    if ((end <= start) || (end > tt_srpt->title[title].nr_of_ptts)) {
      fprintf(stderr, "(%s) Invalid end chapter.\n", __FILE__);
      ifoClose(vmg);
      DVDClose(dvd);
      exit(1);
    }
  }
  
  ttn = tt_srpt->title[title].vts_ttn;
  vts_ptt_srpt = vts->vts_ptt_srpt;
  start_time = overall_time = 0;
  for (i = 0; i < tt_srpt->title[title].nr_of_ptts - 1; i++) {
    pgc_id = vts_ptt_srpt->title[ttn - 1].ptt[i].pgcn;
    pgn = vts_ptt_srpt->title[ttn - 1].ptt[i].pgn;
    cur_pgc = vts->vts_pgcit->pgci_srp[pgc_id - 1].pgc;
    start_cell = cur_pgc->program_map[pgn - 1] - 1;
    pgc_id = vts_ptt_srpt->title[ttn - 1].ptt[i + 1].pgcn;
    pgn = vts_ptt_srpt->title[ttn - 1].ptt[i + 1].pgn;
    cur_pgc = vts->vts_pgcit->pgci_srp[pgc_id - 1].pgc;
    end_cell = cur_pgc->program_map[pgn - 1] - 2;
    cur_time = 0;
    for (j = start_cell; j <= end_cell; j++) {
      dt = &cur_pgc->cell_playback[j].playback_time;
      hour = ((dt->hour & 0xf0) >> 4) * 10 + (dt->hour & 0x0f);
      minute = ((dt->minute & 0xf0) >> 4) * 10 + (dt->minute & 0x0f);
      second = ((dt->second & 0xf0) >> 4) * 10 + (dt->second & 0x0f);
      if (((dt->frame_u & 0xc0) >> 6) == 1)
        fps = 25.00;
      else
        fps = 29.97;
      dt->frame_u &= 0x3f;
      dt->frame_u = ((dt->frame_u & 0xf0) >> 4) * 10 + (dt->frame_u & 0x0f);
      ms = (double)dt->frame_u * 1000.0 / fps;
      cur_time += (hour * 60 * 60 * 1000 + minute * 60 * 1000 + second * 1000 +
                   ms);
    }
    if (start == i)
      start_time = overall_time;
    if (i >= start && (i < end || end <= 0))
    {
      fprintf(stdout, "CHAPTER%02d=%02ld:%02ld:%02ld.%03ld\n", i + 1 - start,
              (overall_time - start_time) / 60 / 60 / 1000,
              ((overall_time - start_time) / 60 / 1000) % 60,
              ((overall_time - start_time) / 1000) % 60,
              (overall_time - start_time) % 1000);
      fprintf(stdout, "CHAPTER%02dNAME=Chapter %02d\n", i + 1 - start,
              i + 1 - start);
    }
    overall_time += cur_time;
  }
  if (end <= 0 || i == end)
  {
    fprintf(stdout, "CHAPTER%02d=%02ld:%02ld:%02ld.%03ld\n", i + 1 - start,
            (overall_time - start_time) / 60 / 60 / 1000,
            ((overall_time - start_time) / 60 / 1000) % 60,
            ((overall_time - start_time) / 1000) % 60,
            (overall_time - start_time) % 1000);
    fprintf(stdout, "CHAPTER%02dNAME=Chapter %02d\n", i + 1 - start, i + 1 - start);
  }
  
  ifoClose(vts);
  ifoClose(vmg);
  DVDClose(dvd);
}

int main(int argc, char *argv[]) {
  int  title = 1;
  int  start = 0, end = 0;
  int  i;
  char *source = NULL;
  int  verbose = 0;
  
  if (argc == 1) {
    usage();
    exit(0);
  }
  for (i = 1; i < argc; i++) {
    if (!strcmp(argv[i], "-h") || !strcmp(argv[i], "--help")) {
      usage();
      exit(0);
    } else if (!strcmp(argv[i], "-v") || !strcmp(argv[i], "--verbose"))
      verbose++;
    else if (!strcmp(argv[i], "-V") || !strcmp(argv[i], "--version")) {
      fprintf(stdout, "dvdxchap v" VERSION "\n");
      exit(0);
    } else if (!strcmp(argv[i], "-t") || !strcmp(argv[i], "--title")) {
      if ((i + 1) >= argc) {
        fprintf(stderr, "(%s) Error: -t lacks a title number.\n", __FILE__);
        exit(1);
      }
      title = strtol(argv[i + 1], NULL, 10);
      if ((errno == ERANGE) || (errno == EINVAL) || (title < 1)) {
        fprintf(stderr, "(%s) Error: '%s' is not a valid title number.\n", 
                __FILE__, argv[i + 1]);
        exit(1);
      }
      i++;
    } else if (!strcmp(argv[i], "-c") || !strcmp(argv[i], "--chapter")) {
      if ((i + 1) >= argc) {
        fprintf(stderr, "(%s) Error: -c lacks a chapter number.\n", __FILE__);
        exit(1);
      }
      if (sscanf(argv[i + 1], "%d-%d", &start, &end) < 1) {
        fprintf(stderr, "(%s) Error: '%s' is not a valid chapter range.\n", 
                __FILE__, argv[i + 1]);
        exit(1);
      }
      if (start < 0) {
        end = -start;
        start = 0;
      }
      if ((start > end) && (end > 0)) {
        int tmp;
        tmp = start;
        start = end;
        end = tmp;
      }
      if (start > 0)
        start--;
      i++;
    } else {
      if (source != NULL) {
        fprintf(stderr, "(%s) Error: more than one source given.\n", __FILE__);
        exit(1);
      }
      source = argv[i];
    }
  }
  if (source == NULL) {
    fprintf(stderr, "(%s) Error: No source given.\n", __FILE__);
    exit(1);
  }

  display_chapters(source, title, start, end, verbose);

  return 0;
}