#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "deps/coreio/coreio.h"
#include "cdipsr.h"

// Global variables

unsigned long temp_value;


/////////////////////////////////////////////////////////////////////////////

#define FILE core_file
#define fread(buff,sz,cnt,fc) core_fread(fc,buff,sz*cnt)
#define fseek core_fseek
#define ftell core_ftell

unsigned long ask_type(FILE *fsource, long header_position)
{
   unsigned char filename_length;
   unsigned long track_mode;

   fseek(fsource, header_position, SEEK_SET);
   fread(&temp_value, 4, 1, fsource);
   if (temp_value != 0)
      fseek(fsource, 8, SEEK_CUR); // extra data (DJ 3.00.780 and up)
   fseek(fsource, 24, SEEK_CUR);
   fread(&filename_length, 1, 1, fsource);
   fseek(fsource, filename_length, SEEK_CUR);
   fseek(fsource, 19, SEEK_CUR);
   fread(&temp_value, 4, 1, fsource);
   if (temp_value == 0x80000000)
      fseek(fsource, 8, SEEK_CUR); // DJ4
   fseek(fsource, 16, SEEK_CUR);
   fread(&track_mode, 4, 1, fsource);
   fseek(fsource, header_position, SEEK_SET);
   return (track_mode);
}


/////////////////////////////////////////////////////////////////////////////


void CDI_read_track (FILE *fsource, image_s *image, track_s *track)
{
   unsigned char TRACK_START_MARK[10] = { 0, 0, 0x01, 0, 0, 0, 0xFF, 0xFF, 0xFF, 0xFF };
   unsigned char current_start_mark[10];

   fread(&temp_value, 4, 1, fsource);
   if (temp_value != 0)
      fseek(fsource, 8, SEEK_CUR); // extra data (DJ 3.00.780 and up)

   fread(&current_start_mark, 10, 1, fsource);
   if (memcmp(TRACK_START_MARK, current_start_mark, 10)) printf( "Unsupported format: Could not find the track start mark");

   fread(&current_start_mark, 10, 1, fsource);
   if (memcmp(TRACK_START_MARK, current_start_mark, 10)) printf(  "Unsupported format: Could not find the track start mark");

   fseek(fsource, 4, SEEK_CUR);
   fread(&track->filename_length, 1, 1, fsource);
   fseek(fsource, track->filename_length, SEEK_CUR);
   fseek(fsource, 11, SEEK_CUR);
   fseek(fsource, 4, SEEK_CUR);
   fseek(fsource, 4, SEEK_CUR);
   fread(&temp_value, 4, 1, fsource);
   if (temp_value == 0x80000000)
      fseek(fsource, 8, SEEK_CUR); // DJ4
   fseek(fsource, 2, SEEK_CUR);
   fread(&track->pregap_length, 4, 1, fsource);
   fread(&track->length, 4, 1, fsource);
   fseek(fsource, 6, SEEK_CUR);
   fread(&track->mode, 4, 1, fsource);
   fseek(fsource, 12, SEEK_CUR);
   fread(&track->start_lba, 4, 1, fsource);
   fread(&track->total_length, 4, 1, fsource);
   fseek(fsource, 16, SEEK_CUR);
   fread(&track->sector_size_value, 4, 1, fsource);

   switch(track->sector_size_value)
   {
      case 0 : track->sector_size = 2048; break;
      case 1 : track->sector_size = 2336; break;
      case 2 : track->sector_size = 2352; break;
      case 4 : track->sector_size = 2448; break;
      default: printf("Unsupported sector size. value %ld\n", track->sector_size_value);
      	break;
   }

   if (track->mode > 2) printf( "Unsupported format: Track mode not supported");

   fseek(fsource, 29, SEEK_CUR);
   if (image->version != CDI_V2)
   {
      fseek(fsource, 5, SEEK_CUR);
      fread(&temp_value, 4, 1, fsource);
      if (temp_value == 0xffffffff)
         fseek(fsource, 78, SEEK_CUR); // extra data (DJ 3.00.780 and up)
   }
}


void CDI_skip_next_session (FILE *fsource, image_s *image)
{
   fseek(fsource, 4, SEEK_CUR);
   fseek(fsource, 8, SEEK_CUR);
   if (image->version != CDI_V2)
      fseek(fsource, 1, SEEK_CUR);
}

void CDI_get_tracks (FILE *fsource, image_s *image)
{
   fread(&image->tracks, 2, 1, fsource);
}

bool CDI_init (FILE *fsource, image_s *image, const char *fsourcename)
{
   image->length = core_fsize(fsource);

   if (image->length < 8)
   {
	  printf("%s: Image file is too short\n", fsourcename);
	  return false;
   }

   fseek(fsource, image->length-8, SEEK_SET);
   fread(&image->version, 4, 1, fsource);
   fread(&image->header_offset, 4, 1, fsource);

   if ((image->version != CDI_V2 && image->version != CDI_V3 && image->version != CDI_V35)
		 || image->header_offset == 0)
   {
	  printf("%s: Bad image format\n", fsourcename);
	  return false;
   }
   return true;
}

void CDI_get_sessions (FILE *fsource, image_s *image)
{
#ifndef DEBUG_CDI
   if (image->version == CDI_V35)
      fseek(fsource, (image->length - image->header_offset), SEEK_SET);
   else
      fseek(fsource, image->header_offset, SEEK_SET);

#else
   fseek(fsource, 0L, SEEK_SET);
#endif
   fread(&image->sessions, 2, 1, fsource);
}

