/*

    File: file_crw.c

    Copyright (C) 1998-2005,2007 Christophe GRENIER <grenier@cgsecurity.org>
  
    This software 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 2 of the License, or
    (at your option) any later version.
  
    This program 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, write the Free Software Foundation, Inc., 51
    Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include <stdio.h>
#include "types.h"
#include "filegen.h"
#include "log.h"

static void register_header_check_crw(file_stat_t *file_stat);
static int header_check_crw(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new);
static int data_check_crw(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery);

const file_hint_t file_hint_crw= {
  .extension="crw",
  .description="Canon Raw picture",
  .min_header_distance=0,
  .max_filesize=PHOTOREC_MAX_FILE_SIZE,
  .recover=1,
  .header_check=&header_check_crw,
  .register_header_check=&register_header_check_crw
};

static const unsigned char crw_header_be[2]= {'I','I'};
static const unsigned char crw_header_le[2]= {'M','M'};

static void register_header_check_crw(file_stat_t *file_stat)
{
  register_header_check(0, crw_header_be, sizeof(crw_header_be), &header_check_crw, file_stat);
  register_header_check(0, crw_header_le, sizeof(crw_header_le), &header_check_crw, file_stat);
}

static int header_check_crw(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new)
{
  if(((buffer[0]==0x49 && buffer[1]==0x49)||(buffer[0]==0x4D && buffer[1]==0x4D))
      && memcmp(buffer+6,"HEAPCCDR",8)==0)
  {
    reset_file_recovery(file_recovery_new);
    file_recovery_new->extension=file_hint_crw.extension;
    file_recovery_new->data_check=&data_check_crw;
    file_recovery_new->file_check=&file_check_size;
    return 1;
  }
  return 0;
}

static int data_check_crw(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
{
  unsigned int i;
  for(i=(buffer_size/2)-13;i+13<buffer_size;i++)
  {
    if(buffer[i]==0x0A && buffer[i+1]==0x30 && buffer[i+2]==0xFE && buffer[i+3]==0x17 && buffer[i+13]==0)
    {
      file_recovery->calculated_file_size=file_recovery->file_size+i+14-(buffer_size/2);
      log_debug("EOF CRW found\n");
      return 2;
    }
  }
  file_recovery->calculated_file_size=file_recovery->file_size+(buffer_size/2);
  return 1;
}