/*

    File: sessionp.c

    Copyright (C) 2006-2007 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
#include <stdio.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>	/* unlink */
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <errno.h>
#include "types.h"
#include "common.h"
#include "intrf.h"
#include "filegen.h"
#include "sessionp.h"
#include "log.h"

#define SESSION_MAXSIZE 40960
#define SESSION_FILENAME "photorec.ses"

static int session_create_empty(void);

static int session_create_empty()
{
  int res;
  FILE *f_session;
  char *buffer;
  f_session=fopen(SESSION_FILENAME,"wb");
  if(!f_session)
  {
    log_critical("Can't create empty photorec.ses file: %s\n",strerror(errno));
    return -1;
  }
  buffer=MALLOC(SESSION_MAXSIZE);
  memset(buffer,0,SESSION_MAXSIZE);
  res=fwrite(buffer,SESSION_MAXSIZE,1,f_session);
  free(buffer);
  fclose(f_session);
  return (res<=0?-1:0);
}

int session_load(char **cmd_device, char **current_cmd, alloc_data_t *list_free_space)
{
  FILE *f_session;
  char *buffer;
  char *pos;
  int taille;
  f_session=fopen(SESSION_FILENAME,"rb");
  if(!f_session)
  {
    log_info("Can't read photorec.ses file: %s\n",strerror(errno));
    session_create_empty();
    return -1;
  }
  buffer=MALLOC(SESSION_MAXSIZE);
  taille=fread(buffer,1,SESSION_MAXSIZE,f_session);
  fclose(f_session);
  buffer[(taille<SESSION_MAXSIZE?taille:SESSION_MAXSIZE-1)]='\0';
  pos=buffer;
  if(*pos=='#')
  {
    time_t my_time;
    char *info=NULL;
    pos++;
    /* load time */
    my_time=strtol(pos,&pos,10);
    if(pos==NULL)
    {
      free(buffer);
      return 0;
    }
    pos=strstr(pos,"\n");
    if(pos==NULL)
    {
      free(buffer);
      return 0;
    }
    pos++;
    /* get current disk */
    info=pos;
    pos=strstr(info," ");
    if(pos==NULL)
    {
      free(buffer);
      return 0;
    }
    *pos='\0';
    pos++;
    *cmd_device=strdup(info);
    /* search part_name_option */
    info=pos;
    pos=strstr(pos,"\n");
    if(pos==NULL)
    {
      free(buffer);
      return 0;
    }
    *pos='\0';
    pos++;
    *current_cmd=strdup(info);
    do
    {
      long unsigned start,end;
      if(sscanf(pos,"%lu-%lu\n",&start,&end)==2)
      {
	if(start<=end)
	{
	  alloc_data_t *new_free_space;
	  new_free_space=(alloc_data_t*)MALLOC(sizeof(*new_free_space));
	  /* Temporary storage, values need to be multiply by sector_size */
	  new_free_space->start=start;
	  new_free_space->end=end;
	  new_free_space->file_stat=NULL;
	  list_add_tail(&new_free_space->list, &list_free_space->list);
#ifdef DEBUG
	  log_trace(">%lu-%lu<\n",start,end);
#endif
	}
	pos=strstr(pos,"\n");
	if(pos!=NULL)
	  pos++;
      }
      else
	pos=NULL;
    } while(pos!=NULL);
  }
  free(buffer);
  return 0;
}

int session_save(alloc_data_t *list_free_space, disk_t *disk_car, const partition_t *partition, const file_enable_t *files_enable, const unsigned int blocksize, const int debug)
{
  struct list_head *free_walker = NULL;
  FILE *f_session;
  unsigned int i;
  if(debug>1)
  {
    log_trace("session_save\n");
  }
  f_session=fopen(SESSION_FILENAME,"wb");
  if(!f_session)
  {
    log_critical("Can't create photorec.ses file: %s\n",strerror(errno));
    return -1;
  }
  fprintf(f_session,"#%u\n%s %s,%u,blocksize,%u,fileopt,",(unsigned int)time(NULL), disk_car->device, disk_car->arch->part_name_option, partition->order,blocksize);
  for(i=0;files_enable[i].file_hint!=NULL;i++)
  {
    if(files_enable[i].file_hint->extension!=NULL && files_enable[i].file_hint->extension[0]!='\0')
    {
      fprintf(f_session,"%s,%s,",files_enable[i].file_hint->extension,(files_enable[i].enable!=0?"enable":"disable"));
    }
  }
  fprintf(f_session,"search,inter\n");
  list_for_each(free_walker, &list_free_space->list)
  {
    alloc_data_t *current_free_space;
    current_free_space=list_entry(free_walker, alloc_data_t, list);
    fprintf(f_session,"%lu-%lu\n",(long unsigned)(current_free_space->start/disk_car->sector_size),
	(long unsigned)(current_free_space->end/disk_car->sector_size));
  }
  fclose(f_session);
  return 0;
}