/*
 * GeoIPCity.c
 *
 * Copyright (C) 2006 MaxMind LLC
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the
 * Free Software Foundation; either version 2.1 of the License, or (at your
 * option) any later version.
 *
 * This library 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 Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <GeoIP.h>
#include <GeoIP_internal.h>
#include <GeoIPCity.h>
#if !defined(_WIN32)
#include <unistd.h>
#include <netdb.h>
#include <netinet/in.h>	/* For ntohl */
#else
#include <windows.h>
#include <winsock.h>
#endif
#include <sys/types.h>	/* For uint32_t */
#ifdef HAVE_STDINT_H
#include <stdint.h>	/* For uint32_t */
#endif

static
const int       FULL_RECORD_LENGTH = 50;

static const int CITYCONFIDENCE_FIXED_RECORD = 4;
static const int CITYCONFIDENCEDIST_FIXED_RECORD = 6;


static
GeoIPRecord    *
_extract_record(GeoIP * gi, unsigned int seek_record, int *next_record_ptr)
{
  int             record_pointer;
  unsigned char  *record_buf = NULL;
  unsigned char  *begin_record_buf = NULL;
  GeoIPRecord    *record;
  int             str_length = 0;
  int             j;
  double          latitude = 0, longitude = 0;
  int             metroarea_combo = 0;
  int             bytes_read = 0;
  if (seek_record == gi->databaseSegments[0])
    return NULL;

  record = malloc(sizeof(GeoIPRecord));
  memset(record, 0, sizeof(GeoIPRecord));
  record->charset = gi->charset;

  if (gi->databaseType == GEOIP_CITYCONFIDENCE_EDITION
      || gi->databaseType == GEOIP_CITYCONFIDENCEDIST_EDITION) {

    int             fixed_rec_size = gi->record_length +
    ((gi->databaseType == GEOIP_CITYCONFIDENCE_EDITION)
     ? CITYCONFIDENCE_FIXED_RECORD
     : CITYCONFIDENCEDIST_FIXED_RECORD);

    //allocate max rec size, even for CITYCONFIDENCE_FIXED_RECORD
      //+4 is the max_record_length
	// TODO
	unsigned char   tmp_fixed_record[6/*CITYCONFIDENCEDIST_FIXED_RECORD*/ + 4];
    int             dseg = gi->databaseSegments[0] * gi->record_length * 2 + gi->record_length;
//    int aligned_dseg = dseg ;

    int             offset = seek_record - gi->databaseSegments[0] - 1;	/* -1 b/c zero is not
									 * found. but the array
									 * start with 0 */
    record_pointer = offset * fixed_rec_size + dseg + gi->dyn_seg_size;
    if (gi->cache == NULL) {

	/* read from disk */
      bytes_read = pread(fileno(gi->GeoIPDatabase), tmp_fixed_record, fixed_rec_size, record_pointer);

      if (bytes_read != fixed_rec_size)
	return NULL;

      record->country_conf = tmp_fixed_record[0];
      record->region_conf = tmp_fixed_record[1];
      record->city_conf = tmp_fixed_record[2];
      record->postal_conf = tmp_fixed_record[3];

      record->accuracy_radius =
	gi->databaseType == GEOIP_CITYCONFIDENCEDIST_EDITION
	? ((tmp_fixed_record[4] + (tmp_fixed_record[5] << 8)) & 0x3ff) : 0x3ff;

      int             t = fixed_rec_size - gi->record_length;
      
    record_pointer = dseg + tmp_fixed_record[t] +
	(tmp_fixed_record[t + 1] << 8) + (tmp_fixed_record[t + 2] << 16) ;

    if (gi->record_length == 4)
	record_pointer += (tmp_fixed_record[t + 3] << 24);

      begin_record_buf = record_buf = malloc(sizeof(char) * FULL_RECORD_LENGTH);

      bytes_read = pread(fileno(gi->GeoIPDatabase), record_buf, FULL_RECORD_LENGTH, record_pointer);
      
      if (bytes_read == 0) {
	/* eof or other error */
	free(begin_record_buf);
	free(record);
	return NULL;
      }

    }
    else {
      record_buf = gi->cache + (long) record_pointer;

      record->country_conf = record_buf[0];
      record->region_conf = record_buf[1];
      record->city_conf = record_buf[2];
      record->postal_conf = record_buf[3];

      record->accuracy_radius =
	gi->databaseType == GEOIP_CITYCONFIDENCEDIST_EDITION
	? ((record_buf[4] + (record_buf[5] << 8)) & 0x3ff) : 0x3ff;

      int             t = fixed_rec_size - gi->record_length;

        record_pointer = dseg + record_buf[t] +
	(record_buf[t + 1] << 8) + (record_buf[t + 2] << 16) ;
     
     if (gi->record_length == 4)
	record_pointer += (record_buf[t + 3] << 24);

      record_buf = gi->cache + (long) record_pointer;
    }

  }			/* other city records */
  else {

    record->country_conf = GEOIP_UNKNOWN_CONF;
    record->region_conf = GEOIP_UNKNOWN_CONF;
    record->city_conf = GEOIP_UNKNOWN_CONF;
    record->postal_conf = GEOIP_UNKNOWN_CONF;
    record->accuracy_radius = GEOIP_UNKNOWN_ACCURACY_RADIUS;

    record_pointer = seek_record + (2 * gi->record_length - 1) * gi->databaseSegments[0];

    if (gi->cache == NULL) {
      begin_record_buf = record_buf = malloc(sizeof(char) * FULL_RECORD_LENGTH);
        bytes_read = pread(fileno(gi->GeoIPDatabase), record_buf, FULL_RECORD_LENGTH, record_pointer);
      if (bytes_read == 0) {
        /* eof or other error */
	free(begin_record_buf);
        free(record);
	return NULL;
      }
    }
    else {
      record_buf = gi->cache + (long) record_pointer;
    }
  }

  /* get country */
  record->continent_code = (char *) GeoIP_country_continent[record_buf[0]];
  record->country_code = (char *) GeoIP_country_code[record_buf[0]];
  record->country_code3 = (char *) GeoIP_country_code3[record_buf[0]];
  record->country_name = (char *) GeoIP_country_name_by_id(gi, record_buf[0]);
  record_buf++;

  /* get region */
  while (record_buf[str_length] != '\0')
    str_length++;
  if (str_length > 0) {
    record->region = malloc(str_length + 1);
    strncpy(record->region, (char *) record_buf, str_length + 1);
  }
  record_buf += str_length + 1;
  str_length = 0;

  /* get city */
  while (record_buf[str_length] != '\0')
    str_length++;
  if (str_length > 0) {
    if (gi->charset == GEOIP_CHARSET_UTF8) {
      record->city = _GeoIP_iso_8859_1__utf8((const char *) record_buf);
    }
    else {
      record->city = malloc(str_length + 1);
      strncpy(record->city, (const char *) record_buf, str_length + 1);
    }
  }
  record_buf += (str_length + 1);
  str_length = 0;

  /* get postal code */
  while (record_buf[str_length] != '\0')
    str_length++;
  if (str_length > 0) {
    record->postal_code = malloc(str_length + 1);
    strncpy(record->postal_code, (char *) record_buf, str_length + 1);
  }
  record_buf += (str_length + 1);

  /* get latitude */
  for (j = 0; j < 3; ++j)
    latitude += (record_buf[j] << (j * 8));
  record->latitude = latitude / 10000 - 180;
  record_buf += 3;

  /* get longitude */
  for (j = 0; j < 3; ++j)
    longitude += (record_buf[j] << (j * 8));
  record->longitude = longitude / 10000 - 180;

  /*
   * get area code and metro code for post April 2002 databases and for US
   * locations
   */
  if (GEOIP_CITY_EDITION_REV1 == gi->databaseType
      || GEOIP_CITYCONFIDENCE_EDITION == gi->databaseType) {
    if (!strcmp(record->country_code, "US")) {
      record_buf += 3;
      for (j = 0; j < 3; ++j)
	metroarea_combo += (record_buf[j] << (j * 8));
      record->metro_code = metroarea_combo / 1000;
      record->area_code = metroarea_combo % 1000;
    }
  }

  if (gi->cache == NULL)
    free(begin_record_buf);

  /* Used for GeoIP_next_record */
  if (next_record_ptr != NULL)
    *next_record_ptr = seek_record + record_buf - begin_record_buf + 3;

  return record;
}

static
GeoIPRecord    *
_get_record(GeoIP * gi, unsigned long ipnum)
{
  unsigned int    seek_record;
  if (gi->databaseType != GEOIP_CITY_EDITION_REV0
      && gi->databaseType != GEOIP_CITY_EDITION_REV1
      && gi->databaseType != GEOIP_CITYCONFIDENCE_EDITION
      && gi->databaseType != GEOIP_CITYCONFIDENCEDIST_EDITION) {
    printf("Invalid database type %s, expected %s\n", GeoIPDBDescription[(int) gi->databaseType], GeoIPDBDescription[GEOIP_CITY_EDITION_REV1]);
    return 0;
  }

  seek_record = _GeoIP_seek_record(gi, ipnum);
  return _extract_record(gi, seek_record, NULL);
}

static
GeoIPRecord    *
_get_record_v6(GeoIP * gi, geoipv6_t ipnum)
{
  unsigned int    seek_record;
  if (gi->databaseType != GEOIP_CITY_EDITION_REV0_V6 &&
      gi->databaseType != GEOIP_CITY_EDITION_REV1_V6) {
    printf("Invalid database type %s, expected %s\n", GeoIPDBDescription[(int) gi->databaseType], GeoIPDBDescription[GEOIP_CITY_EDITION_REV1_V6]);
    return 0;
  }

  seek_record = _GeoIP_seek_record_v6(gi, ipnum);
  return _extract_record(gi, seek_record, NULL);
}



GeoIPRecord    *
GeoIP_record_by_ipnum(GeoIP * gi, unsigned long ipnum)
{
  return _get_record(gi, ipnum);
}

GeoIPRecord    *
GeoIP_record_by_ipnum_v6(GeoIP * gi, geoipv6_t ipnum)
{
  return _get_record_v6(gi, ipnum);
}

GeoIPRecord    *
GeoIP_record_by_addr(GeoIP * gi, const char *addr)
{
  unsigned long   ipnum;
  if (addr == NULL) {
    return 0;
  }
  ipnum = GeoIP_addr_to_num(addr);
  return _get_record(gi, ipnum);
}

GeoIPRecord    *
GeoIP_record_by_addr_v6(GeoIP * gi, const char *addr)
{
  geoipv6_t       ipnum;
  if (addr == NULL) {
    return 0;
  }
  ipnum = _GeoIP_addr_to_num_v6(addr);
  return _get_record_v6(gi, ipnum);
}

GeoIPRecord    *
GeoIP_record_by_name(GeoIP * gi, const char *name)
{
  unsigned long   ipnum;
  if (name == NULL) {
    return 0;
  }
  ipnum = _GeoIP_lookupaddress(name);
  return _get_record(gi, ipnum);
}

GeoIPRecord    *
GeoIP_record_by_name_v6(GeoIP * gi, const char *name)
{
  geoipv6_t       ipnum;
  if (name == NULL) {
    return 0;
  }
  ipnum = _GeoIP_lookupaddress_v6(name);
  return _get_record_v6(gi, ipnum);
}

int
GeoIP_record_id_by_addr(GeoIP * gi, const char *addr)
{
  unsigned long   ipnum;
  if (gi->databaseType != GEOIP_CITY_EDITION_REV0 &&
      gi->databaseType != GEOIP_CITY_EDITION_REV1) {
    printf("Invalid database type %s, expected %s\n", GeoIPDBDescription[(int) gi->databaseType], GeoIPDBDescription[GEOIP_CITY_EDITION_REV1]);
    return 0;
  }
  if (addr == NULL) {
    return 0;
  }
  ipnum = GeoIP_addr_to_num(addr);
  return _GeoIP_seek_record(gi, ipnum);
}

int
GeoIP_record_id_by_addr_v6(GeoIP * gi, const char *addr)
{
  geoipv6_t       ipnum;
  if (gi->databaseType != GEOIP_CITY_EDITION_REV0_V6 &&
      gi->databaseType != GEOIP_CITY_EDITION_REV1_V6) {
    printf("Invalid database type %s, expected %s\n", GeoIPDBDescription[(int) gi->databaseType], GeoIPDBDescription[GEOIP_CITY_EDITION_REV1]);
    return 0;
  }
  if (addr == NULL) {
    return 0;
  }
  ipnum = _GeoIP_addr_to_num_v6(addr);
  return _GeoIP_seek_record_v6(gi, ipnum);
}

int
GeoIP_init_record_iter(GeoIP * gi)
{
  return gi->databaseSegments[0] + 1;
}

int
GeoIP_next_record(GeoIP * gi, GeoIPRecord ** gir, int *record_iter)
{
  if (gi->cache != NULL) {
    printf("GeoIP_next_record not supported in memory cache mode\n");
    return 1;
  }
  *gir = _extract_record(gi, *record_iter, record_iter);
  return 0;
}

void
GeoIPRecord_delete(GeoIPRecord * gir)
{
  free(gir->region);
  free(gir->city);
  free(gir->postal_code);
  free(gir);
}