#!/usr/bin/perl

use Math::BigInt;



$verb = 0 ;
$verb2 = 0 ; # show time

# http://www.stumbler.net/ns1files.html
# C uint8 S uint16 L uint32 l int32 Q uint64 d double

# Flags  (HEx)
# 0001 ESS extended service set
# 0002 IBSS  ad hod/P2P
# 0004 CF Pollable
# 0008 CF-Poll request
# 0010 WEP
# 0020 Short Preamble
# 0040 PBCC
# 0080 Channel Agility
# 0400 Short slot time
# 2000 DSSS-OFDM

$type = 'BSS' ; $bcni = 100 ;
$quiet = 0 ;
                                                                                
while ($ARGV[0] =~ /-([nedv])/) {
  if ($1 eq 'n') { shift ; $legend = 1 ; }
  if ($1 eq 'e') { shift ; $doe = 1 ; }
  if ($1 eq 'd') { shift ; $dp1 = 1 ; }
  if ($1 eq 'v') { shift ; $verb = 1 ; }
}
$file = shift ;
open (IN,$file) or die "Usage: $0 [-nedv] <file.ns1>\n" ;

read (IN,$in,4) ;

unless ($in eq 'NetS') {
  die  "$file has no NetStumbler magic\n" ;
}
read (IN,$in,4) ;
$fv = unpack("L",$in) ;

print<<EOT;
# \$Creator $0
# File version $fv\n" ;
# \$Format: wi-scan with extensions
# Latitude	Longitude	( SSID )	Type	( BSSID )	Time (GMT)	[ SNR Sig Noise ]	# ( Name )	Flags	Channelbits	BcnIntvl	DataRate	LastChannel
EOT

read (IN,$in,4) ;
$nap = unpack("L",$in) ;

print STDERR "$nap APINFO entries\n" ;
for ($ap=1;$ap<=$nap;$ap++) {
#  print "\nAP $ap\n" ;
#  print "\n" ;
  read (IN,$in,1) ;
  $ssidlen = unpack("C",$in) ;
  read (IN,$in,$ssidlen) ;

  $ssid = $in ;
  #print "SSID $ssid\t" ;

  read (IN,$in,6) ; @bssid = unpack("C6",$in) ;

  $bssid = sprintf("%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x", $bssid[0],$bssid[1],$bssid[2],$bssid[3],$bssid[4],$bssid[5]) ;
  $ssid{$bssid} = $ssid ;
  read (IN,$in,4) ; $maxsig = unpack("l",$in) ; $maxsig{$bssid} = $maxsig ;
  read (IN,$in,4) ; $minns  = unpack("l",$in) ; $minns{$bssid} = $minns ;
  read (IN,$in,4) ; $maxsnr = unpack("l",$in) ; $maxsnr{$bssid} =  $maxsnr;

  #print "maxsig $maxsig min noise $minns max SNR $maxsnr\n" ;
  #print "\t$maxsig $minns $maxsnr" ;

  read (IN,$in,4) ; $flags = unpack("L",$in) ;
  $wep = $flags & 0x10 ;
  $fast = $flags & 0x2400  ;
  $hflags = sprintf("%4.4x", $flags) ;
  #printf ("\tflags %4.4x", $flags) ;
  read (IN,$in,4) ; $bint = unpack("L",$in) ;
  #print "\tb.int $bint" ;

  read (IN,$in,8) ; 
  $first = filetotime($in) ;
  ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = gmtime($first) ;
  $year += 1900 ; $mon ++ ;
  $date = sprintf("%2.2d:%2.2d:%2.2d (GMT)",$hour,$min,$sec) ;
  unless ($dategmt) {
    $dategmt = sprintf("\# \$DateGMT: %4.4d-%2.2d-%2.2d",$year,$mon,$mday) ;
    print "$dategmt\n" ;
  }
  read (IN,$in,8) ; 
#  $last = filetotime($in) ; $dt = $last - $first ;
#  $ff = localtime($last) ;
  #print "\tfor $dt sec\n" ;

  # http://blogs.msdn.com/oldnewthing/archive/2003/09/05/54806.aspx
  # http://maillist.perforce.com/pipermail/jamming/1997-August/000294.html

  read (IN,$in,8) ; $lat =  unpack("d",$in) ;
  read (IN,$in,8) ; $long =  unpack("d",$in) ;

  if ($lat < 0) { 
    $lat = sprintf("S %.6f",-$lat) ;
  } else {
    $lat = sprintf("N %.6f",$lat) ;
  }
  if ($long < 0) {
    $long = sprintf("W  %.6f",-$long) ;
  } else {
    $long = sprintf("E  %.6f",$long) ;
  }
  #printf("\tLL %.6f %.6f\n",$lat,$long) ;



  read (IN,$in,4) ; $ndata = unpack("L",$in) ;

  #print "$ndata data entries\n" ;

  for ($i=0;$i<$ndata;$i++) {
    read (IN,$in,8) ;
    if ($verb and $verb2) { $time = filetotime($in) ; $ltime = localtime($time) ; }
    read (IN,$in,4) ; $sig  = unpack("l",$in) ;
    read (IN,$in,4) ; $noise  = unpack("l",$in) ;
    read (IN,$in,4) ; $fix  = unpack("l",$in) ;
    #if ($verb) { print "\t$ltime\t$sig\t$noise\t" ; }
    if ($fix) {
      read (IN,$in,8) ; $lat =  unpack("d",$in) ;
      read (IN,$in,8) ; $long =  unpack("d",$in) ;
      read (IN,$in,8) ; $alt =  unpack("d",$in) ;
      read (IN,$in,4) ; $nsat = unpack("L",$in) ;
      read (IN,$in,8) ; $speed =  unpack("d",$in) ;
      read (IN,$in,8) ; $track  =  unpack("d",$in) ;
      read (IN,$in,8) ; $mvar =  unpack("d",$in) ;
      read (IN,$in,8) ; $hdop =  unpack("d",$in) ;
      if ($lat < 0) {
	$lat = sprintf("S %.6f",-$lat) ;
      } else {
	$lat = sprintf("N %.6f",$lat) ;
      }
      if ($long < 0) {
	$long = sprintf("W  %.6f",-$long) ;
      } else {
	$long = sprintf("E  %.6f",$long) ;
      }

      #print "  LL $lat $long alt $alt Nsat $nsat speed $speed track $track Mvar $mvar hdop $hdop\n" ;
	$x = $xscale * ($long - $xoff) / 180 ; $y = $yscale * ($lat - $yoff) / 180 ; # from worldmap.c
	if ($xmax eq '') { $xmax = $xmin = $x ; }
	if ($ymax eq '') { $ymax = $ymin = $y ; }
	if ($x>$xmax) { $xmax = $x ; }
	if ($y>$ymax) { $ymax = $y ; }
	if ($x<$xmin) { $xmin = $x ; }
	if ($y<$ymin) { $ymin = $y ; }
	$x = int($x * $scale2 + 0.5 ) ; $y = int($y * -$scale2 + 0.5 ) ; # from ps2fig
        $x{$bssid} = $x ; $y{$bssid} = $y ;
      if ($verb) { 
        $rate10 = $maxrate * 10 ;
        $snr = $sig - $noise ;
        print "$lat\t$long\t( $ssid )\t$type\t( $bssid )\t$date\t[ $snr $sig $noise ]\t\# ( $name )\t$hflags\t$cbits\t$bcni\t$rate10\t$lchan\n" ;

      }
    } else {
      #if ($verb) { print "\n" ; }
    }
  }

  read (IN,$in,1) ; $len = unpack("C",$in) ;
  read (IN,$in,$len) ; $name = $in ; $name{$bssid} = $name ;
  if ($fv >= 8) {
    read (IN,$in,8) ; @chan = unpack("L2",$in) ;
    read (IN,$in,4) ; $lchan = unpack("L",$in) ; $lchan{$bssid} = $lchan ;
    read (IN,$in,4) ; $ip = unpack("L",$in) ; @ip = unpack("C4",$in) ;
    #printf ("channelbits %4.4x%4.4x",$chan[1], $chan[0]) ;
    #printf ("\tip %i.%i.%i.%i lastchan %i\n",$ip[0],$ip[1],$ip[2],$ip[3],$lchan) ;
  }
  if ($fv >= 11 ) {
    read (IN,$in,4) ; $minsig = unpack("l",$in) ; $minsig{$bssid} = $minsig ;
    read (IN,$in,4) ; $maxns = unpack("l",$in) ; $maxns{$bssid} = $maxns ;
    read (IN,$in,4) ; $maxrate = unpack("L",$in)/10  ; $maxrate{$bssid} = $maxrate ;
    read (IN,$in,4) ; $subnet  = unpack("L",$in) ; @subnet = unpack("C4",$in) ;
    read (IN,$in,4) ; $mask  = unpack("L",$in) ; @mask = unpack("C4",$in) ;
    #printf ("min sig %i max noise %i max rate %i subnet %i.%i.%i.%i mask %i.%i.%i.%i\n",$minsig,$maxns,$maxrate,$subnet[0],$subnet[1],$subnet[2],$subnet[3], $mask[0],$mask[1],$mask[2],$mask[3]) ;
  }
  if ($fv >= 12) {
    read (IN,$in,4) ; $miscflags  = unpack("L",$in) ;
    #if ($miscflags) { printf ("misc flags %4.4x\n", $miscflags) ; }
    read (IN,$in,4) ; $ielength  = unpack("L",$in) ;
    read (IN,$in,$ielength) ; @ie = unpack("C*",$in) ;
    #if ($ielength) { print "ie length $ielength\n" ; }
  }

  unless ($verb) {
    $rate10 = $maxrate * 10 ;
    $snr = $sig - $noise ;
    print "$lat\t$long\t( $ssid )\t$type\t( $bssid )\t$date\t[ $snr $sig $noise ]\t\# ( $name )\t$hflags\t$cbits\t$bcni\t$rate10\t$lchan\n" ;
  }



}


exit ;

sub filetotime {
  my ($h,$l,$t,$r) ;
  ($l,$h) = unpack("L2",$_[0]) ;

  my $t = Math::BigInt->new($h);
  $t->blsft(32) ;
  $t->badd($l) ;

  $t->bdiv(10000000) ; # convert 100ns ticks to seconds
  $t->bsub("11644473600") ; # 134774 days = 369 years 1601 - 1970
  return $t ;
}