#!/usr/bin/perl -w

open IN, $ARGV[0] or die "Can't read '$ARGV[0]': $!";
open OUT, ">$ARGV[1]" or die "Can't write to '$ARGV[1]': $!";
binmode OUT;

my $c = 0;
my %countries;
while( <IN> ) {
    my( $fromip, $toip, $from, $to, $ccode, $country ) = map { /^"(.*)"$/; $1 } split /,/, $_;

    die "$_: $from, $c\n" if( $from < $c ); # unordered or overlapping ranges
    die if( length $ccode != 2 );           # malformed country code

    if( $from > $c ) {
        print OUT pack 'N', ($c>>1); print OUT '??';
        $c = $from;
    }
    print OUT pack 'N', ($c>>1); print OUT $ccode;
    $c = $to+1;
    $countries{$ccode} = 1;
}
close IN;

# end of final range
print OUT pack 'N', ($c>>1); print OUT '??';
# end of entire IP range (255.255.255.255)
print OUT pack 'N', (0xffffffff>>1); print OUT '??';

close OUT;

print "There are ".scalar( keys %countries )." countries:\n";
print join ", ", sort keys %countries;
print "\n";