#!/usr/bin/perl
print "Content-type:text/html\n\n";
srand(time() ^ ($$ + ($$ << 15)) );

open(INF,"addata.txt");
@grok = <INF>;
close(INF);

@vads = ();

foreach $i (@grok) {
    # added this line in case the file has a blank line in it
    if ($i eq "") {
	next;			# skip to the next loop iteration
    }
    chomp($i);
    ($id,$gif,$url,$alt,$max,$count) = split(/\|/,$i);
    if ($count < $max) {
	push(@vads,$i);
    }    
}

$rid = int(rand(@vads));

if ($rid < 0) {
    # there's been some problem.  Abort.
    exit;
}

$ad = $vads[$rid];
($id,$gif,$url,$alt,$max,$count) = split(/\|/,$ad);
print qq(<a href="$url"><img src="$gif" alt="$alt"></a>\n);

$count = $count + 1;

open(INF,">addata.txt");
flock(INF,2);
seek(INF,0,0);
foreach $i (@grok) {
    chomp($i);
    if ($i eq $ad) {
	print INF "$id|$gif|$url|$alt|$max|$count\n";
    } else {
	print INF "$i\n";
    }
}
close(INF);