#! /usr/local/bin/perl -Tw

# whatbrowser.pl - from the Complete Webmaster
# http://abiglime.com/webmaster
# written by Doug Steinwand <dzs@iname.com>
#
# Keeps a log and displays a bar chart based on the
# browser that is currently being used. To be used as
# a server-side include program, not a CGI script.
#
# path and name for the access log
$logfile="/tmp/access.txt";

# colors
$boxcolor="#002288";
$txtcolor="#ffffff";
$barcolor="#ff0000";
# font size
$fontsize="2";
# box width
$boxwidth="50%";

# Examples of User Agent Strings:
#
# Mozilla/4.04 [en] (X11; U; Linux 2.0.30 i586)
# Mozilla/3.0 WebTV/1.2 (compatible; MSIE 2.0)
# Mozilla/2.0 (compatible; MSIE 3.0; AOL 3.0; Windows 3.1)
# Mozilla/2.0 (compatible; MSIE 3.0B; Win32)
# Mozilla/4.01 (Macintosh; I; PPC)

# Determine browser from the HTTP_USER_AGENT environment variable.
# note: Netscape's numbers may be inflated because many non-
# Netscape broswers claim to be "Mozilla" compatible
$agent=$ENV{HTTP_USER_AGENT};
if ($agent=~/WebTV/i) {
    $agent="WebTV";
} elsif ($agent=~/MSIE/i) {
    $agent="MSIE";
} elsif ($agent=~/Mozilla/i) {
    $agent="Netscape";
} else {
    $agent="Other";
}

# open the log file for read/write access
unless (open FH, "+<$logfile" or open FH, ">$logfile"){
    print "Can't open $logfile: $!\n";
    exit;
}
# exclusive lock
flock FH, 2;
# read the file into %log
while(<FH>) {
    chomp;
    ($k,$v,$i)=split(/\s+/);
    $log{$k}=int($v);
    $ip{$k}=$i;
}
# increase the count for this agent,
# only if it came from a different IP address
if ($ip{$agent} ne $ENV{REMOTE_ADDR}) {
    $log{$agent}++;
    $ip{$agent}=$ENV{REMOTE_ADDR};
	
    # reset to write at the start of the file
    seek FH, 0, 0;
    # write back each key and value
    foreach (sort keys %log) {
	print FH $_," ",$log{$_}," ",$ip{$_},"\n";
    }
    # erase remainder of file, if any
    truncate FH, tell(FH);
}
close FH;

# find the sum
$total=0;
foreach (values %log) { $total+=$_; }
# avoid divide by zero error
$total=1 if $total==0;

print <<EOT;
<table border=2 bgcolor=$boxcolor cellpadding=8 width=$boxwidth>
 <tr>
  <td align=center>
   <a href="http://abiglime.com/webmaster/articles/cgi/120997.htm"
    target=_blank><font color=#ffffff>What Browses Here</font></a>
   <table width=100% bgcolor=$boxcolor border=0 cellpadding=2>
EOT

foreach (sort keys %log) {
    $p=sprintf("%.0f",($log{$_}*100/$total));
    $n=100-$p;
    # draw a bar
    print <<EOT;
<tr>
 <td width=15%><font size=$fontsize color=$txtcolor>$_</font></td>
 <td width=10% align=right><font size=$fontsize color=$txtcolor>$p%</font></td>
 <td width=75%>
  <table width=100% border=0 cellpadding=0 cellspacing=0>
   <tr>
    <td width=$p% bgcolor=$barcolor><font size=$fontsize>&nbsp;</font></td>
    <td width=$n%><font size=$fontsize>&nbsp;</font></td>
   </tr>
  </table>
 </td>
</tr>
EOT
}
print "</table></td></tr></table>\n";