#!/usr/bin/perl
# General linkback stats version 1.0 
# Sami Köykkä 18.5.2002
# samik @ iki.fi   www.pinseri.com
#
# You can distribute this software freely, but I'd appreciate
# a link to www.pinseri.com. Also, if you improve the software,
# send me a copy! 
#
use strict;

#
# CONFIGURATION
# 
# Absolute path to the file that holds the referrer log.
my $file="/home/customers/pinseri/reflog";
# How many seconds to keep referral
my $expire=60*60*24;  # 24 hours
# How many referers to print
my $show=15;
# Max length of URL shown
my $maxlength=35;
# My domain (for filtering out internal refs)
my $mydomain="pinseri.com";
# "Direct link" text
my $dirlink="Kirjanmerkki tai kirjoitettu osoite";
# Exclude direct links (1 = yes, 0 = no)
my $exclude=1;


#
# END CONFIGURATION
#

print "Content-type: text/html\n\n";

my $now=time;
my $ref=$ENV{'HTTP_REFERER'}, "\n";

# add some security: change dangerous characters
$ref=~s/</%3C/g;
$ref=~s/>/%3E/g;
$ref=~s/"/%22/g;

# Read in the old entries
my (%entries, %count, $line, $timestamp, $url);
open (IN, $file) || die "File $file open error: $!";
foreach $line (<IN>) {
    chomp $line;
    ($timestamp, $url)=split(' ', $line);

    if ($timestamp > $now-$expire) {
	$entries{$timestamp}=$url;
	$count{$url}=$count{$url}+1;
    }
}
close(IN);

# Add the newest entry
$entries{$now}=$ref;
$count{$ref}=$count{$ref}+1;

# Print results
my ($counter);
foreach $url (sort {$count{$b}<=>$count{$a}} keys %count) {
    next if ($url=~m/$mydomain/);
    next if ($exclude==1 && $url eq "");
    if ($url eq "") {
	print "$dirlink ($count{$url})<br />\n";
    } else {
	print "<a href=\"$url\" title=\"$url\">", &tidy($url), "</a> ($count{$url})<br />\n";
    }
    $counter++;
    last if ($counter >= $show);
}

# Save 
# (file locking not implemented, should do that sometimes)
open (OUT, ">$file") || die "File $file write error: $!";
foreach $timestamp (keys %entries) {
    print OUT join (' ', $timestamp, $entries{$timestamp}), "\n";
}
close(OUT);

sub tidy {
    #
    # Tidies up the URL before showing it in the site
    #
    my $url=shift;
    my ($result);

    # 
    # add here matches that change urls to more descriptive text
    #
    # --start--
    if ($url=~m[virtual4.wysiwyg.fi/~samik/yossa]) {
	$result="Yössä";
    }
    elsif ($url=~m[virtual4.wysiwyg.fi/~samik/$]) {
	$result="Samin kotisivu";
    }
    elsif ($url=~m[pekkala.info/$]) {
	$result="Pekkaspace HQ";
    }
    elsif ($url=~m[suodatin.com]) {
	$result="Suodatin";
    }
    elsif ($url=~m[google.com]) {
	$result="Google-haku";
    }
    # --end--
    # 
    #
    elsif (length($url)>$maxlength) {
	$result=substr($url, 0, $maxlength) . "...";
    } else {
	$result=$url;
    }
    return $result;
}