#!/usr/bin/perl -w
##############################################################################
#                                                                            #
# script to track clicks, and switch redirect up if Googlebot comes crawling #
# 									     #
#									     #
##############################################################################
use strict;

my $site = "http://www.la-los-angeles-college.com/";
my $query = &readQuery;
my %query = &httpQueryVars('text', $query);
my %hexQuery = &httpQueryVars('urlencoded', $query);
my %htmlQuery = &httpQueryVars('html', $query);
my $redirect = '';
my $ua = $ENV{'HTTP_USER_AGENT'};
my $camp = $query{'var'};

if ($ua =~ /google/ig ) {
	$redirect = $site; }
else {
	if ($camp eq "tra") {
		# Platt college redirect
		$redirect = "http://4valen.com/clk/idensohoukemumaidon"; }
          }
print "Location: $redirect\n\n";

exit;

#--- Subroutines -----------------------------------------------#

sub readQuery {
        my $string = '';
        if($ARGV[0]) {
                $string = $ARGV[0];
        }
        elsif($ENV{'REQUEST_METHOD'} eq 'GET'){ #method='get'
                $string = $ENV{'QUERY_STRING'};
        }
        elsif($ENV{'REQUEST_METHOD'} eq 'POST') {
                read(STDIN, $string, $ENV{'CONTENT_LENGTH'});   #method='post'
        }
        return $string;
}

sub httpQueryVars {
        #Either "text", "html", "urlencoded", or none
        my $query = pop @_;
        my $type = lc pop(@_);
        my $pair = '';
        my(%query,%hexQuery,%htmlQuery) = ();

        #$query =~ s/%0D%0A/\n/gi;

        #Parse and set the query variables into %query and %hexQuery
        foreach $pair (split(/&/, $query)){                             #Cycle through each value pairs
                my($key, $value) = split(/=/, $pair);           #Separate name and value
                $key =~ tr/+/ /;
                $key =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
                $hexQuery{lc($key)} = $value;           #Assign URL encoded variable to a %hexQuery variable
                next if $type eq 'urlencoded';
                $value =~ tr/+/ /;
                $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
                $query{lc($key)} = $value;              #Assign name and varible to a hash variable
                next if $type eq 'text';
                $htmlQuery{lc($key)} = scalar &htmlEntities($value);
        }

        return %query if $type eq "text";
        return %hexQuery if $type eq "urlencoded";
        return %htmlQuery if $type eq "html";
}

sub htmlEntities {
        my(@array) = ();
        my(@items) = @_;

        for(@items){
                s/&/&/g;
                s/"/"/g;
                s/'/'/g;
                s/</&lt;/g;
                s/>/&gt;/g;
                push(@array, $_);
        }

        return @array if(scalar(@items) > 1);
        return $array[0] if(scalar(@items) == 1);
}