#!/usr/bin/perl -w
# sets a page's rank and returns a thank you message
use strict;
use Fcntl ':flock';     # import lock constants.

        # this should be tidied up by using CGI,  Your query string should
        # take the form: ?vote=value&gametitle=value&begin=value&end=value&bypass=value
        # but I suspect that it takes a form more like:
        # ?10&gametitle&0&10&1  or whatever.  :( 
my $myquery = $ENV{'QUERY_STRING'};
my ($myvote,$mygametitle,$mybegin,$myend,$bypasscache) = split(/\&/,$myquery);
$mygametitle =~ tr/\+/ /;
my $mylink =~ tr/\~/\'/;

        # Pick the database number we're dealing with.
my $dbnumber = ($mybegin == 0 ? 1 : 2);

        # lock the lockfile (and hope everything plays by the rules)
open(FORLOCK,"gmlock.pl") or dienice("Rank set script could not open lock file: $!");
flock(FORLOCK, LOCK_EX) or dienice("Rank set script could not gain exclusive ".
                "lock on database: $!");

        # open our dbfile
open(INF, "gmlist$dbnumber.pl")
        or dienice("Rank set script could not open proper game database for reading: $!");
        # read it all in at once
my @ary = <INF>;
close(INF);

        # if mybegin is greater than zero then we'll want to skip some records...
my $skip = 0;
if($mybegin > 0) { $skip = $mybegin - 2; }              # why -2? 

$skip = $skip < 0 ? 0 : $skip;  # sanity checking, skip should have minimum 0
my ($line, $gamenumber) = ("", -1);

        # find our game number.
foreach (@ary)
{
        $gamenumber++;
        next if $skip--;        # skip this line if we haven't reached $mybegin.

        chomp;                  # $_ is the same as $ary[$gamenumber] (well, unchomped)
        $line = $_;
        my ($gmtitle) = split(/\|/,$line);
        if ($gmtitle eq $mygametitle)
        {
                last;           # we've found out gamenumber so end.
        }
}

        # Pull stuff out from our line  
my ($gmtitle,$gmdescription,$gmurl,$totalvalue,$totalvotes,$averagevote,
    $clicks,$visibility,$siteid,$timesince,$lastip) = split(/\|/,$line);

        # calculate new values
my $myavg;
if ($lastip ne $ENV{'REMOTE_ADDR'}) {
        $totalvalue = $totalvalue + $myvote;
        $totalvotes++;
        $averagevote = $totalvalue / $totalvotes;
        $myavg = $averagevote;
}
$lastip = $ENV{'REMOTE_ADDR'};

my $aflag = 0;          # This flags whether we're switching databases

        # Delete the line for gamenumber from the first file
if (($dbnumber == 1) && ($totalvotes > 2)) {

    $ary[$gamenumber] = "";     # This line position is now empty 

    open(OUTF,">gmlist$dbnumber.pl") or
        dienice("Rank set script could not re-open proper database for writing: $!");
    print OUTF @ary;            # everything except line with gamenumber
    close(OUTF);

    $dbnumber = 2;
    open(INF2,"gmlist$dbnumber.pl") or
        dienice("Rank set script could not open proper game database for reading: $!");;
    @ary = <INF2>;
    close(INF2);                # our new @ary.

    $gamenumber = @ary;         # the last position
    $aflag = 1;

}

        # create our new gamennumber line.
$ary[$gamenumber] = "$gmtitle|$gmdescription|$gmurl|$totalvalue|$totalvotes|".
                "$averagevote|$clicks|$visibility|$siteid|$timesince|$lastip\n";

        # if the game is switching databases and this isn't the first entry in this db
        # OR if we're not switching databases but our vote is greater than average and
        # this is not the first entry in this db then ...
if(($aflag ==1 && $gamenumber != 0) || ($aflag != 1 && $myvote >= $myavg && $gamenumber != 0))
{
        my $i = $gamenumber;

                # find the correct place to insert this line.
        while ($i > 0) {
            $i--;
            $line = $ary[$i];
            chomp($line);
            ($gmtitle,$gmdescription,$gmurl,$totalvalue,$totalvotes,
             $averagevote,$clicks,$visibility,$siteid,$timesince,$lastip) = split(/\|/,$line);

                # if our vote passed in through the GET string is >= the 
                # calculated average vote for this game...
            if ($myavg >= $averagevote) {
                        # swap these two.
                my $holder = $ary[$i];
                $ary[$i] = $ary[$gamenumber];
                $ary[$gamenumber] = $holder;
                $gamenumber--;
            }
            else {      # It must be in the correct position now.
                last;
           }
        }

} else {
        my $i = $gamenumber;

                # find the correct place to insert this line.
        while ($i < @ary) {
            $i++;
            $line = $ary[$i];
            chomp($line);
            ($gmtitle,$gmdescription,$gmurl,$totalvalue,$totalvotes,$averagevote,
              $clicks,$visibility,$siteid,$timesince,$lastip) = split(/\|/,$line);

                # if our vote passed in through the GET string is < the
                # calculated average vote for this game...
            if ($myavg < $averagevote) {
                        # swap these two.
                my $holder = $ary[$i];
                $ary[$i] = $ary[$gamenumber];
                $ary[$gamenumber] = $holder;
                $gamenumber++;
            }
            else {      # it must be in the correct position now.
                last;
           }
        }

}

open(OUTF2,">gmlist$dbnumber.pl") or
        dienice("Rank set script could not re-open proper database for writing: $!");
print OUTF2 @ary;
close(OUTF2);
     # release the lock
close(FORLOCK);

# and all the printing out code goes below here