#!/usr/bin/env perl

use v5.10.1;
use strict;
use warnings;
use DBI;
use File::Basename;
use Digest;
use Digest::MD5 qw(md5);
use Digest::SHA qw(sha1 sha224 sha256 sha384 sha512);
use Mcrypt qw(:ALGORITHMS :MODES :FUNCS);

sub encrypt
{
    my ($algo, $key, $data, $mode) = @_;

    my $td = mcrypt_load( $algo, "", $mode, '' );
    mcrypt_init($td, $key, "");

    my $encrypted = mcrypt_encrypt($td, $data);

    mcrypt_end($td);

    return $encrypted;
}

sub my_crypt
{
    my ($key, $content) = @_;

    my $kfirst = pack('H*', substr($key, 0, 64));
    $content = encrypt(SERPENT, $kfirst, $content, ECB);

    if (length $key > 64)
    {
	my $ksec = pack('H*', substr($key, 64, 64));
	$content = encrypt(SERPENT, $ksec, $content, ECB);
    }

    return unpack('H*', $content);
}

#Return number of good solutions
my $exit = 0;

my $root = dirname(__FILE__);

chdir($root);

# First, read PHP configuration to extract some settings
my $profile;
my $submission_dir;

open my $conf, "<", "$root/onyx/config/root.xml";
for my $p (<$conf>)
{
    if ($p =~ /<(?:option|var) name="(.*)">(.*)<\/(?:option|var)>/)
    {
	$profile = $2 if ($1 eq "profile");
	$submission_dir = $2 if ($1 eq "submission_dir");
    }
}
close $conf;

my $end_time = 1999999999;
if (-f "$root/shared/challenge_started")
{
    open my $conf, "<", "$root/shared/challenge_started";
    $end_time = <$conf>;
    close $conf;
    chomp($end_time);
    $end_time += 14400;
}

die("TIME expired!") if time() > $end_time;
die("No DB profile found") if ! $profile;
die("submission_dir is not a directory") if ! $submission_dir || ! -d $submission_dir;

# Read db settings
my %db_settings;
open my $dbprof, "<", "$root/onyx/db/$profile.profile.php";
while (<$dbprof>)
{
    if (/\$___profile\[['"](.+)['"]\] = ['"](.+)['"]/)
    {
	$db_settings{$1} = $2;
    }
}
close $dbprof;

my $dbh;
# List all files to treat
opendir(my $dh, $submission_dir) || die "Can't opendir submission_dir: $!";
for my $f (readdir $dh)
{
    if ($f =~ /^([0-9]+)-([0-9]+)-([a-zA-Z0-9_]+)$/)
    {
	my $good = -1;

	my $team = $1;
	my $theme = $2;
	my $exercice = $3;

	open my $fh, "<", "$submission_dir/$f";
	my %solution;
	$solution{md5} = <$fh>; chomp( $solution{md5} );
	$solution{sha1} = <$fh>; chomp( $solution{sha1} );
	$solution{sha256} = <$fh>; chomp( $solution{sha256} );
	$solution{sha384} = <$fh>; chomp( $solution{sha384} );
	$solution{sha512} = <$fh>; chomp( $solution{sha512} );
	$solution{whirlpool} = <$fh>; chomp( $solution{whirlpool} );
	close $fh;

#	use Data::Dumper;
#	print STDERR Dumper(\%solution);

	$dbh = DBI->connect("DBI:mysql:database=$db_settings{db};host=$db_settings{host};port=3306",
			    $db_settings{user}, $db_settings{pass},
			    {'RaiseError' => 1, 'PrintError' => 1})
	    or die $DBI::errstr if !$dbh;

	query($dbh, "INSERT INTO exercice_tries (id_exercice, id_team, time) VALUES ('$exercice', $team, CURRENT_TIMESTAMP);");

	my $sth = query($dbh, "SELECT format, value FROM exercice_keys WHERE id_exercice = ".$dbh->quote($exercice));

	# Check solutions
	while (my $row = get_row($sth))
	{
	    $good = 1 if ($good == -1);

	    my $type = @$row[0];
	    my $sol = @$row[1];
	    my $filh; my $tmp_solution;

	    if ($type eq "md5") {
		$filh = md5($f);
	    }
	    elsif ($type eq "sha1") {
		$filh = sha1($f);
	    }
	    elsif ($type eq "sha224") {
		$filh = sha224($f);
	    }
	    elsif ($type eq "sha256") {
		$filh = sha256($f);
	    }
	    elsif ($type eq "sha384") {
		$filh = sha384($f);
	    }
	    elsif ($type eq "sha512") {
		$filh = sha512($f);
	    }
	    elsif ($type eq "whirlpool") {
		my $hash = Digest->new( 'Whirlpool' );
		$hash->add( $f );
		$filh = $hash->digest;
	    }
	    else {
		warn "$type not implemented";
	    }

	    $tmp_solution = my_crypt($sol, $filh) if ($filh);

	    #say STDERR "check $type: $solution{$type} vs $tmp_solution";

	    if ($solution{$type} ne $tmp_solution)
	    {
		$good = 0;
		last;
	    }
	}

	# Register solve
	if ($good == -1) {
	    say STDERR localtime().": Exercice $exercice doesn't exist ; given by team $team in theme $theme.";
	}
	elsif ($good == 1)
	{
	    # Check if the exercice exists
	    $sth = query($dbh, "SELECT `require` FROM exercices E WHERE E.id_theme = $theme AND E.id = ".$dbh->quote($exercice));
	    if ($sth->rows)
	    {
		my $row = get_row($sth);

		# Check if the team has solved dependancies
		$sth = query($dbh, "SELECT S.id FROM solved S WHERE S.id_exercice = ".$dbh->quote(@$row[0])) if @$row[0];
		if (! @$row[0] || $sth->rows)
		{
		    # Check if the team has not already solved this exercice
		    $sth = query($dbh, "SELECT S.id FROM solved S WHERE S.id_team = $team AND S.id_exercice = ".$dbh->quote($exercice));
		    if (! $sth->rows)
		    {
			say "resetresetreset:TEAM$team,$theme:SYNCSYN:TEAM$team:SYNC:HOME:SYNC:all:SY";

			say STDERR localtime().": Team $team solve exercice $exercice in $theme";
			query($dbh, "INSERT INTO solved (id_team, id_exercice, time) VALUES ($team, ".$dbh->quote($exercice).", CURRENT_TIMESTAMP);");
			$exit++;
		    }
		    else {
			warn localtime().": Team $team try to solve exercice $exercice in $theme but ALREADY solved it";
		    }
		}
		else {
		    warn localtime().": Team $team try to solve exercice $exercice in $theme but has NOT SOLVED required exercice ".@$row[0];
		}
	    }
	    else {
		warn localtime().": Team $team try to solve exercice $exercice in $theme but does not exist";
	    }
	}
	else {
	    say "Creset:T$team,$theme:SYNC";

	    say STDERR localtime().": Team $team didn't give the correct answer for exercice $exercice.";
	}

	# Remove the file
	unlink("$submission_dir/$f");
    }
}
closedir $dh;

$dbh->disconnect() if $dbh;

exit( $exit > 126 ? 126 : $exit );

sub query
{
        my $sth = $_[0]->prepare($_[1]);
        $sth->execute();

        die($_[0]->errstr) if (!$sth);

        return $sth;
}

sub get_row
{
    return $_[0]->fetchrow_arrayref();
}