<?php
#################################################################################
## GameSpy PHP Masterserver Class v1.1
##
## Written by:
##  Thomas Reiser alias FiRe^
##  <www.mg34.net/code - fire_1@gmx.de>
##
## Orginal code by:
##  Luigi Auriemma
##  <aluigi.altervista.org - aluigi@autistici.org>
##
## LICENSE:
##  This program is free software; you can redistribute it and/or modify
##  it under the terms of the GNU General Public License as published by
##  the Free Software Foundation; either version 2 of the License, or
##  (at your option) any later version.
##
##  This program is distributed in the hope that it will be useful,
##  but WITHOUT ANY WARRANTY; without even the implied warranty of
##  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
##  GNU General Public License for more details.
##
##  You should have received a copy of the GNU General Public License
##  along with this program; if not, write to the Free Software
##  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
##
##  http://www.gnu.org/licenses/gpl.txt
##
## NOTE:
##  Please include our copyrights and a link to this source file
##  to your website! Thank you.
#################################################################################

class GameSpy {
    var $Host;
    var $Port;
    var $Sock;

    function GameSpy($Host = "master.gamespy.com", $Port = 28900) {
        /*
            --Constructor--
            $Host: GameSpy-Master IP
            $Port: GameSpy-Master Port
        */
        $this->Host = $Host;
        $this->Port = $Port;
    }

    function GetServers($Gamename, $Handoff, $Filter = "") {
        /*
            This function will return the Serverlist for $Gamename in an Array.
            $Gamename: (http://motd.gamespy.com/software/services/index.aspx)
            $Handoff: (http://motd.gamespy.com/software/services/index.aspx?mode=full&services=$Gamename)
                      If the Handoff is >= 13 chars, it will be sized to an 6-char Handoff
            $Filter: The GS-Filter

            Example:
            Array
                (
                        [0] => Array
                        (
                            [ip] => 69.44.61.202
                            [port] => 23000
                        )
                        [1] => Array
                        (
                            [ip] => 195.140.135.250
                            [port] => 23000
                        )
                        ...
                )
        */

        // Try to connect to the GameSpy-Master:
        $this->Sock = @fsockopen("tcp://$this->Host", $this->Port, &$errno, &$errstr, 6);
        @stream_set_timeout($this->Sock, 6);

        if(!$this->Sock) { // Error while connecting
            return false; // :-(
        } else {
            $this->Connected = true;
        }

        // Receive the Secure-Key:
        $SecureKey = substr(fgets($this->Sock, 256), -7, 6);

        // Create the Validate-Key:
        $ValidateKey = $this->__MakeValidate($SecureKey, $Handoff);

        // Send the packet
        $Packet = "\\gamename\\$Gamename\\enctype\\0\\validate\\$ValidateKey\\final\\" .
                  "\\queryid\\1.1\\list\\cmp\\gamename\\$Gamename\\where\\$Filter\\final\\";
        fwrite($this->Sock, $Packet);

        // Receive the (compressed) Serverlist:
        $Data = "";
        do {
            $Data .= fgets($this->Sock, 2048);
            $Buffer = socket_get_status($this->Sock);
        } while($Buffer["unread_bytes"] > 0);

        fclose($this->Sock); // Close socket

        return $this->__ParseCompressedIPs($Data); // Return the parsed Serverlist
    }

    function __ParseCompressedIPs($Data) {
        /*
            Parse the 6-Byte-IP packet and return the Serverlist-Array
            $Data: Compressed IPs received from the Server
        */

        $UnComp = array();
        $i = 0;
        $c = 0;

        // Remove the "\final\":
        $Data = str_replace("\\final\\", "", $Data);

        while($i <= strlen($Data) - 6) {
            // IP
            $UnComp[$c]["ip"] = ord($Data{$i++}).".".ord($Data{$i++}).".".ord($Data{$i++}).".".ord($Data{$i++});
            // Port
            $UnComp[$c++]["port"] = (ord($Data{$i++}) * 256) + ord($Data{$i++});
        }
        
        return $UnComp;
    }

    function __MakeValidate($SecureKey, $Handoff) {
        /*
            MakeValidate creates a Validate-Key for you :D
            $SecureKey: The Secure-Key received from the GS Master
            $Handoff: See GetServers()
        */

        $Temp = array(0, 0, 0, 0, $Handoff); // Array for some temporary Variables
        $Table = array();

        for($i = 0; $i <= 255; $i++) {
            $Table[$i] = $i; // Fill the buffer
        }

        // Check the Handoff-Length:
        if(strlen($Handoff) >= 13) {
            $Handoff = "";
            // Invalid Handoff! -> Need 6-char Handoff
            for($i = 2; $i <= 13; $i += 2) {
                $Handoff .= $Temp[4]{$i};
            }
        }

        // Add the length of the Keys to the array:
        $Length = array(strlen($Handoff), strlen($SecureKey));

        for($i = 0; $i <= 255; $i++) {
            // Scramble the Table with the Handoff:
            $Temp[0] = ($Temp[0] + $Table[$i] + ord($Handoff{$i % $Length[0]})) & 255;
            $Temp[1] = $Table[$Temp[0]];

            // Update the buffer:
            $Table[$Temp[0]] = $Table[$i];
            $Table[$i] = $Temp[1];
        }

        $Temp[0] = 0;
        $Key = array();

        // Scramble the SecureKey with the Table:
        for($i = 0; $i < $Length[1]; $i++) {
            // Add the next char to the Array
            $Key[$i] = ord($SecureKey{$i});

            $Temp[0] = ($Temp[0] + $Key[$i] + 1) & 255;
            $Temp[1] = $Table[$Temp[0]];
            $Temp[2] = ($Temp[2] + $Temp[1]) & 255;
            $Temp[3] = $Table[$Temp[2]];

            $Table[$Temp[2]] = $Temp[1];
            $Table[$Temp[0]] = $Temp[3];

            // XOR the Key with the Buffer:
            $Key[$i] ^= $Table[($Temp[1] + $Temp[3]) & 255];
        }

        $Length[1] /= 3;
        $i = 0;
        $ValidateKey = "";

        // Create the ValidateKey:
        while($Length[1]--) {
            $Temp[1] = $Key[$i++];
            $Temp[3] = $Key[$i++];

            $ValidateKey .= $this->__AddChar($Temp[1] >> 2);
            $ValidateKey .= $this->__AddChar((($Temp[1] & 3) << 4) | ($Temp[3] >> 4));

            $Temp[1] = $Key[$i++];

            $ValidateKey .= $this->__AddChar((($Temp[3] & 15) << 2) | ($Temp[1] >> 6));
            $ValidateKey .= $this->__AddChar($Temp[1] & 63);
        }

        return $ValidateKey;
    }

    function __AddChar($Number) {
        // Return a new char
        if($Number < 26) {
            return chr($Number + 65);
        } elseif($Number < 52) {
            return chr($Number + 71);
        } elseif($Number < 62) {
            return chr($Number - 4);
        } elseif($Number == 62) {
            return "+";
        } elseif($Number == 63) {
            return "/";
        }
    }
}
?>