<?php

class SampQueryAPI
{
    private $rSocket = false;
    private $aServer = array();

    public function __construct($sServer, $iPort = 7777)
    {
        $this->aServer[0] = $sServer;
        $this->aServer[1] = $iPort;

        $this->rSocket = fsockopen('udp://'.$this->aServer[0], $this->aServer[1], $iError, $sError, 2);

        if(!$this->rSocket)
        {
            $this->aServer[4] = false;
            return;
        }

        socket_set_timeout($this->rSocket, 2);

        $sPacket = 'SAMP';
        $sPacket .= chr(strtok($this->aServer[0], '.'));
        $sPacket .= chr(strtok('.'));
        $sPacket .= chr(strtok('.'));
        $sPacket .= chr(strtok('.'));
        $sPacket .= chr($this->aServer[1] & 0xFF);
        $sPacket .= chr($this->aServer[1] >> 8 & 0xFF);
        $sPacket .= 'p4150';

        fwrite($this->rSocket, $sPacket);

        if(fread($this->rSocket, 10))
        {
            if(fread($this->rSocket, 5) == 'p4150')
            {
                $this->aServer[4] = true;
                return;
            }
        }

        $this->aServer[4] = false;
    }


    public function __destruct()
    {
        @fclose($this->rSocket);
    }

    public function isOnline()
    {
        return isset($this->aServer[4]) ? $this->aServer[4] : false;
    }

    public function getInfo()
    {
        @fwrite($this->rSocket, $this->createPacket('i'));

        fread($this->rSocket, 11);

        $aDetails['password'] = (integer) ord(fread($this->rSocket, 1));

        $aDetails['players'] = (integer) $this->toInteger(fread($this->rSocket, 2));

        $aDetails['maxplayers'] = (integer) $this->toInteger(fread($this->rSocket, 2));

        $iStrlen = ord(fread($this->rSocket, 4));
        if(!$iStrlen) return -1;

        $aDetails['hostname'] = (string) fread($this->rSocket, $iStrlen);

        $iStrlen = ord(fread($this->rSocket, 4));
        $aDetails['gamemode'] = (string) fread($this->rSocket, $iStrlen);

        $iStrlen = ord(fread($this->rSocket, 4));
        $aDetails['mapname'] = (string) fread($this->rSocket, $iStrlen);

        return $aDetails;
    }

    public function getBasicPlayers()
    {
        @fwrite($this->rSocket, $this->createPacket('c'));
        fread($this->rSocket, 11);

        $iPlayerCount = ord(fread($this->rSocket, 2));
        $aDetails = array();

        if($iPlayerCount > 0)
        {
            for($iIndex = 0; $iIndex < $iPlayerCount; ++$iIndex)
            {
                $iStrlen = ord(fread($this->rSocket, 1));
                $aDetails[] = array
                (
                    "nickname" => (string) fread($this->rSocket, $iStrlen),
                    "score" => (integer) $this->toInteger(fread($this->rSocket, 4)),
                );
            }
        }

        return $aDetails;
    }

    public function getDetailedPlayers()
    {
        @fwrite($this->rSocket, $this->createPacket('d'));
        fread($this->rSocket, 11);

        $iPlayerCount = ord(fread($this->rSocket, 2));
        $aDetails = array();

        for($iIndex = 0; $iIndex < $iPlayerCount; ++$iIndex)
        {
            $aPlayer['playerid'] = (integer) ord(fread($this->rSocket, 1));

            $iStrlen = ord(fread($this->rSocket, 1));
            $aPlayer['nickname'] = (string) fread($this->rSocket, $iStrlen);

            $aPlayer['score'] = (integer) $this->toInteger(fread($this->rSocket, 4));
            $aPlayer['ping'] = (integer) $this->toInteger(fread($this->rSocket, 4));

            $aDetails[] = $aPlayer;
            unset($aPlayer);
        }

        return $aDetails;
    }

    public function getRules()
    {
        @fwrite($this->rSocket, $this->createPacket('r'));
        fread($this->rSocket, 11);

        $iRuleCount = ord(fread($this->rSocket, 2));
        $aReturn = array();

        for($iIndex = 0; $iIndex < $iRuleCount; ++$iIndex)
        {
            $iStrlen = ord(fread($this->rSocket, 1));
            $sRulename = (string) fread($this->rSocket, $iStrlen);

            $iStrlen = ord(fread($this->rSocket, 1));
            $aDetails[$sRulename] = (string) fread($this->rSocket, $iStrlen);
        }

        return $aDetails;
    }


    private function toInteger($sData)
    {
        if($sData === "")
        {
            return null;
        }

        $iInteger = 0;
        $iInteger += (ord($sData[0]));

        if(isset($sData[1]))
        {
            $iInteger += (ord($sData[1]) << 8);
        }

        if(isset($sData[2]))
        {
            $iInteger += (ord($sData[2]) << 16);
        }

        if(isset($sData[3]))
        {
            $iInteger += (ord($sData[3]) << 24);
        }

        if($iInteger >= 4294967294)
        {
            $iInteger -= 4294967296;
        }

        return $iInteger;
    }


    private function createPacket($sPayload)
    {
        $sPacket = 'SAMP';
        $sPacket .= chr(strtok($this->aServer[0], '.'));
        $sPacket .= chr(strtok('.'));
        $sPacket .= chr(strtok('.'));
        $sPacket .= chr(strtok('.'));
        $sPacket .= chr($this->aServer[1] & 0xFF);
        $sPacket .= chr($this->aServer[1] >> 8 & 0xFF);
        $sPacket .= $sPayload;

        return $sPacket;
    }
}

function getServerInfoJSON($serverIP, $serverPort, $useJsonUI) {
    $q = new SampQueryAPI($serverIP, $serverPort);
    $aInformation = $q->getInfo();
    $aServerRules = $q->getRules();

    $data = array(
        'hostname' => htmlentities($aInformation['hostname']),
        'gamemode' => htmlentities($aInformation['gamemode']),
        'players' => $aInformation['players'],
        'maxplayers' => $aInformation['maxplayers'],
        'mapname' => htmlentities($aInformation['mapname']),
        'weather' => $aServerRules['weather'],
        'time' => $aServerRules['worldtime'],
        'version' => $aServerRules['version'],
        'password' => $aInformation['password'] ? 'Yes' : 'No'
    );

    if($useJsonUI) {
        header('Content-Type: application/json');
    }

    return json_encode($data);
}

$serverIP = $_GET['server_ip'] ?? '';
$serverPort = $_GET['server_port'] ?? '';
$useUI = $_GET['ui'] ?? '';

if(isset($serverIP) && isset($serverPort)) {
    if(isset($useUI)) {
        echo getServerInfoJSON($serverIP, $serverPort, $useUI == 'true' ? true : false);
    } else {
        echo getServerInfoJSON($serverIP, $serverPort, false);
    }
}