<?php
class MinecraftQueryException extends Exception
{
// Exception thrown by MinecraftQuery class
}

class MinecraftQuery
{
/*
* Class written by xPaw
*
* Website: http://xpaw.ru
* GitHub: https://github.com/xPaw/PHP-Minecraft-Query
*/

const STATISTIC = 0x00;
const HANDSHAKE = 0x09;

private $Socket;
private $Players;
private $Info;

public function Connect( $Ip, $Port = 25565, $Timeout = 3 )
{
if( !is_int( $Timeout ) || $Timeout < 0 )
{
throw new InvalidArgumentException( 'Timeout must be an integer.' );
}

$this->Socket = @FSockOpen( 'udp://' . $Ip, (int)$Port, $ErrNo, $ErrStr, $Timeout );

if( $ErrNo || $this->Socket === false )
{
throw new MinecraftQueryException( 'Could not create socket: ' . $ErrStr );
}

Stream_Set_Timeout( $this->Socket, $Timeout );
Stream_Set_Blocking( $this->Socket, true );

try
{
$Challenge = $this->GetChallenge( );

$this->GetStatus( $Challenge );
}
// We catch this because we want to close the socket, not very elegant
catch( MinecraftQueryException $e )
{
FClose( $this->Socket );

throw new MinecraftQueryException( $e->getMessage( ) );
}

FClose( $this->Socket );
}

public function GetInfo( )
{
return isset( $this->Info ) ? $this->Info : false;
}

public function GetPlayers( )
{
return isset( $this->Players ) ? $this->Players : false;
}

private function GetChallenge( )
{
$Data = $this->WriteData( self :: HANDSHAKE );

if( $Data === false )
{
throw new MinecraftQueryException( "Failed to receive challenge." );
}

return Pack( 'N', $Data );
}

private function GetStatus( $Challenge )
{
$Data = $this->WriteData( self :: STATISTIC, $Challenge . Pack( 'c*', 0x00, 0x00, 0x00, 0x00 ) );

if( !$Data )
{
throw new MinecraftQueryException( "Failed to receive status." );
}

$Last = "";
$Info = Array( );

$Data = SubStr( $Data, 11 ); // splitnum + 2 int
$Data = Explode( "\x00\x00\x01player_\x00\x00", $Data );
$Players = SubStr( $Data[ 1 ], 0, -2 );
$Data = Explode( "\x00", $Data[ 0 ] );

// Array with known keys in order to validate the result
// It can happen that server sends custom strings containing bad things (who can know!)
$Keys = Array(
'hostname' => 'HostName',
'gametype' => 'GameType',
'version' => 'Version',
'plugins' => 'Plugins',
'map' => 'Map',
'numplayers' => 'Players',
'maxplayers' => 'MaxPlayers',
'hostport' => 'HostPort',
'hostip' => 'HostIp'
);

foreach( $Data as $Key => $Value )
{
if( ~$Key & 1 )
{
if( !Array_Key_Exists( $Value, $Keys ) )
{
$Last = false;
continue;
}

$Last = $Keys[ $Value ];
$Info[ $Last ] = "";
}
else if( $Last != false )
{
$Info[ $Last ] = $Value;
}
}

// Ints
$Info[ 'Players' ] = IntVal( $Info[ 'Players' ] );
$Info[ 'MaxPlayers' ] = IntVal( $Info[ 'MaxPlayers' ] );
$Info[ 'HostPort' ] = IntVal( $Info[ 'HostPort' ] );

// Parse "plugins", if any
if( $Info[ 'Plugins' ] )
{
$Data = Explode( ": ", $Info[ 'Plugins' ], 2 );

$Info[ 'RawPlugins' ] = $Info[ 'Plugins' ];
$Info[ 'Software' ] = $Data[ 0 ];

if( Count( $Data ) == 2 )
{
$Info[ 'Plugins' ] = Explode( "; ", $Data[ 1 ] );
}
}
else
{
$Info[ 'Software' ] = 'Vanilla';
}

$this->Info = $Info;

if( $Players )
{
$this->Players = Explode( "\x00", $Players );
}
}

private function WriteData( $Command, $Append = "" )
{
$Command = Pack( 'c*', 0xFE, 0xFD, $Command, 0x01, 0x02, 0x03, 0x04 ) . $Append;
$Length = StrLen( $Command );

if( $Length !== FWrite( $this->Socket, $Command, $Length ) )
{
throw new MinecraftQueryException( "Failed to write on socket." );
}

$Data = FRead( $this->Socket, 2048 );

if( $Data === false )
{
throw new MinecraftQueryException( "Failed to read from socket." );
}

if( StrLen( $Data ) < 5 || $Data[ 0 ] != $Command[ 2 ] )
{
return false;
}

return SubStr( $Data, 5 );
}
}