BedrockProtocol/tools/generate-protocol-info.php

<?php

/*
 * This file is part of BedrockProtocol.
 * Copyright (C) 2014-2022 PocketMine Team <https://github.com/pmmp/BedrockProtocol>
 *
 * BedrockProtocol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 */

declare(strict_types=1);

namespace pocketmine\network\mcpe\protocol\tools\generate_protocol_info;

use pocketmine\network\mcpe\protocol\ClientboundPacket;
use pocketmine\network\mcpe\protocol\DataPacket;
use pocketmine\network\mcpe\protocol\Packet;
use pocketmine\network\mcpe\protocol\PacketDecodeException;
use pocketmine\network\mcpe\protocol\PacketHandlerDefaultImplTrait;
use pocketmine\network\mcpe\protocol\PacketHandlerInterface;
use pocketmine\network\mcpe\protocol\PacketPool;
use pocketmine\network\mcpe\protocol\ServerboundPacket;
use function array_fill_keys;
use function asort;
use function ceil;
use function count;
use function dechex;
use function dirname;
use function file_exists;
use function file_get_contents;
use function file_put_contents;
use function fwrite;
use function implode;
use function is_array;
use function is_bool;
use function is_int;
use function is_string;
use function json_decode;
use function max;
use function preg_split;
use function scandir;
use function sprintf;
use function str_contains;
use function str_ends_with;
use function str_pad;
use function strlen;
use function strtoupper;
use function substr;
use const DIRECTORY_SEPARATOR;
use const JSON_THROW_ON_ERROR;
use const PHP_EOL;
use const PREG_SPLIT_DELIM_CAPTURE;
use const PREG_SPLIT_NO_EMPTY;
use const SORT_NUMERIC;
use const STDERR;
use const STR_PAD_LEFT;

const DATA_PACKET_TEMPLATE = <<<'CODE'
<?php

/*
 * This file is part of BedrockProtocol.
 * Copyright (C) 2014-2022 PocketMine Team <https://github.com/pmmp/BedrockProtocol>
 *
 * BedrockProtocol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 */

declare(strict_types=1);

namespace pocketmine\network\mcpe\protocol;

use pocketmine\network\mcpe\protocol\serializer\PacketSerializer;

class %s extends DataPacket{
	public const NETWORK_ID = ProtocolInfo::%s;

	/**
	 * @generate-create-func
	 */
	public static function create() : self{
		$result = new self;
		//TODO: add fields
		return $result;
	}

	protected function decodePayload(PacketSerializer $in) : void{
		//TODO
	}

	protected function encodePayload(PacketSerializer $out) : void{
		//TODO
	}

	public function handle(PacketHandlerInterface $handler) : bool{
		return $handler->handle%s($this);
	}
}

CODE;

const PACKET_HANDLER_TRAIT_TEMPLATE = <<<'CODE'
<?php

/*
 * This file is part of BedrockProtocol.
 * Copyright (C) 2014-2022 PocketMine Team <https://github.com/pmmp/BedrockProtocol>
 *
 * BedrockProtocol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 */

declare(strict_types=1);

namespace pocketmine\network\mcpe\protocol;

/**
 * This trait provides default implementations for all packet handlers, so that you don't have to manually write
 * handlers for every single packet even if you don't care about them.
 *
 * This file is automatically generated. Do not edit it manually.
 */
trait PacketHandlerDefaultImplTrait{

%s
}

CODE;

const PACKET_HANDLER_INTERFACE_TEMPLATE = <<<'CODE'
<?php

/*
 * This file is part of BedrockProtocol.
 * Copyright (C) 2014-2022 PocketMine Team <https://github.com/pmmp/BedrockProtocol>
 *
 * BedrockProtocol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 */

declare(strict_types=1);

namespace pocketmine\network\mcpe\protocol;

/**
 * This class is an automatically generated stub. Do not edit it manually.
 */
interface PacketHandlerInterface{
%s
}

CODE;

const PACKET_POOL_TEMPLATE = <<<'CODE'
<?php

/*
 * This file is part of BedrockProtocol.
 * Copyright (C) 2014-2022 PocketMine Team <https://github.com/pmmp/BedrockProtocol>
 *
 * BedrockProtocol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 */

declare(strict_types=1);

namespace pocketmine\network\mcpe\protocol;

use pocketmine\utils\Binary;
use pocketmine\utils\BinaryDataException;

class PacketPool{
	protected static ?PacketPool $instance = null;

	public static function getInstance() : self{
		if(self::$instance === null){
			self::$instance = new self;
		}
		return self::$instance;
	}

	/** @var \SplFixedArray<Packet> */
	protected \SplFixedArray $pool;

	public function __construct(){
		$this->pool = new \SplFixedArray(%d);
%s
	}

	public function registerPacket(Packet $packet) : void{
		$this->pool[$packet->pid()] = clone $packet;
	}

	public function getPacketById(int $pid) : ?Packet{
		return isset($this->pool[$pid]) ? clone $this->pool[$pid] : null;
	}

	/**
	 * @throws BinaryDataException
	 */
	public function getPacket(string $buffer) : ?Packet{
		$offset = 0;
		return $this->getPacketById(Binary::readUnsignedVarInt($buffer, $offset) & DataPacket::PID_MASK);
	}
}

CODE;

const PROTOCOL_INFO_TEMPLATE = <<<'CODE'
<?php

/*
 * This file is part of BedrockProtocol.
 * Copyright (C) 2014-2022 PocketMine Team <https://github.com/pmmp/BedrockProtocol>
 *
 * BedrockProtocol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 */

declare(strict_types=1);

namespace pocketmine\network\mcpe\protocol;

/**
 * Version numbers and packet IDs for the current Minecraft PE protocol
 */
final class ProtocolInfo{

	private function __construct(){
		//NOOP
	}

	/**
	 * NOTE TO DEVELOPERS
	 * Do not waste your time or ours submitting pull requests changing game and/or protocol version numbers.
	 * Pull requests changing game and/or protocol version numbers will be closed.
	 *
	 * This file is generated automatically, do not edit it manually.
	 */

	/** Actual Minecraft: PE protocol version */
	public const CURRENT_PROTOCOL = %d;
	/** Current Minecraft PE version reported by the server. This is usually the earliest currently supported version. */
	public const MINECRAFT_VERSION = '%s';
	/** Version number sent to clients in ping responses. */
	public const MINECRAFT_VERSION_NETWORK = '%s';

%s
}

CODE;

/**
 * @return string[]
 */
function split_upper(string $string) : array{
	$split = preg_split('/([A-Z][^A-Z]*)/', $string, flags: PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY);
	if($split === false){
		throw new \Error("preg_split failed");
	}
	return $split;
}

function rchop(string $string, string $substring) : string{
	if(str_ends_with($string, $substring)){
		return substr($string, 0, -strlen($substring));
	}
	return $string;
}

/**
 * @param string[] $packetToIdList
 * @phpstan-param array<string, int> $packetToIdList
 */
function generate_new_packet_stubs(array $packetToIdList, string $packetsDir) : void{
	foreach($packetToIdList as $name => $id){
		$packetFilePath = $packetsDir . DIRECTORY_SEPARATOR . $name . '.php';
		if(!file_exists($packetFilePath)){
			echo "!!! New packet: $name" . PHP_EOL;
			$constName = strtoupper(implode('_', split_upper($name)));
			$baseName = rchop($name, 'Packet');
			file_put_contents($packetFilePath, sprintf(DATA_PACKET_TEMPLATE, $name, $constName, $baseName));
			echo "Created stub class for $name at $packetFilePath" . PHP_EOL;
		}
	}
}

/**
 * @param string[] $packetToIdList
 * @phpstan-param array<string, int> $packetToIdList
 */
function check_removed_packets(array $packetToIdList, string $packetsDir) : void{
	$existing = scandir($packetsDir);
	if($existing === false){
		return;
	}

	//use ::class constants here so that they are checked for existence
	$ignoredClasses = array_fill_keys([
		DataPacket::class,
		PacketPool::class,
		Packet::class,
		PacketDecodeException::class,
		PacketHandlerDefaultImplTrait::class,
		PacketHandlerInterface::class,
		ClientboundPacket::class,
		ServerboundPacket::class,
	], true);
	foreach($existing as $fileName){
		if(str_ends_with($fileName, ".php")){
			$packetName = substr($fileName, 0, -strlen(".php"));
			if(!str_contains($packetName, "Packet") || isset($ignoredClasses["pocketmine\\network\\mcpe\\protocol\\" . $packetName])){
				continue;
			}
			if(!isset($packetToIdList[$packetName])){
				echo "!!! Removed packet: $packetName" . PHP_EOL;
			}
		}
	}
}

/**
 * @param string[] $packetToIdList
 * @phpstan-param array<string, int> $packetToIdList
 */
function generate_protocol_info(array $packetToIdList, int $protocolVersion, int $major, int $minor, int $patch, int $revision, bool $beta, string $packetsDir) : void{
	$consts = "";
	$last = 0;

	foreach($packetToIdList as $name => $id){
		if($id !== $last + 1){
			$consts .= "\n";
		}

		$last = $id;
		$consts .= sprintf(
			"\tpublic const %s = %s;\n",
			strtoupper(implode("_", split_upper($name))),
			"0x" . str_pad(dechex($id), 2, "0", STR_PAD_LEFT)
		);
	}

	$gameVersion = sprintf("v%d.%d.%d%s", $major, $minor, $patch, $beta ? ".$revision beta" : "");
	$gameVersionNetwork = sprintf("%d.%d.%d%s", $major, $minor, $patch, $beta ? ".$revision" : "");
	file_put_contents($packetsDir . DIRECTORY_SEPARATOR . "ProtocolInfo.php", sprintf(
		PROTOCOL_INFO_TEMPLATE,
		$protocolVersion,
		$gameVersion,
		$gameVersionNetwork,
		$consts
	));

	echo "Recreated ProtocolInfo" . PHP_EOL;
}

/**
 * @param string[] $packetToIdList
 * @phpstan-param array<string, int> $packetToIdList
 */
function generate_packet_pool(array $packetToIdList, string $packetsDir) : void{
	$entries = "";

	foreach($packetToIdList as $name => $id){
		$entries .= sprintf("\n\t\t\$this->registerPacket(new %s());", $name);
	}

	$poolSize = (int) (ceil(max($packetToIdList) / 256) * 256);
	file_put_contents($packetsDir . DIRECTORY_SEPARATOR . "PacketPool.php", sprintf(
		PACKET_POOL_TEMPLATE,
		$poolSize,
		$entries
	));
	echo "Recreated PacketPool\n";
}

/**
 * @param string[] $packetToIdList
 * @phpstan-param array<string, int> $packetToIdList
 */
function generate_packet_handler_classes(array $packetToIdList, string $packetsDir) : void{
	$interfaceFunctions = [];
	$traitFunctions = [];

	foreach($packetToIdList as $name => $id){
		$baseName = rchop($name, "Packet");
		$interfaceFunctions[] = sprintf("\tpublic function handle%s(%s \$packet) : bool;", $baseName, $name);
		$traitFunctions[] = sprintf("\tpublic function handle%s(%s \$packet) : bool{\n\t\treturn false;\n\t}", $baseName, $name);
	}

	file_put_contents($packetsDir . DIRECTORY_SEPARATOR . "PacketHandlerInterface.php", sprintf(
		PACKET_HANDLER_INTERFACE_TEMPLATE,
		implode("\n\n", $interfaceFunctions)
	));
	echo "Recreated PacketHandlerInterface" . PHP_EOL;
	file_put_contents($packetsDir . DIRECTORY_SEPARATOR . "PacketHandlerDefaultImplTrait.php", sprintf(
		PACKET_HANDLER_TRAIT_TEMPLATE,
		implode("\n\n", $traitFunctions)
	));
	echo "Recreated PacketHandlerDefaultImplTrait" . PHP_EOL;
}

if(count($argv) < 2){
	fwrite(STDERR, "Please provide an input protocol_info.json file" . PHP_EOL);
	exit(1);
}

$rawData = file_get_contents($argv[1]);
if($rawData === false){
	fwrite(STDERR, "Couldn't read data from " . $argv[1] . PHP_EOL);
	exit(1);
}

try{
	$json = json_decode($rawData, associative: true, flags: JSON_THROW_ON_ERROR);
}catch(\JsonException $e){
	fwrite(STDERR, "Error decoding input file: " . $e->getMessage() . PHP_EOL);
	exit(1);
}
if(!is_array($json) || count($json) !== 2 || !is_array($json["version"] ?? null) || !is_array($json["packets"] ?? null)){
	fwrite(STDERR, "Invalid input file, expected 2 objects: \"version\" and \"packets\"" . PHP_EOL);
	exit(1);
}

$versionInfo = $json["version"];
$major = $versionInfo["major"] ?? null;
$minor = $versionInfo["minor"] ?? null;
$patch = $versionInfo["patch"] ?? null;
$revision = $versionInfo["revision"] ?? null;
$beta = $versionInfo["beta"] ?? null;
$protocolVersion = $versionInfo["protocol_version"] ?? null;
if(!is_int($major) || !is_int($minor) || !is_int($patch) || !is_int($revision) || !is_bool($beta) || !is_int($protocolVersion)){
	fwrite(STDERR, "Invalid version info, expected \"major\" (int), \"minor\" (int), \"patch\" (int), \"revision\" (int), \"beta\" (bool) and \"protocol_version\" (int)" . PHP_EOL);
	exit(1);
}

echo "Generating code basics for version $major.$minor.$patch.$revision " . ($beta ? "beta" : "") . " (protocol $protocolVersion)" . PHP_EOL;

$packetToIdList = [];
foreach($json["packets"] as $name => $id){
	if(!is_string($name) || !is_int($id)){
		fwrite(STDERR, "Invalid packet entry \"$name\", expected string => int" . PHP_EOL);
		exit(1);
	}
	$packetToIdList[$name] = $id;
}
asort($packetToIdList, SORT_NUMERIC);

$packetsDir = dirname(__DIR__) . '/src/';
generate_protocol_info($packetToIdList, $protocolVersion, $major, $minor, $patch, $revision, $beta, $packetsDir);
generate_packet_pool($packetToIdList, $packetsDir);
generate_packet_handler_classes($packetToIdList, $packetsDir);
check_removed_packets($packetToIdList, $packetsDir);
generate_new_packet_stubs($packetToIdList, $packetsDir);

echo "Done" . PHP_EOL;