BlockIdMetaUpgrader.php

<?php
 
/*
 *
 *  ____            _        _   __  __ _                  __  __ ____
 * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
 * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
 * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
 * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
 *
 * This program 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.
 *
 * @author PocketMine Team
 * @link http://www.pocketmine.net/
 *
 *
 */
 
declare(strict_types=1);
 
namespace pocketmine\data\bedrock\block\upgrade;
 
use pmmp\encoding\ByteBufferReader;
use pmmp\encoding\DataDecodeException;
use pmmp\encoding\VarInt;
use pocketmine\data\bedrock\block\BlockStateData;
use pocketmine\data\bedrock\block\BlockStateDeserializeException;
use pocketmine\nbt\LittleEndianNbtSerializer;
 
final class BlockIdMetaUpgrader{
    public function __construct(
        private array $mappingTable,
        private LegacyBlockIdToStringIdMap $legacyNumericIdMap
    ){}
 
    public function fromStringIdMeta(string $id, int $meta) : BlockStateData{
        return $this->mappingTable[$id][$meta] ??
            $this->mappingTable[$id][0] ??
            throw new BlockStateDeserializeException("Unknown legacy block string ID $id");
    }
 
    public function fromIntIdMeta(int $id, int $meta) : BlockStateData{
        $stringId = $this->legacyNumericIdMap->legacyToString($id);
        if($stringId === null){
            throw new BlockStateDeserializeException("Unknown legacy block numeric ID $id");
        }
        return $this->fromStringIdMeta($stringId, $meta);
    }
 
    public function addIntIdToStringIdMapping(int $intId, string $stringId) : void{
        $this->legacyNumericIdMap->add($stringId, $intId);
    }
 
    public function addIdMetaToStateMapping(string $stringId, int $meta, BlockStateData $stateData) : void{
        if(isset($this->mappingTable[$stringId][$meta])){
            throw new \InvalidArgumentException("A mapping for $stringId:$meta already exists");
        }
        $this->mappingTable[$stringId][$meta] = $stateData;
    }
 
    public static function loadFromString(string $data, LegacyBlockIdToStringIdMap $idMap, BlockStateUpgrader $blockStateUpgrader) : self{
        $mappingTable = [];
 
        $legacyStateMapReader = new ByteBufferReader($data);
        $nbtReader = new LittleEndianNbtSerializer();
 
        $idCount = VarInt::readUnsignedInt($legacyStateMapReader);
        for($idIndex = 0; $idIndex < $idCount; $idIndex++){
            $id = $legacyStateMapReader->readByteArray(VarInt::readUnsignedInt($legacyStateMapReader));
 
            $metaCount = VarInt::readUnsignedInt($legacyStateMapReader);
            for($metaIndex = 0; $metaIndex < $metaCount; $metaIndex++){
                $meta = VarInt::readUnsignedInt($legacyStateMapReader);
 
                $offset = $legacyStateMapReader->getOffset();
                $state = $nbtReader->read($legacyStateMapReader->getData(), $offset)->mustGetCompoundTag();
                $legacyStateMapReader->setOffset($offset);
                $mappingTable[$id][$meta] = $blockStateUpgrader->upgrade(BlockStateData::fromNbt($state));
            }
        }
        if($legacyStateMapReader->getUnreadLength() > 0){
            throw new DataDecodeException("Unexpected trailing data in legacy state map data");
        }
 
        return new self($mappingTable, $idMap);
    }
}