ItemSerializer.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\item;
 
use pocketmine\block\Block;
use pocketmine\block\VanillaBlocks as Blocks;
use pocketmine\data\bedrock\block\BlockStateSerializeException;
use pocketmine\data\bedrock\block\BlockStateSerializer;
use pocketmine\data\bedrock\item\SavedItemData as Data;
use pocketmine\item\CoralFan;
use pocketmine\item\Item;
use pocketmine\item\ItemBlock;
use pocketmine\item\VanillaItems as Items;
use function get_class;
 
final class ItemSerializer{
    private array $itemSerializers = [];
 
    private array $blockItemSerializers = [];
 
    public function __construct(
        private BlockStateSerializer $blockStateSerializer
    ){
        $this->registerSpecialBlockSerializers();
        new ItemSerializerDeserializerRegistrar(null, $this);
    }
 
    public function map(Item $item, \Closure $serializer) : void{
        $index = $item->getTypeId();
        if(isset($this->itemSerializers[$index])){
            throw new \InvalidArgumentException("Item type ID " . $index . " already has a serializer registered");
        }
        $this->itemSerializers[$index] = $serializer;
    }
 
    public function mapBlock(Block $block, \Closure $serializer) : void{
        $index = $block->getTypeId();
        if(isset($this->blockItemSerializers[$index])){
            throw new \InvalidArgumentException("Block type ID " . $index . " already has a serializer registered");
        }
        $this->blockItemSerializers[$index] = $serializer;
    }
 
    public function serializeType(Item $item) : Data{
        if($item->isNull()){
            throw new \InvalidArgumentException("Cannot serialize a null itemstack");
        }
        if($item instanceof ItemBlock){
            $data = $this->serializeBlockItem($item->getBlock());
        }else{
            $index = $item->getTypeId();
 
            $locatedSerializer = $this->itemSerializers[$index] ?? null;
            if($locatedSerializer === null){
                throw new ItemTypeSerializeException("No serializer registered for " . get_class($item) . " ($index) " . $item->getName());
            }
 
            $serializer = $locatedSerializer;
 
            $data = $serializer($item);
        }
 
        $resultTag = $item->getNamedTag();
        if($resultTag->count() > 0){
            $extraTag = $data->getTag();
            if($extraTag !== null){
                $resultTag = $resultTag->merge($extraTag);
            }
            $data = new Data($data->getName(), $data->getMeta(), $data->getBlock(), $resultTag);
        }
 
        return $data;
    }
 
    public function serializeStack(Item $item, ?int $slot = null) : SavedItemStackData{
        return new SavedItemStackData(
            $this->serializeType($item),
            $item->getCount(),
            $slot,
            null,
            [], //we currently represent canDestroy and canPlaceOn via NBT, like PC
            []
        );
    }
 
    private function serializeBlockItem(Block $block) : Data{
        $index = $block->getTypeId();
 
        $locatedSerializer = $this->blockItemSerializers[$index] ?? null;
        if($locatedSerializer !== null){
            $serializer = $locatedSerializer;
            $data = $serializer($block);
        }else{
            $data = $this->standardBlock($block);
        }
 
        return $data;
    }
 
    private function standardBlock(Block $block) : Data{
        try{
            $blockStateData = $this->blockStateSerializer->serialize($block->getStateId());
        }catch(BlockStateSerializeException $e){
            throw new ItemTypeSerializeException($e->getMessage(), 0, $e);
        }
 
        //TODO: this really ought to throw if there's no blockitem ID
        $itemNameId = BlockItemIdMap::getInstance()->lookupItemId($blockStateData->getName()) ?? $blockStateData->getName();
 
        return new Data($itemNameId, 0, $blockStateData);
    }
 
    private function registerSpecialBlockSerializers() : void{
        //these are encoded as regular blocks, but they have to be accounted for explicitly since they don't use ItemBlock
        //Bamboo->getBlock() returns BambooSapling :(
        $this->map(Items::BAMBOO(), fn() => $this->standardBlock(Blocks::BAMBOO()));
        $this->map(Items::CORAL_FAN(), fn(CoralFan $item) => $this->standardBlock($item->getBlock()));
    }
}