MapImage.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\types;
 
use pmmp\encoding\ByteBufferReader;
use pmmp\encoding\ByteBufferWriter;
use pmmp\encoding\DataDecodeException;
use pmmp\encoding\VarInt;
use pocketmine\color\Color;
use pocketmine\network\mcpe\protocol\PacketDecodeException;
use pocketmine\utils\Binary;
use function count;
 
final class MapImage{
    //these limits are enforced in the protocol in 1.20.0
    public const MAX_HEIGHT = 128;
    public const MAX_WIDTH = 128;
 
    private int $width;
    private int $height;
    private array $pixels;
    private ?string $encodedPixelCache = null;
 
    public function __construct(array $pixels){
        $rowLength = null;
        foreach($pixels as $row){
            if($rowLength === null){
                $rowLength = count($row);
            }elseif(count($row) !== $rowLength){
                throw new \InvalidArgumentException("All rows must have the same number of pixels");
            }
        }
        if($rowLength === null){
            throw new \InvalidArgumentException("No pixels provided");
        }
        if($rowLength > self::MAX_WIDTH){
            throw new \InvalidArgumentException("Image width must be at most " . self::MAX_WIDTH . " pixels wide");
        }
        if(count($pixels) > self::MAX_HEIGHT){
            throw new \InvalidArgumentException("Image height must be at most " . self::MAX_HEIGHT . " pixels tall");
        }
        $this->height = count($pixels);
        $this->width = $rowLength;
        $this->pixels = $pixels;
    }
 
    public function getWidth() : int{ return $this->width; }
 
    public function getHeight() : int{ return $this->height; }
 
    public function getPixels() : array{ return $this->pixels; }
 
    public function encode(ByteBufferWriter $out) : void{
        if($this->encodedPixelCache === null){
            $serializer = new ByteBufferWriter();
            for($y = 0; $y < $this->height; ++$y){
                for($x = 0; $x < $this->width; ++$x){
                    //if mojang had any sense this would just be a regular LE int
                    VarInt::writeUnsignedInt($serializer, Binary::flipIntEndianness($this->pixels[$y][$x]->toRGBA()));
                }
            }
            $this->encodedPixelCache = $serializer->getData();
        }
 
        $out->writeByteArray($this->encodedPixelCache);
    }
 
    public static function decode(ByteBufferReader $in, int $height, int $width) : self{
        if($width > self::MAX_WIDTH){
            throw new PacketDecodeException("Image width must be at most " . self::MAX_WIDTH . " pixels wide");
        }
        if($height > self::MAX_HEIGHT){
            throw new PacketDecodeException("Image height must be at most " . self::MAX_HEIGHT . " pixels tall");
        }
        $pixels = [];
 
        for($y = 0; $y < $height; ++$y){
            $row = [];
            for($x = 0; $x < $width; ++$x){
                $row[] = Color::fromRGBA(Binary::flipIntEndianness(VarInt::readUnsignedInt($in)));
            }
            $pixels[] = $row;
        }
 
        return new self($pixels);
    }
}