ZippedResourcePack.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\resourcepacks;
 
use Ahc\Json\Comment as CommentedJsonDecoder;
use pocketmine\resourcepacks\json\Manifest;
use pocketmine\utils\Utils;
use function assert;
use function fclose;
use function feof;
use function file_exists;
use function filesize;
use function fopen;
use function fread;
use function fseek;
use function gettype;
use function hash_file;
use function implode;
use function preg_match;
use function strlen;
 
class ZippedResourcePack implements ResourcePack{
    protected string $path;
    protected Manifest $manifest;
    protected ?string $sha256 = null;
 
    protected $fileResource;
 
    public function __construct(string $zipPath){
        $this->path = $zipPath;
 
        if(!file_exists($zipPath)){
            throw new ResourcePackException("File not found");
        }
        $size = filesize($zipPath);
        if($size === false){
            throw new ResourcePackException("Unable to determine size of file");
        }
        if($size === 0){
            throw new ResourcePackException("Empty file, probably corrupted");
        }
 
        $archive = new \ZipArchive();
        if(($openResult = $archive->open($zipPath)) !== true){
            throw new ResourcePackException("Encountered ZipArchive error code $openResult while trying to open $zipPath");
        }
 
        if(($manifestData = $archive->getFromName("manifest.json")) === false){
            $manifestPath = null;
            $manifestIdx = null;
            for($i = 0; $i < $archive->numFiles; ++$i){
                $name = Utils::assumeNotFalse($archive->getNameIndex($i), "This index should be valid");
                if(
                    ($manifestPath === null || strlen($name) < strlen($manifestPath)) &&
                    preg_match('#.*/manifest.json$#', $name) === 1
                ){
                    $manifestPath = $name;
                    $manifestIdx = $i;
                }
            }
            if($manifestIdx !== null){
                $manifestData = $archive->getFromIndex($manifestIdx);
                assert($manifestData !== false);
            }elseif($archive->locateName("pack_manifest.json") !== false){
                throw new ResourcePackException("Unsupported old pack format");
            }else{
                throw new ResourcePackException("manifest.json not found in the archive root");
            }
        }
 
        $archive->close();
 
        //maybe comments in the json, use stripped decoder (thanks mojang)
        try{
            $manifest = (new CommentedJsonDecoder())->decode($manifestData);
        }catch(\RuntimeException $e){
            throw new ResourcePackException("Failed to parse manifest.json: " . $e->getMessage(), 0, $e);
        }
        if(!($manifest instanceof \stdClass)){
            throw new ResourcePackException("manifest.json should contain a JSON object, not " . gettype($manifest));
        }
 
        $mapper = new \JsonMapper();
        $mapper->bExceptionOnMissingData = true;
        $mapper->bStrictObjectTypeChecking = true;
 
        try{
            $manifest = $mapper->map($manifest, new Manifest());
        }catch(\JsonMapper_Exception $e){
            throw new ResourcePackException("Invalid manifest.json contents: " . $e->getMessage(), 0, $e);
        }
 
        $this->manifest = $manifest;
 
        $this->fileResource = fopen($zipPath, "rb");
    }
 
    public function __destruct(){
        fclose($this->fileResource);
    }
 
    public function getPath() : string{
        return $this->path;
    }
 
    public function getPackName() : string{
        return $this->manifest->header->name;
    }
 
    public function getPackVersion() : string{
        return implode(".", $this->manifest->header->version);
    }
 
    public function getPackId() : string{
        return $this->manifest->header->uuid;
    }
 
    public function getPackSize() : int{
        return filesize($this->path);
    }
 
    public function getSha256(bool $cached = true) : string{
        if($this->sha256 === null || !$cached){
            $this->sha256 = hash_file("sha256", $this->path, true);
        }
        return $this->sha256;
    }
 
    public function getPackChunk(int $start, int $length) : string{
        if($length < 1){
            throw new \InvalidArgumentException("Pack length must be positive");
        }
        fseek($this->fileResource, $start);
        if(feof($this->fileResource)){
            throw new \InvalidArgumentException("Requested a resource pack chunk with invalid start offset");
        }
        return Utils::assumeNotFalse(fread($this->fileResource, $length), "Already checked that we're not at EOF");
    }
}