@loaders.gl/i3s/dist/lib/parsers/parse-slpk/parse-slpk.js

i3s .

import { parseZipCDFileHeader, CD_HEADER_SIGNATURE, parseZipLocalFileHeader, searchFromTheEnd, parseHashTable, makeHashTableFromZipHeaders } from '@loaders.gl/zip';
import { SLPKArchive } from "./slpk-archieve.js";
/**
 * Creates slpk file handler from raw file
 * @param fileProvider raw file data
 * @param cb is called with information message during parsing
 * @returns slpk file handler
 */
export async function parseSLPKArchive(fileProvider, cb, fileName) {
    const hashCDOffset = await searchFromTheEnd(fileProvider, CD_HEADER_SIGNATURE);
    const cdFileHeader = await parseZipCDFileHeader(hashCDOffset, fileProvider);
    let hashTable;
    if (cdFileHeader?.fileName !== '@specialIndexFileHASH128@') {
        hashTable = await makeHashTableFromZipHeaders(fileProvider);
        cb?.('SLPK doesnt contain hash file, hash info has been composed according to zip archive headers');
    }
    else {
        // cb?.('SLPK contains hash file');
        const localFileHeader = await parseZipLocalFileHeader(cdFileHeader.localHeaderOffset, fileProvider);
        if (!localFileHeader) {
            throw new Error('corrupted SLPK');
        }
        const fileDataOffset = localFileHeader.fileDataOffset;
        const hashFile = await fileProvider.slice(fileDataOffset, fileDataOffset + localFileHeader.compressedSize);
        hashTable = parseHashTable(hashFile);
    }
    return new SLPKArchive(fileProvider, hashTable, fileName);
}