igir/dist/packages/zip/src/fileRecord.js

🕹 A zero-setup ROM collection manager that sorts, filters, extracts or archives, patches, and reports on collections of any size on any OS.

import CP437Decoder from './cp437Decoder.js';
import TimestampUtil from './timestampUtil.js';
export const CompressionMethod = {
    STORE: 0,
    SHRUNK: 1,
    REDUCED_FACTOR_1: 2,
    REDUCED_FACTOR_2: 3,
    REDUCED_FACTOR_3: 4,
    REDUCED_FACTOR_4: 5,
    IMPLODE: 6,
    DEFLATE: 8,
    DEFLATE64: 9,
    PKWARE_IMPLODE: 10,
    BZIP2: 12,
    LZMA: 14,
    IBM_CMPSC: 16,
    IBM_TERSE: 18,
    IBM_LZ77: 19,
    ZSTD_DEPRECATED: 20,
    ZSTD: 93,
    MP3: 94,
    XZ: 95,
    JPEG_VARIANT: 96,
    WAVPACK: 97,
    PPMD: 98,
    AE_X: 99,
};
export const CompressionMethodInverted = Object.fromEntries(Object.entries(CompressionMethod).map(([key, value]) => [value, key]));
/**
 * A zip file record, with properties and functionality common to local file headers and central
 * directory file headers.
 */
export default class FileRecord {
    raw;
    versionNeeded;
    generalPurposeBitFlag;
    compressionMethod;
    fileModificationTime;
    fileModificationDate;
    uncompressedCrc32;
    compressedSize;
    uncompressedSize;
    fileNameLength;
    extraFieldLength;
    fileName;
    extraFields;
    zip64ExtendedInformation;
    constructor(props) {
        this.raw = props.raw;
        this.versionNeeded = props.versionNeeded;
        this.generalPurposeBitFlag = props.generalPurposeBitFlag;
        this.compressionMethod = props.compressionMethod;
        this.fileModificationTime = props.fileModificationTime;
        this.fileModificationDate = props.fileModificationDate;
        this.uncompressedCrc32 = props.uncompressedCrc32;
        this.compressedSize = props.compressedSize;
        this.uncompressedSize = props.uncompressedSize;
        this.fileNameLength = props.fileNameLength;
        this.extraFieldLength = props.extraFieldLength;
        this.fileName = props.fileName;
        this.extraFields = props.extraFields;
        this.zip64ExtendedInformation = props.zip64ExtendedInformation;
    }
    /**
     * Return the file modification time, taking extra fields into account.
     */
    fileModificationResolved() {
        // TODO(cemmer): 0x000d UNIX timestamp
        // TODO(cemmer): 0x7855 unix extra field new?
        return (TimestampUtil.parseExtendedTimestamp(this.extraFields.get(0x54_55))?.modified ??
            TimestampUtil.parseUnixExtraTimestamp(this.extraFields.get(0x58_55))?.modified ??
            TimestampUtil.parseNtfsExtraTimestamp(this.extraFields.get(0x00_0a))?.modified ??
            TimestampUtil.parseDOSTimestamp(this.fileModificationTime, this.fileModificationDate));
    }
    /**
     * Return the numerical CRC32.
     */
    uncompressedCrc32Number() {
        return this.uncompressedCrc32.readUInt32LE();
    }
    /**
     * Return the lowercased and padded CRC32 string
     */
    uncompressedCrc32String() {
        return this.uncompressedCrc32Number().toString(16).toLowerCase().padStart(8, '0');
    }
    /**
     * Return the compressed size, taking zip64 information into account.
     */
    compressedSizeResolved() {
        return (this.zip64ExtendedInformation?.compressedSize ??
            this.compressedSize - (this.isEncrypted() ? 12 : 0));
    }
    /**
     * Return the uncompressed size, taking zip64 information into account.
     */
    uncompressedSizeResolved() {
        return this.zip64ExtendedInformation?.uncompressedSize ?? this.uncompressedSize;
    }
    /**
     * Return the file name, taking extra fields into account.
     */
    fileNameResolved() {
        return (
        // Info-ZIP Unicode Path Extra Field
        this.extraFields.get(0x70_75)?.subarray(5).toString('utf8') ??
            (this.generalPurposeBitFlag & 0x8_00
                ? this.fileName.toString('utf8')
                : CP437Decoder.decode(this.fileName)));
    }
    /**
     * Return if this file is encrypted.
     */
    isEncrypted() {
        return (this.generalPurposeBitFlag & 0x01) !== 0;
    }
    /**
     * Return if this file has a data descriptor.
     */
    hasDataDescriptor() {
        return (this.generalPurposeBitFlag & 0x08) !== 0;
    }
    /**
     * Return if this file is a directory.
     */
    isDirectory() {
        return this.fileNameResolved().endsWith('/');
    }
}