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import { ZIP_CENTRAL_DIRECTORY } from "./const.ts";import { File } from "../types.ts";
export interface CentralDirectoryFileHeader {  name: string;  compression: number;  localOffset: number;  compressedSize: number;  uncompressedSize: number;}export async function getCDirView(  file: File,  offset: number,): Promise<DataView> {  const temp = new Uint8Array(ZIP_CENTRAL_DIRECTORY.MIN_LENGTH);  const tempView = new DataView(temp.buffer);  await file.seek(offset, Deno.SeekMode.Start);  await file.read(temp);  const size = getCDirSize(tempView);  const cdir = new Uint8Array(size);  await file.seek(offset, Deno.SeekMode.Start);  await file.read(cdir);  return new DataView(cdir.buffer);}export function getCDirSize(view: DataView): number {  return ZIP_CENTRAL_DIRECTORY.MIN_LENGTH + view.getUint16(28, true) +    view.getUint16(30, true) + view.getUint16(32, true);}export function getCDirectoryObject(  view: DataView,): CentralDirectoryFileHeader {  const compression = view.getUint8(    ZIP_CENTRAL_DIRECTORY.COMPRESSION_OFFSET,  );  const nameLength = view.getUint16(    ZIP_CENTRAL_DIRECTORY.NAME_LENGTH_OFFSET,    true,  );  const name = new TextDecoder().decode(    view.buffer.slice(      ZIP_CENTRAL_DIRECTORY.FILE_NAME_OFFSET,      ZIP_CENTRAL_DIRECTORY.FILE_NAME_OFFSET + nameLength,    ),  );  const localOffset = view.getUint32(    ZIP_CENTRAL_DIRECTORY.LOCAL_FILE_HEADER_OFFSET,    true,  );  const compressedSize = view.getUint32(    ZIP_CENTRAL_DIRECTORY.COMPRESSED_SIZE_OFFSET,    true,  );  const uncompressedSize = view.getUint32(    ZIP_CENTRAL_DIRECTORY.UNCOMPRESSED_SIZE_OFFSET,    true,  );  const cdir = {    compression,    name,    localOffset,    compressedSize,    uncompressedSize,  };  return cdir;}