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import { ZIP_CENTRAL_RECORD } from "./const.ts";import { File, FsOffset } from "../types.ts";
export async function getCRecordView(  file: File,): Promise<DataView | null> {  const crecordOffset = await getCRecordOffset(file);  if (!crecordOffset) return null;  const crecord = new Uint8Array(22);  const crview = new DataView(crecord.buffer);  await file.seek(crecordOffset.offset, crecordOffset.whence);  await file.read(crecord);  return crview;  async function getCRecordOffset(    file: File,  ): Promise<FsOffset | null> {    const u8s = new Uint8Array(4);    const view = new DataView(u8s.buffer);    const { size } = await file.stat();    let i = ZIP_CENTRAL_RECORD.MIN_LENGTH;    if (size >= ZIP_CENTRAL_RECORD.MIN_LENGTH) {      do {        await file.seek(-i, Deno.SeekMode.End);        await file.read(u8s);        if (view.getUint32(0, true) === ZIP_CENTRAL_RECORD.SIGNATURE) {          return { offset: -i, whence: Deno.SeekMode.End };        }      } while (i++);    }    return null;  }}export function getCRecordObject(view: DataView) {  const sig = view.getUint32(0, true);  const cdirCount = view.getUint16(8, true);  const cdirSize = view.getUint32(12, true);  const cdirOffset = view.getUint32(16, true);  return {    sig: sig === 0x06054b50,    cdirCount,    cdirSize,    cdirOffset,  };}