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// from https://github.com/nodeca/pakoimport * as zlibDeflate from "./zlib/deflate.ts";import { concatUint8Array } from "../utils/uint8.ts";import { CODE, message as msg } from "./zlib/messages.ts";import ZStream from "./zlib/zstream.ts";import STATUS from "./zlib/status.ts";
export interface DeflateOptions {  level?: number;  method?: number;  chunkSize?: number;  windowBits?: number;  memLevel?: number;  strategy?: number;  to?: string;  raw?: boolean;  gzip?: boolean;  dictionary?: Uint8Array;  header?: zlibDeflate.Header;}
export class Deflate {  err: STATUS = 0; // error code, if happens (0 = Z_OK)  msg = ""; // error message  ended = false; // used to avoid multiple onEnd() calls  strm: ZStream;  _dict_set = false;  options: any;
  constructor(options: DeflateOptions = {}) {    this.options = Object.assign({      level: STATUS.Z_DEFAULT_COMPRESSION,      method: STATUS.Z_DEFLATED,      chunkSize: 16384,      windowBits: 15,      memLevel: 8,      strategy: STATUS.Z_DEFAULT_STRATEGY,      to: "",    }, options);
    const opt = this.options;
    if (opt.raw && (opt.windowBits > 0)) {      opt.windowBits = -opt.windowBits;    } else if (opt.gzip && (opt.windowBits > 0) && (opt.windowBits < 16)) {      opt.windowBits += 16;    }
    this.strm = new ZStream();    this.strm.avail_out = 0;
    let status = zlibDeflate.deflateInit2(      this.strm,      opt.level,      opt.method,      opt.windowBits,      opt.memLevel,      opt.strategy,    );
    if (status !== STATUS.Z_OK) {      throw new Error(msg[status]);    }
    if (opt.header) {      zlibDeflate.deflateSetHeader(this.strm, opt.header);    }
    if (opt.dictionary) {      status = zlibDeflate.deflateSetDictionary(this.strm, opt.dictionary);
      if (status !== STATUS.Z_OK) {        throw new Error(msg[status]);      }
      this._dict_set = true;    }  }
  push(data: Uint8Array, mode: boolean | number): Uint8Array {    const strm = this.strm;    const chunkSize = this.options.chunkSize;    const chunks: Uint8Array[] = [];    let status;
    if (this.ended) {      throw new Error("can not call after ended");    }
    const _mode = mode === ~~mode      ? mode      : (mode === true ? STATUS.Z_FINISH : STATUS.Z_NO_FLUSH);
    strm.input = data;    strm.next_in = 0;    strm.avail_in = strm.input.length;
    do {      if (strm.avail_out === 0) {        strm.output = new Uint8Array(chunkSize);        strm.next_out = 0;        strm.avail_out = chunkSize;      }      status = zlibDeflate.deflate(strm, _mode); /* no bad return value */
      if (status !== STATUS.Z_STREAM_END && status !== STATUS.Z_OK) {        this.ended = true;        throw new Error(this.strm.msg);      }      if (        strm.avail_out === 0 ||        (strm.avail_in === 0 &&          (_mode === STATUS.Z_FINISH || _mode === STATUS.Z_SYNC_FLUSH))      ) {        chunks.push(strm.output!.subarray(0, strm.next_out));      }    } while (      (strm.avail_in > 0 || strm.avail_out === 0) &&      status !== STATUS.Z_STREAM_END    );
    // Finalize on the last chunk.    if (_mode === STATUS.Z_FINISH) {      status = zlibDeflate.deflateEnd(this.strm);      this.ended = true;      if (status !== STATUS.Z_OK) throw new Error(this.strm.msg);    }
    // callback interim results if Z_SYNC_FLUSH.    if (_mode === STATUS.Z_SYNC_FLUSH) {      strm.avail_out = 0;    }
    return concatUint8Array(chunks);  }}
export function deflate(input: Uint8Array, options: DeflateOptions = {}) {  const deflator = new Deflate(options);  const result = deflator.push(input, true);  // That will never happens, if you don't cheat with options :)  if (deflator.err) throw deflator.msg || msg[deflator.err as CODE];  return result;}
export function deflateRaw(input: Uint8Array, options: DeflateOptions = {}) {  options.raw = true;  return deflate(input, options);}
export function gzip(input: Uint8Array, options: DeflateOptions = {}) {  options.gzip = true;  return deflate(input, options);}