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resources/lib/pako/pako_deflate.js

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/*! pako 2.1.0 https://github.com/nodeca/pako @license (MIT AND Zlib) */
(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
  typeof define === 'function' && define.amd ? define(['exports'], factory) :
  (global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.pako = {}));
})(this, (function (exports) { 'use strict';

  // (C) 1995-2013 Jean-loup Gailly and Mark Adler
  // (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
  //
  // This software is provided 'as-is', without any express or implied
  // warranty. In no event will the authors be held liable for any damages
  // arising from the use of this software.
  //
  // Permission is granted to anyone to use this software for any purpose,
  // including commercial applications, and to alter it and redistribute it
  // freely, subject to the following restrictions:
  //
  // 1. The origin of this software must not be misrepresented; you must not
  //   claim that you wrote the original software. If you use this software
  //   in a product, an acknowledgment in the product documentation would be
  //   appreciated but is not required.
  // 2. Altered source versions must be plainly marked as such, and must not be
  //   misrepresented as being the original software.
  // 3. This notice may not be removed or altered from any source distribution.

  /* eslint-disable space-unary-ops */

  /* Public constants ==========================================================*/
  /* ===========================================================================*/


  //const Z_FILTERED          = 1;
  //const Z_HUFFMAN_ONLY      = 2;
  //const Z_RLE               = 3;
  const Z_FIXED$1               = 4;
  //const Z_DEFAULT_STRATEGY  = 0;

  /* Possible values of the data_type field (though see inflate()) */
  const Z_BINARY              = 0;
  const Z_TEXT                = 1;
  //const Z_ASCII             = 1; // = Z_TEXT
  const Z_UNKNOWN$1             = 2;

  /*============================================================================*/


  function zero$1(buf) { let len = buf.length; while (--len >= 0) { buf[len] = 0; } }

  // From zutil.h

  const STORED_BLOCK = 0;
  const STATIC_TREES = 1;
  const DYN_TREES    = 2;
  /* The three kinds of block type */

  const MIN_MATCH$1    = 3;
  const MAX_MATCH$1    = 258;
  /* The minimum and maximum match lengths */

  // From deflate.h
  /* ===========================================================================
   * Internal compression state.
   */

  const LENGTH_CODES$1  = 29;
  /* number of length codes, not counting the special END_BLOCK code */

  const LITERALS$1      = 256;
  /* number of literal bytes 0..255 */

  const L_CODES$1       = LITERALS$1 + 1 + LENGTH_CODES$1;
  /* number of Literal or Length codes, including the END_BLOCK code */

  const D_CODES$1       = 30;
  /* number of distance codes */

  const BL_CODES$1      = 19;
  /* number of codes used to transfer the bit lengths */

  const HEAP_SIZE$1     = 2 * L_CODES$1 + 1;
  /* maximum heap size */

  const MAX_BITS$1      = 15;
  /* All codes must not exceed MAX_BITS bits */

  const Buf_size      = 16;
  /* size of bit buffer in bi_buf */


  /* ===========================================================================
   * Constants
   */

  const MAX_BL_BITS = 7;
  /* Bit length codes must not exceed MAX_BL_BITS bits */

  const END_BLOCK   = 256;
  /* end of block literal code */

  const REP_3_6     = 16;
  /* repeat previous bit length 3-6 times (2 bits of repeat count) */

  const REPZ_3_10   = 17;
  /* repeat a zero length 3-10 times  (3 bits of repeat count) */

  const REPZ_11_138 = 18;
  /* repeat a zero length 11-138 times  (7 bits of repeat count) */

  /* eslint-disable comma-spacing,array-bracket-spacing */
  const extra_lbits =   /* extra bits for each length code */
    new Uint8Array([0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0]);

  const extra_dbits =   /* extra bits for each distance code */
    new Uint8Array([0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13]);

  const extra_blbits =  /* extra bits for each bit length code */
    new Uint8Array([0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7]);

  const bl_order =
    new Uint8Array([16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15]);
  /* eslint-enable comma-spacing,array-bracket-spacing */

  /* The lengths of the bit length codes are sent in order of decreasing
   * probability, to avoid transmitting the lengths for unused bit length codes.
   */

  /* ===========================================================================
   * Local data. These are initialized only once.
   */

  // We pre-fill arrays with 0 to avoid uninitialized gaps

  const DIST_CODE_LEN = 512; /* see definition of array dist_code below */

  // !!!! Use flat array instead of structure, Freq = i*2, Len = i*2+1
  const static_ltree  = new Array((L_CODES$1 + 2) * 2);
  zero$1(static_ltree);
  /* The static literal tree. Since the bit lengths are imposed, there is no
   * need for the L_CODES extra codes used during heap construction. However
   * The codes 286 and 287 are needed to build a canonical tree (see _tr_init
   * below).
   */

  const static_dtree  = new Array(D_CODES$1 * 2);
  zero$1(static_dtree);
  /* The static distance tree. (Actually a trivial tree since all codes use
   * 5 bits.)
   */

  const _dist_code    = new Array(DIST_CODE_LEN);
  zero$1(_dist_code);
  /* Distance codes. The first 256 values correspond to the distances
   * 3 .. 258, the last 256 values correspond to the top 8 bits of
   * the 15 bit distances.
   */

  const _length_code  = new Array(MAX_MATCH$1 - MIN_MATCH$1 + 1);
  zero$1(_length_code);
  /* length code for each normalized match length (0 == MIN_MATCH) */

  const base_length   = new Array(LENGTH_CODES$1);
  zero$1(base_length);
  /* First normalized length for each code (0 = MIN_MATCH) */

  const base_dist     = new Array(D_CODES$1);
  zero$1(base_dist);
  /* First normalized distance for each code (0 = distance of 1) */


  function StaticTreeDesc(static_tree, extra_bits, extra_base, elems, max_length) {

    this.static_tree  = static_tree;  /* static tree or NULL */
    this.extra_bits   = extra_bits;   /* extra bits for each code or NULL */
    this.extra_base   = extra_base;   /* base index for extra_bits */
    this.elems        = elems;        /* max number of elements in the tree */
    this.max_length   = max_length;   /* max bit length for the codes */

    // show if `static_tree` has data or dummy - needed for monomorphic objects
    this.has_stree    = static_tree && static_tree.length;
  }


  let static_l_desc;
  let static_d_desc;
  let static_bl_desc;


  function TreeDesc(dyn_tree, stat_desc) {
    this.dyn_tree = dyn_tree;     /* the dynamic tree */
    this.max_code = 0;            /* largest code with non zero frequency */
    this.stat_desc = stat_desc;   /* the corresponding static tree */
  }



  const d_code = (dist) => {

    return dist < 256 ? _dist_code[dist] : _dist_code[256 + (dist >>> 7)];
  };


  /* ===========================================================================
   * Output a short LSB first on the stream.
   * IN assertion: there is enough room in pendingBuf.
   */
  const put_short = (s, w) => {
  //    put_byte(s, (uch)((w) & 0xff));
  //    put_byte(s, (uch)((ush)(w) >> 8));
    s.pending_buf[s.pending++] = (w) & 0xff;
    s.pending_buf[s.pending++] = (w >>> 8) & 0xff;
  };


  /* ===========================================================================
   * Send a value on a given number of bits.
   * IN assertion: length <= 16 and value fits in length bits.
   */
  const send_bits = (s, value, length) => {

    if (s.bi_valid > (Buf_size - length)) {
      s.bi_buf |= (value << s.bi_valid) & 0xffff;
      put_short(s, s.bi_buf);
      s.bi_buf = value >> (Buf_size - s.bi_valid);
      s.bi_valid += length - Buf_size;
    } else {
      s.bi_buf |= (value << s.bi_valid) & 0xffff;
      s.bi_valid += length;
    }
  };


  const send_code = (s, c, tree) => {

    send_bits(s, tree[c * 2]/*.Code*/, tree[c * 2 + 1]/*.Len*/);
  };


  /* ===========================================================================
   * Reverse the first len bits of a code, using straightforward code (a faster
   * method would use a table)
   * IN assertion: 1 <= len <= 15
   */
  const bi_reverse = (code, len) => {

    let res = 0;
    do {
      res |= code & 1;
      code >>>= 1;
      res <<= 1;
    } while (--len > 0);
    return res >>> 1;
  };


  /* ===========================================================================
   * Flush the bit buffer, keeping at most 7 bits in it.
   */
  const bi_flush = (s) => {

    if (s.bi_valid === 16) {
      put_short(s, s.bi_buf);
      s.bi_buf = 0;
      s.bi_valid = 0;

    } else if (s.bi_valid >= 8) {
      s.pending_buf[s.pending++] = s.bi_buf & 0xff;
      s.bi_buf >>= 8;
      s.bi_valid -= 8;
    }
  };


  /* ===========================================================================
   * Compute the optimal bit lengths for a tree and update the total bit length
   * for the current block.
   * IN assertion: the fields freq and dad are set, heap[heap_max] and
   *    above are the tree nodes sorted by increasing frequency.
   * OUT assertions: the field len is set to the optimal bit length, the
   *     array bl_count contains the frequencies for each bit length.
   *     The length opt_len is updated; static_len is also updated if stree is
   *     not null.
   */
  const gen_bitlen = (s, desc) => {
  //    deflate_state *s;
  //    tree_desc *desc;    /* the tree descriptor */

    const tree            = desc.dyn_tree;
    const max_code        = desc.max_code;
    const stree           = desc.stat_desc.static_tree;
    const has_stree       = desc.stat_desc.has_stree;
    const extra           = desc.stat_desc.extra_bits;
    const base            = desc.stat_desc.extra_base;
    const max_length      = desc.stat_desc.max_length;
    let h;              /* heap index */
    let n, m;           /* iterate over the tree elements */
    let bits;           /* bit length */
    let xbits;          /* extra bits */
    let f;              /* frequency */
    let overflow = 0;   /* number of elements with bit length too large */

    for (bits = 0; bits <= MAX_BITS$1; bits++) {
      s.bl_count[bits] = 0;
    }

    /* In a first pass, compute the optimal bit lengths (which may
     * overflow in the case of the bit length tree).
     */
    tree[s.heap[s.heap_max] * 2 + 1]/*.Len*/ = 0; /* root of the heap */

    for (h = s.heap_max + 1; h < HEAP_SIZE$1; h++) {
      n = s.heap[h];
      bits = tree[tree[n * 2 + 1]/*.Dad*/ * 2 + 1]/*.Len*/ + 1;
      if (bits > max_length) {
        bits = max_length;
        overflow++;
      }
      tree[n * 2 + 1]/*.Len*/ = bits;
      /* We overwrite tree[n].Dad which is no longer needed */

      if (n > max_code) { continue; } /* not a leaf node */

      s.bl_count[bits]++;
      xbits = 0;
      if (n >= base) {
        xbits = extra[n - base];
      }
      f = tree[n * 2]/*.Freq*/;
      s.opt_len += f * (bits + xbits);
      if (has_stree) {
        s.static_len += f * (stree[n * 2 + 1]/*.Len*/ + xbits);
      }
    }
    if (overflow === 0) { return; }

    // Tracev((stderr,"\nbit length overflow\n"));
    /* This happens for example on obj2 and pic of the Calgary corpus */

    /* Find the first bit length which could increase: */
    do {
      bits = max_length - 1;
      while (s.bl_count[bits] === 0) { bits--; }
      s.bl_count[bits]--;      /* move one leaf down the tree */
      s.bl_count[bits + 1] += 2; /* move one overflow item as its brother */
      s.bl_count[max_length]--;
      /* The brother of the overflow item also moves one step up,
       * but this does not affect bl_count[max_length]
       */
      overflow -= 2;
    } while (overflow > 0);

    /* Now recompute all bit lengths, scanning in increasing frequency.
     * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
     * lengths instead of fixing only the wrong ones. This idea is taken
     * from 'ar' written by Haruhiko Okumura.)
     */
    for (bits = max_length; bits !== 0; bits--) {
      n = s.bl_count[bits];
      while (n !== 0) {
        m = s.heap[--h];
        if (m > max_code) { continue; }
        if (tree[m * 2 + 1]/*.Len*/ !== bits) {
          // Tracev((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
          s.opt_len += (bits - tree[m * 2 + 1]/*.Len*/) * tree[m * 2]/*.Freq*/;
          tree[m * 2 + 1]/*.Len*/ = bits;
        }
        n--;
      }
    }
  };


  /* ===========================================================================
   * Generate the codes for a given tree and bit counts (which need not be
   * optimal).
   * IN assertion: the array bl_count contains the bit length statistics for
   * the given tree and the field len is set for all tree elements.
   * OUT assertion: the field code is set for all tree elements of non
   *     zero code length.
   */
  const gen_codes = (tree, max_code, bl_count) => {
  //    ct_data *tree;             /* the tree to decorate */
  //    int max_code;              /* largest code with non zero frequency */
  //    ushf *bl_count;            /* number of codes at each bit length */

    const next_code = new Array(MAX_BITS$1 + 1); /* next code value for each bit length */
    let code = 0;              /* running code value */
    let bits;                  /* bit index */
    let n;                     /* code index */

    /* The distribution counts are first used to generate the code values
     * without bit reversal.
     */
    for (bits = 1; bits <= MAX_BITS$1; bits++) {
      code = (code + bl_count[bits - 1]) << 1;
      next_code[bits] = code;
    }
    /* Check that the bit counts in bl_count are consistent. The last code
     * must be all ones.
     */
    //Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
    //        "inconsistent bit counts");
    //Tracev((stderr,"\ngen_codes: max_code %d ", max_code));

    for (n = 0;  n <= max_code; n++) {
      let len = tree[n * 2 + 1]/*.Len*/;
      if (len === 0) { continue; }
      /* Now reverse the bits */
      tree[n * 2]/*.Code*/ = bi_reverse(next_code[len]++, len);

      //Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
      //     n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
    }
  };


  /* ===========================================================================
   * Initialize the various 'constant' tables.
   */
  const tr_static_init = () => {

    let n;        /* iterates over tree elements */
    let bits;     /* bit counter */
    let length;   /* length value */
    let code;     /* code value */
    let dist;     /* distance index */
    const bl_count = new Array(MAX_BITS$1 + 1);
    /* number of codes at each bit length for an optimal tree */

    // do check in _tr_init()
    //if (static_init_done) return;

    /* For some embedded targets, global variables are not initialized: */
  /*#ifdef NO_INIT_GLOBAL_POINTERS
    static_l_desc.static_tree = static_ltree;
    static_l_desc.extra_bits = extra_lbits;
    static_d_desc.static_tree = static_dtree;
    static_d_desc.extra_bits = extra_dbits;
    static_bl_desc.extra_bits = extra_blbits;
  #endif*/

    /* Initialize the mapping length (0..255) -> length code (0..28) */
    length = 0;
    for (code = 0; code < LENGTH_CODES$1 - 1; code++) {
      base_length[code] = length;
      for (n = 0; n < (1 << extra_lbits[code]); n++) {
        _length_code[length++] = code;
      }
    }
    //Assert (length == 256, "tr_static_init: length != 256");
    /* Note that the length 255 (match length 258) can be represented
     * in two different ways: code 284 + 5 bits or code 285, so we
     * overwrite length_code[255] to use the best encoding:
     */
    _length_code[length - 1] = code;

    /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
    dist = 0;
    for (code = 0; code < 16; code++) {
      base_dist[code] = dist;
      for (n = 0; n < (1 << extra_dbits[code]); n++) {
        _dist_code[dist++] = code;
      }
    }
    //Assert (dist == 256, "tr_static_init: dist != 256");
    dist >>= 7; /* from now on, all distances are divided by 128 */
    for (; code < D_CODES$1; code++) {
      base_dist[code] = dist << 7;
      for (n = 0; n < (1 << (extra_dbits[code] - 7)); n++) {
        _dist_code[256 + dist++] = code;
      }
    }
    //Assert (dist == 256, "tr_static_init: 256+dist != 512");

    /* Construct the codes of the static literal tree */
    for (bits = 0; bits <= MAX_BITS$1; bits++) {
      bl_count[bits] = 0;
    }

    n = 0;
    while (n <= 143) {
      static_ltree[n * 2 + 1]/*.Len*/ = 8;
      n++;
      bl_count[8]++;
    }
    while (n <= 255) {
      static_ltree[n * 2 + 1]/*.Len*/ = 9;
      n++;
      bl_count[9]++;
    }
    while (n <= 279) {
      static_ltree[n * 2 + 1]/*.Len*/ = 7;
      n++;
      bl_count[7]++;
    }
    while (n <= 287) {
      static_ltree[n * 2 + 1]/*.Len*/ = 8;
      n++;
      bl_count[8]++;
    }
    /* Codes 286 and 287 do not exist, but we must include them in the
     * tree construction to get a canonical Huffman tree (longest code
     * all ones)
     */
    gen_codes(static_ltree, L_CODES$1 + 1, bl_count);

    /* The static distance tree is trivial: */
    for (n = 0; n < D_CODES$1; n++) {
      static_dtree[n * 2 + 1]/*.Len*/ = 5;
      static_dtree[n * 2]/*.Code*/ = bi_reverse(n, 5);
    }

    // Now data ready and we can init static trees
    static_l_desc = new StaticTreeDesc(static_ltree, extra_lbits, LITERALS$1 + 1, L_CODES$1, MAX_BITS$1);
    static_d_desc = new StaticTreeDesc(static_dtree, extra_dbits, 0,          D_CODES$1, MAX_BITS$1);
    static_bl_desc = new StaticTreeDesc(new Array(0), extra_blbits, 0,         BL_CODES$1, MAX_BL_BITS);

    //static_init_done = true;
  };


  /* ===========================================================================
   * Initialize a new block.
   */
  const init_block = (s) => {

    let n; /* iterates over tree elements */

    /* Initialize the trees. */
    for (n = 0; n < L_CODES$1;  n++) { s.dyn_ltree[n * 2]/*.Freq*/ = 0; }
    for (n = 0; n < D_CODES$1;  n++) { s.dyn_dtree[n * 2]/*.Freq*/ = 0; }
    for (n = 0; n < BL_CODES$1; n++) { s.bl_tree[n * 2]/*.Freq*/ = 0; }

    s.dyn_ltree[END_BLOCK * 2]/*.Freq*/ = 1;
    s.opt_len = s.static_len = 0;
    s.sym_next = s.matches = 0;
  };


  /* ===========================================================================
   * Flush the bit buffer and align the output on a byte boundary
   */
  const bi_windup = (s) =>
  {
    if (s.bi_valid > 8) {
      put_short(s, s.bi_buf);
    } else if (s.bi_valid > 0) {
      //put_byte(s, (Byte)s->bi_buf);
      s.pending_buf[s.pending++] = s.bi_buf;
    }
    s.bi_buf = 0;
    s.bi_valid = 0;
  };

  /* ===========================================================================
   * Compares to subtrees, using the tree depth as tie breaker when
   * the subtrees have equal frequency. This minimizes the worst case length.
   */
  const smaller = (tree, n, m, depth) => {

    const _n2 = n * 2;
    const _m2 = m * 2;
    return (tree[_n2]/*.Freq*/ < tree[_m2]/*.Freq*/ ||
           (tree[_n2]/*.Freq*/ === tree[_m2]/*.Freq*/ && depth[n] <= depth[m]));
  };

  /* ===========================================================================
   * Restore the heap property by moving down the tree starting at node k,
   * exchanging a node with the smallest of its two sons if necessary, stopping
   * when the heap property is re-established (each father smaller than its
   * two sons).
   */
  const pqdownheap = (s, tree, k) => {
  //    deflate_state *s;
  //    ct_data *tree;  /* the tree to restore */
  //    int k;               /* node to move down */

    const v = s.heap[k];
    let j = k << 1;  /* left son of k */
    while (j <= s.heap_len) {
      /* Set j to the smallest of the two sons: */
      if (j < s.heap_len &&
        smaller(tree, s.heap[j + 1], s.heap[j], s.depth)) {
        j++;
      }
      /* Exit if v is smaller than both sons */
      if (smaller(tree, v, s.heap[j], s.depth)) { break; }

      /* Exchange v with the smallest son */
      s.heap[k] = s.heap[j];
      k = j;

      /* And continue down the tree, setting j to the left son of k */
      j <<= 1;
    }
    s.heap[k] = v;
  };


  // inlined manually
  // const SMALLEST = 1;

  /* ===========================================================================
   * Send the block data compressed using the given Huffman trees
   */
  const compress_block = (s, ltree, dtree) => {
  //    deflate_state *s;
  //    const ct_data *ltree; /* literal tree */
  //    const ct_data *dtree; /* distance tree */

    let dist;           /* distance of matched string */
    let lc;             /* match length or unmatched char (if dist == 0) */
    let sx = 0;         /* running index in sym_buf */
    let code;           /* the code to send */
    let extra;          /* number of extra bits to send */

    if (s.sym_next !== 0) {
      do {
        dist = s.pending_buf[s.sym_buf + sx++] & 0xff;
        dist += (s.pending_buf[s.sym_buf + sx++] & 0xff) << 8;
        lc = s.pending_buf[s.sym_buf + sx++];
        if (dist === 0) {
          send_code(s, lc, ltree); /* send a literal byte */
          //Tracecv(isgraph(lc), (stderr," '%c' ", lc));
        } else {
          /* Here, lc is the match length - MIN_MATCH */
          code = _length_code[lc];
          send_code(s, code + LITERALS$1 + 1, ltree); /* send the length code */
          extra = extra_lbits[code];
          if (extra !== 0) {
            lc -= base_length[code];
            send_bits(s, lc, extra);       /* send the extra length bits */
          }
          dist--; /* dist is now the match distance - 1 */
          code = d_code(dist);
          //Assert (code < D_CODES, "bad d_code");

          send_code(s, code, dtree);       /* send the distance code */
          extra = extra_dbits[code];
          if (extra !== 0) {
            dist -= base_dist[code];
            send_bits(s, dist, extra);   /* send the extra distance bits */
          }
        } /* literal or match pair ? */

        /* Check that the overlay between pending_buf and sym_buf is ok: */
        //Assert(s->pending < s->lit_bufsize + sx, "pendingBuf overflow");

      } while (sx < s.sym_next);
    }

    send_code(s, END_BLOCK, ltree);
  };


  /* ===========================================================================
   * Construct one Huffman tree and assigns the code bit strings and lengths.
   * Update the total bit length for the current block.
   * IN assertion: the field freq is set for all tree elements.
   * OUT assertions: the fields len and code are set to the optimal bit length
   *     and corresponding code. The length opt_len is updated; static_len is
   *     also updated if stree is not null. The field max_code is set.
   */
  const build_tree = (s, desc) => {
  //    deflate_state *s;
  //    tree_desc *desc; /* the tree descriptor */

    const tree     = desc.dyn_tree;
    const stree    = desc.stat_desc.static_tree;
    const has_stree = desc.stat_desc.has_stree;
    const elems    = desc.stat_desc.elems;
    let n, m;          /* iterate over heap elements */
    let max_code = -1; /* largest code with non zero frequency */
    let node;          /* new node being created */

    /* Construct the initial heap, with least frequent element in
     * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
     * heap[0] is not used.
     */
    s.heap_len = 0;
    s.heap_max = HEAP_SIZE$1;

    for (n = 0; n < elems; n++) {
      if (tree[n * 2]/*.Freq*/ !== 0) {
        s.heap[++s.heap_len] = max_code = n;
        s.depth[n] = 0;

      } else {
        tree[n * 2 + 1]/*.Len*/ = 0;
      }
    }

    /* The pkzip format requires that at least one distance code exists,
     * and that at least one bit should be sent even if there is only one
     * possible code. So to avoid special checks later on we force at least
     * two codes of non zero frequency.
     */
    while (s.heap_len < 2) {
      node = s.heap[++s.heap_len] = (max_code < 2 ? ++max_code : 0);
      tree[node * 2]/*.Freq*/ = 1;
      s.depth[node] = 0;
      s.opt_len--;

      if (has_stree) {
        s.static_len -= stree[node * 2 + 1]/*.Len*/;
      }
      /* node is 0 or 1 so it does not have extra bits */
    }
    desc.max_code = max_code;

    /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
     * establish sub-heaps of increasing lengths:
     */
    for (n = (s.heap_len >> 1/*int /2*/); n >= 1; n--) { pqdownheap(s, tree, n); }

    /* Construct the Huffman tree by repeatedly combining the least two
     * frequent nodes.
     */
    node = elems;              /* next internal node of the tree */
    do {
      //pqremove(s, tree, n);  /* n = node of least frequency */
      /*** pqremove ***/
      n = s.heap[1/*SMALLEST*/];
      s.heap[1/*SMALLEST*/] = s.heap[s.heap_len--];
      pqdownheap(s, tree, 1/*SMALLEST*/);
      /***/

      m = s.heap[1/*SMALLEST*/]; /* m = node of next least frequency */

      s.heap[--s.heap_max] = n; /* keep the nodes sorted by frequency */
      s.heap[--s.heap_max] = m;

      /* Create a new node father of n and m */
      tree[node * 2]/*.Freq*/ = tree[n * 2]/*.Freq*/ + tree[m * 2]/*.Freq*/;
      s.depth[node] = (s.depth[n] >= s.depth[m] ? s.depth[n] : s.depth[m]) + 1;
      tree[n * 2 + 1]/*.Dad*/ = tree[m * 2 + 1]/*.Dad*/ = node;

      /* and insert the new node in the heap */
      s.heap[1/*SMALLEST*/] = node++;
      pqdownheap(s, tree, 1/*SMALLEST*/);

    } while (s.heap_len >= 2);

    s.heap[--s.heap_max] = s.heap[1/*SMALLEST*/];

    /* At this point, the fields freq and dad are set. We can now
     * generate the bit lengths.
     */
    gen_bitlen(s, desc);

    /* The field len is now set, we can generate the bit codes */
    gen_codes(tree, max_code, s.bl_count);
  };


  /* ===========================================================================
   * Scan a literal or distance tree to determine the frequencies of the codes
   * in the bit length tree.
   */
  const scan_tree = (s, tree, max_code) => {
  //    deflate_state *s;
  //    ct_data *tree;   /* the tree to be scanned */
  //    int max_code;    /* and its largest code of non zero frequency */

    let n;                     /* iterates over all tree elements */
    let prevlen = -1;          /* last emitted length */
    let curlen;                /* length of current code */

    let nextlen = tree[0 * 2 + 1]/*.Len*/; /* length of next code */

    let count = 0;             /* repeat count of the current code */
    let max_count = 7;         /* max repeat count */
    let min_count = 4;         /* min repeat count */

    if (nextlen === 0) {
      max_count = 138;
      min_count = 3;
    }
    tree[(max_code + 1) * 2 + 1]/*.Len*/ = 0xffff; /* guard */

    for (n = 0; n <= max_code; n++) {
      curlen = nextlen;
      nextlen = tree[(n + 1) * 2 + 1]/*.Len*/;

      if (++count < max_count && curlen === nextlen) {
        continue;

      } else if (count < min_count) {
        s.bl_tree[curlen * 2]/*.Freq*/ += count;

      } else if (curlen !== 0) {

        if (curlen !== prevlen) { s.bl_tree[curlen * 2]/*.Freq*/++; }
        s.bl_tree[REP_3_6 * 2]/*.Freq*/++;

      } else if (count <= 10) {
        s.bl_tree[REPZ_3_10 * 2]/*.Freq*/++;

      } else {
        s.bl_tree[REPZ_11_138 * 2]/*.Freq*/++;
      }

      count = 0;
      prevlen = curlen;

      if (nextlen === 0) {
        max_count = 138;
        min_count = 3;

      } else if (curlen === nextlen) {
        max_count = 6;
        min_count = 3;

      } else {
        max_count = 7;
        min_count = 4;
      }
    }
  };


  /* ===========================================================================
   * Send a literal or distance tree in compressed form, using the codes in
   * bl_tree.
   */
  const send_tree = (s, tree, max_code) => {
  //    deflate_state *s;
  //    ct_data *tree; /* the tree to be scanned */
  //    int max_code;       /* and its largest code of non zero frequency */

    let n;                     /* iterates over all tree elements */
    let prevlen = -1;          /* last emitted length */
    let curlen;                /* length of current code */

    let nextlen = tree[0 * 2 + 1]/*.Len*/; /* length of next code */

    let count = 0;             /* repeat count of the current code */
    let max_count = 7;         /* max repeat count */
    let min_count = 4;         /* min repeat count */

    /* tree[max_code+1].Len = -1; */  /* guard already set */
    if (nextlen === 0) {
      max_count = 138;
      min_count = 3;
    }

    for (n = 0; n <= max_code; n++) {
      curlen = nextlen;
      nextlen = tree[(n + 1) * 2 + 1]/*.Len*/;

      if (++count < max_count && curlen === nextlen) {
        continue;

      } else if (count < min_count) {
        do { send_code(s, curlen, s.bl_tree); } while (--count !== 0);

      } else if (curlen !== 0) {
        if (curlen !== prevlen) {
          send_code(s, curlen, s.bl_tree);
          count--;
        }
        //Assert(count >= 3 && count <= 6, " 3_6?");
        send_code(s, REP_3_6, s.bl_tree);
        send_bits(s, count - 3, 2);

      } else if (count <= 10) {
        send_code(s, REPZ_3_10, s.bl_tree);
        send_bits(s, count - 3, 3);

      } else {
        send_code(s, REPZ_11_138, s.bl_tree);
        send_bits(s, count - 11, 7);
      }

      count = 0;
      prevlen = curlen;
      if (nextlen === 0) {
        max_count = 138;
        min_count = 3;

      } else if (curlen === nextlen) {
        max_count = 6;
        min_count = 3;

      } else {
        max_count = 7;
        min_count = 4;
      }
    }
  };


  /* ===========================================================================
   * Construct the Huffman tree for the bit lengths and return the index in
   * bl_order of the last bit length code to send.
   */
  const build_bl_tree = (s) => {

    let max_blindex;  /* index of last bit length code of non zero freq */

    /* Determine the bit length frequencies for literal and distance trees */
    scan_tree(s, s.dyn_ltree, s.l_desc.max_code);
    scan_tree(s, s.dyn_dtree, s.d_desc.max_code);

    /* Build the bit length tree: */
    build_tree(s, s.bl_desc);
    /* opt_len now includes the length of the tree representations, except
     * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
     */

    /* Determine the number of bit length codes to send. The pkzip format
     * requires that at least 4 bit length codes be sent. (appnote.txt says
     * 3 but the actual value used is 4.)
     */
    for (max_blindex = BL_CODES$1 - 1; max_blindex >= 3; max_blindex--) {
      if (s.bl_tree[bl_order[max_blindex] * 2 + 1]/*.Len*/ !== 0) {
        break;
      }
    }
    /* Update opt_len to include the bit length tree and counts */
    s.opt_len += 3 * (max_blindex + 1) + 5 + 5 + 4;
    //Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
    //        s->opt_len, s->static_len));

    return max_blindex;
  };


  /* ===========================================================================
   * Send the header for a block using dynamic Huffman trees: the counts, the
   * lengths of the bit length codes, the literal tree and the distance tree.
   * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
   */
  const send_all_trees = (s, lcodes, dcodes, blcodes) => {
  //    deflate_state *s;
  //    int lcodes, dcodes, blcodes; /* number of codes for each tree */

    let rank;                    /* index in bl_order */

    //Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
    //Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
    //        "too many codes");
    //Tracev((stderr, "\nbl counts: "));
    send_bits(s, lcodes - 257, 5); /* not +255 as stated in appnote.txt */
    send_bits(s, dcodes - 1,   5);
    send_bits(s, blcodes - 4,  4); /* not -3 as stated in appnote.txt */
    for (rank = 0; rank < blcodes; rank++) {
      //Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
      send_bits(s, s.bl_tree[bl_order[rank] * 2 + 1]/*.Len*/, 3);
    }
    //Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));

    send_tree(s, s.dyn_ltree, lcodes - 1); /* literal tree */
    //Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));

    send_tree(s, s.dyn_dtree, dcodes - 1); /* distance tree */
    //Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
  };


  /* ===========================================================================
   * Check if the data type is TEXT or BINARY, using the following algorithm:
   * - TEXT if the two conditions below are satisfied:
   *    a) There are no non-portable control characters belonging to the
   *       "block list" (0..6, 14..25, 28..31).
   *    b) There is at least one printable character belonging to the
   *       "allow list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255).
   * - BINARY otherwise.
   * - The following partially-portable control characters form a
   *   "gray list" that is ignored in this detection algorithm:
   *   (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}).
   * IN assertion: the fields Freq of dyn_ltree are set.
   */
  const detect_data_type = (s) => {
    /* block_mask is the bit mask of block-listed bytes
     * set bits 0..6, 14..25, and 28..31
     * 0xf3ffc07f = binary 11110011111111111100000001111111
     */
    let block_mask = 0xf3ffc07f;
    let n;

    /* Check for non-textual ("block-listed") bytes. */
    for (n = 0; n <= 31; n++, block_mask >>>= 1) {
      if ((block_mask & 1) && (s.dyn_ltree[n * 2]/*.Freq*/ !== 0)) {
        return Z_BINARY;
      }
    }

    /* Check for textual ("allow-listed") bytes. */
    if (s.dyn_ltree[9 * 2]/*.Freq*/ !== 0 || s.dyn_ltree[10 * 2]/*.Freq*/ !== 0 ||
        s.dyn_ltree[13 * 2]/*.Freq*/ !== 0) {
      return Z_TEXT;
    }
    for (n = 32; n < LITERALS$1; n++) {
      if (s.dyn_ltree[n * 2]/*.Freq*/ !== 0) {
        return Z_TEXT;
      }
    }

    /* There are no "block-listed" or "allow-listed" bytes:
     * this stream either is empty or has tolerated ("gray-listed") bytes only.
     */
    return Z_BINARY;
  };


  let static_init_done = false;

  /* ===========================================================================
   * Initialize the tree data structures for a new zlib stream.
   */
  const _tr_init$1 = (s) =>
  {

    if (!static_init_done) {
      tr_static_init();
      static_init_done = true;
    }

    s.l_desc  = new TreeDesc(s.dyn_ltree, static_l_desc);
    s.d_desc  = new TreeDesc(s.dyn_dtree, static_d_desc);
    s.bl_desc = new TreeDesc(s.bl_tree, static_bl_desc);

    s.bi_buf = 0;
    s.bi_valid = 0;

    /* Initialize the first block of the first file: */
    init_block(s);
  };


  /* ===========================================================================
   * Send a stored block
   */
  const _tr_stored_block$1 = (s, buf, stored_len, last) => {
  //DeflateState *s;
  //charf *buf;       /* input block */
  //ulg stored_len;   /* length of input block */
  //int last;         /* one if this is the last block for a file */

    send_bits(s, (STORED_BLOCK << 1) + (last ? 1 : 0), 3);    /* send block type */
    bi_windup(s);        /* align on byte boundary */
    put_short(s, stored_len);
    put_short(s, ~stored_len);
    if (stored_len) {
      s.pending_buf.set(s.window.subarray(buf, buf + stored_len), s.pending);
    }
    s.pending += stored_len;
  };


  /* ===========================================================================
   * Send one empty static block to give enough lookahead for inflate.
   * This takes 10 bits, of which 7 may remain in the bit buffer.
   */
  const _tr_align$1 = (s) => {
    send_bits(s, STATIC_TREES << 1, 3);
    send_code(s, END_BLOCK, static_ltree);
    bi_flush(s);
  };


  /* ===========================================================================
   * Determine the best encoding for the current block: dynamic trees, static
   * trees or store, and write out the encoded block.
   */
  const _tr_flush_block$1 = (s, buf, stored_len, last) => {
  //DeflateState *s;
  //charf *buf;       /* input block, or NULL if too old */
  //ulg stored_len;   /* length of input block */
  //int last;         /* one if this is the last block for a file */

    let opt_lenb, static_lenb;  /* opt_len and static_len in bytes */
    let max_blindex = 0;        /* index of last bit length code of non zero freq */

    /* Build the Huffman trees unless a stored block is forced */
    if (s.level > 0) {

      /* Check if the file is binary or text */
      if (s.strm.data_type === Z_UNKNOWN$1) {
        s.strm.data_type = detect_data_type(s);
      }

      /* Construct the literal and distance trees */
      build_tree(s, s.l_desc);
      // Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
      //        s->static_len));

      build_tree(s, s.d_desc);
      // Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
      //        s->static_len));
      /* At this point, opt_len and static_len are the total bit lengths of
       * the compressed block data, excluding the tree representations.
       */

      /* Build the bit length tree for the above two trees, and get the index
       * in bl_order of the last bit length code to send.
       */
      max_blindex = build_bl_tree(s);

      /* Determine the best encoding. Compute the block lengths in bytes. */
      opt_lenb = (s.opt_len + 3 + 7) >>> 3;
      static_lenb = (s.static_len + 3 + 7) >>> 3;

      // Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
      //        opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
      //        s->sym_next / 3));

      if (static_lenb <= opt_lenb) { opt_lenb = static_lenb; }

    } else {
      // Assert(buf != (char*)0, "lost buf");
      opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
    }

    if ((stored_len + 4 <= opt_lenb) && (buf !== -1)) {
      /* 4: two words for the lengths */

      /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
       * Otherwise we can't have processed more than WSIZE input bytes since
       * the last block flush, because compression would have been
       * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
       * transform a block into a stored block.
       */
      _tr_stored_block$1(s, buf, stored_len, last);

    } else if (s.strategy === Z_FIXED$1 || static_lenb === opt_lenb) {

      send_bits(s, (STATIC_TREES << 1) + (last ? 1 : 0), 3);
      compress_block(s, static_ltree, static_dtree);

    } else {
      send_bits(s, (DYN_TREES << 1) + (last ? 1 : 0), 3);
      send_all_trees(s, s.l_desc.max_code + 1, s.d_desc.max_code + 1, max_blindex + 1);
      compress_block(s, s.dyn_ltree, s.dyn_dtree);
    }
    // Assert (s->compressed_len == s->bits_sent, "bad compressed size");
    /* The above check is made mod 2^32, for files larger than 512 MB
     * and uLong implemented on 32 bits.
     */
    init_block(s);

    if (last) {
      bi_windup(s);
    }
    // Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
    //       s->compressed_len-7*last));
  };

  /* ===========================================================================
   * Save the match info and tally the frequency counts. Return true if
   * the current block must be flushed.
   */
  const _tr_tally$1 = (s, dist, lc) => {
  //    deflate_state *s;
  //    unsigned dist;  /* distance of matched string */
  //    unsigned lc;    /* match length-MIN_MATCH or unmatched char (if dist==0) */

    s.pending_buf[s.sym_buf + s.sym_next++] = dist;
    s.pending_buf[s.sym_buf + s.sym_next++] = dist >> 8;
    s.pending_buf[s.sym_buf + s.sym_next++] = lc;
    if (dist === 0) {
      /* lc is the unmatched char */
      s.dyn_ltree[lc * 2]/*.Freq*/++;
    } else {
      s.matches++;
      /* Here, lc is the match length - MIN_MATCH */
      dist--;             /* dist = match distance - 1 */
      //Assert((ush)dist < (ush)MAX_DIST(s) &&
      //       (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
      //       (ush)d_code(dist) < (ush)D_CODES,  "_tr_tally: bad match");

      s.dyn_ltree[(_length_code[lc] + LITERALS$1 + 1) * 2]/*.Freq*/++;
      s.dyn_dtree[d_code(dist) * 2]/*.Freq*/++;
    }

    return (s.sym_next === s.sym_end);
  };

  var _tr_init_1  = _tr_init$1;
  var _tr_stored_block_1 = _tr_stored_block$1;
  var _tr_flush_block_1  = _tr_flush_block$1;
  var _tr_tally_1 = _tr_tally$1;
  var _tr_align_1 = _tr_align$1;

  var trees = {
      _tr_init: _tr_init_1,
      _tr_stored_block: _tr_stored_block_1,
      _tr_flush_block: _tr_flush_block_1,
      _tr_tally: _tr_tally_1,
      _tr_align: _tr_align_1
  };

  // Note: adler32 takes 12% for level 0 and 2% for level 6.
  // It isn't worth it to make additional optimizations as in original.
  // Small size is preferable.

  // (C) 1995-2013 Jean-loup Gailly and Mark Adler
  // (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
  //
  // This software is provided 'as-is', without any express or implied
  // warranty. In no event will the authors be held liable for any damages
  // arising from the use of this software.
  //
  // Permission is granted to anyone to use this software for any purpose,
  // including commercial applications, and to alter it and redistribute it
  // freely, subject to the following restrictions:
  //
  // 1. The origin of this software must not be misrepresented; you must not
  //   claim that you wrote the original software. If you use this software
  //   in a product, an acknowledgment in the product documentation would be
  //   appreciated but is not required.
  // 2. Altered source versions must be plainly marked as such, and must not be
  //   misrepresented as being the original software.
  // 3. This notice may not be removed or altered from any source distribution.

  const adler32 = (adler, buf, len, pos) => {
    let s1 = (adler & 0xffff) |0,
        s2 = ((adler >>> 16) & 0xffff) |0,
        n = 0;

    while (len !== 0) {
      // Set limit ~ twice less than 5552, to keep
      // s2 in 31-bits, because we force signed ints.
      // in other case %= will fail.
      n = len > 2000 ? 2000 : len;
      len -= n;

      do {
        s1 = (s1 + buf[pos++]) |0;
        s2 = (s2 + s1) |0;
      } while (--n);

      s1 %= 65521;
      s2 %= 65521;
    }

    return (s1 | (s2 << 16)) |0;
  };


  var adler32_1 = adler32;

  // Note: we can't get significant speed boost here.
  // So write code to minimize size - no pregenerated tables
  // and array tools dependencies.

  // (C) 1995-2013 Jean-loup Gailly and Mark Adler
  // (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
  //
  // This software is provided 'as-is', without any express or implied
  // warranty. In no event will the authors be held liable for any damages
  // arising from the use of this software.
  //
  // Permission is granted to anyone to use this software for any purpose,
  // including commercial applications, and to alter it and redistribute it
  // freely, subject to the following restrictions:
  //
  // 1. The origin of this software must not be misrepresented; you must not
  //   claim that you wrote the original software. If you use this software
  //   in a product, an acknowledgment in the product documentation would be
  //   appreciated but is not required.
  // 2. Altered source versions must be plainly marked as such, and must not be
  //   misrepresented as being the original software.
  // 3. This notice may not be removed or altered from any source distribution.

  // Use ordinary array, since untyped makes no boost here
  const makeTable = () => {
    let c, table = [];

    for (var n = 0; n < 256; n++) {
      c = n;
      for (var k = 0; k < 8; k++) {
        c = ((c & 1) ? (0xEDB88320 ^ (c >>> 1)) : (c >>> 1));
      }
      table[n] = c;
    }

    return table;
  };

  // Create table on load. Just 255 signed longs. Not a problem.
  const crcTable = new Uint32Array(makeTable());


  const crc32 = (crc, buf, len, pos) => {
    const t = crcTable;
    const end = pos + len;

    crc ^= -1;

    for (let i = pos; i < end; i++) {
      crc = (crc >>> 8) ^ t[(crc ^ buf[i]) & 0xFF];
    }

    return (crc ^ (-1)); // >>> 0;
  };


  var crc32_1 = crc32;

  // (C) 1995-2013 Jean-loup Gailly and Mark Adler
  // (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
  //
  // This software is provided 'as-is', without any express or implied
  // warranty. In no event will the authors be held liable for any damages
  // arising from the use of this software.
  //
  // Permission is granted to anyone to use this software for any purpose,
  // including commercial applications, and to alter it and redistribute it
  // freely, subject to the following restrictions:
  //
  // 1. The origin of this software must not be misrepresented; you must not
  //   claim that you wrote the original software. If you use this software
  //   in a product, an acknowledgment in the product documentation would be
  //   appreciated but is not required.
  // 2. Altered source versions must be plainly marked as such, and must not be
  //   misrepresented as being the original software.
  // 3. This notice may not be removed or altered from any source distribution.

  var messages = {
    2:      'need dictionary',     /* Z_NEED_DICT       2  */
    1:      'stream end',          /* Z_STREAM_END      1  */
    0:      '',                    /* Z_OK              0  */
    '-1':   'file error',          /* Z_ERRNO         (-1) */
    '-2':   'stream error',        /* Z_STREAM_ERROR  (-2) */
    '-3':   'data error',          /* Z_DATA_ERROR    (-3) */
    '-4':   'insufficient memory', /* Z_MEM_ERROR     (-4) */
    '-5':   'buffer error',        /* Z_BUF_ERROR     (-5) */
    '-6':   'incompatible version' /* Z_VERSION_ERROR (-6) */
  };

  // (C) 1995-2013 Jean-loup Gailly and Mark Adler
  // (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
  //
  // This software is provided 'as-is', without any express or implied
  // warranty. In no event will the authors be held liable for any damages
  // arising from the use of this software.
  //
  // Permission is granted to anyone to use this software for any purpose,
  // including commercial applications, and to alter it and redistribute it
  // freely, subject to the following restrictions:
  //
  // 1. The origin of this software must not be misrepresented; you must not
  //   claim that you wrote the original software. If you use this software
  //   in a product, an acknowledgment in the product documentation would be
  //   appreciated but is not required.
  // 2. Altered source versions must be plainly marked as such, and must not be
  //   misrepresented as being the original software.
  // 3. This notice may not be removed or altered from any source distribution.

  var constants$1 = {

    /* Allowed flush values; see deflate() and inflate() below for details */
    Z_NO_FLUSH:         0,
    Z_PARTIAL_FLUSH:    1,
    Z_SYNC_FLUSH:       2,
    Z_FULL_FLUSH:       3,
    Z_FINISH:           4,
    Z_BLOCK:            5,
    Z_TREES:            6,

    /* Return codes for the compression/decompression functions. Negative values
    * are errors, positive values are used for special but normal events.
    */
    Z_OK:               0,
    Z_STREAM_END:       1,
    Z_NEED_DICT:        2,
    Z_ERRNO:           -1,
    Z_STREAM_ERROR:    -2,
    Z_DATA_ERROR:      -3,
    Z_MEM_ERROR:       -4,
    Z_BUF_ERROR:       -5,
    //Z_VERSION_ERROR: -6,

    /* compression levels */
    Z_NO_COMPRESSION:         0,
    Z_BEST_SPEED:             1,
    Z_BEST_COMPRESSION:       9,
    Z_DEFAULT_COMPRESSION:   -1,


    Z_FILTERED:               1,
    Z_HUFFMAN_ONLY:           2,
    Z_RLE:                    3,
    Z_FIXED:                  4,
    Z_DEFAULT_STRATEGY:       0,

    /* Possible values of the data_type field (though see inflate()) */
    Z_BINARY:                 0,
    Z_TEXT:                   1,
    //Z_ASCII:                1, // = Z_TEXT (deprecated)
    Z_UNKNOWN:                2,

    /* The deflate compression method */
    Z_DEFLATED:               8
    //Z_NULL:                 null // Use -1 or null inline, depending on var type
  };

  // (C) 1995-2013 Jean-loup Gailly and Mark Adler
  // (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
  //
  // This software is provided 'as-is', without any express or implied
  // warranty. In no event will the authors be held liable for any damages
  // arising from the use of this software.
  //
  // Permission is granted to anyone to use this software for any purpose,
  // including commercial applications, and to alter it and redistribute it
  // freely, subject to the following restrictions:
  //
  // 1. The origin of this software must not be misrepresented; you must not
  //   claim that you wrote the original software. If you use this software
  //   in a product, an acknowledgment in the product documentation would be
  //   appreciated but is not required.
  // 2. Altered source versions must be plainly marked as such, and must not be
  //   misrepresented as being the original software.
  // 3. This notice may not be removed or altered from any source distribution.

  const { _tr_init, _tr_stored_block, _tr_flush_block, _tr_tally, _tr_align } = trees;




  /* Public constants ==========================================================*/
  /* ===========================================================================*/

  const {
    Z_NO_FLUSH: Z_NO_FLUSH$1, Z_PARTIAL_FLUSH, Z_FULL_FLUSH: Z_FULL_FLUSH$1, Z_FINISH: Z_FINISH$1, Z_BLOCK,
    Z_OK: Z_OK$1, Z_STREAM_END: Z_STREAM_END$1, Z_STREAM_ERROR, Z_DATA_ERROR, Z_BUF_ERROR,
    Z_DEFAULT_COMPRESSION: Z_DEFAULT_COMPRESSION$1,
    Z_FILTERED, Z_HUFFMAN_ONLY, Z_RLE, Z_FIXED, Z_DEFAULT_STRATEGY: Z_DEFAULT_STRATEGY$1,
    Z_UNKNOWN,
    Z_DEFLATED: Z_DEFLATED$1
  } = constants$1;

  /*============================================================================*/


  const MAX_MEM_LEVEL = 9;
  /* Maximum value for memLevel in deflateInit2 */
  const MAX_WBITS = 15;
  /* 32K LZ77 window */
  const DEF_MEM_LEVEL = 8;


  const LENGTH_CODES  = 29;
  /* number of length codes, not counting the special END_BLOCK code */
  const LITERALS      = 256;
  /* number of literal bytes 0..255 */
  const L_CODES       = LITERALS + 1 + LENGTH_CODES;
  /* number of Literal or Length codes, including the END_BLOCK code */
  const D_CODES       = 30;
  /* number of distance codes */
  const BL_CODES      = 19;
  /* number of codes used to transfer the bit lengths */
  const HEAP_SIZE     = 2 * L_CODES + 1;
  /* maximum heap size */
  const MAX_BITS  = 15;
  /* All codes must not exceed MAX_BITS bits */

  const MIN_MATCH = 3;
  const MAX_MATCH = 258;
  const MIN_LOOKAHEAD = (MAX_MATCH + MIN_MATCH + 1);

  const PRESET_DICT = 0x20;

  const INIT_STATE    =  42;    /* zlib header -> BUSY_STATE */
  //#ifdef GZIP
  const GZIP_STATE    =  57;    /* gzip header -> BUSY_STATE | EXTRA_STATE */
  //#endif
  const EXTRA_STATE   =  69;    /* gzip extra block -> NAME_STATE */
  const NAME_STATE    =  73;    /* gzip file name -> COMMENT_STATE */
  const COMMENT_STATE =  91;    /* gzip comment -> HCRC_STATE */
  const HCRC_STATE    = 103;    /* gzip header CRC -> BUSY_STATE */
  const BUSY_STATE    = 113;    /* deflate -> FINISH_STATE */
  const FINISH_STATE  = 666;    /* stream complete */

  const BS_NEED_MORE      = 1; /* block not completed, need more input or more output */
  const BS_BLOCK_DONE     = 2; /* block flush performed */
  const BS_FINISH_STARTED = 3; /* finish started, need only more output at next deflate */
  const BS_FINISH_DONE    = 4; /* finish done, accept no more input or output */

  const OS_CODE = 0x03; // Unix :) . Don't detect, use this default.

  const err = (strm, errorCode) => {
    strm.msg = messages[errorCode];
    return errorCode;
  };

  const rank = (f) => {
    return ((f) * 2) - ((f) > 4 ? 9 : 0);
  };

  const zero = (buf) => {
    let len = buf.length; while (--len >= 0) { buf[len] = 0; }
  };

  /* ===========================================================================
   * Slide the hash table when sliding the window down (could be avoided with 32
   * bit values at the expense of memory usage). We slide even when level == 0 to
   * keep the hash table consistent if we switch back to level > 0 later.
   */
  const slide_hash = (s) => {
    let n, m;
    let p;
    let wsize = s.w_size;

    n = s.hash_size;
    p = n;
    do {
      m = s.head[--p];
      s.head[p] = (m >= wsize ? m - wsize : 0);
    } while (--n);
    n = wsize;
  //#ifndef FASTEST
    p = n;
    do {
      m = s.prev[--p];
      s.prev[p] = (m >= wsize ? m - wsize : 0);
      /* If n is not on any hash chain, prev[n] is garbage but
       * its value will never be used.
       */
    } while (--n);
  //#endif
  };

  /* eslint-disable new-cap */
  let HASH_ZLIB = (s, prev, data) => ((prev << s.hash_shift) ^ data) & s.hash_mask;
  // This hash causes less collisions, https://github.com/nodeca/pako/issues/135
  // But breaks binary compatibility
  //let HASH_FAST = (s, prev, data) => ((prev << 8) + (prev >> 8) + (data << 4)) & s.hash_mask;
  let HASH = HASH_ZLIB;


  /* =========================================================================
   * Flush as much pending output as possible. All deflate() output, except for
   * some deflate_stored() output, goes through this function so some
   * applications may wish to modify it to avoid allocating a large
   * strm->next_out buffer and copying into it. (See also read_buf()).
   */
  const flush_pending = (strm) => {
    const s = strm.state;

    //_tr_flush_bits(s);
    let len = s.pending;
    if (len > strm.avail_out) {
      len = strm.avail_out;
    }
    if (len === 0) { return; }

    strm.output.set(s.pending_buf.subarray(s.pending_out, s.pending_out + len), strm.next_out);
    strm.next_out  += len;
    s.pending_out  += len;
    strm.total_out += len;
    strm.avail_out -= len;
    s.pending      -= len;
    if (s.pending === 0) {
      s.pending_out = 0;
    }
  };


  const flush_block_only = (s, last) => {
    _tr_flush_block(s, (s.block_start >= 0 ? s.block_start : -1), s.strstart - s.block_start, last);
    s.block_start = s.strstart;
    flush_pending(s.strm);
  };


  const put_byte = (s, b) => {
    s.pending_buf[s.pending++] = b;
  };


  /* =========================================================================
   * Put a short in the pending buffer. The 16-bit value is put in MSB order.
   * IN assertion: the stream state is correct and there is enough room in
   * pending_buf.
   */
  const putShortMSB = (s, b) => {

    //  put_byte(s, (Byte)(b >> 8));
  //  put_byte(s, (Byte)(b & 0xff));
    s.pending_buf[s.pending++] = (b >>> 8) & 0xff;
    s.pending_buf[s.pending++] = b & 0xff;
  };


  /* ===========================================================================
   * Read a new buffer from the current input stream, update the adler32
   * and total number of bytes read.  All deflate() input goes through
   * this function so some applications may wish to modify it to avoid
   * allocating a large strm->input buffer and copying from it.
   * (See also flush_pending()).
   */
  const read_buf = (strm, buf, start, size) => {

    let len = strm.avail_in;

    if (len > size) { len = size; }
    if (len === 0) { return 0; }

    strm.avail_in -= len;

    // zmemcpy(buf, strm->next_in, len);
    buf.set(strm.input.subarray(strm.next_in, strm.next_in + len), start);
    if (strm.state.wrap === 1) {
      strm.adler = adler32_1(strm.adler, buf, len, start);
    }

    else if (strm.state.wrap === 2) {
      strm.adler = crc32_1(strm.adler, buf, len, start);
    }

    strm.next_in += len;
    strm.total_in += len;

    return len;
  };


  /* ===========================================================================
   * Set match_start to the longest match starting at the given string and
   * return its length. Matches shorter or equal to prev_length are discarded,
   * in which case the result is equal to prev_length and match_start is
   * garbage.
   * IN assertions: cur_match is the head of the hash chain for the current
   *   string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
   * OUT assertion: the match length is not greater than s->lookahead.
   */
  const longest_match = (s, cur_match) => {

    let chain_length = s.max_chain_length;      /* max hash chain length */
    let scan = s.strstart; /* current string */
    let match;                       /* matched string */
    let len;                           /* length of current match */
    let best_len = s.prev_length;              /* best match length so far */
    let nice_match = s.nice_match;             /* stop if match long enough */
    const limit = (s.strstart > (s.w_size - MIN_LOOKAHEAD)) ?
        s.strstart - (s.w_size - MIN_LOOKAHEAD) : 0/*NIL*/;

    const _win = s.window; // shortcut

    const wmask = s.w_mask;
    const prev  = s.prev;

    /* Stop when cur_match becomes <= limit. To simplify the code,
     * we prevent matches with the string of window index 0.
     */

    const strend = s.strstart + MAX_MATCH;
    let scan_end1  = _win[scan + best_len - 1];
    let scan_end   = _win[scan + best_len];

    /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
     * It is easy to get rid of this optimization if necessary.
     */
    // Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");

    /* Do not waste too much time if we already have a good match: */
    if (s.prev_length >= s.good_match) {
      chain_length >>= 2;
    }
    /* Do not look for matches beyond the end of the input. This is necessary
     * to make deflate deterministic.
     */
    if (nice_match > s.lookahead) { nice_match = s.lookahead; }

    // Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");

    do {
      // Assert(cur_match < s->strstart, "no future");
      match = cur_match;

      /* Skip to next match if the match length cannot increase
       * or if the match length is less than 2.  Note that the checks below
       * for insufficient lookahead only occur occasionally for performance
       * reasons.  Therefore uninitialized memory will be accessed, and
       * conditional jumps will be made that depend on those values.
       * However the length of the match is limited to the lookahead, so
       * the output of deflate is not affected by the uninitialized values.
       */

      if (_win[match + best_len]     !== scan_end  ||
          _win[match + best_len - 1] !== scan_end1 ||
          _win[match]                !== _win[scan] ||
          _win[++match]              !== _win[scan + 1]) {
        continue;
      }

      /* The check at best_len-1 can be removed because it will be made
       * again later. (This heuristic is not always a win.)
       * It is not necessary to compare scan[2] and match[2] since they
       * are always equal when the other bytes match, given that
       * the hash keys are equal and that HASH_BITS >= 8.
       */
      scan += 2;
      match++;
      // Assert(*scan == *match, "match[2]?");

      /* We check for insufficient lookahead only every 8th comparison;
       * the 256th check will be made at strstart+258.
       */
      do {
        /*jshint noempty:false*/
      } while (_win[++scan] === _win[++match] && _win[++scan] === _win[++match] &&
               _win[++scan] === _win[++match] && _win[++scan] === _win[++match] &&
               _win[++scan] === _win[++match] && _win[++scan] === _win[++match] &&
               _win[++scan] === _win[++match] && _win[++scan] === _win[++match] &&
               scan < strend);

      // Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");

      len = MAX_MATCH - (strend - scan);
      scan = strend - MAX_MATCH;

      if (len > best_len) {
        s.match_start = cur_match;
        best_len = len;
        if (len >= nice_match) {
          break;
        }
        scan_end1  = _win[scan + best_len - 1];
        scan_end   = _win[scan + best_len];
      }
    } while ((cur_match = prev[cur_match & wmask]) > limit && --chain_length !== 0);

    if (best_len <= s.lookahead) {
      return best_len;
    }
    return s.lookahead;
  };


  /* ===========================================================================
   * Fill the window when the lookahead becomes insufficient.
   * Updates strstart and lookahead.
   *
   * IN assertion: lookahead < MIN_LOOKAHEAD
   * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
   *    At least one byte has been read, or avail_in == 0; reads are
   *    performed for at least two bytes (required for the zip translate_eol
   *    option -- not supported here).
   */
  const fill_window = (s) => {

    const _w_size = s.w_size;
    let n, more, str;

    //Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead");

    do {
      more = s.window_size - s.lookahead - s.strstart;

      // JS ints have 32 bit, block below not needed
      /* Deal with !@#$% 64K limit: */
      //if (sizeof(int) <= 2) {
      //    if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
      //        more = wsize;
      //
      //  } else if (more == (unsigned)(-1)) {
      //        /* Very unlikely, but possible on 16 bit machine if
      //         * strstart == 0 && lookahead == 1 (input done a byte at time)
      //         */
      //        more--;
      //    }
      //}


      /* If the window is almost full and there is insufficient lookahead,
       * move the upper half to the lower one to make room in the upper half.
       */
      if (s.strstart >= _w_size + (_w_size - MIN_LOOKAHEAD)) {

        s.window.set(s.window.subarray(_w_size, _w_size + _w_size - more), 0);
        s.match_start -= _w_size;
        s.strstart -= _w_size;
        /* we now have strstart >= MAX_DIST */
        s.block_start -= _w_size;
        if (s.insert > s.strstart) {
          s.insert = s.strstart;
        }
        slide_hash(s);
        more += _w_size;
      }
      if (s.strm.avail_in === 0) {
        break;
      }

      /* If there was no sliding:
       *    strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
       *    more == window_size - lookahead - strstart
       * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
       * => more >= window_size - 2*WSIZE + 2
       * In the BIG_MEM or MMAP case (not yet supported),
       *   window_size == input_size + MIN_LOOKAHEAD  &&
       *   strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
       * Otherwise, window_size == 2*WSIZE so more >= 2.
       * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
       */
      //Assert(more >= 2, "more < 2");
      n = read_buf(s.strm, s.window, s.strstart + s.lookahead, more);
      s.lookahead += n;

      /* Initialize the hash value now that we have some input: */
      if (s.lookahead + s.insert >= MIN_MATCH) {
        str = s.strstart - s.insert;
        s.ins_h = s.window[str];

        /* UPDATE_HASH(s, s->ins_h, s->window[str + 1]); */
        s.ins_h = HASH(s, s.ins_h, s.window[str + 1]);
  //#if MIN_MATCH != 3
  //        Call update_hash() MIN_MATCH-3 more times
  //#endif
        while (s.insert) {
          /* UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]); */
          s.ins_h = HASH(s, s.ins_h, s.window[str + MIN_MATCH - 1]);

          s.prev[str & s.w_mask] = s.head[s.ins_h];
          s.head[s.ins_h] = str;
          str++;
          s.insert--;
          if (s.lookahead + s.insert < MIN_MATCH) {
            break;
          }
        }
      }
      /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
       * but this is not important since only literal bytes will be emitted.
       */

    } while (s.lookahead < MIN_LOOKAHEAD && s.strm.avail_in !== 0);

    /* If the WIN_INIT bytes after the end of the current data have never been
     * written, then zero those bytes in order to avoid memory check reports of
     * the use of uninitialized (or uninitialised as Julian writes) bytes by
     * the longest match routines.  Update the high water mark for the next
     * time through here.  WIN_INIT is set to MAX_MATCH since the longest match
     * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead.
     */
  //  if (s.high_water < s.window_size) {
  //    const curr = s.strstart + s.lookahead;
  //    let init = 0;
  //
  //    if (s.high_water < curr) {
  //      /* Previous high water mark below current data -- zero WIN_INIT
  //       * bytes or up to end of window, whichever is less.
  //       */
  //      init = s.window_size - curr;
  //      if (init > WIN_INIT)
  //        init = WIN_INIT;
  //      zmemzero(s->window + curr, (unsigned)init);
  //      s->high_water = curr + init;
  //    }
  //    else if (s->high_water < (ulg)curr + WIN_INIT) {
  //      /* High water mark at or above current data, but below current data
  //       * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up
  //       * to end of window, whichever is less.
  //       */
  //      init = (ulg)curr + WIN_INIT - s->high_water;
  //      if (init > s->window_size - s->high_water)
  //        init = s->window_size - s->high_water;
  //      zmemzero(s->window + s->high_water, (unsigned)init);
  //      s->high_water += init;
  //    }
  //  }
  //
  //  Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD,
  //    "not enough room for search");
  };

  /* ===========================================================================
   * Copy without compression as much as possible from the input stream, return
   * the current block state.
   *
   * In case deflateParams() is used to later switch to a non-zero compression
   * level, s->matches (otherwise unused when storing) keeps track of the number
   * of hash table slides to perform. If s->matches is 1, then one hash table
   * slide will be done when switching. If s->matches is 2, the maximum value
   * allowed here, then the hash table will be cleared, since two or more slides
   * is the same as a clear.
   *
   * deflate_stored() is written to minimize the number of times an input byte is
   * copied. It is most efficient with large input and output buffers, which
   * maximizes the opportunites to have a single copy from next_in to next_out.
   */
  const deflate_stored = (s, flush) => {

    /* Smallest worthy block size when not flushing or finishing. By default
     * this is 32K. This can be as small as 507 bytes for memLevel == 1. For
     * large input and output buffers, the stored block size will be larger.
     */
    let min_block = s.pending_buf_size - 5 > s.w_size ? s.w_size : s.pending_buf_size - 5;

    /* Copy as many min_block or larger stored blocks directly to next_out as
     * possible. If flushing, copy the remaining available input to next_out as
     * stored blocks, if there is enough space.
     */
    let len, left, have, last = 0;
    let used = s.strm.avail_in;
    do {
      /* Set len to the maximum size block that we can copy directly with the
       * available input data and output space. Set left to how much of that
       * would be copied from what's left in the window.
       */
      len = 65535/* MAX_STORED */;     /* maximum deflate stored block length */
      have = (s.bi_valid + 42) >> 3;     /* number of header bytes */
      if (s.strm.avail_out < have) {         /* need room for header */
        break;
      }
        /* maximum stored block length that will fit in avail_out: */
      have = s.strm.avail_out - have;
      left = s.strstart - s.block_start;  /* bytes left in window */
      if (len > left + s.strm.avail_in) {
        len = left + s.strm.avail_in;   /* limit len to the input */
      }
      if (len > have) {
        len = have;             /* limit len to the output */
      }

      /* If the stored block would be less than min_block in length, or if
       * unable to copy all of the available input when flushing, then try
       * copying to the window and the pending buffer instead. Also don't
       * write an empty block when flushing -- deflate() does that.
       */
      if (len < min_block && ((len === 0 && flush !== Z_FINISH$1) ||
                          flush === Z_NO_FLUSH$1 ||
                          len !== left + s.strm.avail_in)) {
        break;
      }

      /* Make a dummy stored block in pending to get the header bytes,
       * including any pending bits. This also updates the debugging counts.
       */
      last = flush === Z_FINISH$1 && len === left + s.strm.avail_in ? 1 : 0;
      _tr_stored_block(s, 0, 0, last);

      /* Replace the lengths in the dummy stored block with len. */
      s.pending_buf[s.pending - 4] = len;
      s.pending_buf[s.pending - 3] = len >> 8;
      s.pending_buf[s.pending - 2] = ~len;
      s.pending_buf[s.pending - 1] = ~len >> 8;

      /* Write the stored block header bytes. */
      flush_pending(s.strm);

  //#ifdef ZLIB_DEBUG
  //    /* Update debugging counts for the data about to be copied. */
  //    s->compressed_len += len << 3;
  //    s->bits_sent += len << 3;
  //#endif

      /* Copy uncompressed bytes from the window to next_out. */
      if (left) {
        if (left > len) {
          left = len;
        }
        //zmemcpy(s->strm->next_out, s->window + s->block_start, left);
        s.strm.output.set(s.window.subarray(s.block_start, s.block_start + left), s.strm.next_out);
        s.strm.next_out += left;
        s.strm.avail_out -= left;
        s.strm.total_out += left;
        s.block_start += left;
        len -= left;
      }

      /* Copy uncompressed bytes directly from next_in to next_out, updating
       * the check value.
       */
      if (len) {
        read_buf(s.strm, s.strm.output, s.strm.next_out, len);
        s.strm.next_out += len;
        s.strm.avail_out -= len;
        s.strm.total_out += len;
      }
    } while (last === 0);

    /* Update the sliding window with the last s->w_size bytes of the copied
     * data, or append all of the copied data to the existing window if less
     * than s->w_size bytes were copied. Also update the number of bytes to
     * insert in the hash tables, in the event that deflateParams() switches to
     * a non-zero compression level.
     */
    used -= s.strm.avail_in;    /* number of input bytes directly copied */
    if (used) {
      /* If any input was used, then no unused input remains in the window,
       * therefore s->block_start == s->strstart.
       */
      if (used >= s.w_size) {  /* supplant the previous history */
        s.matches = 2;     /* clear hash */
        //zmemcpy(s->window, s->strm->next_in - s->w_size, s->w_size);
        s.window.set(s.strm.input.subarray(s.strm.next_in - s.w_size, s.strm.next_in), 0);
        s.strstart = s.w_size;
        s.insert = s.strstart;
      }
      else {
        if (s.window_size - s.strstart <= used) {
          /* Slide the window down. */
          s.strstart -= s.w_size;
          //zmemcpy(s->window, s->window + s->w_size, s->strstart);
          s.window.set(s.window.subarray(s.w_size, s.w_size + s.strstart), 0);
          if (s.matches < 2) {
            s.matches++;   /* add a pending slide_hash() */
          }
          if (s.insert > s.strstart) {
            s.insert = s.strstart;
          }
        }
        //zmemcpy(s->window + s->strstart, s->strm->next_in - used, used);
        s.window.set(s.strm.input.subarray(s.strm.next_in - used, s.strm.next_in), s.strstart);
        s.strstart += used;
        s.insert += used > s.w_size - s.insert ? s.w_size - s.insert : used;
      }
      s.block_start = s.strstart;
    }
    if (s.high_water < s.strstart) {
      s.high_water = s.strstart;
    }

    /* If the last block was written to next_out, then done. */
    if (last) {
      return BS_FINISH_DONE;
    }

    /* If flushing and all input has been consumed, then done. */
    if (flush !== Z_NO_FLUSH$1 && flush !== Z_FINISH$1 &&
      s.strm.avail_in === 0 && s.strstart === s.block_start) {
      return BS_BLOCK_DONE;
    }

    /* Fill the window with any remaining input. */
    have = s.window_size - s.strstart;
    if (s.strm.avail_in > have && s.block_start >= s.w_size) {
      /* Slide the window down. */
      s.block_start -= s.w_size;
      s.strstart -= s.w_size;
      //zmemcpy(s->window, s->window + s->w_size, s->strstart);
      s.window.set(s.window.subarray(s.w_size, s.w_size + s.strstart), 0);
      if (s.matches < 2) {
        s.matches++;       /* add a pending slide_hash() */
      }
      have += s.w_size;      /* more space now */
      if (s.insert > s.strstart) {
        s.insert = s.strstart;
      }
    }
    if (have > s.strm.avail_in) {
      have = s.strm.avail_in;
    }
    if (have) {
      read_buf(s.strm, s.window, s.strstart, have);
      s.strstart += have;
      s.insert += have > s.w_size - s.insert ? s.w_size - s.insert : have;
    }
    if (s.high_water < s.strstart) {
      s.high_water = s.strstart;
    }

    /* There was not enough avail_out to write a complete worthy or flushed
     * stored block to next_out. Write a stored block to pending instead, if we
     * have enough input for a worthy block, or if flushing and there is enough
     * room for the remaining input as a stored block in the pending buffer.
     */
    have = (s.bi_valid + 42) >> 3;     /* number of header bytes */
      /* maximum stored block length that will fit in pending: */
    have = s.pending_buf_size - have > 65535/* MAX_STORED */ ? 65535/* MAX_STORED */ : s.pending_buf_size - have;
    min_block = have > s.w_size ? s.w_size : have;
    left = s.strstart - s.block_start;
    if (left >= min_block ||
       ((left || flush === Z_FINISH$1) && flush !== Z_NO_FLUSH$1 &&
       s.strm.avail_in === 0 && left <= have)) {
      len = left > have ? have : left;
      last = flush === Z_FINISH$1 && s.strm.avail_in === 0 &&
           len === left ? 1 : 0;
      _tr_stored_block(s, s.block_start, len, last);
      s.block_start += len;
      flush_pending(s.strm);
    }

    /* We've done all we can with the available input and output. */
    return last ? BS_FINISH_STARTED : BS_NEED_MORE;
  };


  /* ===========================================================================
   * Compress as much as possible from the input stream, return the current
   * block state.
   * This function does not perform lazy evaluation of matches and inserts
   * new strings in the dictionary only for unmatched strings or for short
   * matches. It is used only for the fast compression options.
   */
  const deflate_fast = (s, flush) => {

    let hash_head;        /* head of the hash chain */
    let bflush;           /* set if current block must be flushed */

    for (;;) {
      /* Make sure that we always have enough lookahead, except
       * at the end of the input file. We need MAX_MATCH bytes
       * for the next match, plus MIN_MATCH bytes to insert the
       * string following the next match.
       */
      if (s.lookahead < MIN_LOOKAHEAD) {
        fill_window(s);
        if (s.lookahead < MIN_LOOKAHEAD && flush === Z_NO_FLUSH$1) {
          return BS_NEED_MORE;
        }
        if (s.lookahead === 0) {
          break; /* flush the current block */
        }
      }

      /* Insert the string window[strstart .. strstart+2] in the
       * dictionary, and set hash_head to the head of the hash chain:
       */
      hash_head = 0/*NIL*/;
      if (s.lookahead >= MIN_MATCH) {
        /*** INSERT_STRING(s, s.strstart, hash_head); ***/
        s.ins_h = HASH(s, s.ins_h, s.window[s.strstart + MIN_MATCH - 1]);
        hash_head = s.prev[s.strstart & s.w_mask] = s.head[s.ins_h];
        s.head[s.ins_h] = s.strstart;
        /***/
      }

      /* Find the longest match, discarding those <= prev_length.
       * At this point we have always match_length < MIN_MATCH
       */
      if (hash_head !== 0/*NIL*/ && ((s.strstart - hash_head) <= (s.w_size - MIN_LOOKAHEAD))) {
        /* To simplify the code, we prevent matches with the string
         * of window index 0 (in particular we have to avoid a match
         * of the string with itself at the start of the input file).
         */
        s.match_length = longest_match(s, hash_head);
        /* longest_match() sets match_start */
      }
      if (s.match_length >= MIN_MATCH) {
        // check_match(s, s.strstart, s.match_start, s.match_length); // for debug only

        /*** _tr_tally_dist(s, s.strstart - s.match_start,
                       s.match_length - MIN_MATCH, bflush); ***/
        bflush = _tr_tally(s, s.strstart - s.match_start, s.match_length - MIN_MATCH);

        s.lookahead -= s.match_length;

        /* Insert new strings in the hash table only if the match length
         * is not too large. This saves time but degrades compression.
         */
        if (s.match_length <= s.max_lazy_match/*max_insert_length*/ && s.lookahead >= MIN_MATCH) {
          s.match_length--; /* string at strstart already in table */
          do {
            s.strstart++;
            /*** INSERT_STRING(s, s.strstart, hash_head); ***/
            s.ins_h = HASH(s, s.ins_h, s.window[s.strstart + MIN_MATCH - 1]);
            hash_head = s.prev[s.strstart & s.w_mask] = s.head[s.ins_h];
            s.head[s.ins_h] = s.strstart;
            /***/
            /* strstart never exceeds WSIZE-MAX_MATCH, so there are
             * always MIN_MATCH bytes ahead.
             */
          } while (--s.match_length !== 0);
          s.strstart++;
        } else
        {
          s.strstart += s.match_length;
          s.match_length = 0;
          s.ins_h = s.window[s.strstart];
          /* UPDATE_HASH(s, s.ins_h, s.window[s.strstart+1]); */
          s.ins_h = HASH(s, s.ins_h, s.window[s.strstart + 1]);

  //#if MIN_MATCH != 3
  //                Call UPDATE_HASH() MIN_MATCH-3 more times
  //#endif
          /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
           * matter since it will be recomputed at next deflate call.
           */
        }
      } else {
        /* No match, output a literal byte */
        //Tracevv((stderr,"%c", s.window[s.strstart]));
        /*** _tr_tally_lit(s, s.window[s.strstart], bflush); ***/
        bflush = _tr_tally(s, 0, s.window[s.strstart]);

        s.lookahead--;
        s.strstart++;
      }
      if (bflush) {
        /*** FLUSH_BLOCK(s, 0); ***/
        flush_block_only(s, false);
        if (s.strm.avail_out === 0) {
          return BS_NEED_MORE;
        }
        /***/
      }
    }
    s.insert = ((s.strstart < (MIN_MATCH - 1)) ? s.strstart : MIN_MATCH - 1);
    if (flush === Z_FINISH$1) {
      /*** FLUSH_BLOCK(s, 1); ***/
      flush_block_only(s, true);
      if (s.strm.avail_out === 0) {
        return BS_FINISH_STARTED;
      }
      /***/
      return BS_FINISH_DONE;
    }
    if (s.sym_next) {
      /*** FLUSH_BLOCK(s, 0); ***/
      flush_block_only(s, false);
      if (s.strm.avail_out === 0) {
        return BS_NEED_MORE;
      }
      /***/
    }
    return BS_BLOCK_DONE;
  };

  /* ===========================================================================
   * Same as above, but achieves better compression. We use a lazy
   * evaluation for matches: a match is finally adopted only if there is
   * no better match at the next window position.
   */
  const deflate_slow = (s, flush) => {

    let hash_head;          /* head of hash chain */
    let bflush;              /* set if current block must be flushed */

    let max_insert;

    /* Process the input block. */
    for (;;) {
      /* Make sure that we always have enough lookahead, except
       * at the end of the input file. We need MAX_MATCH bytes
       * for the next match, plus MIN_MATCH bytes to insert the
       * string following the next match.
       */
      if (s.lookahead < MIN_LOOKAHEAD) {
        fill_window(s);
        if (s.lookahead < MIN_LOOKAHEAD && flush === Z_NO_FLUSH$1) {
          return BS_NEED_MORE;
        }
        if (s.lookahead === 0) { break; } /* flush the current block */
      }

      /* Insert the string window[strstart .. strstart+2] in the
       * dictionary, and set hash_head to the head of the hash chain:
       */
      hash_head = 0/*NIL*/;
      if (s.lookahead >= MIN_MATCH) {
        /*** INSERT_STRING(s, s.strstart, hash_head); ***/
        s.ins_h = HASH(s, s.ins_h, s.window[s.strstart + MIN_MATCH - 1]);
        hash_head = s.prev[s.strstart & s.w_mask] = s.head[s.ins_h];
        s.head[s.ins_h] = s.strstart;
        /***/
      }

      /* Find the longest match, discarding those <= prev_length.
       */
      s.prev_length = s.match_length;
      s.prev_match = s.match_start;
      s.match_length = MIN_MATCH - 1;

      if (hash_head !== 0/*NIL*/ && s.prev_length < s.max_lazy_match &&
          s.strstart - hash_head <= (s.w_size - MIN_LOOKAHEAD)/*MAX_DIST(s)*/) {
        /* To simplify the code, we prevent matches with the string
         * of window index 0 (in particular we have to avoid a match
         * of the string with itself at the start of the input file).
         */
        s.match_length = longest_match(s, hash_head);
        /* longest_match() sets match_start */

        if (s.match_length <= 5 &&
           (s.strategy === Z_FILTERED || (s.match_length === MIN_MATCH && s.strstart - s.match_start > 4096/*TOO_FAR*/))) {

          /* If prev_match is also MIN_MATCH, match_start is garbage
           * but we will ignore the current match anyway.
           */
          s.match_length = MIN_MATCH - 1;
        }
      }
      /* If there was a match at the previous step and the current
       * match is not better, output the previous match:
       */
      if (s.prev_length >= MIN_MATCH && s.match_length <= s.prev_length) {
        max_insert = s.strstart + s.lookahead - MIN_MATCH;
        /* Do not insert strings in hash table beyond this. */

        //check_match(s, s.strstart-1, s.prev_match, s.prev_length);

        /***_tr_tally_dist(s, s.strstart - 1 - s.prev_match,
                       s.prev_length - MIN_MATCH, bflush);***/
        bflush = _tr_tally(s, s.strstart - 1 - s.prev_match, s.prev_length - MIN_MATCH);
        /* Insert in hash table all strings up to the end of the match.
         * strstart-1 and strstart are already inserted. If there is not
         * enough lookahead, the last two strings are not inserted in
         * the hash table.
         */
        s.lookahead -= s.prev_length - 1;
        s.prev_length -= 2;
        do {
          if (++s.strstart <= max_insert) {
            /*** INSERT_STRING(s, s.strstart, hash_head); ***/
            s.ins_h = HASH(s, s.ins_h, s.window[s.strstart + MIN_MATCH - 1]);
            hash_head = s.prev[s.strstart & s.w_mask] = s.head[s.ins_h];
            s.head[s.ins_h] = s.strstart;
            /***/
          }
        } while (--s.prev_length !== 0);
        s.match_available = 0;
        s.match_length = MIN_MATCH - 1;
        s.strstart++;

        if (bflush) {
          /*** FLUSH_BLOCK(s, 0); ***/
          flush_block_only(s, false);
          if (s.strm.avail_out === 0) {
            return BS_NEED_MORE;
          }
          /***/
        }

      } else if (s.match_available) {
        /* If there was no match at the previous position, output a
         * single literal. If there was a match but the current match
         * is longer, truncate the previous match to a single literal.
         */
        //Tracevv((stderr,"%c", s->window[s->strstart-1]));
        /*** _tr_tally_lit(s, s.window[s.strstart-1], bflush); ***/
        bflush = _tr_tally(s, 0, s.window[s.strstart - 1]);

        if (bflush) {
          /*** FLUSH_BLOCK_ONLY(s, 0) ***/
          flush_block_only(s, false);
          /***/
        }
        s.strstart++;
        s.lookahead--;
        if (s.strm.avail_out === 0) {
          return BS_NEED_MORE;
        }
      } else {
        /* There is no previous match to compare with, wait for
         * the next step to decide.
         */
        s.match_available = 1;
        s.strstart++;
        s.lookahead--;
      }
    }
    //Assert (flush != Z_NO_FLUSH, "no flush?");
    if (s.match_available) {
      //Tracevv((stderr,"%c", s->window[s->strstart-1]));
      /*** _tr_tally_lit(s, s.window[s.strstart-1], bflush); ***/
      bflush = _tr_tally(s, 0, s.window[s.strstart - 1]);

      s.match_available = 0;
    }
    s.insert = s.strstart < MIN_MATCH - 1 ? s.strstart : MIN_MATCH - 1;
    if (flush === Z_FINISH$1) {
      /*** FLUSH_BLOCK(s, 1); ***/
      flush_block_only(s, true);
      if (s.strm.avail_out === 0) {
        return BS_FINISH_STARTED;
      }
      /***/
      return BS_FINISH_DONE;
    }
    if (s.sym_next) {
      /*** FLUSH_BLOCK(s, 0); ***/
      flush_block_only(s, false);
      if (s.strm.avail_out === 0) {
        return BS_NEED_MORE;
      }
      /***/
    }

    return BS_BLOCK_DONE;
  };


  /* ===========================================================================
   * For Z_RLE, simply look for runs of bytes, generate matches only of distance
   * one.  Do not maintain a hash table.  (It will be regenerated if this run of
   * deflate switches away from Z_RLE.)
   */
  const deflate_rle = (s, flush) => {

    let bflush;            /* set if current block must be flushed */
    let prev;              /* byte at distance one to match */
    let scan, strend;      /* scan goes up to strend for length of run */

    const _win = s.window;

    for (;;) {
      /* Make sure that we always have enough lookahead, except
       * at the end of the input file. We need MAX_MATCH bytes
       * for the longest run, plus one for the unrolled loop.
       */
      if (s.lookahead <= MAX_MATCH) {
        fill_window(s);
        if (s.lookahead <= MAX_MATCH && flush === Z_NO_FLUSH$1) {
          return BS_NEED_MORE;
        }
        if (s.lookahead === 0) { break; } /* flush the current block */
      }

      /* See how many times the previous byte repeats */
      s.match_length = 0;
      if (s.lookahead >= MIN_MATCH && s.strstart > 0) {
        scan = s.strstart - 1;
        prev = _win[scan];
        if (prev === _win[++scan] && prev === _win[++scan] && prev === _win[++scan]) {
          strend = s.strstart + MAX_MATCH;
          do {
            /*jshint noempty:false*/
          } while (prev === _win[++scan] && prev === _win[++scan] &&
                   prev === _win[++scan] && prev === _win[++scan] &&
                   prev === _win[++scan] && prev === _win[++scan] &&
                   prev === _win[++scan] && prev === _win[++scan] &&
                   scan < strend);
          s.match_length = MAX_MATCH - (strend - scan);
          if (s.match_length > s.lookahead) {
            s.match_length = s.lookahead;
          }
        }
        //Assert(scan <= s->window+(uInt)(s->window_size-1), "wild scan");
      }

      /* Emit match if have run of MIN_MATCH or longer, else emit literal */
      if (s.match_length >= MIN_MATCH) {
        //check_match(s, s.strstart, s.strstart - 1, s.match_length);

        /*** _tr_tally_dist(s, 1, s.match_length - MIN_MATCH, bflush); ***/
        bflush = _tr_tally(s, 1, s.match_length - MIN_MATCH);

        s.lookahead -= s.match_length;
        s.strstart += s.match_length;
        s.match_length = 0;
      } else {
        /* No match, output a literal byte */
        //Tracevv((stderr,"%c", s->window[s->strstart]));
        /*** _tr_tally_lit(s, s.window[s.strstart], bflush); ***/
        bflush = _tr_tally(s, 0, s.window[s.strstart]);

        s.lookahead--;
        s.strstart++;
      }
      if (bflush) {
        /*** FLUSH_BLOCK(s, 0); ***/
        flush_block_only(s, false);
        if (s.strm.avail_out === 0) {
          return BS_NEED_MORE;
        }
        /***/
      }
    }
    s.insert = 0;
    if (flush === Z_FINISH$1) {
      /*** FLUSH_BLOCK(s, 1); ***/
      flush_block_only(s, true);
      if (s.strm.avail_out === 0) {
        return BS_FINISH_STARTED;
      }
      /***/
      return BS_FINISH_DONE;
    }
    if (s.sym_next) {
      /*** FLUSH_BLOCK(s, 0); ***/
      flush_block_only(s, false);
      if (s.strm.avail_out === 0) {
        return BS_NEED_MORE;
      }
      /***/
    }
    return BS_BLOCK_DONE;
  };

  /* ===========================================================================
   * For Z_HUFFMAN_ONLY, do not look for matches.  Do not maintain a hash table.
   * (It will be regenerated if this run of deflate switches away from Huffman.)
   */
  const deflate_huff = (s, flush) => {

    let bflush;             /* set if current block must be flushed */

    for (;;) {
      /* Make sure that we have a literal to write. */
      if (s.lookahead === 0) {
        fill_window(s);
        if (s.lookahead === 0) {
          if (flush === Z_NO_FLUSH$1) {
            return BS_NEED_MORE;
          }
          break;      /* flush the current block */
        }
      }

      /* Output a literal byte */
      s.match_length = 0;
      //Tracevv((stderr,"%c", s->window[s->strstart]));
      /*** _tr_tally_lit(s, s.window[s.strstart], bflush); ***/
      bflush = _tr_tally(s, 0, s.window[s.strstart]);
      s.lookahead--;
      s.strstart++;
      if (bflush) {
        /*** FLUSH_BLOCK(s, 0); ***/
        flush_block_only(s, false);
        if (s.strm.avail_out === 0) {
          return BS_NEED_MORE;
        }
        /***/
      }
    }
    s.insert = 0;
    if (flush === Z_FINISH$1) {
      /*** FLUSH_BLOCK(s, 1); ***/
      flush_block_only(s, true);
      if (s.strm.avail_out === 0) {
        return BS_FINISH_STARTED;
      }
      /***/
      return BS_FINISH_DONE;
    }
    if (s.sym_next) {
      /*** FLUSH_BLOCK(s, 0); ***/
      flush_block_only(s, false);
      if (s.strm.avail_out === 0) {
        return BS_NEED_MORE;
      }
      /***/
    }
    return BS_BLOCK_DONE;
  };

  /* Values for max_lazy_match, good_match and max_chain_length, depending on
   * the desired pack level (0..9). The values given below have been tuned to
   * exclude worst case performance for pathological files. Better values may be
   * found for specific files.
   */
  function Config(good_length, max_lazy, nice_length, max_chain, func) {

    this.good_length = good_length;
    this.max_lazy = max_lazy;
    this.nice_length = nice_length;
    this.max_chain = max_chain;
    this.func = func;
  }

  const configuration_table = [
    /*      good lazy nice chain */
    new Config(0, 0, 0, 0, deflate_stored),          /* 0 store only */
    new Config(4, 4, 8, 4, deflate_fast),            /* 1 max speed, no lazy matches */
    new Config(4, 5, 16, 8, deflate_fast),           /* 2 */
    new Config(4, 6, 32, 32, deflate_fast),          /* 3 */

    new Config(4, 4, 16, 16, deflate_slow),          /* 4 lazy matches */
    new Config(8, 16, 32, 32, deflate_slow),         /* 5 */
    new Config(8, 16, 128, 128, deflate_slow),       /* 6 */
    new Config(8, 32, 128, 256, deflate_slow),       /* 7 */
    new Config(32, 128, 258, 1024, deflate_slow),    /* 8 */
    new Config(32, 258, 258, 4096, deflate_slow)     /* 9 max compression */
  ];


  /* ===========================================================================
   * Initialize the "longest match" routines for a new zlib stream
   */
  const lm_init = (s) => {

    s.window_size = 2 * s.w_size;

    /*** CLEAR_HASH(s); ***/
    zero(s.head); // Fill with NIL (= 0);

    /* Set the default configuration parameters:
     */
    s.max_lazy_match = configuration_table[s.level].max_lazy;
    s.good_match = configuration_table[s.level].good_length;
    s.nice_match = configuration_table[s.level].nice_length;
    s.max_chain_length = configuration_table[s.level].max_chain;

    s.strstart = 0;
    s.block_start = 0;
    s.lookahead = 0;
    s.insert = 0;
    s.match_length = s.prev_length = MIN_MATCH - 1;
    s.match_available = 0;
    s.ins_h = 0;
  };


  function DeflateState() {
    this.strm = null;            /* pointer back to this zlib stream */
    this.status = 0;            /* as the name implies */
    this.pending_buf = null;      /* output still pending */
    this.pending_buf_size = 0;  /* size of pending_buf */
    this.pending_out = 0;       /* next pending byte to output to the stream */
    this.pending = 0;           /* nb of bytes in the pending buffer */
    this.wrap = 0;              /* bit 0 true for zlib, bit 1 true for gzip */
    this.gzhead = null;         /* gzip header information to write */
    this.gzindex = 0;           /* where in extra, name, or comment */
    this.method = Z_DEFLATED$1; /* can only be DEFLATED */
    this.last_flush = -1;   /* value of flush param for previous deflate call */

    this.w_size = 0;  /* LZ77 window size (32K by default) */
    this.w_bits = 0;  /* log2(w_size)  (8..16) */
    this.w_mask = 0;  /* w_size - 1 */

    this.window = null;
    /* Sliding window. Input bytes are read into the second half of the window,
     * and move to the first half later to keep a dictionary of at least wSize
     * bytes. With this organization, matches are limited to a distance of
     * wSize-MAX_MATCH bytes, but this ensures that IO is always
     * performed with a length multiple of the block size.
     */

    this.window_size = 0;
    /* Actual size of window: 2*wSize, except when the user input buffer
     * is directly used as sliding window.
     */

    this.prev = null;
    /* Link to older string with same hash index. To limit the size of this
     * array to 64K, this link is maintained only for the last 32K strings.
     * An index in this array is thus a window index modulo 32K.
     */

    this.head = null;   /* Heads of the hash chains or NIL. */

    this.ins_h = 0;       /* hash index of string to be inserted */
    this.hash_size = 0;   /* number of elements in hash table */
    this.hash_bits = 0;   /* log2(hash_size) */
    this.hash_mask = 0;   /* hash_size-1 */

    this.hash_shift = 0;
    /* Number of bits by which ins_h must be shifted at each input
     * step. It must be such that after MIN_MATCH steps, the oldest
     * byte no longer takes part in the hash key, that is:
     *   hash_shift * MIN_MATCH >= hash_bits
     */

    this.block_start = 0;
    /* Window position at the beginning of the current output block. Gets
     * negative when the window is moved backwards.
     */

    this.match_length = 0;      /* length of best match */
    this.prev_match = 0;        /* previous match */
    this.match_available = 0;   /* set if previous match exists */
    this.strstart = 0;          /* start of string to insert */
    this.match_start = 0;       /* start of matching string */
    this.lookahead = 0;         /* number of valid bytes ahead in window */

    this.prev_length = 0;
    /* Length of the best match at previous step. Matches not greater than this
     * are discarded. This is used in the lazy match evaluation.
     */

    this.max_chain_length = 0;
    /* To speed up deflation, hash chains are never searched beyond this
     * length.  A higher limit improves compression ratio but degrades the
     * speed.
     */

    this.max_lazy_match = 0;
    /* Attempt to find a better match only when the current match is strictly
     * smaller than this value. This mechanism is used only for compression
     * levels >= 4.
     */
    // That's alias to max_lazy_match, don't use directly
    //this.max_insert_length = 0;
    /* Insert new strings in the hash table only if the match length is not
     * greater than this length. This saves time but degrades compression.
     * max_insert_length is used only for compression levels <= 3.
     */

    this.level = 0;     /* compression level (1..9) */
    this.strategy = 0;  /* favor or force Huffman coding*/

    this.good_match = 0;
    /* Use a faster search when the previous match is longer than this */

    this.nice_match = 0; /* Stop searching when current match exceeds this */

                /* used by trees.c: */

    /* Didn't use ct_data typedef below to suppress compiler warning */

    // struct ct_data_s dyn_ltree[HEAP_SIZE];   /* literal and length tree */
    // struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
    // struct ct_data_s bl_tree[2*BL_CODES+1];  /* Huffman tree for bit lengths */

    // Use flat array of DOUBLE size, with interleaved fata,
    // because JS does not support effective
    this.dyn_ltree  = new Uint16Array(HEAP_SIZE * 2);
    this.dyn_dtree  = new Uint16Array((2 * D_CODES + 1) * 2);
    this.bl_tree    = new Uint16Array((2 * BL_CODES + 1) * 2);
    zero(this.dyn_ltree);
    zero(this.dyn_dtree);
    zero(this.bl_tree);

    this.l_desc   = null;         /* desc. for literal tree */
    this.d_desc   = null;         /* desc. for distance tree */
    this.bl_desc  = null;         /* desc. for bit length tree */

    //ush bl_count[MAX_BITS+1];
    this.bl_count = new Uint16Array(MAX_BITS + 1);
    /* number of codes at each bit length for an optimal tree */

    //int heap[2*L_CODES+1];      /* heap used to build the Huffman trees */
    this.heap = new Uint16Array(2 * L_CODES + 1);  /* heap used to build the Huffman trees */
    zero(this.heap);

    this.heap_len = 0;               /* number of elements in the heap */
    this.heap_max = 0;               /* element of largest frequency */
    /* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
     * The same heap array is used to build all trees.
     */

    this.depth = new Uint16Array(2 * L_CODES + 1); //uch depth[2*L_CODES+1];
    zero(this.depth);
    /* Depth of each subtree used as tie breaker for trees of equal frequency
     */

    this.sym_buf = 0;        /* buffer for distances and literals/lengths */

    this.lit_bufsize = 0;
    /* Size of match buffer for literals/lengths.  There are 4 reasons for
     * limiting lit_bufsize to 64K:
     *   - frequencies can be kept in 16 bit counters
     *   - if compression is not successful for the first block, all input
     *     data is still in the window so we can still emit a stored block even
     *     when input comes from standard input.  (This can also be done for
     *     all blocks if lit_bufsize is not greater than 32K.)
     *   - if compression is not successful for a file smaller than 64K, we can
     *     even emit a stored file instead of a stored block (saving 5 bytes).
     *     This is applicable only for zip (not gzip or zlib).
     *   - creating new Huffman trees less frequently may not provide fast
     *     adaptation to changes in the input data statistics. (Take for
     *     example a binary file with poorly compressible code followed by
     *     a highly compressible string table.) Smaller buffer sizes give
     *     fast adaptation but have of course the overhead of transmitting
     *     trees more frequently.
     *   - I can't count above 4
     */

    this.sym_next = 0;      /* running index in sym_buf */
    this.sym_end = 0;       /* symbol table full when sym_next reaches this */

    this.opt_len = 0;       /* bit length of current block with optimal trees */
    this.static_len = 0;    /* bit length of current block with static trees */
    this.matches = 0;       /* number of string matches in current block */
    this.insert = 0;        /* bytes at end of window left to insert */


    this.bi_buf = 0;
    /* Output buffer. bits are inserted starting at the bottom (least
     * significant bits).
     */
    this.bi_valid = 0;
    /* Number of valid bits in bi_buf.  All bits above the last valid bit
     * are always zero.
     */

    // Used for window memory init. We safely ignore it for JS. That makes
    // sense only for pointers and memory check tools.
    //this.high_water = 0;
    /* High water mark offset in window for initialized bytes -- bytes above
     * this are set to zero in order to avoid memory check warnings when
     * longest match routines access bytes past the input.  This is then
     * updated to the new high water mark.
     */
  }


  /* =========================================================================
   * Check for a valid deflate stream state. Return 0 if ok, 1 if not.
   */
  const deflateStateCheck = (strm) => {

    if (!strm) {
      return 1;
    }
    const s = strm.state;
    if (!s || s.strm !== strm || (s.status !== INIT_STATE &&
  //#ifdef GZIP
                                  s.status !== GZIP_STATE &&
  //#endif
                                  s.status !== EXTRA_STATE &&
                                  s.status !== NAME_STATE &&
                                  s.status !== COMMENT_STATE &&
                                  s.status !== HCRC_STATE &&
                                  s.status !== BUSY_STATE &&
                                  s.status !== FINISH_STATE)) {
      return 1;
    }
    return 0;
  };


  const deflateResetKeep = (strm) => {

    if (deflateStateCheck(strm)) {
      return err(strm, Z_STREAM_ERROR);
    }

    strm.total_in = strm.total_out = 0;
    strm.data_type = Z_UNKNOWN;

    const s = strm.state;
    s.pending = 0;
    s.pending_out = 0;

    if (s.wrap < 0) {
      s.wrap = -s.wrap;
      /* was made negative by deflate(..., Z_FINISH); */
    }
    s.status =
  //#ifdef GZIP
      s.wrap === 2 ? GZIP_STATE :
  //#endif
      s.wrap ? INIT_STATE : BUSY_STATE;
    strm.adler = (s.wrap === 2) ?
      0  // crc32(0, Z_NULL, 0)
    :
      1; // adler32(0, Z_NULL, 0)
    s.last_flush = -2;
    _tr_init(s);
    return Z_OK$1;
  };


  const deflateReset = (strm) => {

    const ret = deflateResetKeep(strm);
    if (ret === Z_OK$1) {
      lm_init(strm.state);
    }
    return ret;
  };


  const deflateSetHeader = (strm, head) => {

    if (deflateStateCheck(strm) || strm.state.wrap !== 2) {
      return Z_STREAM_ERROR;
    }
    strm.state.gzhead = head;
    return Z_OK$1;
  };


  const deflateInit2 = (strm, level, method, windowBits, memLevel, strategy) => {

    if (!strm) { // === Z_NULL
      return Z_STREAM_ERROR;
    }
    let wrap = 1;

    if (level === Z_DEFAULT_COMPRESSION$1) {
      level = 6;
    }

    if (windowBits < 0) { /* suppress zlib wrapper */
      wrap = 0;
      windowBits = -windowBits;
    }

    else if (windowBits > 15) {
      wrap = 2;           /* write gzip wrapper instead */
      windowBits -= 16;
    }


    if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method !== Z_DEFLATED$1 ||
      windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
      strategy < 0 || strategy > Z_FIXED || (windowBits === 8 && wrap !== 1)) {
      return err(strm, Z_STREAM_ERROR);
    }


    if (windowBits === 8) {
      windowBits = 9;
    }
    /* until 256-byte window bug fixed */

    const s = new DeflateState();

    strm.state = s;
    s.strm = strm;
    s.status = INIT_STATE;     /* to pass state test in deflateReset() */

    s.wrap = wrap;
    s.gzhead = null;
    s.w_bits = windowBits;
    s.w_size = 1 << s.w_bits;
    s.w_mask = s.w_size - 1;

    s.hash_bits = memLevel + 7;
    s.hash_size = 1 << s.hash_bits;
    s.hash_mask = s.hash_size - 1;
    s.hash_shift = ~~((s.hash_bits + MIN_MATCH - 1) / MIN_MATCH);

    s.window = new Uint8Array(s.w_size * 2);
    s.head = new Uint16Array(s.hash_size);
    s.prev = new Uint16Array(s.w_size);

    // Don't need mem init magic for JS.
    //s.high_water = 0;  /* nothing written to s->window yet */

    s.lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */

    /* We overlay pending_buf and sym_buf. This works since the average size
     * for length/distance pairs over any compressed block is assured to be 31
     * bits or less.
     *
     * Analysis: The longest fixed codes are a length code of 8 bits plus 5
     * extra bits, for lengths 131 to 257. The longest fixed distance codes are
     * 5 bits plus 13 extra bits, for distances 16385 to 32768. The longest
     * possible fixed-codes length/distance pair is then 31 bits total.
     *
     * sym_buf starts one-fourth of the way into pending_buf. So there are
     * three bytes in sym_buf for every four bytes in pending_buf. Each symbol
     * in sym_buf is three bytes -- two for the distance and one for the
     * literal/length. As each symbol is consumed, the pointer to the next
     * sym_buf value to read moves forward three bytes. From that symbol, up to
     * 31 bits are written to pending_buf. The closest the written pending_buf
     * bits gets to the next sym_buf symbol to read is just before the last
     * code is written. At that time, 31*(n-2) bits have been written, just
     * after 24*(n-2) bits have been consumed from sym_buf. sym_buf starts at
     * 8*n bits into pending_buf. (Note that the symbol buffer fills when n-1
     * symbols are written.) The closest the writing gets to what is unread is
     * then n+14 bits. Here n is lit_bufsize, which is 16384 by default, and
     * can range from 128 to 32768.
     *
     * Therefore, at a minimum, there are 142 bits of space between what is
     * written and what is read in the overlain buffers, so the symbols cannot
     * be overwritten by the compressed data. That space is actually 139 bits,
     * due to the three-bit fixed-code block header.
     *
     * That covers the case where either Z_FIXED is specified, forcing fixed
     * codes, or when the use of fixed codes is chosen, because that choice
     * results in a smaller compressed block than dynamic codes. That latter
     * condition then assures that the above analysis also covers all dynamic
     * blocks. A dynamic-code block will only be chosen to be emitted if it has
     * fewer bits than a fixed-code block would for the same set of symbols.
     * Therefore its average symbol length is assured to be less than 31. So
     * the compressed data for a dynamic block also cannot overwrite the
     * symbols from which it is being constructed.
     */

    s.pending_buf_size = s.lit_bufsize * 4;
    s.pending_buf = new Uint8Array(s.pending_buf_size);

    // It is offset from `s.pending_buf` (size is `s.lit_bufsize * 2`)
    //s->sym_buf = s->pending_buf + s->lit_bufsize;
    s.sym_buf = s.lit_bufsize;

    //s->sym_end = (s->lit_bufsize - 1) * 3;
    s.sym_end = (s.lit_bufsize - 1) * 3;
    /* We avoid equality with lit_bufsize*3 because of wraparound at 64K
     * on 16 bit machines and because stored blocks are restricted to
     * 64K-1 bytes.
     */

    s.level = level;
    s.strategy = strategy;
    s.method = method;

    return deflateReset(strm);
  };

  const deflateInit = (strm, level) => {

    return deflateInit2(strm, level, Z_DEFLATED$1, MAX_WBITS, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY$1);
  };


  /* ========================================================================= */
  const deflate$1 = (strm, flush) => {

    if (deflateStateCheck(strm) || flush > Z_BLOCK || flush < 0) {
      return strm ? err(strm, Z_STREAM_ERROR) : Z_STREAM_ERROR;
    }

    const s = strm.state;

    if (!strm.output ||
        (strm.avail_in !== 0 && !strm.input) ||
        (s.status === FINISH_STATE && flush !== Z_FINISH$1)) {
      return err(strm, (strm.avail_out === 0) ? Z_BUF_ERROR : Z_STREAM_ERROR);
    }

    const old_flush = s.last_flush;
    s.last_flush = flush;

    /* Flush as much pending output as possible */
    if (s.pending !== 0) {
      flush_pending(strm);
      if (strm.avail_out === 0) {
        /* Since avail_out is 0, deflate will be called again with
         * more output space, but possibly with both pending and
         * avail_in equal to zero. There won't be anything to do,
         * but this is not an error situation so make sure we
         * return OK instead of BUF_ERROR at next call of deflate:
         */
        s.last_flush = -1;
        return Z_OK$1;
      }

      /* Make sure there is something to do and avoid duplicate consecutive
       * flushes. For repeated and useless calls with Z_FINISH, we keep
       * returning Z_STREAM_END instead of Z_BUF_ERROR.
       */
    } else if (strm.avail_in === 0 && rank(flush) <= rank(old_flush) &&
      flush !== Z_FINISH$1) {
      return err(strm, Z_BUF_ERROR);
    }

    /* User must not provide more input after the first FINISH: */
    if (s.status === FINISH_STATE && strm.avail_in !== 0) {
      return err(strm, Z_BUF_ERROR);
    }

    /* Write the header */
    if (s.status === INIT_STATE && s.wrap === 0) {
      s.status = BUSY_STATE;
    }
    if (s.status === INIT_STATE) {
      /* zlib header */
      let header = (Z_DEFLATED$1 + ((s.w_bits - 8) << 4)) << 8;
      let level_flags = -1;

      if (s.strategy >= Z_HUFFMAN_ONLY || s.level < 2) {
        level_flags = 0;
      } else if (s.level < 6) {
        level_flags = 1;
      } else if (s.level === 6) {
        level_flags = 2;
      } else {
        level_flags = 3;
      }
      header |= (level_flags << 6);
      if (s.strstart !== 0) { header |= PRESET_DICT; }
      header += 31 - (header % 31);

      putShortMSB(s, header);

      /* Save the adler32 of the preset dictionary: */
      if (s.strstart !== 0) {
        putShortMSB(s, strm.adler >>> 16);
        putShortMSB(s, strm.adler & 0xffff);
      }
      strm.adler = 1; // adler32(0L, Z_NULL, 0);
      s.status = BUSY_STATE;

      /* Compression must start with an empty pending buffer */
      flush_pending(strm);
      if (s.pending !== 0) {
        s.last_flush = -1;
        return Z_OK$1;
      }
    }
  //#ifdef GZIP
    if (s.status === GZIP_STATE) {
      /* gzip header */
      strm.adler = 0;  //crc32(0L, Z_NULL, 0);
      put_byte(s, 31);
      put_byte(s, 139);
      put_byte(s, 8);
      if (!s.gzhead) { // s->gzhead == Z_NULL
        put_byte(s, 0);
        put_byte(s, 0);
        put_byte(s, 0);
        put_byte(s, 0);
        put_byte(s, 0);
        put_byte(s, s.level === 9 ? 2 :
                    (s.strategy >= Z_HUFFMAN_ONLY || s.level < 2 ?
                     4 : 0));
        put_byte(s, OS_CODE);
        s.status = BUSY_STATE;

        /* Compression must start with an empty pending buffer */
        flush_pending(strm);
        if (s.pending !== 0) {
          s.last_flush = -1;
          return Z_OK$1;
        }
      }
      else {
        put_byte(s, (s.gzhead.text ? 1 : 0) +
                    (s.gzhead.hcrc ? 2 : 0) +
                    (!s.gzhead.extra ? 0 : 4) +
                    (!s.gzhead.name ? 0 : 8) +
                    (!s.gzhead.comment ? 0 : 16)
        );
        put_byte(s, s.gzhead.time & 0xff);
        put_byte(s, (s.gzhead.time >> 8) & 0xff);
        put_byte(s, (s.gzhead.time >> 16) & 0xff);
        put_byte(s, (s.gzhead.time >> 24) & 0xff);
        put_byte(s, s.level === 9 ? 2 :
                    (s.strategy >= Z_HUFFMAN_ONLY || s.level < 2 ?
                     4 : 0));
        put_byte(s, s.gzhead.os & 0xff);
        if (s.gzhead.extra && s.gzhead.extra.length) {
          put_byte(s, s.gzhead.extra.length & 0xff);
          put_byte(s, (s.gzhead.extra.length >> 8) & 0xff);
        }
        if (s.gzhead.hcrc) {
          strm.adler = crc32_1(strm.adler, s.pending_buf, s.pending, 0);
        }
        s.gzindex = 0;
        s.status = EXTRA_STATE;
      }
    }
    if (s.status === EXTRA_STATE) {
      if (s.gzhead.extra/* != Z_NULL*/) {
        let beg = s.pending;   /* start of bytes to update crc */
        let left = (s.gzhead.extra.length & 0xffff) - s.gzindex;
        while (s.pending + left > s.pending_buf_size) {
          let copy = s.pending_buf_size - s.pending;
          // zmemcpy(s.pending_buf + s.pending,
          //    s.gzhead.extra + s.gzindex, copy);
          s.pending_buf.set(s.gzhead.extra.subarray(s.gzindex, s.gzindex + copy), s.pending);
          s.pending = s.pending_buf_size;
          //--- HCRC_UPDATE(beg) ---//
          if (s.gzhead.hcrc && s.pending > beg) {
            strm.adler = crc32_1(strm.adler, s.pending_buf, s.pending - beg, beg);
          }
          //---//
          s.gzindex += copy;
          flush_pending(strm);
          if (s.pending !== 0) {
            s.last_flush = -1;
            return Z_OK$1;
          }
          beg = 0;
          left -= copy;
        }
        // JS specific: s.gzhead.extra may be TypedArray or Array for backward compatibility
        //              TypedArray.slice and TypedArray.from don't exist in IE10-IE11
        let gzhead_extra = new Uint8Array(s.gzhead.extra);
        // zmemcpy(s->pending_buf + s->pending,
        //     s->gzhead->extra + s->gzindex, left);
        s.pending_buf.set(gzhead_extra.subarray(s.gzindex, s.gzindex + left), s.pending);
        s.pending += left;
        //--- HCRC_UPDATE(beg) ---//
        if (s.gzhead.hcrc && s.pending > beg) {
          strm.adler = crc32_1(strm.adler, s.pending_buf, s.pending - beg, beg);
        }
        //---//
        s.gzindex = 0;
      }
      s.status = NAME_STATE;
    }
    if (s.status === NAME_STATE) {
      if (s.gzhead.name/* != Z_NULL*/) {
        let beg = s.pending;   /* start of bytes to update crc */
        let val;
        do {
          if (s.pending === s.pending_buf_size) {
            //--- HCRC_UPDATE(beg) ---//
            if (s.gzhead.hcrc && s.pending > beg) {
              strm.adler = crc32_1(strm.adler, s.pending_buf, s.pending - beg, beg);
            }
            //---//
            flush_pending(strm);
            if (s.pending !== 0) {
              s.last_flush = -1;
              return Z_OK$1;
            }
            beg = 0;
          }
          // JS specific: little magic to add zero terminator to end of string
          if (s.gzindex < s.gzhead.name.length) {
            val = s.gzhead.name.charCodeAt(s.gzindex++) & 0xff;
          } else {
            val = 0;
          }
          put_byte(s, val);
        } while (val !== 0);
        //--- HCRC_UPDATE(beg) ---//
        if (s.gzhead.hcrc && s.pending > beg) {
          strm.adler = crc32_1(strm.adler, s.pending_buf, s.pending - beg, beg);
        }
        //---//
        s.gzindex = 0;
      }
      s.status = COMMENT_STATE;
    }
    if (s.status === COMMENT_STATE) {
      if (s.gzhead.comment/* != Z_NULL*/) {
        let beg = s.pending;   /* start of bytes to update crc */
        let val;
        do {
          if (s.pending === s.pending_buf_size) {
            //--- HCRC_UPDATE(beg) ---//
            if (s.gzhead.hcrc && s.pending > beg) {
              strm.adler = crc32_1(strm.adler, s.pending_buf, s.pending - beg, beg);
            }
            //---//
            flush_pending(strm);
            if (s.pending !== 0) {
              s.last_flush = -1;
              return Z_OK$1;
            }
            beg = 0;
          }
          // JS specific: little magic to add zero terminator to end of string
          if (s.gzindex < s.gzhead.comment.length) {
            val = s.gzhead.comment.charCodeAt(s.gzindex++) & 0xff;
          } else {
            val = 0;
          }
          put_byte(s, val);
        } while (val !== 0);
        //--- HCRC_UPDATE(beg) ---//
        if (s.gzhead.hcrc && s.pending > beg) {
          strm.adler = crc32_1(strm.adler, s.pending_buf, s.pending - beg, beg);
        }
        //---//
      }
      s.status = HCRC_STATE;
    }
    if (s.status === HCRC_STATE) {
      if (s.gzhead.hcrc) {
        if (s.pending + 2 > s.pending_buf_size) {
          flush_pending(strm);
          if (s.pending !== 0) {
            s.last_flush = -1;
            return Z_OK$1;
          }
        }
        put_byte(s, strm.adler & 0xff);
        put_byte(s, (strm.adler >> 8) & 0xff);
        strm.adler = 0; //crc32(0L, Z_NULL, 0);
      }
      s.status = BUSY_STATE;

      /* Compression must start with an empty pending buffer */
      flush_pending(strm);
      if (s.pending !== 0) {
        s.last_flush = -1;
        return Z_OK$1;
      }
    }
  //#endif

    /* Start a new block or continue the current one.
     */
    if (strm.avail_in !== 0 || s.lookahead !== 0 ||
      (flush !== Z_NO_FLUSH$1 && s.status !== FINISH_STATE)) {
      let bstate = s.level === 0 ? deflate_stored(s, flush) :
                   s.strategy === Z_HUFFMAN_ONLY ? deflate_huff(s, flush) :
                   s.strategy === Z_RLE ? deflate_rle(s, flush) :
                   configuration_table[s.level].func(s, flush);

      if (bstate === BS_FINISH_STARTED || bstate === BS_FINISH_DONE) {
        s.status = FINISH_STATE;
      }
      if (bstate === BS_NEED_MORE || bstate === BS_FINISH_STARTED) {
        if (strm.avail_out === 0) {
          s.last_flush = -1;
          /* avoid BUF_ERROR next call, see above */
        }
        return Z_OK$1;
        /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
         * of deflate should use the same flush parameter to make sure
         * that the flush is complete. So we don't have to output an
         * empty block here, this will be done at next call. This also
         * ensures that for a very small output buffer, we emit at most
         * one empty block.
         */
      }
      if (bstate === BS_BLOCK_DONE) {
        if (flush === Z_PARTIAL_FLUSH) {
          _tr_align(s);
        }
        else if (flush !== Z_BLOCK) { /* FULL_FLUSH or SYNC_FLUSH */

          _tr_stored_block(s, 0, 0, false);
          /* For a full flush, this empty block will be recognized
           * as a special marker by inflate_sync().
           */
          if (flush === Z_FULL_FLUSH$1) {
            /*** CLEAR_HASH(s); ***/             /* forget history */
            zero(s.head); // Fill with NIL (= 0);

            if (s.lookahead === 0) {
              s.strstart = 0;
              s.block_start = 0;
              s.insert = 0;
            }
          }
        }
        flush_pending(strm);
        if (strm.avail_out === 0) {
          s.last_flush = -1; /* avoid BUF_ERROR at next call, see above */
          return Z_OK$1;
        }
      }
    }

    if (flush !== Z_FINISH$1) { return Z_OK$1; }
    if (s.wrap <= 0) { return Z_STREAM_END$1; }

    /* Write the trailer */
    if (s.wrap === 2) {
      put_byte(s, strm.adler & 0xff);
      put_byte(s, (strm.adler >> 8) & 0xff);
      put_byte(s, (strm.adler >> 16) & 0xff);
      put_byte(s, (strm.adler >> 24) & 0xff);
      put_byte(s, strm.total_in & 0xff);
      put_byte(s, (strm.total_in >> 8) & 0xff);
      put_byte(s, (strm.total_in >> 16) & 0xff);
      put_byte(s, (strm.total_in >> 24) & 0xff);
    }
    else
    {
      putShortMSB(s, strm.adler >>> 16);
      putShortMSB(s, strm.adler & 0xffff);
    }

    flush_pending(strm);
    /* If avail_out is zero, the application will call deflate again
     * to flush the rest.
     */
    if (s.wrap > 0) { s.wrap = -s.wrap; }
    /* write the trailer only once! */
    return s.pending !== 0 ? Z_OK$1 : Z_STREAM_END$1;
  };


  const deflateEnd = (strm) => {

    if (deflateStateCheck(strm)) {
      return Z_STREAM_ERROR;
    }

    const status = strm.state.status;

    strm.state = null;

    return status === BUSY_STATE ? err(strm, Z_DATA_ERROR) : Z_OK$1;
  };


  /* =========================================================================
   * Initializes the compression dictionary from the given byte
   * sequence without producing any compressed output.
   */
  const deflateSetDictionary = (strm, dictionary) => {

    let dictLength = dictionary.length;

    if (deflateStateCheck(strm)) {
      return Z_STREAM_ERROR;
    }

    const s = strm.state;
    const wrap = s.wrap;

    if (wrap === 2 || (wrap === 1 && s.status !== INIT_STATE) || s.lookahead) {
      return Z_STREAM_ERROR;
    }

    /* when using zlib wrappers, compute Adler-32 for provided dictionary */
    if (wrap === 1) {
      /* adler32(strm->adler, dictionary, dictLength); */
      strm.adler = adler32_1(strm.adler, dictionary, dictLength, 0);
    }

    s.wrap = 0;   /* avoid computing Adler-32 in read_buf */

    /* if dictionary would fill window, just replace the history */
    if (dictLength >= s.w_size) {
      if (wrap === 0) {            /* already empty otherwise */
        /*** CLEAR_HASH(s); ***/
        zero(s.head); // Fill with NIL (= 0);
        s.strstart = 0;
        s.block_start = 0;
        s.insert = 0;
      }
      /* use the tail */
      // dictionary = dictionary.slice(dictLength - s.w_size);
      let tmpDict = new Uint8Array(s.w_size);
      tmpDict.set(dictionary.subarray(dictLength - s.w_size, dictLength), 0);
      dictionary = tmpDict;
      dictLength = s.w_size;
    }
    /* insert dictionary into window and hash */
    const avail = strm.avail_in;
    const next = strm.next_in;
    const input = strm.input;
    strm.avail_in = dictLength;
    strm.next_in = 0;
    strm.input = dictionary;
    fill_window(s);
    while (s.lookahead >= MIN_MATCH) {
      let str = s.strstart;
      let n = s.lookahead - (MIN_MATCH - 1);
      do {
        /* UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]); */
        s.ins_h = HASH(s, s.ins_h, s.window[str + MIN_MATCH - 1]);

        s.prev[str & s.w_mask] = s.head[s.ins_h];

        s.head[s.ins_h] = str;
        str++;
      } while (--n);
      s.strstart = str;
      s.lookahead = MIN_MATCH - 1;
      fill_window(s);
    }
    s.strstart += s.lookahead;
    s.block_start = s.strstart;
    s.insert = s.lookahead;
    s.lookahead = 0;
    s.match_length = s.prev_length = MIN_MATCH - 1;
    s.match_available = 0;
    strm.next_in = next;
    strm.input = input;
    strm.avail_in = avail;
    s.wrap = wrap;
    return Z_OK$1;
  };


  var deflateInit_1 = deflateInit;
  var deflateInit2_1 = deflateInit2;
  var deflateReset_1 = deflateReset;
  var deflateResetKeep_1 = deflateResetKeep;
  var deflateSetHeader_1 = deflateSetHeader;
  var deflate_2$1 = deflate$1;
  var deflateEnd_1 = deflateEnd;
  var deflateSetDictionary_1 = deflateSetDictionary;
  var deflateInfo = 'pako deflate (from Nodeca project)';

  /* Not implemented
  module.exports.deflateBound = deflateBound;
  module.exports.deflateCopy = deflateCopy;
  module.exports.deflateGetDictionary = deflateGetDictionary;
  module.exports.deflateParams = deflateParams;
  module.exports.deflatePending = deflatePending;
  module.exports.deflatePrime = deflatePrime;
  module.exports.deflateTune = deflateTune;
  */

  var deflate_1$1 = {
      deflateInit: deflateInit_1,
      deflateInit2: deflateInit2_1,
      deflateReset: deflateReset_1,
      deflateResetKeep: deflateResetKeep_1,
      deflateSetHeader: deflateSetHeader_1,
      deflate: deflate_2$1,
      deflateEnd: deflateEnd_1,
      deflateSetDictionary: deflateSetDictionary_1,
      deflateInfo: deflateInfo
  };

  const _has = (obj, key) => {
    return Object.prototype.hasOwnProperty.call(obj, key);
  };

  var assign = function (obj /*from1, from2, from3, ...*/) {
    const sources = Array.prototype.slice.call(arguments, 1);
    while (sources.length) {
      const source = sources.shift();
      if (!source) { continue; }

      if (typeof source !== 'object') {
        throw new TypeError(source + 'must be non-object');
      }

      for (const p in source) {
        if (_has(source, p)) {
          obj[p] = source[p];
        }
      }
    }

    return obj;
  };


  // Join array of chunks to single array.
  var flattenChunks = (chunks) => {
    // calculate data length
    let len = 0;

    for (let i = 0, l = chunks.length; i < l; i++) {
      len += chunks[i].length;
    }

    // join chunks
    const result = new Uint8Array(len);

    for (let i = 0, pos = 0, l = chunks.length; i < l; i++) {
      let chunk = chunks[i];
      result.set(chunk, pos);
      pos += chunk.length;
    }

    return result;
  };

  var common = {
      assign: assign,
      flattenChunks: flattenChunks
  };

  // String encode/decode helpers


  // Quick check if we can use fast array to bin string conversion
  //
  // - apply(Array) can fail on Android 2.2
  // - apply(Uint8Array) can fail on iOS 5.1 Safari
  //
  let STR_APPLY_UIA_OK = true;

  try { String.fromCharCode.apply(null, new Uint8Array(1)); } catch (__) { STR_APPLY_UIA_OK = false; }


  // Table with utf8 lengths (calculated by first byte of sequence)
  // Note, that 5 & 6-byte values and some 4-byte values can not be represented in JS,
  // because max possible codepoint is 0x10ffff
  const _utf8len = new Uint8Array(256);
  for (let q = 0; q < 256; q++) {
    _utf8len[q] = (q >= 252 ? 6 : q >= 248 ? 5 : q >= 240 ? 4 : q >= 224 ? 3 : q >= 192 ? 2 : 1);
  }
  _utf8len[254] = _utf8len[254] = 1; // Invalid sequence start


  // convert string to array (typed, when possible)
  var string2buf = (str) => {
    if (typeof TextEncoder === 'function' && TextEncoder.prototype.encode) {
      return new TextEncoder().encode(str);
    }

    let buf, c, c2, m_pos, i, str_len = str.length, buf_len = 0;

    // count binary size
    for (m_pos = 0; m_pos < str_len; m_pos++) {
      c = str.charCodeAt(m_pos);
      if ((c & 0xfc00) === 0xd800 && (m_pos + 1 < str_len)) {
        c2 = str.charCodeAt(m_pos + 1);
        if ((c2 & 0xfc00) === 0xdc00) {
          c = 0x10000 + ((c - 0xd800) << 10) + (c2 - 0xdc00);
          m_pos++;
        }
      }
      buf_len += c < 0x80 ? 1 : c < 0x800 ? 2 : c < 0x10000 ? 3 : 4;
    }

    // allocate buffer
    buf = new Uint8Array(buf_len);

    // convert
    for (i = 0, m_pos = 0; i < buf_len; m_pos++) {
      c = str.charCodeAt(m_pos);
      if ((c & 0xfc00) === 0xd800 && (m_pos + 1 < str_len)) {
        c2 = str.charCodeAt(m_pos + 1);
        if ((c2 & 0xfc00) === 0xdc00) {
          c = 0x10000 + ((c - 0xd800) << 10) + (c2 - 0xdc00);
          m_pos++;
        }
      }
      if (c < 0x80) {
        /* one byte */
        buf[i++] = c;
      } else if (c < 0x800) {
        /* two bytes */
        buf[i++] = 0xC0 | (c >>> 6);
        buf[i++] = 0x80 | (c & 0x3f);
      } else if (c < 0x10000) {
        /* three bytes */
        buf[i++] = 0xE0 | (c >>> 12);
        buf[i++] = 0x80 | (c >>> 6 & 0x3f);
        buf[i++] = 0x80 | (c & 0x3f);
      } else {
        /* four bytes */
        buf[i++] = 0xf0 | (c >>> 18);
        buf[i++] = 0x80 | (c >>> 12 & 0x3f);
        buf[i++] = 0x80 | (c >>> 6 & 0x3f);
        buf[i++] = 0x80 | (c & 0x3f);
      }
    }

    return buf;
  };

  // Helper
  const buf2binstring = (buf, len) => {
    // On Chrome, the arguments in a function call that are allowed is `65534`.
    // If the length of the buffer is smaller than that, we can use this optimization,
    // otherwise we will take a slower path.
    if (len < 65534) {
      if (buf.subarray && STR_APPLY_UIA_OK) {
        return String.fromCharCode.apply(null, buf.length === len ? buf : buf.subarray(0, len));
      }
    }

    let result = '';
    for (let i = 0; i < len; i++) {
      result += String.fromCharCode(buf[i]);
    }
    return result;
  };


  // convert array to string
  var buf2string = (buf, max) => {
    const len = max || buf.length;

    if (typeof TextDecoder === 'function' && TextDecoder.prototype.decode) {
      return new TextDecoder().decode(buf.subarray(0, max));
    }

    let i, out;

    // Reserve max possible length (2 words per char)
    // NB: by unknown reasons, Array is significantly faster for
    //     String.fromCharCode.apply than Uint16Array.
    const utf16buf = new Array(len * 2);

    for (out = 0, i = 0; i < len;) {
      let c = buf[i++];
      // quick process ascii
      if (c < 0x80) { utf16buf[out++] = c; continue; }

      let c_len = _utf8len[c];
      // skip 5 & 6 byte codes
      if (c_len > 4) { utf16buf[out++] = 0xfffd; i += c_len - 1; continue; }

      // apply mask on first byte
      c &= c_len === 2 ? 0x1f : c_len === 3 ? 0x0f : 0x07;
      // join the rest
      while (c_len > 1 && i < len) {
        c = (c << 6) | (buf[i++] & 0x3f);
        c_len--;
      }

      // terminated by end of string?
      if (c_len > 1) { utf16buf[out++] = 0xfffd; continue; }

      if (c < 0x10000) {
        utf16buf[out++] = c;
      } else {
        c -= 0x10000;
        utf16buf[out++] = 0xd800 | ((c >> 10) & 0x3ff);
        utf16buf[out++] = 0xdc00 | (c & 0x3ff);
      }
    }

    return buf2binstring(utf16buf, out);
  };


  // Calculate max possible position in utf8 buffer,
  // that will not break sequence. If that's not possible
  // - (very small limits) return max size as is.
  //
  // buf[] - utf8 bytes array
  // max   - length limit (mandatory);
  var utf8border = (buf, max) => {

    max = max || buf.length;
    if (max > buf.length) { max = buf.length; }

    // go back from last position, until start of sequence found
    let pos = max - 1;
    while (pos >= 0 && (buf[pos] & 0xC0) === 0x80) { pos--; }

    // Very small and broken sequence,
    // return max, because we should return something anyway.
    if (pos < 0) { return max; }

    // If we came to start of buffer - that means buffer is too small,
    // return max too.
    if (pos === 0) { return max; }

    return (pos + _utf8len[buf[pos]] > max) ? pos : max;
  };

  var strings = {
      string2buf: string2buf,
      buf2string: buf2string,
      utf8border: utf8border
  };

  // (C) 1995-2013 Jean-loup Gailly and Mark Adler
  // (C) 2014-2017 Vitaly Puzrin and Andrey Tupitsin
  //
  // This software is provided 'as-is', without any express or implied
  // warranty. In no event will the authors be held liable for any damages
  // arising from the use of this software.
  //
  // Permission is granted to anyone to use this software for any purpose,
  // including commercial applications, and to alter it and redistribute it
  // freely, subject to the following restrictions:
  //
  // 1. The origin of this software must not be misrepresented; you must not
  //   claim that you wrote the original software. If you use this software
  //   in a product, an acknowledgment in the product documentation would be
  //   appreciated but is not required.
  // 2. Altered source versions must be plainly marked as such, and must not be
  //   misrepresented as being the original software.
  // 3. This notice may not be removed or altered from any source distribution.

  function ZStream() {
    /* next input byte */
    this.input = null; // JS specific, because we have no pointers
    this.next_in = 0;
    /* number of bytes available at input */
    this.avail_in = 0;
    /* total number of input bytes read so far */
    this.total_in = 0;
    /* next output byte should be put there */
    this.output = null; // JS specific, because we have no pointers
    this.next_out = 0;
    /* remaining free space at output */
    this.avail_out = 0;
    /* total number of bytes output so far */
    this.total_out = 0;
    /* last error message, NULL if no error */
    this.msg = ''/*Z_NULL*/;
    /* not visible by applications */
    this.state = null;
    /* best guess about the data type: binary or text */
    this.data_type = 2/*Z_UNKNOWN*/;
    /* adler32 value of the uncompressed data */
    this.adler = 0;
  }

  var zstream = ZStream;

  const toString = Object.prototype.toString;

  /* Public constants ==========================================================*/
  /* ===========================================================================*/

  const {
    Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FULL_FLUSH, Z_FINISH,
    Z_OK, Z_STREAM_END,
    Z_DEFAULT_COMPRESSION,
    Z_DEFAULT_STRATEGY,
    Z_DEFLATED
  } = constants$1;

  /* ===========================================================================*/


  /**
   * class Deflate
   *
   * Generic JS-style wrapper for zlib calls. If you don't need
   * streaming behaviour - use more simple functions: [[deflate]],
   * [[deflateRaw]] and [[gzip]].
   **/

  /* internal
   * Deflate.chunks -> Array
   *
   * Chunks of output data, if [[Deflate#onData]] not overridden.
   **/

  /**
   * Deflate.result -> Uint8Array
   *
   * Compressed result, generated by default [[Deflate#onData]]
   * and [[Deflate#onEnd]] handlers. Filled after you push last chunk
   * (call [[Deflate#push]] with `Z_FINISH` / `true` param).
   **/

  /**
   * Deflate.err -> Number
   *
   * Error code after deflate finished. 0 (Z_OK) on success.
   * You will not need it in real life, because deflate errors
   * are possible only on wrong options or bad `onData` / `onEnd`
   * custom handlers.
   **/

  /**
   * Deflate.msg -> String
   *
   * Error message, if [[Deflate.err]] != 0
   **/


  /**
   * new Deflate(options)
   * - options (Object): zlib deflate options.
   *
   * Creates new deflator instance with specified params. Throws exception
   * on bad params. Supported options:
   *
   * - `level`
   * - `windowBits`
   * - `memLevel`
   * - `strategy`
   * - `dictionary`
   *
   * [http://zlib.net/manual.html#Advanced](http://zlib.net/manual.html#Advanced)
   * for more information on these.
   *
   * Additional options, for internal needs:
   *
   * - `chunkSize` - size of generated data chunks (16K by default)
   * - `raw` (Boolean) - do raw deflate
   * - `gzip` (Boolean) - create gzip wrapper
   * - `header` (Object) - custom header for gzip
   *   - `text` (Boolean) - true if compressed data believed to be text
   *   - `time` (Number) - modification time, unix timestamp
   *   - `os` (Number) - operation system code
   *   - `extra` (Array) - array of bytes with extra data (max 65536)
   *   - `name` (String) - file name (binary string)
   *   - `comment` (String) - comment (binary string)
   *   - `hcrc` (Boolean) - true if header crc should be added
   *
   * ##### Example:
   *
   * ```javascript
   * const pako = require('pako')
   *   , chunk1 = new Uint8Array([1,2,3,4,5,6,7,8,9])
   *   , chunk2 = new Uint8Array([10,11,12,13,14,15,16,17,18,19]);
   *
   * const deflate = new pako.Deflate({ level: 3});
   *
   * deflate.push(chunk1, false);
   * deflate.push(chunk2, true);  // true -> last chunk
   *
   * if (deflate.err) { throw new Error(deflate.err); }
   *
   * console.log(deflate.result);
   * ```
   **/
  function Deflate(options) {
    this.options = common.assign({
      level: Z_DEFAULT_COMPRESSION,
      method: Z_DEFLATED,
      chunkSize: 16384,
      windowBits: 15,
      memLevel: 8,
      strategy: Z_DEFAULT_STRATEGY
    }, options || {});

    let 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.err    = 0;      // error code, if happens (0 = Z_OK)
    this.msg    = '';     // error message
    this.ended  = false;  // used to avoid multiple onEnd() calls
    this.chunks = [];     // chunks of compressed data

    this.strm = new zstream();
    this.strm.avail_out = 0;

    let status = deflate_1$1.deflateInit2(
      this.strm,
      opt.level,
      opt.method,
      opt.windowBits,
      opt.memLevel,
      opt.strategy
    );

    if (status !== Z_OK) {
      throw new Error(messages[status]);
    }

    if (opt.header) {
      deflate_1$1.deflateSetHeader(this.strm, opt.header);
    }

    if (opt.dictionary) {
      let dict;
      // Convert data if needed
      if (typeof opt.dictionary === 'string') {
        // If we need to compress text, change encoding to utf8.
        dict = strings.string2buf(opt.dictionary);
      } else if (toString.call(opt.dictionary) === '[object ArrayBuffer]') {
        dict = new Uint8Array(opt.dictionary);
      } else {
        dict = opt.dictionary;
      }

      status = deflate_1$1.deflateSetDictionary(this.strm, dict);

      if (status !== Z_OK) {
        throw new Error(messages[status]);
      }

      this._dict_set = true;
    }
  }

  /**
   * Deflate#push(data[, flush_mode]) -> Boolean
   * - data (Uint8Array|ArrayBuffer|String): input data. Strings will be
   *   converted to utf8 byte sequence.
   * - flush_mode (Number|Boolean): 0..6 for corresponding Z_NO_FLUSH..Z_TREE modes.
   *   See constants. Skipped or `false` means Z_NO_FLUSH, `true` means Z_FINISH.
   *
   * Sends input data to deflate pipe, generating [[Deflate#onData]] calls with
   * new compressed chunks. Returns `true` on success. The last data block must
   * have `flush_mode` Z_FINISH (or `true`). That will flush internal pending
   * buffers and call [[Deflate#onEnd]].
   *
   * On fail call [[Deflate#onEnd]] with error code and return false.
   *
   * ##### Example
   *
   * ```javascript
   * push(chunk, false); // push one of data chunks
   * ...
   * push(chunk, true);  // push last chunk
   * ```
   **/
  Deflate.prototype.push = function (data, flush_mode) {
    const strm = this.strm;
    const chunkSize = this.options.chunkSize;
    let status, _flush_mode;

    if (this.ended) { return false; }

    if (flush_mode === ~~flush_mode) _flush_mode = flush_mode;
    else _flush_mode = flush_mode === true ? Z_FINISH : Z_NO_FLUSH;

    // Convert data if needed
    if (typeof data === 'string') {
      // If we need to compress text, change encoding to utf8.
      strm.input = strings.string2buf(data);
    } else if (toString.call(data) === '[object ArrayBuffer]') {
      strm.input = new Uint8Array(data);
    } else {
      strm.input = data;
    }

    strm.next_in = 0;
    strm.avail_in = strm.input.length;

    for (;;) {
      if (strm.avail_out === 0) {
        strm.output = new Uint8Array(chunkSize);
        strm.next_out = 0;
        strm.avail_out = chunkSize;
      }

      // Make sure avail_out > 6 to avoid repeating markers
      if ((_flush_mode === Z_SYNC_FLUSH || _flush_mode === Z_FULL_FLUSH) && strm.avail_out <= 6) {
        this.onData(strm.output.subarray(0, strm.next_out));
        strm.avail_out = 0;
        continue;
      }

      status = deflate_1$1.deflate(strm, _flush_mode);

      // Ended => flush and finish
      if (status === Z_STREAM_END) {
        if (strm.next_out > 0) {
          this.onData(strm.output.subarray(0, strm.next_out));
        }
        status = deflate_1$1.deflateEnd(this.strm);
        this.onEnd(status);
        this.ended = true;
        return status === Z_OK;
      }

      // Flush if out buffer full
      if (strm.avail_out === 0) {
        this.onData(strm.output);
        continue;
      }

      // Flush if requested and has data
      if (_flush_mode > 0 && strm.next_out > 0) {
        this.onData(strm.output.subarray(0, strm.next_out));
        strm.avail_out = 0;
        continue;
      }

      if (strm.avail_in === 0) break;
    }

    return true;
  };


  /**
   * Deflate#onData(chunk) -> Void
   * - chunk (Uint8Array): output data.
   *
   * By default, stores data blocks in `chunks[]` property and glue
   * those in `onEnd`. Override this handler, if you need another behaviour.
   **/
  Deflate.prototype.onData = function (chunk) {
    this.chunks.push(chunk);
  };


  /**
   * Deflate#onEnd(status) -> Void
   * - status (Number): deflate status. 0 (Z_OK) on success,
   *   other if not.
   *
   * Called once after you tell deflate that the input stream is
   * complete (Z_FINISH). By default - join collected chunks,
   * free memory and fill `results` / `err` properties.
   **/
  Deflate.prototype.onEnd = function (status) {
    // On success - join
    if (status === Z_OK) {
      this.result = common.flattenChunks(this.chunks);
    }
    this.chunks = [];
    this.err = status;
    this.msg = this.strm.msg;
  };


  /**
   * deflate(data[, options]) -> Uint8Array
   * - data (Uint8Array|ArrayBuffer|String): input data to compress.
   * - options (Object): zlib deflate options.
   *
   * Compress `data` with deflate algorithm and `options`.
   *
   * Supported options are:
   *
   * - level
   * - windowBits
   * - memLevel
   * - strategy
   * - dictionary
   *
   * [http://zlib.net/manual.html#Advanced](http://zlib.net/manual.html#Advanced)
   * for more information on these.
   *
   * Sugar (options):
   *
   * - `raw` (Boolean) - say that we work with raw stream, if you don't wish to specify
   *   negative windowBits implicitly.
   *
   * ##### Example:
   *
   * ```javascript
   * const pako = require('pako')
   * const data = new Uint8Array([1,2,3,4,5,6,7,8,9]);
   *
   * console.log(pako.deflate(data));
   * ```
   **/
  function deflate(input, options) {
    const deflator = new Deflate(options);

    deflator.push(input, true);

    // That will never happens, if you don't cheat with options :)
    if (deflator.err) { throw deflator.msg || messages[deflator.err]; }

    return deflator.result;
  }


  /**
   * deflateRaw(data[, options]) -> Uint8Array
   * - data (Uint8Array|ArrayBuffer|String): input data to compress.
   * - options (Object): zlib deflate options.
   *
   * The same as [[deflate]], but creates raw data, without wrapper
   * (header and adler32 crc).
   **/
  function deflateRaw(input, options) {
    options = options || {};
    options.raw = true;
    return deflate(input, options);
  }


  /**
   * gzip(data[, options]) -> Uint8Array
   * - data (Uint8Array|ArrayBuffer|String): input data to compress.
   * - options (Object): zlib deflate options.
   *
   * The same as [[deflate]], but create gzip wrapper instead of
   * deflate one.
   **/
  function gzip(input, options) {
    options = options || {};
    options.gzip = true;
    return deflate(input, options);
  }


  var Deflate_1 = Deflate;
  var deflate_2 = deflate;
  var deflateRaw_1 = deflateRaw;
  var gzip_1 = gzip;
  var constants = constants$1;

  var deflate_1 = {
      Deflate: Deflate_1,
      deflate: deflate_2,
      deflateRaw: deflateRaw_1,
      gzip: gzip_1,
      constants: constants
  };

  exports.Deflate = Deflate_1;
  exports.constants = constants;
  exports["default"] = deflate_1;
  exports.deflate = deflate_2;
  exports.deflateRaw = deflateRaw_1;
  exports.gzip = gzip_1;

  Object.defineProperty(exports, '__esModule', { value: true });

}));