'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.

import adler32 from './adler32.js'
import crc32 from './crc32.js'
import inflate_fast from './inffast.js'
import inflate_table from './inftrees.js'

const CODES = 0
const LENS = 1
const DISTS = 2

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

import {
  Z_FINISH,
  Z_BLOCK,
  Z_TREES,
  Z_OK,
  Z_STREAM_END,
  Z_NEED_DICT,
  Z_STREAM_ERROR,
  Z_DATA_ERROR,
  Z_MEM_ERROR,
  Z_BUF_ERROR,
  Z_DEFLATED
} from './constants.js'

/* STATES ====================================================================*/
/* ===========================================================================*/

const HEAD = 16180 /* i: waiting for magic header */
const FLAGS = 16181 /* i: waiting for method and flags (gzip) */
const TIME = 16182 /* i: waiting for modification time (gzip) */
const OS = 16183 /* i: waiting for extra flags and operating system (gzip) */
const EXLEN = 16184 /* i: waiting for extra length (gzip) */
const EXTRA = 16185 /* i: waiting for extra bytes (gzip) */
const NAME = 16186 /* i: waiting for end of file name (gzip) */
const COMMENT = 16187 /* i: waiting for end of comment (gzip) */
const HCRC = 16188 /* i: waiting for header crc (gzip) */
const DICTID = 16189 /* i: waiting for dictionary check value */
const DICT = 16190 /* waiting for inflateSetDictionary() call */
const TYPE = 16191 /* i: waiting for type bits, including last-flag bit */
const TYPEDO = 16192 /* i: same, but skip check to exit inflate on new block */
const STORED = 16193 /* i: waiting for stored size (length and complement) */
const COPY_ = 16194 /* i/o: same as COPY below, but only first time in */
const COPY = 16195 /* i/o: waiting for input or output to copy stored block */
const TABLE = 16196 /* i: waiting for dynamic block table lengths */
const LENLENS = 16197 /* i: waiting for code length code lengths */
const CODELENS = 16198 /* i: waiting for length/lit and distance code lengths */
const LEN_ = 16199 /* i: same as LEN below, but only first time in */
const LEN = 16200 /* i: waiting for length/lit/eob code */
const LENEXT = 16201 /* i: waiting for length extra bits */
const DIST = 16202 /* i: waiting for distance code */
const DISTEXT = 16203 /* i: waiting for distance extra bits */
const MATCH = 16204 /* o: waiting for output space to copy string */
const LIT = 16205 /* o: waiting for output space to write literal */
const CHECK = 16206 /* i: waiting for 32-bit check value */
const LENGTH = 16207 /* i: waiting for 32-bit length (gzip) */
const DONE = 16208 /* finished check, done -- remain here until reset */
const BAD = 16209 /* got a data error -- remain here until reset */
const MEM = 16210 /* got an inflate() memory error -- remain here until reset */
const SYNC = 16211 /* looking for synchronization bytes to restart inflate() */

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

const ENOUGH_LENS = 852
const ENOUGH_DISTS = 592
//const ENOUGH =  (ENOUGH_LENS+ENOUGH_DISTS);

const MAX_WBITS = 15
/* 32K LZ77 window */
const DEF_WBITS = MAX_WBITS

const zswap32 = q => {
  return (
    ((q >>> 24) & 0xff) +
    ((q >>> 8) & 0xff00) +
    ((q & 0xff00) << 8) +
    ((q & 0xff) << 24)
  )
}

function InflateState() {
  this.strm = null /* pointer back to this zlib stream */
  this.mode = 0 /* current inflate mode */
  this.last = false /* true if processing last block */
  this.wrap = 0 /* bit 0 true for zlib, bit 1 true for gzip,
                                 bit 2 true to validate check value */
  this.havedict = false /* true if dictionary provided */
  this.flags = 0 /* gzip header method and flags (0 if zlib), or
                                 -1 if raw or no header yet */
  this.dmax = 0 /* zlib header max distance (INFLATE_STRICT) */
  this.check = 0 /* protected copy of check value */
  this.total = 0 /* protected copy of output count */
  // TODO: may be {}
  this.head = null /* where to save gzip header information */

  /* sliding window */
  this.wbits = 0 /* log base 2 of requested window size */
  this.wsize = 0 /* window size or zero if not using window */
  this.whave = 0 /* valid bytes in the window */
  this.wnext = 0 /* window write index */
  this.window = null /* allocated sliding window, if needed */

  /* bit accumulator */
  this.hold = 0 /* input bit accumulator */
  this.bits = 0 /* number of bits in "in" */

  /* for string and stored block copying */
  this.length = 0 /* literal or length of data to copy */
  this.offset = 0 /* distance back to copy string from */

  /* for table and code decoding */
  this.extra = 0 /* extra bits needed */

  /* fixed and dynamic code tables */
  this.lencode = null /* starting table for length/literal codes */
  this.distcode = null /* starting table for distance codes */
  this.lenbits = 0 /* index bits for lencode */
  this.distbits = 0 /* index bits for distcode */

  /* dynamic table building */
  this.ncode = 0 /* number of code length code lengths */
  this.nlen = 0 /* number of length code lengths */
  this.ndist = 0 /* number of distance code lengths */
  this.have = 0 /* number of code lengths in lens[] */
  this.next = null /* next available space in codes[] */

  this.lens = new Uint16Array(320) /* temporary storage for code lengths */
  this.work = new Uint16Array(288) /* work area for code table building */

  /*
   because we don't have pointers in js, we use lencode and distcode directly
   as buffers so we don't need codes
  */
  //this.codes = new Int32Array(ENOUGH);       /* space for code tables */
  this.lendyn = null /* dynamic table for length/literal codes (JS specific) */
  this.distdyn = null /* dynamic table for distance codes (JS specific) */
  this.sane = 0 /* if false, allow invalid distance too far */
  this.back = 0 /* bits back of last unprocessed length/lit */
  this.was = 0 /* initial length of match */
}

const inflateStateCheck = strm => {
  if (!strm) {
    return 1
  }
  const state = strm.state
  if (!state || state.strm !== strm || state.mode < HEAD || state.mode > SYNC) {
    return 1
  }
  return 0
}

const inflateResetKeep = strm => {
  if (inflateStateCheck(strm)) {
    return Z_STREAM_ERROR
  }
  const state = strm.state
  strm.total_in = strm.total_out = state.total = 0
  strm.msg = '' /*Z_NULL*/
  if (state.wrap) {
    /* to support ill-conceived Java test suite */
    strm.adler = state.wrap & 1
  }
  state.mode = HEAD
  state.last = 0
  state.havedict = 0
  state.flags = -1
  state.dmax = 32768
  state.head = null /*Z_NULL*/
  state.hold = 0
  state.bits = 0
  //state.lencode = state.distcode = state.next = state.codes;
  state.lencode = state.lendyn = new Int32Array(ENOUGH_LENS)
  state.distcode = state.distdyn = new Int32Array(ENOUGH_DISTS)

  state.sane = 1
  state.back = -1
  //Tracev((stderr, "inflate: reset\n"));
  return Z_OK
}

const inflateReset = strm => {
  if (inflateStateCheck(strm)) {
    return Z_STREAM_ERROR
  }
  const state = strm.state
  state.wsize = 0
  state.whave = 0
  state.wnext = 0
  return inflateResetKeep(strm)
}

const inflateReset2 = (strm, windowBits) => {
  let wrap

  /* get the state */
  if (inflateStateCheck(strm)) {
    return Z_STREAM_ERROR
  }
  const state = strm.state

  /* extract wrap request from windowBits parameter */
  if (windowBits < 0) {
    wrap = 0
    windowBits = -windowBits
  } else {
    wrap = (windowBits >> 4) + 5
    if (windowBits < 48) {
      windowBits &= 15
    }
  }

  /* set number of window bits, free window if different */
  if (windowBits && (windowBits < 8 || windowBits > 15)) {
    return Z_STREAM_ERROR
  }
  if (state.window !== null && state.wbits !== windowBits) {
    state.window = null
  }

  /* update state and reset the rest of it */
  state.wrap = wrap
  state.wbits = windowBits
  return inflateReset(strm)
}

const inflateInit2 = (strm, windowBits) => {
  if (!strm) {
    return Z_STREAM_ERROR
  }
  //strm.msg = Z_NULL;                 /* in case we return an error */

  const state = new InflateState()

  //if (state === Z_NULL) return Z_MEM_ERROR;
  //Tracev((stderr, "inflate: allocated\n"));
  strm.state = state
  state.strm = strm
  state.window = null /*Z_NULL*/
  state.mode = HEAD /* to pass state test in inflateReset2() */
  const ret = inflateReset2(strm, windowBits)
  if (ret !== Z_OK) {
    strm.state = null /*Z_NULL*/
  }
  return ret
}

const inflateInit = strm => {
  return inflateInit2(strm, DEF_WBITS)
}

/*
 Return state with length and distance decoding tables and index sizes set to
 fixed code decoding.  Normally this returns fixed tables from inffixed.h.
 If BUILDFIXED is defined, then instead this routine builds the tables the
 first time it's called, and returns those tables the first time and
 thereafter.  This reduces the size of the code by about 2K bytes, in
 exchange for a little execution time.  However, BUILDFIXED should not be
 used for threaded applications, since the rewriting of the tables and virgin
 may not be thread-safe.
 */
let virgin = true

let lenfix, distfix // We have no pointers in JS, so keep tables separate

const fixedtables = state => {
  /* build fixed huffman tables if first call (may not be thread safe) */
  if (virgin) {
    lenfix = new Int32Array(512)
    distfix = new Int32Array(32)

    /* literal/length table */
    let sym = 0
    while (sym < 144) {
      state.lens[sym++] = 8
    }
    while (sym < 256) {
      state.lens[sym++] = 9
    }
    while (sym < 280) {
      state.lens[sym++] = 7
    }
    while (sym < 288) {
      state.lens[sym++] = 8
    }

    inflate_table(LENS, state.lens, 0, 288, lenfix, 0, state.work, { bits: 9 })

    /* distance table */
    sym = 0
    while (sym < 32) {
      state.lens[sym++] = 5
    }

    inflate_table(DISTS, state.lens, 0, 32, distfix, 0, state.work, { bits: 5 })

    /* do this just once */
    virgin = false
  }

  state.lencode = lenfix
  state.lenbits = 9
  state.distcode = distfix
  state.distbits = 5
}

/*
 Update the window with the last wsize (normally 32K) bytes written before
 returning.  If window does not exist yet, create it.  This is only called
 when a window is already in use, or when output has been written during this
 inflate call, but the end of the deflate stream has not been reached yet.
 It is also called to create a window for dictionary data when a dictionary
 is loaded.

 Providing output buffers larger than 32K to inflate() should provide a speed
 advantage, since only the last 32K of output is copied to the sliding window
 upon return from inflate(), and since all distances after the first 32K of
 output will fall in the output data, making match copies simpler and faster.
 The advantage may be dependent on the size of the processor's data caches.
 */
const updatewindow = (strm, src, end, copy) => {
  let dist
  const state = strm.state

  /* if it hasn't been done already, allocate space for the window */
  if (state.window === null) {
    state.wsize = 1 << state.wbits
    state.wnext = 0
    state.whave = 0

    state.window = new Uint8Array(state.wsize)
  }

  /* copy state->wsize or less output bytes into the circular window */
  if (copy >= state.wsize) {
    state.window.set(src.subarray(end - state.wsize, end), 0)
    state.wnext = 0
    state.whave = state.wsize
  } else {
    dist = state.wsize - state.wnext
    if (dist > copy) {
      dist = copy
    }
    //zmemcpy(state->window + state->wnext, end - copy, dist);
    state.window.set(src.subarray(end - copy, end - copy + dist), state.wnext)
    copy -= dist
    if (copy) {
      //zmemcpy(state->window, end - copy, copy);
      state.window.set(src.subarray(end - copy, end), 0)
      state.wnext = copy
      state.whave = state.wsize
    } else {
      state.wnext += dist
      if (state.wnext === state.wsize) {
        state.wnext = 0
      }
      if (state.whave < state.wsize) {
        state.whave += dist
      }
    }
  }
  return 0
}

const inflate = (strm, flush) => {
  let state
  let input, output // input/output buffers
  let next /* next input INDEX */
  let put /* next output INDEX */
  let have, left /* available input and output */
  let hold /* bit buffer */
  let bits /* bits in bit buffer */
  let _in, _out /* save starting available input and output */
  let copy /* number of stored or match bytes to copy */
  let from /* where to copy match bytes from */
  let from_source
  let here = 0 /* current decoding table entry */
  let here_bits, here_op, here_val // paked "here" denormalized (JS specific)
  //let last;                   /* parent table entry */
  let last_bits, last_op, last_val // paked "last" denormalized (JS specific)
  let len /* length to copy for repeats, bits to drop */
  let ret /* return code */
  const hbuf = new Uint8Array(4) /* buffer for gzip header crc calculation */
  let opts

  let n // temporary variable for NEED_BITS

  const order =
    /* permutation of code lengths */
    new Uint8Array([
      16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
    ])

  if (
    inflateStateCheck(strm) ||
    !strm.output ||
    (!strm.input && strm.avail_in !== 0)
  ) {
    return Z_STREAM_ERROR
  }

  state = strm.state
  if (state.mode === TYPE) {
    state.mode = TYPEDO
  } /* skip check */

  //--- LOAD() ---
  put = strm.next_out
  output = strm.output
  left = strm.avail_out
  next = strm.next_in
  input = strm.input
  have = strm.avail_in
  hold = state.hold
  bits = state.bits
  //---

  _in = have
  _out = left
  ret = Z_OK

  // goto emulation
  inf_leave: for (;;) {
    switch (state.mode) {
      case HEAD:
        if (state.wrap === 0) {
          state.mode = TYPEDO
          break
        }
        //=== NEEDBITS(16);
        while (bits < 16) {
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
        }
        //===//
        if (state.wrap & 2 && hold === 0x8b1f) {
          /* gzip header */
          if (state.wbits === 0) {
            state.wbits = 15
          }
          state.check = 0 /*crc32(0L, Z_NULL, 0)*/
          //=== CRC2(state.check, hold);
          hbuf[0] = hold & 0xff
          hbuf[1] = (hold >>> 8) & 0xff
          state.check = crc32(state.check, hbuf, 2, 0)
          //===//

          //=== INITBITS();
          hold = 0
          bits = 0
          //===//
          state.mode = FLAGS
          break
        }
        if (state.head) {
          state.head.done = false
        }
        if (
          !(state.wrap & 1) /* check if zlib header allowed */ ||
          (((hold & 0xff) /*BITS(8)*/ << 8) + (hold >> 8)) % 31
        ) {
          strm.msg = 'incorrect header check'
          state.mode = BAD
          break
        }
        if ((hold & 0x0f) /*BITS(4)*/ !== Z_DEFLATED) {
          strm.msg = 'unknown compression method'
          state.mode = BAD
          break
        }
        //--- DROPBITS(4) ---//
        hold >>>= 4
        bits -= 4
        //---//
        len = (hold & 0x0f) /*BITS(4)*/ + 8
        if (state.wbits === 0) {
          state.wbits = len
        }
        if (len > 15 || len > state.wbits) {
          strm.msg = 'invalid window size'
          state.mode = BAD
          break
        }

        // !!! pako patch. Force use `options.windowBits` if passed.
        // Required to always use max window size by default.
        state.dmax = 1 << state.wbits
        //state.dmax = 1 << len;

        state.flags = 0 /* indicate zlib header */
        //Tracev((stderr, "inflate:   zlib header ok\n"));
        strm.adler = state.check = 1 /*adler32(0L, Z_NULL, 0)*/
        state.mode = hold & 0x200 ? DICTID : TYPE
        //=== INITBITS();
        hold = 0
        bits = 0
        //===//
        break
      case FLAGS:
        //=== NEEDBITS(16); */
        while (bits < 16) {
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
        }
        //===//
        state.flags = hold
        if ((state.flags & 0xff) !== Z_DEFLATED) {
          strm.msg = 'unknown compression method'
          state.mode = BAD
          break
        }
        if (state.flags & 0xe000) {
          strm.msg = 'unknown header flags set'
          state.mode = BAD
          break
        }
        if (state.head) {
          state.head.text = (hold >> 8) & 1
        }
        if (state.flags & 0x0200 && state.wrap & 4) {
          //=== CRC2(state.check, hold);
          hbuf[0] = hold & 0xff
          hbuf[1] = (hold >>> 8) & 0xff
          state.check = crc32(state.check, hbuf, 2, 0)
          //===//
        }
        //=== INITBITS();
        hold = 0
        bits = 0
        //===//
        state.mode = TIME
      /* falls through */
      case TIME:
        //=== NEEDBITS(32); */
        while (bits < 32) {
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
        }
        //===//
        if (state.head) {
          state.head.time = hold
        }
        if (state.flags & 0x0200 && state.wrap & 4) {
          //=== CRC4(state.check, hold)
          hbuf[0] = hold & 0xff
          hbuf[1] = (hold >>> 8) & 0xff
          hbuf[2] = (hold >>> 16) & 0xff
          hbuf[3] = (hold >>> 24) & 0xff
          state.check = crc32(state.check, hbuf, 4, 0)
          //===
        }
        //=== INITBITS();
        hold = 0
        bits = 0
        //===//
        state.mode = OS
      /* falls through */
      case OS:
        //=== NEEDBITS(16); */
        while (bits < 16) {
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
        }
        //===//
        if (state.head) {
          state.head.xflags = hold & 0xff
          state.head.os = hold >> 8
        }
        if (state.flags & 0x0200 && state.wrap & 4) {
          //=== CRC2(state.check, hold);
          hbuf[0] = hold & 0xff
          hbuf[1] = (hold >>> 8) & 0xff
          state.check = crc32(state.check, hbuf, 2, 0)
          //===//
        }
        //=== INITBITS();
        hold = 0
        bits = 0
        //===//
        state.mode = EXLEN
      /* falls through */
      case EXLEN:
        if (state.flags & 0x0400) {
          //=== NEEDBITS(16); */
          while (bits < 16) {
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
          }
          //===//
          state.length = hold
          if (state.head) {
            state.head.extra_len = hold
          }
          if (state.flags & 0x0200 && state.wrap & 4) {
            //=== CRC2(state.check, hold);
            hbuf[0] = hold & 0xff
            hbuf[1] = (hold >>> 8) & 0xff
            state.check = crc32(state.check, hbuf, 2, 0)
            //===//
          }
          //=== INITBITS();
          hold = 0
          bits = 0
          //===//
        } else if (state.head) {
          state.head.extra = null /*Z_NULL*/
        }
        state.mode = EXTRA
      /* falls through */
      case EXTRA:
        if (state.flags & 0x0400) {
          copy = state.length
          if (copy > have) {
            copy = have
          }
          if (copy) {
            if (state.head) {
              len = state.head.extra_len - state.length
              if (!state.head.extra) {
                // Use untyped array for more convenient processing later
                state.head.extra = new Uint8Array(state.head.extra_len)
              }
              state.head.extra.set(
                input.subarray(
                  next,
                  // extra field is limited to 65536 bytes
                  // - no need for additional size check
                  next + copy
                ),
                /*len + copy > state.head.extra_max - len ? state.head.extra_max : copy,*/
                len
              )
              //zmemcpy(state.head.extra + len, next,
              //        len + copy > state.head.extra_max ?
              //        state.head.extra_max - len : copy);
            }
            if (state.flags & 0x0200 && state.wrap & 4) {
              state.check = crc32(state.check, input, copy, next)
            }
            have -= copy
            next += copy
            state.length -= copy
          }
          if (state.length) {
            break inf_leave
          }
        }
        state.length = 0
        state.mode = NAME
      /* falls through */
      case NAME:
        if (state.flags & 0x0800) {
          if (have === 0) {
            break inf_leave
          }
          copy = 0
          do {
            // TODO: 2 or 1 bytes?
            len = input[next + copy++]
            /* use constant limit because in js we should not preallocate memory */
            if (
              state.head &&
              len &&
              state.length < 65536 /*state.head.name_max*/
            ) {
              state.head.name += String.fromCharCode(len)
            }
          } while (len && copy < have)

          if (state.flags & 0x0200 && state.wrap & 4) {
            state.check = crc32(state.check, input, copy, next)
          }
          have -= copy
          next += copy
          if (len) {
            break inf_leave
          }
        } else if (state.head) {
          state.head.name = null
        }
        state.length = 0
        state.mode = COMMENT
      /* falls through */
      case COMMENT:
        if (state.flags & 0x1000) {
          if (have === 0) {
            break inf_leave
          }
          copy = 0
          do {
            len = input[next + copy++]
            /* use constant limit because in js we should not preallocate memory */
            if (
              state.head &&
              len &&
              state.length < 65536 /*state.head.comm_max*/
            ) {
              state.head.comment += String.fromCharCode(len)
            }
          } while (len && copy < have)
          if (state.flags & 0x0200 && state.wrap & 4) {
            state.check = crc32(state.check, input, copy, next)
          }
          have -= copy
          next += copy
          if (len) {
            break inf_leave
          }
        } else if (state.head) {
          state.head.comment = null
        }
        state.mode = HCRC
      /* falls through */
      case HCRC:
        if (state.flags & 0x0200) {
          //=== NEEDBITS(16); */
          while (bits < 16) {
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
          }
          //===//
          if (state.wrap & 4 && hold !== (state.check & 0xffff)) {
            strm.msg = 'header crc mismatch'
            state.mode = BAD
            break
          }
          //=== INITBITS();
          hold = 0
          bits = 0
          //===//
        }
        if (state.head) {
          state.head.hcrc = (state.flags >> 9) & 1
          state.head.done = true
        }
        strm.adler = state.check = 0
        state.mode = TYPE
        break
      case DICTID:
        //=== NEEDBITS(32); */
        while (bits < 32) {
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
        }
        //===//
        strm.adler = state.check = zswap32(hold)
        //=== INITBITS();
        hold = 0
        bits = 0
        //===//
        state.mode = DICT
      /* falls through */
      case DICT:
        if (state.havedict === 0) {
          //--- RESTORE() ---
          strm.next_out = put
          strm.avail_out = left
          strm.next_in = next
          strm.avail_in = have
          state.hold = hold
          state.bits = bits
          //---
          return Z_NEED_DICT
        }
        strm.adler = state.check = 1 /*adler32(0L, Z_NULL, 0)*/
        state.mode = TYPE
      /* falls through */
      case TYPE:
        if (flush === Z_BLOCK || flush === Z_TREES) {
          break inf_leave
        }
      /* falls through */
      case TYPEDO:
        if (state.last) {
          //--- BYTEBITS() ---//
          hold >>>= bits & 7
          bits -= bits & 7
          //---//
          state.mode = CHECK
          break
        }
        //=== NEEDBITS(3); */
        while (bits < 3) {
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
        }
        //===//
        state.last = hold & 0x01 /*BITS(1)*/
        //--- DROPBITS(1) ---//
        hold >>>= 1
        bits -= 1
        //---//

        switch (hold & 0x03 /*BITS(2)*/) {
          case 0 /* stored block */:
            //Tracev((stderr, "inflate:     stored block%s\n",
            //        state.last ? " (last)" : ""));
            state.mode = STORED
            break
          case 1 /* fixed block */:
            fixedtables(state)
            //Tracev((stderr, "inflate:     fixed codes block%s\n",
            //        state.last ? " (last)" : ""));
            state.mode = LEN_ /* decode codes */
            if (flush === Z_TREES) {
              //--- DROPBITS(2) ---//
              hold >>>= 2
              bits -= 2
              //---//
              break inf_leave
            }
            break
          case 2 /* dynamic block */:
            //Tracev((stderr, "inflate:     dynamic codes block%s\n",
            //        state.last ? " (last)" : ""));
            state.mode = TABLE
            break
          case 3:
            strm.msg = 'invalid block type'
            state.mode = BAD
        }
        //--- DROPBITS(2) ---//
        hold >>>= 2
        bits -= 2
        //---//
        break
      case STORED:
        //--- BYTEBITS() ---// /* go to byte boundary */
        hold >>>= bits & 7
        bits -= bits & 7
        //---//
        //=== NEEDBITS(32); */
        while (bits < 32) {
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
        }
        //===//
        if ((hold & 0xffff) !== ((hold >>> 16) ^ 0xffff)) {
          strm.msg = 'invalid stored block lengths'
          state.mode = BAD
          break
        }
        state.length = hold & 0xffff
        //Tracev((stderr, "inflate:       stored length %u\n",
        //        state.length));
        //=== INITBITS();
        hold = 0
        bits = 0
        //===//
        state.mode = COPY_
        if (flush === Z_TREES) {
          break inf_leave
        }
      /* falls through */
      case COPY_:
        state.mode = COPY
      /* falls through */
      case COPY:
        copy = state.length
        if (copy) {
          if (copy > have) {
            copy = have
          }
          if (copy > left) {
            copy = left
          }
          if (copy === 0) {
            break inf_leave
          }
          //--- zmemcpy(put, next, copy); ---
          output.set(input.subarray(next, next + copy), put)
          //---//
          have -= copy
          next += copy
          left -= copy
          put += copy
          state.length -= copy
          break
        }
        //Tracev((stderr, "inflate:       stored end\n"));
        state.mode = TYPE
        break
      case TABLE:
        //=== NEEDBITS(14); */
        while (bits < 14) {
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
        }
        //===//
        state.nlen = (hold & 0x1f) /*BITS(5)*/ + 257
        //--- DROPBITS(5) ---//
        hold >>>= 5
        bits -= 5
        //---//
        state.ndist = (hold & 0x1f) /*BITS(5)*/ + 1
        //--- DROPBITS(5) ---//
        hold >>>= 5
        bits -= 5
        //---//
        state.ncode = (hold & 0x0f) /*BITS(4)*/ + 4
        //--- DROPBITS(4) ---//
        hold >>>= 4
        bits -= 4
        //---//
        //#ifndef PKZIP_BUG_WORKAROUND
        if (state.nlen > 286 || state.ndist > 30) {
          strm.msg = 'too many length or distance symbols'
          state.mode = BAD
          break
        }
        //#endif
        //Tracev((stderr, "inflate:       table sizes ok\n"));
        state.have = 0
        state.mode = LENLENS
      /* falls through */
      case LENLENS:
        while (state.have < state.ncode) {
          //=== NEEDBITS(3);
          while (bits < 3) {
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
          }
          //===//
          state.lens[order[state.have++]] = hold & 0x07 //BITS(3);
          //--- DROPBITS(3) ---//
          hold >>>= 3
          bits -= 3
          //---//
        }
        while (state.have < 19) {
          state.lens[order[state.have++]] = 0
        }
        // We have separate tables & no pointers. 2 commented lines below not needed.
        //state.next = state.codes;
        //state.lencode = state.next;
        // Switch to use dynamic table
        state.lencode = state.lendyn
        state.lenbits = 7

        opts = { bits: state.lenbits }
        ret = inflate_table(
          CODES,
          state.lens,
          0,
          19,
          state.lencode,
          0,
          state.work,
          opts
        )
        state.lenbits = opts.bits

        if (ret) {
          strm.msg = 'invalid code lengths set'
          state.mode = BAD
          break
        }
        //Tracev((stderr, "inflate:       code lengths ok\n"));
        state.have = 0
        state.mode = CODELENS
      /* falls through */
      case CODELENS:
        while (state.have < state.nlen + state.ndist) {
          for (;;) {
            here =
              state.lencode[
                hold & ((1 << state.lenbits) - 1)
              ] /*BITS(state.lenbits)*/
            here_bits = here >>> 24
            here_op = (here >>> 16) & 0xff
            here_val = here & 0xffff

            if (here_bits <= bits) {
              break
            }
            //--- PULLBYTE() ---//
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
            //---//
          }
          if (here_val < 16) {
            //--- DROPBITS(here.bits) ---//
            hold >>>= here_bits
            bits -= here_bits
            //---//
            state.lens[state.have++] = here_val
          } else {
            if (here_val === 16) {
              //=== NEEDBITS(here.bits + 2);
              n = here_bits + 2
              while (bits < n) {
                if (have === 0) {
                  break inf_leave
                }
                have--
                hold += input[next++] << bits
                bits += 8
              }
              //===//
              //--- DROPBITS(here.bits) ---//
              hold >>>= here_bits
              bits -= here_bits
              //---//
              if (state.have === 0) {
                strm.msg = 'invalid bit length repeat'
                state.mode = BAD
                break
              }
              len = state.lens[state.have - 1]
              copy = 3 + (hold & 0x03) //BITS(2);
              //--- DROPBITS(2) ---//
              hold >>>= 2
              bits -= 2
              //---//
            } else if (here_val === 17) {
              //=== NEEDBITS(here.bits + 3);
              n = here_bits + 3
              while (bits < n) {
                if (have === 0) {
                  break inf_leave
                }
                have--
                hold += input[next++] << bits
                bits += 8
              }
              //===//
              //--- DROPBITS(here.bits) ---//
              hold >>>= here_bits
              bits -= here_bits
              //---//
              len = 0
              copy = 3 + (hold & 0x07) //BITS(3);
              //--- DROPBITS(3) ---//
              hold >>>= 3
              bits -= 3
              //---//
            } else {
              //=== NEEDBITS(here.bits + 7);
              n = here_bits + 7
              while (bits < n) {
                if (have === 0) {
                  break inf_leave
                }
                have--
                hold += input[next++] << bits
                bits += 8
              }
              //===//
              //--- DROPBITS(here.bits) ---//
              hold >>>= here_bits
              bits -= here_bits
              //---//
              len = 0
              copy = 11 + (hold & 0x7f) //BITS(7);
              //--- DROPBITS(7) ---//
              hold >>>= 7
              bits -= 7
              //---//
            }
            if (state.have + copy > state.nlen + state.ndist) {
              strm.msg = 'invalid bit length repeat'
              state.mode = BAD
              break
            }
            while (copy--) {
              state.lens[state.have++] = len
            }
          }
        }

        /* handle error breaks in while */
        if (state.mode === BAD) {
          break
        }

        /* check for end-of-block code (better have one) */
        if (state.lens[256] === 0) {
          strm.msg = 'invalid code -- missing end-of-block'
          state.mode = BAD
          break
        }

        /* build code tables -- note: do not change the lenbits or distbits
           values here (9 and 6) without reading the comments in inftrees.h
           concerning the ENOUGH constants, which depend on those values */
        state.lenbits = 9

        opts = { bits: state.lenbits }
        ret = inflate_table(
          LENS,
          state.lens,
          0,
          state.nlen,
          state.lencode,
          0,
          state.work,
          opts
        )
        // We have separate tables & no pointers. 2 commented lines below not needed.
        // state.next_index = opts.table_index;
        state.lenbits = opts.bits
        // state.lencode = state.next;

        if (ret) {
          strm.msg = 'invalid literal/lengths set'
          state.mode = BAD
          break
        }

        state.distbits = 6
        //state.distcode.copy(state.codes);
        // Switch to use dynamic table
        state.distcode = state.distdyn
        opts = { bits: state.distbits }
        ret = inflate_table(
          DISTS,
          state.lens,
          state.nlen,
          state.ndist,
          state.distcode,
          0,
          state.work,
          opts
        )
        // We have separate tables & no pointers. 2 commented lines below not needed.
        // state.next_index = opts.table_index;
        state.distbits = opts.bits
        // state.distcode = state.next;

        if (ret) {
          strm.msg = 'invalid distances set'
          state.mode = BAD
          break
        }
        //Tracev((stderr, 'inflate:       codes ok\n'));
        state.mode = LEN_
        if (flush === Z_TREES) {
          break inf_leave
        }
      /* falls through */
      case LEN_:
        state.mode = LEN
      /* falls through */
      case LEN:
        if (have >= 6 && left >= 258) {
          //--- RESTORE() ---
          strm.next_out = put
          strm.avail_out = left
          strm.next_in = next
          strm.avail_in = have
          state.hold = hold
          state.bits = bits
          //---
          inflate_fast(strm, _out)
          //--- LOAD() ---
          put = strm.next_out
          output = strm.output
          left = strm.avail_out
          next = strm.next_in
          input = strm.input
          have = strm.avail_in
          hold = state.hold
          bits = state.bits
          //---

          if (state.mode === TYPE) {
            state.back = -1
          }
          break
        }
        state.back = 0
        for (;;) {
          here =
            state.lencode[
              hold & ((1 << state.lenbits) - 1)
            ] /*BITS(state.lenbits)*/
          here_bits = here >>> 24
          here_op = (here >>> 16) & 0xff
          here_val = here & 0xffff

          if (here_bits <= bits) {
            break
          }
          //--- PULLBYTE() ---//
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
          //---//
        }
        if (here_op && (here_op & 0xf0) === 0) {
          last_bits = here_bits
          last_op = here_op
          last_val = here_val
          for (;;) {
            here =
              state.lencode[
                last_val +
                  ((hold &
                    ((1 << (last_bits + last_op)) -
                      1)) /*BITS(last.bits + last.op)*/ >>
                    last_bits)
              ]
            here_bits = here >>> 24
            here_op = (here >>> 16) & 0xff
            here_val = here & 0xffff

            if (last_bits + here_bits <= bits) {
              break
            }
            //--- PULLBYTE() ---//
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
            //---//
          }
          //--- DROPBITS(last.bits) ---//
          hold >>>= last_bits
          bits -= last_bits
          //---//
          state.back += last_bits
        }
        //--- DROPBITS(here.bits) ---//
        hold >>>= here_bits
        bits -= here_bits
        //---//
        state.back += here_bits
        state.length = here_val
        if (here_op === 0) {
          //Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
          //        "inflate:         literal '%c'\n" :
          //        "inflate:         literal 0x%02x\n", here.val));
          state.mode = LIT
          break
        }
        if (here_op & 32) {
          //Tracevv((stderr, "inflate:         end of block\n"));
          state.back = -1
          state.mode = TYPE
          break
        }
        if (here_op & 64) {
          strm.msg = 'invalid literal/length code'
          state.mode = BAD
          break
        }
        state.extra = here_op & 15
        state.mode = LENEXT
      /* falls through */
      case LENEXT:
        if (state.extra) {
          //=== NEEDBITS(state.extra);
          n = state.extra
          while (bits < n) {
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
          }
          //===//
          state.length += hold & ((1 << state.extra) - 1) /*BITS(state.extra)*/
          //--- DROPBITS(state.extra) ---//
          hold >>>= state.extra
          bits -= state.extra
          //---//
          state.back += state.extra
        }
        //Tracevv((stderr, "inflate:         length %u\n", state.length));
        state.was = state.length
        state.mode = DIST
      /* falls through */
      case DIST:
        for (;;) {
          here =
            state.distcode[
              hold & ((1 << state.distbits) - 1)
            ] /*BITS(state.distbits)*/
          here_bits = here >>> 24
          here_op = (here >>> 16) & 0xff
          here_val = here & 0xffff

          if (here_bits <= bits) {
            break
          }
          //--- PULLBYTE() ---//
          if (have === 0) {
            break inf_leave
          }
          have--
          hold += input[next++] << bits
          bits += 8
          //---//
        }
        if ((here_op & 0xf0) === 0) {
          last_bits = here_bits
          last_op = here_op
          last_val = here_val
          for (;;) {
            here =
              state.distcode[
                last_val +
                  ((hold &
                    ((1 << (last_bits + last_op)) -
                      1)) /*BITS(last.bits + last.op)*/ >>
                    last_bits)
              ]
            here_bits = here >>> 24
            here_op = (here >>> 16) & 0xff
            here_val = here & 0xffff

            if (last_bits + here_bits <= bits) {
              break
            }
            //--- PULLBYTE() ---//
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
            //---//
          }
          //--- DROPBITS(last.bits) ---//
          hold >>>= last_bits
          bits -= last_bits
          //---//
          state.back += last_bits
        }
        //--- DROPBITS(here.bits) ---//
        hold >>>= here_bits
        bits -= here_bits
        //---//
        state.back += here_bits
        if (here_op & 64) {
          strm.msg = 'invalid distance code'
          state.mode = BAD
          break
        }
        state.offset = here_val
        state.extra = here_op & 15
        state.mode = DISTEXT
      /* falls through */
      case DISTEXT:
        if (state.extra) {
          //=== NEEDBITS(state.extra);
          n = state.extra
          while (bits < n) {
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
          }
          //===//
          state.offset += hold & ((1 << state.extra) - 1) /*BITS(state.extra)*/
          //--- DROPBITS(state.extra) ---//
          hold >>>= state.extra
          bits -= state.extra
          //---//
          state.back += state.extra
        }
        //#ifdef INFLATE_STRICT
        if (state.offset > state.dmax) {
          strm.msg = 'invalid distance too far back'
          state.mode = BAD
          break
        }
        //#endif
        //Tracevv((stderr, "inflate:         distance %u\n", state.offset));
        state.mode = MATCH
      /* falls through */
      case MATCH:
        if (left === 0) {
          break inf_leave
        }
        copy = _out - left
        if (state.offset > copy) {
          /* copy from window */
          copy = state.offset - copy
          if (copy > state.whave) {
            if (state.sane) {
              strm.msg = 'invalid distance too far back'
              state.mode = BAD
              break
            }
            // (!) This block is disabled in zlib defaults,
            // don't enable it for binary compatibility
            //#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
            //          Trace((stderr, "inflate.c too far\n"));
            //          copy -= state.whave;
            //          if (copy > state.length) { copy = state.length; }
            //          if (copy > left) { copy = left; }
            //          left -= copy;
            //          state.length -= copy;
            //          do {
            //            output[put++] = 0;
            //          } while (--copy);
            //          if (state.length === 0) { state.mode = LEN; }
            //          break;
            //#endif
          }
          if (copy > state.wnext) {
            copy -= state.wnext
            from = state.wsize - copy
          } else {
            from = state.wnext - copy
          }
          if (copy > state.length) {
            copy = state.length
          }
          from_source = state.window
        } else {
          /* copy from output */
          from_source = output
          from = put - state.offset
          copy = state.length
        }
        if (copy > left) {
          copy = left
        }
        left -= copy
        state.length -= copy
        do {
          output[put++] = from_source[from++]
        } while (--copy)
        if (state.length === 0) {
          state.mode = LEN
        }
        break
      case LIT:
        if (left === 0) {
          break inf_leave
        }
        output[put++] = state.length
        left--
        state.mode = LEN
        break
      case CHECK:
        if (state.wrap) {
          //=== NEEDBITS(32);
          while (bits < 32) {
            if (have === 0) {
              break inf_leave
            }
            have--
            // Use '|' instead of '+' to make sure that result is signed
            hold |= input[next++] << bits
            bits += 8
          }
          //===//
          _out -= left
          strm.total_out += _out
          state.total += _out
          if (state.wrap & 4 && _out) {
            strm.adler = state.check =
              /*UPDATE_CHECK(state.check, put - _out, _out);*/
              state.flags
                ? crc32(state.check, output, _out, put - _out)
                : adler32(state.check, output, _out, put - _out)
          }
          _out = left
          // NB: crc32 stored as signed 32-bit int, zswap32 returns signed too
          if (
            state.wrap & 4 &&
            (state.flags ? hold : zswap32(hold)) !== state.check
          ) {
            strm.msg = 'incorrect data check'
            state.mode = BAD
            break
          }
          //=== INITBITS();
          hold = 0
          bits = 0
          //===//
          //Tracev((stderr, "inflate:   check matches trailer\n"));
        }
        state.mode = LENGTH
      /* falls through */
      case LENGTH:
        if (state.wrap && state.flags) {
          //=== NEEDBITS(32);
          while (bits < 32) {
            if (have === 0) {
              break inf_leave
            }
            have--
            hold += input[next++] << bits
            bits += 8
          }
          //===//
          if (state.wrap & 4 && hold !== (state.total & 0xffffffff)) {
            strm.msg = 'incorrect length check'
            state.mode = BAD
            break
          }
          //=== INITBITS();
          hold = 0
          bits = 0
          //===//
          //Tracev((stderr, "inflate:   length matches trailer\n"));
        }
        state.mode = DONE
      /* falls through */
      case DONE:
        ret = Z_STREAM_END
        break inf_leave
      case BAD:
        ret = Z_DATA_ERROR
        break inf_leave
      case MEM:
        return Z_MEM_ERROR
      case SYNC:
      /* falls through */
      default:
        return Z_STREAM_ERROR
    }
  }

  // inf_leave <- here is real place for "goto inf_leave", emulated via "break inf_leave"

  /*
     Return from inflate(), updating the total counts and the check value.
     If there was no progress during the inflate() call, return a buffer
     error.  Call updatewindow() to create and/or update the window state.
     Note: a memory error from inflate() is non-recoverable.
   */

  //--- RESTORE() ---
  strm.next_out = put
  strm.avail_out = left
  strm.next_in = next
  strm.avail_in = have
  state.hold = hold
  state.bits = bits
  //---

  if (
    state.wsize ||
    (_out !== strm.avail_out &&
      state.mode < BAD &&
      (state.mode < CHECK || flush !== Z_FINISH))
  ) {
    if (updatewindow(strm, strm.output, strm.next_out, _out - strm.avail_out)) {
      state.mode = MEM
      return Z_MEM_ERROR
    }
  }
  _in -= strm.avail_in
  _out -= strm.avail_out
  strm.total_in += _in
  strm.total_out += _out
  state.total += _out
  if (state.wrap & 4 && _out) {
    strm.adler = state.check =
      /*UPDATE_CHECK(state.check, strm.next_out - _out, _out);*/
      state.flags
        ? crc32(state.check, output, _out, strm.next_out - _out)
        : adler32(state.check, output, _out, strm.next_out - _out)
  }
  strm.data_type =
    state.bits +
    (state.last ? 64 : 0) +
    (state.mode === TYPE ? 128 : 0) +
    (state.mode === LEN_ || state.mode === COPY_ ? 256 : 0)
  if (((_in === 0 && _out === 0) || flush === Z_FINISH) && ret === Z_OK) {
    ret = Z_BUF_ERROR
  }
  return ret
}

const inflateEnd = strm => {
  if (inflateStateCheck(strm)) {
    return Z_STREAM_ERROR
  }

  let state = strm.state
  if (state.window) {
    state.window = null
  }
  strm.state = null
  return Z_OK
}

const inflateGetHeader = (strm, head) => {
  /* check state */
  if (inflateStateCheck(strm)) {
    return Z_STREAM_ERROR
  }
  const state = strm.state
  if ((state.wrap & 2) === 0) {
    return Z_STREAM_ERROR
  }

  /* save header structure */
  state.head = head
  head.done = false
  return Z_OK
}

const inflateSetDictionary = (strm, dictionary) => {
  const dictLength = dictionary.length

  let state
  let dictid
  let ret

  /* check state */
  if (inflateStateCheck(strm)) {
    return Z_STREAM_ERROR
  }
  state = strm.state

  if (state.wrap !== 0 && state.mode !== DICT) {
    return Z_STREAM_ERROR
  }

  /* check for correct dictionary identifier */
  if (state.mode === DICT) {
    dictid = 1 /* adler32(0, null, 0)*/
    /* dictid = adler32(dictid, dictionary, dictLength); */
    dictid = adler32(dictid, dictionary, dictLength, 0)
    if (dictid !== state.check) {
      return Z_DATA_ERROR
    }
  }
  /* copy dictionary to window using updatewindow(), which will amend the
   existing dictionary if appropriate */
  ret = updatewindow(strm, dictionary, dictLength, dictLength)
  if (ret) {
    state.mode = MEM
    return Z_MEM_ERROR
  }
  state.havedict = 1
  // Tracev((stderr, "inflate:   dictionary set\n"));
  return Z_OK
}

export default {
  inflateReset,
  inflateInit,
  inflateInit2,
  inflate,
  inflateEnd,
  inflateGetHeader,
  inflateSetDictionary
}