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fflate.module.js
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fflate.module.js
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/*!
fflate - fast JavaScript compression/decompression
<https://101arrowz.github.io/fflate>
Licensed under MIT. https://github.com/101arrowz/fflate/blob/master/LICENSE
version 0.6.9
*/
// DEFLATE is a complex format; to read this code, you should probably check the RFC first:
// https://tools.ietf.org/html/rfc1951
// You may also wish to take a look at the guide I made about this program:
// https://gist.github.com/101arrowz/253f31eb5abc3d9275ab943003ffecad
// Some of the following code is similar to that of UZIP.js:
// https://github.com/photopea/UZIP.js
// However, the vast majority of the codebase has diverged from UZIP.js to increase performance and reduce bundle size.
// Sometimes 0 will appear where -1 would be more appropriate. This is because using a uint
// is better for memory in most engines (I *think*).
var ch2 = {};
var durl = function (c) { return URL.createObjectURL(new Blob([c], { type: 'text/javascript' })); };
var cwk = function (u) { return new Worker(u); };
try {
URL.revokeObjectURL(durl(''));
}
catch (e) {
// We're in Deno or a very old browser
durl = function (c) { return 'data:application/javascript;charset=UTF-8,' + encodeURI(c); };
// If Deno, this is necessary; if not, this changes nothing
cwk = function (u) { return new Worker(u, { type: 'module' }); };
}
var wk = (function (c, id, msg, transfer, cb) {
var w = cwk(ch2[id] || (ch2[id] = durl(c)));
w.onerror = function (e) { return cb(e.error, null); };
w.onmessage = function (e) { return cb(null, e.data); };
w.postMessage(msg, transfer);
return w;
});
// aliases for shorter compressed code (most minifers don't do this)
var u8 = Uint8Array, u16 = Uint16Array, u32 = Uint32Array;
// fixed length extra bits
var fleb = new u8([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, /* unused */ 0, 0, /* impossible */ 0]);
// fixed distance extra bits
// see fleb note
var fdeb = new u8([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, /* unused */ 0, 0]);
// code length index map
var clim = new u8([16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15]);
// get base, reverse index map from extra bits
var freb = function (eb, start) {
var b = new u16(31);
for (var i = 0; i < 31; ++i) {
b[i] = start += 1 << eb[i - 1];
}
// numbers here are at max 18 bits
var r = new u32(b[30]);
for (var i = 1; i < 30; ++i) {
for (var j = b[i]; j < b[i + 1]; ++j) {
r[j] = ((j - b[i]) << 5) | i;
}
}
return [b, r];
};
var _a = freb(fleb, 2), fl = _a[0], revfl = _a[1];
// we can ignore the fact that the other numbers are wrong; they never happen anyway
fl[28] = 258, revfl[258] = 28;
var _b = freb(fdeb, 0), fd = _b[0], revfd = _b[1];
// map of value to reverse (assuming 16 bits)
var rev = new u16(32768);
for (var i = 0; i < 32768; ++i) {
// reverse table algorithm from SO
var x = ((i & 0xAAAA) >>> 1) | ((i & 0x5555) << 1);
x = ((x & 0xCCCC) >>> 2) | ((x & 0x3333) << 2);
x = ((x & 0xF0F0) >>> 4) | ((x & 0x0F0F) << 4);
rev[i] = (((x & 0xFF00) >>> 8) | ((x & 0x00FF) << 8)) >>> 1;
}
// create huffman tree from u8 "map": index -> code length for code index
// mb (max bits) must be at most 15
// TODO: optimize/split up?
var hMap = (function (cd, mb, r) {
var s = cd.length;
// index
var i = 0;
// u16 "map": index -> # of codes with bit length = index
var l = new u16(mb);
// length of cd must be 288 (total # of codes)
for (; i < s; ++i)
++l[cd[i] - 1];
// u16 "map": index -> minimum code for bit length = index
var le = new u16(mb);
for (i = 0; i < mb; ++i) {
le[i] = (le[i - 1] + l[i - 1]) << 1;
}
var co;
if (r) {
// u16 "map": index -> number of actual bits, symbol for code
co = new u16(1 << mb);
// bits to remove for reverser
var rvb = 15 - mb;
for (i = 0; i < s; ++i) {
// ignore 0 lengths
if (cd[i]) {
// num encoding both symbol and bits read
var sv = (i << 4) | cd[i];
// free bits
var r_1 = mb - cd[i];
// start value
var v = le[cd[i] - 1]++ << r_1;
// m is end value
for (var m = v | ((1 << r_1) - 1); v <= m; ++v) {
// every 16 bit value starting with the code yields the same result
co[rev[v] >>> rvb] = sv;
}
}
}
}
else {
co = new u16(s);
for (i = 0; i < s; ++i) {
if (cd[i]) {
co[i] = rev[le[cd[i] - 1]++] >>> (15 - cd[i]);
}
}
}
return co;
});
// fixed length tree
var flt = new u8(288);
for (var i = 0; i < 144; ++i)
flt[i] = 8;
for (var i = 144; i < 256; ++i)
flt[i] = 9;
for (var i = 256; i < 280; ++i)
flt[i] = 7;
for (var i = 280; i < 288; ++i)
flt[i] = 8;
// fixed distance tree
var fdt = new u8(32);
for (var i = 0; i < 32; ++i)
fdt[i] = 5;
// fixed length map
var flm = /*#__PURE__*/ hMap(flt, 9, 0), flrm = /*#__PURE__*/ hMap(flt, 9, 1);
// fixed distance map
var fdm = /*#__PURE__*/ hMap(fdt, 5, 0), fdrm = /*#__PURE__*/ hMap(fdt, 5, 1);
// find max of array
var max = function (a) {
var m = a[0];
for (var i = 1; i < a.length; ++i) {
if (a[i] > m)
m = a[i];
}
return m;
};
// read d, starting at bit p and mask with m
var bits = function (d, p, m) {
var o = (p / 8) | 0;
return ((d[o] | (d[o + 1] << 8)) >> (p & 7)) & m;
};
// read d, starting at bit p continuing for at least 16 bits
var bits16 = function (d, p) {
var o = (p / 8) | 0;
return ((d[o] | (d[o + 1] << 8) | (d[o + 2] << 16)) >> (p & 7));
};
// get end of byte
var shft = function (p) { return ((p / 8) | 0) + (p & 7 && 1); };
// typed array slice - allows garbage collector to free original reference,
// while being more compatible than .slice
var slc = function (v, s, e) {
if (s == null || s < 0)
s = 0;
if (e == null || e > v.length)
e = v.length;
// can't use .constructor in case user-supplied
var n = new (v instanceof u16 ? u16 : v instanceof u32 ? u32 : u8)(e - s);
n.set(v.subarray(s, e));
return n;
};
// expands raw DEFLATE data
var inflt = function (dat, buf, st) {
// source length
var sl = dat.length;
if (!sl || (st && !st.l && sl < 5))
return buf || new u8(0);
// have to estimate size
var noBuf = !buf || st;
// no state
var noSt = !st || st.i;
if (!st)
st = {};
// Assumes roughly 33% compression ratio average
if (!buf)
buf = new u8(sl * 3);
// ensure buffer can fit at least l elements
var cbuf = function (l) {
var bl = buf.length;
// need to increase size to fit
if (l > bl) {
// Double or set to necessary, whichever is greater
var nbuf = new u8(Math.max(bl * 2, l));
nbuf.set(buf);
buf = nbuf;
}
};
// last chunk bitpos bytes
var final = st.f || 0, pos = st.p || 0, bt = st.b || 0, lm = st.l, dm = st.d, lbt = st.m, dbt = st.n;
// total bits
var tbts = sl * 8;
do {
if (!lm) {
// BFINAL - this is only 1 when last chunk is next
st.f = final = bits(dat, pos, 1);
// type: 0 = no compression, 1 = fixed huffman, 2 = dynamic huffman
var type = bits(dat, pos + 1, 3);
pos += 3;
if (!type) {
// go to end of byte boundary
var s = shft(pos) + 4, l = dat[s - 4] | (dat[s - 3] << 8), t = s + l;
if (t > sl) {
if (noSt)
throw 'unexpected EOF';
break;
}
// ensure size
if (noBuf)
cbuf(bt + l);
// Copy over uncompressed data
buf.set(dat.subarray(s, t), bt);
// Get new bitpos, update byte count
st.b = bt += l, st.p = pos = t * 8;
continue;
}
else if (type == 1)
lm = flrm, dm = fdrm, lbt = 9, dbt = 5;
else if (type == 2) {
// literal lengths
var hLit = bits(dat, pos, 31) + 257, hcLen = bits(dat, pos + 10, 15) + 4;
var tl = hLit + bits(dat, pos + 5, 31) + 1;
pos += 14;
// length+distance tree
var ldt = new u8(tl);
// code length tree
var clt = new u8(19);
for (var i = 0; i < hcLen; ++i) {
// use index map to get real code
clt[clim[i]] = bits(dat, pos + i * 3, 7);
}
pos += hcLen * 3;
// code lengths bits
var clb = max(clt), clbmsk = (1 << clb) - 1;
// code lengths map
var clm = hMap(clt, clb, 1);
for (var i = 0; i < tl;) {
var r = clm[bits(dat, pos, clbmsk)];
// bits read
pos += r & 15;
// symbol
var s = r >>> 4;
// code length to copy
if (s < 16) {
ldt[i++] = s;
}
else {
// copy count
var c = 0, n = 0;
if (s == 16)
n = 3 + bits(dat, pos, 3), pos += 2, c = ldt[i - 1];
else if (s == 17)
n = 3 + bits(dat, pos, 7), pos += 3;
else if (s == 18)
n = 11 + bits(dat, pos, 127), pos += 7;
while (n--)
ldt[i++] = c;
}
}
// length tree distance tree
var lt = ldt.subarray(0, hLit), dt = ldt.subarray(hLit);
// max length bits
lbt = max(lt);
// max dist bits
dbt = max(dt);
lm = hMap(lt, lbt, 1);
dm = hMap(dt, dbt, 1);
}
else
throw 'invalid block type';
if (pos > tbts) {
if (noSt)
throw 'unexpected EOF';
break;
}
}
// Make sure the buffer can hold this + the largest possible addition
// Maximum chunk size (practically, theoretically infinite) is 2^17;
if (noBuf)
cbuf(bt + 131072);
var lms = (1 << lbt) - 1, dms = (1 << dbt) - 1;
var lpos = pos;
for (;; lpos = pos) {
// bits read, code
var c = lm[bits16(dat, pos) & lms], sym = c >>> 4;
pos += c & 15;
if (pos > tbts) {
if (noSt)
throw 'unexpected EOF';
break;
}
if (!c)
throw 'invalid length/literal';
if (sym < 256)
buf[bt++] = sym;
else if (sym == 256) {
lpos = pos, lm = null;
break;
}
else {
var add = sym - 254;
// no extra bits needed if less
if (sym > 264) {
// index
var i = sym - 257, b = fleb[i];
add = bits(dat, pos, (1 << b) - 1) + fl[i];
pos += b;
}
// dist
var d = dm[bits16(dat, pos) & dms], dsym = d >>> 4;
if (!d)
throw 'invalid distance';
pos += d & 15;
var dt = fd[dsym];
if (dsym > 3) {
var b = fdeb[dsym];
dt += bits16(dat, pos) & ((1 << b) - 1), pos += b;
}
if (pos > tbts) {
if (noSt)
throw 'unexpected EOF';
break;
}
if (noBuf)
cbuf(bt + 131072);
var end = bt + add;
for (; bt < end; bt += 4) {
buf[bt] = buf[bt - dt];
buf[bt + 1] = buf[bt + 1 - dt];
buf[bt + 2] = buf[bt + 2 - dt];
buf[bt + 3] = buf[bt + 3 - dt];
}
bt = end;
}
}
st.l = lm, st.p = lpos, st.b = bt;
if (lm)
final = 1, st.m = lbt, st.d = dm, st.n = dbt;
} while (!final);
return bt == buf.length ? buf : slc(buf, 0, bt);
};
// starting at p, write the minimum number of bits that can hold v to d
var wbits = function (d, p, v) {
v <<= p & 7;
var o = (p / 8) | 0;
d[o] |= v;
d[o + 1] |= v >>> 8;
};
// starting at p, write the minimum number of bits (>8) that can hold v to d
var wbits16 = function (d, p, v) {
v <<= p & 7;
var o = (p / 8) | 0;
d[o] |= v;
d[o + 1] |= v >>> 8;
d[o + 2] |= v >>> 16;
};
// creates code lengths from a frequency table
var hTree = function (d, mb) {
// Need extra info to make a tree
var t = [];
for (var i = 0; i < d.length; ++i) {
if (d[i])
t.push({ s: i, f: d[i] });
}
var s = t.length;
var t2 = t.slice();
if (!s)
return [et, 0];
if (s == 1) {
var v = new u8(t[0].s + 1);
v[t[0].s] = 1;
return [v, 1];
}
t.sort(function (a, b) { return a.f - b.f; });
// after i2 reaches last ind, will be stopped
// freq must be greater than largest possible number of symbols
t.push({ s: -1, f: 25001 });
var l = t[0], r = t[1], i0 = 0, i1 = 1, i2 = 2;
t[0] = { s: -1, f: l.f + r.f, l: l, r: r };
// efficient algorithm from UZIP.js
// i0 is lookbehind, i2 is lookahead - after processing two low-freq
// symbols that combined have high freq, will start processing i2 (high-freq,
// non-composite) symbols instead
// see https://reddit.com/r/photopea/comments/ikekht/uzipjs_questions/
while (i1 != s - 1) {
l = t[t[i0].f < t[i2].f ? i0++ : i2++];
r = t[i0 != i1 && t[i0].f < t[i2].f ? i0++ : i2++];
t[i1++] = { s: -1, f: l.f + r.f, l: l, r: r };
}
var maxSym = t2[0].s;
for (var i = 1; i < s; ++i) {
if (t2[i].s > maxSym)
maxSym = t2[i].s;
}
// code lengths
var tr = new u16(maxSym + 1);
// max bits in tree
var mbt = ln(t[i1 - 1], tr, 0);
if (mbt > mb) {
// more algorithms from UZIP.js
// TODO: find out how this code works (debt)
// ind debt
var i = 0, dt = 0;
// left cost
var lft = mbt - mb, cst = 1 << lft;
t2.sort(function (a, b) { return tr[b.s] - tr[a.s] || a.f - b.f; });
for (; i < s; ++i) {
var i2_1 = t2[i].s;
if (tr[i2_1] > mb) {
dt += cst - (1 << (mbt - tr[i2_1]));
tr[i2_1] = mb;
}
else
break;
}
dt >>>= lft;
while (dt > 0) {
var i2_2 = t2[i].s;
if (tr[i2_2] < mb)
dt -= 1 << (mb - tr[i2_2]++ - 1);
else
++i;
}
for (; i >= 0 && dt; --i) {
var i2_3 = t2[i].s;
if (tr[i2_3] == mb) {
--tr[i2_3];
++dt;
}
}
mbt = mb;
}
return [new u8(tr), mbt];
};
// get the max length and assign length codes
var ln = function (n, l, d) {
return n.s == -1
? Math.max(ln(n.l, l, d + 1), ln(n.r, l, d + 1))
: (l[n.s] = d);
};
// length codes generation
var lc = function (c) {
var s = c.length;
// Note that the semicolon was intentional
while (s && !c[--s])
;
var cl = new u16(++s);
// ind num streak
var cli = 0, cln = c[0], cls = 1;
var w = function (v) { cl[cli++] = v; };
for (var i = 1; i <= s; ++i) {
if (c[i] == cln && i != s)
++cls;
else {
if (!cln && cls > 2) {
for (; cls > 138; cls -= 138)
w(32754);
if (cls > 2) {
w(cls > 10 ? ((cls - 11) << 5) | 28690 : ((cls - 3) << 5) | 12305);
cls = 0;
}
}
else if (cls > 3) {
w(cln), --cls;
for (; cls > 6; cls -= 6)
w(8304);
if (cls > 2)
w(((cls - 3) << 5) | 8208), cls = 0;
}
while (cls--)
w(cln);
cls = 1;
cln = c[i];
}
}
return [cl.subarray(0, cli), s];
};
// calculate the length of output from tree, code lengths
var clen = function (cf, cl) {
var l = 0;
for (var i = 0; i < cl.length; ++i)
l += cf[i] * cl[i];
return l;
};
// writes a fixed block
// returns the new bit pos
var wfblk = function (out, pos, dat) {
// no need to write 00 as type: TypedArray defaults to 0
var s = dat.length;
var o = shft(pos + 2);
out[o] = s & 255;
out[o + 1] = s >>> 8;
out[o + 2] = out[o] ^ 255;
out[o + 3] = out[o + 1] ^ 255;
for (var i = 0; i < s; ++i)
out[o + i + 4] = dat[i];
return (o + 4 + s) * 8;
};
// writes a block
var wblk = function (dat, out, final, syms, lf, df, eb, li, bs, bl, p) {
wbits(out, p++, final);
++lf[256];
var _a = hTree(lf, 15), dlt = _a[0], mlb = _a[1];
var _b = hTree(df, 15), ddt = _b[0], mdb = _b[1];
var _c = lc(dlt), lclt = _c[0], nlc = _c[1];
var _d = lc(ddt), lcdt = _d[0], ndc = _d[1];
var lcfreq = new u16(19);
for (var i = 0; i < lclt.length; ++i)
lcfreq[lclt[i] & 31]++;
for (var i = 0; i < lcdt.length; ++i)
lcfreq[lcdt[i] & 31]++;
var _e = hTree(lcfreq, 7), lct = _e[0], mlcb = _e[1];
var nlcc = 19;
for (; nlcc > 4 && !lct[clim[nlcc - 1]]; --nlcc)
;
var flen = (bl + 5) << 3;
var ftlen = clen(lf, flt) + clen(df, fdt) + eb;
var dtlen = clen(lf, dlt) + clen(df, ddt) + eb + 14 + 3 * nlcc + clen(lcfreq, lct) + (2 * lcfreq[16] + 3 * lcfreq[17] + 7 * lcfreq[18]);
if (flen <= ftlen && flen <= dtlen)
return wfblk(out, p, dat.subarray(bs, bs + bl));
var lm, ll, dm, dl;
wbits(out, p, 1 + (dtlen < ftlen)), p += 2;
if (dtlen < ftlen) {
lm = hMap(dlt, mlb, 0), ll = dlt, dm = hMap(ddt, mdb, 0), dl = ddt;
var llm = hMap(lct, mlcb, 0);
wbits(out, p, nlc - 257);
wbits(out, p + 5, ndc - 1);
wbits(out, p + 10, nlcc - 4);
p += 14;
for (var i = 0; i < nlcc; ++i)
wbits(out, p + 3 * i, lct[clim[i]]);
p += 3 * nlcc;
var lcts = [lclt, lcdt];
for (var it = 0; it < 2; ++it) {
var clct = lcts[it];
for (var i = 0; i < clct.length; ++i) {
var len = clct[i] & 31;
wbits(out, p, llm[len]), p += lct[len];
if (len > 15)
wbits(out, p, (clct[i] >>> 5) & 127), p += clct[i] >>> 12;
}
}
}
else {
lm = flm, ll = flt, dm = fdm, dl = fdt;
}
for (var i = 0; i < li; ++i) {
if (syms[i] > 255) {
var len = (syms[i] >>> 18) & 31;
wbits16(out, p, lm[len + 257]), p += ll[len + 257];
if (len > 7)
wbits(out, p, (syms[i] >>> 23) & 31), p += fleb[len];
var dst = syms[i] & 31;
wbits16(out, p, dm[dst]), p += dl[dst];
if (dst > 3)
wbits16(out, p, (syms[i] >>> 5) & 8191), p += fdeb[dst];
}
else {
wbits16(out, p, lm[syms[i]]), p += ll[syms[i]];
}
}
wbits16(out, p, lm[256]);
return p + ll[256];
};
// deflate options (nice << 13) | chain
var deo = /*#__PURE__*/ new u32([65540, 131080, 131088, 131104, 262176, 1048704, 1048832, 2114560, 2117632]);
// empty
var et = /*#__PURE__*/ new u8(0);
// compresses data into a raw DEFLATE buffer
var dflt = function (dat, lvl, plvl, pre, post, lst) {
var s = dat.length;
var o = new u8(pre + s + 5 * (1 + Math.ceil(s / 7000)) + post);
// writing to this writes to the output buffer
var w = o.subarray(pre, o.length - post);
var pos = 0;
if (!lvl || s < 8) {
for (var i = 0; i <= s; i += 65535) {
// end
var e = i + 65535;
if (e < s) {
// write full block
pos = wfblk(w, pos, dat.subarray(i, e));
}
else {
// write final block
w[i] = lst;
pos = wfblk(w, pos, dat.subarray(i, s));
}
}
}
else {
var opt = deo[lvl - 1];
var n = opt >>> 13, c = opt & 8191;
var msk_1 = (1 << plvl) - 1;
// prev 2-byte val map curr 2-byte val map
var prev = new u16(32768), head = new u16(msk_1 + 1);
var bs1_1 = Math.ceil(plvl / 3), bs2_1 = 2 * bs1_1;
var hsh = function (i) { return (dat[i] ^ (dat[i + 1] << bs1_1) ^ (dat[i + 2] << bs2_1)) & msk_1; };
// 24576 is an arbitrary number of maximum symbols per block
// 424 buffer for last block
var syms = new u32(25000);
// length/literal freq distance freq
var lf = new u16(288), df = new u16(32);
// l/lcnt exbits index l/lind waitdx bitpos
var lc_1 = 0, eb = 0, i = 0, li = 0, wi = 0, bs = 0;
for (; i < s; ++i) {
// hash value
// deopt when i > s - 3 - at end, deopt acceptable
var hv = hsh(i);
// index mod 32768 previous index mod
var imod = i & 32767, pimod = head[hv];
prev[imod] = pimod;
head[hv] = imod;
// We always should modify head and prev, but only add symbols if
// this data is not yet processed ("wait" for wait index)
if (wi <= i) {
// bytes remaining
var rem = s - i;
if ((lc_1 > 7000 || li > 24576) && rem > 423) {
pos = wblk(dat, w, 0, syms, lf, df, eb, li, bs, i - bs, pos);
li = lc_1 = eb = 0, bs = i;
for (var j = 0; j < 286; ++j)
lf[j] = 0;
for (var j = 0; j < 30; ++j)
df[j] = 0;
}
// len dist chain
var l = 2, d = 0, ch_1 = c, dif = (imod - pimod) & 32767;
if (rem > 2 && hv == hsh(i - dif)) {
var maxn = Math.min(n, rem) - 1;
var maxd = Math.min(32767, i);
// max possible length
// not capped at dif because decompressors implement "rolling" index population
var ml = Math.min(258, rem);
while (dif <= maxd && --ch_1 && imod != pimod) {
if (dat[i + l] == dat[i + l - dif]) {
var nl = 0;
for (; nl < ml && dat[i + nl] == dat[i + nl - dif]; ++nl)
;
if (nl > l) {
l = nl, d = dif;
// break out early when we reach "nice" (we are satisfied enough)
if (nl > maxn)
break;
// now, find the rarest 2-byte sequence within this
// length of literals and search for that instead.
// Much faster than just using the start
var mmd = Math.min(dif, nl - 2);
var md = 0;
for (var j = 0; j < mmd; ++j) {
var ti = (i - dif + j + 32768) & 32767;
var pti = prev[ti];
var cd = (ti - pti + 32768) & 32767;
if (cd > md)
md = cd, pimod = ti;
}
}
}
// check the previous match
imod = pimod, pimod = prev[imod];
dif += (imod - pimod + 32768) & 32767;
}
}
// d will be nonzero only when a match was found
if (d) {
// store both dist and len data in one Uint32
// Make sure this is recognized as a len/dist with 28th bit (2^28)
syms[li++] = 268435456 | (revfl[l] << 18) | revfd[d];
var lin = revfl[l] & 31, din = revfd[d] & 31;
eb += fleb[lin] + fdeb[din];
++lf[257 + lin];
++df[din];
wi = i + l;
++lc_1;
}
else {
syms[li++] = dat[i];
++lf[dat[i]];
}
}
}
pos = wblk(dat, w, lst, syms, lf, df, eb, li, bs, i - bs, pos);
// this is the easiest way to avoid needing to maintain state
if (!lst && pos & 7)
pos = wfblk(w, pos + 1, et);
}
return slc(o, 0, pre + shft(pos) + post);
};
// CRC32 table
var crct = /*#__PURE__*/ (function () {
var t = new u32(256);
for (var i = 0; i < 256; ++i) {
var c = i, k = 9;
while (--k)
c = ((c & 1) && 0xEDB88320) ^ (c >>> 1);
t[i] = c;
}
return t;
})();
// CRC32
var crc = function () {
var c = -1;
return {
p: function (d) {
// closures have awful performance
var cr = c;
for (var i = 0; i < d.length; ++i)
cr = crct[(cr & 255) ^ d[i]] ^ (cr >>> 8);
c = cr;
},
d: function () { return ~c; }
};
};
// Alder32
var adler = function () {
var a = 1, b = 0;
return {
p: function (d) {
// closures have awful performance
var n = a, m = b;
var l = d.length;
for (var i = 0; i != l;) {
var e = Math.min(i + 2655, l);
for (; i < e; ++i)
m += n += d[i];
n = (n & 65535) + 15 * (n >> 16), m = (m & 65535) + 15 * (m >> 16);
}
a = n, b = m;
},
d: function () {
a %= 65521, b %= 65521;
return (a & 255) << 24 | (a >>> 8) << 16 | (b & 255) << 8 | (b >>> 8);
}
};
};
;
// deflate with opts
var dopt = function (dat, opt, pre, post, st) {
return dflt(dat, opt.level == null ? 6 : opt.level, opt.mem == null ? Math.ceil(Math.max(8, Math.min(13, Math.log(dat.length))) * 1.5) : (12 + opt.mem), pre, post, !st);
};
// Walmart object spread
var mrg = function (a, b) {
var o = {};
for (var k in a)
o[k] = a[k];
for (var k in b)
o[k] = b[k];
return o;
};
// worker clone
// This is possibly the craziest part of the entire codebase, despite how simple it may seem.
// The only parameter to this function is a closure that returns an array of variables outside of the function scope.
// We're going to try to figure out the variable names used in the closure as strings because that is crucial for workerization.
// We will return an object mapping of true variable name to value (basically, the current scope as a JS object).
// The reason we can't just use the original variable names is minifiers mangling the toplevel scope.
// This took me three weeks to figure out how to do.
var wcln = function (fn, fnStr, td) {
var dt = fn();
var st = fn.toString();
var ks = st.slice(st.indexOf('[') + 1, st.lastIndexOf(']')).replace(/ /g, '').split(',');
for (var i = 0; i < dt.length; ++i) {
var v = dt[i], k = ks[i];
if (typeof v == 'function') {
fnStr += ';' + k + '=';
var st_1 = v.toString();
if (v.prototype) {
// for global objects
if (st_1.indexOf('[native code]') != -1) {
var spInd = st_1.indexOf(' ', 8) + 1;
fnStr += st_1.slice(spInd, st_1.indexOf('(', spInd));
}
else {
fnStr += st_1;
for (var t in v.prototype)
fnStr += ';' + k + '.prototype.' + t + '=' + v.prototype[t].toString();
}
}
else
fnStr += st_1;
}
else
td[k] = v;
}
return [fnStr, td];
};
var ch = [];
// clone bufs
var cbfs = function (v) {
var tl = [];
for (var k in v) {
if (v[k] instanceof u8 || v[k] instanceof u16 || v[k] instanceof u32)
tl.push((v[k] = new v[k].constructor(v[k])).buffer);
}
return tl;
};
// use a worker to execute code
var wrkr = function (fns, init, id, cb) {
var _a;
if (!ch[id]) {
var fnStr = '', td_1 = {}, m = fns.length - 1;
for (var i = 0; i < m; ++i)
_a = wcln(fns[i], fnStr, td_1), fnStr = _a[0], td_1 = _a[1];
ch[id] = wcln(fns[m], fnStr, td_1);
}
var td = mrg({}, ch[id][1]);
return wk(ch[id][0] + ';onmessage=function(e){for(var k in e.data)self[k]=e.data[k];onmessage=' + init.toString() + '}', id, td, cbfs(td), cb);
};
// base async inflate fn
var bInflt = function () { return [u8, u16, u32, fleb, fdeb, clim, fl, fd, flrm, fdrm, rev, hMap, max, bits, bits16, shft, slc, inflt, inflateSync, pbf, gu8]; };
var bDflt = function () { return [u8, u16, u32, fleb, fdeb, clim, revfl, revfd, flm, flt, fdm, fdt, rev, deo, et, hMap, wbits, wbits16, hTree, ln, lc, clen, wfblk, wblk, shft, slc, dflt, dopt, deflateSync, pbf]; };
// gzip extra
var gze = function () { return [gzh, gzhl, wbytes, crc, crct]; };
// gunzip extra
var guze = function () { return [gzs, gzl]; };
// zlib extra
var zle = function () { return [zlh, wbytes, adler]; };
// unzlib extra
var zule = function () { return [zlv]; };
// post buf
var pbf = function (msg) { return postMessage(msg, [msg.buffer]); };
// get u8
var gu8 = function (o) { return o && o.size && new u8(o.size); };
// async helper
var cbify = function (dat, opts, fns, init, id, cb) {
var w = wrkr(fns, init, id, function (err, dat) {
w.terminate();
cb(err, dat);
});
w.postMessage([dat, opts], opts.consume ? [dat.buffer] : []);
return function () { w.terminate(); };
};
// auto stream
var astrm = function (strm) {
strm.ondata = function (dat, final) { return postMessage([dat, final], [dat.buffer]); };
return function (ev) { return strm.push(ev.data[0], ev.data[1]); };
};
// async stream attach
var astrmify = function (fns, strm, opts, init, id) {
var t;
var w = wrkr(fns, init, id, function (err, dat) {
if (err)
w.terminate(), strm.ondata.call(strm, err);
else {
if (dat[1])
w.terminate();
strm.ondata.call(strm, err, dat[0], dat[1]);
}
});
w.postMessage(opts);
strm.push = function (d, f) {
if (t)
throw 'stream finished';
if (!strm.ondata)
throw 'no stream handler';
w.postMessage([d, t = f], [d.buffer]);
};
strm.terminate = function () { w.terminate(); };
};
// read 2 bytes
var b2 = function (d, b) { return d[b] | (d[b + 1] << 8); };
// read 4 bytes
var b4 = function (d, b) { return (d[b] | (d[b + 1] << 8) | (d[b + 2] << 16) | (d[b + 3] << 24)) >>> 0; };
var b8 = function (d, b) { return b4(d, b) + (b4(d, b + 4) * 4294967296); };
// write bytes
var wbytes = function (d, b, v) {
for (; v; ++b)
d[b] = v, v >>>= 8;
};
// gzip header
var gzh = function (c, o) {
var fn = o.filename;
c[0] = 31, c[1] = 139, c[2] = 8, c[8] = o.level < 2 ? 4 : o.level == 9 ? 2 : 0, c[9] = 3; // assume Unix
if (o.mtime != 0)
wbytes(c, 4, Math.floor(new Date(o.mtime || Date.now()) / 1000));
if (fn) {
c[3] = 8;
for (var i = 0; i <= fn.length; ++i)
c[i + 10] = fn.charCodeAt(i);
}
};
// gzip footer: -8 to -4 = CRC, -4 to -0 is length
// gzip start
var gzs = function (d) {
if (d[0] != 31 || d[1] != 139 || d[2] != 8)
throw 'invalid gzip data';
var flg = d[3];
var st = 10;
if (flg & 4)
st += d[10] | (d[11] << 8) + 2;
for (var zs = (flg >> 3 & 1) + (flg >> 4 & 1); zs > 0; zs -= !d[st++])
;
return st + (flg & 2);
};
// gzip length
var gzl = function (d) {
var l = d.length;
return ((d[l - 4] | d[l - 3] << 8 | d[l - 2] << 16) | (d[l - 1] << 24)) >>> 0;
};
// gzip header length
var gzhl = function (o) { return 10 + ((o.filename && (o.filename.length + 1)) || 0); };
// zlib header
var zlh = function (c, o) {
var lv = o.level, fl = lv == 0 ? 0 : lv < 6 ? 1 : lv == 9 ? 3 : 2;
c[0] = 120, c[1] = (fl << 6) | (fl ? (32 - 2 * fl) : 1);
};
// zlib valid
var zlv = function (d) {
if ((d[0] & 15) != 8 || (d[0] >>> 4) > 7 || ((d[0] << 8 | d[1]) % 31))
throw 'invalid zlib data';
if (d[1] & 32)
throw 'invalid zlib data: preset dictionaries not supported';
};
function AsyncCmpStrm(opts, cb) {
if (!cb && typeof opts == 'function')
cb = opts, opts = {};
this.ondata = cb;
return opts;
}
// zlib footer: -4 to -0 is Adler32
/**
* Streaming DEFLATE compression
*/
var Deflate = /*#__PURE__*/ (function () {
function Deflate(opts, cb) {
if (!cb && typeof opts == 'function')
cb = opts, opts = {};
this.ondata = cb;
this.o = opts || {};
}
Deflate.prototype.p = function (c, f) {
this.ondata(dopt(c, this.o, 0, 0, !f), f);
};
/**
* Pushes a chunk to be deflated
* @param chunk The chunk to push
* @param final Whether this is the last chunk
*/
Deflate.prototype.push = function (chunk, final) {
if (this.d)
throw 'stream finished';
if (!this.ondata)
throw 'no stream handler';
this.d = final;
this.p(chunk, final || false);
};
return Deflate;
}());
export { Deflate };
/**
* Asynchronous streaming DEFLATE compression
*/
var AsyncDeflate = /*#__PURE__*/ (function () {
function AsyncDeflate(opts, cb) {
astrmify([
bDflt,
function () { return [astrm, Deflate]; }
], this, AsyncCmpStrm.call(this, opts, cb), function (ev) {
var strm = new Deflate(ev.data);
onmessage = astrm(strm);
}, 6);
}
return AsyncDeflate;
}());
export { AsyncDeflate };
export function deflate(data, opts, cb) {
if (!cb)
cb = opts, opts = {};
if (typeof cb != 'function')
throw 'no callback';
return cbify(data, opts, [
bDflt,
], function (ev) { return pbf(deflateSync(ev.data[0], ev.data[1])); }, 0, cb);
}
/**
* Compresses data with DEFLATE without any wrapper
* @param data The data to compress
* @param opts The compression options
* @returns The deflated version of the data
*/
export function deflateSync(data, opts) {
return dopt(data, opts || {}, 0, 0);
}
/**
* Streaming DEFLATE decompression
*/
var Inflate = /*#__PURE__*/ (function () {
/**
* Creates an inflation stream