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function newNode() {
return {
chars: new Map(),
code: undefined,
};
}
function create(strings) {
const node = newNode();
for (let i = 0; i < strings.length; i += 1) {
const tok = strings[i];
let root = node;
for (let j = 0; j < tok.length; j += 1) {
const c = tok.charCodeAt(j);
let next = root.chars.get(c);
if (next === undefined) {
next = newNode();
root.chars.set(c, next);
}
root = next;
}
root.code = i;
}
return node;
}
function lookup(trie, str) {
let node = trie;
for (let i = 0; i < str.length; i += 1) {
if (node === undefined) {
return false;
}
node = node.chars.get(str[i]);
}
return node !== undefined && node.code !== undefined;
}
const EMPTY_UINT8_ARRAY = new Uint8Array(0);
class SmazCompress {
constructor(codebook, maxSize) {
this.trie = create(codebook);
this.buffer = new Uint8Array(maxSize);
this.verbatim = new Uint8Array(256);
}
compress(str) {
let bufferIndex = 0;
let verbatimIndex = 0;
let inputIndex = 0;
while (inputIndex < str.length) {
let indexAfterMatch = -1;
let code = -1;
let root = this.trie;
for (let j = inputIndex; j < str.length; j += 1) {
root = root.chars.get(str[j]);
if (root === undefined) {
break;
}
if (root.code !== undefined) {
code = root.code;
indexAfterMatch = j + 1;
}
}
if (code === -1) {
this.verbatim[verbatimIndex++] = str[inputIndex++];
if (verbatimIndex === 255) {
bufferIndex = this.flushVerbatim(verbatimIndex, bufferIndex);
verbatimIndex = 0;
}
}
else {
if (verbatimIndex !== 0) {
bufferIndex = this.flushVerbatim(verbatimIndex, bufferIndex);
verbatimIndex = 0;
}
this.buffer[bufferIndex++] = code;
inputIndex = indexAfterMatch;
}
}
if (verbatimIndex !== 0) {
bufferIndex = this.flushVerbatim(verbatimIndex, bufferIndex);
}
return this.buffer.slice(0, bufferIndex);
}
flushVerbatim(verbatimIndex, bufferIndex) {
if (verbatimIndex === 1) {
this.buffer[bufferIndex++] = 254;
this.buffer[bufferIndex++] = this.verbatim[0];
}
else {
this.buffer[bufferIndex++] = 255;
this.buffer[bufferIndex++] = verbatimIndex - 1;
for (let k = 0; k < verbatimIndex; k += 1) {
this.buffer[bufferIndex++] = this.verbatim[k];
}
}
return bufferIndex;
}
}
class SmazDecompress {
constructor(codebook, maxSize) {
this.codebook = codebook;
this.buffer = new Uint8Array(maxSize);
}
decompress(arr) {
let pos = 0;
let i = 0;
while (i < arr.byteLength) {
if (arr[i] === 254) {
this.buffer[pos] = arr[i + 1];
pos += 1;
i += 2;
}
else if (arr[i] === 255) {
for (let j = 0; j <= arr[i + 1]; j += 1) {
this.buffer[pos] = arr[i + 2 + j];
pos += 1;
}
i += 3 + arr[i + 1];
}
else {
for (let j = 0; j < this.codebook[arr[i]].length; j++) {
this.buffer[pos] = this.codebook[arr[i]].charCodeAt(j);
pos += 1;
}
i += 1;
}
}
return this.buffer.slice(0, pos);
}
}
const dictionary = ' ;the;e;t;a;of;o;and;i;n;s;e ;r; th; t;in;he;th;h;he ;to;\r\n;l;s ;d; a;an;er;c; o;d ;on; of;re;of ;t ;, ;is;u;at; ;n ;or;which;f;m;as;it;that;\n;was;en; ; w;es; an; i;\r;f ;g;p;nd; s;nd ;ed ;w;ed;http://;for;te;ing;y ;The; c;ti;r ;his;st; in;ar;nt;,; to;y;ng; h;with;le;al;to ;b;ou;be;were; b;se;o ;ent;ha;ng ;their;";hi;from; f;in ;de;ion;me;v;.;ve;all;re ;ri;ro;is ;co;f t;are;ea;. ;her; m;er ; p;es ;by;they;di;ra;ic;not;s, ;d t;at ;ce;la;h ;ne;as ;tio;on ;n t;io;we; a ;om;, a;s o;ur;li;ll;ch;had;this;e t;g ;e\r\n; wh;ere; co;e o;a ;us; d;ss;\n\r\n;\r\n\r;="; be; e;s a;ma;one;t t;or ;but;el;so;l ;e s;s,;no;ter; wa;iv;ho;e a; r;hat;s t;ns;ch ;wh;tr;ut;/;have;ly ;ta; ha; on;tha;-; l;ati;en ;pe; re;there;ass;si; fo;wa;ec;our;who;its;z;fo;rs;>;ot;un;<;im;th ;nc;ate;><;ver;ad; we;ly;ee; n;id; cl;ac;il;</;rt; wi;div;e, ; it;whi; ma;ge;x;e c;men;.com'.split(";");
const compressor = new SmazCompress(dictionary, 30000);
const decompressor = new SmazDecompress(dictionary, 30000);
export function compress(str) {
return compressor.compress(str);
}
export function decompress(str) {
return decompressor.decompress(str);
}