mirror of
https://github.com/jackyzha0/quartz.git
synced 2025-12-24 13:24:05 -06:00
53 lines
1.5 KiB
JavaScript
53 lines
1.5 KiB
JavaScript
const Bytes = require("./bytes");
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const inis = "pbtdkgxjfvlrmnsz".split("");
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const mids = "auie".split("");
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const back = [inis, mids].map(chars => {
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let map = {};
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for (let i = 0; i < chars.length; ++i) map[chars[i]] = i;
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return map;
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});
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const syllableFromB64 = b64 => {
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const ini = b64 >>> 2 & 15;
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const mid = b64 >>> 0 & 3;
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return inis[ini] + mids[mid];
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};
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const syllableToB64 = syllable => {
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const ini = back[0][syllable[0]];
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const mid = back[1][syllable[1]];
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return ini * 4 + mid;
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};
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const b64sFromBytes = bytes => {
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//BoooooBoooooBoooooBooooo
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//BoooooooBoooooooBooooooo
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let b64s = [],
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b64;
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for (let i = 0, l = Math.ceil(bytes.length * 8 / 6); i < l; ++i) {
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let j = i / 8 * 6 | 0;
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b64s.push(i % 4 === 0 ? bytes[j + 0] / 4 | 0 : i % 4 === 1 ? bytes[j + 0] % 4 * 16 + (bytes[j + 1] / 16 | 0) : i % 4 === 2 ? bytes[j + 0] % 16 * 4 + (bytes[j + 1] / 64 | 0) : bytes[j + 0] % 64 * 1);
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}
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return b64s;
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};
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const b64sToBytes = b64s => {
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let bytes = [];
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for (let i = 0, l = Math.floor(b64s.length * 6 / 8); i < l; ++i) {
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let j = i / 6 * 8 | 0;
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bytes.push(i % 3 === 0 ? b64s[j + 0] % 64 * 4 + (b64s[j + 1] / 16 | 0) : i % 3 === 1 ? b64s[j + 0] % 16 * 16 + (b64s[j + 1] / 4 | 0) : b64s[j + 0] % 4 * 64 + (b64s[j + 1] / 1 | 0));
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}
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return bytes;
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};
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const fromBytes = bytes => b64sFromBytes(Bytes.toArray(bytes)).map(syllableFromB64).join("");
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const toBytes = syllables => Bytes.fromArray(b64sToBytes(syllables.match(/\w\w/g).map(syllableToB64)));
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module.exports = {
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fromBytes,
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toBytes
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}; |