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Add Base94 encode and decode operations gchq#1174 
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‎src/core/config/Categories.json

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"From Base91",
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"To Base92",
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"From Base92",
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"To Base94",
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"From Base94",
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"To Base",
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"From Base",
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"To BCD",

‎src/core/lib/Base94.mjs

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/**
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* Base94 functions.
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*
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* @author [email protected]]
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* @license Apache-2.0
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*/
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import Utils from "../Utils.mjs";
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import OperationError from "../errors/OperationError.mjs";
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/**
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* Base94's the input byte array, returning a string.
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* Every four bytes of input are converted to five bytes of
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* Base94 encoded output.
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*
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* @param {ArrayBuffer} data
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* @param {boolean} [strictLength="true"]
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* @returns {string}
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*
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* @example
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* // returns "@Z<[+/- >5$@3z&T!Qh*|F.q+ZWIz&#J<[+][[4+trr# "
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* // toBase94([48, 65, 6c, 6c, 6f, 20, 57, 6f, 72, 6c, 64, 21]);
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* // e.g. toBase94(ToHex("Hello World!"))
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*/
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export function toBase94(data, strictLength=true) {
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if (!data) return "";
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if (data instanceof ArrayBuffer) {
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data = new Uint8Array(data);
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} else {
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throw new OperationError(`Invalid - Input not instanceof ArrayBuffer.`);
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}
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const dataModLen = data.length % 4;
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if (dataModLen > 0 && strictLength) {
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throw new OperationError(`Invalid - Input byte length must be a multiple of 4.`);
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}
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let output = "", i = 0, j = 0, acc = 0;
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const dataPad = new Uint8Array(data.length + (dataModLen > 0 ? (4 - dataModLen) : 0));
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dataPad.set(data, 0);
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while (i < dataPad.length) {
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acc = 0;
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for (j = 0; j < 4; j++) {
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acc *= 256;
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acc += dataPad[i + (3 - j)];
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}
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for (j = 0; j < 5; j++) {
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output += String.fromCharCode((acc % 94)+32);
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acc = Math.floor(acc / 94);
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}
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i += 4;
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}
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return output;
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}
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/**
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* Un-Base94's the input string, returning a byte array.
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* Every five bytes of Base94 encoded input are converted to
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* four bytes of output.
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*
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* @param {string} data // Base94 encoded string
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* @param {boolean} [strictLength="true"]
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* @param {boolean} [removeInvalidChars="false"]
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* @returns {byteArray}
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*
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* @example
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* // returns [48, 65, 6c, 6c, 6f, 20, 57, 6f, 72, 6c, 64, 21]
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* // fromBase94("@Z<[+/- >5$@3z&T!Qh*|F.q+ZWIz&#J<[+][[4+trr# ", true, true);
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* // e.g. fromHex(fromBase94(....)); -> Hello World!
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*/
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export function fromBase94(data, strictLength=true, removeInvalidChars=false) {
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if (!data) {
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return [];
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}
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if (typeof data == "string") {
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data = Utils.strToByteArray(data);
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} else {
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throw new OperationError(`Invalid - typeof base94 input is not a string.`);
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}
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const re = new RegExp("[^\x20-\x7e]", "g");
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if (re.test(data)) {
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if (removeInvalidChars) {
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data = data.replace(re, "");
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} else {
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throw new OperationError(`Invalid content in Base94 string.`);
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}
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}
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let stringModLen = data.length % 5;
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if (stringModLen > 0) {
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if (strictLength) {
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throw new OperationError(`Invalid - Input string length must be a multiple of 5.`);
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}
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stringModLen = 5 - stringModLen;
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while (stringModLen > 0) {
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data.push(32);
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stringModLen -= 1;
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}
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}
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const output = [];
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let i = 0, j = 0, acc = 0;
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while (i < data.length) {
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acc = 0;
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for (j = 0; j < 5; j++) {
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acc = (acc * 94) + data[i + 4 - j] - 32;
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}
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for (j = 0; j < 4; j++) {
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output.push(acc % 256);
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acc = Math.floor(acc / 256);
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}
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i += 5;
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}
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return output;
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}

‎src/core/operations/FromBase94.mjs

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/**
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* @author [email protected]]
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* @license Apache-2.0
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*/
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import Operation from "../Operation.mjs";
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import {fromBase94} from "../lib/Base94.mjs";
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/**
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* From Base94 operation
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*/
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class FromBase94 extends Operation {
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/**
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* FromBase94 constructor
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*/
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constructor() {
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super();
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this.name = "From Base94";
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this.module = "Default";
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this.description = "Base94 is a notation for encoding arbitrary byte data using a restricted set of symbols and is found primarily in the finance/ATM technology space.<br/><br/>This operation decodes an ASCII Base94 string returning a byteArray.<br/><br/>e.g. <code>@Z<[+/- >5$@3z&T!Qh*|F.q+ZWIz&#J<[+][[4+trr# </code> becomes <code>[48, 65, 6c, 6c, 6f, 20, 57, 6f, 72, 6c, 64, 21]</code><br/><br/>This is a no frills, no soft toilet paper implementation. It's string in, byteArray out.<br/><br/>By default, input length is expected to by a multiple of 5. Unchecking 'Strict length' will pad non mod 5 length input with space(s).<br/><br/>Base94 encoded content is expected to be in ASCII range '0x20 thru 0x7e'. Leaving 'Remove Invalid Chars' unchecked will enforce this.";
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this.inputType = "string";
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this.outputType = "byteArray";
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this.args = [
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{
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name: "Strict length",
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type: "boolean",
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value: true
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},
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{
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name: "Remove Invalid Chars",
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type: "boolean",
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value: false
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}
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];
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}
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/**
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* @param {string} input
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* @param {Object[]} args
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* @returns {byteArray}
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*/
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run(input, args) {
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const [strictLength, removeInvalidChars] = args;
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return fromBase94(input, strictLength, removeInvalidChars);
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}
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/**
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* Highlight to Base94
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*
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* @param {Object[]} pos
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* @param {number} pos[].start
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* @param {number} pos[].end
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* @param {Object[]} args
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* @returns {Object[]} pos
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*/
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highlight(pos, args) {
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pos[0].start = Math.ceil(pos[0].start / 4 * 5);
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pos[0].end = Math.floor(pos[0].end / 4 * 5);
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return pos;
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}
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/**
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* Highlight from Base94
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*
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* @param {Object[]} pos
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* @param {number} pos[].start
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* @param {number} pos[].end
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* @param {Object[]} args
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* @returns {Object[]} pos
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*/
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highlightReverse(pos, args) {
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pos[0].start = Math.floor(pos[0].start / 5 * 4);
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pos[0].end = Math.ceil(pos[0].end / 5 * 4);
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return pos;
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}
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}
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export default FromBase94;

‎src/core/operations/ToBase94.mjs

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/**
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* @author [email protected]]
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* @license Apache-2.0
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*/
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import Operation from "../Operation.mjs";
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import {toBase94} from "../lib/Base94.mjs";
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/**
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* To Base64 operation
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*/
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class ToBase94 extends Operation {
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/**
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* ToBase94 constructor
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*/
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constructor() {
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super();
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this.name = "To Base94";
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this.module = "Default";
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this.description = "Base94 is a notation for encoding arbitrary byte data using a restricted set of symbols and is found primarily in the finance/ATM technology space.<br/><br/>This operation encodes raw data into an ASCII Base94 string.<br/><br/>e.g. <code>[48, 65, 6c, 6c, 6f, 20, 57, 6f, 72, 6c, 64, 21]</code> becomes <code>@Z<[+/- >5$@3z&T!Qh*|F.q+ZWIz&#J<[+][[4+trr# </code><br/><br/>This is a no frills, no soft toilet paper implementation. It's ArrayBuffer in, string out.<br/><br/>By default, input length is expected to by a multiple of 4. Unchecking 'Strict length' will pad non mod 4 length input with zero(es).";
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this.inputType = "ArrayBuffer";
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this.outputType = "string";
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this.args = [
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{
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name: "Strict length",
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type: "boolean",
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value: true
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}
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];
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}
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/**
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* @param {ArrayBuffer} input
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* @param {Object[]} args
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* @returns {string}
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*/
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run(input, args) {
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const [strictLength] = args;
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return toBase94(input, strictLength);
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}
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/**
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* Highlight to Base94
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*
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* @param {Object[]} pos
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* @param {number} pos[].start
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* @param {number} pos[].end
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* @param {Object[]} args
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* @returns {Object[]} pos
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*/
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highlight(pos, args) {
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pos[0].start = Math.floor(pos[0].start / 4 * 5);
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pos[0].end = Math.ceil(pos[0].end / 4 * 5);
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return pos;
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}
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/**
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* Highlight from Base94
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*
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* @param {Object[]} pos
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* @param {number} pos[].start
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* @param {number} pos[].end
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* @param {Object[]} args
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* @returns {Object[]} pos
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*/
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highlightReverse(pos, args) {
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pos[0].start = Math.ceil(pos[0].start / 5 * 4);
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pos[0].end = Math.floor(pos[0].end / 5 * 4);
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return pos;
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}
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}
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export default ToBase94;

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