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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
/** * {@linkcode encode} and {@linkcode decode} for * [base64](https://en.wikipedia.org/wiki/Base64) encoding. * * This module is browser compatible. * * @example * ```ts * import { *   decode, *   encode, * } from "https://deno.land/std@$STD_VERSION/encoding/base64.ts"; * * const b64Repr = "Zm9vYg=="; * * const binaryData = decode(b64Repr); * console.log(binaryData); * // => Uint8Array [ 102, 111, 111, 98 ] * * console.log(encode(binaryData)); * // => Zm9vYg== * ``` * * @module */
const base64abc = [  "A",  "B",  "C",  "D",  "E",  "F",  "G",  "H",  "I",  "J",  "K",  "L",  "M",  "N",  "O",  "P",  "Q",  "R",  "S",  "T",  "U",  "V",  "W",  "X",  "Y",  "Z",  "a",  "b",  "c",  "d",  "e",  "f",  "g",  "h",  "i",  "j",  "k",  "l",  "m",  "n",  "o",  "p",  "q",  "r",  "s",  "t",  "u",  "v",  "w",  "x",  "y",  "z",  "0",  "1",  "2",  "3",  "4",  "5",  "6",  "7",  "8",  "9",  "+",  "/",];
/** * CREDIT: https://gist.github.com/enepomnyaschih/72c423f727d395eeaa09697058238727 * Encodes a given Uint8Array, ArrayBuffer or string into RFC4648 base64 representation * @param data */export function encode(data: ArrayBuffer | string): string {  const uint8 = typeof data === "string"    ? new TextEncoder().encode(data)    : data instanceof Uint8Array    ? data    : new Uint8Array(data);  let result = "",    i;  const l = uint8.length;  for (i = 2; i < l; i += 3) {    result += base64abc[uint8[i - 2] >> 2];    result += base64abc[((uint8[i - 2] & 0x03) << 4) | (uint8[i - 1] >> 4)];    result += base64abc[((uint8[i - 1] & 0x0f) << 2) | (uint8[i] >> 6)];    result += base64abc[uint8[i] & 0x3f];  }  if (i === l + 1) {    // 1 octet yet to write    result += base64abc[uint8[i - 2] >> 2];    result += base64abc[(uint8[i - 2] & 0x03) << 4];    result += "==";  }  if (i === l) {    // 2 octets yet to write    result += base64abc[uint8[i - 2] >> 2];    result += base64abc[((uint8[i - 2] & 0x03) << 4) | (uint8[i - 1] >> 4)];    result += base64abc[(uint8[i - 1] & 0x0f) << 2];    result += "=";  }  return result;}
/** * Decodes a given RFC4648 base64 encoded string * @param b64 */export function decode(b64: string): Uint8Array {  const binString = atob(b64);  const size = binString.length;  const bytes = new Uint8Array(size);  for (let i = 0; i < size; i++) {    bytes[i] = binString.charCodeAt(i);  }  return bytes;}