text: // MIT License
  //
  // Copyright (c) 2012 Universidad Politécnica de Madrid
  //
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  //
  // The above copyright notice and this permission notice shall be included in all
  // copies or substantial portions of the Software.
  //
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  // SOFTWARE.
  
  // Copyright (C) <2018> Intel Corporation
  //
  // SPDX-License-Identifier: Apache-2.0
  
  // This file is borrowed from lynckia/licode with some modifications.
  
  'use strict';
  export const Base64 = (function() {
    const END_OF_INPUT = -1;
    let base64Str;
    let base64Count;
  
    let i;
  
    const base64Chars = [
      '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', '+', '/',
    ];
  
    const reverseBase64Chars = [];
  
    for (i = 0; i < base64Chars.length; i = i + 1) {
      reverseBase64Chars[base64Chars[i]] = i;
    }
  
    const setBase64Str = function(str) {
      base64Str = str;
      base64Count = 0;
    };
  
    const readBase64 = function() {
      if (!base64Str) {
        return END_OF_INPUT;
      }
      if (base64Count >= base64Str.length) {
        return END_OF_INPUT;
      }
      const c = base64Str.charCodeAt(base64Count) & 0xff;
      base64Count = base64Count + 1;
      return c;
    };
  
    const encodeBase64 = function(str) {
      let result;
      let done;
      setBase64Str(str);
      result = '';
      const inBuffer = new Array(3);
      done = false;
      while (!done && (inBuffer[0] = readBase64()) !== END_OF_INPUT) {
        inBuffer[1] = readBase64();
        inBuffer[2] = readBase64();
        result = result + (base64Chars[inBuffer[0] >> 2]);
        if (inBuffer[1] !== END_OF_INPUT) {
          result = result + (base64Chars[((inBuffer[0] << 4) & 0x30) | (
            inBuffer[1] >> 4)]);
          if (inBuffer[2] !== END_OF_INPUT) {
            result = result + (base64Chars[((inBuffer[1] << 2) & 0x3c) | (
              inBuffer[2] >> 6)]);
            result = result + (base64Chars[inBuffer[2] & 0x3F]);
          } else {
            result = result + (base64Chars[((inBuffer[1] << 2) & 0x3c)]);
            result = result + ('=');
            done = true;
          }
        } else {
          result = result + (base64Chars[((inBuffer[0] << 4) & 0x30)]);
          result = result + ('=');
          result = result + ('=');
          done = true;
        }
      }
      return result;
    };
  
    const readReverseBase64 = function() {
      if (!base64Str) {
        return END_OF_INPUT;
      }
      while (true) { // eslint-disable-line no-constant-condition
        if (base64Count >= base64Str.length) {
          return END_OF_INPUT;
        }
        const nextCharacter = base64Str.charAt(base64Count);
        base64Count = base64Count + 1;
        if (reverseBase64Chars[nextCharacter]) {
          return reverseBase64Chars[nextCharacter];
        }
        if (nextCharacter === 'A') {
          return 0;
        }
      }
    };
  
    const ntos = function(n) {
      n = n.toString(16);
      if (n.length === 1) {
        n = '0' + n;
      }
      n = '%' + n;
      return unescape(n);
    };
  
    const decodeBase64 = function(str) {
      let result;
      let done;
      setBase64Str(str);
      result = '';
      const inBuffer = new Array(4);
      done = false;
      while (!done && (inBuffer[0] = readReverseBase64()) !== END_OF_INPUT &&
        (inBuffer[1] = readReverseBase64()) !== END_OF_INPUT) {
        inBuffer[2] = readReverseBase64();
        inBuffer[3] = readReverseBase64();
        result = result + ntos((((inBuffer[0] << 2) & 0xff) | inBuffer[1] >>
          4));
        if (inBuffer[2] !== END_OF_INPUT) {
          result += ntos((((inBuffer[1] << 4) & 0xff) | inBuffer[2] >> 2));
          if (inBuffer[3] !== END_OF_INPUT) {
            result = result + ntos((((inBuffer[2] << 6) & 0xff) | inBuffer[
                3]));
          } else {
            done = true;
          }
        } else {
          done = true;
        }
      }
      return result;
    };
  
    return {
      encodeBase64: encodeBase64,
      decodeBase64: decodeBase64,
    };
  }());
  