pdfjs-dist/lib/shared/util.js

/**
 * @licstart The following is the entire license notice for the
 * Javascript code in this page
 *
 * Copyright 2020 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * @licend The above is the entire license notice for the
 * Javascript code in this page
 */
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.arrayByteLength = arrayByteLength;
exports.arraysToBytes = arraysToBytes;
exports.assert = assert;
exports.bytesToString = bytesToString;
exports.createPromiseCapability = createPromiseCapability;
exports.getVerbosityLevel = getVerbosityLevel;
exports.info = info;
exports.isArrayBuffer = isArrayBuffer;
exports.isArrayEqual = isArrayEqual;
exports.isBool = isBool;
exports.isEmptyObj = isEmptyObj;
exports.isNum = isNum;
exports.isString = isString;
exports.isSameOrigin = isSameOrigin;
exports.createValidAbsoluteUrl = createValidAbsoluteUrl;
exports.removeNullCharacters = removeNullCharacters;
exports.setVerbosityLevel = setVerbosityLevel;
exports.shadow = shadow;
exports.string32 = string32;
exports.stringToBytes = stringToBytes;
exports.stringToPDFString = stringToPDFString;
exports.stringToUTF8String = stringToUTF8String;
exports.utf8StringToString = utf8StringToString;
exports.warn = warn;
exports.unreachable = unreachable;
exports.IsEvalSupportedCached = exports.IsLittleEndianCached = exports.createObjectURL = exports.FormatError = exports.Util = exports.UnknownErrorException = exports.UnexpectedResponseException = exports.TextRenderingMode = exports.StreamType = exports.PermissionFlag = exports.PasswordResponses = exports.PasswordException = exports.NativeImageDecoding = exports.MissingPDFException = exports.InvalidPDFException = exports.AbortException = exports.CMapCompressionType = exports.ImageKind = exports.FontType = exports.AnnotationType = exports.AnnotationStateModelType = exports.AnnotationReviewState = exports.AnnotationReplyType = exports.AnnotationMarkedState = exports.AnnotationFlag = exports.AnnotationFieldFlag = exports.AnnotationBorderStyleType = exports.UNSUPPORTED_FEATURES = exports.VerbosityLevel = exports.OPS = exports.IDENTITY_MATRIX = exports.FONT_IDENTITY_MATRIX = exports.BaseException = void 0;

require("./compatibility.js");

const IDENTITY_MATRIX = [1, 0, 0, 1, 0, 0];
exports.IDENTITY_MATRIX = IDENTITY_MATRIX;
const FONT_IDENTITY_MATRIX = [0.001, 0, 0, 0.001, 0, 0];
exports.FONT_IDENTITY_MATRIX = FONT_IDENTITY_MATRIX;
const NativeImageDecoding = {
  NONE: "none",
  DECODE: "decode",
  DISPLAY: "display"
};
exports.NativeImageDecoding = NativeImageDecoding;
const PermissionFlag = {
  PRINT: 0x04,
  MODIFY_CONTENTS: 0x08,
  COPY: 0x10,
  MODIFY_ANNOTATIONS: 0x20,
  FILL_INTERACTIVE_FORMS: 0x100,
  COPY_FOR_ACCESSIBILITY: 0x200,
  ASSEMBLE: 0x400,
  PRINT_HIGH_QUALITY: 0x800
};
exports.PermissionFlag = PermissionFlag;
const TextRenderingMode = {
  FILL: 0,
  STROKE: 1,
  FILL_STROKE: 2,
  INVISIBLE: 3,
  FILL_ADD_TO_PATH: 4,
  STROKE_ADD_TO_PATH: 5,
  FILL_STROKE_ADD_TO_PATH: 6,
  ADD_TO_PATH: 7,
  FILL_STROKE_MASK: 3,
  ADD_TO_PATH_FLAG: 4
};
exports.TextRenderingMode = TextRenderingMode;
const ImageKind = {
  GRAYSCALE_1BPP: 1,
  RGB_24BPP: 2,
  RGBA_32BPP: 3
};
exports.ImageKind = ImageKind;
const AnnotationType = {
  TEXT: 1,
  LINK: 2,
  FREETEXT: 3,
  LINE: 4,
  SQUARE: 5,
  CIRCLE: 6,
  POLYGON: 7,
  POLYLINE: 8,
  HIGHLIGHT: 9,
  UNDERLINE: 10,
  SQUIGGLY: 11,
  STRIKEOUT: 12,
  STAMP: 13,
  CARET: 14,
  INK: 15,
  POPUP: 16,
  FILEATTACHMENT: 17,
  SOUND: 18,
  MOVIE: 19,
  WIDGET: 20,
  SCREEN: 21,
  PRINTERMARK: 22,
  TRAPNET: 23,
  WATERMARK: 24,
  THREED: 25,
  REDACT: 26
};
exports.AnnotationType = AnnotationType;
const AnnotationStateModelType = {
  MARKED: "Marked",
  REVIEW: "Review"
};
exports.AnnotationStateModelType = AnnotationStateModelType;
const AnnotationMarkedState = {
  MARKED: "Marked",
  UNMARKED: "Unmarked"
};
exports.AnnotationMarkedState = AnnotationMarkedState;
const AnnotationReviewState = {
  ACCEPTED: "Accepted",
  REJECTED: "Rejected",
  CANCELLED: "Cancelled",
  COMPLETED: "Completed",
  NONE: "None"
};
exports.AnnotationReviewState = AnnotationReviewState;
const AnnotationReplyType = {
  GROUP: "Group",
  REPLY: "R"
};
exports.AnnotationReplyType = AnnotationReplyType;
const AnnotationFlag = {
  INVISIBLE: 0x01,
  HIDDEN: 0x02,
  PRINT: 0x04,
  NOZOOM: 0x08,
  NOROTATE: 0x10,
  NOVIEW: 0x20,
  READONLY: 0x40,
  LOCKED: 0x80,
  TOGGLENOVIEW: 0x100,
  LOCKEDCONTENTS: 0x200
};
exports.AnnotationFlag = AnnotationFlag;
const AnnotationFieldFlag = {
  READONLY: 0x0000001,
  REQUIRED: 0x0000002,
  NOEXPORT: 0x0000004,
  MULTILINE: 0x0001000,
  PASSWORD: 0x0002000,
  NOTOGGLETOOFF: 0x0004000,
  RADIO: 0x0008000,
  PUSHBUTTON: 0x0010000,
  COMBO: 0x0020000,
  EDIT: 0x0040000,
  SORT: 0x0080000,
  FILESELECT: 0x0100000,
  MULTISELECT: 0x0200000,
  DONOTSPELLCHECK: 0x0400000,
  DONOTSCROLL: 0x0800000,
  COMB: 0x1000000,
  RICHTEXT: 0x2000000,
  RADIOSINUNISON: 0x2000000,
  COMMITONSELCHANGE: 0x4000000
};
exports.AnnotationFieldFlag = AnnotationFieldFlag;
const AnnotationBorderStyleType = {
  SOLID: 1,
  DASHED: 2,
  BEVELED: 3,
  INSET: 4,
  UNDERLINE: 5
};
exports.AnnotationBorderStyleType = AnnotationBorderStyleType;
const StreamType = {
  UNKNOWN: "UNKNOWN",
  FLATE: "FLATE",
  LZW: "LZW",
  DCT: "DCT",
  JPX: "JPX",
  JBIG: "JBIG",
  A85: "A85",
  AHX: "AHX",
  CCF: "CCF",
  RLX: "RLX"
};
exports.StreamType = StreamType;
const FontType = {
  UNKNOWN: "UNKNOWN",
  TYPE1: "TYPE1",
  TYPE1C: "TYPE1C",
  CIDFONTTYPE0: "CIDFONTTYPE0",
  CIDFONTTYPE0C: "CIDFONTTYPE0C",
  TRUETYPE: "TRUETYPE",
  CIDFONTTYPE2: "CIDFONTTYPE2",
  TYPE3: "TYPE3",
  OPENTYPE: "OPENTYPE",
  TYPE0: "TYPE0",
  MMTYPE1: "MMTYPE1"
};
exports.FontType = FontType;
const VerbosityLevel = {
  ERRORS: 0,
  WARNINGS: 1,
  INFOS: 5
};
exports.VerbosityLevel = VerbosityLevel;
const CMapCompressionType = {
  NONE: 0,
  BINARY: 1,
  STREAM: 2
};
exports.CMapCompressionType = CMapCompressionType;
const OPS = {
  dependency: 1,
  setLineWidth: 2,
  setLineCap: 3,
  setLineJoin: 4,
  setMiterLimit: 5,
  setDash: 6,
  setRenderingIntent: 7,
  setFlatness: 8,
  setGState: 9,
  save: 10,
  restore: 11,
  transform: 12,
  moveTo: 13,
  lineTo: 14,
  curveTo: 15,
  curveTo2: 16,
  curveTo3: 17,
  closePath: 18,
  rectangle: 19,
  stroke: 20,
  closeStroke: 21,
  fill: 22,
  eoFill: 23,
  fillStroke: 24,
  eoFillStroke: 25,
  closeFillStroke: 26,
  closeEOFillStroke: 27,
  endPath: 28,
  clip: 29,
  eoClip: 30,
  beginText: 31,
  endText: 32,
  setCharSpacing: 33,
  setWordSpacing: 34,
  setHScale: 35,
  setLeading: 36,
  setFont: 37,
  setTextRenderingMode: 38,
  setTextRise: 39,
  moveText: 40,
  setLeadingMoveText: 41,
  setTextMatrix: 42,
  nextLine: 43,
  showText: 44,
  showSpacedText: 45,
  nextLineShowText: 46,
  nextLineSetSpacingShowText: 47,
  setCharWidth: 48,
  setCharWidthAndBounds: 49,
  setStrokeColorSpace: 50,
  setFillColorSpace: 51,
  setStrokeColor: 52,
  setStrokeColorN: 53,
  setFillColor: 54,
  setFillColorN: 55,
  setStrokeGray: 56,
  setFillGray: 57,
  setStrokeRGBColor: 58,
  setFillRGBColor: 59,
  setStrokeCMYKColor: 60,
  setFillCMYKColor: 61,
  shadingFill: 62,
  beginInlineImage: 63,
  beginImageData: 64,
  endInlineImage: 65,
  paintXObject: 66,
  markPoint: 67,
  markPointProps: 68,
  beginMarkedContent: 69,
  beginMarkedContentProps: 70,
  endMarkedContent: 71,
  beginCompat: 72,
  endCompat: 73,
  paintFormXObjectBegin: 74,
  paintFormXObjectEnd: 75,
  beginGroup: 76,
  endGroup: 77,
  beginAnnotations: 78,
  endAnnotations: 79,
  beginAnnotation: 80,
  endAnnotation: 81,
  paintJpegXObject: 82,
  paintImageMaskXObject: 83,
  paintImageMaskXObjectGroup: 84,
  paintImageXObject: 85,
  paintInlineImageXObject: 86,
  paintInlineImageXObjectGroup: 87,
  paintImageXObjectRepeat: 88,
  paintImageMaskXObjectRepeat: 89,
  paintSolidColorImageMask: 90,
  constructPath: 91
};
exports.OPS = OPS;
const UNSUPPORTED_FEATURES = {
  unknown: "unknown",
  forms: "forms",
  javaScript: "javaScript",
  smask: "smask",
  shadingPattern: "shadingPattern",
  font: "font"
};
exports.UNSUPPORTED_FEATURES = UNSUPPORTED_FEATURES;
const PasswordResponses = {
  NEED_PASSWORD: 1,
  INCORRECT_PASSWORD: 2
};
exports.PasswordResponses = PasswordResponses;
let verbosity = VerbosityLevel.WARNINGS;

function setVerbosityLevel(level) {
  if (Number.isInteger(level)) {
    verbosity = level;
  }
}

function getVerbosityLevel() {
  return verbosity;
}

function info(msg) {
  if (verbosity >= VerbosityLevel.INFOS) {
    console.log(`Info: ${msg}`);
  }
}

function warn(msg) {
  if (verbosity >= VerbosityLevel.WARNINGS) {
    console.log(`Warning: ${msg}`);
  }
}

function unreachable(msg) {
  throw new Error(msg);
}

function assert(cond, msg) {
  if (!cond) {
    unreachable(msg);
  }
}

function isSameOrigin(baseUrl, otherUrl) {
  let base;

  try {
    base = new URL(baseUrl);

    if (!base.origin || base.origin === "null") {
      return false;
    }
  } catch (e) {
    return false;
  }

  const other = new URL(otherUrl, base);
  return base.origin === other.origin;
}

function _isValidProtocol(url) {
  if (!url) {
    return false;
  }

  switch (url.protocol) {
    case "http:":
    case "https:":
    case "ftp:":
    case "mailto:":
    case "tel:":
      return true;

    default:
      return false;
  }
}

function createValidAbsoluteUrl(url, baseUrl) {
  if (!url) {
    return null;
  }

  try {
    const absoluteUrl = baseUrl ? new URL(url, baseUrl) : new URL(url);

    if (_isValidProtocol(absoluteUrl)) {
      return absoluteUrl;
    }
  } catch (ex) {}

  return null;
}

function shadow(obj, prop, value) {
  Object.defineProperty(obj, prop, {
    value,
    enumerable: true,
    configurable: true,
    writable: false
  });
  return value;
}

const BaseException = function BaseExceptionClosure() {
  function BaseException(message) {
    if (this.constructor === BaseException) {
      unreachable("Cannot initialize BaseException.");
    }

    this.message = message;
    this.name = this.constructor.name;
  }

  BaseException.prototype = new Error();
  BaseException.constructor = BaseException;
  return BaseException;
}();

exports.BaseException = BaseException;

class PasswordException extends BaseException {
  constructor(msg, code) {
    super(msg);
    this.code = code;
  }

}

exports.PasswordException = PasswordException;

class UnknownErrorException extends BaseException {
  constructor(msg, details) {
    super(msg);
    this.details = details;
  }

}

exports.UnknownErrorException = UnknownErrorException;

class InvalidPDFException extends BaseException {}

exports.InvalidPDFException = InvalidPDFException;

class MissingPDFException extends BaseException {}

exports.MissingPDFException = MissingPDFException;

class UnexpectedResponseException extends BaseException {
  constructor(msg, status) {
    super(msg);
    this.status = status;
  }

}

exports.UnexpectedResponseException = UnexpectedResponseException;

class FormatError extends BaseException {}

exports.FormatError = FormatError;

class AbortException extends BaseException {}

exports.AbortException = AbortException;
const NullCharactersRegExp = /\x00/g;

function removeNullCharacters(str) {
  if (typeof str !== "string") {
    warn("The argument for removeNullCharacters must be a string.");
    return str;
  }

  return str.replace(NullCharactersRegExp, "");
}

function bytesToString(bytes) {
  assert(bytes !== null && typeof bytes === "object" && bytes.length !== undefined, "Invalid argument for bytesToString");
  const length = bytes.length;
  const MAX_ARGUMENT_COUNT = 8192;

  if (length < MAX_ARGUMENT_COUNT) {
    return String.fromCharCode.apply(null, bytes);
  }

  const strBuf = [];

  for (let i = 0; i < length; i += MAX_ARGUMENT_COUNT) {
    const chunkEnd = Math.min(i + MAX_ARGUMENT_COUNT, length);
    const chunk = bytes.subarray(i, chunkEnd);
    strBuf.push(String.fromCharCode.apply(null, chunk));
  }

  return strBuf.join("");
}

function stringToBytes(str) {
  assert(typeof str === "string", "Invalid argument for stringToBytes");
  const length = str.length;
  const bytes = new Uint8Array(length);

  for (let i = 0; i < length; ++i) {
    bytes[i] = str.charCodeAt(i) & 0xff;
  }

  return bytes;
}

function arrayByteLength(arr) {
  if (arr.length !== undefined) {
    return arr.length;
  }

  assert(arr.byteLength !== undefined);
  return arr.byteLength;
}

function arraysToBytes(arr) {
  const length = arr.length;

  if (length === 1 && arr[0] instanceof Uint8Array) {
    return arr[0];
  }

  let resultLength = 0;

  for (let i = 0; i < length; i++) {
    resultLength += arrayByteLength(arr[i]);
  }

  let pos = 0;
  const data = new Uint8Array(resultLength);

  for (let i = 0; i < length; i++) {
    let item = arr[i];

    if (!(item instanceof Uint8Array)) {
      if (typeof item === "string") {
        item = stringToBytes(item);
      } else {
        item = new Uint8Array(item);
      }
    }

    const itemLength = item.byteLength;
    data.set(item, pos);
    pos += itemLength;
  }

  return data;
}

function string32(value) {
  return String.fromCharCode(value >> 24 & 0xff, value >> 16 & 0xff, value >> 8 & 0xff, value & 0xff);
}

function isLittleEndian() {
  const buffer8 = new Uint8Array(4);
  buffer8[0] = 1;
  const view32 = new Uint32Array(buffer8.buffer, 0, 1);
  return view32[0] === 1;
}

const IsLittleEndianCached = {
  get value() {
    return shadow(this, "value", isLittleEndian());
  }

};
exports.IsLittleEndianCached = IsLittleEndianCached;

function isEvalSupported() {
  try {
    new Function("");
    return true;
  } catch (e) {
    return false;
  }
}

const IsEvalSupportedCached = {
  get value() {
    return shadow(this, "value", isEvalSupported());
  }

};
exports.IsEvalSupportedCached = IsEvalSupportedCached;
const rgbBuf = ["rgb(", 0, ",", 0, ",", 0, ")"];

class Util {
  static makeCssRgb(r, g, b) {
    rgbBuf[1] = r;
    rgbBuf[3] = g;
    rgbBuf[5] = b;
    return rgbBuf.join("");
  }

  static transform(m1, m2) {
    return [m1[0] * m2[0] + m1[2] * m2[1], m1[1] * m2[0] + m1[3] * m2[1], m1[0] * m2[2] + m1[2] * m2[3], m1[1] * m2[2] + m1[3] * m2[3], m1[0] * m2[4] + m1[2] * m2[5] + m1[4], m1[1] * m2[4] + m1[3] * m2[5] + m1[5]];
  }

  static applyTransform(p, m) {
    const xt = p[0] * m[0] + p[1] * m[2] + m[4];
    const yt = p[0] * m[1] + p[1] * m[3] + m[5];
    return [xt, yt];
  }

  static applyInverseTransform(p, m) {
    const d = m[0] * m[3] - m[1] * m[2];
    const xt = (p[0] * m[3] - p[1] * m[2] + m[2] * m[5] - m[4] * m[3]) / d;
    const yt = (-p[0] * m[1] + p[1] * m[0] + m[4] * m[1] - m[5] * m[0]) / d;
    return [xt, yt];
  }

  static getAxialAlignedBoundingBox(r, m) {
    const p1 = Util.applyTransform(r, m);
    const p2 = Util.applyTransform(r.slice(2, 4), m);
    const p3 = Util.applyTransform([r[0], r[3]], m);
    const p4 = Util.applyTransform([r[2], r[1]], m);
    return [Math.min(p1[0], p2[0], p3[0], p4[0]), Math.min(p1[1], p2[1], p3[1], p4[1]), Math.max(p1[0], p2[0], p3[0], p4[0]), Math.max(p1[1], p2[1], p3[1], p4[1])];
  }

  static inverseTransform(m) {
    const d = m[0] * m[3] - m[1] * m[2];
    return [m[3] / d, -m[1] / d, -m[2] / d, m[0] / d, (m[2] * m[5] - m[4] * m[3]) / d, (m[4] * m[1] - m[5] * m[0]) / d];
  }

  static apply3dTransform(m, v) {
    return [m[0] * v[0] + m[1] * v[1] + m[2] * v[2], m[3] * v[0] + m[4] * v[1] + m[5] * v[2], m[6] * v[0] + m[7] * v[1] + m[8] * v[2]];
  }

  static singularValueDecompose2dScale(m) {
    const transpose = [m[0], m[2], m[1], m[3]];
    const a = m[0] * transpose[0] + m[1] * transpose[2];
    const b = m[0] * transpose[1] + m[1] * transpose[3];
    const c = m[2] * transpose[0] + m[3] * transpose[2];
    const d = m[2] * transpose[1] + m[3] * transpose[3];
    const first = (a + d) / 2;
    const second = Math.sqrt((a + d) * (a + d) - 4 * (a * d - c * b)) / 2;
    const sx = first + second || 1;
    const sy = first - second || 1;
    return [Math.sqrt(sx), Math.sqrt(sy)];
  }

  static normalizeRect(rect) {
    const r = rect.slice(0);

    if (rect[0] > rect[2]) {
      r[0] = rect[2];
      r[2] = rect[0];
    }

    if (rect[1] > rect[3]) {
      r[1] = rect[3];
      r[3] = rect[1];
    }

    return r;
  }

  static intersect(rect1, rect2) {
    function compare(a, b) {
      return a - b;
    }

    const orderedX = [rect1[0], rect1[2], rect2[0], rect2[2]].sort(compare);
    const orderedY = [rect1[1], rect1[3], rect2[1], rect2[3]].sort(compare);
    const result = [];
    rect1 = Util.normalizeRect(rect1);
    rect2 = Util.normalizeRect(rect2);

    if (orderedX[0] === rect1[0] && orderedX[1] === rect2[0] || orderedX[0] === rect2[0] && orderedX[1] === rect1[0]) {
      result[0] = orderedX[1];
      result[2] = orderedX[2];
    } else {
      return null;
    }

    if (orderedY[0] === rect1[1] && orderedY[1] === rect2[1] || orderedY[0] === rect2[1] && orderedY[1] === rect1[1]) {
      result[1] = orderedY[1];
      result[3] = orderedY[2];
    } else {
      return null;
    }

    return result;
  }

}

exports.Util = Util;
const PDFStringTranslateTable = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x2D8, 0x2C7, 0x2C6, 0x2D9, 0x2DD, 0x2DB, 0x2DA, 0x2DC, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x2022, 0x2020, 0x2021, 0x2026, 0x2014, 0x2013, 0x192, 0x2044, 0x2039, 0x203A, 0x2212, 0x2030, 0x201E, 0x201C, 0x201D, 0x2018, 0x2019, 0x201A, 0x2122, 0xFB01, 0xFB02, 0x141, 0x152, 0x160, 0x178, 0x17D, 0x131, 0x142, 0x153, 0x161, 0x17E, 0, 0x20AC];

function stringToPDFString(str) {
  const length = str.length,
        strBuf = [];

  if (str[0] === "\xFE" && str[1] === "\xFF") {
    for (let i = 2; i < length; i += 2) {
      strBuf.push(String.fromCharCode(str.charCodeAt(i) << 8 | str.charCodeAt(i + 1)));
    }
  } else if (str[0] === "\xFF" && str[1] === "\xFE") {
    for (let i = 2; i < length; i += 2) {
      strBuf.push(String.fromCharCode(str.charCodeAt(i + 1) << 8 | str.charCodeAt(i)));
    }
  } else {
    for (let i = 0; i < length; ++i) {
      const code = PDFStringTranslateTable[str.charCodeAt(i)];
      strBuf.push(code ? String.fromCharCode(code) : str.charAt(i));
    }
  }

  return strBuf.join("");
}

function stringToUTF8String(str) {
  return decodeURIComponent(escape(str));
}

function utf8StringToString(str) {
  return unescape(encodeURIComponent(str));
}

function isEmptyObj(obj) {
  for (const key in obj) {
    return false;
  }

  return true;
}

function isBool(v) {
  return typeof v === "boolean";
}

function isNum(v) {
  return typeof v === "number";
}

function isString(v) {
  return typeof v === "string";
}

function isArrayBuffer(v) {
  return typeof v === "object" && v !== null && v.byteLength !== undefined;
}

function isArrayEqual(arr1, arr2) {
  if (arr1.length !== arr2.length) {
    return false;
  }

  return arr1.every(function (element, index) {
    return element === arr2[index];
  });
}

function createPromiseCapability() {
  const capability = Object.create(null);
  let isSettled = false;
  Object.defineProperty(capability, "settled", {
    get() {
      return isSettled;
    }

  });
  capability.promise = new Promise(function (resolve, reject) {
    capability.resolve = function (data) {
      isSettled = true;
      resolve(data);
    };

    capability.reject = function (reason) {
      isSettled = true;
      reject(reason);
    };
  });
  return capability;
}

const createObjectURL = function createObjectURLClosure() {
  const digits = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
  return function createObjectURL(data, contentType, forceDataSchema = false) {
    if (!forceDataSchema && URL.createObjectURL) {
      const blob = new Blob([data], {
        type: contentType
      });
      return URL.createObjectURL(blob);
    }

    let buffer = `data:${contentType};base64,`;

    for (let i = 0, ii = data.length; i < ii; i += 3) {
      const b1 = data[i] & 0xff;
      const b2 = data[i + 1] & 0xff;
      const b3 = data[i + 2] & 0xff;
      const d1 = b1 >> 2,
            d2 = (b1 & 3) << 4 | b2 >> 4;
      const d3 = i + 1 < ii ? (b2 & 0xf) << 2 | b3 >> 6 : 64;
      const d4 = i + 2 < ii ? b3 & 0x3f : 64;
      buffer += digits[d1] + digits[d2] + digits[d3] + digits[d4];
    }

    return buffer;
  };
}();

exports.createObjectURL = createObjectURL;