pdfjs-dist/lib/display/api.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.getDocument = getDocument;
exports.setPDFNetworkStreamFactory = setPDFNetworkStreamFactory;
exports.build = exports.version = exports.PDFPageProxy = exports.PDFDocumentProxy = exports.PDFWorker = exports.PDFDataRangeTransport = exports.LoopbackPort = void 0;

var _util = require("../shared/util.js");

var _display_utils = require("./display_utils.js");

var _font_loader = require("./font_loader.js");

var _api_compatibility = require("./api_compatibility.js");

var _canvas = require("./canvas.js");

var _worker_options = require("./worker_options.js");

var _is_node = require("../shared/is_node.js");

var _message_handler = require("../shared/message_handler.js");

var _metadata = require("./metadata.js");

var _transport_stream = require("./transport_stream.js");

var _webgl = require("./webgl.js");

const DEFAULT_RANGE_CHUNK_SIZE = 65536;
const RENDERING_CANCELLED_TIMEOUT = 100;
let createPDFNetworkStream;

function setPDFNetworkStreamFactory(pdfNetworkStreamFactory) {
  createPDFNetworkStream = pdfNetworkStreamFactory;
}

function getDocument(src) {
  const task = new PDFDocumentLoadingTask();
  let source;

  if (typeof src === "string") {
    source = {
      url: src
    };
  } else if ((0, _util.isArrayBuffer)(src)) {
    source = {
      data: src
    };
  } else if (src instanceof PDFDataRangeTransport) {
    source = {
      range: src
    };
  } else {
    if (typeof src !== "object") {
      throw new Error("Invalid parameter in getDocument, " + "need either Uint8Array, string or a parameter object");
    }

    if (!src.url && !src.data && !src.range) {
      throw new Error("Invalid parameter object: need either .data, .range or .url");
    }

    source = src;
  }

  const params = Object.create(null);
  let rangeTransport = null,
      worker = null;

  for (const key in source) {
    if (key === "url" && typeof window !== "undefined") {
      params[key] = new URL(source[key], window.location).href;
      continue;
    } else if (key === "range") {
      rangeTransport = source[key];
      continue;
    } else if (key === "worker") {
      worker = source[key];
      continue;
    } else if (key === "data" && !(source[key] instanceof Uint8Array)) {
      const pdfBytes = source[key];

      if (typeof pdfBytes === "string") {
        params[key] = (0, _util.stringToBytes)(pdfBytes);
      } else if (typeof pdfBytes === "object" && pdfBytes !== null && !isNaN(pdfBytes.length)) {
        params[key] = new Uint8Array(pdfBytes);
      } else if ((0, _util.isArrayBuffer)(pdfBytes)) {
        params[key] = new Uint8Array(pdfBytes);
      } else {
        throw new Error("Invalid PDF binary data: either typed array, " + "string or array-like object is expected in the " + "data property.");
      }

      continue;
    }

    params[key] = source[key];
  }

  params.rangeChunkSize = params.rangeChunkSize || DEFAULT_RANGE_CHUNK_SIZE;
  params.CMapReaderFactory = params.CMapReaderFactory || _display_utils.DOMCMapReaderFactory;
  params.ignoreErrors = params.stopAtErrors !== true;
  params.fontExtraProperties = params.fontExtraProperties === true;
  params.pdfBug = params.pdfBug === true;

  if (!Number.isInteger(params.maxImageSize)) {
    params.maxImageSize = -1;
  }

  if (typeof params.isEvalSupported !== "boolean") {
    params.isEvalSupported = true;
  }

  if (typeof params.disableFontFace !== "boolean") {
    params.disableFontFace = _api_compatibility.apiCompatibilityParams.disableFontFace || false;
  }

  if (typeof params.disableRange !== "boolean") {
    params.disableRange = false;
  }

  if (typeof params.disableStream !== "boolean") {
    params.disableStream = false;
  }

  if (typeof params.disableAutoFetch !== "boolean") {
    params.disableAutoFetch = false;
  }

  (0, _util.setVerbosityLevel)(params.verbosity);

  if (!worker) {
    const workerParams = {
      verbosity: params.verbosity,
      port: _worker_options.GlobalWorkerOptions.workerPort
    };
    worker = workerParams.port ? PDFWorker.fromPort(workerParams) : new PDFWorker(workerParams);
    task._worker = worker;
  }

  const docId = task.docId;
  worker.promise.then(function () {
    if (task.destroyed) {
      throw new Error("Loading aborted");
    }

    const workerIdPromise = _fetchDocument(worker, params, rangeTransport, docId);

    const networkStreamPromise = new Promise(function (resolve) {
      let networkStream;

      if (rangeTransport) {
        networkStream = new _transport_stream.PDFDataTransportStream({
          length: params.length,
          initialData: params.initialData,
          progressiveDone: params.progressiveDone,
          disableRange: params.disableRange,
          disableStream: params.disableStream
        }, rangeTransport);
      } else if (!params.data) {
        networkStream = createPDFNetworkStream({
          url: params.url,
          length: params.length,
          httpHeaders: params.httpHeaders,
          withCredentials: params.withCredentials,
          rangeChunkSize: params.rangeChunkSize,
          disableRange: params.disableRange,
          disableStream: params.disableStream
        });
      }

      resolve(networkStream);
    });
    return Promise.all([workerIdPromise, networkStreamPromise]).then(function ([workerId, networkStream]) {
      if (task.destroyed) {
        throw new Error("Loading aborted");
      }

      const messageHandler = new _message_handler.MessageHandler(docId, workerId, worker.port);
      messageHandler.postMessageTransfers = worker.postMessageTransfers;
      const transport = new WorkerTransport(messageHandler, task, networkStream, params);
      task._transport = transport;
      messageHandler.send("Ready", null);
    });
  }).catch(task._capability.reject);
  return task;
}

function _fetchDocument(worker, source, pdfDataRangeTransport, docId) {
  if (worker.destroyed) {
    return Promise.reject(new Error("Worker was destroyed"));
  }

  if (pdfDataRangeTransport) {
    source.length = pdfDataRangeTransport.length;
    source.initialData = pdfDataRangeTransport.initialData;
    source.progressiveDone = pdfDataRangeTransport.progressiveDone;
  }

  return worker.messageHandler.sendWithPromise("GetDocRequest", {
    docId,
    apiVersion: '2.5.207',
    source: {
      data: source.data,
      url: source.url,
      password: source.password,
      disableAutoFetch: source.disableAutoFetch,
      rangeChunkSize: source.rangeChunkSize,
      length: source.length
    },
    maxImageSize: source.maxImageSize,
    disableFontFace: source.disableFontFace,
    postMessageTransfers: worker.postMessageTransfers,
    docBaseUrl: source.docBaseUrl,
    ignoreErrors: source.ignoreErrors,
    isEvalSupported: source.isEvalSupported,
    fontExtraProperties: source.fontExtraProperties
  }).then(function (workerId) {
    if (worker.destroyed) {
      throw new Error("Worker was destroyed");
    }

    return workerId;
  });
}

const PDFDocumentLoadingTask = function PDFDocumentLoadingTaskClosure() {
  let nextDocumentId = 0;

  class PDFDocumentLoadingTask {
    constructor() {
      this._capability = (0, _util.createPromiseCapability)();
      this._transport = null;
      this._worker = null;
      this.docId = "d" + nextDocumentId++;
      this.destroyed = false;
      this.onPassword = null;
      this.onProgress = null;
      this.onUnsupportedFeature = null;
    }

    get promise() {
      return this._capability.promise;
    }

    destroy() {
      this.destroyed = true;
      const transportDestroyed = !this._transport ? Promise.resolve() : this._transport.destroy();
      return transportDestroyed.then(() => {
        this._transport = null;

        if (this._worker) {
          this._worker.destroy();

          this._worker = null;
        }
      });
    }

  }

  return PDFDocumentLoadingTask;
}();

class PDFDataRangeTransport {
  constructor(length, initialData, progressiveDone = false) {
    this.length = length;
    this.initialData = initialData;
    this.progressiveDone = progressiveDone;
    this._rangeListeners = [];
    this._progressListeners = [];
    this._progressiveReadListeners = [];
    this._progressiveDoneListeners = [];
    this._readyCapability = (0, _util.createPromiseCapability)();
  }

  addRangeListener(listener) {
    this._rangeListeners.push(listener);
  }

  addProgressListener(listener) {
    this._progressListeners.push(listener);
  }

  addProgressiveReadListener(listener) {
    this._progressiveReadListeners.push(listener);
  }

  addProgressiveDoneListener(listener) {
    this._progressiveDoneListeners.push(listener);
  }

  onDataRange(begin, chunk) {
    for (const listener of this._rangeListeners) {
      listener(begin, chunk);
    }
  }

  onDataProgress(loaded, total) {
    this._readyCapability.promise.then(() => {
      for (const listener of this._progressListeners) {
        listener(loaded, total);
      }
    });
  }

  onDataProgressiveRead(chunk) {
    this._readyCapability.promise.then(() => {
      for (const listener of this._progressiveReadListeners) {
        listener(chunk);
      }
    });
  }

  onDataProgressiveDone() {
    this._readyCapability.promise.then(() => {
      for (const listener of this._progressiveDoneListeners) {
        listener();
      }
    });
  }

  transportReady() {
    this._readyCapability.resolve();
  }

  requestDataRange(begin, end) {
    (0, _util.unreachable)("Abstract method PDFDataRangeTransport.requestDataRange");
  }

  abort() {}

}

exports.PDFDataRangeTransport = PDFDataRangeTransport;

class PDFDocumentProxy {
  constructor(pdfInfo, transport) {
    this._pdfInfo = pdfInfo;
    this._transport = transport;
  }

  get numPages() {
    return this._pdfInfo.numPages;
  }

  get fingerprint() {
    return this._pdfInfo.fingerprint;
  }

  getPage(pageNumber) {
    return this._transport.getPage(pageNumber);
  }

  getPageIndex(ref) {
    return this._transport.getPageIndex(ref);
  }

  getDestinations() {
    return this._transport.getDestinations();
  }

  getDestination(id) {
    return this._transport.getDestination(id);
  }

  getPageLabels() {
    return this._transport.getPageLabels();
  }

  getPageLayout() {
    return this._transport.getPageLayout();
  }

  getPageMode() {
    return this._transport.getPageMode();
  }

  getViewerPreferences() {
    return this._transport.getViewerPreferences();
  }

  getOpenAction() {
    return this._transport.getOpenAction();
  }

  getOpenActionDestination() {
    (0, _display_utils.deprecated)("getOpenActionDestination, use getOpenAction instead.");
    return this.getOpenAction().then(function (openAction) {
      return openAction && openAction.dest ? openAction.dest : null;
    });
  }

  getAttachments() {
    return this._transport.getAttachments();
  }

  getJavaScript() {
    return this._transport.getJavaScript();
  }

  getOutline() {
    return this._transport.getOutline();
  }

  getPermissions() {
    return this._transport.getPermissions();
  }

  getMetadata() {
    return this._transport.getMetadata();
  }

  getData() {
    return this._transport.getData();
  }

  getDownloadInfo() {
    return this._transport.downloadInfoCapability.promise;
  }

  getStats() {
    return this._transport.getStats();
  }

  cleanup() {
    return this._transport.startCleanup();
  }

  destroy() {
    return this.loadingTask.destroy();
  }

  get loadingParams() {
    return this._transport.loadingParams;
  }

  get loadingTask() {
    return this._transport.loadingTask;
  }

}

exports.PDFDocumentProxy = PDFDocumentProxy;

class PDFPageProxy {
  constructor(pageIndex, pageInfo, transport, pdfBug = false) {
    this._pageIndex = pageIndex;
    this._pageInfo = pageInfo;
    this._transport = transport;
    this._stats = pdfBug ? new _display_utils.StatTimer() : null;
    this._pdfBug = pdfBug;
    this.commonObjs = transport.commonObjs;
    this.objs = new PDFObjects();
    this.cleanupAfterRender = false;
    this.pendingCleanup = false;
    this.intentStates = Object.create(null);
    this.destroyed = false;
  }

  get pageNumber() {
    return this._pageIndex + 1;
  }

  get rotate() {
    return this._pageInfo.rotate;
  }

  get ref() {
    return this._pageInfo.ref;
  }

  get userUnit() {
    return this._pageInfo.userUnit;
  }

  get view() {
    return this._pageInfo.view;
  }

  getViewport({
    scale,
    rotation = this.rotate,
    offsetX = 0,
    offsetY = 0,
    dontFlip = false
  } = {}) {
    return new _display_utils.PageViewport({
      viewBox: this.view,
      scale,
      rotation,
      offsetX,
      offsetY,
      dontFlip
    });
  }

  getAnnotations({
    intent = null
  } = {}) {
    if (!this.annotationsPromise || this.annotationsIntent !== intent) {
      this.annotationsPromise = this._transport.getAnnotations(this._pageIndex, intent);
      this.annotationsIntent = intent;
    }

    return this.annotationsPromise;
  }

  render({
    canvasContext,
    viewport,
    intent = "display",
    enableWebGL = false,
    renderInteractiveForms = false,
    transform = null,
    imageLayer = null,
    canvasFactory = null,
    background = null
  }) {
    if (this._stats) {
      this._stats.time("Overall");
    }

    const renderingIntent = intent === "print" ? "print" : "display";
    this.pendingCleanup = false;

    if (!this.intentStates[renderingIntent]) {
      this.intentStates[renderingIntent] = Object.create(null);
    }

    const intentState = this.intentStates[renderingIntent];

    if (intentState.streamReaderCancelTimeout) {
      clearTimeout(intentState.streamReaderCancelTimeout);
      intentState.streamReaderCancelTimeout = null;
    }

    const canvasFactoryInstance = canvasFactory || new _display_utils.DOMCanvasFactory();
    const webGLContext = new _webgl.WebGLContext({
      enable: enableWebGL
    });

    if (!intentState.displayReadyCapability) {
      intentState.displayReadyCapability = (0, _util.createPromiseCapability)();
      intentState.operatorList = {
        fnArray: [],
        argsArray: [],
        lastChunk: false
      };

      if (this._stats) {
        this._stats.time("Page Request");
      }

      this._pumpOperatorList({
        pageIndex: this._pageIndex,
        intent: renderingIntent,
        renderInteractiveForms: renderInteractiveForms === true
      });
    }

    const complete = error => {
      const i = intentState.renderTasks.indexOf(internalRenderTask);

      if (i >= 0) {
        intentState.renderTasks.splice(i, 1);
      }

      if (this.cleanupAfterRender || renderingIntent === "print") {
        this.pendingCleanup = true;
      }

      this._tryCleanup();

      if (error) {
        internalRenderTask.capability.reject(error);

        this._abortOperatorList({
          intentState,
          reason: error
        });
      } else {
        internalRenderTask.capability.resolve();
      }

      if (this._stats) {
        this._stats.timeEnd("Rendering");

        this._stats.timeEnd("Overall");
      }
    };

    const internalRenderTask = new InternalRenderTask({
      callback: complete,
      params: {
        canvasContext,
        viewport,
        transform,
        imageLayer,
        background
      },
      objs: this.objs,
      commonObjs: this.commonObjs,
      operatorList: intentState.operatorList,
      pageIndex: this._pageIndex,
      canvasFactory: canvasFactoryInstance,
      webGLContext,
      useRequestAnimationFrame: renderingIntent !== "print",
      pdfBug: this._pdfBug
    });

    if (!intentState.renderTasks) {
      intentState.renderTasks = [];
    }

    intentState.renderTasks.push(internalRenderTask);
    const renderTask = internalRenderTask.task;
    intentState.displayReadyCapability.promise.then(transparency => {
      if (this.pendingCleanup) {
        complete();
        return;
      }

      if (this._stats) {
        this._stats.time("Rendering");
      }

      internalRenderTask.initializeGraphics(transparency);
      internalRenderTask.operatorListChanged();
    }).catch(complete);
    return renderTask;
  }

  getOperatorList() {
    function operatorListChanged() {
      if (intentState.operatorList.lastChunk) {
        intentState.opListReadCapability.resolve(intentState.operatorList);
        const i = intentState.renderTasks.indexOf(opListTask);

        if (i >= 0) {
          intentState.renderTasks.splice(i, 1);
        }
      }
    }

    const renderingIntent = "oplist";

    if (!this.intentStates[renderingIntent]) {
      this.intentStates[renderingIntent] = Object.create(null);
    }

    const intentState = this.intentStates[renderingIntent];
    let opListTask;

    if (!intentState.opListReadCapability) {
      opListTask = {};
      opListTask.operatorListChanged = operatorListChanged;
      intentState.opListReadCapability = (0, _util.createPromiseCapability)();
      intentState.renderTasks = [];
      intentState.renderTasks.push(opListTask);
      intentState.operatorList = {
        fnArray: [],
        argsArray: [],
        lastChunk: false
      };

      if (this._stats) {
        this._stats.time("Page Request");
      }

      this._pumpOperatorList({
        pageIndex: this._pageIndex,
        intent: renderingIntent
      });
    }

    return intentState.opListReadCapability.promise;
  }

  streamTextContent({
    normalizeWhitespace = false,
    disableCombineTextItems = false
  } = {}) {
    const TEXT_CONTENT_CHUNK_SIZE = 100;
    return this._transport.messageHandler.sendWithStream("GetTextContent", {
      pageIndex: this._pageIndex,
      normalizeWhitespace: normalizeWhitespace === true,
      combineTextItems: disableCombineTextItems !== true
    }, {
      highWaterMark: TEXT_CONTENT_CHUNK_SIZE,

      size(textContent) {
        return textContent.items.length;
      }

    });
  }

  getTextContent(params = {}) {
    const readableStream = this.streamTextContent(params);
    return new Promise(function (resolve, reject) {
      function pump() {
        reader.read().then(function ({
          value,
          done
        }) {
          if (done) {
            resolve(textContent);
            return;
          }

          Object.assign(textContent.styles, value.styles);
          textContent.items.push(...value.items);
          pump();
        }, reject);
      }

      const reader = readableStream.getReader();
      const textContent = {
        items: [],
        styles: Object.create(null)
      };
      pump();
    });
  }

  _destroy() {
    this.destroyed = true;
    this._transport.pageCache[this._pageIndex] = null;
    const waitOn = [];
    Object.keys(this.intentStates).forEach(intent => {
      const intentState = this.intentStates[intent];

      this._abortOperatorList({
        intentState,
        reason: new Error("Page was destroyed."),
        force: true
      });

      if (intent === "oplist") {
        return;
      }

      intentState.renderTasks.forEach(function (renderTask) {
        const renderCompleted = renderTask.capability.promise.catch(function () {});
        waitOn.push(renderCompleted);
        renderTask.cancel();
      });
    });
    this.objs.clear();
    this.annotationsPromise = null;
    this.pendingCleanup = false;
    return Promise.all(waitOn);
  }

  cleanup(resetStats = false) {
    this.pendingCleanup = true;
    return this._tryCleanup(resetStats);
  }

  _tryCleanup(resetStats = false) {
    if (!this.pendingCleanup || Object.keys(this.intentStates).some(intent => {
      const intentState = this.intentStates[intent];
      return intentState.renderTasks.length !== 0 || !intentState.operatorList.lastChunk;
    })) {
      return false;
    }

    Object.keys(this.intentStates).forEach(intent => {
      delete this.intentStates[intent];
    });
    this.objs.clear();
    this.annotationsPromise = null;

    if (resetStats && this._stats) {
      this._stats = new _display_utils.StatTimer();
    }

    this.pendingCleanup = false;
    return true;
  }

  _startRenderPage(transparency, intent) {
    const intentState = this.intentStates[intent];

    if (!intentState) {
      return;
    }

    if (this._stats) {
      this._stats.timeEnd("Page Request");
    }

    if (intentState.displayReadyCapability) {
      intentState.displayReadyCapability.resolve(transparency);
    }
  }

  _renderPageChunk(operatorListChunk, intentState) {
    for (let i = 0, ii = operatorListChunk.length; i < ii; i++) {
      intentState.operatorList.fnArray.push(operatorListChunk.fnArray[i]);
      intentState.operatorList.argsArray.push(operatorListChunk.argsArray[i]);
    }

    intentState.operatorList.lastChunk = operatorListChunk.lastChunk;

    for (let i = 0; i < intentState.renderTasks.length; i++) {
      intentState.renderTasks[i].operatorListChanged();
    }

    if (operatorListChunk.lastChunk) {
      this._tryCleanup();
    }
  }

  _pumpOperatorList(args) {
    (0, _util.assert)(args.intent, 'PDFPageProxy._pumpOperatorList: Expected "intent" argument.');

    const readableStream = this._transport.messageHandler.sendWithStream("GetOperatorList", args);

    const reader = readableStream.getReader();
    const intentState = this.intentStates[args.intent];
    intentState.streamReader = reader;

    const pump = () => {
      reader.read().then(({
        value,
        done
      }) => {
        if (done) {
          intentState.streamReader = null;
          return;
        }

        if (this._transport.destroyed) {
          return;
        }

        this._renderPageChunk(value, intentState);

        pump();
      }, reason => {
        intentState.streamReader = null;

        if (this._transport.destroyed) {
          return;
        }

        if (intentState.operatorList) {
          intentState.operatorList.lastChunk = true;

          for (let i = 0; i < intentState.renderTasks.length; i++) {
            intentState.renderTasks[i].operatorListChanged();
          }

          this._tryCleanup();
        }

        if (intentState.displayReadyCapability) {
          intentState.displayReadyCapability.reject(reason);
        } else if (intentState.opListReadCapability) {
          intentState.opListReadCapability.reject(reason);
        } else {
          throw reason;
        }
      });
    };

    pump();
  }

  _abortOperatorList({
    intentState,
    reason,
    force = false
  }) {
    (0, _util.assert)(reason instanceof Error || typeof reason === "object" && reason !== null, 'PDFPageProxy._abortOperatorList: Expected "reason" argument.');

    if (!intentState.streamReader) {
      return;
    }

    if (!force) {
      if (intentState.renderTasks.length !== 0) {
        return;
      }

      if (reason instanceof _display_utils.RenderingCancelledException) {
        intentState.streamReaderCancelTimeout = setTimeout(() => {
          this._abortOperatorList({
            intentState,
            reason,
            force: true
          });

          intentState.streamReaderCancelTimeout = null;
        }, RENDERING_CANCELLED_TIMEOUT);
        return;
      }
    }

    intentState.streamReader.cancel(new _util.AbortException(reason && reason.message));
    intentState.streamReader = null;

    if (this._transport.destroyed) {
      return;
    }

    Object.keys(this.intentStates).some(intent => {
      if (this.intentStates[intent] === intentState) {
        delete this.intentStates[intent];
        return true;
      }

      return false;
    });
    this.cleanup();
  }

  get stats() {
    return this._stats;
  }

}

exports.PDFPageProxy = PDFPageProxy;

class LoopbackPort {
  constructor(defer = true) {
    this._listeners = [];
    this._defer = defer;
    this._deferred = Promise.resolve(undefined);
  }

  postMessage(obj, transfers) {
    function cloneValue(value) {
      if (typeof value !== "object" || value === null) {
        return value;
      }

      if (cloned.has(value)) {
        return cloned.get(value);
      }

      let buffer, result;

      if ((buffer = value.buffer) && (0, _util.isArrayBuffer)(buffer)) {
        const transferable = transfers && transfers.includes(buffer);

        if (transferable) {
          result = new value.constructor(buffer, value.byteOffset, value.byteLength);
        } else {
          result = new value.constructor(value);
        }

        cloned.set(value, result);
        return result;
      }

      result = Array.isArray(value) ? [] : {};
      cloned.set(value, result);

      for (const i in value) {
        let desc,
            p = value;

        while (!(desc = Object.getOwnPropertyDescriptor(p, i))) {
          p = Object.getPrototypeOf(p);
        }

        if (typeof desc.value === "undefined") {
          continue;
        }

        if (typeof desc.value === "function") {
          if (value.hasOwnProperty && value.hasOwnProperty(i)) {
            throw new Error(`LoopbackPort.postMessage - cannot clone: ${value[i]}`);
          }

          continue;
        }

        result[i] = cloneValue(desc.value);
      }

      return result;
    }

    if (!this._defer) {
      this._listeners.forEach(listener => {
        listener.call(this, {
          data: obj
        });
      });

      return;
    }

    const cloned = new WeakMap();
    const e = {
      data: cloneValue(obj)
    };

    this._deferred.then(() => {
      this._listeners.forEach(listener => {
        listener.call(this, e);
      });
    });
  }

  addEventListener(name, listener) {
    this._listeners.push(listener);
  }

  removeEventListener(name, listener) {
    const i = this._listeners.indexOf(listener);

    this._listeners.splice(i, 1);
  }

  terminate() {
    this._listeners.length = 0;
  }

}

exports.LoopbackPort = LoopbackPort;

const PDFWorker = function PDFWorkerClosure() {
  const pdfWorkerPorts = new WeakMap();
  let isWorkerDisabled = false;
  let fallbackWorkerSrc;
  let nextFakeWorkerId = 0;
  let fakeWorkerCapability;

  if (_is_node.isNodeJS && typeof require === "function") {
    isWorkerDisabled = true;
    fallbackWorkerSrc = "../pdf.worker.js";
  } else if (typeof document === "object" && "currentScript" in document) {
    const pdfjsFilePath = document.currentScript && document.currentScript.src;

    if (pdfjsFilePath) {
      fallbackWorkerSrc = pdfjsFilePath.replace(/(\.(?:min\.)?js)(\?.*)?$/i, ".worker$1$2");
    }
  }

  function getWorkerSrc() {
    if (_worker_options.GlobalWorkerOptions.workerSrc) {
      return _worker_options.GlobalWorkerOptions.workerSrc;
    }

    if (typeof fallbackWorkerSrc !== "undefined") {
      if (!_is_node.isNodeJS) {
        (0, _display_utils.deprecated)('No "GlobalWorkerOptions.workerSrc" specified.');
      }

      return fallbackWorkerSrc;
    }

    throw new Error('No "GlobalWorkerOptions.workerSrc" specified.');
  }

  function getMainThreadWorkerMessageHandler() {
    let mainWorkerMessageHandler;

    try {
      mainWorkerMessageHandler = globalThis.pdfjsWorker && globalThis.pdfjsWorker.WorkerMessageHandler;
    } catch (ex) {}

    return mainWorkerMessageHandler || null;
  }

  function setupFakeWorkerGlobal() {
    if (fakeWorkerCapability) {
      return fakeWorkerCapability.promise;
    }

    fakeWorkerCapability = (0, _util.createPromiseCapability)();

    const loader = async function () {
      const mainWorkerMessageHandler = getMainThreadWorkerMessageHandler();

      if (mainWorkerMessageHandler) {
        return mainWorkerMessageHandler;
      }

      if (_is_node.isNodeJS && typeof require === "function") {
        const worker = eval("require")(getWorkerSrc());
        return worker.WorkerMessageHandler;
      }

      await (0, _display_utils.loadScript)(getWorkerSrc());
      return window.pdfjsWorker.WorkerMessageHandler;
    };

    loader().then(fakeWorkerCapability.resolve, fakeWorkerCapability.reject);
    return fakeWorkerCapability.promise;
  }

  function createCDNWrapper(url) {
    const wrapper = "importScripts('" + url + "');";
    return URL.createObjectURL(new Blob([wrapper]));
  }

  class PDFWorker {
    constructor({
      name = null,
      port = null,
      verbosity = (0, _util.getVerbosityLevel)()
    } = {}) {
      if (port && pdfWorkerPorts.has(port)) {
        throw new Error("Cannot use more than one PDFWorker per port");
      }

      this.name = name;
      this.destroyed = false;
      this.postMessageTransfers = true;
      this.verbosity = verbosity;
      this._readyCapability = (0, _util.createPromiseCapability)();
      this._port = null;
      this._webWorker = null;
      this._messageHandler = null;

      if (port) {
        pdfWorkerPorts.set(port, this);

        this._initializeFromPort(port);

        return;
      }

      this._initialize();
    }

    get promise() {
      return this._readyCapability.promise;
    }

    get port() {
      return this._port;
    }

    get messageHandler() {
      return this._messageHandler;
    }

    _initializeFromPort(port) {
      this._port = port;
      this._messageHandler = new _message_handler.MessageHandler("main", "worker", port);

      this._messageHandler.on("ready", function () {});

      this._readyCapability.resolve();
    }

    _initialize() {
      if (typeof Worker !== "undefined" && !isWorkerDisabled && !getMainThreadWorkerMessageHandler()) {
        let workerSrc = getWorkerSrc();

        try {
          if (!(0, _util.isSameOrigin)(window.location.href, workerSrc)) {
            workerSrc = createCDNWrapper(new URL(workerSrc, window.location).href);
          }

          const worker = new Worker(workerSrc);
          const messageHandler = new _message_handler.MessageHandler("main", "worker", worker);

          const terminateEarly = () => {
            worker.removeEventListener("error", onWorkerError);
            messageHandler.destroy();
            worker.terminate();

            if (this.destroyed) {
              this._readyCapability.reject(new Error("Worker was destroyed"));
            } else {
              this._setupFakeWorker();
            }
          };

          const onWorkerError = () => {
            if (!this._webWorker) {
              terminateEarly();
            }
          };

          worker.addEventListener("error", onWorkerError);
          messageHandler.on("test", data => {
            worker.removeEventListener("error", onWorkerError);

            if (this.destroyed) {
              terminateEarly();
              return;
            }

            if (data) {
              this._messageHandler = messageHandler;
              this._port = worker;
              this._webWorker = worker;

              if (!data.supportTransfers) {
                this.postMessageTransfers = false;
              }

              this._readyCapability.resolve();

              messageHandler.send("configure", {
                verbosity: this.verbosity
              });
            } else {
              this._setupFakeWorker();

              messageHandler.destroy();
              worker.terminate();
            }
          });
          messageHandler.on("ready", data => {
            worker.removeEventListener("error", onWorkerError);

            if (this.destroyed) {
              terminateEarly();
              return;
            }

            try {
              sendTest();
            } catch (e) {
              this._setupFakeWorker();
            }
          });

          const sendTest = () => {
            const testObj = new Uint8Array([this.postMessageTransfers ? 255 : 0]);

            try {
              messageHandler.send("test", testObj, [testObj.buffer]);
            } catch (ex) {
              (0, _util.warn)("Cannot use postMessage transfers.");
              testObj[0] = 0;
              messageHandler.send("test", testObj);
            }
          };

          sendTest();
          return;
        } catch (e) {
          (0, _util.info)("The worker has been disabled.");
        }
      }

      this._setupFakeWorker();
    }

    _setupFakeWorker() {
      if (!isWorkerDisabled) {
        (0, _util.warn)("Setting up fake worker.");
        isWorkerDisabled = true;
      }

      setupFakeWorkerGlobal().then(WorkerMessageHandler => {
        if (this.destroyed) {
          this._readyCapability.reject(new Error("Worker was destroyed"));

          return;
        }

        const port = new LoopbackPort();
        this._port = port;
        const id = "fake" + nextFakeWorkerId++;
        const workerHandler = new _message_handler.MessageHandler(id + "_worker", id, port);
        WorkerMessageHandler.setup(workerHandler, port);
        const messageHandler = new _message_handler.MessageHandler(id, id + "_worker", port);
        this._messageHandler = messageHandler;

        this._readyCapability.resolve();

        messageHandler.send("configure", {
          verbosity: this.verbosity
        });
      }).catch(reason => {
        this._readyCapability.reject(new Error(`Setting up fake worker failed: "${reason.message}".`));
      });
    }

    destroy() {
      this.destroyed = true;

      if (this._webWorker) {
        this._webWorker.terminate();

        this._webWorker = null;
      }

      pdfWorkerPorts.delete(this._port);
      this._port = null;

      if (this._messageHandler) {
        this._messageHandler.destroy();

        this._messageHandler = null;
      }
    }

    static fromPort(params) {
      if (!params || !params.port) {
        throw new Error("PDFWorker.fromPort - invalid method signature.");
      }

      if (pdfWorkerPorts.has(params.port)) {
        return pdfWorkerPorts.get(params.port);
      }

      return new PDFWorker(params);
    }

    static getWorkerSrc() {
      return getWorkerSrc();
    }

  }

  return PDFWorker;
}();

exports.PDFWorker = PDFWorker;

class WorkerTransport {
  constructor(messageHandler, loadingTask, networkStream, params) {
    this.messageHandler = messageHandler;
    this.loadingTask = loadingTask;
    this.commonObjs = new PDFObjects();
    this.fontLoader = new _font_loader.FontLoader({
      docId: loadingTask.docId,
      onUnsupportedFeature: this._onUnsupportedFeature.bind(this)
    });
    this._params = params;
    this.CMapReaderFactory = new params.CMapReaderFactory({
      baseUrl: params.cMapUrl,
      isCompressed: params.cMapPacked
    });
    this.destroyed = false;
    this.destroyCapability = null;
    this._passwordCapability = null;
    this._networkStream = networkStream;
    this._fullReader = null;
    this._lastProgress = null;
    this.pageCache = [];
    this.pagePromises = [];
    this.downloadInfoCapability = (0, _util.createPromiseCapability)();
    this.setupMessageHandler();
  }

  destroy() {
    if (this.destroyCapability) {
      return this.destroyCapability.promise;
    }

    this.destroyed = true;
    this.destroyCapability = (0, _util.createPromiseCapability)();

    if (this._passwordCapability) {
      this._passwordCapability.reject(new Error("Worker was destroyed during onPassword callback"));
    }

    const waitOn = [];
    this.pageCache.forEach(function (page) {
      if (page) {
        waitOn.push(page._destroy());
      }
    });
    this.pageCache.length = 0;
    this.pagePromises.length = 0;
    const terminated = this.messageHandler.sendWithPromise("Terminate", null);
    waitOn.push(terminated);
    Promise.all(waitOn).then(() => {
      this.fontLoader.clear();

      if (this._networkStream) {
        this._networkStream.cancelAllRequests(new _util.AbortException("Worker was terminated."));
      }

      if (this.messageHandler) {
        this.messageHandler.destroy();
        this.messageHandler = null;
      }

      this.destroyCapability.resolve();
    }, this.destroyCapability.reject);
    return this.destroyCapability.promise;
  }

  setupMessageHandler() {
    const {
      messageHandler,
      loadingTask
    } = this;
    messageHandler.on("GetReader", (data, sink) => {
      (0, _util.assert)(this._networkStream, "GetReader - no `IPDFStream` instance available.");
      this._fullReader = this._networkStream.getFullReader();

      this._fullReader.onProgress = evt => {
        this._lastProgress = {
          loaded: evt.loaded,
          total: evt.total
        };
      };

      sink.onPull = () => {
        this._fullReader.read().then(function ({
          value,
          done
        }) {
          if (done) {
            sink.close();
            return;
          }

          (0, _util.assert)((0, _util.isArrayBuffer)(value), "GetReader - expected an ArrayBuffer.");
          sink.enqueue(new Uint8Array(value), 1, [value]);
        }).catch(reason => {
          sink.error(reason);
        });
      };

      sink.onCancel = reason => {
        this._fullReader.cancel(reason);
      };
    });
    messageHandler.on("ReaderHeadersReady", data => {
      const headersCapability = (0, _util.createPromiseCapability)();
      const fullReader = this._fullReader;
      fullReader.headersReady.then(() => {
        if (!fullReader.isStreamingSupported || !fullReader.isRangeSupported) {
          if (this._lastProgress && loadingTask.onProgress) {
            loadingTask.onProgress(this._lastProgress);
          }

          fullReader.onProgress = evt => {
            if (loadingTask.onProgress) {
              loadingTask.onProgress({
                loaded: evt.loaded,
                total: evt.total
              });
            }
          };
        }

        headersCapability.resolve({
          isStreamingSupported: fullReader.isStreamingSupported,
          isRangeSupported: fullReader.isRangeSupported,
          contentLength: fullReader.contentLength
        });
      }, headersCapability.reject);
      return headersCapability.promise;
    });
    messageHandler.on("GetRangeReader", (data, sink) => {
      (0, _util.assert)(this._networkStream, "GetRangeReader - no `IPDFStream` instance available.");

      const rangeReader = this._networkStream.getRangeReader(data.begin, data.end);

      if (!rangeReader) {
        sink.close();
        return;
      }

      sink.onPull = () => {
        rangeReader.read().then(function ({
          value,
          done
        }) {
          if (done) {
            sink.close();
            return;
          }

          (0, _util.assert)((0, _util.isArrayBuffer)(value), "GetRangeReader - expected an ArrayBuffer.");
          sink.enqueue(new Uint8Array(value), 1, [value]);
        }).catch(reason => {
          sink.error(reason);
        });
      };

      sink.onCancel = reason => {
        rangeReader.cancel(reason);
      };
    });
    messageHandler.on("GetDoc", ({
      pdfInfo
    }) => {
      this._numPages = pdfInfo.numPages;

      loadingTask._capability.resolve(new PDFDocumentProxy(pdfInfo, this));
    });
    messageHandler.on("DocException", function (ex) {
      let reason;

      switch (ex.name) {
        case "PasswordException":
          reason = new _util.PasswordException(ex.message, ex.code);
          break;

        case "InvalidPDFException":
          reason = new _util.InvalidPDFException(ex.message);
          break;

        case "MissingPDFException":
          reason = new _util.MissingPDFException(ex.message);
          break;

        case "UnexpectedResponseException":
          reason = new _util.UnexpectedResponseException(ex.message, ex.status);
          break;

        case "UnknownErrorException":
          reason = new _util.UnknownErrorException(ex.message, ex.details);
          break;
      }

      loadingTask._capability.reject(reason);
    });
    messageHandler.on("PasswordRequest", exception => {
      this._passwordCapability = (0, _util.createPromiseCapability)();

      if (loadingTask.onPassword) {
        const updatePassword = password => {
          this._passwordCapability.resolve({
            password
          });
        };

        try {
          loadingTask.onPassword(updatePassword, exception.code);
        } catch (ex) {
          this._passwordCapability.reject(ex);
        }
      } else {
        this._passwordCapability.reject(new _util.PasswordException(exception.message, exception.code));
      }

      return this._passwordCapability.promise;
    });
    messageHandler.on("DataLoaded", data => {
      if (loadingTask.onProgress) {
        loadingTask.onProgress({
          loaded: data.length,
          total: data.length
        });
      }

      this.downloadInfoCapability.resolve(data);
    });
    messageHandler.on("StartRenderPage", data => {
      if (this.destroyed) {
        return;
      }

      const page = this.pageCache[data.pageIndex];

      page._startRenderPage(data.transparency, data.intent);
    });
    messageHandler.on("commonobj", data => {
      if (this.destroyed) {
        return;
      }

      const [id, type, exportedData] = data;

      if (this.commonObjs.has(id)) {
        return;
      }

      switch (type) {
        case "Font":
          const params = this._params;

          if ("error" in exportedData) {
            const exportedError = exportedData.error;
            (0, _util.warn)(`Error during font loading: ${exportedError}`);
            this.commonObjs.resolve(id, exportedError);
            break;
          }

          let fontRegistry = null;

          if (params.pdfBug && globalThis.FontInspector && globalThis.FontInspector.enabled) {
            fontRegistry = {
              registerFont(font, url) {
                globalThis.FontInspector.fontAdded(font, url);
              }

            };
          }

          const font = new _font_loader.FontFaceObject(exportedData, {
            isEvalSupported: params.isEvalSupported,
            disableFontFace: params.disableFontFace,
            ignoreErrors: params.ignoreErrors,
            onUnsupportedFeature: this._onUnsupportedFeature.bind(this),
            fontRegistry
          });
          this.fontLoader.bind(font).catch(reason => {
            return messageHandler.sendWithPromise("FontFallback", {
              id
            });
          }).finally(() => {
            if (!params.fontExtraProperties && font.data) {
              font.data = null;
            }

            this.commonObjs.resolve(id, font);
          });
          break;

        case "FontPath":
        case "FontType3Res":
        case "Image":
          this.commonObjs.resolve(id, exportedData);
          break;

        default:
          throw new Error(`Got unknown common object type ${type}`);
      }
    });
    messageHandler.on("obj", data => {
      if (this.destroyed) {
        return undefined;
      }

      const [id, pageIndex, type, imageData] = data;
      const pageProxy = this.pageCache[pageIndex];

      if (pageProxy.objs.has(id)) {
        return undefined;
      }

      switch (type) {
        case "Image":
          pageProxy.objs.resolve(id, imageData);
          const MAX_IMAGE_SIZE_TO_STORE = 8000000;

          if (imageData && "data" in imageData && imageData.data.length > MAX_IMAGE_SIZE_TO_STORE) {
            pageProxy.cleanupAfterRender = true;
          }

          break;

        default:
          throw new Error(`Got unknown object type ${type}`);
      }

      return undefined;
    });
    messageHandler.on("DocProgress", data => {
      if (this.destroyed) {
        return;
      }

      if (loadingTask.onProgress) {
        loadingTask.onProgress({
          loaded: data.loaded,
          total: data.total
        });
      }
    });
    messageHandler.on("UnsupportedFeature", this._onUnsupportedFeature.bind(this));
    messageHandler.on("FetchBuiltInCMap", (data, sink) => {
      if (this.destroyed) {
        sink.error(new Error("Worker was destroyed"));
        return;
      }

      let fetched = false;

      sink.onPull = () => {
        if (fetched) {
          sink.close();
          return;
        }

        fetched = true;
        this.CMapReaderFactory.fetch(data).then(function (builtInCMap) {
          sink.enqueue(builtInCMap, 1, [builtInCMap.cMapData.buffer]);
        }).catch(function (reason) {
          sink.error(reason);
        });
      };
    });
  }

  _onUnsupportedFeature({
    featureId
  }) {
    if (this.destroyed) {
      return;
    }

    if (this.loadingTask.onUnsupportedFeature) {
      this.loadingTask.onUnsupportedFeature(featureId);
    }
  }

  getData() {
    return this.messageHandler.sendWithPromise("GetData", null);
  }

  getPage(pageNumber) {
    if (!Number.isInteger(pageNumber) || pageNumber <= 0 || pageNumber > this._numPages) {
      return Promise.reject(new Error("Invalid page request"));
    }

    const pageIndex = pageNumber - 1;

    if (pageIndex in this.pagePromises) {
      return this.pagePromises[pageIndex];
    }

    const promise = this.messageHandler.sendWithPromise("GetPage", {
      pageIndex
    }).then(pageInfo => {
      if (this.destroyed) {
        throw new Error("Transport destroyed");
      }

      const page = new PDFPageProxy(pageIndex, pageInfo, this, this._params.pdfBug);
      this.pageCache[pageIndex] = page;
      return page;
    });
    this.pagePromises[pageIndex] = promise;
    return promise;
  }

  getPageIndex(ref) {
    return this.messageHandler.sendWithPromise("GetPageIndex", {
      ref
    }).catch(function (reason) {
      return Promise.reject(new Error(reason));
    });
  }

  getAnnotations(pageIndex, intent) {
    return this.messageHandler.sendWithPromise("GetAnnotations", {
      pageIndex,
      intent
    });
  }

  getDestinations() {
    return this.messageHandler.sendWithPromise("GetDestinations", null);
  }

  getDestination(id) {
    if (typeof id !== "string") {
      return Promise.reject(new Error("Invalid destination request."));
    }

    return this.messageHandler.sendWithPromise("GetDestination", {
      id
    });
  }

  getPageLabels() {
    return this.messageHandler.sendWithPromise("GetPageLabels", null);
  }

  getPageLayout() {
    return this.messageHandler.sendWithPromise("GetPageLayout", null);
  }

  getPageMode() {
    return this.messageHandler.sendWithPromise("GetPageMode", null);
  }

  getViewerPreferences() {
    return this.messageHandler.sendWithPromise("GetViewerPreferences", null);
  }

  getOpenAction() {
    return this.messageHandler.sendWithPromise("GetOpenAction", null);
  }

  getAttachments() {
    return this.messageHandler.sendWithPromise("GetAttachments", null);
  }

  getJavaScript() {
    return this.messageHandler.sendWithPromise("GetJavaScript", null);
  }

  getOutline() {
    return this.messageHandler.sendWithPromise("GetOutline", null);
  }

  getPermissions() {
    return this.messageHandler.sendWithPromise("GetPermissions", null);
  }

  getMetadata() {
    return this.messageHandler.sendWithPromise("GetMetadata", null).then(results => {
      return {
        info: results[0],
        metadata: results[1] ? new _metadata.Metadata(results[1]) : null,
        contentDispositionFilename: this._fullReader ? this._fullReader.filename : null
      };
    });
  }

  getStats() {
    return this.messageHandler.sendWithPromise("GetStats", null);
  }

  startCleanup() {
    return this.messageHandler.sendWithPromise("Cleanup", null).then(() => {
      for (let i = 0, ii = this.pageCache.length; i < ii; i++) {
        const page = this.pageCache[i];

        if (page) {
          const cleanupSuccessful = page.cleanup();

          if (!cleanupSuccessful) {
            throw new Error(`startCleanup: Page ${i + 1} is currently rendering.`);
          }
        }
      }

      this.commonObjs.clear();
      this.fontLoader.clear();
    });
  }

  get loadingParams() {
    const params = this._params;
    return (0, _util.shadow)(this, "loadingParams", {
      disableAutoFetch: params.disableAutoFetch,
      disableFontFace: params.disableFontFace
    });
  }

}

class PDFObjects {
  constructor() {
    this._objs = Object.create(null);
  }

  _ensureObj(objId) {
    if (this._objs[objId]) {
      return this._objs[objId];
    }

    return this._objs[objId] = {
      capability: (0, _util.createPromiseCapability)(),
      data: null,
      resolved: false
    };
  }

  get(objId, callback = null) {
    if (callback) {
      this._ensureObj(objId).capability.promise.then(callback);

      return null;
    }

    const obj = this._objs[objId];

    if (!obj || !obj.resolved) {
      throw new Error(`Requesting object that isn't resolved yet ${objId}.`);
    }

    return obj.data;
  }

  has(objId) {
    const obj = this._objs[objId];
    return obj ? obj.resolved : false;
  }

  resolve(objId, data) {
    const obj = this._ensureObj(objId);

    obj.resolved = true;
    obj.data = data;
    obj.capability.resolve(data);
  }

  clear() {
    this._objs = Object.create(null);
  }

}

class RenderTask {
  constructor(internalRenderTask) {
    this._internalRenderTask = internalRenderTask;
    this.onContinue = null;
  }

  get promise() {
    return this._internalRenderTask.capability.promise;
  }

  cancel() {
    this._internalRenderTask.cancel();
  }

}

const InternalRenderTask = function InternalRenderTaskClosure() {
  const canvasInRendering = new WeakSet();

  class InternalRenderTask {
    constructor({
      callback,
      params,
      objs,
      commonObjs,
      operatorList,
      pageIndex,
      canvasFactory,
      webGLContext,
      useRequestAnimationFrame = false,
      pdfBug = false
    }) {
      this.callback = callback;
      this.params = params;
      this.objs = objs;
      this.commonObjs = commonObjs;
      this.operatorListIdx = null;
      this.operatorList = operatorList;
      this._pageIndex = pageIndex;
      this.canvasFactory = canvasFactory;
      this.webGLContext = webGLContext;
      this._pdfBug = pdfBug;
      this.running = false;
      this.graphicsReadyCallback = null;
      this.graphicsReady = false;
      this._useRequestAnimationFrame = useRequestAnimationFrame === true && typeof window !== "undefined";
      this.cancelled = false;
      this.capability = (0, _util.createPromiseCapability)();
      this.task = new RenderTask(this);
      this._continueBound = this._continue.bind(this);
      this._scheduleNextBound = this._scheduleNext.bind(this);
      this._nextBound = this._next.bind(this);
      this._canvas = params.canvasContext.canvas;
    }

    initializeGraphics(transparency = false) {
      if (this.cancelled) {
        return;
      }

      if (this._canvas) {
        if (canvasInRendering.has(this._canvas)) {
          throw new Error("Cannot use the same canvas during multiple render() operations. " + "Use different canvas or ensure previous operations were " + "cancelled or completed.");
        }

        canvasInRendering.add(this._canvas);
      }

      if (this._pdfBug && globalThis.StepperManager && globalThis.StepperManager.enabled) {
        this.stepper = globalThis.StepperManager.create(this._pageIndex);
        this.stepper.init(this.operatorList);
        this.stepper.nextBreakPoint = this.stepper.getNextBreakPoint();
      }

      const {
        canvasContext,
        viewport,
        transform,
        imageLayer,
        background
      } = this.params;
      this.gfx = new _canvas.CanvasGraphics(canvasContext, this.commonObjs, this.objs, this.canvasFactory, this.webGLContext, imageLayer);
      this.gfx.beginDrawing({
        transform,
        viewport,
        transparency,
        background
      });
      this.operatorListIdx = 0;
      this.graphicsReady = true;

      if (this.graphicsReadyCallback) {
        this.graphicsReadyCallback();
      }
    }

    cancel(error = null) {
      this.running = false;
      this.cancelled = true;

      if (this.gfx) {
        this.gfx.endDrawing();
      }

      if (this._canvas) {
        canvasInRendering.delete(this._canvas);
      }

      this.callback(error || new _display_utils.RenderingCancelledException(`Rendering cancelled, page ${this._pageIndex + 1}`, "canvas"));
    }

    operatorListChanged() {
      if (!this.graphicsReady) {
        if (!this.graphicsReadyCallback) {
          this.graphicsReadyCallback = this._continueBound;
        }

        return;
      }

      if (this.stepper) {
        this.stepper.updateOperatorList(this.operatorList);
      }

      if (this.running) {
        return;
      }

      this._continue();
    }

    _continue() {
      this.running = true;

      if (this.cancelled) {
        return;
      }

      if (this.task.onContinue) {
        this.task.onContinue(this._scheduleNextBound);
      } else {
        this._scheduleNext();
      }
    }

    _scheduleNext() {
      if (this._useRequestAnimationFrame) {
        window.requestAnimationFrame(() => {
          this._nextBound().catch(this.cancel.bind(this));
        });
      } else {
        Promise.resolve().then(this._nextBound).catch(this.cancel.bind(this));
      }
    }

    async _next() {
      if (this.cancelled) {
        return;
      }

      this.operatorListIdx = this.gfx.executeOperatorList(this.operatorList, this.operatorListIdx, this._continueBound, this.stepper);

      if (this.operatorListIdx === this.operatorList.argsArray.length) {
        this.running = false;

        if (this.operatorList.lastChunk) {
          this.gfx.endDrawing();

          if (this._canvas) {
            canvasInRendering.delete(this._canvas);
          }

          this.callback();
        }
      }
    }

  }

  return InternalRenderTask;
}();

const version = '2.5.207';
exports.version = version;
const build = '0974d605';
exports.build = build;