pdfjs-vue-print/pdf.js/web/app.js

Example Vue 3 project using pdf.js to build a simple custom PDF.js viewer and print service.

/* Copyright 2012 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.
 */

import {
  animationStarted,
  apiPageLayoutToViewerModes,
  apiPageModeToSidebarView,
  AutoPrintRegExp,
  DEFAULT_SCALE_VALUE,
  getActiveOrFocusedElement,
  isValidRotation,
  isValidScrollMode,
  isValidSpreadMode,
  normalizeWheelEventDirection,
  parseQueryString,
  ProgressBar,
  RendererType,
  RenderingStates,
  ScrollMode,
  SidebarView,
  SpreadMode,
  TextLayerMode,
} from "./ui_utils.js";
import {
  AnnotationEditorType,
  build,
  createPromiseCapability,
  getDocument,
  getFilenameFromUrl,
  getPdfFilenameFromUrl,
  GlobalWorkerOptions,
  InvalidPDFException,
  isPdfFile,
  loadScript,
  MissingPDFException,
  OPS,
  PDFWorker,
  shadow,
  UnexpectedResponseException,
  UNSUPPORTED_FEATURES,
  version,
} from "pdfjs-lib";
import { AppOptions, OptionKind } from "./app_options.js";
import { AutomationEventBus, EventBus } from "./event_utils.js";
import { CursorTool, PDFCursorTools } from "./pdf_cursor_tools.js";
import { LinkTarget, PDFLinkService } from "./pdf_link_service.js";
import { AnnotationEditorParams } from "./annotation_editor_params.js";
import { OverlayManager } from "./overlay_manager.js";
import { PasswordPrompt } from "./password_prompt.js";
import { PDFAttachmentViewer } from "./pdf_attachment_viewer.js";
import { PDFDocumentProperties } from "./pdf_document_properties.js";
import { PDFFindBar } from "./pdf_find_bar.js";
import { PDFFindController } from "./pdf_find_controller.js";
import { PDFHistory } from "./pdf_history.js";
import { PDFLayerViewer } from "./pdf_layer_viewer.js";
import { PDFOutlineViewer } from "./pdf_outline_viewer.js";
import { PDFPresentationMode } from "./pdf_presentation_mode.js";
import { PDFRenderingQueue } from "./pdf_rendering_queue.js";
import { PDFScriptingManager } from "./pdf_scripting_manager.js";
import { PDFSidebar } from "./pdf_sidebar.js";
import { PDFSidebarResizer } from "./pdf_sidebar_resizer.js";
import { PDFThumbnailViewer } from "./pdf_thumbnail_viewer.js";
import { PDFViewer } from "./pdf_viewer.js";
import { SecondaryToolbar } from "./secondary_toolbar.js";
import { Toolbar } from "./toolbar.js";
import { ViewHistory } from "./view_history.js";

const DISABLE_AUTO_FETCH_LOADING_BAR_TIMEOUT = 5000; // ms
const FORCE_PAGES_LOADED_TIMEOUT = 10000; // ms
const WHEEL_ZOOM_DISABLED_TIMEOUT = 1000; // ms

const ViewOnLoad = {
  UNKNOWN: -1,
  PREVIOUS: 0, // Default value.
  INITIAL: 1,
};

const ViewerCssTheme = {
  AUTOMATIC: 0, // Default value.
  LIGHT: 1,
  DARK: 2,
};

// Keep these in sync with mozilla-central's Histograms.json.
const KNOWN_VERSIONS = [
  "1.0",
  "1.1",
  "1.2",
  "1.3",
  "1.4",
  "1.5",
  "1.6",
  "1.7",
  "1.8",
  "1.9",
  "2.0",
  "2.1",
  "2.2",
  "2.3",
];
// Keep these in sync with mozilla-central's Histograms.json.
const KNOWN_GENERATORS = [
  "acrobat distiller",
  "acrobat pdfwriter",
  "adobe livecycle",
  "adobe pdf library",
  "adobe photoshop",
  "ghostscript",
  "tcpdf",
  "cairo",
  "dvipdfm",
  "dvips",
  "pdftex",
  "pdfkit",
  "itext",
  "prince",
  "quarkxpress",
  "mac os x",
  "microsoft",
  "openoffice",
  "oracle",
  "luradocument",
  "pdf-xchange",
  "antenna house",
  "aspose.cells",
  "fpdf",
];

class DefaultExternalServices {
  constructor() {
    throw new Error("Cannot initialize DefaultExternalServices.");
  }

  static updateFindControlState(data) {}

  static updateFindMatchesCount(data) {}

  static initPassiveLoading(callbacks) {}

  static reportTelemetry(data) {}

  static createDownloadManager(options) {
    throw new Error("Not implemented: createDownloadManager");
  }

  static createPreferences() {
    throw new Error("Not implemented: createPreferences");
  }

  static createL10n(options) {
    throw new Error("Not implemented: createL10n");
  }

  static createScripting(options) {
    throw new Error("Not implemented: createScripting");
  }

  static get supportsIntegratedFind() {
    return shadow(this, "supportsIntegratedFind", false);
  }

  static get supportsDocumentFonts() {
    return shadow(this, "supportsDocumentFonts", true);
  }

  static get supportedMouseWheelZoomModifierKeys() {
    return shadow(this, "supportedMouseWheelZoomModifierKeys", {
      ctrlKey: true,
      metaKey: true,
    });
  }

  static get isInAutomation() {
    return shadow(this, "isInAutomation", false);
  }

  static updateEditorStates(data) {
    throw new Error("Not implemented: updateEditorStates");
  }
}

const PDFViewerApplication = {
  initialBookmark: document.location.hash.substring(1),
  _initializedCapability: createPromiseCapability(),
  appConfig: null,
  pdfDocument: null,
  pdfLoadingTask: null,
  printService: null,
  /** @type {PDFViewer} */
  pdfViewer: null,
  /** @type {PDFThumbnailViewer} */
  pdfThumbnailViewer: null,
  /** @type {PDFRenderingQueue} */
  pdfRenderingQueue: null,
  /** @type {PDFPresentationMode} */
  pdfPresentationMode: null,
  /** @type {PDFDocumentProperties} */
  pdfDocumentProperties: null,
  /** @type {PDFLinkService} */
  pdfLinkService: null,
  /** @type {PDFHistory} */
  pdfHistory: null,
  /** @type {PDFSidebar} */
  pdfSidebar: null,
  /** @type {PDFSidebarResizer} */
  pdfSidebarResizer: null,
  /** @type {PDFOutlineViewer} */
  pdfOutlineViewer: null,
  /** @type {PDFAttachmentViewer} */
  pdfAttachmentViewer: null,
  /** @type {PDFLayerViewer} */
  pdfLayerViewer: null,
  /** @type {PDFCursorTools} */
  pdfCursorTools: null,
  /** @type {PDFScriptingManager} */
  pdfScriptingManager: null,
  /** @type {ViewHistory} */
  store: null,
  /** @type {DownloadManager} */
  downloadManager: null,
  /** @type {OverlayManager} */
  overlayManager: null,
  /** @type {Preferences} */
  preferences: null,
  /** @type {Toolbar} */
  toolbar: null,
  /** @type {SecondaryToolbar} */
  secondaryToolbar: null,
  /** @type {EventBus} */
  eventBus: null,
  /** @type {IL10n} */
  l10n: null,
  /** @type {AnnotationEditorParams} */
  annotationEditorParams: null,
  isInitialViewSet: false,
  downloadComplete: false,
  isViewerEmbedded: window.parent !== window,
  url: "",
  baseUrl: "",
  _downloadUrl: "",
  externalServices: DefaultExternalServices,
  _boundEvents: Object.create(null),
  documentInfo: null,
  metadata: null,
  _contentDispositionFilename: null,
  _contentLength: null,
  _saveInProgress: false,
  _docStats: null,
  _wheelUnusedTicks: 0,
  _PDFBug: null,
  _hasAnnotationEditors: false,
  _title: document.title,
  _printAnnotationStoragePromise: null,

  // Called once when the document is loaded.
  async initialize(appConfig) {
    this.preferences = this.externalServices.createPreferences();
    this.appConfig = appConfig;

    await this._readPreferences();
    await this._parseHashParameters();
    this._forceCssTheme();
    await this._initializeL10n();

    if (
      this.isViewerEmbedded &&
      AppOptions.get("externalLinkTarget") === LinkTarget.NONE
    ) {
      // Prevent external links from "replacing" the viewer,
      // when it's embedded in e.g. an <iframe> or an <object>.
      AppOptions.set("externalLinkTarget", LinkTarget.TOP);
    }
    await this._initializeViewerComponents();

    // Bind the various event handlers *after* the viewer has been
    // initialized, to prevent errors if an event arrives too soon.
    this.bindEvents();
    this.bindWindowEvents();

    // We can start UI localization now.
    const appContainer = appConfig.appContainer || document.documentElement;
    this.l10n.translate(appContainer).then(() => {
      // Dispatch the 'localized' event on the `eventBus` once the viewer
      // has been fully initialized and translated.
      this.eventBus.dispatch("localized", { source: this });
    });

    this._initializedCapability.resolve();
  },

  /**
   * @private
   */
  async _readPreferences() {
    if (
      typeof PDFJSDev === "undefined" ||
      PDFJSDev.test("!PRODUCTION || GENERIC")
    ) {
      if (AppOptions.get("disablePreferences")) {
        // Give custom implementations of the default viewer a simpler way to
        // opt-out of having the `Preferences` override existing `AppOptions`.
        return;
      }
      if (AppOptions._hasUserOptions()) {
        console.warn(
          "_readPreferences: The Preferences may override manually set AppOptions; " +
            'please use the "disablePreferences"-option in order to prevent that.'
        );
      }
    }
    try {
      AppOptions.setAll(await this.preferences.getAll());
    } catch (reason) {
      console.error(`_readPreferences: "${reason?.message}".`);
    }
  },

  /**
   * Potentially parse special debugging flags in the hash section of the URL.
   * @private
   */
  async _parseHashParameters() {
    if (!AppOptions.get("pdfBugEnabled")) {
      return;
    }
    const hash = document.location.hash.substring(1);
    if (!hash) {
      return;
    }
    const { mainContainer, viewerContainer } = this.appConfig,
      params = parseQueryString(hash);

    if (params.get("disableworker") === "true") {
      try {
        await loadFakeWorker();
      } catch (ex) {
        console.error(`_parseHashParameters: "${ex.message}".`);
      }
    }
    if (params.has("disablerange")) {
      AppOptions.set("disableRange", params.get("disablerange") === "true");
    }
    if (params.has("disablestream")) {
      AppOptions.set("disableStream", params.get("disablestream") === "true");
    }
    if (params.has("disableautofetch")) {
      AppOptions.set(
        "disableAutoFetch",
        params.get("disableautofetch") === "true"
      );
    }
    if (params.has("disablefontface")) {
      AppOptions.set(
        "disableFontFace",
        params.get("disablefontface") === "true"
      );
    }
    if (params.has("disablehistory")) {
      AppOptions.set("disableHistory", params.get("disablehistory") === "true");
    }
    if (params.has("verbosity")) {
      AppOptions.set("verbosity", params.get("verbosity") | 0);
    }
    if (params.has("textlayer")) {
      switch (params.get("textlayer")) {
        case "off":
          AppOptions.set("textLayerMode", TextLayerMode.DISABLE);
          break;
        case "visible":
        case "shadow":
        case "hover":
          viewerContainer.classList.add(`textLayer-${params.get("textlayer")}`);
          try {
            await loadPDFBug(this);
            this._PDFBug.loadCSS();
          } catch (ex) {
            console.error(`_parseHashParameters: "${ex.message}".`);
          }
          break;
      }
    }
    if (params.has("pdfbug")) {
      AppOptions.set("pdfBug", true);
      AppOptions.set("fontExtraProperties", true);

      const enabled = params.get("pdfbug").split(",");
      try {
        await loadPDFBug(this);
        this._PDFBug.init({ OPS }, mainContainer, enabled);
      } catch (ex) {
        console.error(`_parseHashParameters: "${ex.message}".`);
      }
    }
    // It is not possible to change locale for the (various) extension builds.
    if (
      (typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")) &&
      params.has("locale")
    ) {
      AppOptions.set("locale", params.get("locale"));
    }
  },

  /**
   * @private
   */
  async _initializeL10n() {
    this.l10n = this.externalServices.createL10n(
      typeof PDFJSDev === "undefined" || PDFJSDev.test("!PRODUCTION || GENERIC")
        ? { locale: AppOptions.get("locale") }
        : null
    );
    const dir = await this.l10n.getDirection();
    document.getElementsByTagName("html")[0].dir = dir;
  },

  /**
   * @private
   */
  _forceCssTheme() {
    const cssTheme = AppOptions.get("viewerCssTheme");
    if (
      cssTheme === ViewerCssTheme.AUTOMATIC ||
      !Object.values(ViewerCssTheme).includes(cssTheme)
    ) {
      return;
    }
    try {
      const styleSheet = document.styleSheets[0];
      const cssRules = styleSheet?.cssRules || [];
      for (let i = 0, ii = cssRules.length; i < ii; i++) {
        const rule = cssRules[i];
        if (
          rule instanceof CSSMediaRule &&
          rule.media?.[0] === "(prefers-color-scheme: dark)"
        ) {
          if (cssTheme === ViewerCssTheme.LIGHT) {
            styleSheet.deleteRule(i);
            return;
          }
          // cssTheme === ViewerCssTheme.DARK
          const darkRules =
            /^@media \(prefers-color-scheme: dark\) {\n\s*([\w\s-.,:;/\\{}()]+)\n}$/.exec(
              rule.cssText
            );
          if (darkRules?.[1]) {
            styleSheet.deleteRule(i);
            styleSheet.insertRule(darkRules[1], i);
          }
          return;
        }
      }
    } catch (reason) {
      console.error(`_forceCssTheme: "${reason?.message}".`);
    }
  },

  /**
   * @private
   */
  async _initializeViewerComponents() {
    const { appConfig, externalServices } = this;

    const eventBus = externalServices.isInAutomation
      ? new AutomationEventBus()
      : new EventBus();
    this.eventBus = eventBus;

    this.overlayManager = new OverlayManager();

    const pdfRenderingQueue = new PDFRenderingQueue();
    pdfRenderingQueue.onIdle = this._cleanup.bind(this);
    this.pdfRenderingQueue = pdfRenderingQueue;

    const pdfLinkService = new PDFLinkService({
      eventBus,
      externalLinkTarget: AppOptions.get("externalLinkTarget"),
      externalLinkRel: AppOptions.get("externalLinkRel"),
      ignoreDestinationZoom: AppOptions.get("ignoreDestinationZoom"),
    });
    this.pdfLinkService = pdfLinkService;

    const downloadManager = externalServices.createDownloadManager();
    this.downloadManager = downloadManager;

    const findController = new PDFFindController({
      linkService: pdfLinkService,
      eventBus,
    });
    this.findController = findController;

    const pdfScriptingManager = new PDFScriptingManager({
      eventBus,
      sandboxBundleSrc:
        typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC || CHROME")
          ? AppOptions.get("sandboxBundleSrc")
          : null,
      scriptingFactory: externalServices,
      docPropertiesLookup: this._scriptingDocProperties.bind(this),
    });
    this.pdfScriptingManager = pdfScriptingManager;

    const container = appConfig.mainContainer,
      viewer = appConfig.viewerContainer;
    const annotationEditorMode = AppOptions.get("annotationEditorMode");
    const pageColors =
      AppOptions.get("forcePageColors") ||
      window.matchMedia("(forced-colors: active)").matches
        ? {
            background: AppOptions.get("pageColorsBackground"),
            foreground: AppOptions.get("pageColorsForeground"),
          }
        : null;

    this.pdfViewer = new PDFViewer({
      container,
      viewer,
      eventBus,
      renderingQueue: pdfRenderingQueue,
      linkService: pdfLinkService,
      downloadManager,
      findController,
      scriptingManager:
        AppOptions.get("enableScripting") && pdfScriptingManager,
      renderer:
        typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")
          ? AppOptions.get("renderer")
          : null,
      l10n: this.l10n,
      textLayerMode: AppOptions.get("textLayerMode"),
      annotationMode: AppOptions.get("annotationMode"),
      annotationEditorMode,
      imageResourcesPath: AppOptions.get("imageResourcesPath"),
      enablePrintAutoRotate: AppOptions.get("enablePrintAutoRotate"),
      useOnlyCssZoom: AppOptions.get("useOnlyCssZoom"),
      maxCanvasPixels: AppOptions.get("maxCanvasPixels"),
      enablePermissions: AppOptions.get("enablePermissions"),
      pageColors,
    });
    pdfRenderingQueue.setViewer(this.pdfViewer);
    pdfLinkService.setViewer(this.pdfViewer);
    pdfScriptingManager.setViewer(this.pdfViewer);

    this.pdfThumbnailViewer = new PDFThumbnailViewer({
      container: appConfig.sidebar.thumbnailView,
      eventBus,
      renderingQueue: pdfRenderingQueue,
      linkService: pdfLinkService,
      l10n: this.l10n,
      pageColors,
    });
    pdfRenderingQueue.setThumbnailViewer(this.pdfThumbnailViewer);

    // The browsing history is only enabled when the viewer is standalone,
    // i.e. not when it is embedded in a web page.
    if (!this.isViewerEmbedded && !AppOptions.get("disableHistory")) {
      this.pdfHistory = new PDFHistory({
        linkService: pdfLinkService,
        eventBus,
      });
      pdfLinkService.setHistory(this.pdfHistory);
    }

    if (!this.supportsIntegratedFind) {
      this.findBar = new PDFFindBar(appConfig.findBar, eventBus, this.l10n);
    }

    if (annotationEditorMode !== AnnotationEditorType.DISABLE) {
      this.annotationEditorParams = new AnnotationEditorParams(
        appConfig.annotationEditorParams,
        eventBus
      );
    } else {
      for (const element of [
        document.getElementById("editorModeButtons"),
        document.getElementById("editorModeSeparator"),
      ]) {
        element.hidden = true;
      }
    }

    this.pdfDocumentProperties = new PDFDocumentProperties(
      appConfig.documentProperties,
      this.overlayManager,
      eventBus,
      this.l10n,
      /* fileNameLookup = */ () => {
        return this._docFilename;
      }
    );

    this.pdfCursorTools = new PDFCursorTools({
      container,
      eventBus,
      cursorToolOnLoad: AppOptions.get("cursorToolOnLoad"),
    });

    this.toolbar = new Toolbar(appConfig.toolbar, eventBus, this.l10n);

    this.secondaryToolbar = new SecondaryToolbar(
      appConfig.secondaryToolbar,
      eventBus,
      this.externalServices
    );

    if (this.supportsFullscreen) {
      this.pdfPresentationMode = new PDFPresentationMode({
        container,
        pdfViewer: this.pdfViewer,
        eventBus,
      });
    }

    this.passwordPrompt = new PasswordPrompt(
      appConfig.passwordOverlay,
      this.overlayManager,
      this.l10n,
      this.isViewerEmbedded
    );

    this.pdfOutlineViewer = new PDFOutlineViewer({
      container: appConfig.sidebar.outlineView,
      eventBus,
      linkService: pdfLinkService,
      downloadManager,
    });

    this.pdfAttachmentViewer = new PDFAttachmentViewer({
      container: appConfig.sidebar.attachmentsView,
      eventBus,
      downloadManager,
    });

    this.pdfLayerViewer = new PDFLayerViewer({
      container: appConfig.sidebar.layersView,
      eventBus,
      l10n: this.l10n,
    });

    this.pdfSidebar = new PDFSidebar({
      elements: appConfig.sidebar,
      pdfViewer: this.pdfViewer,
      pdfThumbnailViewer: this.pdfThumbnailViewer,
      eventBus,
      l10n: this.l10n,
    });
    this.pdfSidebar.onToggled = this.forceRendering.bind(this);

    this.pdfSidebarResizer = new PDFSidebarResizer(
      appConfig.sidebarResizer,
      eventBus,
      this.l10n
    );
  },

  run(config) {
    this.initialize(config).then(webViewerInitialized);
  },

  get initialized() {
    return this._initializedCapability.settled;
  },

  get initializedPromise() {
    return this._initializedCapability.promise;
  },

  zoomIn(steps) {
    if (this.pdfViewer.isInPresentationMode) {
      return;
    }
    this.pdfViewer.increaseScale(steps);
  },

  zoomOut(steps) {
    if (this.pdfViewer.isInPresentationMode) {
      return;
    }
    this.pdfViewer.decreaseScale(steps);
  },

  zoomReset() {
    if (this.pdfViewer.isInPresentationMode) {
      return;
    }
    this.pdfViewer.currentScaleValue = DEFAULT_SCALE_VALUE;
  },

  get pagesCount() {
    return this.pdfDocument ? this.pdfDocument.numPages : 0;
  },

  get page() {
    return this.pdfViewer.currentPageNumber;
  },

  set page(val) {
    this.pdfViewer.currentPageNumber = val;
  },

  get supportsPrinting() {
    return PDFPrintServiceFactory.instance.supportsPrinting;
  },

  get supportsFullscreen() {
    return shadow(this, "supportsFullscreen", document.fullscreenEnabled);
  },

  get supportsIntegratedFind() {
    return this.externalServices.supportsIntegratedFind;
  },

  get supportsDocumentFonts() {
    return this.externalServices.supportsDocumentFonts;
  },

  get loadingBar() {
    const bar = new ProgressBar("loadingBar");
    return shadow(this, "loadingBar", bar);
  },

  get supportedMouseWheelZoomModifierKeys() {
    return this.externalServices.supportedMouseWheelZoomModifierKeys;
  },

  initPassiveLoading() {
    if (
      typeof PDFJSDev === "undefined" ||
      !PDFJSDev.test("MOZCENTRAL || CHROME")
    ) {
      throw new Error("Not implemented: initPassiveLoading");
    }
    this.externalServices.initPassiveLoading({
      onOpenWithTransport: (url, length, transport) => {
        this.open(url, { length, range: transport });
      },
      onOpenWithData: (data, contentDispositionFilename) => {
        if (isPdfFile(contentDispositionFilename)) {
          this._contentDispositionFilename = contentDispositionFilename;
        }
        this.open(data);
      },
      onOpenWithURL: (url, length, originalUrl) => {
        const file = originalUrl !== undefined ? { url, originalUrl } : url;
        const args = length !== undefined ? { length } : null;

        this.open(file, args);
      },
      onError: err => {
        this.l10n.get("loading_error").then(msg => {
          this._documentError(msg, err);
        });
      },
      onProgress: (loaded, total) => {
        this.progress(loaded / total);
      },
    });
  },

  setTitleUsingUrl(url = "", downloadUrl = null) {
    this.url = url;
    this.baseUrl = url.split("#")[0];
    if (downloadUrl) {
      this._downloadUrl =
        downloadUrl === url ? this.baseUrl : downloadUrl.split("#")[0];
    }
    let title = getPdfFilenameFromUrl(url, "");
    if (!title) {
      try {
        title = decodeURIComponent(getFilenameFromUrl(url)) || url;
      } catch (ex) {
        // decodeURIComponent may throw URIError,
        // fall back to using the unprocessed url in that case
        title = url;
      }
    }
    this.setTitle(title);
  },

  setTitle(title = this._title) {
    this._title = title;

    if (this.isViewerEmbedded) {
      // Embedded PDF viewers should not be changing their parent page's title.
      return;
    }
    const editorIndicator =
      this._hasAnnotationEditors && !this.pdfRenderingQueue.printing;
    document.title = `${editorIndicator ? "* " : ""}${title}`;
  },

  get _docFilename() {
    // Use `this.url` instead of `this.baseUrl` to perform filename detection
    // based on the reference fragment as ultimate fallback if needed.
    return this._contentDispositionFilename || getPdfFilenameFromUrl(this.url);
  },

  /**
   * @private
   */
  _hideViewBookmark() {
    // URL does not reflect proper document location - hiding some buttons.
    this.appConfig.secondaryToolbar.viewBookmarkButton.hidden = true;
  },

  /**
   * Closes opened PDF document.
   * @returns {Promise} - Returns the promise, which is resolved when all
   *                      destruction is completed.
   */
  async close() {
    this._unblockDocumentLoadEvent();
    this._hideViewBookmark();

    if (!this.pdfLoadingTask) {
      return;
    }
    if (
      (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) &&
      this.pdfDocument?.annotationStorage.size > 0 &&
      this._annotationStorageModified
    ) {
      try {
        // Trigger saving, to prevent data loss in forms; see issue 12257.
        await this.save();
      } catch (reason) {
        // Ignoring errors, to ensure that document closing won't break.
      }
    }
    const promises = [];

    promises.push(this.pdfLoadingTask.destroy());
    this.pdfLoadingTask = null;

    if (this.pdfDocument) {
      this.pdfDocument = null;

      this.pdfThumbnailViewer.setDocument(null);
      this.pdfViewer.setDocument(null);
      this.pdfLinkService.setDocument(null);
      this.pdfDocumentProperties.setDocument(null);
    }
    this.pdfLinkService.externalLinkEnabled = true;
    this.store = null;
    this.isInitialViewSet = false;
    this.downloadComplete = false;
    this.url = "";
    this.baseUrl = "";
    this._downloadUrl = "";
    this.documentInfo = null;
    this.metadata = null;
    this._contentDispositionFilename = null;
    this._contentLength = null;
    this._saveInProgress = false;
    this._docStats = null;
    this._hasAnnotationEditors = false;

    promises.push(this.pdfScriptingManager.destroyPromise);

    this.setTitle();
    this.pdfSidebar.reset();
    this.pdfOutlineViewer.reset();
    this.pdfAttachmentViewer.reset();
    this.pdfLayerViewer.reset();

    this.pdfHistory?.reset();
    this.findBar?.reset();
    this.toolbar.reset();
    this.secondaryToolbar.reset();
    this._PDFBug?.cleanup();

    await Promise.all(promises);
  },

  /**
   * Opens PDF document specified by URL or array with additional arguments.
   * @param {string|TypedArray|ArrayBuffer} file - PDF location or binary data.
   * @param {Object} [args] - Additional arguments for the getDocument call,
   *                          e.g. HTTP headers ('httpHeaders') or alternative
   *                          data transport ('range').
   * @returns {Promise} - Returns the promise, which is resolved when document
   *                      is opened.
   */
  async open(file, args) {
    if (this.pdfLoadingTask) {
      // We need to destroy already opened document.
      await this.close();
    }
    // Set the necessary global worker parameters, using the available options.
    const workerParameters = AppOptions.getAll(OptionKind.WORKER);
    for (const key in workerParameters) {
      GlobalWorkerOptions[key] = workerParameters[key];
    }

    const parameters = Object.create(null);
    if (typeof file === "string") {
      // URL
      this.setTitleUsingUrl(file, /* downloadUrl = */ file);
      parameters.url = file;
    } else if (file && "byteLength" in file) {
      // ArrayBuffer
      parameters.data = file;
    } else if (file.url && file.originalUrl) {
      this.setTitleUsingUrl(file.originalUrl, /* downloadUrl = */ file.url);
      parameters.url = file.url;
    }
    // Set the necessary API parameters, using the available options.
    const apiParameters = AppOptions.getAll(OptionKind.API);
    for (const key in apiParameters) {
      let value = apiParameters[key];

      if (key === "docBaseUrl" && !value) {
        if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("PRODUCTION")) {
          value = document.URL.split("#")[0];
        } else if (PDFJSDev.test("MOZCENTRAL || CHROME")) {
          value = this.baseUrl;
        }
      }
      parameters[key] = value;
    }
    // Finally, update the API parameters with the arguments (if they exist).
    if (args) {
      for (const key in args) {
        parameters[key] = args[key];
      }
    }

    const loadingTask = getDocument(parameters);
    this.pdfLoadingTask = loadingTask;

    loadingTask.onPassword = (updateCallback, reason) => {
      this.pdfLinkService.externalLinkEnabled = false;
      this.passwordPrompt.setUpdateCallback(updateCallback, reason);
      this.passwordPrompt.open();
    };

    loadingTask.onProgress = ({ loaded, total }) => {
      this.progress(loaded / total);
    };

    // Listen for unsupported features to report telemetry.
    loadingTask.onUnsupportedFeature = this.fallback.bind(this);

    return loadingTask.promise.then(
      pdfDocument => {
        this.load(pdfDocument);
      },
      reason => {
        if (loadingTask !== this.pdfLoadingTask) {
          return undefined; // Ignore errors for previously opened PDF files.
        }

        let key = "loading_error";
        if (reason instanceof InvalidPDFException) {
          key = "invalid_file_error";
        } else if (reason instanceof MissingPDFException) {
          key = "missing_file_error";
        } else if (reason instanceof UnexpectedResponseException) {
          key = "unexpected_response_error";
        }
        return this.l10n.get(key).then(msg => {
          this._documentError(msg, { message: reason?.message });
          throw reason;
        });
      }
    );
  },

  /**
   * @private
   */
  _ensureDownloadComplete() {
    if (this.pdfDocument && this.downloadComplete) {
      return;
    }
    throw new Error("PDF document not downloaded.");
  },

  async download() {
    const url = this._downloadUrl,
      filename = this._docFilename;
    try {
      this._ensureDownloadComplete();

      const data = await this.pdfDocument.getData();
      const blob = new Blob([data], { type: "application/pdf" });

      await this.downloadManager.download(blob, url, filename);
    } catch (reason) {
      // When the PDF document isn't ready, or the PDF file is still
      // downloading, simply download using the URL.
      await this.downloadManager.downloadUrl(url, filename);
    }
  },

  async save() {
    if (this._saveInProgress) {
      return;
    }
    this._saveInProgress = true;
    await this.pdfScriptingManager.dispatchWillSave();

    const url = this._downloadUrl,
      filename = this._docFilename;
    try {
      this._ensureDownloadComplete();

      const data = await this.pdfDocument.saveDocument();
      const blob = new Blob([data], { type: "application/pdf" });

      await this.downloadManager.download(blob, url, filename);
    } catch (reason) {
      // When the PDF document isn't ready, or the PDF file is still
      // downloading, simply fallback to a "regular" download.
      console.error(`Error when saving the document: ${reason.message}`);
      await this.download();
    } finally {
      await this.pdfScriptingManager.dispatchDidSave();
      this._saveInProgress = false;
    }

    if (this._hasAnnotationEditors) {
      this.externalServices.reportTelemetry({
        type: "editing",
        data: { type: "save" },
      });
    }
  },

  downloadOrSave() {
    if (this.pdfDocument?.annotationStorage.size > 0) {
      this.save();
    } else {
      this.download();
    }
  },

  fallback(featureId) {
    this.externalServices.reportTelemetry({
      type: "unsupportedFeature",
      featureId,
    });
  },

  /**
   * Report the error; used for errors affecting loading and/or parsing of
   * the entire PDF document.
   */
  _documentError(message, moreInfo = null) {
    this._unblockDocumentLoadEvent();

    this._otherError(message, moreInfo);

    this.eventBus.dispatch("documenterror", {
      source: this,
      message,
      reason: moreInfo?.message ?? null,
    });
  },

  /**
   * Report the error; used for errors affecting e.g. only a single page.
   * @param {string} message - A message that is human readable.
   * @param {Object} [moreInfo] - Further information about the error that is
   *                              more technical. Should have a 'message' and
   *                              optionally a 'stack' property.
   */
  _otherError(message, moreInfo = null) {
    const moreInfoText = [`PDF.js v${version || "?"} (build: ${build || "?"})`];
    if (moreInfo) {
      moreInfoText.push(`Message: ${moreInfo.message}`);

      if (moreInfo.stack) {
        moreInfoText.push(`Stack: ${moreInfo.stack}`);
      } else {
        if (moreInfo.filename) {
          moreInfoText.push(`File: ${moreInfo.filename}`);
        }
        if (moreInfo.lineNumber) {
          moreInfoText.push(`Line: ${moreInfo.lineNumber}`);
        }
      }
    }

    console.error(`${message}\n\n${moreInfoText.join("\n")}`);
    this.fallback();
  },

  progress(level) {
    if (this.downloadComplete) {
      // Don't accidentally show the loading bar again when the entire file has
      // already been fetched (only an issue when disableAutoFetch is enabled).
      return;
    }
    const percent = Math.round(level * 100);
    // When we transition from full request to range requests, it's possible
    // that we discard some of the loaded data. This can cause the loading
    // bar to move backwards. So prevent this by only updating the bar if it
    // increases.
    if (percent <= this.loadingBar.percent) {
      return;
    }
    this.loadingBar.percent = percent;

    // When disableAutoFetch is enabled, it's not uncommon for the entire file
    // to never be fetched (depends on e.g. the file structure). In this case
    // the loading bar will not be completely filled, nor will it be hidden.
    // To prevent displaying a partially filled loading bar permanently, we
    // hide it when no data has been loaded during a certain amount of time.
    const disableAutoFetch =
      this.pdfDocument?.loadingParams.disableAutoFetch ??
      AppOptions.get("disableAutoFetch");

    if (!disableAutoFetch || isNaN(percent)) {
      return;
    }
    if (this.disableAutoFetchLoadingBarTimeout) {
      clearTimeout(this.disableAutoFetchLoadingBarTimeout);
      this.disableAutoFetchLoadingBarTimeout = null;
    }
    this.loadingBar.show();

    this.disableAutoFetchLoadingBarTimeout = setTimeout(() => {
      this.loadingBar.hide();
      this.disableAutoFetchLoadingBarTimeout = null;
    }, DISABLE_AUTO_FETCH_LOADING_BAR_TIMEOUT);
  },

  load(pdfDocument) {
    this.pdfDocument = pdfDocument;

    pdfDocument.getDownloadInfo().then(({ length }) => {
      this._contentLength = length; // Ensure that the correct length is used.
      this.downloadComplete = true;
      this.loadingBar.hide();

      firstPagePromise.then(() => {
        this.eventBus.dispatch("documentloaded", { source: this });
      });
    });

    // Since the `setInitialView` call below depends on this being resolved,
    // fetch it early to avoid delaying initial rendering of the PDF document.
    const pageLayoutPromise = pdfDocument.getPageLayout().catch(function () {
      /* Avoid breaking initial rendering; ignoring errors. */
    });
    const pageModePromise = pdfDocument.getPageMode().catch(function () {
      /* Avoid breaking initial rendering; ignoring errors. */
    });
    const openActionPromise = pdfDocument.getOpenAction().catch(function () {
      /* Avoid breaking initial rendering; ignoring errors. */
    });

    this.toolbar.setPagesCount(pdfDocument.numPages, false);
    this.secondaryToolbar.setPagesCount(pdfDocument.numPages);

    let baseDocumentUrl;
    if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
      baseDocumentUrl = null;
    } else if (PDFJSDev.test("MOZCENTRAL")) {
      baseDocumentUrl = this.baseUrl;
    } else if (PDFJSDev.test("CHROME")) {
      baseDocumentUrl = location.href.split("#")[0];
    }
    this.pdfLinkService.setDocument(pdfDocument, baseDocumentUrl);
    this.pdfDocumentProperties.setDocument(pdfDocument);

    const pdfViewer = this.pdfViewer;
    pdfViewer.setDocument(pdfDocument);
    const { firstPagePromise, onePageRendered, pagesPromise } = pdfViewer;

    const pdfThumbnailViewer = this.pdfThumbnailViewer;
    pdfThumbnailViewer.setDocument(pdfDocument);

    const storedPromise = (this.store = new ViewHistory(
      pdfDocument.fingerprints[0]
    ))
      .getMultiple({
        page: null,
        zoom: DEFAULT_SCALE_VALUE,
        scrollLeft: "0",
        scrollTop: "0",
        rotation: null,
        sidebarView: SidebarView.UNKNOWN,
        scrollMode: ScrollMode.UNKNOWN,
        spreadMode: SpreadMode.UNKNOWN,
      })
      .catch(() => {
        /* Unable to read from storage; ignoring errors. */
        return Object.create(null);
      });

    firstPagePromise.then(pdfPage => {
      this.loadingBar.setWidth(this.appConfig.viewerContainer);
      this._initializeAnnotationStorageCallbacks(pdfDocument);

      Promise.all([
        animationStarted,
        storedPromise,
        pageLayoutPromise,
        pageModePromise,
        openActionPromise,
      ])
        .then(async ([timeStamp, stored, pageLayout, pageMode, openAction]) => {
          const viewOnLoad = AppOptions.get("viewOnLoad");

          this._initializePdfHistory({
            fingerprint: pdfDocument.fingerprints[0],
            viewOnLoad,
            initialDest: openAction?.dest,
          });
          const initialBookmark = this.initialBookmark;

          // Initialize the default values, from user preferences.
          const zoom = AppOptions.get("defaultZoomValue");
          let hash = zoom ? `zoom=${zoom}` : null;

          let rotation = null;
          let sidebarView = AppOptions.get("sidebarViewOnLoad");
          let scrollMode = AppOptions.get("scrollModeOnLoad");
          let spreadMode = AppOptions.get("spreadModeOnLoad");

          if (stored.page && viewOnLoad !== ViewOnLoad.INITIAL) {
            hash =
              `page=${stored.page}&zoom=${zoom || stored.zoom},` +
              `${stored.scrollLeft},${stored.scrollTop}`;

            rotation = parseInt(stored.rotation, 10);
            // Always let user preference take precedence over the view history.
            if (sidebarView === SidebarView.UNKNOWN) {
              sidebarView = stored.sidebarView | 0;
            }
            if (scrollMode === ScrollMode.UNKNOWN) {
              scrollMode = stored.scrollMode | 0;
            }
            if (spreadMode === SpreadMode.UNKNOWN) {
              spreadMode = stored.spreadMode | 0;
            }
          }
          // Always let the user preference/view history take precedence.
          if (pageMode && sidebarView === SidebarView.UNKNOWN) {
            sidebarView = apiPageModeToSidebarView(pageMode);
          }
          if (
            pageLayout &&
            scrollMode === ScrollMode.UNKNOWN &&
            spreadMode === SpreadMode.UNKNOWN
          ) {
            const modes = apiPageLayoutToViewerModes(pageLayout);
            // TODO: Try to improve page-switching when using the mouse-wheel
            // and/or arrow-keys before allowing the document to control this.
            // scrollMode = modes.scrollMode;
            spreadMode = modes.spreadMode;
          }

          this.setInitialView(hash, {
            rotation,
            sidebarView,
            scrollMode,
            spreadMode,
          });
          this.eventBus.dispatch("documentinit", { source: this });
          // Make all navigation keys work on document load,
          // unless the viewer is embedded in a web page.
          if (!this.isViewerEmbedded) {
            pdfViewer.focus();
          }

          // For documents with different page sizes, once all pages are
          // resolved, ensure that the correct location becomes visible on load.
          // (To reduce the risk, in very large and/or slow loading documents,
          //  that the location changes *after* the user has started interacting
          //  with the viewer, wait for either `pagesPromise` or a timeout.)
          await Promise.race([
            pagesPromise,
            new Promise(resolve => {
              setTimeout(resolve, FORCE_PAGES_LOADED_TIMEOUT);
            }),
          ]);
          if (!initialBookmark && !hash) {
            return;
          }
          if (pdfViewer.hasEqualPageSizes) {
            return;
          }
          this.initialBookmark = initialBookmark;

          // eslint-disable-next-line no-self-assign
          pdfViewer.currentScaleValue = pdfViewer.currentScaleValue;
          // Re-apply the initial document location.
          this.setInitialView(hash);
        })
        .catch(() => {
          // Ensure that the document is always completely initialized,
          // even if there are any errors thrown above.
          this.setInitialView();
        })
        .then(function () {
          // At this point, rendering of the initial page(s) should always have
          // started (and may even have completed).
          // To prevent any future issues, e.g. the document being completely
          // blank on load, always trigger rendering here.
          pdfViewer.update();
        });
    });

    pagesPromise.then(
      () => {
        this._unblockDocumentLoadEvent();

        this._initializeAutoPrint(pdfDocument, openActionPromise);
      },
      reason => {
        this.l10n.get("loading_error").then(msg => {
          this._documentError(msg, { message: reason?.message });
        });
      }
    );

    onePageRendered.then(data => {
      this.externalServices.reportTelemetry({
        type: "pageInfo",
        timestamp: data.timestamp,
      });

      pdfDocument.getOutline().then(outline => {
        if (pdfDocument !== this.pdfDocument) {
          return; // The document was closed while the outline resolved.
        }
        this.pdfOutlineViewer.render({ outline, pdfDocument });
      });
      pdfDocument.getAttachments().then(attachments => {
        if (pdfDocument !== this.pdfDocument) {
          return; // The document was closed while the attachments resolved.
        }
        this.pdfAttachmentViewer.render({ attachments });
      });
      // Ensure that the layers accurately reflects the current state in the
      // viewer itself, rather than the default state provided by the API.
      pdfViewer.optionalContentConfigPromise.then(optionalContentConfig => {
        if (pdfDocument !== this.pdfDocument) {
          return; // The document was closed while the layers resolved.
        }
        this.pdfLayerViewer.render({ optionalContentConfig, pdfDocument });
      });
    });

    this._initializePageLabels(pdfDocument);
    this._initializeMetadata(pdfDocument);
  },

  /**
   * @private
   */
  async _scriptingDocProperties(pdfDocument) {
    if (!this.documentInfo) {
      // It should be *extremely* rare for metadata to not have been resolved
      // when this code runs, but ensure that we handle that case here.
      await new Promise(resolve => {
        this.eventBus._on("metadataloaded", resolve, { once: true });
      });
      if (pdfDocument !== this.pdfDocument) {
        return null; // The document was closed while the metadata resolved.
      }
    }
    if (!this._contentLength) {
      // Always waiting for the entire PDF document to be loaded will, most
      // likely, delay sandbox-creation too much in the general case for all
      // PDF documents which are not provided as binary data to the API.
      // Hence we'll simply have to trust that the `contentLength` (as provided
      // by the server), when it exists, is accurate enough here.
      await new Promise(resolve => {
        this.eventBus._on("documentloaded", resolve, { once: true });
      });
      if (pdfDocument !== this.pdfDocument) {
        return null; // The document was closed while the downloadInfo resolved.
      }
    }

    return {
      ...this.documentInfo,
      baseURL: this.baseUrl,
      filesize: this._contentLength,
      filename: this._docFilename,
      metadata: this.metadata?.getRaw(),
      authors: this.metadata?.get("dc:creator"),
      numPages: this.pagesCount,
      URL: this.url,
    };
  },

  /**
   * @private
   */
  async _initializeAutoPrint(pdfDocument, openActionPromise) {
    const [openAction, javaScript] = await Promise.all([
      openActionPromise,
      !this.pdfViewer.enableScripting ? pdfDocument.getJavaScript() : null,
    ]);

    if (pdfDocument !== this.pdfDocument) {
      return; // The document was closed while the auto print data resolved.
    }
    let triggerAutoPrint = false;

    if (openAction?.action === "Print") {
      triggerAutoPrint = true;
    }
    if (javaScript) {
      javaScript.some(js => {
        if (!js) {
          // Don't warn/fallback for empty JavaScript actions.
          return false;
        }
        console.warn("Warning: JavaScript support is not enabled");
        this.fallback(UNSUPPORTED_FEATURES.javaScript);
        return true;
      });

      if (!triggerAutoPrint) {
        // Hack to support auto printing.
        for (const js of javaScript) {
          if (js && AutoPrintRegExp.test(js)) {
            triggerAutoPrint = true;
            break;
          }
        }
      }
    }

    if (triggerAutoPrint) {
      this.triggerPrinting();
    }
  },

  /**
   * @private
   */
  async _initializeMetadata(pdfDocument) {
    const { info, metadata, contentDispositionFilename, contentLength } =
      await pdfDocument.getMetadata();

    if (pdfDocument !== this.pdfDocument) {
      return; // The document was closed while the metadata resolved.
    }
    this.documentInfo = info;
    this.metadata = metadata;
    this._contentDispositionFilename ??= contentDispositionFilename;
    this._contentLength ??= contentLength; // See `getDownloadInfo`-call above.

    // Provides some basic debug information
    console.log(
      `PDF ${pdfDocument.fingerprints[0]} [${info.PDFFormatVersion} ` +
        `${(info.Producer || "-").trim()} / ${(info.Creator || "-").trim()}] ` +
        `(PDF.js: ${version || "?"} [${build || "?"}])`
    );
    let pdfTitle = info.Title;

    const metadataTitle = metadata?.get("dc:title");
    if (metadataTitle) {
      // Ghostscript can produce invalid 'dc:title' Metadata entries:
      //  - The title may be "Untitled" (fixes bug 1031612).
      //  - The title may contain incorrectly encoded characters, which thus
      //    looks broken, hence we ignore the Metadata entry when it contains
      //    characters from the Specials Unicode block (fixes bug 1605526).
      if (
        metadataTitle !== "Untitled" &&
        !/[\uFFF0-\uFFFF]/g.test(metadataTitle)
      ) {
        pdfTitle = metadataTitle;
      }
    }
    if (pdfTitle) {
      this.setTitle(
        `${pdfTitle} - ${this._contentDispositionFilename || this._title}`
      );
    } else if (this._contentDispositionFilename) {
      this.setTitle(this._contentDispositionFilename);
    }

    if (
      info.IsXFAPresent &&
      !info.IsAcroFormPresent &&
      !pdfDocument.isPureXfa
    ) {
      if (pdfDocument.loadingParams.enableXfa) {
        console.warn("Warning: XFA Foreground documents are not supported");
      } else {
        console.warn("Warning: XFA support is not enabled");
      }
      this.fallback(UNSUPPORTED_FEATURES.forms);
    } else if (
      (info.IsAcroFormPresent || info.IsXFAPresent) &&
      !this.pdfViewer.renderForms
    ) {
      console.warn("Warning: Interactive form support is not enabled");
      this.fallback(UNSUPPORTED_FEATURES.forms);
    }

    if (info.IsSignaturesPresent) {
      console.warn("Warning: Digital signatures validation is not supported");
      this.fallback(UNSUPPORTED_FEATURES.signatures);
    }

    // Telemetry labels must be C++ variable friendly.
    let versionId = "other";
    if (KNOWN_VERSIONS.includes(info.PDFFormatVersion)) {
      versionId = `v${info.PDFFormatVersion.replace(".", "_")}`;
    }
    let generatorId = "other";
    if (info.Producer) {
      const producer = info.Producer.toLowerCase();
      KNOWN_GENERATORS.some(function (generator) {
        if (!producer.includes(generator)) {
          return false;
        }
        generatorId = generator.replace(/[ .-]/g, "_");
        return true;
      });
    }
    let formType = null;
    if (info.IsXFAPresent) {
      formType = "xfa";
    } else if (info.IsAcroFormPresent) {
      formType = "acroform";
    }
    this.externalServices.reportTelemetry({
      type: "documentInfo",
      version: versionId,
      generator: generatorId,
      formType,
    });

    this.eventBus.dispatch("metadataloaded", { source: this });
  },

  /**
   * @private
   */
  async _initializePageLabels(pdfDocument) {
    const labels = await pdfDocument.getPageLabels();

    if (pdfDocument !== this.pdfDocument) {
      return; // The document was closed while the page labels resolved.
    }
    if (!labels || AppOptions.get("disablePageLabels")) {
      return;
    }
    const numLabels = labels.length;
    // Ignore page labels that correspond to standard page numbering,
    // or page labels that are all empty.
    let standardLabels = 0,
      emptyLabels = 0;
    for (let i = 0; i < numLabels; i++) {
      const label = labels[i];
      if (label === (i + 1).toString()) {
        standardLabels++;
      } else if (label === "") {
        emptyLabels++;
      } else {
        break;
      }
    }
    if (standardLabels >= numLabels || emptyLabels >= numLabels) {
      return;
    }
    const { pdfViewer, pdfThumbnailViewer, toolbar } = this;

    pdfViewer.setPageLabels(labels);
    pdfThumbnailViewer.setPageLabels(labels);

    // Changing toolbar page display to use labels and we need to set
    // the label of the current page.
    toolbar.setPagesCount(numLabels, true);
    toolbar.setPageNumber(
      pdfViewer.currentPageNumber,
      pdfViewer.currentPageLabel
    );
  },

  /**
   * @private
   */
  _initializePdfHistory({ fingerprint, viewOnLoad, initialDest = null }) {
    if (!this.pdfHistory) {
      return;
    }
    this.pdfHistory.initialize({
      fingerprint,
      resetHistory: viewOnLoad === ViewOnLoad.INITIAL,
      updateUrl: AppOptions.get("historyUpdateUrl"),
    });

    if (this.pdfHistory.initialBookmark) {
      this.initialBookmark = this.pdfHistory.initialBookmark;

      this.initialRotation = this.pdfHistory.initialRotation;
    }

    // Always let the browser history/document hash take precedence.
    if (
      initialDest &&
      !this.initialBookmark &&
      viewOnLoad === ViewOnLoad.UNKNOWN
    ) {
      this.initialBookmark = JSON.stringify(initialDest);
      // TODO: Re-factor the `PDFHistory` initialization to remove this hack
      // that's currently necessary to prevent weird initial history state.