pdf.js/web/pdf_page_view.js

/* 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.
 */

// eslint-disable-next-line max-len
/** @typedef {import("../src/display/display_utils").PageViewport} PageViewport */
// eslint-disable-next-line max-len
/** @typedef {import("../src/display/optional_content_config").OptionalContentConfig} OptionalContentConfig */
/** @typedef {import("./event_utils").EventBus} EventBus */
/** @typedef {import("./interfaces").IL10n} IL10n */
/** @typedef {import("./interfaces").IRenderableView} IRenderableView */
// eslint-disable-next-line max-len
/** @typedef {import("./pdf_rendering_queue").PDFRenderingQueue} PDFRenderingQueue */

import {
  AbortException,
  AnnotationMode,
  createPromiseCapability,
  PixelsPerInch,
  RenderingCancelledException,
  setLayerDimensions,
  shadow,
  SVGGraphics,
} from "pdfjs-lib";
import {
  approximateFraction,
  DEFAULT_SCALE,
  docStyle,
  OutputScale,
  RendererType,
  RenderingStates,
  roundToDivide,
  TextLayerMode,
} from "./ui_utils.js";
import { AnnotationEditorLayerBuilder } from "./annotation_editor_layer_builder.js";
import { AnnotationLayerBuilder } from "./annotation_layer_builder.js";
import { compatibilityParams } from "./app_options.js";
import { NullL10n } from "./l10n_utils.js";
import { StructTreeLayerBuilder } from "./struct_tree_layer_builder.js";
import { TextAccessibilityManager } from "./text_accessibility.js";
import { TextHighlighter } from "./text_highlighter.js";
import { TextLayerBuilder } from "./text_layer_builder.js";
import { XfaLayerBuilder } from "./xfa_layer_builder.js";

/**
 * @typedef {Object} PDFPageViewOptions
 * @property {HTMLDivElement} [container] - The viewer element.
 * @property {EventBus} eventBus - The application event bus.
 * @property {number} id - The page unique ID (normally its number).
 * @property {number} [scale] - The page scale display.
 * @property {PageViewport} defaultViewport - The page viewport.
 * @property {Promise<OptionalContentConfig>} [optionalContentConfigPromise] -
 *   A promise that is resolved with an {@link OptionalContentConfig} instance.
 *   The default value is `null`.
 * @property {PDFRenderingQueue} [renderingQueue] - The rendering queue object.
 * @property {number} [textLayerMode] - Controls if the text layer used for
 *   selection and searching is created. The constants from {TextLayerMode}
 *   should be used. The default value is `TextLayerMode.ENABLE`.
 * @property {number} [annotationMode] - Controls if the annotation layer is
 *   created, and if interactive form elements or `AnnotationStorage`-data are
 *   being rendered. The constants from {@link AnnotationMode} should be used;
 *   see also {@link RenderParameters} and {@link GetOperatorListParameters}.
 *   The default value is `AnnotationMode.ENABLE_FORMS`.
 * @property {string} [imageResourcesPath] - Path for image resources, mainly
 *   for annotation icons. Include trailing slash.
 * @property {boolean} [useOnlyCssZoom] - Enables CSS only zooming. The default
 *   value is `false`.
 * @property {boolean} [isOffscreenCanvasSupported] - Allows to use an
 *   OffscreenCanvas if needed.
 * @property {number} [maxCanvasPixels] - The maximum supported canvas size in
 *   total pixels, i.e. width * height. Use -1 for no limit. The default value
 *   is 4096 * 4096 (16 mega-pixels).
 * @property {Object} [pageColors] - Overwrites background and foreground colors
 *   with user defined ones in order to improve readability in high contrast
 *   mode.
 * @property {IL10n} [l10n] - Localization service.
 * @property {function} [layerProperties] - The function that is used to lookup
 *   the necessary layer-properties.
 */

const MAX_CANVAS_PIXELS = compatibilityParams.maxCanvasPixels || 16777216;

const DEFAULT_LAYER_PROPERTIES = () => {
  if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("COMPONENTS")) {
    return null;
  }
  return {
    annotationEditorUIManager: null,
    annotationStorage: null,
    downloadManager: null,
    enableScripting: false,
    fieldObjectsPromise: null,
    findController: null,
    hasJSActionsPromise: null,
    get linkService() {
      const { SimpleLinkService } = require("./pdf_link_service.js");
      return new SimpleLinkService();
    },
  };
};

/**
 * @implements {IRenderableView}
 */
class PDFPageView {
  #annotationMode = AnnotationMode.ENABLE_FORMS;

  #layerProperties = null;

  #previousRotation = null;

  #useThumbnailCanvas = {
    initialOptionalContent: true,
    regularAnnotations: true,
  };

  /**
   * @param {PDFPageViewOptions} options
   */
  constructor(options) {
    const container = options.container;
    const defaultViewport = options.defaultViewport;

    this.id = options.id;
    this.renderingId = "page" + this.id;
    this.#layerProperties = options.layerProperties || DEFAULT_LAYER_PROPERTIES;

    this.pdfPage = null;
    this.pageLabel = null;
    this.rotation = 0;
    this.scale = options.scale || DEFAULT_SCALE;
    this.viewport = defaultViewport;
    this.pdfPageRotate = defaultViewport.rotation;
    this._optionalContentConfigPromise =
      options.optionalContentConfigPromise || null;
    this.hasRestrictedScaling = false;
    this.textLayerMode = options.textLayerMode ?? TextLayerMode.ENABLE;
    this.#annotationMode =
      options.annotationMode ?? AnnotationMode.ENABLE_FORMS;
    this.imageResourcesPath = options.imageResourcesPath || "";
    this.useOnlyCssZoom = options.useOnlyCssZoom || false;
    this.isOffscreenCanvasSupported =
      options.isOffscreenCanvasSupported ?? true;
    this.maxCanvasPixels = options.maxCanvasPixels || MAX_CANVAS_PIXELS;
    this.pageColors = options.pageColors || null;

    this.eventBus = options.eventBus;
    this.renderingQueue = options.renderingQueue;
    if (
      typeof PDFJSDev === "undefined" ||
      PDFJSDev.test("!PRODUCTION || GENERIC")
    ) {
      this.renderer = options.renderer || RendererType.CANVAS;
    }
    this.l10n = options.l10n || NullL10n;

    this.paintTask = null;
    this.paintedViewportMap = new WeakMap();
    this.renderingState = RenderingStates.INITIAL;
    this.resume = null;
    this._renderError = null;
    if (
      typeof PDFJSDev === "undefined" ||
      PDFJSDev.test("!PRODUCTION || GENERIC")
    ) {
      this._isStandalone = !this.renderingQueue?.hasViewer();
    }

    this._annotationCanvasMap = null;

    this.annotationLayer = null;
    this.annotationEditorLayer = null;
    this.textLayer = null;
    this.zoomLayer = null;
    this.xfaLayer = null;
    this.structTreeLayer = null;

    const div = document.createElement("div");
    div.className = "page";
    div.setAttribute("data-page-number", this.id);
    div.setAttribute("role", "region");
    this.l10n.get("page_landmark", { page: this.id }).then(msg => {
      div.setAttribute("aria-label", msg);
    });
    this.div = div;

    this.#setDimensions();

    container?.append(div);

    if (
      (typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")) &&
      this._isStandalone
    ) {
      // Ensure that the various layers always get the correct initial size,
      // see issue 15795.
      docStyle.setProperty(
        "--scale-factor",
        this.scale * PixelsPerInch.PDF_TO_CSS_UNITS
      );

      const { optionalContentConfigPromise } = options;
      if (optionalContentConfigPromise) {
        // Ensure that the thumbnails always display the *initial* document
        // state, for documents with optional content.
        optionalContentConfigPromise.then(optionalContentConfig => {
          if (
            optionalContentConfigPromise !== this._optionalContentConfigPromise
          ) {
            return;
          }
          this.#useThumbnailCanvas.initialOptionalContent =
            optionalContentConfig.hasInitialVisibility;
        });
      }
    }
  }

  #setDimensions() {
    const { viewport } = this;
    if (this.#previousRotation === viewport.rotation) {
      return;
    }
    this.#previousRotation = viewport.rotation;

    setLayerDimensions(
      this.div,
      viewport,
      /* mustFlip = */ true,
      /* mustRotate = */ false
    );
  }

  setPdfPage(pdfPage) {
    this.pdfPage = pdfPage;
    this.pdfPageRotate = pdfPage.rotate;

    const totalRotation = (this.rotation + this.pdfPageRotate) % 360;
    this.viewport = pdfPage.getViewport({
      scale: this.scale * PixelsPerInch.PDF_TO_CSS_UNITS,
      rotation: totalRotation,
    });
    this.#setDimensions();
    this.reset();
  }

  destroy() {
    this.reset();
    this.pdfPage?.cleanup();
  }

  get _textHighlighter() {
    return shadow(
      this,
      "_textHighlighter",
      new TextHighlighter({
        pageIndex: this.id - 1,
        eventBus: this.eventBus,
        findController: this.#layerProperties().findController,
      })
    );
  }

  async #renderAnnotationLayer() {
    let error = null;
    try {
      await this.annotationLayer.render(this.viewport, "display");
    } catch (ex) {
      console.error(`#renderAnnotationLayer: "${ex}".`);
      error = ex;
    } finally {
      this.eventBus.dispatch("annotationlayerrendered", {
        source: this,
        pageNumber: this.id,
        error,
      });
    }
  }

  async #renderAnnotationEditorLayer() {
    let error = null;
    try {
      await this.annotationEditorLayer.render(this.viewport, "display");
    } catch (ex) {
      console.error(`#renderAnnotationEditorLayer: "${ex}".`);
      error = ex;
    } finally {
      this.eventBus.dispatch("annotationeditorlayerrendered", {
        source: this,
        pageNumber: this.id,
        error,
      });
    }
  }

  async #renderXfaLayer() {
    let error = null;
    try {
      const result = await this.xfaLayer.render(this.viewport, "display");
      if (result?.textDivs && this._textHighlighter) {
        this.#buildXfaTextContentItems(result.textDivs);
      }
    } catch (ex) {
      console.error(`#renderXfaLayer: "${ex}".`);
      error = ex;
    } finally {
      this.eventBus.dispatch("xfalayerrendered", {
        source: this,
        pageNumber: this.id,
        error,
      });
    }
  }

  async #renderTextLayer() {
    const { pdfPage, textLayer, viewport } = this;
    if (!textLayer) {
      return;
    }

    let error = null;
    try {
      if (!textLayer.renderingDone) {
        const readableStream = pdfPage.streamTextContent({
          includeMarkedContent: true,
        });
        textLayer.setTextContentSource(readableStream);
      }
      await textLayer.render(viewport);
    } catch (ex) {
      if (ex instanceof AbortException) {
        return;
      }
      console.error(`#renderTextLayer: "${ex}".`);
      error = ex;
    }

    this.eventBus.dispatch("textlayerrendered", {
      source: this,
      pageNumber: this.id,
      numTextDivs: textLayer.numTextDivs,
      error,
    });

    this.#renderStructTreeLayer();
  }

  /**
   * The structure tree is currently only supported when the text layer is
   * enabled and a canvas is used for rendering.
   *
   * The structure tree must be generated after the text layer for the
   * aria-owns to work.
   */
  async #renderStructTreeLayer() {
    if (!this.textLayer) {
      return;
    }
    this.structTreeLayer ||= new StructTreeLayerBuilder();

    const tree = await (!this.structTreeLayer.renderingDone
      ? this.pdfPage.getStructTree()
      : null);
    const treeDom = this.structTreeLayer?.render(tree);
    if (treeDom) {
      this.canvas?.append(treeDom);
    }
  }

  async #buildXfaTextContentItems(textDivs) {
    const text = await this.pdfPage.getTextContent();
    const items = [];
    for (const item of text.items) {
      items.push(item.str);
    }
    this._textHighlighter.setTextMapping(textDivs, items);
    this._textHighlighter.enable();
  }

  /**
   * @private
   */
  _resetZoomLayer(removeFromDOM = false) {
    if (!this.zoomLayer) {
      return;
    }
    const zoomLayerCanvas = this.zoomLayer.firstChild;
    this.paintedViewportMap.delete(zoomLayerCanvas);
    // Zeroing the width and height causes Firefox to release graphics
    // resources immediately, which can greatly reduce memory consumption.
    zoomLayerCanvas.width = 0;
    zoomLayerCanvas.height = 0;

    if (removeFromDOM) {
      // Note: `ChildNode.remove` doesn't throw if the parent node is undefined.
      this.zoomLayer.remove();
    }
    this.zoomLayer = null;
  }

  reset({
    keepZoomLayer = false,
    keepAnnotationLayer = false,
    keepAnnotationEditorLayer = false,
    keepXfaLayer = false,
    keepTextLayer = false,
  } = {}) {
    this.cancelRendering({
      keepAnnotationLayer,
      keepAnnotationEditorLayer,
      keepXfaLayer,
      keepTextLayer,
    });
    this.renderingState = RenderingStates.INITIAL;

    const div = this.div;

    const childNodes = div.childNodes,
      zoomLayerNode = (keepZoomLayer && this.zoomLayer) || null,
      annotationLayerNode =
        (keepAnnotationLayer && this.annotationLayer?.div) || null,
      annotationEditorLayerNode =
        (keepAnnotationEditorLayer && this.annotationEditorLayer?.div) || null,
      xfaLayerNode = (keepXfaLayer && this.xfaLayer?.div) || null,
      textLayerNode = (keepTextLayer && this.textLayer?.div) || null;
    for (let i = childNodes.length - 1; i >= 0; i--) {
      const node = childNodes[i];
      switch (node) {
        case zoomLayerNode:
        case annotationLayerNode:
        case annotationEditorLayerNode:
        case xfaLayerNode:
        case textLayerNode:
        case this.loadingIconDiv:
          continue;
      }
      node.remove();
    }
    div.removeAttribute("data-loaded");

    if (annotationLayerNode) {
      // Hide the annotation layer until all elements are resized
      // so they are not displayed on the already resized page.
      this.annotationLayer.hide();
    }
    if (annotationEditorLayerNode) {
      this.annotationEditorLayer.hide();
    }
    if (xfaLayerNode) {
      // Hide the XFA layer until all elements are resized
      // so they are not displayed on the already resized page.
      this.xfaLayer.hide();
    }
    if (textLayerNode) {
      this.textLayer.hide();
    }

    if (!zoomLayerNode) {
      if (this.canvas) {
        this.paintedViewportMap.delete(this.canvas);
        // Zeroing the width and height causes Firefox to release graphics
        // resources immediately, which can greatly reduce memory consumption.
        this.canvas.width = 0;
        this.canvas.height = 0;
        delete this.canvas;
      }
      this._resetZoomLayer();
    }
    if (
      (typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")) &&
      this.svg
    ) {
      this.paintedViewportMap.delete(this.svg);
      delete this.svg;
    }

    if (!this.loadingIconDiv) {
      this.loadingIconDiv = document.createElement("div");
      this.loadingIconDiv.className = "loadingIcon notVisible";
      this.loadingIconDiv.setAttribute("role", "img");
      this.l10n.get("loading").then(msg => {
        this.loadingIconDiv?.setAttribute("aria-label", msg);
      });
      div.append(this.loadingIconDiv);
    } else {
      this.toggleLoadingIconSpinner();
      div.append(this.loadingIconDiv);
    }

    if (
      (typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")) &&
      this._isStandalone
    ) {
      this.toggleLoadingIconSpinner(/* viewVisible = */ true);
    }
  }

  update({
    scale = 0,
    rotation = null,
    optionalContentConfigPromise = null,
    drawingDelay = -1,
  }) {
    this.scale = scale || this.scale;
    if (typeof rotation === "number") {
      this.rotation = rotation; // The rotation may be zero.
    }
    if (optionalContentConfigPromise instanceof Promise) {
      this._optionalContentConfigPromise = optionalContentConfigPromise;

      // Ensure that the thumbnails always display the *initial* document state,
      // for documents with optional content.
      optionalContentConfigPromise.then(optionalContentConfig => {
        if (
          optionalContentConfigPromise !== this._optionalContentConfigPromise
        ) {
          return;
        }
        this.#useThumbnailCanvas.initialOptionalContent =
          optionalContentConfig.hasInitialVisibility;
      });
    }

    const totalRotation = (this.rotation + this.pdfPageRotate) % 360;
    this.viewport = this.viewport.clone({
      scale: this.scale * PixelsPerInch.PDF_TO_CSS_UNITS,
      rotation: totalRotation,
    });
    this.#setDimensions();

    if (
      (typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")) &&
      this._isStandalone
    ) {
      docStyle.setProperty("--scale-factor", this.viewport.scale);
    }

    if (
      (typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")) &&
      this.svg
    ) {
      this.cssTransform({
        target: this.svg,
        redrawAnnotationLayer: true,
        redrawAnnotationEditorLayer: true,
        redrawXfaLayer: true,
        redrawTextLayer: true,
      });

      this.eventBus.dispatch("pagerendered", {
        source: this,
        pageNumber: this.id,
        cssTransform: true,
        timestamp: performance.now(),
        error: this._renderError,
      });
      return;
    }

    let isScalingRestricted = false;
    if (this.canvas && this.maxCanvasPixels > 0) {
      const outputScale = this.outputScale;
      if (
        ((Math.floor(this.viewport.width) * outputScale.sx) | 0) *
          ((Math.floor(this.viewport.height) * outputScale.sy) | 0) >
        this.maxCanvasPixels
      ) {
        isScalingRestricted = true;
      }
    }

    const postponeDrawing = drawingDelay >= 0 && drawingDelay < 1000;

    if (this.canvas) {
      if (
        postponeDrawing ||
        this.useOnlyCssZoom ||
        (this.hasRestrictedScaling && isScalingRestricted)
      ) {
        if (
          postponeDrawing &&
          this.renderingState !== RenderingStates.FINISHED
        ) {
          this.cancelRendering({
            keepZoomLayer: true,
            keepAnnotationLayer: true,
            keepAnnotationEditorLayer: true,
            keepXfaLayer: true,
            keepTextLayer: true,
            cancelExtraDelay: drawingDelay,
          });
          // It isn't really finished, but once we have finished
          // to postpone, we'll call this.reset(...) which will set
          // the rendering state to INITIAL, hence the next call to
          // PDFViewer.update() will trigger a redraw (if it's mandatory).
          this.renderingState = RenderingStates.FINISHED;
        }

        this.cssTransform({
          target: this.canvas,
          redrawAnnotationLayer: true,
          redrawAnnotationEditorLayer: true,
          redrawXfaLayer: true,
          redrawTextLayer: !postponeDrawing,
          hideTextLayer: postponeDrawing,
        });

        this.eventBus.dispatch("pagerendered", {
          source: this,
          pageNumber: this.id,
          cssTransform: true,
          timestamp: performance.now(),
          error: this._renderError,
        });
        return;
      }
      if (!this.zoomLayer && !this.canvas.hidden) {
        this.zoomLayer = this.canvas.parentNode;
        this.zoomLayer.style.position = "absolute";
      }
    }
    if (this.zoomLayer) {
      this.cssTransform({ target: this.zoomLayer.firstChild });
    }
    this.reset({
      keepZoomLayer: true,
      keepAnnotationLayer: true,
      keepAnnotationEditorLayer: true,
      keepXfaLayer: true,
      keepTextLayer: true,
    });
  }

  /**
   * PLEASE NOTE: Most likely you want to use the `this.reset()` method,
   *              rather than calling this one directly.
   */
  cancelRendering({
    keepAnnotationLayer = false,
    keepAnnotationEditorLayer = false,
    keepXfaLayer = false,
    keepTextLayer = false,
    cancelExtraDelay = 0,
  } = {}) {
    if (this.paintTask) {
      this.paintTask.cancel(cancelExtraDelay);
      this.paintTask = null;
    }
    this.resume = null;

    if (this.textLayer && (!keepTextLayer || !this.textLayer.div)) {
      this.textLayer.cancel();
      this.textLayer = null;
    }
    if (this.structTreeLayer && !this.textLayer) {
      this.structTreeLayer = null;
    }
    if (
      this.annotationLayer &&
      (!keepAnnotationLayer || !this.annotationLayer.div)
    ) {
      this.annotationLayer.cancel();
      this.annotationLayer = null;
      this._annotationCanvasMap = null;
    }
    if (
      this.annotationEditorLayer &&
      (!keepAnnotationEditorLayer || !this.annotationEditorLayer.div)
    ) {
      this.annotationEditorLayer.cancel();
      this.annotationEditorLayer = null;
    }
    if (this.xfaLayer && (!keepXfaLayer || !this.xfaLayer.div)) {
      this.xfaLayer.cancel();
      this.xfaLayer = null;
      this._textHighlighter?.disable();
    }
  }

  cssTransform({
    target,
    redrawAnnotationLayer = false,
    redrawAnnotationEditorLayer = false,
    redrawXfaLayer = false,
    redrawTextLayer = false,
    hideTextLayer = false,
  }) {
    // Scale target (canvas or svg), its wrapper and page container.

    if (target instanceof HTMLCanvasElement) {
      if (!target.hasAttribute("zooming")) {
        target.setAttribute("zooming", true);
        const { style } = target;
        style.width = style.height = "";
      }
    } else {
      const div = this.div;
      const { width, height } = this.viewport;

      target.style.width =
        target.parentNode.style.width =
        div.style.width =
          Math.floor(width) + "px";
      target.style.height =
        target.parentNode.style.height =
        div.style.height =
          Math.floor(height) + "px";
    }

    const originalViewport = this.paintedViewportMap.get(target);
    if (this.viewport !== originalViewport) {
      // The canvas may have been originally rotated; rotate relative to that.
      const relativeRotation =
        this.viewport.rotation - originalViewport.rotation;
      const absRotation = Math.abs(relativeRotation);
      let scaleX = 1,
        scaleY = 1;
      if (absRotation === 90 || absRotation === 270) {
        const { width, height } = this.viewport;
        // Scale x and y because of the rotation.
        scaleX = height / width;
        scaleY = width / height;
      }

      if (absRotation !== 0) {
        target.style.transform = `rotate(${relativeRotation}deg) scale(${scaleX}, ${scaleY})`;
      }
    }

    if (redrawAnnotationLayer && this.annotationLayer) {
      this.#renderAnnotationLayer();
    }
    if (redrawAnnotationEditorLayer && this.annotationEditorLayer) {
      this.#renderAnnotationEditorLayer();
    }
    if (redrawXfaLayer && this.xfaLayer) {
      this.#renderXfaLayer();
    }

    if (this.textLayer) {
      if (hideTextLayer) {
        this.textLayer.hide();
      } else if (redrawTextLayer) {
        this.#renderTextLayer();
      }
    }
  }

  get width() {
    return this.viewport.width;
  }

  get height() {
    return this.viewport.height;
  }

  getPagePoint(x, y) {
    return this.viewport.convertToPdfPoint(x, y);
  }

  /**
   * @ignore
   */
  toggleLoadingIconSpinner(viewVisible = false) {
    this.loadingIconDiv?.classList.toggle("notVisible", !viewVisible);
  }

  draw() {
    if (this.renderingState !== RenderingStates.INITIAL) {
      console.error("Must be in new state before drawing");
      this.reset(); // Ensure that we reset all state to prevent issues.
    }
    const { div, pdfPage } = this;

    if (!pdfPage) {
      this.renderingState = RenderingStates.FINISHED;

      if (this.loadingIconDiv) {
        this.loadingIconDiv.remove();
        delete this.loadingIconDiv;
      }
      return Promise.reject(new Error("pdfPage is not loaded"));
    }

    this.renderingState = RenderingStates.RUNNING;

    // Wrap the canvas so that if it has a CSS transform for high DPI the
    // overflow will be hidden in Firefox.
    const canvasWrapper = document.createElement("div");
    canvasWrapper.classList.add("canvasWrapper");

    if (this.textLayer) {
      this.textLayer.div.before(canvasWrapper);
    } else {
      const lastDivBeforeTextDiv =
        this.annotationLayer?.div || this.annotationEditorLayer?.div;
      if (lastDivBeforeTextDiv) {
        // The annotation layer needs to stay on top.
        lastDivBeforeTextDiv.before(canvasWrapper);
      } else {
        div.append(canvasWrapper);
      }
    }

    if (
      !this.textLayer &&
      this.textLayerMode !== TextLayerMode.DISABLE &&
      !pdfPage.isPureXfa
    ) {
      this._accessibilityManager ||= new TextAccessibilityManager();

      this.textLayer = new TextLayerBuilder({
        highlighter: this._textHighlighter,
        accessibilityManager: this._accessibilityManager,
        isOffscreenCanvasSupported: this.isOffscreenCanvasSupported,
      });
      canvasWrapper.after(this.textLayer.div);
    }

    if (
      !this.annotationLayer &&
      this.#annotationMode !== AnnotationMode.DISABLE
    ) {
      const {
        annotationStorage,
        downloadManager,
        enableScripting,
        fieldObjectsPromise,
        hasJSActionsPromise,
        linkService,
      } = this.#layerProperties();

      this._annotationCanvasMap ||= new Map();
      this.annotationLayer = new AnnotationLayerBuilder({
        pageDiv: div,
        pdfPage,
        annotationStorage,
        imageResourcesPath: this.imageResourcesPath,
        renderForms: this.#annotationMode === AnnotationMode.ENABLE_FORMS,
        linkService,
        downloadManager,
        l10n: this.l10n,
        enableScripting,
        hasJSActionsPromise,
        fieldObjectsPromise,
        annotationCanvasMap: this._annotationCanvasMap,
        accessibilityManager: this._accessibilityManager,
      });
    }

    if (this.xfaLayer?.div) {
      // The xfa layer needs to stay on top.
      div.append(this.xfaLayer.div);
    }

    let renderContinueCallback = null;
    if (this.renderingQueue) {
      renderContinueCallback = cont => {
        if (!this.renderingQueue.isHighestPriority(this)) {
          this.renderingState = RenderingStates.PAUSED;
          this.resume = () => {
            this.renderingState = RenderingStates.RUNNING;
            cont();
          };
          return;
        }
        cont();
      };
    }

    const finishPaintTask = async (error = null) => {
      // The paintTask may have been replaced by a new one, so only remove
      // the reference to the paintTask if it matches the one that is
      // triggering this callback.
      if (paintTask === this.paintTask) {
        this.paintTask = null;
      }

      if (error instanceof RenderingCancelledException) {
        this._renderError = null;
        return;
      }
      this._renderError = error;

      this.renderingState = RenderingStates.FINISHED;

      if (this.loadingIconDiv) {
        this.loadingIconDiv.remove();
        delete this.loadingIconDiv;
      }
      this._resetZoomLayer(/* removeFromDOM = */ true);

      // Ensure that the thumbnails won't become partially (or fully) blank,
      // for documents that contain interactive form elements.
      this.#useThumbnailCanvas.regularAnnotations = !paintTask.separateAnnots;

      this.eventBus.dispatch("pagerendered", {
        source: this,
        pageNumber: this.id,
        cssTransform: false,
        timestamp: performance.now(),
        error: this._renderError,
      });

      if (error) {
        throw error;
      }
    };

    const paintTask =
      (typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")) &&
      this.renderer === RendererType.SVG
        ? this.paintOnSvg(canvasWrapper)
        : this.paintOnCanvas(canvasWrapper);
    paintTask.onRenderContinue = renderContinueCallback;
    this.paintTask = paintTask;

    const resultPromise = paintTask.promise.then(
      () => {
        return finishPaintTask(null).then(async () => {
          this.#renderTextLayer();

          if (this.annotationLayer) {
            await this.#renderAnnotationLayer();
          }

          if (!this.annotationEditorLayer) {
            const { annotationEditorUIManager } = this.#layerProperties();

            if (!annotationEditorUIManager) {
              return;
            }
            this.annotationEditorLayer = new AnnotationEditorLayerBuilder({
              uiManager: annotationEditorUIManager,
              pageDiv: div,
              pdfPage,
              l10n: this.l10n,
              accessibilityManager: this._accessibilityManager,
            });
          }
          this.#renderAnnotationEditorLayer();
        });
      },
      function (reason) {
        return finishPaintTask(reason);
      }
    );

    if (pdfPage.isPureXfa) {
      if (!this.xfaLayer) {
        const { annotationStorage, linkService } = this.#layerProperties();

        this.xfaLayer = new XfaLayerBuilder({
          pageDiv: div,
          pdfPage,
          annotationStorage,
          linkService,
        });
      }
      this.#renderXfaLayer();
    }

    div.setAttribute("data-loaded", true);

    this.eventBus.dispatch("pagerender", {
      source: this,
      pageNumber: this.id,
    });
    return resultPromise;
  }

  paintOnCanvas(canvasWrapper) {
    const renderCapability = createPromiseCapability();
    const result = {
      promise: renderCapability.promise,
      onRenderContinue(cont) {
        cont();
      },
      cancel(extraDelay = 0) {
        renderTask.cancel(extraDelay);
      },
      get separateAnnots() {
        return renderTask.separateAnnots;
      },
    };

    const viewport = this.viewport;
    const { width, height } = viewport;
    const canvas = document.createElement("canvas");
    canvas.setAttribute("role", "presentation");

    // Keep the canvas hidden until the first draw callback, or until drawing
    // is complete when `!this.renderingQueue`, to prevent black flickering.
    canvas.hidden = true;
    let isCanvasHidden = true;
    const showCanvas = function () {
      if (isCanvasHidden) {
        canvas.hidden = false;
        isCanvasHidden = false;
      }
    };

    canvasWrapper.append(canvas);
    this.canvas = canvas;

    const ctx = canvas.getContext("2d", { alpha: false });
    const outputScale = (this.outputScale = new OutputScale());

    if (this.useOnlyCssZoom) {
      const actualSizeViewport = viewport.clone({
        scale: PixelsPerInch.PDF_TO_CSS_UNITS,
      });
      // Use a scale that makes the canvas have the originally intended size
      // of the page.
      outputScale.sx *= actualSizeViewport.width / width;
      outputScale.sy *= actualSizeViewport.height / height;
    }

    if (this.maxCanvasPixels > 0) {
      const pixelsInViewport = width * height;
      const maxScale = Math.sqrt(this.maxCanvasPixels / pixelsInViewport);
      if (outputScale.sx > maxScale || outputScale.sy > maxScale) {
        outputScale.sx = maxScale;
        outputScale.sy = maxScale;
        this.hasRestrictedScaling = true;
      } else {
        this.hasRestrictedScaling = false;
      }
    }

    const sfx = approximateFraction(outputScale.sx);
    const sfy = approximateFraction(outputScale.sy);

    canvas.width = roundToDivide(viewport.width * outputScale.sx, sfx[0]);
    canvas.height = roundToDivide(viewport.height * outputScale.sy, sfy[0]);
    const { style } = canvas;
    style.width = roundToDivide(viewport.width, sfx[1]) + "px";
    style.height = roundToDivide(viewport.height, sfy[1]) + "px";

    // Add the viewport so it's known what it was originally drawn with.
    this.paintedViewportMap.set(canvas, viewport);

    // Rendering area
    const transform = outputScale.scaled
      ? [outputScale.sx, 0, 0, outputScale.sy, 0, 0]
      : null;
    const renderContext = {
      canvasContext: ctx,
      transform,
      viewport,
      annotationMode: this.#annotationMode,
      optionalContentConfigPromise: this._optionalContentConfigPromise,
      annotationCanvasMap: this._annotationCanvasMap,
      pageColors: this.pageColors,
    };
    const renderTask = this.pdfPage.render(renderContext);
    renderTask.onContinue = function (cont) {
      showCanvas();
      if (result.onRenderContinue) {
        result.onRenderContinue(cont);
      } else {
        cont();
      }
    };

    renderTask.promise.then(
      function () {
        showCanvas();
        renderCapability.resolve();
      },
      function (error) {
        showCanvas();
        renderCapability.reject(error);
      }
    );
    return result;
  }

  paintOnSvg(wrapper) {
    if (
      !(
        typeof PDFJSDev === "undefined" ||
        PDFJSDev.test("!PRODUCTION || GENERIC")
      )
    ) {
      throw new Error("Not implemented: paintOnSvg");
    }
    let cancelled = false;
    const ensureNotCancelled = () => {
      if (cancelled) {
        throw new RenderingCancelledException(
          `Rendering cancelled, page ${this.id}`,
          "svg"
        );
      }
    };

    const pdfPage = this.pdfPage;
    const actualSizeViewport = this.viewport.clone({
      scale: PixelsPerInch.PDF_TO_CSS_UNITS,
    });
    const promise = pdfPage
      .getOperatorList({
        annotationMode: this.#annotationMode,
      })
      .then(opList => {
        ensureNotCancelled();
        const svgGfx = new SVGGraphics(pdfPage.commonObjs, pdfPage.objs);
        return svgGfx.getSVG(opList, actualSizeViewport).then(svg => {
          ensureNotCancelled();
          this.svg = svg;
          this.paintedViewportMap.set(svg, actualSizeViewport);

          svg.style.width = wrapper.style.width;
          svg.style.height = wrapper.style.height;
          this.renderingState = RenderingStates.FINISHED;
          wrapper.append(svg);
        });
      });

    return {
      promise,
      onRenderContinue(cont) {
        cont();
      },
      cancel() {
        cancelled = true;
      },
      get separateAnnots() {
        return false;
      },
    };
  }

  /**
   * @param {string|null} label
   */
  setPageLabel(label) {
    this.pageLabel = typeof label === "string" ? label : null;

    if (this.pageLabel !== null) {
      this.div.setAttribute("data-page-label", this.pageLabel);
    } else {
      this.div.removeAttribute("data-page-label");
    }
  }

  /**
   * For use by the `PDFThumbnailView.setImage`-method.
   * @ignore
   */
  get thumbnailCanvas() {
    const { initialOptionalContent, regularAnnotations } =
      this.#useThumbnailCanvas;
    return initialOptionalContent && regularAnnotations ? this.canvas : null;
  }
}

export { PDFPageView };