import { captureException } from '../../../infrastructure/error-reporter' import { generatePdfCachingTransportFactory } from './pdf-caching-transport' import { debugConsole } from '@/utils/debugging' const params = new URLSearchParams(window.location.search) const disableFontFace = params.get('disable-font-face') === 'true' const disableStream = process.env.NODE_ENV !== 'test' const DEFAULT_RANGE_CHUNK_SIZE = 128 * 1024 // 128K chunks export default class PDFJSWrapper { constructor(container) { this.container = container } async init() { const { PDFJS, PDFJSViewer, cMapUrl, imageResourcesPath, standardFontDataUrl, } = await import('./pdf-js-versions').then(m => { return m.default }) this.PDFJS = PDFJS this.genPdfCachingTransport = generatePdfCachingTransportFactory(PDFJS) this.PDFJSViewer = PDFJSViewer this.cMapUrl = cMapUrl this.standardFontDataUrl = standardFontDataUrl this.imageResourcesPath = imageResourcesPath // create the event bus const eventBus = new PDFJSViewer.EventBus() // create the link service const linkService = new PDFJSViewer.PDFLinkService({ eventBus, externalLinkTarget: 2, externalLinkRel: 'noopener', }) // create the localization // const l10n = new PDFJSViewer.GenericL10n('en-GB') // TODO: locale mapping? // create the viewer const viewer = new PDFJSViewer.PDFViewer({ container: this.container, eventBus, imageResourcesPath, linkService, // l10n, // commented out since it currently breaks `aria-label` rendering in pdf pages enableScripting: false, // default is false, but set explicitly to be sure enableXfa: false, // default is false (2021-10-12), but set explicitly to be sure renderInteractiveForms: false, maxCanvasPixels: 8192 * 8192, // default is 4096 * 4096, increased for better resolution at high zoom levels annotationMode: PDFJS.AnnotationMode?.ENABLE, // enable annotations but not forms annotationEditorMode: PDFJS.AnnotationEditorType?.DISABLE, // disable annotation editing }) linkService.setViewer(viewer) this.eventBus = eventBus this.linkService = linkService this.viewer = viewer } // load a document from a URL loadDocument({ url, pdfFile, abortController, handleFetchError }) { // cancel any previous loading task if (this.loadDocumentTask) { this.loadDocumentTask.destroy() this.loadDocumentTask = undefined } return new Promise((resolve, reject) => { const rangeTransport = this.genPdfCachingTransport({ url, pdfFile, abortController, handleFetchError, }) let rangeChunkSize = DEFAULT_RANGE_CHUNK_SIZE if (rangeTransport && pdfFile.size < 2 * DEFAULT_RANGE_CHUNK_SIZE) { // pdf.js disables the "bulk" download optimization when providing a // custom range transport. Restore it by bumping the chunk size. rangeChunkSize = pdfFile.size } this.loadDocumentTask = this.PDFJS.getDocument({ url, cMapUrl: this.cMapUrl, cMapPacked: true, standardFontDataUrl: this.standardFontDataUrl, disableFontFace, rangeChunkSize, disableAutoFetch: true, disableStream, isEvalSupported: false, textLayerMode: 2, // PDFJSViewer.TextLayerMode.ENABLE, range: rangeTransport, }) this.loadDocumentTask.promise .then(doc => { if (!this.loadDocumentTask) { return // ignoring the response since loading task has been aborted } const previousDoc = this.viewer.pdfDocument this.viewer.setDocument(doc) this.linkService.setDocument(doc) resolve(doc) if (previousDoc) { previousDoc.cleanup().catch(debugConsole.error) previousDoc.destroy() } }) .catch(error => { if (this.loadDocumentTask) { if (!error || error.name !== 'MissingPDFException') { captureException(error, { tags: { handler: 'pdf-preview' }, }) } reject(error) } }) .finally(() => { this.loadDocumentTask = undefined }) }) } // update the current scale value if the container size changes updateOnResize() { if (!this.isVisible()) { return } // Use requestAnimationFrame to prevent errors like "ResizeObserver loop // completed with undelivered notifications" that can occur if updating the // viewer causes another repaint. The cost of this is that the viewer update // lags one frame behind, but it's unlikely to matter. // Further reading: https://github.com/WICG/resize-observer/issues/38 window.requestAnimationFrame(() => { const currentScaleValue = this.viewer.currentScaleValue if ( currentScaleValue === 'auto' || currentScaleValue === 'page-fit' || currentScaleValue === 'page-height' || currentScaleValue === 'page-width' ) { this.viewer.currentScaleValue = currentScaleValue } this.viewer.update() }) } // get the page and offset of a click event clickPosition(event, canvas, page) { if (!canvas) { return } const { viewport } = this.viewer.getPageView(page) const pageRect = canvas.getBoundingClientRect() const dx = event.clientX - pageRect.left const dy = event.clientY - pageRect.top const [left, top] = viewport.convertToPdfPoint(dx, dy) return { page, offset: { left, top: viewport.viewBox[3] - top, }, } } // get the current page, offset and page size get currentPosition() { const pageIndex = this.viewer.currentPageNumber - 1 const pageView = this.viewer.getPageView(pageIndex) const pageRect = pageView.div.getBoundingClientRect() const containerRect = this.container.getBoundingClientRect() const dy = containerRect.top - pageRect.top const dx = containerRect.left - pageRect.left const [left, top] = pageView.viewport.convertToPdfPoint(dx, dy) const [, , width, height] = pageView.viewport.viewBox return { page: pageIndex, offset: { top, left }, pageSize: { height, width }, } } scrollToPosition(position, scale = null) { const destArray = [ null, { name: 'XYZ', // 'XYZ' = scroll to the given coordinates }, position.offset.left, position.offset.top, scale, ] this.viewer.scrollPageIntoView({ pageNumber: position.page + 1, destArray, }) // scroll the page left and down by an extra few pixels to account for the pdf.js viewer page border const pageIndex = this.viewer.currentPageNumber - 1 const pageView = this.viewer.getPageView(pageIndex) const offset = parseFloat(getComputedStyle(pageView.div).borderWidth) this.viewer.container.scrollBy({ top: -offset, left: -offset, }) } isVisible() { return this.viewer.container.offsetParent !== null } abortDocumentLoading() { this.loadDocumentTask = undefined } destroy() { if (this.loadDocumentTask) { this.loadDocumentTask.destroy() this.loadDocumentTask = undefined } if (this.viewer) { this.viewer.destroy() } } }