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if (!pdfjsLib.getDocument || !pdfjsViewer.PDFViewer) {  // eslint-disable-next-line no-alert  alert("Please build the pdfjs-dist library using\n `gulp dist-install`");}var USE_ONLY_CSS_ZOOM = true;var TEXT_LAYER_MODE = 0; // DISABLEvar MAX_IMAGE_SIZE = 1024 * 1024;var CMAP_URL = "../../node_modules/pdfjs-dist/cmaps/";var CMAP_PACKED = true;pdfjsLib.GlobalWorkerOptions.workerSrc =  "../../node_modules/pdfjs-dist/build/pdf.worker.js";var DEFAULT_URL = "../../web/compressed.tracemonkey-pldi-09.pdf";var DEFAULT_SCALE_DELTA = 1.1;var MIN_SCALE = 0.25;var MAX_SCALE = 10.0;var DEFAULT_SCALE_VALUE = "auto";var PDFViewerApplication = {  pdfLoadingTask: null,  pdfDocument: null,  pdfViewer: null,  pdfHistory: null,  pdfLinkService: null,  eventBus: null,  /**   * Opens PDF document specified by URL.   * @returns {Promise} - Returns the promise, which is resolved when document   *                      is opened.   */  open(params) {    if (this.pdfLoadingTask) {      // We need to destroy already opened document      return this.close().then(        function () {          // ... and repeat the open() call.          return this.open(params);        }.bind(this)      );    }    var url = params.url;    var self = this;    this.setTitleUsingUrl(url);    // Loading document.    var loadingTask = pdfjsLib.getDocument({      url,      maxImageSize: MAX_IMAGE_SIZE,      cMapUrl: CMAP_URL,      cMapPacked: CMAP_PACKED,    });    this.pdfLoadingTask = loadingTask;    loadingTask.onProgress = function (progressData) {      self.progress(progressData.loaded / progressData.total);    };    return loadingTask.promise.then(      function (pdfDocument) {        // Document loaded, specifying document for the viewer.        self.pdfDocument = pdfDocument;        self.pdfViewer.setDocument(pdfDocument);        self.pdfLinkService.setDocument(pdfDocument);        self.pdfHistory.initialize({ fingerprint: pdfDocument.fingerprint });        self.loadingBar.hide();        self.setTitleUsingMetadata(pdfDocument);      },      function (exception) {        var message = exception && exception.message;        var l10n = self.l10n;        var loadingErrorMessage;        if (exception instanceof pdfjsLib.InvalidPDFException) {          // change error message also for other builds          loadingErrorMessage = l10n.get(            "invalid_file_error",            null,            "Invalid or corrupted PDF file."          );        } else if (exception instanceof pdfjsLib.MissingPDFException) {          // special message for missing PDFs          loadingErrorMessage = l10n.get(            "missing_file_error",            null,            "Missing PDF file."          );        } else if (exception instanceof pdfjsLib.UnexpectedResponseException) {          loadingErrorMessage = l10n.get(            "unexpected_response_error",            null,            "Unexpected server response."          );        } else {          loadingErrorMessage = l10n.get(            "loading_error",            null,            "An error occurred while loading the PDF."          );        }        loadingErrorMessage.then(function (msg) {          self.error(msg, { message });        });        self.loadingBar.hide();      }    );  },  /**   * Closes opened PDF document.   * @returns {Promise} - Returns the promise, which is resolved when all   *                      destruction is completed.   */  close() {    var errorWrapper = document.getElementById("errorWrapper");    errorWrapper.setAttribute("hidden", "true");    if (!this.pdfLoadingTask) {      return Promise.resolve();    }    var promise = this.pdfLoadingTask.destroy();    this.pdfLoadingTask = null;    if (this.pdfDocument) {      this.pdfDocument = null;      this.pdfViewer.setDocument(null);      this.pdfLinkService.setDocument(null, null);      if (this.pdfHistory) {        this.pdfHistory.reset();      }    }    return promise;  },  get loadingBar() {    var bar = new pdfjsViewer.ProgressBar("#loadingBar", {});    return pdfjsLib.shadow(this, "loadingBar", bar);  },  setTitleUsingUrl: function pdfViewSetTitleUsingUrl(url) {    this.url = url;    var title = pdfjsLib.getFilenameFromUrl(url) || url;    try {      title = decodeURIComponent(title);    } catch (e) {      // decodeURIComponent may throw URIError,      // fall back to using the unprocessed url in that case    }    this.setTitle(title);  },  setTitleUsingMetadata(pdfDocument) {    var self = this;    pdfDocument.getMetadata().then(function (data) {      var info = data.info,        metadata = data.metadata;      self.documentInfo = info;      self.metadata = metadata;      // Provides some basic debug information      console.log(        "PDF " +          pdfDocument.fingerprint +          " [" +          info.PDFFormatVersion +          " " +          (info.Producer || "-").trim() +          " / " +          (info.Creator || "-").trim() +          "]" +          " (PDF.js: " +          (pdfjsLib.version || "-") +          ")"      );      var pdfTitle;      if (metadata && metadata.has("dc:title")) {        var title = metadata.get("dc:title");        // Ghostscript sometimes returns 'Untitled', so prevent setting the        // title to 'Untitled.        if (title !== "Untitled") {          pdfTitle = title;        }      }      if (!pdfTitle && info && info.Title) {        pdfTitle = info.Title;      }      if (pdfTitle) {        self.setTitle(pdfTitle + " - " + document.title);      }    });  },  setTitle: function pdfViewSetTitle(title) {    document.title = title;    document.getElementById("title").textContent = title;  },  error: function pdfViewError(message, moreInfo) {    var l10n = this.l10n;    var moreInfoText = [      l10n.get(        "error_version_info",        { version: pdfjsLib.version || "?", build: pdfjsLib.build || "?" },        "PDF.js v{{version}} (build: {{build}})"      ),    ];    if (moreInfo) {      moreInfoText.push(        l10n.get(          "error_message",          { message: moreInfo.message },          "Message: {{message}}"        )      );      if (moreInfo.stack) {        moreInfoText.push(          l10n.get("error_stack", { stack: moreInfo.stack }, "Stack: {{stack}}")        );      } else {        if (moreInfo.filename) {          moreInfoText.push(            l10n.get(              "error_file",              { file: moreInfo.filename },              "File: {{file}}"            )          );        }        if (moreInfo.lineNumber) {          moreInfoText.push(            l10n.get(              "error_line",              { line: moreInfo.lineNumber },              "Line: {{line}}"            )          );        }      }    }    var errorWrapper = document.getElementById("errorWrapper");    errorWrapper.removeAttribute("hidden");    var errorMessage = document.getElementById("errorMessage");    errorMessage.textContent = message;    var closeButton = document.getElementById("errorClose");    closeButton.onclick = function () {      errorWrapper.setAttribute("hidden", "true");    };    var errorMoreInfo = document.getElementById("errorMoreInfo");    var moreInfoButton = document.getElementById("errorShowMore");    var lessInfoButton = document.getElementById("errorShowLess");    moreInfoButton.onclick = function () {      errorMoreInfo.removeAttribute("hidden");      moreInfoButton.setAttribute("hidden", "true");      lessInfoButton.removeAttribute("hidden");      errorMoreInfo.style.height = errorMoreInfo.scrollHeight + "px";    };    lessInfoButton.onclick = function () {      errorMoreInfo.setAttribute("hidden", "true");      moreInfoButton.removeAttribute("hidden");      lessInfoButton.setAttribute("hidden", "true");    };    moreInfoButton.removeAttribute("hidden");    lessInfoButton.setAttribute("hidden", "true");    Promise.all(moreInfoText).then(function (parts) {      errorMoreInfo.value = parts.join("\n");    });  },  progress: function pdfViewProgress(level) {    var percent = Math.round(level * 100);    // Updating the bar if value increases.    if (percent > this.loadingBar.percent || isNaN(percent)) {      this.loadingBar.percent = percent;    }  },  get pagesCount() {    return this.pdfDocument.numPages;  },  get page() {    return this.pdfViewer.currentPageNumber;  },  set page(val) {    this.pdfViewer.currentPageNumber = val;  },  zoomIn: function pdfViewZoomIn(ticks) {    var newScale = this.pdfViewer.currentScale;    do {      newScale = (newScale * DEFAULT_SCALE_DELTA).toFixed(2);      newScale = Math.ceil(newScale * 10) / 10;      newScale = Math.min(MAX_SCALE, newScale);    } while (--ticks && newScale < MAX_SCALE);    this.pdfViewer.currentScaleValue = newScale;  },  zoomOut: function pdfViewZoomOut(ticks) {    var newScale = this.pdfViewer.currentScale;    do {      newScale = (newScale / DEFAULT_SCALE_DELTA).toFixed(2);      newScale = Math.floor(newScale * 10) / 10;      newScale = Math.max(MIN_SCALE, newScale);    } while (--ticks && newScale > MIN_SCALE);    this.pdfViewer.currentScaleValue = newScale;  },  initUI: function pdfViewInitUI() {    var eventBus = new pdfjsViewer.EventBus();    this.eventBus = eventBus;    var linkService = new pdfjsViewer.PDFLinkService({      eventBus,    });    this.pdfLinkService = linkService;    this.l10n = pdfjsViewer.NullL10n;    var container = document.getElementById("viewerContainer");    var pdfViewer = new pdfjsViewer.PDFViewer({      container,      eventBus,      linkService,      l10n: this.l10n,      useOnlyCssZoom: USE_ONLY_CSS_ZOOM,      textLayerMode: TEXT_LAYER_MODE,    });    this.pdfViewer = pdfViewer;    linkService.setViewer(pdfViewer);    this.pdfHistory = new pdfjsViewer.PDFHistory({      eventBus,      linkService,    });    linkService.setHistory(this.pdfHistory);    document.getElementById("previous").addEventListener("click", function () {      PDFViewerApplication.page--;    });    document.getElementById("next").addEventListener("click", function () {      PDFViewerApplication.page++;    });    document.getElementById("zoomIn").addEventListener("click", function () {      PDFViewerApplication.zoomIn();    });    document.getElementById("zoomOut").addEventListener("click", function () {      PDFViewerApplication.zoomOut();    });    document      .getElementById("pageNumber")      .addEventListener("click", function () {        this.select();      });    document      .getElementById("pageNumber")      .addEventListener("change", function () {        PDFViewerApplication.page = this.value | 0;        // Ensure that the page number input displays the correct value,        // even if the value entered by the user was invalid        // (e.g. a floating point number).        if (this.value !== PDFViewerApplication.page.toString()) {          this.value = PDFViewerApplication.page;        }      });    eventBus.on("pagesinit", function () {      // We can use pdfViewer now, e.g. let's change default scale.      pdfViewer.currentScaleValue = DEFAULT_SCALE_VALUE;    });    eventBus.on(      "pagechanging",      function (evt) {        var page = evt.pageNumber;        var numPages = PDFViewerApplication.pagesCount;        document.getElementById("pageNumber").value = page;        document.getElementById("previous").disabled = page <= 1;        document.getElementById("next").disabled = page >= numPages;      },      true    );  },};document.addEventListener(  "DOMContentLoaded",  function () {    PDFViewerApplication.initUI();  },  true);(function animationStartedClosure() {  // The offsetParent is not set until the PDF.js iframe or object is visible.  // Waiting for first animation.  PDFViewerApplication.animationStartedPromise = new Promise(function (    resolve) {    window.requestAnimationFrame(resolve);  });})();// We need to delay opening until all HTML is loaded.PDFViewerApplication.animationStartedPromise.then(function () {  PDFViewerApplication.open({    url: DEFAULT_URL,  });});