pdfjs-dist/lib/web/pdf_print_service.js

/**
 * @licstart The following is the entire license notice for the
 * Javascript code in this page
 *
 * Copyright 2021 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * @licend The above is the entire license notice for the
 * Javascript code in this page
 */
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.PDFPrintService = PDFPrintService;

var _app = require("./app.js");

var _viewer_compatibility = require("./viewer_compatibility.js");

let activeService = null;
let overlayManager = null;

function renderPage(activeServiceOnEntry, pdfDocument, pageNumber, size, printResolution, optionalContentConfigPromise) {
  const scratchCanvas = activeService.scratchCanvas;
  const PRINT_UNITS = printResolution / 72.0;
  scratchCanvas.width = Math.floor(size.width * PRINT_UNITS);
  scratchCanvas.height = Math.floor(size.height * PRINT_UNITS);
  const ctx = scratchCanvas.getContext("2d");
  ctx.save();
  ctx.fillStyle = "rgb(255, 255, 255)";
  ctx.fillRect(0, 0, scratchCanvas.width, scratchCanvas.height);
  ctx.restore();
  return pdfDocument.getPage(pageNumber).then(function (pdfPage) {
    const renderContext = {
      canvasContext: ctx,
      transform: [PRINT_UNITS, 0, 0, PRINT_UNITS, 0, 0],
      viewport: pdfPage.getViewport({
        scale: 1,
        rotation: size.rotation
      }),
      intent: "print",
      annotationStorage: pdfDocument.annotationStorage,
      optionalContentConfigPromise
    };
    return pdfPage.render(renderContext).promise;
  });
}

function PDFPrintService(pdfDocument, pagesOverview, printContainer, printResolution, optionalContentConfigPromise = null, l10n) {
  this.pdfDocument = pdfDocument;
  this.pagesOverview = pagesOverview;
  this.printContainer = printContainer;
  this._printResolution = printResolution || 150;
  this._optionalContentConfigPromise = optionalContentConfigPromise || pdfDocument.getOptionalContentConfig();
  this.l10n = l10n;
  this.currentPage = -1;
  this.scratchCanvas = document.createElement("canvas");
}

PDFPrintService.prototype = {
  layout() {
    this.throwIfInactive();
    const body = document.querySelector("body");
    body.setAttribute("data-pdfjsprinting", true);
    const hasEqualPageSizes = this.pagesOverview.every(function (size) {
      return size.width === this.pagesOverview[0].width && size.height === this.pagesOverview[0].height;
    }, this);

    if (!hasEqualPageSizes) {
      console.warn("Not all pages have the same size. The printed " + "result may be incorrect!");
    }

    this.pageStyleSheet = document.createElement("style");
    const pageSize = this.pagesOverview[0];
    this.pageStyleSheet.textContent = "@page { size: " + pageSize.width + "pt " + pageSize.height + "pt;}";
    body.appendChild(this.pageStyleSheet);
  },

  destroy() {
    if (activeService !== this) {
      return;
    }

    this.printContainer.textContent = "";
    const body = document.querySelector("body");
    body.removeAttribute("data-pdfjsprinting");

    if (this.pageStyleSheet) {
      this.pageStyleSheet.remove();
      this.pageStyleSheet = null;
    }

    this.scratchCanvas.width = this.scratchCanvas.height = 0;
    this.scratchCanvas = null;
    activeService = null;
    ensureOverlay().then(function () {
      if (overlayManager.active !== "printServiceOverlay") {
        return;
      }

      overlayManager.close("printServiceOverlay");
    });
  },

  renderPages() {
    const pageCount = this.pagesOverview.length;

    const renderNextPage = (resolve, reject) => {
      this.throwIfInactive();

      if (++this.currentPage >= pageCount) {
        renderProgress(pageCount, pageCount, this.l10n);
        resolve();
        return;
      }

      const index = this.currentPage;
      renderProgress(index, pageCount, this.l10n);
      renderPage(this, this.pdfDocument, index + 1, this.pagesOverview[index], this._printResolution, this._optionalContentConfigPromise).then(this.useRenderedPage.bind(this)).then(function () {
        renderNextPage(resolve, reject);
      }, reject);
    };

    return new Promise(renderNextPage);
  },

  useRenderedPage() {
    this.throwIfInactive();
    const img = document.createElement("img");
    const scratchCanvas = this.scratchCanvas;

    if ("toBlob" in scratchCanvas && !_viewer_compatibility.viewerCompatibilityParams.disableCreateObjectURL) {
      scratchCanvas.toBlob(function (blob) {
        img.src = URL.createObjectURL(blob);
      });
    } else {
      img.src = scratchCanvas.toDataURL();
    }

    const wrapper = document.createElement("div");
    wrapper.appendChild(img);
    this.printContainer.appendChild(wrapper);
    return new Promise(function (resolve, reject) {
      img.onload = resolve;
      img.onerror = reject;
    });
  },

  performPrint() {
    this.throwIfInactive();
    return new Promise(resolve => {
      setTimeout(() => {
        if (!this.active) {
          resolve();
          return;
        }

        print.call(window);
        setTimeout(resolve, 20);
      }, 0);
    });
  },

  get active() {
    return this === activeService;
  },

  throwIfInactive() {
    if (!this.active) {
      throw new Error("This print request was cancelled or completed.");
    }
  }

};
const print = window.print;

window.print = function () {
  if (activeService) {
    console.warn("Ignored window.print() because of a pending print job.");
    return;
  }

  ensureOverlay().then(function () {
    if (activeService) {
      overlayManager.open("printServiceOverlay");
    }
  });

  try {
    dispatchEvent("beforeprint");
  } finally {
    if (!activeService) {
      console.error("Expected print service to be initialized.");
      ensureOverlay().then(function () {
        if (overlayManager.active === "printServiceOverlay") {
          overlayManager.close("printServiceOverlay");
        }
      });
      return;
    }

    const activeServiceOnEntry = activeService;
    activeService.renderPages().then(function () {
      return activeServiceOnEntry.performPrint();
    }).catch(function () {}).then(function () {
      if (activeServiceOnEntry.active) {
        abort();
      }
    });
  }
};

function dispatchEvent(eventType) {
  const event = document.createEvent("CustomEvent");
  event.initCustomEvent(eventType, false, false, "custom");
  window.dispatchEvent(event);
}

function abort() {
  if (activeService) {
    activeService.destroy();
    dispatchEvent("afterprint");
  }
}

function renderProgress(index, total, l10n) {
  const progressContainer = document.getElementById("printServiceOverlay");
  const progress = Math.round(100 * index / total);
  const progressBar = progressContainer.querySelector("progress");
  const progressPerc = progressContainer.querySelector(".relative-progress");
  progressBar.value = progress;
  l10n.get("print_progress_percent", {
    progress
  }).then(msg => {
    progressPerc.textContent = msg;
  });
}

window.addEventListener("keydown", function (event) {
  if (event.keyCode === 80 && (event.ctrlKey || event.metaKey) && !event.altKey && (!event.shiftKey || window.chrome || window.opera)) {
    window.print();
    event.preventDefault();

    if (event.stopImmediatePropagation) {
      event.stopImmediatePropagation();
    } else {
      event.stopPropagation();
    }
  }
}, true);

if ("onbeforeprint" in window) {
  const stopPropagationIfNeeded = function (event) {
    if (event.detail !== "custom" && event.stopImmediatePropagation) {
      event.stopImmediatePropagation();
    }
  };

  window.addEventListener("beforeprint", stopPropagationIfNeeded);
  window.addEventListener("afterprint", stopPropagationIfNeeded);
}

let overlayPromise;

function ensureOverlay() {
  if (!overlayPromise) {
    overlayManager = _app.PDFViewerApplication.overlayManager;

    if (!overlayManager) {
      throw new Error("The overlay manager has not yet been initialized.");
    }

    overlayPromise = overlayManager.register("printServiceOverlay", document.getElementById("printServiceOverlay"), abort, true);
    document.getElementById("printCancel").onclick = abort;
  }

  return overlayPromise;
}

_app.PDFPrintServiceFactory.instance = {
  supportsPrinting: true,

  createPrintService(pdfDocument, pagesOverview, printContainer, printResolution, optionalContentConfigPromise, l10n) {
    if (activeService) {
      throw new Error("The print service is created and active.");
    }

    activeService = new PDFPrintService(pdfDocument, pagesOverview, printContainer, printResolution, optionalContentConfigPromise, l10n);
    return activeService;
  }

};