| // Copyright 2014 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| /** |
| * Create a new PDFScriptingAPI. This provides a scripting interface to |
| * the PDF viewer so that it can be customized by things like print preview. |
| * @param {Window} window the window of the page containing the pdf viewer. |
| * @param {string} extensionUrl the url of the PDF extension. |
| */ |
| function PDFScriptingAPI(window, extensionUrl) { |
| this.extensionUrl_ = extensionUrl; |
| this.messageQueue_ = []; |
| window.addEventListener('message', function(event) { |
| if (event.origin != this.extensionUrl_) { |
| console.error('Received message that was not from the extension: ' + |
| event); |
| return; |
| } |
| switch (event.data.type) { |
| case 'readyToReceive': |
| this.setDestinationWindow(event.source); |
| break; |
| case 'viewport': |
| if (this.viewportChangedCallback_) |
| this.viewportChangedCallback_(event.data.pageX, |
| event.data.pageY, |
| event.data.pageWidth, |
| event.data.viewportWidth, |
| event.data.viewportHeight); |
| break; |
| case 'documentLoaded': |
| if (this.loadCallback_) |
| this.loadCallback_(); |
| break; |
| case 'getAccessibilityJSONReply': |
| if (this.accessibilityCallback_) { |
| this.accessibilityCallback_(event.data.json); |
| this.accessibilityCallback_ = null; |
| } |
| break; |
| } |
| }.bind(this), false); |
| } |
| |
| PDFScriptingAPI.prototype = { |
| /** |
| * @private |
| * Send a message to the extension. If we try to send messages prior to the |
| * extension being ready to receive messages (i.e. before it has finished |
| * loading) we queue up the messages and flush them later. |
| * @param {Object} message The message to send. |
| */ |
| sendMessage_: function(message) { |
| if (!this.pdfWindow_) { |
| this.messageQueue_.push(message); |
| return; |
| } |
| |
| this.pdfWindow_.postMessage(message, this.extensionUrl_); |
| }, |
| |
| /** |
| * Sets the destination window containing the PDF viewer. This will be called |
| * when a 'readyToReceive' message is received from the PDF viewer or it can |
| * be called during tests. It then flushes any pending messages to the window. |
| * @param {Window} pdfWindow the window containing the PDF viewer. |
| */ |
| setDestinationWindow: function(pdfWindow) { |
| this.pdfWindow_ = pdfWindow; |
| while (this.messageQueue_.length != 0) { |
| this.pdfWindow_.postMessage(this.messageQueue_.shift(), |
| this.extensionUrl_); |
| } |
| }, |
| |
| /** |
| * Sets the callback which will be run when the PDF viewport changes. |
| * @param {Function} callback the callback to be called. |
| */ |
| setViewportChangedCallback: function(callback) { |
| this.viewportChangedCallback_ = callback; |
| }, |
| |
| /** |
| * Sets the callback which will be run when the PDF document has finished |
| * loading. |
| * @param {Function} callback the callback to be called. |
| */ |
| setLoadCallback: function(callback) { |
| this.loadCallback_ = callback; |
| }, |
| |
| /** |
| * Resets the PDF viewer into print preview mode. |
| * @param {string} url the url of the PDF to load. |
| * @param {boolean} grayscale whether or not to display the PDF in grayscale. |
| * @param {Array.<number>} pageNumbers an array of the page numbers. |
| * @param {boolean} modifiable whether or not the document is modifiable. |
| */ |
| resetPrintPreviewMode: function(url, grayscale, pageNumbers, modifiable) { |
| this.sendMessage_({ |
| type: 'resetPrintPreviewMode', |
| url: url, |
| grayscale: grayscale, |
| pageNumbers: pageNumbers, |
| modifiable: modifiable |
| }); |
| }, |
| |
| /** |
| * Load a page into the document while in print preview mode. |
| * @param {string} url the url of the pdf page to load. |
| * @param {number} index the index of the page to load. |
| */ |
| loadPreviewPage: function(url, index) { |
| this.sendMessage_({ |
| type: 'loadPreviewPage', |
| url: url, |
| index: index |
| }); |
| }, |
| |
| /** |
| * Get accessibility JSON for the document. |
| * @param {Function} callback a callback to be called with the accessibility |
| * json that has been retrieved. |
| * @param {number} [page] the 0-indexed page number to get accessibility data |
| * for. If this is not provided, data about the entire document is |
| * returned. |
| * @return {boolean} true if the function is successful, false if there is an |
| * outstanding request for accessibility data that has not been answered. |
| */ |
| getAccessibilityJSON: function(callback, page) { |
| if (this.accessibilityCallback_) |
| return false; |
| this.accessibilityCallback_ = callback; |
| var message = { |
| type: 'getAccessibilityJSON', |
| }; |
| if (page || page == 0) |
| message.page = page; |
| this.sendMessage_(message); |
| return true; |
| }, |
| |
| /** |
| * Send a key event to the extension. |
| * @param {number} keyCode the key code to send to the extension. |
| */ |
| sendKeyEvent: function(keyCode) { |
| this.sendMessage_({ |
| type: 'sendKeyEvent', |
| keyCode: keyCode |
| }); |
| }, |
| }; |
| |
| /** |
| * Creates a PDF viewer with a scripting interface. This is basically 1) an |
| * iframe which is navigated to the PDF viewer extension and 2) a scripting |
| * interface which provides access to various features of the viewer for use |
| * by print preview and accessibility. |
| * @param {string} src the source URL of the PDF to load initially. |
| * @return {HTMLIFrameElement} the iframe element containing the PDF viewer. |
| */ |
| function PDFCreateOutOfProcessPlugin(src) { |
| var EXTENSION_URL = 'chrome-extension://mhjfbmdgcfjbbpaeojofohoefgiehjai'; |
| var iframe = window.document.createElement('iframe'); |
| iframe.setAttribute('src', EXTENSION_URL + '/index.html?' + src); |
| var client = new PDFScriptingAPI(window, EXTENSION_URL); |
| |
| // Add the functions to the iframe so that they can be called directly. |
| iframe.setViewportChangedCallback = |
| client.setViewportChangedCallback.bind(client); |
| iframe.setLoadCallback = client.setLoadCallback.bind(client); |
| iframe.resetPrintPreviewMode = client.resetPrintPreviewMode.bind(client); |
| iframe.loadPreviewPage = client.loadPreviewPage.bind(client); |
| iframe.sendKeyEvent = client.sendKeyEvent.bind(client); |
| return iframe; |
| } |