/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
/* 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.
*/
/* globals PDFViewerApplication */
'use strict';
var DELAY_BEFORE_HIDING_CONTROLS = 3000; // in ms
var SELECTOR = 'presentationControls';
var DELAY_BEFORE_RESETTING_SWITCH_IN_PROGRESS = 1000; // in ms
/**
* @typedef {Object} PDFPresentationModeOptions
* @property {HTMLDivElement} container - The container for the viewer element.
* @property {HTMLDivElement} viewer - (optional) The viewer element.
* @property {PDFThumbnailViewer} pdfThumbnailViewer - (optional) The thumbnail
* viewer.
* @property {Array} contextMenuItems - (optional) The menuitems that are added
* to the context menu in Presentation Mode.
*/
var PDFPresentationMode = {
initialized: false,
active: false,
args: null,
contextMenuOpen: false,
mouseScrollTimeStamp: 0,
mouseScrollDelta: 0,
/**
* @param {PDFPresentationModeOptions} options
*/
initialize: function pdfPresentationModeInitialize(options) {
this.initialized = true;
this.container = options.container;
this.viewer = options.viewer || options.container.firstElementChild;
this.pdfThumbnailViewer = options.pdfThumbnailViewer || null;
var contextMenuItems = options.contextMenuItems || null;
window.addEventListener('fullscreenchange', this._fullscreenChange);
window.addEventListener('mozfullscreenchange', this._fullscreenChange);
//#if !(FIREFOX || MOZCENTRAL)
window.addEventListener('webkitfullscreenchange', this._fullscreenChange);
window.addEventListener('MSFullscreenChange', this._fullscreenChange);
//#endif
if (contextMenuItems) {
for (var i = 0, ii = contextMenuItems.length; i < ii; i++) {
var item = contextMenuItems[i];
item.element.addEventListener('click', function (handler) {
this.contextMenuOpen = false;
handler();
}.bind(this, item.handler));
}
}
},
/**
* Request the browser to enter fullscreen mode.
* @returns {boolean} Indicating if the request was successful.
*/
request: function pdfPresentationModeRequest() {
if (!this.initialized || this.switchInProgress || this.active ||
!this.viewer.hasChildNodes()) {
return false;
}
this._setSwitchInProgress();
this._notifyStateChange();
if (this.container.requestFullscreen) {
this.container.requestFullscreen();
} else if (this.container.mozRequestFullScreen) {
this.container.mozRequestFullScreen();
} else if (this.container.webkitRequestFullscreen) {
this.container.webkitRequestFullscreen(Element.ALLOW_KEYBOARD_INPUT);
} else if (this.container.msRequestFullscreen) {
this.container.msRequestFullscreen();
} else {
return false;
}
this.args = {
page: PDFViewerApplication.page,
previousScale: PDFViewerApplication.currentScaleValue
};
return true;
},
/**
* Switches page when the user scrolls (using a scroll wheel or a touchpad)
* with large enough motion, to prevent accidental page switches.
* @param {number} delta - The delta value from the mouse event.
*/
mouseScroll: function pdfPresentationModeMouseScroll(delta) {
if (!this.initialized && !this.active) {
return;
}
var MOUSE_SCROLL_COOLDOWN_TIME = 50;
var PAGE_SWITCH_THRESHOLD = 120;
var PageSwitchDirection = {
UP: -1,
DOWN: 1
};
var currentTime = (new Date()).getTime();
var storedTime = this.mouseScrollTimeStamp;
// If we've already switched page, avoid accidentally switching page again.
if (currentTime > storedTime &&
currentTime - storedTime < MOUSE_SCROLL_COOLDOWN_TIME) {
return;
}
// If the user changes scroll direction, reset the accumulated scroll delta.
if ((this.mouseScrollDelta > 0 && delta < 0) ||
(this.mouseScrollDelta < 0 && delta > 0)) {
this._resetMouseScrollState();
}
this.mouseScrollDelta += delta;
if (Math.abs(this.mouseScrollDelta) >= PAGE_SWITCH_THRESHOLD) {
var pageSwitchDirection = (this.mouseScrollDelta > 0) ?
PageSwitchDirection.UP : PageSwitchDirection.DOWN;
var page = PDFViewerApplication.page;
this._resetMouseScrollState();
// If we're already on the first/last page, we don't need to do anything.
if ((page === 1 && pageSwitchDirection === PageSwitchDirection.UP) ||
(page === PDFViewerApplication.pagesCount &&
pageSwitchDirection === PageSwitchDirection.DOWN)) {
return;
}
PDFViewerApplication.page = (page + pageSwitchDirection);
this.mouseScrollTimeStamp = currentTime;
}
},
get isFullscreen() {
return !!(document.fullscreenElement ||
document.mozFullScreen ||
document.webkitIsFullScreen ||
document.msFullscreenElement);
},
/**
* @private
*/
_fullscreenChange: function pdfPresentationModeFullscreenChange() {
var self = PDFPresentationMode;
if (self.isFullscreen) {
self._enter();
} else {
self._exit();
}
},
/**
* @private
*/
_notifyStateChange: function pdfPresentationModeNotifyStateChange() {
var self = PDFPresentationMode;
var event = document.createEvent('CustomEvent');
event.initCustomEvent('presentationmodechanged', true, true, {
active: self.active,
switchInProgress: !!self.switchInProgress
});
window.dispatchEvent(event);
},
/**
* Used to initialize a timeout when requesting Presentation Mode,
* i.e. when the browser is requested to enter fullscreen mode.
* This timeout is used to prevent the current page from being scrolled
* partially, or completely, out of view when entering Presentation Mode.
* NOTE: This issue seems limited to certain zoom levels (e.g. 'page-width').
* @private
*/
_setSwitchInProgress: function pdfPresentationMode_setSwitchInProgress() {
if (this.switchInProgress) {
clearTimeout(this.switchInProgress);
}
this.switchInProgress = setTimeout(function switchInProgressTimeout() {
delete this.switchInProgress;
this._notifyStateChange();
}.bind(this), DELAY_BEFORE_RESETTING_SWITCH_IN_PROGRESS);
},
/**
* @private
*/
_resetSwitchInProgress: function pdfPresentationMode_resetSwitchInProgress() {
if (this.switchInProgress) {
clearTimeout(this.switchInProgress);
delete this.switchInProgress;
}
},
/**
* @private
*/
_enter: function pdfPresentationModeEnter() {
this.active = true;
this._resetSwitchInProgress();
this._notifyStateChange();
// Ensure that the correct page is scrolled into view when entering
// Presentation Mode, by waiting until fullscreen mode in enabled.
setTimeout(function enterPresentationModeTimeout() {
PDFViewerApplication.page = this.args.page;
PDFViewerApplication.setScale('page-fit', true);
}.bind(this), 0);
window.addEventListener('mousemove', this._showControls, false);
window.addEventListener('mousedown', this._mouseDown, false);
window.addEventListener('keydown', this._resetMouseScrollState, false);
window.addEventListener('contextmenu', this._contextMenu, false);
this._showControls();
this.contextMenuOpen = false;
this.container.setAttribute('contextmenu', 'viewerContextMenu');
// Text selection is disabled in Presentation Mode, thus it's not possible
// for the user to deselect text that is selected (e.g. with "Select all")
// when entering Presentation Mode, hence we remove any active selection.
window.getSelection().removeAllRanges();
},
/**
* @private
*/
_exit: function pdfPresentationModeExit() {
var page = PDFViewerApplication.page;
// Ensure that the correct page is scrolled into view when exiting
// Presentation Mode, by waiting until fullscreen mode is disabled.
setTimeout(function exitPresentationModeTimeout() {
this.active = false;
this._notifyStateChange();
PDFViewerApplication.setScale(this.args.previousScale, true);
PDFViewerApplication.page = page;
this.args = null;
}.bind(this), 0);
window.removeEventListener('mousemove', this._showControls, false);
window.removeEventListener('mousedown', this._mouseDown, false);
window.removeEventListener('keydown', this._resetMouseScrollState, false);
window.removeEventListener('contextmenu', this._contextMenu, false);
this._hideControls();
this._resetMouseScrollState();
this.container.removeAttribute('contextmenu');
this.contextMenuOpen = false;
if (this.pdfThumbnailViewer) {
this.pdfThumbnailViewer.ensureThumbnailVisible(page);
}
},
/**
* @private
*/
_mouseDown: function pdfPresentationModeMouseDown(evt) {
var self = PDFPresentationMode;
if (self.contextMenuOpen) {
self.contextMenuOpen = false;
evt.preventDefault();
return;
}
if (evt.button === 0) {
// Enable clicking of links in presentation mode. Please note:
// Only links pointing to destinations in the current PDF document work.
var isInternalLink = (evt.target.href &&
evt.target.classList.contains('internalLink'));
if (!isInternalLink) {
// Unless an internal link was clicked, advance one page.
evt.preventDefault();
PDFViewerApplication.page += (evt.shiftKey ? -1 : 1);
}
}
},
/**
* @private
*/
_contextMenu: function pdfPresentationModeContextMenu(evt) {
PDFPresentationMode.contextMenuOpen = true;
},
/**
* @private
*/
_showControls: function pdfPresentationModeShowControls() {
var self = PDFPresentationMode;
if (self.controlsTimeout) {
clearTimeout(self.controlsTimeout);
} else {
self.container.classList.add(SELECTOR);
}
self.controlsTimeout = setTimeout(function showControlsTimeout() {
self.container.classList.remove(SELECTOR);
delete self.controlsTimeout;
}, DELAY_BEFORE_HIDING_CONTROLS);
},
/**
* @private
*/
_hideControls: function pdfPresentationModeHideControls() {
var self = PDFPresentationMode;
if (!self.controlsTimeout) {
return;
}
clearTimeout(self.controlsTimeout);
self.container.classList.remove(SELECTOR);
delete self.controlsTimeout;
},
/**
* Resets the properties used for tracking mouse scrolling events.
* @private
*/
_resetMouseScrollState: function pdfPresentationModeResetMouseScrollState() {
var self = PDFPresentationMode;
self.mouseScrollTimeStamp = 0;
self.mouseScrollDelta = 0;
}
};