pdfjs-dist/lib/web/pdf_presentation_mode.js

/* Copyright 2017 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.
 */
'use strict';
var uiUtils = require('./ui_utils.js');
var normalizeWheelEventDelta = uiUtils.normalizeWheelEventDelta;
var DELAY_BEFORE_RESETTING_SWITCH_IN_PROGRESS = 1500;
var DELAY_BEFORE_HIDING_CONTROLS = 3000;
var ACTIVE_SELECTOR = 'pdfPresentationMode';
var CONTROLS_SELECTOR = 'pdfPresentationModeControls';
var PDFPresentationMode = function PDFPresentationModeClosure() {
 function PDFPresentationMode(options) {
  this.container = options.container;
  this.viewer = options.viewer || options.container.firstElementChild;
  this.pdfViewer = options.pdfViewer;
  this.eventBus = options.eventBus;
  var contextMenuItems = options.contextMenuItems || null;
  this.active = false;
  this.args = null;
  this.contextMenuOpen = false;
  this.mouseScrollTimeStamp = 0;
  this.mouseScrollDelta = 0;
  this.touchSwipeState = null;
  if (contextMenuItems) {
   contextMenuItems.contextFirstPage.addEventListener('click', function PDFPresentationMode_contextFirstPageClick(e) {
    this.contextMenuOpen = false;
    this.eventBus.dispatch('firstpage');
   }.bind(this));
   contextMenuItems.contextLastPage.addEventListener('click', function PDFPresentationMode_contextLastPageClick(e) {
    this.contextMenuOpen = false;
    this.eventBus.dispatch('lastpage');
   }.bind(this));
   contextMenuItems.contextPageRotateCw.addEventListener('click', function PDFPresentationMode_contextPageRotateCwClick(e) {
    this.contextMenuOpen = false;
    this.eventBus.dispatch('rotatecw');
   }.bind(this));
   contextMenuItems.contextPageRotateCcw.addEventListener('click', function PDFPresentationMode_contextPageRotateCcwClick(e) {
    this.contextMenuOpen = false;
    this.eventBus.dispatch('rotateccw');
   }.bind(this));
  }
 }
 PDFPresentationMode.prototype = {
  request: function PDFPresentationMode_request() {
   if (this.switchInProgress || this.active || !this.viewer.hasChildNodes()) {
    return false;
   }
   this._addFullscreenChangeListeners();
   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: this.pdfViewer.currentPageNumber,
    previousScale: this.pdfViewer.currentScaleValue
   };
   return true;
  },
  _mouseWheel: function PDFPresentationMode_mouseWheel(evt) {
   if (!this.active) {
    return;
   }
   evt.preventDefault();
   var delta = normalizeWheelEventDelta(evt);
   var MOUSE_SCROLL_COOLDOWN_TIME = 50;
   var PAGE_SWITCH_THRESHOLD = 0.1;
   var currentTime = new Date().getTime();
   var storedTime = this.mouseScrollTimeStamp;
   if (currentTime > storedTime && currentTime - storedTime < MOUSE_SCROLL_COOLDOWN_TIME) {
    return;
   }
   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 totalDelta = this.mouseScrollDelta;
    this._resetMouseScrollState();
    var success = totalDelta > 0 ? this._goToPreviousPage() : this._goToNextPage();
    if (success) {
     this.mouseScrollTimeStamp = currentTime;
    }
   }
  },
  get isFullscreen() {
   return !!(document.fullscreenElement || document.mozFullScreen || document.webkitIsFullScreen || document.msFullscreenElement);
  },
  _goToPreviousPage: function PDFPresentationMode_goToPreviousPage() {
   var page = this.pdfViewer.currentPageNumber;
   if (page <= 1) {
    return false;
   }
   this.pdfViewer.currentPageNumber = page - 1;
   return true;
  },
  _goToNextPage: function PDFPresentationMode_goToNextPage() {
   var page = this.pdfViewer.currentPageNumber;
   if (page >= this.pdfViewer.pagesCount) {
    return false;
   }
   this.pdfViewer.currentPageNumber = page + 1;
   return true;
  },
  _notifyStateChange: function PDFPresentationMode_notifyStateChange() {
   this.eventBus.dispatch('presentationmodechanged', {
    source: this,
    active: this.active,
    switchInProgress: !!this.switchInProgress
   });
  },
  _setSwitchInProgress: function PDFPresentationMode_setSwitchInProgress() {
   if (this.switchInProgress) {
    clearTimeout(this.switchInProgress);
   }
   this.switchInProgress = setTimeout(function switchInProgressTimeout() {
    this._removeFullscreenChangeListeners();
    delete this.switchInProgress;
    this._notifyStateChange();
   }.bind(this), DELAY_BEFORE_RESETTING_SWITCH_IN_PROGRESS);
  },
  _resetSwitchInProgress: function PDFPresentationMode_resetSwitchInProgress() {
   if (this.switchInProgress) {
    clearTimeout(this.switchInProgress);
    delete this.switchInProgress;
   }
  },
  _enter: function PDFPresentationMode_enter() {
   this.active = true;
   this._resetSwitchInProgress();
   this._notifyStateChange();
   this.container.classList.add(ACTIVE_SELECTOR);
   setTimeout(function enterPresentationModeTimeout() {
    this.pdfViewer.currentPageNumber = this.args.page;
    this.pdfViewer.currentScaleValue = 'page-fit';
   }.bind(this), 0);
   this._addWindowListeners();
   this._showControls();
   this.contextMenuOpen = false;
   this.container.setAttribute('contextmenu', 'viewerContextMenu');
   window.getSelection().removeAllRanges();
  },
  _exit: function PDFPresentationMode_exit() {
   var page = this.pdfViewer.currentPageNumber;
   this.container.classList.remove(ACTIVE_SELECTOR);
   setTimeout(function exitPresentationModeTimeout() {
    this.active = false;
    this._removeFullscreenChangeListeners();
    this._notifyStateChange();
    this.pdfViewer.currentScaleValue = this.args.previousScale;
    this.pdfViewer.currentPageNumber = page;
    this.args = null;
   }.bind(this), 0);
   this._removeWindowListeners();
   this._hideControls();
   this._resetMouseScrollState();
   this.container.removeAttribute('contextmenu');
   this.contextMenuOpen = false;
  },
  _mouseDown: function PDFPresentationMode_mouseDown(evt) {
   if (this.contextMenuOpen) {
    this.contextMenuOpen = false;
    evt.preventDefault();
    return;
   }
   if (evt.button === 0) {
    var isInternalLink = evt.target.href && evt.target.classList.contains('internalLink');
    if (!isInternalLink) {
     evt.preventDefault();
     this.pdfViewer.currentPageNumber += evt.shiftKey ? -1 : 1;
    }
   }
  },
  _contextMenu: function PDFPresentationMode_contextMenu() {
   this.contextMenuOpen = true;
  },
  _showControls: function PDFPresentationMode_showControls() {
   if (this.controlsTimeout) {
    clearTimeout(this.controlsTimeout);
   } else {
    this.container.classList.add(CONTROLS_SELECTOR);
   }
   this.controlsTimeout = setTimeout(function showControlsTimeout() {
    this.container.classList.remove(CONTROLS_SELECTOR);
    delete this.controlsTimeout;
   }.bind(this), DELAY_BEFORE_HIDING_CONTROLS);
  },
  _hideControls: function PDFPresentationMode_hideControls() {
   if (!this.controlsTimeout) {
    return;
   }
   clearTimeout(this.controlsTimeout);
   this.container.classList.remove(CONTROLS_SELECTOR);
   delete this.controlsTimeout;
  },
  _resetMouseScrollState: function PDFPresentationMode_resetMouseScrollState() {
   this.mouseScrollTimeStamp = 0;
   this.mouseScrollDelta = 0;
  },
  _touchSwipe: function PDFPresentationMode_touchSwipe(evt) {
   if (!this.active) {
    return;
   }
   var SWIPE_MIN_DISTANCE_THRESHOLD = 50;
   var SWIPE_ANGLE_THRESHOLD = Math.PI / 6;
   if (evt.touches.length > 1) {
    this.touchSwipeState = null;
    return;
   }
   switch (evt.type) {
   case 'touchstart':
    this.touchSwipeState = {
     startX: evt.touches[0].pageX,
     startY: evt.touches[0].pageY,
     endX: evt.touches[0].pageX,
     endY: evt.touches[0].pageY
    };
    break;
   case 'touchmove':
    if (this.touchSwipeState === null) {
     return;
    }
    this.touchSwipeState.endX = evt.touches[0].pageX;
    this.touchSwipeState.endY = evt.touches[0].pageY;
    evt.preventDefault();
    break;
   case 'touchend':
    if (this.touchSwipeState === null) {
     return;
    }
    var delta = 0;
    var dx = this.touchSwipeState.endX - this.touchSwipeState.startX;
    var dy = this.touchSwipeState.endY - this.touchSwipeState.startY;
    var absAngle = Math.abs(Math.atan2(dy, dx));
    if (Math.abs(dx) > SWIPE_MIN_DISTANCE_THRESHOLD && (absAngle <= SWIPE_ANGLE_THRESHOLD || absAngle >= Math.PI - SWIPE_ANGLE_THRESHOLD)) {
     delta = dx;
    } else if (Math.abs(dy) > SWIPE_MIN_DISTANCE_THRESHOLD && Math.abs(absAngle - Math.PI / 2) <= SWIPE_ANGLE_THRESHOLD) {
     delta = dy;
    }
    if (delta > 0) {
     this._goToPreviousPage();
    } else if (delta < 0) {
     this._goToNextPage();
    }
    break;
   }
  },
  _addWindowListeners: function PDFPresentationMode_addWindowListeners() {
   this.showControlsBind = this._showControls.bind(this);
   this.mouseDownBind = this._mouseDown.bind(this);
   this.mouseWheelBind = this._mouseWheel.bind(this);
   this.resetMouseScrollStateBind = this._resetMouseScrollState.bind(this);
   this.contextMenuBind = this._contextMenu.bind(this);
   this.touchSwipeBind = this._touchSwipe.bind(this);
   window.addEventListener('mousemove', this.showControlsBind);
   window.addEventListener('mousedown', this.mouseDownBind);
   window.addEventListener('wheel', this.mouseWheelBind);
   window.addEventListener('keydown', this.resetMouseScrollStateBind);
   window.addEventListener('contextmenu', this.contextMenuBind);
   window.addEventListener('touchstart', this.touchSwipeBind);
   window.addEventListener('touchmove', this.touchSwipeBind);
   window.addEventListener('touchend', this.touchSwipeBind);
  },
  _removeWindowListeners: function PDFPresentationMode_removeWindowListeners() {
   window.removeEventListener('mousemove', this.showControlsBind);
   window.removeEventListener('mousedown', this.mouseDownBind);
   window.removeEventListener('wheel', this.mouseWheelBind);
   window.removeEventListener('keydown', this.resetMouseScrollStateBind);
   window.removeEventListener('contextmenu', this.contextMenuBind);
   window.removeEventListener('touchstart', this.touchSwipeBind);
   window.removeEventListener('touchmove', this.touchSwipeBind);
   window.removeEventListener('touchend', this.touchSwipeBind);
   delete this.showControlsBind;
   delete this.mouseDownBind;
   delete this.mouseWheelBind;
   delete this.resetMouseScrollStateBind;
   delete this.contextMenuBind;
   delete this.touchSwipeBind;
  },
  _fullscreenChange: function PDFPresentationMode_fullscreenChange() {
   if (this.isFullscreen) {
    this._enter();
   } else {
    this._exit();
   }
  },
  _addFullscreenChangeListeners: function PDFPresentationMode_addFullscreenChangeListeners() {
   this.fullscreenChangeBind = this._fullscreenChange.bind(this);
   window.addEventListener('fullscreenchange', this.fullscreenChangeBind);
   window.addEventListener('mozfullscreenchange', this.fullscreenChangeBind);
   window.addEventListener('webkitfullscreenchange', this.fullscreenChangeBind);
   window.addEventListener('MSFullscreenChange', this.fullscreenChangeBind);
  },
  _removeFullscreenChangeListeners: function PDFPresentationMode_removeFullscreenChangeListeners() {
   window.removeEventListener('fullscreenchange', this.fullscreenChangeBind);
   window.removeEventListener('mozfullscreenchange', this.fullscreenChangeBind);
   window.removeEventListener('webkitfullscreenchange', this.fullscreenChangeBind);
   window.removeEventListener('MSFullscreenChange', this.fullscreenChangeBind);
   delete this.fullscreenChangeBind;
  }
 };
 return PDFPresentationMode;
}();
exports.PDFPresentationMode = PDFPresentationMode;