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/*
* Beamer Viewer, a web-based PDF presentation viewer
* Copyright (C) 2018-2023 Pacien TRAN-GIRARD
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
"use strict";
class ActionEventHandler {
constructor(onNext, onPrevious) {
this.onNext = onNext;
this.onPrevious = onPrevious;
}
}
class KeyboardEventHandler extends ActionEventHandler {
register(window) {
window.addEventListener("keydown", event => this._onCommand(event));
}
_onCommand(keyboardEvent) {
switch (keyboardEvent.key) {
case "Enter":
case " ":
case "ArrowRight":
case "ArrowDown":
case "n":
return this.onNext();
case "ArrowLeft":
case "ArrowUp":
case "p":
return this.onPrevious();
}
}
}
class MouseClickEventHandler extends ActionEventHandler {
register(window) {
window.addEventListener("click", event => this._onCommand(event));
}
_onCommand(mouseEvent) {
this.onNext();
}
}
class TouchSwipeEventHandler extends ActionEventHandler {
constructor(onNext, onPrevious) {
super(onNext, onPrevious);
this.touchStartEvent = null;
this.touchMoveEvent = null;
}
register(window) {
window.addEventListener("touchstart", event => {
event.preventDefault();
this._onTouchStart(event);
});
window.addEventListener("touchmove", event => {
event.preventDefault();
this._onTouchMove(event);
});
window.addEventListener("touchend", event => {
event.preventDefault();
this._onTouchEnd();
});
window.addEventListener("touchcancel", event => {
event.preventDefault();
});
}
_onTouchStart(touchEvent) {
this.touchStartEvent = touchEvent;
}
_onTouchMove(touchEvent) {
this.touchMoveEvent = touchEvent;
}
_onTouchEnd() {
if (this.touchStartEvent == null || this.touchMoveEvent == null) return;
const touchDown = this._xCoordinate(this.touchStartEvent);
const touchUp = this._xCoordinate(this.touchMoveEvent);
const xDelta = touchDown - touchUp;
if (xDelta > 0)
this.onNext();
else if (xDelta < 0)
this.onPrevious();
this.touchStartEvent = null;
this.touchMoveEvent = null;
}
_xCoordinate(touchEvent) {
return touchEvent.touches[0].clientX; // first finger
}
}
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