yomichan/ext/mixed/js/text-scanner.js
toasted-nutbread e87cc5c37d
Query parser text scanner options refactor (#717)
* Add _setSelectedParser helper

* Update TextScanner internal options representation

* Update QueryParser internal options representation
2020-08-09 13:19:42 -04:00

420 lines
12 KiB
JavaScript

/*
* Copyright (C) 2019-2020 Yomichan Authors
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
/* global
* DOM
* docRangeFromPoint
*/
class TextScanner extends EventDispatcher {
constructor({node, ignoreElements, ignorePoint, search}) {
super();
this._node = node;
this._ignoreElements = ignoreElements;
this._ignorePoint = ignorePoint;
this._search = search;
this._isPrepared = false;
this._ignoreNodes = null;
this._causeCurrent = null;
this._scanTimerPromise = null;
this._textSourceCurrent = null;
this._textSourceCurrentSelected = false;
this._pendingLookup = false;
this._deepContentScan = false;
this._selectText = false;
this._modifier = 'none';
this._useMiddleMouse = false;
this._delay = 0;
this._touchInputEnabled = false;
this._enabled = false;
this._eventListeners = new EventListenerCollection();
this._primaryTouchIdentifier = null;
this._preventNextContextMenu = false;
this._preventNextMouseDown = false;
this._preventNextClick = false;
this._preventScroll = false;
this._canClearSelection = true;
}
get canClearSelection() {
return this._canClearSelection;
}
set canClearSelection(value) {
this._canClearSelection = value;
}
get ignoreNodes() {
return this._ignoreNodes;
}
set ignoreNodes(value) {
this._ignoreNodes = value;
}
get causeCurrent() {
return this._causeCurrent;
}
prepare() {
this._isPrepared = true;
this.setEnabled(this._enabled);
}
setEnabled(enabled) {
this._eventListeners.removeAllEventListeners();
this._enabled = enabled;
if (this._enabled && this._isPrepared) {
this._hookEvents();
} else {
this.clearSelection(true);
}
}
setOptions({deepContentScan, selectText, modifier, useMiddleMouse, delay, touchInputEnabled}) {
if (typeof deepContentScan === 'boolean') {
this._deepContentScan = deepContentScan;
}
if (typeof selectText === 'boolean') {
this._selectText = selectText;
}
if (typeof modifier === 'string') {
this._modifier = modifier;
}
if (typeof useMiddleMouse === 'boolean') {
this._useMiddleMouse = useMiddleMouse;
}
if (typeof delay === 'number') {
this._delay = delay;
}
if (typeof touchInputEnabled === 'boolean') {
this._touchInputEnabled = false;
}
}
async searchAt(x, y, cause) {
try {
this._scanTimerClear();
if (this._pendingLookup) {
return;
}
if (typeof this._ignorePoint === 'function' && await this._ignorePoint(x, y)) {
return;
}
const textSource = docRangeFromPoint(x, y, this._deepContentScan);
try {
if (this._textSourceCurrent !== null && this._textSourceCurrent.equals(textSource)) {
return;
}
this._pendingLookup = true;
const result = await this._search(textSource, cause);
if (result !== null) {
this._causeCurrent = cause;
this.setCurrentTextSource(textSource);
}
this._pendingLookup = false;
} finally {
if (textSource !== null) {
textSource.cleanup();
}
}
} catch (e) {
yomichan.logError(e);
}
}
getTextSourceContent(textSource, length, layoutAwareScan) {
const clonedTextSource = textSource.clone();
clonedTextSource.setEndOffset(length, layoutAwareScan);
if (this._ignoreNodes !== null && clonedTextSource.range) {
length = clonedTextSource.text().length;
while (clonedTextSource.range && length > 0) {
const nodes = DOM.getNodesInRange(clonedTextSource.range);
if (!DOM.anyNodeMatchesSelector(nodes, this._ignoreNodes)) {
break;
}
--length;
clonedTextSource.setEndOffset(length, layoutAwareScan);
}
}
return clonedTextSource.text();
}
clearSelection(passive) {
if (!this._canClearSelection) { return; }
if (this._textSourceCurrent !== null) {
if (this._textSourceCurrentSelected) {
this._textSourceCurrent.deselect();
}
this._textSourceCurrent = null;
this._textSourceCurrentSelected = false;
}
this.trigger('clearSelection', {passive});
}
getCurrentTextSource() {
return this._textSourceCurrent;
}
setCurrentTextSource(textSource) {
this._textSourceCurrent = textSource;
if (this._selectText) {
this._textSourceCurrent.select();
this._textSourceCurrentSelected = true;
} else {
this._textSourceCurrentSelected = false;
}
}
// Private
_onMouseOver(e) {
if (this._ignoreElements().includes(e.target)) {
this._scanTimerClear();
}
}
_onMouseMove(e) {
this._scanTimerClear();
if (this._pendingLookup || DOM.isMouseButtonDown(e, 'primary')) {
return;
}
const modifiers = DOM.getActiveModifiers(e);
this.trigger('activeModifiersChanged', {modifiers});
if (!(
this._isScanningModifierPressed(this._modifier, e) ||
(this._useMiddleMouse && DOM.isMouseButtonDown(e, 'auxiliary'))
)) {
return;
}
const search = async () => {
if (this._modifier === 'none') {
if (!await this._scanTimerWait()) {
// Aborted
return;
}
}
await this.searchAt(e.clientX, e.clientY, 'mouse');
};
search();
}
_onMouseDown(e) {
if (this._preventNextMouseDown) {
this._preventNextMouseDown = false;
this._preventNextClick = true;
e.preventDefault();
e.stopPropagation();
return false;
}
if (DOM.isMouseButtonDown(e, 'primary')) {
this._scanTimerClear();
this.clearSelection(false);
}
}
_onMouseOut() {
this._scanTimerClear();
}
_onClick(e) {
if (this._preventNextClick) {
this._preventNextClick = false;
e.preventDefault();
e.stopPropagation();
return false;
}
}
_onAuxClick() {
this._preventNextContextMenu = false;
}
_onContextMenu(e) {
if (this._preventNextContextMenu) {
this._preventNextContextMenu = false;
e.preventDefault();
e.stopPropagation();
return false;
}
}
_onTouchStart(e) {
if (this._primaryTouchIdentifier !== null || e.changedTouches.length === 0) {
return;
}
this._preventScroll = false;
this._preventNextContextMenu = false;
this._preventNextMouseDown = false;
this._preventNextClick = false;
const primaryTouch = e.changedTouches[0];
if (DOM.isPointInSelection(primaryTouch.clientX, primaryTouch.clientY, window.getSelection())) {
return;
}
this._primaryTouchIdentifier = primaryTouch.identifier;
if (this._pendingLookup) {
return;
}
const textSourceCurrentPrevious = this._textSourceCurrent !== null ? this._textSourceCurrent.clone() : null;
this.searchAt(primaryTouch.clientX, primaryTouch.clientY, 'touchStart')
.then(() => {
if (
this._textSourceCurrent === null ||
this._textSourceCurrent.equals(textSourceCurrentPrevious)
) {
return;
}
this._preventScroll = true;
this._preventNextContextMenu = true;
this._preventNextMouseDown = true;
});
}
_onTouchEnd(e) {
if (
this._primaryTouchIdentifier === null ||
this._getTouch(e.changedTouches, this._primaryTouchIdentifier) === null
) {
return;
}
this._primaryTouchIdentifier = null;
this._preventScroll = false;
this._preventNextClick = false;
// Don't revert context menu and mouse down prevention, since these events can occur after the touch has ended.
// I.e. this._preventNextContextMenu and this._preventNextMouseDown should not be assigned to false.
}
_onTouchCancel(e) {
this._onTouchEnd(e);
}
_onTouchMove(e) {
if (!this._preventScroll || !e.cancelable || this._primaryTouchIdentifier === null) {
return;
}
const primaryTouch = this._getTouch(e.changedTouches, this._primaryTouchIdentifier);
if (primaryTouch === null) {
return;
}
this.searchAt(primaryTouch.clientX, primaryTouch.clientY, 'touchMove');
e.preventDefault(); // Disable scroll
}
async _scanTimerWait() {
const delay = this._delay;
const promise = promiseTimeout(delay, true);
this._scanTimerPromise = promise;
try {
return await promise;
} finally {
if (this._scanTimerPromise === promise) {
this._scanTimerPromise = null;
}
}
}
_scanTimerClear() {
if (this._scanTimerPromise !== null) {
this._scanTimerPromise.resolve(false);
this._scanTimerPromise = null;
}
}
_hookEvents() {
const eventListenerInfos = this._getMouseEventListeners();
if (this._touchInputEnabled) {
eventListenerInfos.push(...this._getTouchEventListeners());
}
for (const [node, type, listener, options] of eventListenerInfos) {
this._eventListeners.addEventListener(node, type, listener, options);
}
}
_getMouseEventListeners() {
return [
[this._node, 'mousedown', this._onMouseDown.bind(this)],
[this._node, 'mousemove', this._onMouseMove.bind(this)],
[this._node, 'mouseover', this._onMouseOver.bind(this)],
[this._node, 'mouseout', this._onMouseOut.bind(this)]
];
}
_getTouchEventListeners() {
return [
[this._node, 'click', this._onClick.bind(this)],
[this._node, 'auxclick', this._onAuxClick.bind(this)],
[this._node, 'touchstart', this._onTouchStart.bind(this)],
[this._node, 'touchend', this._onTouchEnd.bind(this)],
[this._node, 'touchcancel', this._onTouchCancel.bind(this)],
[this._node, 'touchmove', this._onTouchMove.bind(this), {passive: false}],
[this._node, 'contextmenu', this._onContextMenu.bind(this)]
];
}
_isScanningModifierPressed(scanningModifier, mouseEvent) {
switch (scanningModifier) {
case 'alt': return mouseEvent.altKey;
case 'ctrl': return mouseEvent.ctrlKey;
case 'shift': return mouseEvent.shiftKey;
case 'meta': return mouseEvent.metaKey;
case 'none': return true;
default: return false;
}
}
_getTouch(touchList, identifier) {
for (const touch of touchList) {
if (touch.identifier === identifier) {
return touch;
}
}
return null;
}
}