yomichan/ext/js/dom/document-util.js

665 lines
23 KiB
JavaScript

/*
* Copyright (C) 2016-2021 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
* DOMTextScanner
* TextSourceElement
* TextSourceRange
*/
class DocumentUtil {
constructor() {
this._transparentColorPattern = /rgba\s*\([^)]*,\s*0(?:\.0+)?\s*\)/;
}
getRangeFromPoint(x, y, deepContentScan) {
const elements = this._getElementsFromPoint(x, y, deepContentScan);
let imposter = null;
let imposterContainer = null;
let imposterSourceElement = null;
if (elements.length > 0) {
const element = elements[0];
switch (element.nodeName.toUpperCase()) {
case 'IMG':
case 'BUTTON':
case 'SELECT':
return new TextSourceElement(element);
case 'INPUT':
if (element.type === 'text') {
imposterSourceElement = element;
[imposter, imposterContainer] = this._createImposter(element, false);
}
break;
case 'TEXTAREA':
imposterSourceElement = element;
[imposter, imposterContainer] = this._createImposter(element, true);
break;
}
}
const range = this._caretRangeFromPointExt(x, y, deepContentScan ? elements : []);
if (range !== null) {
if (imposter !== null) {
this._setImposterStyle(imposterContainer.style, 'z-index', '-2147483646');
this._setImposterStyle(imposter.style, 'pointer-events', 'none');
}
return new TextSourceRange(range, '', imposterContainer, imposterSourceElement);
} else {
if (imposterContainer !== null) {
imposterContainer.parentNode.removeChild(imposterContainer);
}
return null;
}
}
/**
* Extract a sentence from a document.
* @param source The text source object, either `TextSourceRange` or `TextSourceElement`.
* @param layoutAwareScan Whether or not layout-aware scan mode should be used.
* @param extent The length of the sentence to extract.
* @param terminateAtNewlines Whether or not a sentence should be terminated at newline characters.
* @param terminatorMap A mapping of characters that terminate a sentence.
* Format:
* ```js
* new Map([ [character: string, [includeCharacterAtStart: boolean, includeCharacterAtEnd: boolean]], ... ])
* ```
* @param forwardQuoteMap A mapping of quote characters that delimit a sentence.
* Format:
* ```js
* new Map([ [character: string, [otherCharacter: string, includeCharacterAtStart: boolean]], ... ])
* ```
* @param backwardQuoteMap A mapping of quote characters that delimit a sentence,
* which is the inverse of forwardQuoteMap.
* Format:
* ```js
* new Map([ [character: string, [otherCharacter: string, includeCharacterAtEnd: boolean]], ... ])
* ```
* @returns The sentence and the offset to the original source: `{sentence: string, offset: integer}`.
*/
extractSentence(source, layoutAwareScan, extent, terminateAtNewlines, terminatorMap, forwardQuoteMap, backwardQuoteMap) {
// Scan text
source = source.clone();
const startLength = source.setStartOffset(extent, layoutAwareScan);
const endLength = source.setEndOffset(extent * 2 - startLength, layoutAwareScan, true);
const text = source.text();
const textLength = text.length;
const textEndAnchor = textLength - endLength;
let pos1 = startLength;
let pos2 = textEndAnchor;
// Move backward
let quoteStack = [];
for (; pos1 > 0; --pos1) {
const c = text[pos1 - 1];
if (c === '\n' && terminateAtNewlines) { break; }
if (quoteStack.length === 0) {
const terminatorInfo = terminatorMap.get(c);
if (typeof terminatorInfo !== 'undefined') {
if (terminatorInfo[0]) { --pos1; }
break;
}
}
let quoteInfo = forwardQuoteMap.get(c);
if (typeof quoteInfo !== 'undefined') {
if (quoteStack.length === 0) {
if (quoteInfo[1]) { --pos1; }
break;
} else if (quoteStack[0] === c) {
quoteStack.pop();
continue;
}
}
quoteInfo = backwardQuoteMap.get(c);
if (typeof quoteInfo !== 'undefined') {
quoteStack.unshift(quoteInfo[0]);
}
}
// Move forward
quoteStack = [];
for (; pos2 < textLength; ++pos2) {
const c = text[pos2];
if (c === '\n' && terminateAtNewlines) { break; }
if (quoteStack.length === 0) {
const terminatorInfo = terminatorMap.get(c);
if (typeof terminatorInfo !== 'undefined') {
if (terminatorInfo[1]) { ++pos2; }
break;
}
}
let quoteInfo = backwardQuoteMap.get(c);
if (typeof quoteInfo !== 'undefined') {
if (quoteStack.length === 0) {
if (quoteInfo[1]) { ++pos2; }
break;
} else if (quoteStack[0] === c) {
quoteStack.pop();
continue;
}
}
quoteInfo = forwardQuoteMap.get(c);
if (typeof quoteInfo !== 'undefined') {
quoteStack.unshift(quoteInfo[0]);
}
}
// Trim whitespace
for (; pos1 < startLength && this._isWhitespace(text[pos1]); ++pos1) { /* NOP */ }
for (; pos2 > textEndAnchor && this._isWhitespace(text[pos2 - 1]); --pos2) { /* NOP */ }
// Result
return {
text: text.substring(pos1, pos2),
offset: startLength - pos1
};
}
static isPointInRect(x, y, rect) {
return (
x >= rect.left && x < rect.right &&
y >= rect.top && y < rect.bottom
);
}
static isPointInAnyRect(x, y, rects) {
for (const rect of rects) {
if (this.isPointInRect(x, y, rect)) {
return true;
}
}
return false;
}
static isPointInSelection(x, y, selection) {
for (let i = 0; i < selection.rangeCount; ++i) {
const range = selection.getRangeAt(i);
if (this.isPointInAnyRect(x, y, range.getClientRects())) {
return true;
}
}
return false;
}
static isMouseButtonPressed(mouseEvent, button) {
const mouseEventButton = mouseEvent.button;
switch (button) {
case 'primary': return mouseEventButton === 0;
case 'secondary': return mouseEventButton === 2;
case 'auxiliary': return mouseEventButton === 1;
default: return false;
}
}
static getActiveModifiers(event) {
const modifiers = [];
if (event.altKey) { modifiers.push('alt'); }
if (event.ctrlKey) { modifiers.push('ctrl'); }
if (event.metaKey) { modifiers.push('meta'); }
if (event.shiftKey) { modifiers.push('shift'); }
return modifiers;
}
static getActiveModifiersAndButtons(event) {
const modifiers = this.getActiveModifiers(event);
this._getActiveButtons(event, modifiers);
return modifiers;
}
static getActiveButtons(event) {
const buttons = [];
this._getActiveButtons(event, buttons);
return buttons;
}
static addFullscreenChangeEventListener(onFullscreenChanged, eventListenerCollection=null) {
const target = document;
const options = false;
const fullscreenEventNames = [
'fullscreenchange',
'MSFullscreenChange',
'mozfullscreenchange',
'webkitfullscreenchange'
];
for (const eventName of fullscreenEventNames) {
if (eventListenerCollection === null) {
target.addEventListener(eventName, onFullscreenChanged, options);
} else {
eventListenerCollection.addEventListener(target, eventName, onFullscreenChanged, options);
}
}
}
static getFullscreenElement() {
return (
document.fullscreenElement ||
document.msFullscreenElement ||
document.mozFullScreenElement ||
document.webkitFullscreenElement ||
null
);
}
static getNodesInRange(range) {
const end = range.endContainer;
const nodes = [];
for (let node = range.startContainer; node !== null; node = this.getNextNode(node)) {
nodes.push(node);
if (node === end) { break; }
}
return nodes;
}
static getNextNode(node) {
let next = node.firstChild;
if (next === null) {
while (true) {
next = node.nextSibling;
if (next !== null) { break; }
next = node.parentNode;
if (next === null) { break; }
node = next;
}
}
return next;
}
static anyNodeMatchesSelector(nodes, selector) {
const ELEMENT_NODE = Node.ELEMENT_NODE;
for (let node of nodes) {
for (; node !== null; node = node.parentNode) {
if (node.nodeType !== ELEMENT_NODE) { continue; }
if (node.matches(selector)) { return true; }
break;
}
}
return false;
}
static everyNodeMatchesSelector(nodes, selector) {
const ELEMENT_NODE = Node.ELEMENT_NODE;
for (let node of nodes) {
while (true) {
if (node === null) { return false; }
if (node.nodeType === ELEMENT_NODE && node.matches(selector)) { break; }
node = node.parentNode;
}
}
return true;
}
static isMetaKeySupported(os, browser) {
return !(browser === 'firefox' || browser === 'firefox-mobile') || os === 'mac';
}
static isInputElementFocused() {
const element = document.activeElement;
if (element === null) { return false; }
const type = element.nodeName.toUpperCase();
switch (type) {
case 'INPUT':
case 'TEXTAREA':
case 'SELECT':
return true;
default:
return element.isContentEditable;
}
}
// Private
static _getActiveButtons(event, array) {
let {buttons} = event;
if (typeof buttons === 'number' && buttons > 0) {
for (let i = 0; i < 6; ++i) {
const buttonFlag = (1 << i);
if ((buttons & buttonFlag) !== 0) {
array.push(`mouse${i}`);
buttons &= ~buttonFlag;
if (buttons === 0) { break; }
}
}
}
}
_setImposterStyle(style, propertyName, value) {
style.setProperty(propertyName, value, 'important');
}
_createImposter(element, isTextarea) {
const body = document.body;
if (body === null) { return [null, null]; }
const elementStyle = window.getComputedStyle(element);
const elementRect = element.getBoundingClientRect();
const documentRect = document.documentElement.getBoundingClientRect();
let left = elementRect.left - documentRect.left;
let top = elementRect.top - documentRect.top;
// Container
const container = document.createElement('div');
const containerStyle = container.style;
this._setImposterStyle(containerStyle, 'all', 'initial');
this._setImposterStyle(containerStyle, 'position', 'absolute');
this._setImposterStyle(containerStyle, 'left', '0');
this._setImposterStyle(containerStyle, 'top', '0');
this._setImposterStyle(containerStyle, 'width', `${documentRect.width}px`);
this._setImposterStyle(containerStyle, 'height', `${documentRect.height}px`);
this._setImposterStyle(containerStyle, 'overflow', 'hidden');
this._setImposterStyle(containerStyle, 'opacity', '0');
this._setImposterStyle(containerStyle, 'pointer-events', 'none');
this._setImposterStyle(containerStyle, 'z-index', '2147483646');
// Imposter
const imposter = document.createElement('div');
const imposterStyle = imposter.style;
let value = element.value;
if (value.endsWith('\n')) { value += '\n'; }
imposter.textContent = value;
for (let i = 0, ii = elementStyle.length; i < ii; ++i) {
const property = elementStyle[i];
this._setImposterStyle(imposterStyle, property, elementStyle.getPropertyValue(property));
}
this._setImposterStyle(imposterStyle, 'position', 'absolute');
this._setImposterStyle(imposterStyle, 'top', `${top}px`);
this._setImposterStyle(imposterStyle, 'left', `${left}px`);
this._setImposterStyle(imposterStyle, 'margin', '0');
this._setImposterStyle(imposterStyle, 'pointer-events', 'auto');
if (isTextarea) {
if (elementStyle.overflow === 'visible') {
this._setImposterStyle(imposterStyle, 'overflow', 'auto');
}
} else {
this._setImposterStyle(imposterStyle, 'overflow', 'hidden');
this._setImposterStyle(imposterStyle, 'white-space', 'nowrap');
this._setImposterStyle(imposterStyle, 'line-height', elementStyle.height);
}
container.appendChild(imposter);
body.appendChild(container);
// Adjust size
const imposterRect = imposter.getBoundingClientRect();
if (imposterRect.width !== elementRect.width || imposterRect.height !== elementRect.height) {
const width = parseFloat(elementStyle.width) + (elementRect.width - imposterRect.width);
const height = parseFloat(elementStyle.height) + (elementRect.height - imposterRect.height);
this._setImposterStyle(imposterStyle, 'width', `${width}px`);
this._setImposterStyle(imposterStyle, 'height', `${height}px`);
}
if (imposterRect.left !== elementRect.left || imposterRect.top !== elementRect.top) {
left += (elementRect.left - imposterRect.left);
top += (elementRect.top - imposterRect.top);
this._setImposterStyle(imposterStyle, 'left', `${left}px`);
this._setImposterStyle(imposterStyle, 'top', `${top}px`);
}
imposter.scrollTop = element.scrollTop;
imposter.scrollLeft = element.scrollLeft;
return [imposter, container];
}
_getElementsFromPoint(x, y, all) {
if (all) {
// document.elementsFromPoint can return duplicates which must be removed.
const elements = document.elementsFromPoint(x, y);
return elements.filter((e, i) => elements.indexOf(e) === i);
}
const e = document.elementFromPoint(x, y);
return e !== null ? [e] : [];
}
_isPointInRange(x, y, range) {
// Require a text node to start
if (range.startContainer.nodeType !== Node.TEXT_NODE) {
return false;
}
// Scan forward
const nodePre = range.endContainer;
const offsetPre = range.endOffset;
try {
const {node, offset, content} = new DOMTextScanner(range.endContainer, range.endOffset, true, false).seek(1);
range.setEnd(node, offset);
if (!this._isWhitespace(content) && DocumentUtil.isPointInAnyRect(x, y, range.getClientRects())) {
return true;
}
} finally {
range.setEnd(nodePre, offsetPre);
}
// Scan backward
const {node, offset, content} = new DOMTextScanner(range.startContainer, range.startOffset, true, false).seek(-1);
range.setStart(node, offset);
if (!this._isWhitespace(content) && DocumentUtil.isPointInAnyRect(x, y, range.getClientRects())) {
// This purposefully leaves the starting offset as modified and sets the range length to 0.
range.setEnd(node, offset);
return true;
}
// No match
return false;
}
_isWhitespace(string) {
return string.trim().length === 0;
}
_caretRangeFromPoint(x, y) {
if (typeof document.caretRangeFromPoint === 'function') {
// Chrome, Edge
return document.caretRangeFromPoint(x, y);
}
if (typeof document.caretPositionFromPoint === 'function') {
// Firefox
return this._caretPositionFromPoint(x, y);
}
// No support
return null;
}
_caretPositionFromPoint(x, y) {
const position = document.caretPositionFromPoint(x, y);
if (position === null) {
return null;
}
const node = position.offsetNode;
if (node === null) {
return null;
}
let offset = 0;
const {nodeType} = node;
switch (nodeType) {
case Node.TEXT_NODE:
offset = position.offset;
break;
case Node.ELEMENT_NODE:
// Elements with user-select: all will return the element
// instead of a text point inside the element.
if (this._isElementUserSelectAll(node)) {
return this._caretPositionFromPointNormalizeStyles(x, y, node);
}
break;
}
try {
const range = document.createRange();
range.setStart(node, offset);
range.setEnd(node, offset);
return range;
} catch (e) {
// Firefox throws new DOMException("The operation is insecure.")
// when trying to select a node from within a ShadowRoot.
return null;
}
}
_caretPositionFromPointNormalizeStyles(x, y, nextElement) {
const previousStyles = new Map();
try {
while (true) {
this._recordPreviousStyle(previousStyles, nextElement);
nextElement.style.setProperty('user-select', 'text', 'important');
const position = document.caretPositionFromPoint(x, y);
if (position === null) {
return null;
}
const node = position.offsetNode;
if (node === null) {
return null;
}
let offset = 0;
const {nodeType} = node;
switch (nodeType) {
case Node.TEXT_NODE:
offset = position.offset;
break;
case Node.ELEMENT_NODE:
// Elements with user-select: all will return the element
// instead of a text point inside the element.
if (this._isElementUserSelectAll(node)) {
if (previousStyles.has(node)) {
// Recursive
return null;
}
nextElement = node;
continue;
}
break;
}
try {
const range = document.createRange();
range.setStart(node, offset);
range.setEnd(node, offset);
return range;
} catch (e) {
// Firefox throws new DOMException("The operation is insecure.")
// when trying to select a node from within a ShadowRoot.
return null;
}
}
} finally {
this._revertStyles(previousStyles);
}
}
_caretRangeFromPointExt(x, y, elements) {
let previousStyles = null;
try {
let i = 0;
let startContinerPre = null;
while (true) {
const range = this._caretRangeFromPoint(x, y);
if (range === null) {
return null;
}
const startContainer = range.startContainer;
if (startContinerPre !== startContainer) {
if (this._isPointInRange(x, y, range)) {
return range;
}
startContinerPre = startContainer;
}
if (previousStyles === null) { previousStyles = new Map(); }
i = this._disableTransparentElement(elements, i, previousStyles);
if (i < 0) {
return null;
}
}
} finally {
if (previousStyles !== null && previousStyles.size > 0) {
this._revertStyles(previousStyles);
}
}
}
_disableTransparentElement(elements, i, previousStyles) {
while (true) {
if (i >= elements.length) {
return -1;
}
const element = elements[i++];
if (this._isElementTransparent(element)) {
this._recordPreviousStyle(previousStyles, element);
element.style.setProperty('pointer-events', 'none', 'important');
return i;
}
}
}
_recordPreviousStyle(previousStyles, element) {
if (previousStyles.has(element)) { return; }
const style = element.hasAttribute('style') ? element.getAttribute('style') : null;
previousStyles.set(element, style);
}
_revertStyles(previousStyles) {
for (const [element, style] of previousStyles.entries()) {
if (style === null) {
element.removeAttribute('style');
} else {
element.setAttribute('style', style);
}
}
}
_isElementTransparent(element) {
if (
element === document.body ||
element === document.documentElement
) {
return false;
}
const style = window.getComputedStyle(element);
return (
parseFloat(style.opacity) <= 0 ||
style.visibility === 'hidden' ||
(style.backgroundImage === 'none' && this._isColorTransparent(style.backgroundColor))
);
}
_isColorTransparent(cssColor) {
return this._transparentColorPattern.test(cssColor);
}
_isElementUserSelectAll(element) {
return getComputedStyle(element).userSelect === 'all';
}
}