yomichan/ext/fg/js/text-source-range.js
toasted-nutbread 6f980d8f2b
Text source range refactor (#949)
* Rename functions for better clarity

* Remove unused properties

* Add getNodesInRange function

* Improve ignore nodes check

* Use private fields
2020-10-20 20:54:26 -04:00

159 lines
4.9 KiB
JavaScript

/*
* Copyright (C) 2016-2020 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
* DOMTextScanner
* DocumentUtil
*/
class TextSourceRange {
constructor(range, content, imposterContainer, imposterSourceElement) {
this._range = range;
this._rangeStartOffset = range.startOffset;
this._content = content;
this._imposterContainer = imposterContainer;
this._imposterSourceElement = imposterSourceElement;
}
get range() {
return this._range;
}
get rangeStartOffset() {
return this._rangeStartOffset;
}
get imposterSourceElement() {
return this._imposterSourceElement;
}
clone() {
return new TextSourceRange(this._range.cloneRange(), this._content, this._imposterContainer, this._imposterSourceElement);
}
cleanup() {
if (this._imposterContainer !== null && this._imposterContainer.parentNode !== null) {
this._imposterContainer.parentNode.removeChild(this._imposterContainer);
}
}
text() {
return this._content;
}
setEndOffset(length, layoutAwareScan, fromEnd=false) {
const state = (
fromEnd ?
new DOMTextScanner(this._range.endContainer, this._range.endOffset, !layoutAwareScan, layoutAwareScan).seek(length) :
new DOMTextScanner(this._range.startContainer, this._range.startOffset, !layoutAwareScan, layoutAwareScan).seek(length)
);
this._range.setEnd(state.node, state.offset);
this._content = (fromEnd ? this._content + state.content : state.content);
return length - state.remainder;
}
setStartOffset(length, layoutAwareScan) {
const state = new DOMTextScanner(this._range.startContainer, this._range.startOffset, !layoutAwareScan, layoutAwareScan).seek(-length);
this._range.setStart(state.node, state.offset);
this._rangeStartOffset = this._range.startOffset;
this._content = state.content + this._content;
return length - state.remainder;
}
getRect() {
return this._range.getBoundingClientRect();
}
getWritingMode() {
return TextSourceRange.getElementWritingMode(TextSourceRange.getParentElement(this._range.startContainer));
}
select() {
const selection = window.getSelection();
selection.removeAllRanges();
selection.addRange(this._range);
}
deselect() {
const selection = window.getSelection();
selection.removeAllRanges();
}
hasSameStart(other) {
if (!(
typeof other === 'object' &&
other !== null &&
other instanceof TextSourceRange
)) {
return false;
}
if (this._imposterSourceElement !== null) {
return (
this._imposterSourceElement === other.imposterSourceElement &&
this._rangeStartOffset === other.rangeStartOffset
);
} else {
try {
return this._range.compareBoundaryPoints(Range.START_TO_START, other.range) === 0;
} catch (e) {
if (e.name === 'WrongDocumentError') {
// This can happen with shadow DOMs if the ranges are in different documents.
return false;
}
throw e;
}
}
}
getNodesInRange() {
return DocumentUtil.getNodesInRange(this._range);
}
static getParentElement(node) {
while (node !== null && node.nodeType !== Node.ELEMENT_NODE) {
node = node.parentNode;
}
return node;
}
static getElementWritingMode(element) {
if (element !== null) {
const style = window.getComputedStyle(element);
const writingMode = style.writingMode;
if (typeof writingMode === 'string') {
return TextSourceRange.normalizeWritingMode(writingMode);
}
}
return 'horizontal-tb';
}
static normalizeWritingMode(writingMode) {
switch (writingMode) {
case 'lr':
case 'lr-tb':
case 'rl':
return 'horizontal-tb';
case 'tb':
return 'vertical-lr';
case 'tb-rl':
return 'vertical-rl';
default:
return writingMode;
}
}
}