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authortoasted-nutbread <toasted-nutbread@users.noreply.github.com>2024-02-02 21:56:59 -0500
committerGitHub <noreply@github.com>2024-02-03 02:56:59 +0000
commit17ffea6cb907c12c1af47d3f6f27126f126b168f (patch)
tree2c350b999c7271387ac3466583f71411f6be13c9 /ext/js/dom/text-source-generator.js
parentc4f248b0f95050fb373c898289b506d042a3731b (diff)
Text source generator function move (#611)
* Move functionality into TextSourceGenerator * Move extractSentence * Move isWhitespace
Diffstat (limited to 'ext/js/dom/text-source-generator.js')
-rw-r--r--ext/js/dom/text-source-generator.js601
1 files changed, 600 insertions, 1 deletions
diff --git a/ext/js/dom/text-source-generator.js b/ext/js/dom/text-source-generator.js
index 0435e69b..a5529779 100644
--- a/ext/js/dom/text-source-generator.js
+++ b/ext/js/dom/text-source-generator.js
@@ -16,9 +16,14 @@
*/
import {DocumentUtil} from './document-util.js';
+import {DOMTextScanner} from './dom-text-scanner.js';
+import {TextSourceElement} from './text-source-element.js';
+import {TextSourceRange} from './text-source-range.js';
export class TextSourceGenerator {
constructor() {
+ /** @type {RegExp} @readonly */
+ this._transparentColorPattern = /rgba\s*\([^)]*,\s*0(?:\.0+)?\s*\)/;
/** @type {import('text-source-generator').GetRangeFromPointHandler[]} @readonly */
this._getRangeFromPointHandlers = [];
}
@@ -34,7 +39,7 @@ export class TextSourceGenerator {
const result = handler(x, y, options);
if (result !== null) { return result; }
}
- return DocumentUtil.getRangeFromPoint(x, y, options);
+ return this._getRangeFromPointInternal(x, y, options);
}
/**
@@ -44,4 +49,598 @@ export class TextSourceGenerator {
registerGetRangeFromPointHandler(handler) {
this._getRangeFromPointHandlers.push(handler);
}
+
+ /**
+ * Extract a sentence from a document.
+ * @param {import('text-source').TextSource} source The text source object, either `TextSourceRange` or `TextSourceElement`.
+ * @param {boolean} layoutAwareScan Whether or not layout-aware scan mode should be used.
+ * @param {number} extent The length of the sentence to extract.
+ * @param {boolean} terminateAtNewlines Whether or not a sentence should be terminated at newline characters.
+ * @param {import('text-scanner').SentenceTerminatorMap} terminatorMap A mapping of characters that terminate a sentence.
+ * @param {import('text-scanner').SentenceForwardQuoteMap} forwardQuoteMap A mapping of quote characters that delimit a sentence.
+ * @param {import('text-scanner').SentenceBackwardQuoteMap} backwardQuoteMap A mapping of quote characters that delimit a sentence, which is the inverse of forwardQuoteMap.
+ * @returns {{text: string, offset: number}} The sentence and the offset to the original source.
+ */
+ 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, true, layoutAwareScan);
+ const text = source.text();
+ const textLength = text.length;
+ const textEndAnchor = textLength - endLength;
+
+ /** Relative start position of the sentence (inclusive). */
+ let cursorStart = startLength;
+ /** Relative end position of the sentence (exclusive). */
+ let cursorEnd = textEndAnchor;
+
+ // Move backward
+ let quoteStack = [];
+ for (; cursorStart > 0; --cursorStart) {
+ // Check if the previous character should be included.
+ let c = text[cursorStart - 1];
+ if (c === '\n' && terminateAtNewlines) { break; }
+
+ if (quoteStack.length === 0) {
+ let terminatorInfo = terminatorMap.get(c);
+ if (typeof terminatorInfo !== 'undefined') {
+ // Include the previous character while it is a terminator character and is included at start.
+ while (terminatorInfo[0] && cursorStart > 0) {
+ --cursorStart;
+ if (cursorStart === 0) { break; }
+ c = text[cursorStart - 1];
+ terminatorInfo = terminatorMap.get(c);
+ if (typeof terminatorInfo === 'undefined') { break; }
+ }
+ break;
+ }
+ }
+
+ let quoteInfo = forwardQuoteMap.get(c);
+ if (typeof quoteInfo !== 'undefined') {
+ if (quoteStack.length === 0) {
+ // Include the previous character while it is a quote character and is included at start.
+ while (quoteInfo[1] && cursorStart > 0) {
+ --cursorStart;
+ if (cursorStart === 0) { break; }
+ c = text[cursorStart - 1];
+ quoteInfo = forwardQuoteMap.get(c);
+ if (typeof quoteInfo === 'undefined') { break; }
+ }
+ 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 (; cursorEnd < textLength; ++cursorEnd) {
+ // Check if the following character should be included.
+ let c = text[cursorEnd];
+ if (c === '\n' && terminateAtNewlines) { break; }
+
+ if (quoteStack.length === 0) {
+ let terminatorInfo = terminatorMap.get(c);
+ if (typeof terminatorInfo !== 'undefined') {
+ // Include the following character while it is a terminator character and is included at end.
+ while (terminatorInfo[1] && cursorEnd < textLength) {
+ ++cursorEnd;
+ if (cursorEnd === textLength) { break; }
+ c = text[cursorEnd];
+ terminatorInfo = terminatorMap.get(c);
+ if (typeof terminatorInfo === 'undefined') { break; }
+ }
+ break;
+ }
+ }
+
+ let quoteInfo = backwardQuoteMap.get(c);
+ if (typeof quoteInfo !== 'undefined') {
+ if (quoteStack.length === 0) {
+ // Include the following character while it is a quote character and is included at end.
+ while (quoteInfo[1] && cursorEnd < textLength) {
+ ++cursorEnd;
+ if (cursorEnd === textLength) { break; }
+ c = text[cursorEnd];
+ quoteInfo = forwardQuoteMap.get(c);
+ if (typeof quoteInfo === 'undefined') { break; }
+ }
+ break;
+ } else if (quoteStack[0] === c) {
+ quoteStack.pop();
+ continue;
+ }
+ }
+
+ quoteInfo = forwardQuoteMap.get(c);
+ if (typeof quoteInfo !== 'undefined') {
+ quoteStack.unshift(quoteInfo[0]);
+ }
+ }
+
+ // Trim whitespace
+ for (; cursorStart < startLength && this._isWhitespace(text[cursorStart]); ++cursorStart) { /* NOP */ }
+ for (; cursorEnd > textEndAnchor && this._isWhitespace(text[cursorEnd - 1]); --cursorEnd) { /* NOP */ }
+
+ // Result
+ return {
+ text: text.substring(cursorStart, cursorEnd),
+ offset: startLength - cursorStart
+ };
+ }
+
+ /**
+ * Scans the document for text or elements with text information at the given coordinate.
+ * Coordinates are provided in [client space](https://developer.mozilla.org/en-US/docs/Web/CSS/CSSOM_View/Coordinate_systems).
+ * @param {number} x The x coordinate to search at.
+ * @param {number} y The y coordinate to search at.
+ * @param {import('document-util').GetRangeFromPointOptions} options Options to configure how element detection is performed.
+ * @returns {?import('text-source').TextSource} A range for the hovered text or element, or `null` if no applicable content was found.
+ */
+ _getRangeFromPointInternal(x, y, options) {
+ const {deepContentScan, normalizeCssZoom} = options;
+
+ const elements = this._getElementsFromPoint(x, y, deepContentScan);
+ /** @type {?HTMLDivElement} */
+ let imposter = null;
+ /** @type {?HTMLDivElement} */
+ let imposterContainer = null;
+ /** @type {?Element} */
+ let imposterSourceElement = null;
+ if (elements.length > 0) {
+ const element = elements[0];
+ switch (element.nodeName.toUpperCase()) {
+ case 'IMG':
+ case 'BUTTON':
+ case 'SELECT':
+ return TextSourceElement.create(element);
+ case 'INPUT':
+ if (/** @type {HTMLInputElement} */ (element).type === 'text') {
+ imposterSourceElement = element;
+ [imposter, imposterContainer] = this._createImposter(/** @type {HTMLInputElement} */ (element), false);
+ }
+ break;
+ case 'TEXTAREA':
+ imposterSourceElement = element;
+ [imposter, imposterContainer] = this._createImposter(/** @type {HTMLTextAreaElement} */ (element), true);
+ break;
+ }
+ }
+
+ const range = this._caretRangeFromPointExt(x, y, deepContentScan ? elements : [], normalizeCssZoom);
+ if (range !== null) {
+ if (imposter !== null) {
+ this._setImposterStyle(/** @type {HTMLDivElement} */ (imposterContainer).style, 'z-index', '-2147483646');
+ this._setImposterStyle(imposter.style, 'pointer-events', 'none');
+ return TextSourceRange.createFromImposter(range, /** @type {HTMLDivElement} */ (imposterContainer), /** @type {HTMLElement} */ (imposterSourceElement));
+ }
+ return TextSourceRange.create(range);
+ } else {
+ if (imposterContainer !== null) {
+ const {parentNode} = imposterContainer;
+ if (parentNode !== null) {
+ parentNode.removeChild(imposterContainer);
+ }
+ }
+ return null;
+ }
+ }
+
+ /**
+ * @param {CSSStyleDeclaration} style
+ * @param {string} propertyName
+ * @param {string} value
+ */
+ _setImposterStyle(style, propertyName, value) {
+ style.setProperty(propertyName, value, 'important');
+ }
+
+ /**
+ * @param {HTMLInputElement|HTMLTextAreaElement} element
+ * @param {boolean} isTextarea
+ * @returns {[imposter: ?HTMLDivElement, container: ?HTMLDivElement]}
+ */
+ _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];
+ }
+
+ /**
+ * @param {number} x
+ * @param {number} y
+ * @param {boolean} all
+ * @returns {Element[]}
+ */
+ _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] : [];
+ }
+
+ /**
+ * @param {number} x
+ * @param {number} y
+ * @param {Range} range
+ * @param {boolean} normalizeCssZoom
+ * @returns {boolean}
+ */
+ _isPointInRange(x, y, range, normalizeCssZoom) {
+ // Require a text node to start
+ const {startContainer} = range;
+ if (startContainer.nodeType !== Node.TEXT_NODE) {
+ return false;
+ }
+
+ // Convert CSS zoom coordinates
+ if (normalizeCssZoom) {
+ const scale = DocumentUtil.computeZoomScale(startContainer);
+ x /= scale;
+ y /= scale;
+ }
+
+ // Scan forward
+ const nodePre = range.endContainer;
+ const offsetPre = range.endOffset;
+ try {
+ const {node, offset, content} = new DOMTextScanner(nodePre, offsetPre, 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(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;
+ }
+
+ /**
+ * @param {number} x
+ * @param {number} y
+ * @returns {?Range}
+ */
+ _caretRangeFromPoint(x, y) {
+ if (typeof document.caretRangeFromPoint === 'function') {
+ // Chrome, Edge
+ return document.caretRangeFromPoint(x, y);
+ }
+
+ // @ts-expect-error - caretPositionFromPoint is non-standard
+ if (typeof document.caretPositionFromPoint === 'function') {
+ // Firefox
+ return this._caretPositionFromPoint(x, y);
+ }
+
+ // No support
+ return null;
+ }
+
+ /**
+ * @param {number} x
+ * @param {number} y
+ * @returns {?Range}
+ */
+ _caretPositionFromPoint(x, y) {
+ // @ts-expect-error - caretPositionFromPoint is non-standard
+ const position = /** @type {(x: number, y: number) => ?{offsetNode: Node, offset: number}} */ (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(/** @type {Element} */ (node))) {
+ return this._caretPositionFromPointNormalizeStyles(x, y, /** @type {Element} */ (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;
+ }
+ }
+
+ /**
+ * @param {number} x
+ * @param {number} y
+ * @param {Element} nextElement
+ * @returns {?Range}
+ */
+ _caretPositionFromPointNormalizeStyles(x, y, nextElement) {
+ const previousStyles = new Map();
+ try {
+ while (true) {
+ if (nextElement instanceof HTMLElement) {
+ this._recordPreviousStyle(previousStyles, nextElement);
+ nextElement.style.setProperty('user-select', 'text', 'important');
+ }
+
+ // @ts-expect-error - caretPositionFromPoint is non-standard
+ const position = /** @type {(x: number, y: number) => ?{offsetNode: Node, offset: number}} */ (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(/** @type {Element} */ (node))) {
+ if (previousStyles.has(node)) {
+ // Recursive
+ return null;
+ }
+ nextElement = /** @type {Element} */ (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);
+ }
+ }
+
+ /**
+ * @param {number} x
+ * @param {number} y
+ * @param {Element[]} elements
+ * @param {boolean} normalizeCssZoom
+ * @returns {?Range}
+ */
+ _caretRangeFromPointExt(x, y, elements, normalizeCssZoom) {
+ 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, normalizeCssZoom)) {
+ 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);
+ }
+ }
+ }
+
+ /**
+ * @param {Element[]} elements
+ * @param {number} i
+ * @param {Map<Element, ?string>} previousStyles
+ * @returns {number}
+ */
+ _disableTransparentElement(elements, i, previousStyles) {
+ while (true) {
+ if (i >= elements.length) {
+ return -1;
+ }
+
+ const element = elements[i++];
+ if (this._isElementTransparent(element)) {
+ if (element instanceof HTMLElement) {
+ this._recordPreviousStyle(previousStyles, element);
+ element.style.setProperty('pointer-events', 'none', 'important');
+ }
+ return i;
+ }
+ }
+ }
+
+ /**
+ * @param {Map<Element, ?string>} previousStyles
+ * @param {Element} element
+ */
+ _recordPreviousStyle(previousStyles, element) {
+ if (previousStyles.has(element)) { return; }
+ const style = element.hasAttribute('style') ? element.getAttribute('style') : null;
+ previousStyles.set(element, style);
+ }
+
+ /**
+ * @param {Map<Element, ?string>} previousStyles
+ */
+ _revertStyles(previousStyles) {
+ for (const [element, style] of previousStyles.entries()) {
+ if (style === null) {
+ element.removeAttribute('style');
+ } else {
+ element.setAttribute('style', style);
+ }
+ }
+ }
+
+ /**
+ * @param {Element} element
+ * @returns {boolean}
+ */
+ _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))
+ );
+ }
+
+ /**
+ * @param {string} cssColor
+ * @returns {boolean}
+ */
+ _isColorTransparent(cssColor) {
+ return this._transparentColorPattern.test(cssColor);
+ }
+
+ /**
+ * @param {Element} element
+ * @returns {boolean}
+ */
+ _isElementUserSelectAll(element) {
+ return getComputedStyle(element).userSelect === 'all';
+ }
+
+ /**
+ * @param {string} string
+ * @returns {boolean}
+ */
+ _isWhitespace(string) {
+ return string.trim().length === 0;
+ }
}