/* * 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': 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 _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${i}`); buttons &= ~buttonFlag; if (buttons === 0) { break; } } } } } // Private _setImposterStyle(style, propertyName, value) { style.setProperty(propertyName, value, 'important'); } _createImposter(element, isTextarea) { const body = document.body; if (body === null) { return [null, null]; } const elementStyle = window.getComputedStyle(element); const elementRect = element.getBoundingClientRect(); const documentRect = document.documentElement.getBoundingClientRect(); let left = elementRect.left - documentRect.left; let top = elementRect.top - documentRect.top; // Container const container = document.createElement('div'); const containerStyle = container.style; this._setImposterStyle(containerStyle, 'all', 'initial'); this._setImposterStyle(containerStyle, 'position', 'absolute'); this._setImposterStyle(containerStyle, 'left', '0'); this._setImposterStyle(containerStyle, 'top', '0'); this._setImposterStyle(containerStyle, 'width', `${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', `${height}px`); } if (imposterRect.x !== elementRect.x || imposterRect.y !== elementRect.y) { left += (elementRect.left - imposterRect.left); top += (elementRect.top - imposterRect.top); this._setImposterStyle(imposterStyle, 'left', `${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'; } }