X-Git-Url: https://git.josue.xyz/?p=VSoRC%2F.git;a=blobdiff_plain;f=node_modules%2Fxterm%2Fsrc%2FAccessibilityManager.ts;fp=node_modules%2Fxterm%2Fsrc%2FAccessibilityManager.ts;h=75393ea4cea8cd04a839c5f0a2db3cf51d64f631;hp=0000000000000000000000000000000000000000;hb=4339da12467b75fb8b6ca831f4bf0081c485ed2c;hpb=af450fde25a9ccf4767b29254c463ffb8ef25237

diff --git a/node_modules/xterm/src/AccessibilityManager.ts b/node_modules/xterm/src/AccessibilityManager.ts
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+++ b/node_modules/xterm/src/AccessibilityManager.ts
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+/**
+ * Copyright (c) 2017 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import * as Strings from './browser/LocalizableStrings';
+import { ITerminal } from './Types';
+import { IBuffer } from 'common/buffer/Types';
+import { isMac } from 'common/Platform';
+import { RenderDebouncer } from 'browser/RenderDebouncer';
+import { addDisposableDomListener } from 'browser/Lifecycle';
+import { Disposable } from 'common/Lifecycle';
+import { ScreenDprMonitor } from 'browser/ScreenDprMonitor';
+import { IRenderService } from 'browser/services/Services';
+
+const MAX_ROWS_TO_READ = 20;
+
+const enum BoundaryPosition {
+  TOP,
+  BOTTOM
+}
+
+export class AccessibilityManager extends Disposable {
+  private _accessibilityTreeRoot: HTMLElement;
+  private _rowContainer: HTMLElement;
+  private _rowElements: HTMLElement[];
+  private _liveRegion: HTMLElement;
+  private _liveRegionLineCount: number = 0;
+
+  private _renderRowsDebouncer: RenderDebouncer;
+  private _screenDprMonitor: ScreenDprMonitor;
+
+  private _topBoundaryFocusListener: (e: FocusEvent) => void;
+  private _bottomBoundaryFocusListener: (e: FocusEvent) => void;
+
+  /**
+   * This queue has a character pushed to it for keys that are pressed, if the
+   * next character added to the terminal is equal to the key char then it is
+   * not announced (added to live region) because it has already been announced
+   * by the textarea event (which cannot be canceled). There are some race
+   * condition cases if there is typing while data is streaming, but this covers
+   * the main case of typing into the prompt and inputting the answer to a
+   * question (Y/N, etc.).
+   */
+  private _charsToConsume: string[] = [];
+
+  private _charsToAnnounce: string = '';
+
+  constructor(
+    private readonly _terminal: ITerminal,
+    private readonly _renderService: IRenderService
+  ) {
+    super();
+    this._accessibilityTreeRoot = document.createElement('div');
+    this._accessibilityTreeRoot.classList.add('xterm-accessibility');
+
+    this._rowContainer = document.createElement('div');
+    this._rowContainer.classList.add('xterm-accessibility-tree');
+    this._rowElements = [];
+    for (let i = 0; i < this._terminal.rows; i++) {
+      this._rowElements[i] = this._createAccessibilityTreeNode();
+      this._rowContainer.appendChild(this._rowElements[i]);
+    }
+
+    this._topBoundaryFocusListener = e => this._onBoundaryFocus(e, BoundaryPosition.TOP);
+    this._bottomBoundaryFocusListener = e => this._onBoundaryFocus(e, BoundaryPosition.BOTTOM);
+    this._rowElements[0].addEventListener('focus', this._topBoundaryFocusListener);
+    this._rowElements[this._rowElements.length - 1].addEventListener('focus', this._bottomBoundaryFocusListener);
+
+    this._refreshRowsDimensions();
+    this._accessibilityTreeRoot.appendChild(this._rowContainer);
+
+    this._renderRowsDebouncer = new RenderDebouncer(this._renderRows.bind(this));
+    this._refreshRows();
+
+    this._liveRegion = document.createElement('div');
+    this._liveRegion.classList.add('live-region');
+    this._liveRegion.setAttribute('aria-live', 'assertive');
+    this._accessibilityTreeRoot.appendChild(this._liveRegion);
+
+    this._terminal.element.insertAdjacentElement('afterbegin', this._accessibilityTreeRoot);
+
+    this.register(this._renderRowsDebouncer);
+    this.register(this._terminal.onResize(e => this._onResize(e.rows)));
+    this.register(this._terminal.onRender(e => this._refreshRows(e.start, e.end)));
+    this.register(this._terminal.onScroll(() => this._refreshRows()));
+    // Line feed is an issue as the prompt won't be read out after a command is run
+    this.register(this._terminal.onA11yChar(char => this._onChar(char)));
+    this.register(this._terminal.onLineFeed(() => this._onChar('\n')));
+    this.register(this._terminal.onA11yTab(spaceCount => this._onTab(spaceCount)));
+    this.register(this._terminal.onKey(e => this._onKey(e.key)));
+    this.register(this._terminal.onBlur(() => this._clearLiveRegion()));
+    this.register(this._renderService.onDimensionsChange(() => this._refreshRowsDimensions()));
+
+    this._screenDprMonitor = new ScreenDprMonitor();
+    this.register(this._screenDprMonitor);
+    this._screenDprMonitor.setListener(() => this._refreshRowsDimensions());
+    // This shouldn't be needed on modern browsers but is present in case the
+    // media query that drives the ScreenDprMonitor isn't supported
+    this.register(addDisposableDomListener(window, 'resize', () => this._refreshRowsDimensions()));
+  }
+
+  public dispose(): void {
+    super.dispose();
+    this._terminal.element.removeChild(this._accessibilityTreeRoot);
+    this._rowElements.length = 0;
+  }
+
+  private _onBoundaryFocus(e: FocusEvent, position: BoundaryPosition): void {
+    const boundaryElement = <HTMLElement>e.target;
+    const beforeBoundaryElement = this._rowElements[position === BoundaryPosition.TOP ? 1 : this._rowElements.length - 2];
+
+    // Don't scroll if the buffer top has reached the end in that direction
+    const posInSet = boundaryElement.getAttribute('aria-posinset');
+    const lastRowPos = position === BoundaryPosition.TOP ? '1' : `${this._terminal.buffer.lines.length}`;
+    if (posInSet === lastRowPos) {
+      return;
+    }
+
+    // Don't scroll when the last focused item was not the second row (focus is going the other
+    // direction)
+    if (e.relatedTarget !== beforeBoundaryElement) {
+      return;
+    }
+
+    // Remove old boundary element from array
+    let topBoundaryElement: HTMLElement;
+    let bottomBoundaryElement: HTMLElement;
+    if (position === BoundaryPosition.TOP) {
+      topBoundaryElement = boundaryElement;
+      bottomBoundaryElement = this._rowElements.pop()!;
+      this._rowContainer.removeChild(bottomBoundaryElement);
+    } else {
+      topBoundaryElement = this._rowElements.shift()!;
+      bottomBoundaryElement = boundaryElement;
+      this._rowContainer.removeChild(topBoundaryElement);
+    }
+
+    // Remove listeners from old boundary elements
+    topBoundaryElement.removeEventListener('focus', this._topBoundaryFocusListener);
+    bottomBoundaryElement.removeEventListener('focus', this._bottomBoundaryFocusListener);
+
+    // Add new element to array/DOM
+    if (position === BoundaryPosition.TOP) {
+      const newElement = this._createAccessibilityTreeNode();
+      this._rowElements.unshift(newElement);
+      this._rowContainer.insertAdjacentElement('afterbegin', newElement);
+    } else {
+      const newElement = this._createAccessibilityTreeNode();
+      this._rowElements.push(newElement);
+      this._rowContainer.appendChild(newElement);
+    }
+
+    // Add listeners to new boundary elements
+    this._rowElements[0].addEventListener('focus', this._topBoundaryFocusListener);
+    this._rowElements[this._rowElements.length - 1].addEventListener('focus', this._bottomBoundaryFocusListener);
+
+    // Scroll up
+    this._terminal.scrollLines(position === BoundaryPosition.TOP ? -1 : 1);
+
+    // Focus new boundary before element
+    this._rowElements[position === BoundaryPosition.TOP ? 1 : this._rowElements.length - 2].focus();
+
+    // Prevent the standard behavior
+    e.preventDefault();
+    e.stopImmediatePropagation();
+  }
+
+  private _onResize(rows: number): void {
+    // Remove bottom boundary listener
+    this._rowElements[this._rowElements.length - 1].removeEventListener('focus', this._bottomBoundaryFocusListener);
+
+    // Grow rows as required
+    for (let i = this._rowContainer.children.length; i < this._terminal.rows; i++) {
+      this._rowElements[i] = this._createAccessibilityTreeNode();
+      this._rowContainer.appendChild(this._rowElements[i]);
+    }
+    // Shrink rows as required
+    while (this._rowElements.length > rows) {
+      this._rowContainer.removeChild(this._rowElements.pop()!);
+    }
+
+    // Add bottom boundary listener
+    this._rowElements[this._rowElements.length - 1].addEventListener('focus', this._bottomBoundaryFocusListener);
+
+    this._refreshRowsDimensions();
+  }
+
+  private _createAccessibilityTreeNode(): HTMLElement {
+    const element = document.createElement('div');
+    element.setAttribute('role', 'listitem');
+    element.tabIndex = -1;
+    this._refreshRowDimensions(element);
+    return element;
+  }
+
+  private _onTab(spaceCount: number): void {
+    for (let i = 0; i < spaceCount; i++) {
+      this._onChar(' ');
+    }
+  }
+
+  private _onChar(char: string): void {
+    if (this._liveRegionLineCount < MAX_ROWS_TO_READ + 1) {
+      if (this._charsToConsume.length > 0) {
+        // Have the screen reader ignore the char if it was just input
+        const shiftedChar = this._charsToConsume.shift();
+        if (shiftedChar !== char) {
+          this._charsToAnnounce += char;
+        }
+      } else {
+        this._charsToAnnounce += char;
+      }
+
+      if (char === '\n') {
+        this._liveRegionLineCount++;
+        if (this._liveRegionLineCount === MAX_ROWS_TO_READ + 1) {
+          this._liveRegion.textContent += Strings.tooMuchOutput;
+        }
+      }
+
+      // Only detach/attach on mac as otherwise messages can go unaccounced
+      if (isMac) {
+        if (this._liveRegion.textContent && this._liveRegion.textContent.length > 0 && !this._liveRegion.parentNode) {
+          setTimeout(() => {
+            this._accessibilityTreeRoot.appendChild(this._liveRegion);
+          }, 0);
+        }
+      }
+    }
+  }
+
+  private _clearLiveRegion(): void {
+    this._liveRegion.textContent = '';
+    this._liveRegionLineCount = 0;
+
+    // Only detach/attach on mac as otherwise messages can go unaccounced
+    if (isMac) {
+      if (this._liveRegion.parentNode) {
+        this._accessibilityTreeRoot.removeChild(this._liveRegion);
+      }
+    }
+  }
+
+  private _onKey(keyChar: string): void {
+    this._clearLiveRegion();
+    this._charsToConsume.push(keyChar);
+  }
+
+  private _refreshRows(start?: number, end?: number): void {
+    this._renderRowsDebouncer.refresh(start, end, this._terminal.rows);
+  }
+
+  private _renderRows(start: number, end: number): void {
+    const buffer: IBuffer = this._terminal.buffer;
+    const setSize = buffer.lines.length.toString();
+    for (let i = start; i <= end; i++) {
+      const lineData = buffer.translateBufferLineToString(buffer.ydisp + i, true);
+      const posInSet = (buffer.ydisp + i + 1).toString();
+      const element = this._rowElements[i];
+      if (element) {
+        if (lineData.length === 0) {
+          element.innerHTML = '&nbsp;';
+        } else {
+          element.textContent = lineData;
+        }
+        element.setAttribute('aria-posinset', posInSet);
+        element.setAttribute('aria-setsize', setSize);
+      }
+    }
+    this._announceCharacters();
+  }
+
+  private _refreshRowsDimensions(): void {
+    if (!this._renderService.dimensions.actualCellHeight) {
+      return;
+    }
+    if (this._rowElements.length !== this._terminal.rows) {
+      this._onResize(this._terminal.rows);
+    }
+    for (let i = 0; i < this._terminal.rows; i++) {
+      this._refreshRowDimensions(this._rowElements[i]);
+    }
+  }
+
+  private _refreshRowDimensions(element: HTMLElement): void {
+    element.style.height = `${this._renderService.dimensions.actualCellHeight}px`;
+  }
+
+  private _announceCharacters(): void {
+    if (this._charsToAnnounce.length === 0) {
+      return;
+    }
+    this._liveRegion.textContent += this._charsToAnnounce;
+    this._charsToAnnounce = '';
+  }
+}