--- /dev/null
+/**
+ * Copyright (c) 2016 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { ICharSizeService } from 'browser/services/Services';
+import { IBufferService, ICoreService, IOptionsService } from 'common/services/Services';
+
+interface IPosition {
+ start: number;
+ end: number;
+}
+
+/**
+ * Encapsulates the logic for handling compositionstart, compositionupdate and compositionend
+ * events, displaying the in-progress composition to the UI and forwarding the final composition
+ * to the handler.
+ */
+export class CompositionHelper {
+ /**
+ * Whether input composition is currently happening, eg. via a mobile keyboard, speech input or
+ * IME. This variable determines whether the compositionText should be displayed on the UI.
+ */
+ private _isComposing: boolean;
+
+ /**
+ * The position within the input textarea's value of the current composition.
+ */
+ private _compositionPosition: IPosition;
+
+ /**
+ * Whether a composition is in the process of being sent, setting this to false will cancel any
+ * in-progress composition.
+ */
+ private _isSendingComposition: boolean;
+
+ constructor(
+ private readonly _textarea: HTMLTextAreaElement,
+ private readonly _compositionView: HTMLElement,
+ @IBufferService private readonly _bufferService: IBufferService,
+ @IOptionsService private readonly _optionsService: IOptionsService,
+ @ICharSizeService private readonly _charSizeService: ICharSizeService,
+ @ICoreService private readonly _coreService: ICoreService
+ ) {
+ this._isComposing = false;
+ this._isSendingComposition = false;
+ this._compositionPosition = { start: 0, end: 0 };
+ }
+
+ /**
+ * Handles the compositionstart event, activating the composition view.
+ */
+ public compositionstart(): void {
+ this._isComposing = true;
+ this._compositionPosition.start = this._textarea.value.length;
+ this._compositionView.textContent = '';
+ this._compositionView.classList.add('active');
+ }
+
+ /**
+ * Handles the compositionupdate event, updating the composition view.
+ * @param ev The event.
+ */
+ public compositionupdate(ev: CompositionEvent): void {
+ this._compositionView.textContent = ev.data;
+ this.updateCompositionElements();
+ setTimeout(() => {
+ this._compositionPosition.end = this._textarea.value.length;
+ }, 0);
+ }
+
+ /**
+ * Handles the compositionend event, hiding the composition view and sending the composition to
+ * the handler.
+ */
+ public compositionend(): void {
+ this._finalizeComposition(true);
+ }
+
+ /**
+ * Handles the keydown event, routing any necessary events to the CompositionHelper functions.
+ * @param ev The keydown event.
+ * @return Whether the Terminal should continue processing the keydown event.
+ */
+ public keydown(ev: KeyboardEvent): boolean {
+ if (this._isComposing || this._isSendingComposition) {
+ if (ev.keyCode === 229) {
+ // Continue composing if the keyCode is the "composition character"
+ return false;
+ } else if (ev.keyCode === 16 || ev.keyCode === 17 || ev.keyCode === 18) {
+ // Continue composing if the keyCode is a modifier key
+ return false;
+ }
+ // Finish composition immediately. This is mainly here for the case where enter is
+ // pressed and the handler needs to be triggered before the command is executed.
+ this._finalizeComposition(false);
+ }
+
+ if (ev.keyCode === 229) {
+ // If the "composition character" is used but gets to this point it means a non-composition
+ // character (eg. numbers and punctuation) was pressed when the IME was active.
+ this._handleAnyTextareaChanges();
+ return false;
+ }
+
+ return true;
+ }
+
+ /**
+ * Finalizes the composition, resuming regular input actions. This is called when a composition
+ * is ending.
+ * @param waitForPropagation Whether to wait for events to propagate before sending
+ * the input. This should be false if a non-composition keystroke is entered before the
+ * compositionend event is triggered, such as enter, so that the composition is sent before
+ * the command is executed.
+ */
+ private _finalizeComposition(waitForPropagation: boolean): void {
+ this._compositionView.classList.remove('active');
+ this._isComposing = false;
+ this._clearTextareaPosition();
+
+ if (!waitForPropagation) {
+ // Cancel any delayed composition send requests and send the input immediately.
+ this._isSendingComposition = false;
+ const input = this._textarea.value.substring(this._compositionPosition.start, this._compositionPosition.end);
+ this._coreService.triggerDataEvent(input, true);
+ } else {
+ // Make a deep copy of the composition position here as a new compositionstart event may
+ // fire before the setTimeout executes.
+ const currentCompositionPosition = {
+ start: this._compositionPosition.start,
+ end: this._compositionPosition.end
+ };
+
+ // Since composition* events happen before the changes take place in the textarea on most
+ // browsers, use a setTimeout with 0ms time to allow the native compositionend event to
+ // complete. This ensures the correct character is retrieved.
+ // This solution was used because:
+ // - The compositionend event's data property is unreliable, at least on Chromium
+ // - The last compositionupdate event's data property does not always accurately describe
+ // the character, a counter example being Korean where an ending consonsant can move to
+ // the following character if the following input is a vowel.
+ this._isSendingComposition = true;
+ setTimeout(() => {
+ // Ensure that the input has not already been sent
+ if (this._isSendingComposition) {
+ this._isSendingComposition = false;
+ let input;
+ if (this._isComposing) {
+ // Use the end position to get the string if a new composition has started.
+ input = this._textarea.value.substring(currentCompositionPosition.start, currentCompositionPosition.end);
+ } else {
+ // Don't use the end position here in order to pick up any characters after the
+ // composition has finished, for example when typing a non-composition character
+ // (eg. 2) after a composition character.
+ input = this._textarea.value.substring(currentCompositionPosition.start);
+ }
+ this._coreService.triggerDataEvent(input, true);
+ }
+ }, 0);
+ }
+ }
+
+ /**
+ * Apply any changes made to the textarea after the current event chain is allowed to complete.
+ * This should be called when not currently composing but a keydown event with the "composition
+ * character" (229) is triggered, in order to allow non-composition text to be entered when an
+ * IME is active.
+ */
+ private _handleAnyTextareaChanges(): void {
+ const oldValue = this._textarea.value;
+ setTimeout(() => {
+ // Ignore if a composition has started since the timeout
+ if (!this._isComposing) {
+ const newValue = this._textarea.value;
+ const diff = newValue.replace(oldValue, '');
+ if (diff.length > 0) {
+ this._coreService.triggerDataEvent(diff, true);
+ }
+ }
+ }, 0);
+ }
+
+ /**
+ * Positions the composition view on top of the cursor and the textarea just below it (so the
+ * IME helper dialog is positioned correctly).
+ * @param dontRecurse Whether to use setTimeout to recursively trigger another update, this is
+ * necessary as the IME events across browsers are not consistently triggered.
+ */
+ public updateCompositionElements(dontRecurse?: boolean): void {
+ if (!this._isComposing) {
+ return;
+ }
+
+ if (this._bufferService.buffer.isCursorInViewport) {
+ const cellHeight = Math.ceil(this._charSizeService.height * this._optionsService.options.lineHeight);
+ const cursorTop = this._bufferService.buffer.y * cellHeight;
+ const cursorLeft = this._bufferService.buffer.x * this._charSizeService.width;
+
+ this._compositionView.style.left = cursorLeft + 'px';
+ this._compositionView.style.top = cursorTop + 'px';
+ this._compositionView.style.height = cellHeight + 'px';
+ this._compositionView.style.lineHeight = cellHeight + 'px';
+ this._compositionView.style.fontFamily = this._optionsService.options.fontFamily;
+ this._compositionView.style.fontSize = this._optionsService.options.fontSize + 'px';
+ // Sync the textarea to the exact position of the composition view so the IME knows where the
+ // text is.
+ const compositionViewBounds = this._compositionView.getBoundingClientRect();
+ this._textarea.style.left = cursorLeft + 'px';
+ this._textarea.style.top = cursorTop + 'px';
+ this._textarea.style.width = compositionViewBounds.width + 'px';
+ this._textarea.style.height = compositionViewBounds.height + 'px';
+ this._textarea.style.lineHeight = compositionViewBounds.height + 'px';
+ }
+
+ if (!dontRecurse) {
+ setTimeout(() => this.updateCompositionElements(true), 0);
+ }
+ }
+
+ /**
+ * Clears the textarea's position so that the cursor does not blink on IE.
+ * @private
+ */
+ private _clearTextareaPosition(): void {
+ this._textarea.style.left = '';
+ this._textarea.style.top = '';
+ }
+}
projects / VSoRC / .git / blobdiff