Move handler into CoreService and adopt

This also fine tunes some of the data events to not clear selection
and scroll to the bottom of the viewport anymore.

Part of #1507
Fixes #2112

src/common/services/CoreService.ts

@@ -0,0 +1,43 @@
+/**
+ * Copyright (c) 2019 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { ICoreService, IOptionsService, IBufferService } from 'common/services/Services';
+import { EventEmitter, IEvent } from 'common/EventEmitter';
+
+export class CoreService implements ICoreService {
+  private _onData = new EventEmitter<string>();
+  public get onData(): IEvent<string> { return this._onData.event; }
+  private _onUserInput = new EventEmitter<void>();
+  public get onUserInput(): IEvent<void> { return this._onUserInput.event; }
+
+  constructor(
+    // TODO: Move this into a service
+    private readonly _scrollToBottom: () => void,
+    private readonly _bufferService: IBufferService,
+    private readonly _optionsService: IOptionsService
+  ) {
+  }
+
+  public triggerDataEvent(data: string, wasUserInput: boolean = false): void {
+    // Prevents all events to pty process if stdin is disabled
+    if (this._optionsService.options.disableStdin) {
+      return;
+    }
+
+    // Input is being sent to the terminal, the terminal should focus the prompt.
+    const buffer = this._bufferService.buffer;
+    if (buffer.ybase !== buffer.ydisp) {
+      this._scrollToBottom();
+    }
+
+    // Fire onUserInput so listeners can react as well (eg. clear selection)
+    if (wasUserInput) {
+      this._onUserInput.fire();
+    }
+
+    // Fire onData API
+    this._onData.fire(data);
+  }
+}

src/common/services/Services.d.ts

@@ -18,6 +18,21 @@ export interface IBufferService {
   reset(): void;
 }
 
+export interface ICoreService {
+  readonly onData: IEvent<string>;
+  readonly onUserInput: IEvent<void>;
+
+  /**
+   * Triggers the onData event in the public API.
+   * @param data The data that is being emitted.
+   * @param wasFromUser Whether the data originated from the user (as opposed to
+   * resulting from parsing incoming data). When true this will also:
+   * - Scroll to the bottom of the buffer.s
+   * - Fire the `onUserInput` event (so selection can be cleared).
+    */
+    triggerDataEvent(data: string, wasUserInput?: boolean): void;
+}
+
 export interface IOptionsService {
   readonly options: ITerminalOptions;