Basic fetching of coordinates

src/SelectionManager.ts

@@ -0,0 +1,65 @@
+/**
+ * @license MIT
+ */
+
+import { CharMeasure } from './utils/CharMeasure';
+import { CircularList } from './utils/CircularList';
+import * as Mouse from './utils/Mouse';
+
+export class SelectionManager {
+  private _selectionStart: [number, number];
+  private _selectionEnd: [number, number];
+
+  private _buffer: CircularList<any>;
+  private _rowContainer: HTMLElement;
+  private _charMeasure: CharMeasure;
+
+  private _mouseMoveListener: EventListener;
+
+  constructor(buffer: CircularList<any>, rowContainer: HTMLElement, charMeasure: CharMeasure) {
+    this._rowContainer = rowContainer;
+    this._buffer = buffer;
+    this._charMeasure = charMeasure;
+    this._attachListeners();
+  }
+
+  private _attachListeners() {
+    this._mouseMoveListener = event => this._onMouseMove(<MouseEvent>event);
+
+    this._buffer.on('trim', amount => this._onTrim(amount));
+    this._rowContainer.addEventListener('mousedown', event => this._onMouseDown(event));
+    this._rowContainer.addEventListener('mouseup', event => this._onMouseUp(event));
+  }
+
+  public get selectionText(): string {
+    if (!this._selectionStart || !this._selectionEnd) {
+      return null;
+    }
+    return '';
+  }
+
+  private _onTrim(amount: number) {
+    console.log('trimmed: ' + amount);
+  }
+
+  private _onMouseDown(event: MouseEvent) {
+    this._selectionStart = Mouse.getCoords(event, this._rowContainer, this._charMeasure);
+    if (this._selectionStart) {
+      this._rowContainer.addEventListener('mousemove', this._mouseMoveListener);
+    }
+  }
+
+  private _onMouseMove(event: MouseEvent) {
+    this._selectionEnd = Mouse.getCoords(event, this._rowContainer, this._charMeasure);
+  }
+
+  private _onMouseUp(event: MouseEvent) {
+    console.log('mouseup');
+    console.log('start', this._selectionStart);
+    console.log('end', this._selectionEnd);
+    if (!this._selectionStart) {
+      return;
+    }
+    this._rowContainer.removeEventListener('mousemove', this._mouseMoveListener);
+  }
+}