Move MouseHelper into browser

src/browser/input/MouseHelper.ts

@@ -0,0 +1,75 @@
+/**
+ * Copyright (c) 2017 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { IMouseHelper } from 'browser/Types';
+import { RenderService } from 'browser/services/RenderService';
+import { ICharSizeService } from 'browser/services/Services';
+
+export class MouseHelper implements IMouseHelper {
+  constructor(
+    private _renderService: RenderService,
+    private _charSizeService: ICharSizeService
+  ) {
+  }
+
+  public static getCoordsRelativeToElement(event: {clientX: number, clientY: number}, element: HTMLElement): [number, number] {
+    const rect = element.getBoundingClientRect();
+    return [event.clientX - rect.left, event.clientY - rect.top];
+  }
+
+  /**
+   * Gets coordinates within the terminal for a particular mouse event. The result
+   * is returned as an array in the form [x, y] instead of an object as it's a
+   * little faster and this function is used in some low level code.
+   * @param event The mouse event.
+   * @param element The terminal's container element.
+   * @param colCount The number of columns in the terminal.
+   * @param rowCount The number of rows n the terminal.
+   * @param isSelection Whether the request is for the selection or not. This will
+   * apply an offset to the x value such that the left half of the cell will
+   * select that cell and the right half will select the next cell.
+   */
+  public getCoords(event: {clientX: number, clientY: number}, element: HTMLElement, colCount: number, rowCount: number, isSelection?: boolean): [number, number] | undefined {
+    // Coordinates cannot be measured if there are no valid
+    if (!this._charSizeService.hasValidSize) {
+      return undefined;
+    }
+
+    const coords = MouseHelper.getCoordsRelativeToElement(event, element);
+    if (!coords) {
+      return undefined;
+    }
+
+    coords[0] = Math.ceil((coords[0] + (isSelection ? this._renderService.dimensions.actualCellWidth / 2 : 0)) / this._renderService.dimensions.actualCellWidth);
+    coords[1] = Math.ceil(coords[1] / this._renderService.dimensions.actualCellHeight);
+
+    // Ensure coordinates are within the terminal viewport. Note that selections
+    // need an addition point of precision to cover the end point (as characters
+    // cover half of one char and half of the next).
+    coords[0] = Math.min(Math.max(coords[0], 1), colCount + (isSelection ? 1 : 0));
+    coords[1] = Math.min(Math.max(coords[1], 1), rowCount);
+
+    return coords;
+  }
+
+  /**
+   * Gets coordinates within the terminal for a particular mouse event, wrapping
+   * them to the bounds of the terminal and adding 32 to both the x and y values
+   * as expected by xterm.
+   * @param event The mouse event.
+   * @param element The terminal's container element.
+   * @param colCount The number of columns in the terminal.
+   * @param rowCount The number of rows in the terminal.
+   */
+  public getRawByteCoords(event: MouseEvent, element: HTMLElement, colCount: number, rowCount: number): { x: number | undefined, y: number | undefined } {
+    const coords = this.getCoords(event, element, colCount, rowCount);
+
+    // xterm sends raw bytes and starts at 32 (SP) for each.
+    const x = coords ? coords[0] + 32 : undefined;
+    const y = coords ? coords[1] + 32 : undefined;
+
+    return { x, y };
+  }
+}