Share selection render model code

src/browser/renderer/shared/SelectionRenderModel.ts

@@ -0,0 +1,85 @@
+/**
+ * Copyright (c) 2022 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { ISelectionRenderModel } from 'browser/renderer/shared/Types';
+import { Terminal } from 'xterm';
+
+class SelectionRenderModel implements ISelectionRenderModel {
+  public hasSelection!: boolean;
+  public columnSelectMode!: boolean;
+  public viewportStartRow!: number;
+  public viewportEndRow!: number;
+  public viewportCappedStartRow!: number;
+  public viewportCappedEndRow!: number;
+  public startCol!: number;
+  public endCol!: number;
+
+  constructor() {
+    this.clear();
+  }
+
+  public clear(): void {
+    this.hasSelection = false;
+    this.columnSelectMode = false;
+    this.viewportStartRow = 0;
+    this.viewportEndRow = 0;
+    this.viewportCappedStartRow = 0;
+    this.viewportCappedEndRow = 0;
+    this.startCol = 0;
+    this.endCol = 0;
+  }
+
+  public update(terminal: Terminal, start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {
+    // Selection does not exist
+    if (!start || !end || (start[0] === end[0] && start[1] === end[1])) {
+      this.clear();
+      return;
+    }
+
+    // Translate from buffer position to viewport position
+    const viewportStartRow = start[1] - terminal.buffer.active.viewportY;
+    const viewportEndRow = end[1] - terminal.buffer.active.viewportY;
+    const viewportCappedStartRow = Math.max(viewportStartRow, 0);
+    const viewportCappedEndRow = Math.min(viewportEndRow, terminal.rows - 1);
+
+    // No need to draw the selection
+    if (viewportCappedStartRow >= terminal.rows || viewportCappedEndRow < 0) {
+      this.clear();
+      return;
+    }
+
+    this.hasSelection = true;
+    this.columnSelectMode = columnSelectMode;
+    this.viewportStartRow = viewportStartRow;
+    this.viewportEndRow = viewportEndRow;
+    this.viewportCappedStartRow = viewportCappedStartRow;
+    this.viewportCappedEndRow = viewportCappedEndRow;
+    this.startCol = start[0];
+    this.endCol = end[0];
+  }
+
+  public isCellSelected(terminal: Terminal, x: number, y: number): boolean {
+    if (!this.hasSelection) {
+      return false;
+    }
+    y -= terminal.buffer.active.viewportY;
+    if (this.columnSelectMode) {
+      if (this.startCol <= this.endCol) {
+        return x >= this.startCol && y >= this.viewportCappedStartRow &&
+          x < this.endCol && y <= this.viewportCappedEndRow;
+      }
+      return x < this.startCol && y >= this.viewportCappedStartRow &&
+        x >= this.endCol && y <= this.viewportCappedEndRow;
+    }
+    return (y > this.viewportStartRow && y < this.viewportEndRow) ||
+      (this.viewportStartRow === this.viewportEndRow && y === this.viewportStartRow && x >= this.startCol && x < this.endCol) ||
+      (this.viewportStartRow < this.viewportEndRow && y === this.viewportEndRow && x < this.endCol) ||
+      (this.viewportStartRow < this.viewportEndRow && y === this.viewportStartRow && x >= this.startCol);
+  }
+}
+
+export function createSelectionRenderModel(): ISelectionRenderModel {
+  return new SelectionRenderModel();
+}