tweb-i2p/src/helpers/selectionSaver.ts

/*
 * https://github.com/morethanwords/tweb
 * Copyright (C) 2019-2021 Eduard Kuzmenko
 * https://github.com/morethanwords/tweb/blob/master/LICENSE
 */

import cancelSelection from "./dom/cancelSelection";

export default class SelectionSaver {
  private input: HTMLElement;
  private range: Range;

  public save() {
    const input = document.activeElement as HTMLElement;
    if(input.isContentEditable || input.tagName === 'INPUT') {
      this.input = input;
    }

    const selection = document.getSelection();
    if(!selection.rangeCount || selection.isCollapsed) {
      return;
    }

    this.range = selection.getRangeAt(0);
  }

  public restore() {
    if(!this.range) {
      cancelSelection();
      return;
    }

    const selection = window.getSelection();
    selection.removeAllRanges();
    selection.addRange(this.range);
    if(this.input) {
      this.input.focus();
    }
  }
}