/**
 * Copyright (c) Nicolas Gallagher
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @flow
 */

export function isSelectionValid(): boolean {
  const selection = window.getSelection()
  if (!selection) return false
  const string = selection.toString()
  const anchorNode = selection.anchorNode
  const focusNode = selection.focusNode
  const isTextNode =
    (anchorNode && anchorNode.nodeType === window.Node.TEXT_NODE) ||
    (focusNode && focusNode.nodeType === window.Node.TEXT_NODE)
  return string.length >= 1 && string !== '\n' && !!isTextNode
}