/**
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 */

import {selectionAlwaysOnDisplay} from '@lexical/utils';
import {defineExtension, safeCast} from 'lexical';

import {namedSignals} from './namedSignals';
import {effect} from './signals';

export interface SelectionAlwaysOnDisplayConfig {
  disabled: boolean;
  onReposition: undefined | ((node: readonly HTMLElement[]) => void);
}

/**
 * An extension that highlights selected content in the Lexical editor
 * even when the editor is not currently focused.
 */
export const SelectionAlwaysOnDisplayExtension = defineExtension({
  build: (editor, config, state) => namedSignals(config),
  config: safeCast<SelectionAlwaysOnDisplayConfig>({
    disabled: false,
    onReposition: undefined,
  }),
  name: '@lexical/utils/SelectionAlwaysOnDisplay',
  register: (editor, config, state) => {
    const stores = state.getOutput();
    return effect(() => {
      if (!stores.disabled.value) {
        return selectionAlwaysOnDisplay(editor, stores.onReposition.value);
      }
    });
  },
});