/*
 * Copyright 2020 Adobe. All rights reserved.
 * This file is licensed to you under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License. You may obtain a copy
 * of the License at http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under
 * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
 * OF ANY KIND, either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */

import {Key} from '@react-types/shared';

/**
 * A Selection is a special Set containing Keys, which also has an anchor
 * and current selected key for use when range selecting.
 */
export class Selection extends Set<Key> {
  anchorKey: Key | null;
  currentKey: Key | null;

  constructor(keys?: Iterable<Key> | Selection, anchorKey?: Key | null, currentKey?: Key | null) {
    super(keys);
    if (keys instanceof Selection) {
      this.anchorKey = anchorKey ?? keys.anchorKey;
      this.currentKey = currentKey ?? keys.currentKey;
    } else {
      this.anchorKey = anchorKey ?? null;
      this.currentKey = currentKey ?? null;
    }
  }
}