airbnb/caravel

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * 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 CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import { isNil } from 'lodash';

export default function extent<T = number | string | Date | undefined | null>(
  values: T[],
) {
  let min: T | undefined;
  let max: T | undefined;
  // eslint-disable-next-line no-restricted-syntax
  for (const value of values) {
    if (value !== null) {
      if (isNil(min)) {
        if (value !== undefined) {
          min = value;
          max = value;
        }
      } else if (value !== undefined) {
        if (min > value) {
          min = value;
        }
        if (!isNil(max)) {
          if (max < value) {
            max = value;
          }
        }
      }
    }
  }
  return [min, max];
}