text: // Copyright (c) 2015 Uber Technologies, Inc.
  
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  // THE SOFTWARE.
  import * as React from 'react';
  import {useEffect, useState, useMemo} from 'react';
  import * as PropTypes from 'prop-types';
  import mapboxgl from '../utils/mapboxgl';
  import useMapControl, {mapControlDefaultProps, mapControlPropTypes} from './use-map-control';
  
  const propTypes = Object.assign({}, mapControlPropTypes, {
    className: PropTypes.string,
    style: PropTypes.object,
    maxWidth: PropTypes.number,
    unit: PropTypes.oneOf(['imperial', 'metric', 'nautical'])
  });
  
  const defaultProps = Object.assign({}, mapControlDefaultProps, {
    className: '',
    maxWidth: 100,
    unit: 'metric'
  });
  
  function ScaleControl(props) {
    const {context, containerRef} = useMapControl(props);
    const [mapboxScaleControl, createMapboxScaleControl] = useState(null);
  
    useEffect(() => {
      if (context.map) {
        const control = new mapboxgl.ScaleControl();
        control._map = context.map;
        control._container = containerRef.current;
        createMapboxScaleControl(control);
      }
    }, [context.map]);
  
    if (mapboxScaleControl) {
      mapboxScaleControl.options = props;
      mapboxScaleControl._onMove();
    }
  
    const style = useMemo(() => ({position: 'absolute', ...props.style}), [props.style]);
  
    return (
      <div style={style} className={props.className}>
        <div ref={containerRef} className="mapboxgl-ctrl mapboxgl-ctrl-scale" />
      </div>
    );
  }
  
  ScaleControl.propTypes = propTypes;
  ScaleControl.defaultProps = defaultProps;
  
  export default React.memo(ScaleControl);
  