import * as React from 'react';
import canUseDom from 'rc-util/lib/Dom/canUseDom';

const canUseDocElement = () => canUseDom() && window.document.documentElement;

let flexGapSupported: boolean | undefined;
export const detectFlexGapSupported = () => {
  if (!canUseDocElement()) {
    return false;
  }

  if (flexGapSupported !== undefined) {
    return flexGapSupported;
  }

  // create flex container with row-gap set
  const flex = document.createElement('div');
  flex.style.display = 'flex';
  flex.style.flexDirection = 'column';
  flex.style.rowGap = '1px';

  // create two, elements inside it
  flex.appendChild(document.createElement('div'));
  flex.appendChild(document.createElement('div'));

  // append to the DOM (needed to obtain scrollHeight)
  document.body.appendChild(flex);
  flexGapSupported = flex.scrollHeight === 1; // flex container should be 1px high from the row-gap
  document.body.removeChild(flex);

  return flexGapSupported;
};

export default () => {
  const [flexible, setFlexible] = React.useState(false);
  React.useEffect(() => {
    setFlexible(detectFlexGapSupported());
  }, []);

  return flexible;
};