import { useContext, useCallback, useState } from 'react';
import { HackleContext } from '../components';
import { InputUtil } from '../utils';

export function useFeature(featureKey: number): boolean {
  const { hackle, userVersion } = useContext(HackleContext);
  const getIsOn = useCallback(() => {
    return hackle?.isFeatureOnSync(featureKey) || false;
  }, [featureKey, hackle]);

  const [isOn, setIsOn] = useState(() => {
    if (!hackle) {
      return false;
    }
    return getIsOn();
  });

  const currentInput = {
    key: featureKey,
    userVersion,
  };

  const [prevInput, setPrevInput] = useState(currentInput);

  if (!InputUtil.isInputEqual(prevInput, currentInput)) {
    setPrevInput(currentInput);
    setIsOn(getIsOn());
  }

  return isOn;
}