fullpage-scroll-component/dist/lib/StepScroll/hooks/useDebouncedScrollDirection.js

Stepped Scroll Component Library.

'use strict';

Object.defineProperty(exports, '__esModule', { value: true });

var react = require('react');
var debounce = require('lodash/debounce');

function _interopDefaultLegacy (e) { return e && typeof e === 'object' && 'default' in e ? e : { 'default': e }; }

var debounce__default = /*#__PURE__*/_interopDefaultLegacy(debounce);

function useDebouncedScrollDirection({
  upScrollCallback,
  downScrollCallback,
  isPreventDefault,
  debounceDelay = 1000
}) {
  const [scrollDir, setScrollDir] = react.useState("");
  const [touchStart, setTouchStart] = react.useState(0);
  react.useEffect(() => {
    const debouncedScroll = debounce__default["default"](direction => {
      if (direction === "down") {
        if (downScrollCallback && isPreventDefault) {
          downScrollCallback();
        }
      }
      if (direction === "up") {
        if (upScrollCallback && isPreventDefault) {
          upScrollCallback();
        }
      }
    }, debounceDelay);
    const handleScroll = e => {
      if (isPreventDefault) {
        e.preventDefault();
      }
      if (e.deltaY > 0) {
        debouncedScroll("down");
        setScrollDir("down");
      } else if (e.deltaY < 0) {
        debouncedScroll("up");
        setScrollDir("up");
      }
    };
    const onSetTouchStart = e => {
      setTouchStart(e.changedTouches[0].clientY);
    };
    const handleMobileScroll = e => {
      if (isPreventDefault) {
        e.preventDefault();
      }
      if (e.changedTouches[0].clientY < touchStart) {
        debouncedScroll("down");
        setScrollDir("down");
      } else if (e.changedTouches[0].clientY > touchStart) {
        debouncedScroll("up");
        setScrollDir("up");
      }
    };
    window.addEventListener("wheel", handleScroll, {
      passive: false
    });
    window.addEventListener("touchmove", handleMobileScroll, {
      passive: false
    });
    window.addEventListener("touchstart", onSetTouchStart, {
      passive: false
    });
    return () => {
      window.removeEventListener("wheel", handleScroll);
      window.removeEventListener("touchmove", handleMobileScroll);
      window.removeEventListener("touchstart", onSetTouchStart);
    };
  }, [upScrollCallback, downScrollCallback, touchStart]);
  return scrollDir;
}

exports.useDebouncedScrollDirection = useDebouncedScrollDirection;