@pdf-viewer/react/dist/utils/hooks/useGrabScroll.js

A react-pdf-viewer component for React and Next.js. Suitable for react-pdf document.

import { useState as T, useRef as p, useCallback as c, useEffect as X } from "react";
const b = ({
  isPressed: v,
  scrollSpeed: i = 2
}) => {
  const [L, f] = T("unset"), t = p(null), u = p({
    startY: 0,
    startX: 0,
    startScrollTop: 0,
    startScrollLeft: 0
  }), o = c((r) => {
    t.current && (u.current = {
      startY: r.pageY,
      startX: r.pageX,
      startScrollTop: t.current.scrollTop,
      startScrollLeft: t.current.scrollLeft
    });
  }, []), e = c(() => {
    f("smooth");
  }, []), s = c(
    (r) => {
      if (!v || !t.current)
        return;
      r.preventDefault(), f("unset");
      const { startX: n, startY: a, startScrollTop: l, startScrollLeft: d } = u.current, h = (r.pageX - n) * i, w = (r.pageY - a) * i;
      t.current.scrollTop = l - w, t.current.scrollLeft = d - h;
    },
    [v, i, t]
  ), S = c(
    (r) => {
      var n, a, l;
      t.current && ((n = t.current) == null || n.removeEventListener("mousedown", o), (a = t.current) == null || a.removeEventListener("mouseup", e), (l = t.current) == null || l.removeEventListener("mousemove", s)), t.current = r, r && (r == null || r.addEventListener("mousedown", o, { capture: !0 }), r == null || r.addEventListener("mouseup", e), r == null || r.addEventListener("mousemove", s));
    },
    [o, e, s]
  ), E = c(() => {
    u.current = {
      ...u.current,
      startScrollTop: 0,
      startScrollLeft: 0
    };
  }, []);
  return X(() => () => {
    t.current && (t.current.removeEventListener("mousedown", o), t.current.removeEventListener("mouseup", e), t.current.removeEventListener("mousemove", s));
  }, [o, e, s]), {
    initializeGrabScroll: S,
    scrollBehavior: L,
    resetGrabState: E
  };
};
export {
  b as useGrabScroll
};