masonic/src/use-container-position.ts

<hr> <div align="center"> <h1 align="center"> 🧱 masonic </h1>

import useLayoutEffect from "@react-hook/passive-layout-effect";
import * as React from "react";

/**
 * A hook for measuring the width of the grid container, as well as its distance
 * from the top of the document. These values are necessary to correctly calculate the number/width
 * of columns to render, as well as the number of rows to render.
 *
 * @param elementRef - A `ref` object created by `React.useRef()`. That ref should be provided to the
 *   `containerRef` property in `useMasonry()`.
 * @param deps - You can force this hook to recalculate the `offset` and `width` whenever this
 *   dependencies list changes. A common dependencies list might look like `[windowWidth, windowHeight]`,
 *   which would force the hook to recalculate any time the size of the browser `window` changed.
 */
export function useContainerPosition(
  elementRef: React.MutableRefObject<HTMLElement | null>,
  deps: React.DependencyList = emptyArr
): ContainerPosition {
  const [containerPosition, setContainerPosition] =
    React.useState<ContainerPosition>({ offset: 0, width: 0 });

  useLayoutEffect(() => {
    const { current } = elementRef;
    if (current !== null) {
      let offset = 0;
      let el = current;

      do {
        offset += el.offsetTop || 0;
        el = el.offsetParent as HTMLElement;
      } while (el);

      if (
        offset !== containerPosition.offset ||
        current.offsetWidth !== containerPosition.width
      ) {
        setContainerPosition({
          offset,
          width: current.offsetWidth,
        });
      }
    }
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, deps);

  return containerPosition;
}

export interface ContainerPosition {
  /**
   * The distance in pixels between the top of the element in `elementRef` and the top of
   * the `document.documentElement`.
   */
  offset: number;
  /**
   * The `offsetWidth` of the element in `elementRef`.
   */
  width: number;
}

const emptyArr: [] = [];