@navikt/ds-react/src/util/hooks/descendants/utils.ts

React components from the Norwegian Labour and Welfare Administration.

/**
 * Sort an array of DOM nodes according to the HTML tree order
 * @see http://www.w3.org/TR/html5/infrastructure.html#tree-order
 * Inspired by
 * - https://github.com/floating-ui/floating-ui/blob/8e449abb0bfda143c6a6eb01d3e6943c095b744f/packages/react/src/components/FloatingList.tsx#L8
 * - https://github.com/chakra-ui/chakra-ui/tree/5ec0be610b5a69afba01a9c22365155c1b519136/packages/components/descendant
 */
export function sortNodes(nodes: Node[]) {
  return nodes.sort((a, b) => {
    const compare = a.compareDocumentPosition(b);

    if (
      compare & Node.DOCUMENT_POSITION_FOLLOWING ||
      compare & Node.DOCUMENT_POSITION_CONTAINED_BY
    ) {
      // a < b
      return -1;
    }

    if (
      compare & Node.DOCUMENT_POSITION_PRECEDING ||
      compare & Node.DOCUMENT_POSITION_CONTAINS
    ) {
      // a > b
      return 1;
    }

    if (
      compare & Node.DOCUMENT_POSITION_DISCONNECTED ||
      compare & Node.DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC
    ) {
      throw Error("Cannot sort the given nodes.");
    }

    return 0;
  });
}

export const isElement = (el: any): el is HTMLElement =>
  typeof el === "object" &&
  "nodeType" in el &&
  el.nodeType === Node.ELEMENT_NODE;

export function getNextIndex(current: number, max: number, loop: boolean) {
  let next = current + 1;
  if (loop && next >= max) next = 0;
  return next;
}

export function getPrevIndex(current: number, max: number, loop: boolean) {
  let next = current - 1;
  if (loop && next < 0) next = max;
  return next;
}

export const cast = <T>(value: any) => value as T;