@atlaskit/pragmatic-drag-and-drop-react-beautiful-dnd-migration/dist/es2019/utils/get-best-cross-axis-droppable.js

An optional Pragmatic drag and drop package that enables rapid migration from react-beautiful-dnd to Pragmatic drag and drop

// eslint-disable-next-line import/no-extraneous-dependencies

import { attributes, customAttributes, getAttribute } from './attributes';
import { findElementAll } from './find-element';
function getDroppablesOfType({
  contextId,
  type
}) {
  return findElementAll({
    attribute: attributes.droppable.contextId,
    value: contextId
  }, {
    attribute: customAttributes.droppable.type,
    value: type
  });
}

/**
 * This is similar to the function of the same name in `react-beautiful-dnd`.
 *
 * Many of the checks from rbd are removed though, such as visibility checks.
 */
export function getBestCrossAxisDroppable({
  droppableId,
  type,
  isMovingForward,
  contextId,
  droppableRegistry
}) {
  const droppables = getDroppablesOfType({
    contextId,
    type
  });
  const currentIndex = droppables.findIndex(element => getAttribute(element, attributes.droppable.id) === droppableId);
  const candidates = droppables.filter((_, index) => {
    /**
     * We are following the DOM order of the droppables,
     * so keep only those that are before/after the current.
     */
    if (isMovingForward) {
      return index > currentIndex;
    }
    return index < currentIndex;
  }).filter(element => {
    /**
     * Filter out the disabled droppables.
     */
    const droppableId = getAttribute(element, attributes.droppable.id);
    const entry = droppableRegistry.getEntry({
      droppableId
    });
    const isValidCandidate = entry && !entry.isDropDisabled;
    return isValidCandidate;
  });

  /**
   * If we're moving forward then take the first candidate,
   * if moving backwards take the last candidate
   * (because it is closest to where the current is).
   *
   * Using `.at()` provides a safer type, making us handle the `undefined` case.
   */
  const bestCandidate = isMovingForward ? candidates.at(0) : candidates.at(-1);
  return bestCandidate !== null && bestCandidate !== void 0 ? bestCandidate : null;
}