/**
 * Finds displaySet by UID across all displaySets inside studyMetadata
 * @param {Array} studyMetadata
 * @param {string} displaySetInstanceUID
 */
export default function findDisplaySetByUID(
  studyMetadata,
  displaySetInstanceUID
) {
  if (!Array.isArray(studyMetadata)) return null;

  const allDisplaySets = studyMetadata.reduce((all, current) => {
    let currentDisplaySet = [];
    if (current && Array.isArray(current.displaySets)) {
      currentDisplaySet = current.displaySets;
    }
    return all.concat(currentDisplaySet);
  }, []);

  const bySetInstanceUID = ds =>
    ds.displaySetInstanceUID === displaySetInstanceUID;

  const displaySet = allDisplaySets.find(bySetInstanceUID);
  return displaySet || null;
}