Function createRecursiveDrawerItemsData

lib/utils/drawer-utils.react.js:32–72

(
  childThreadInfosMap: {
    +[id: string]: $ReadOnlyArray<ResolvedThreadInfo>,
  },
  communities: $ReadOnlyArray<ResolvedThreadInfo>,
  labelStyles: $ReadOnlyArray<LabelStyleType>,
  maxDepth: number,
)

}

function createRecursiveDrawerItemsData<LabelStyleType>(
  childThreadInfosMap: {
    +[id: string]: $ReadOnlyArray<ResolvedThreadInfo>,
  },
  communities: $ReadOnlyArray<ResolvedThreadInfo>,
  labelStyles: $ReadOnlyArray<LabelStyleType>,
  maxDepth: number,
): $ReadOnlyArray<CommunityDrawerItemData<LabelStyleType>> {
  const result: Array<WritableCommunityDrawerItemData<LabelStyleType>> =
    communities.map(community => ({
      threadInfo: community,
      itemChildren: [],
      labelStyle: labelStyles[0],
      hasSubchannelsButton: false,
    }));
  result.sort(compareCommunityDrawerItemData);
  let queue = result.map(item => [item, 0]);

  for (let i = 0; i < queue.length; i++) {
    const [item, lvl] = queue[i];
    const itemChildThreadInfos = childThreadInfosMap[item.threadInfo.id] ?? [];

    if (lvl < maxDepth) {
      item.itemChildren = itemChildThreadInfos
        .filter(childItem => communitySubthreads.includes(childItem.type))
        .map(childItem => ({
          threadInfo: childItem,
          itemChildren: [],
          labelStyle: labelStyles[Math.min(lvl + 1, labelStyles.length - 1)],
          hasSubchannelsButton:
            lvl + 1 === maxDepth &&
            threadHasSubchannels(childItem, childThreadInfosMap),
        }));
      item.itemChildren.sort(compareCommunityDrawerItemData);
      queue = queue.concat(
        item.itemChildren.map(childItem => [childItem, lvl + 1]),
      );
    }
  }
  return result;
}

function threadHasSubchannels(
  threadInfo: ResolvedThreadInfo,