FluxBB\Models\GroupRepository::getHierarchy PHP Method

    public function getHierarchy()
    {
        if ($this->cache->has('fluxbb.groups.hierarchy')) {
            return $this->cache->get('fluxbb.groups.hierarchy');
        }
        $allGroups = Group::orderBy('id')->get()->all();
        $keyedGroups = array();
        foreach ($allGroups as $group) {
            $keyedGroups[$group->id] = $group;
        }
        // Collect root groups and groups with parent by key
        $rootGroups = $groupsByParent = array();
        foreach ($keyedGroups as $key => $group) {
            if ($group->hasParent()) {
                $groupsByParent[$group->parent_group_id][] = $group;
            } else {
                $rootGroups[] = $group;
            }
        }
        // Now set up the children relationships for all leftover groups
        foreach ($groupsByParent as $parentGroupId => $subgroups) {
            $collection = new Collection($subgroups);
            $keyedGroups[$parentGroupId]->setRelation('children', $collection);
        }
        // Cache for 14 days
        $this->cache->put('fluxbb.groups.hierarchy', $rootGroups, 20160);
        return $rootGroups;
    }