public void build() {
        groups = TreeMultimap.create(String::compareToIgnoreCase, Comparator.comparing(TaskDetails::getPath));
        for (TaskReportModel project : projects) {
            for (String group : project.getGroups()) {
                if (isVisible(group)) {
                    for (final TaskDetails task : project.getTasksForGroup(group)) {
                        groups.put(group, mergeTasksWithSameName ? mergedTaskDetails(task) : task);