// FIXME this should be stored in Couch
// along with first access to the task
public static Version resolveVersion(
final Task task,
final int anchor, final int step,
final Collection<String> studentIds, final String studentId
) {
final List<Version> versionsEff =
filterPrivateVersions(task);
final ArrayList<String> studIds =
new ArrayList<String>(studentIds);
Collections.sort(studIds);
final int studIdx = studIds.indexOf(studentId);
final int vSize = versionsEff.size();
final int verIdx = (anchor + (vSize + step) * studIdx) % vSize;
return versionsEff.get(verIdx);
}
public static List<Version> filterPrivateVersions(Task task) {
if (task.getVersions().isEmpty()) {
throw new IllegalStateException(
"task has no versions: " + task.getId()
);
}
final List<Version> versions = new ArrayList<Version>(
task.getVersions().values()
);
final List<Version> versionsPriv = new ArrayList<Version>(
versions
);
for (
Iterator<Version> verIt = versionsPriv.iterator();
verIt.hasNext();
) {
if (verIt.next().isShared()) {
verIt.remove();
}
}
return versionsPriv.isEmpty() ? versions : versionsPriv;
}