/**
   * Displays a Discussion Thread page
   *
   * <p>- Requires a cookie for the session user - Requires a threadId request parameter for the
   * HTTP GET
   *
   * @param req The HTTP Request
   * @param res The HTTP Response
   */
  public void discussionAction(HttpServletRequest req, HttpServletResponse res) {
    // Ensure there is a cookie for the session user
    if (AccountController.redirectIfNoCookie(req, res)) return;

    Map<String, Object> viewData = new HashMap<>();

    if (req.getMethod() == HttpMethod.Get) {

      // Get the thread
      GroupManager gm = new GroupManager();
      int threadId = Integer.parseInt(req.getParameter("threadId"));
      DiscussionManager discussionManager = new DiscussionManager();
      DiscussionThread thread = discussionManager.getThread(threadId);
      thread.setGroup(gm.get(thread.getGroupId()));
      thread.setPosts(discussionManager.getPosts(threadId));

      // get documents for the thread
      DocumentManager docMan = new DocumentManager();
      viewData.put("documents", docMan.getDocumentsForThread(threadId));

      viewData.put("thread", thread);
      viewData.put("title", "Discussion: " + thread.getThreadName());
      view(req, res, "/views/group/DiscussionThread.jsp", viewData);
    } else {
      httpNotFound(req, res);
    }
  }
 private void displayDiscussionThread(DiscussionThread thread) {
   view.removeAllNotes();
   final List<Note> rootNotes = new ArrayList<Note>(thread.getRootNotes());
   Collections.sort(
       rootNotes,
       new Comparator<Note>() {
         @Override
         public int compare(Note o1, Note o2) {
           return (int) -(o1.getTimestamp() - o2.getTimestamp());
         }
       });
   for (Note rootNote : rootNotes) {
     appendNote(rootNote, 0, thread);
   }
   currentNoteIds.clear();
   currentNoteIds.addAll(thread.getNoteIds());
 }
 private void appendNote(Note note, int depth, DiscussionThread discussionThread) {
   NoteContainerPresenter noteContainerPresenter =
       new NoteContainerPresenter(new NoteContainerViewImpl());
   noteContainerPresenter.setNote(note, discussionThread);
   view.addNote(noteContainerPresenter, depth);
   for (Note childNote : discussionThread.getReplies(note.getNoteId())) {
     appendNote(childNote, depth + 1, discussionThread);
   }
 }
  /**
   * Displays the Create Discussion page for a HTTP Get, or creates a Discussion Thread for a HTTP
   * Post
   *
   * <p>- Requires a cookie for the session user - Requires a groupId request parameter for a GET -
   * Requires a groupId and threadName request parameter for a POST - Requires a document request
   * part for a POST
   *
   * @param req The HTTP Request
   * @param res The HTTP Response
   */
  public void createDiscussionAction(HttpServletRequest req, HttpServletResponse res) {
    // Ensure there is a cookie for the session user
    if (AccountController.redirectIfNoCookie(req, res)) return;

    Map<String, Object> viewData = new HashMap<>();

    if (req.getMethod() == HttpMethod.Get) {
      viewData.put("title", "Create Discussion");
      viewData.put("groupId", req.getParameter("groupId"));

      view(req, res, "/views/group/CreateDiscussion.jsp", viewData);
      return;
    } else if (req.getMethod() == HttpMethod.Post) {
      // save discussion
      GroupManager groupMan = new GroupManager();
      DiscussionThread thread = new DiscussionThread();
      int groupId = Integer.parseInt(req.getParameter("groupId"));
      thread.setGroupId(groupId);
      thread.setGroup(groupMan.get(groupId));
      thread.setThreadName(req.getParameter("threadName"));

      DiscussionManager dm = new DiscussionManager();
      dm.createDiscussion(thread);

      try {
        Part documentPart = req.getPart("document");

        // if we have a document to upload
        if (documentPart.getSize() > 0) {
          String uuid = DocumentController.saveDocument(this.getServletContext(), documentPart);
          Document doc = new Document();
          doc.setDocumentName(getFileName(documentPart));
          doc.setDocumentPath(uuid);
          doc.setVersionNumber(1);
          doc.setThreadId(thread.getId());
          doc.setGroupId(thread.getGroupId());

          DocumentManager docMan = new DocumentManager();
          docMan.createDocument(doc);

          // Get uploading User
          HttpSession session = req.getSession();
          Session userSession = (Session) session.getAttribute("userSession");
          User uploader = userSession.getUser();

          // Create a notification to all in the group
          NotificationManager notificationMan = new NotificationManager();
          groupMan = new GroupManager();
          List<User> groupUsers = groupMan.getGroupUsers(groupId);

          for (User u : groupUsers) {
            Notification notification =
                new Notification(
                    u.getId(),
                    u,
                    groupId,
                    null,
                    "User " + uploader.getFullName() + " has uploaded a document",
                    "/document/document?documentId=" + doc.getId());

            notificationMan.createNotification(notification);
          }
        }
      } catch (Exception e) {
        logger.log(Level.SEVERE, "Document save error", e);
      }

      redirectToLocal(req, res, "/group/discussion/?threadId=" + thread.getId());
      return;
    }
    httpNotFound(req, res);
  }