/**
   * @param ownerIdentifier
   * @param model
   * @param fbo
   * @param bindingResult
   * @return
   * @throws NotAVisitorException
   * @throws OwnerNotFoundException
   * @throws SchedulingException
   */
  @RequestMapping(method = RequestMethod.POST)
  protected String createAppointment(
      final ModelMap model,
      @PathVariable("ownerIdentifier") final String ownerIdentifier,
      @Valid @ModelAttribute(COMMAND_ATTR_NAME) final CreateAppointmentFormBackingObject fbo,
      BindingResult bindingResult)
      throws NotAVisitorException, OwnerNotFoundException, SchedulingException {
    CalendarAccountUserDetailsImpl currentUser =
        (CalendarAccountUserDetailsImpl)
            SecurityContextHolder.getContext().getAuthentication().getPrincipal();
    IScheduleVisitor visitor = currentUser.getScheduleVisitor();

    if (bindingResult.hasErrors()) {
      return "visitor/create-appointment-form";
    }

    IScheduleOwner selectedOwner = null;
    if (StringUtils.isNumeric(ownerIdentifier)) {
      Long ownerId = Long.parseLong(ownerIdentifier);
      selectedOwner = findOwnerForVisitor(visitor, ownerId);
    } else {
      PublicProfile profile = publicProfileDao.locatePublicProfileByKey(ownerIdentifier);
      if (null != profile) {
        selectedOwner = ownerDao.locateOwnerByAvailableId(profile.getOwnerId());
      }
    }

    if (null == selectedOwner) {
      throw new OwnerNotFoundException("no owner found for " + ownerIdentifier);
    }

    validateChosenStartTime(
        selectedOwner.getPreferredVisibleWindow(), fbo.getTargetBlock().getStartTime());

    AvailableBlock finalAppointmentBlock = fbo.getTargetBlock();
    if (fbo.isDoubleLengthAvailable()) {
      // check if selected meeting duration matches meeting durations maxLength
      // if it's greater, then we need to look up the next block in the schedule and attempt to
      // combine
      if (fbo.getSelectedDuration() == fbo.getMeetingDurations().getMaxLength()) {
        finalAppointmentBlock =
            availableScheduleDao.retrieveTargetDoubleLengthBlock(
                selectedOwner, finalAppointmentBlock.getStartTime());
      }
    }
    if (null == finalAppointmentBlock) {
      throw new SchedulingException("requested time is not available");
    }

    VEvent event =
        schedulingAssistantService.scheduleAppointment(
            visitor, selectedOwner, finalAppointmentBlock, fbo.getReason());
    model.put("event", event);
    model.put("owner", selectedOwner);
    model.put("ownerRemindersPreference", selectedOwner.getRemindersPreference());
    return "visitor/create-appointment-success";
  }
  /**
   * @param ownerIdentifier
   * @param weekStart
   * @param visitorUsername
   * @param model
   * @return
   * @throws NotAVisitorException
   * @throws CalendarUserNotFoundException
   */
  @RequestMapping(
      value = "/admin/schedule-debug/{ownerIdentifier}/visitor-conflicts.json",
      method = RequestMethod.GET)
  public View visitorConflicts(
      @PathVariable("ownerIdentifier") long ownerIdentifier,
      @RequestParam(value = "weekStart", required = false, defaultValue = "1") int weekStart,
      @RequestParam(value = "visitorUsername", required = true) String visitorUsername,
      final ModelMap model)
      throws NotAVisitorException, CalendarAccountNotFoundException {

    ICalendarAccount visitorAccount = this.calendarAccountDao.getCalendarAccount(visitorUsername);
    if (visitorAccount == null) {
      throw new NotAVisitorException(visitorUsername + " not found");
    }
    IScheduleVisitor visitor = this.visitorDao.toVisitor(visitorAccount);

    IScheduleOwner owner = ownerDao.locateOwnerByAvailableId(ownerIdentifier);
    if (owner == null) {
      throw new CalendarAccountNotFoundException("no owner found for id " + ownerIdentifier);
    }
    VisibleScheduleRequestConstraints requestConstraints =
        VisibleScheduleRequestConstraints.newInstance(owner, weekStart);

    List<AvailableBlock> visitorConflicts =
        this.schedulingAssistantService.calculateVisitorConflicts(
            visitor,
            owner,
            requestConstraints.getTargetStartDate(),
            requestConstraints.getTargetEndDate());
    List<String> conflictBlocks = new ArrayList<String>();
    SimpleDateFormat df = CommonDateOperations.getDateTimeFormat();
    for (AvailableBlock b : visitorConflicts) {
      conflictBlocks.add(df.format(b.getStartTime()));
    }
    model.addAttribute("conflicts", conflictBlocks);

    Calendar visitorCalendar =
        this.calendarDataDao.getCalendar(
            visitorAccount,
            requestConstraints.getTargetStartDate(),
            requestConstraints.getTargetEndDate());
    model.addAttribute("visitorCalendarData", visitorCalendar.toString());
    return new MappingJacksonJsonView();
  }