/// <summary>
/// RPC-method for adding a course to the schedule and for
/// adding the calling user to a course that someone else
/// has already added.
/// </summary>
/// <param name="courseId">Course ID</param>
/// <returns></returns>
public async Task AddCourse(string courseId)
{
using (var errorReporter = new ErrorReporter(s => CallingClient.Errors.ScheduleMessage = s))
{
var course = PaulRepository.Courses.FirstOrDefault(c => c.Id == courseId);
if (course == null)
{
errorReporter.Throw(
new ArgumentException("Course not found", nameof(courseId)),
UserErrorsViewModel.GenericErrorMessage);
}
var schedule = CallingClient.SharedScheduleVM.Schedule;
await CallingClient.SharedScheduleVM.TimetableHubSemaphore.WaitAsync();
try
{
var selectedCourse = schedule.SelectedCourses.FirstOrDefault(c => c.CourseId == courseId);
if (course.IsTutorial)
{
// The user has decided to select a pending tutorial or one
// that was already selected by another user, so remove all pending
// tutorials of this course
CallingClient.TailoredScheduleVM.RemovePendingTutorials(course, errorReporter);
// Remove user from other possibly selected tutorial
var parentCourse = schedule.SelectedCourses.First(sel => sel.Course.AllTutorials.SelectMany(it => it).Contains(course));
var otherSelectedTutorial = parentCourse.Course.AllTutorials
.FirstOrDefault(group => group.Contains(course))
?.FirstOrDefault(tut => schedule.SelectedCourses.Any(sel => Equals(tut, sel.Course) && sel.Users.Select(it => it.User).Contains(CallingClient.User)));
if (otherSelectedTutorial != null)
{
await RemoveUserFromCourse(otherSelectedTutorial.Id, acquireSemaphore : false);
}
//If the user hasn't selected the parent course of the tutorial, it will be added here
if (parentCourse.Users.All(u => u.User.Name != CallingClient.Name))
{
var connectedCourses = parentCourse.Course.ConnectedCourses.Concat(new[] { parentCourse.Course });
foreach (var c in connectedCourses)
{
await PaulRepository.AddUserToSelectedCourseAsync(schedule.SelectedCourses.First(s => s.CourseId == c.Id), CallingClient.User);
}
}
}
if (selectedCourse == null)
{
var connectedCourses = course.ConnectedCourses.Concat(new[] { course })
.Select(it => PaulRepository.CreateSelectedCourse(schedule, CallingClient.User, it))
.ToList();
await PaulRepository.AddCourseToScheduleAsync(schedule, connectedCourses);
AddTutorialsForCourse(courseId);
}
else if (selectedCourse.Users.All(u => u.User != CallingClient.User))
{
// The course has already been added to the schedule by someone else.
// Add the calling user to the selected course (if not yet done).
await PaulRepository.AddUserToSelectedCourseAsync(selectedCourse, CallingClient.User);
var connectedCourseIds = selectedCourse.Course.ConnectedCourses.Select(it => it.Id).ToList();
var selectedConnectedCourses = schedule.SelectedCourses
.Where(selCo => connectedCourseIds.Contains(selCo.CourseId));
foreach (var connectedCourse in selectedConnectedCourses)
{
await PaulRepository.AddUserToSelectedCourseAsync(connectedCourse, CallingClient.User);
}
}
UpdateAddedStateInSearchResultsAndCourseList(course, isAdded: true);
}
finally
{
CallingClient.SharedScheduleVM.TimetableHubSemaphore.Release();
}
UpdateTailoredViewModels();
}
}