/// <summary>
/// Removes the calling user from the specified selected course.
/// If after the removal no other user has selected the course,
/// the course is removed from the schedule.
/// </summary>
/// <remarks>
/// If the user has not selected the course with the specified ID,
/// nothing happens.
/// </remarks>
/// <param name="courseId">Course ID</param>
/// <returns></returns>
public async Task RemoveUserFromCourse(string courseId, bool acquireSemaphore = true)
{
using (var errorReporter = new ErrorReporter(s => CallingClient.Errors.ScheduleMessage = s))
{
if (PaulRepository.Courses.All(c => c.Id != courseId))
{
errorReporter.Throw(
new ArgumentException("Course not found", nameof(courseId)),
UserErrorsViewModel.GenericErrorMessage);
}
var schedule = CallingClient.SharedScheduleVM.Schedule;
var selectedCourse = schedule.SelectedCourses
.FirstOrDefault(c => c.CourseId == courseId);
if (selectedCourse == null)
{
errorReporter.Throw(
new ArgumentException("Course not found in the schedule!"),
UserErrorsViewModel.GenericErrorMessage);
}
var selectedConnectedCourses = schedule.SelectedCourses
.Where(sel => selectedCourse.Course.ConnectedCourses.Any(it => it.Id == sel.CourseId))
.ToList();
if (acquireSemaphore)
{
await CallingClient.SharedScheduleVM.TimetableHubSemaphore.WaitAsync();
}
try
{
var selectedCourseUser = selectedCourse.Users.FirstOrDefault(o => o.User == CallingClient.User);
//Find selected Tutorials
var selectedTutorials = schedule.SelectedCourses
.Where(sel => selectedCourse.Course.Tutorials
.Concat(selectedConnectedCourses.SelectMany(s => s.Course.Tutorials))
.Any(it => it.Id == sel.CourseId))
.ToList();
if (selectedCourseUser != null)
{
// Remove user from selected courses
foreach (var sel in selectedConnectedCourses.Concat(selectedTutorials).Concat(new[] { selectedCourse }))
{
await PaulRepository.RemoveUserFromSelectedCourseAsync(sel, selectedCourseUser);
}
}
if (!selectedCourse.Users.Any())
{
var firstTutorials = selectedCourse.Course.Tutorials.Take(1)
.Concat(selectedConnectedCourses.SelectMany(s => s.Course.Tutorials.Take(1)));
// Remove all Pending Tutorials from all TailoredSchedules
foreach (var user in CallingClient.SharedScheduleVM.Users)
{
foreach (var t in firstTutorials)
{
user.TailoredScheduleVM.RemovePendingTutorials(t, errorReporter);
}
}
// The course is no longer selected by anyone
// -> Remove the whole course from schedule
foreach (var sel in selectedConnectedCourses.Concat(selectedTutorials).Concat(new[] { selectedCourse }))
{
await PaulRepository.RemoveCourseFromScheduleAsync(schedule, sel.CourseId);
}
}
UpdateAddedStateInSearchResultsAndCourseList(selectedCourse.Course, isAdded: false);
UpdateTailoredViewModels();
}
finally
{
if (acquireSemaphore)
{
CallingClient.SharedScheduleVM.TimetableHubSemaphore.Release();
}
}
}
}
/// <summary>
/// RPC-method for removing a course from the schedule
/// </summary>
/// <param name="courseId"></param>
/// <returns></returns>
public async Task RemoveCourse(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 (selectedCourse != null)
{
//Find selected Tutorials
var selectedTutorials = schedule.SelectedCourses
.Where(sel => selectedCourse.Course.Tutorials.Any(it => it.Id == sel.CourseId))
.Select(s => s.Course)
.ToList();
var courses = selectedCourse.Course.ConnectedCourses
.Concat(selectedTutorials)
.Concat(new[] { selectedCourse.Course });
foreach (var course1 in courses)
{
try
{
if (course1.Tutorials.Any())
{
// Remove all pending tutorials from all TailoredSchedules
foreach (var user in CallingClient.SharedScheduleVM.Users)
{
user.TailoredScheduleVM.RemovePendingTutorials(course1.Tutorials.FirstOrDefault(), errorReporter);
}
}
await PaulRepository.RemoveCourseFromScheduleAsync(schedule, course1.Id);
UpdateAddedStateInSearchResultsAndCourseList(course1, isAdded: false);
}
catch (NullReferenceException e)
{
// This is just for purposes of compatibility
// with development versions. Can be safely removed
// after product launch
PaulRepository.AddLog(e.Message, FatalityLevel.Normal, typeof(TimetableHub).Name);
}
}
UpdateTailoredViewModels();
}
else if (course.IsTutorial)
{
// The user has decided to remove a tutorial before joining one
CallingClient.TailoredScheduleVM.RemovePendingTutorials(course, errorReporter);
UpdateTailoredViewModels();
}
else
{
errorReporter.Throw(
new ArgumentException("Course not found in the schedule!"),
UserErrorsViewModel.GenericErrorMessage);
}
}
finally
{
CallingClient.SharedScheduleVM.TimetableHubSemaphore.Release();
}
}
}