/// <summary>
/// Creates a ClassViewModel for the given class
/// </summary>
/// <param name="class">Class to create view-model for</param>
public ClassViewModel(Class @class)
{
if(@class != null)
{
Id = @class.Id;
Title = @class.Title;
Prefix = @class.Prefix;
CourseNumber = @class.CourseNumber;
Section = @class.Section;
GradeDistribution = @class.GradeDistribution;
Teacher = new UserViewModel(@class.Teacher);
}
}
/// <summary>
/// Calculates and returns a students grade in a class
/// </summary>
/// <param name="student">To student to calculate a grade for</param>
/// <param name="class">The class that the student is enrolled in</param>
/// <returns></returns>
public async Task<float> GetStudentGradeAsync(ApplicationUser student, Class @class)
{
WorkItemManager workItemManager = new WorkItemManager(_db);
var workItems = await workItemManager.GetClassWorkItems(@class);
var total = 0.0f;
total += await GetAverageForType(student, workItems, WorkItemType.Exam, @class.GradeDistribution);
total += await GetAverageForType(student, workItems, WorkItemType.Homework, @class.GradeDistribution);
total += await GetAverageForType(student, workItems, WorkItemType.Other, @class.GradeDistribution);
total += await GetAverageForType(student, workItems, WorkItemType.Project, @class.GradeDistribution);
total += await GetAverageForType(student, workItems, WorkItemType.Quiz, @class.GradeDistribution);
return total;
}
/// <summary>
/// Deletes a students enrollment in a class
/// </summary>
/// <param name="class">The class the student is enrolled in or has applied for enrollment</param>
/// <param name="student">The student to unenroll from the class</param>
/// <returns>Null if the student is not enrolled in class. Otherwise, returns the
/// enrollment that was removed</returns>
/// <remarks>This clears all data associated with the student in this class and
/// cannot be undone</remarks>
public async Task<Enrollment> DropStudent(Class @class, ApplicationUser student)
{
// Check that the student is actually enrolled
var status = await _db.Enrollments.Where(e => e.Class.Id == @class.Id && e.Student.Id == student.Id).FirstOrDefaultAsync();
if(status == null)
{
return null;
}
// Delete all student related data
var scoreUnits = await _db.ScoreUnits.Where(sc => sc.Student.Id == student.Id).ToListAsync();
_db.ScoreUnits.RemoveRange(scoreUnits);
_db.Enrollments.Remove(status);
await _db.SaveChangesAsync();
return status;
}
/// <summary>
/// Enrolls a new student into the class
/// </summary>
/// <param name="class">Class to enroll the student in</param>
/// <param name="student">Student to enroll in a class</param>
/// <returns>Null if the an enrollment has already been created. Otherwise, the
/// enrollment that was just created.</returns>
public async Task<Enrollment> RequestEnrollment(Class @class, ApplicationUser student)
{
var status = await (from enrollment in _db.Enrollments
where enrollment.Student.Id == student.Id && enrollment.Class.Id == @class.Id
select enrollment).FirstOrDefaultAsync();
if(status != null)
{
return null;
}
// Create the enrollment as pending
Enrollment newEnroll = new Enrollment { Class = @class, Student = student, Pending = true };
_db.Enrollments.Add(newEnroll);
await _db.SaveChangesAsync();
return newEnroll;
}
/// <summary>
/// Creates a new class from the given binding model
/// </summary>
/// <param name="classBindingModel">Model containing the details of the class
/// to create</param>
/// <returns>Null if teacher could not be found. Otherwise, returns the
/// created class</returns>
public async Task<Class> CreateClass(CreateClassBindingModel classBindingModel)
{
var teacher = await _userManager.FindByNameAsync(classBindingModel.TeacherUserName);
if(teacher == null)
{
return null;
}
Class @class = new Class
{
Title = classBindingModel.Title,
Prefix = classBindingModel.Prefix,
CourseNumber = classBindingModel.CourseNumber,
Section = classBindingModel.Section,
Teacher = teacher,
GradeDistribution = classBindingModel.GradeDistribution
};
_db.Classes.Add(@class);
await _db.SaveChangesAsync();
return @class;
}
/// <summary>
/// Returns all students in a class (both pending and accepted)
/// </summary>
/// <param name="class">The class to return students for</param>
/// <returns></returns>
public async Task<IEnumerable<ApplicationUser>> GetAllStudents(Class @class)
{
return await _db.Enrollments
.Where(e => e.Class.Id == @class.Id)
.Select(e => e.Student).ToListAsync();
}
/// <summary>
/// Returns all students who have been accepted into a class
/// </summary>
/// <param name="class">The class to return students for</param>
/// <returns></returns>
public async Task<IEnumerable<ApplicationUser>> GetAcceptedStudents(Class @class)
{
return await _db.Enrollments.Where(e => e.Class.Id == @class.Id && e.Pending == false).Select(e => e.Student).ToListAsync();
}
/// <summary>
/// Returns all non-pending enrollments for the given class
/// </summary>
/// <param name="class">Class to return non-pending enrollments for</param>
/// <returns></returns>
public async Task<IEnumerable<Enrollment>> GetAcceptedEnrollmentsForClass(Class @class)
{
return await _db.Enrollments.Where(e => e.Class.Id == @class.Id && e.Pending == false).Include(e => e.Student).ToListAsync();
}
/// <summary>
/// Returns all enrollments both pending and not for a class
/// </summary>
/// <param name="class">The class to return the enrollments for</param>
/// <returns></returns>
public async Task<IEnumerable<Enrollment>> GetAllEnrollmentsForClass(Class @class)
{
return await _db.Enrollments.Where(e => e.Class.Id == @class.Id).Include(e => e.Student).ToListAsync();
}
/// <summary>
/// Returns all WorkItems that have been assigned in a class
/// </summary>
/// <param name="class">Class to return WorkItems for</param>
/// <returns></returns>
public async Task<IEnumerable<WorkItem>> GetClassWorkItems(Class @class)
{
if(@class == null)
{
return null;
}
return await Db.WorkItems.Where(e => e.Class.Id == @class.Id).Include(wi => wi.Class.Teacher).ToListAsync();
}
/// <summary>
/// Returns a list of announcements for the given class
/// </summary>
/// <param name="class"></param>
/// <returns></returns>
public async Task<IEnumerable<Announcement>> GetClassAnnouncements(Class @class)
{
return await _db.Announcements.Where(a => a.Class.Id == @class.Id).ToListAsync();
}