/// <summary>
        /// Constructor for Create action of a course
        /// </summary>
        /// <param name="id">Id of the instructor</param>
        public CourseInstructorViewModel(int id)
        {
            Instructor = new Instructor {Id = id};
            Course = new Course {
                OwnerId = Instructor.Id,
                Status = true,

            };
            GroupSummaries = new List<GroupSummary>();
            MessageInfos = new List<MessageInfo>();
        }
        /// <summary>
        /// Convert retrieved course for editing
        /// </summary>
        /// <param name="course">Course with owner</param>
        public CourseInstructorViewModel(Course course)
        {
            Course = course;
            Instructor = course.Owner;

            GroupSummaries =  course.Groups.Select(g => new GroupSummary
               (g)).ToList();

            MessageInfos = course.CourseMessages
                .Select(m => new MessageInfo(m)).ToList();

            StudentInfos = course.Students
                .Select(s=>new StudentInfo(s,courseId:course.Id))
                .ToList();
        }
        public void delete_applies_soft_delete()
        {
            //var repo = new CourseRepository(new MOOCollab2UOW());
            var repo = new CourseRepository(new TestDb());

            var testCourse = new Course { Id = 1, Status = true };

            //act
            repo.Delete(testCourse);

            var changedCourse = repo.CourseAndInstructorByCourseId(1);//get changed course
            //assert
            Assert.IsFalse(changedCourse.Status);
            Assert.IsNull(changedCourse.Groups.FirstOrDefault(g => g.Status == true));
        }