public async Task <StudentsGradeByInstructor> ListGradesGiven(int instructorId)
{
var instructor = await _instructorRepository.GetById(instructorId);
if (instructor == null)
{
throw new ArgumentException($"There's no instructor with the instructorId = {instructorId}");
}
var enrollments = await _enrollmentRepository.GetByInstructorId(instructorId);
if (!enrollments.Any())
{
throw new Exception($"The instructor with the Id = {instructorId} never gave a grade");
}
var result = new StudentsGradeByInstructor
{
Instructor = $"{instructor.FirstName} {instructor.LastName}",
InstructorId = instructorId
};
foreach (var enrollment in enrollments)
{
result.GradeXStudentXCourse.Add(
new StudentsGradeInfo
{
Grade = enrollment.Grade,
StudentId = enrollment.StudentId,
Student = $"{enrollment.Student.FirstName} {enrollment.Student.LastName}",
CourseId = enrollment.CourseId,
Course = enrollment.Course.Title
}
);
}
return(result);
}
