public AcademicOutcome HasGraduated(Diploma diploma, Student student)
{
var earnedCredits = 0;
var average = 0;
var requirements = requirementRepository.GetRequirementByDiploma(diploma);
earnedCredits = student.Courses
.Join(requirements,
course => course.Id,
req => req.Courses.First(),
(course, req) => new { Passed = course.Mark >= req.MinimumMark, Credits = req.Credits })
.Where(course => course.Passed)
.Select(course => course.Credits)
.Sum();
average = student.Courses.Select(c => c.Mark).Sum() / student.Courses.Length;
return(new AcademicOutcome(average, (diploma.Credits <= earnedCredits)));
}