/// <summary>
/// You should implement this function, such that all tests will pass.
/// Method that adds a teacher to a course with a given id.
/// The required attributes are given with a view model class.
/// </summary>
/// <param name="courseInstanceID">The ID of the course instance which the teacher will be registered to.</param>
/// <param name="model">The data which indicates which person should be added as a teacher, and in what role.</param>
/// <returns>Should return basic information about the person.</returns>
public PersonDTO AddTeacherToCourse(int courseInstanceID, AddTeacherViewModel model)
{
var course = _courseInstances.All().SingleOrDefault(x => x.ID == courseInstanceID);
var teacher = _persons.All().SingleOrDefault(x => x.SSN == model.SSN);
if(course == null || teacher == null)
{
throw new AppObjectNotFoundException();
}
var teacherInCourse = _teacherRegistrations.All().SingleOrDefault(x => x.CourseInstanceID == courseInstanceID && x.SSN == model.SSN);
if(teacherInCourse != null)
{
throw new AppValidationException("PERSON_ALREADY_REGISTERED_TEACHER_IN_COURSE");
}
var mainTeacher = _teacherRegistrations.All().SingleOrDefault(x => x.CourseInstanceID == courseInstanceID && x.Type == TeacherType.MainTeacher);
if (mainTeacher != null && model.Type == TeacherType.MainTeacher)
{
throw new AppValidationException("COURSE_ALREADY_HAS_A_MAIN_TEACHER");
}
TeacherRegistration tr = new TeacherRegistration
{
CourseInstanceID = courseInstanceID,
SSN = teacher.SSN,
Type = model.Type
};
_teacherRegistrations.Add(tr);
_uow.Save();
PersonDTO result = new PersonDTO
{
Name = teacher.Name,
SSN = teacher.SSN
};
return result;
}
/// <summary>
/// You should implement this function, such that all tests will pass.
/// </summary>
/// <param name="courseInstanceID">The ID of the course instance which the teacher will be registered to.</param>
/// <param name="model">The data which indicates which person should be added as a teacher, and in what role.</param>
/// <returns>Should return basic information about the person.</returns>
public PersonDTO AddTeacherToCourse(int courseInstanceID, AddTeacherViewModel model)
{
// 1. Validation
var courseInstance = _courseInstances.All().SingleOrDefault(x => x.ID == courseInstanceID);
if (courseInstance == null)
{
throw new AppObjectNotFoundException();
}
var person = _persons.All().SingleOrDefault(x => x.SSN == model.SSN);
if(person == null)
{
throw new AppObjectNotFoundException();
}
var registration = _teacherRegistrations.All().SingleOrDefault(x => x.SSN == model.SSN);
if(registration != null)
{
throw new AppValidationException("PERSON_ALREADY_REGISTERED_TEACHER_IN_COURSE");
}
// Check if model's type is a main teacher, if so and there already is a main teacher
// we throw an error.
if(model.Type == TeacherType.MainTeacher)
{
var teacherRegistrations = _teacherRegistrations.All().Where(x => x.CourseInstanceID == courseInstance.ID).ToList();
foreach(TeacherRegistration teacher in teacherRegistrations)
{
if(teacher.Type == TeacherType.MainTeacher)
{
throw new AppValidationException("COURSE_ALREADY_HAS_A_MAIN_TEACHER");
}
}
}
// Everything seems to be in order, create the entity model and
// assign the teacher to the course
var registrationEntity = new TeacherRegistration
{
CourseInstanceID = courseInstanceID,
SSN = model.SSN,
Type = model.Type
};
_teacherRegistrations.Add(registrationEntity);
_uow.Save();
// Creating the return object
var personDTO = new PersonDTO
{
Name = person.Name,
SSN = person.SSN
};
return personDTO;
}
/// <summary>
/// You should implement this function, such that all tests will pass.
/// </summary>
/// <param name="courseInstanceID">The ID of the course instance which the teacher will be registered to.</param>
/// <param name="model">The data which indicates which person should be added as a teacher, and in what role.</param>
/// <returns>Should return basic information about the person.</returns>
public PersonDTO AddTeacherToCourse(int courseInstanceID, AddTeacherViewModel model)
{
// Check if courseID is correct
var courseInstance = (from c in _courseInstances.All()
where c.ID == courseInstanceID
select c).SingleOrDefault();
if (courseInstance == null){
throw new AppObjectNotFoundException();
}
// Check if teacher SSN is in the system
var teacher = (from p in _persons.All()
where p.SSN == model.SSN
select p).SingleOrDefault();
if (teacher == null){
throw new AppObjectNotFoundException();
}
// Get the list of teachers assigned for this course
var teachersForCourse = (from tr in _teacherRegistrations.All()
where tr.CourseInstanceID == courseInstanceID
select tr).ToList();
// If the teacher being registered is a main teacher
// and the course already has a main teacher registered;
// throw an exception
if (model.Type == TeacherType.MainTeacher &&
teachersForCourse.Any(t => t.Type == TeacherType.MainTeacher))
{
throw new AppValidationException("COURSE_ALREADY_HAS_A_MAIN_TEACHER");
}
// If the teacher being registered is already registered as a
// teacher in the course; throw an exception
if (teachersForCourse.Any(t => t.SSN == model.SSN))
{
throw new AppValidationException("PERSON_ALREADY_REGISTERED_TEACHER_IN_COURSE");
}
// If all seems to be OK, register the teacher to the course
var teacherRegistration = new TeacherRegistration
{
SSN = model.SSN,
CourseInstanceID = courseInstanceID,
Type = model.Type
};
_teacherRegistrations.Add(teacherRegistration);
_uow.Save();
// Display the teacher that was added to the course
var personDTO = new PersonDTO
{
Name = teacher.Name,
SSN = teacher.SSN
};
return personDTO;
}
/// <summary>
/// You should implement this function, such that all tests will pass.
/// </summary>
/// <param name="courseInstanceID">The ID of the course instance which the teacher will be registered to.</param>
/// <param name="model">The data which indicates which person should be added as a teacher, and in what role.</param>
/// <returns>Should return basic information about the person.</returns>
public PersonDTO AddTeacherToCourse(int courseInstanceID, AddTeacherViewModel model)
{
var course = (from c in _courseInstances.All()
where c.ID == courseInstanceID
select c).SingleOrDefault();
// Make sure that the course exists
if (course == null)
{
throw new AppObjectNotFoundException();
}
var person = (from p in _persons.All()
where p.SSN == model.SSN
select p).SingleOrDefault();
// Make sure that the person exists
if (person == null)
{
throw new AppObjectNotFoundException();
}
if(model.Type == TeacherType.MainTeacher)
{
// Check if the course aldready has a main teacher
var teacherReg = (from tr in _teacherRegistrations.All()
where tr.CourseInstanceID == course.ID
&& tr.Type == TeacherType.MainTeacher
select tr).SingleOrDefault();
if(teacherReg != null)
{
throw new AppValidationException("COURSE_ALREADY_HAS_A_MAIN_TEACHER");
}
}
// Check if the person is already a teacher in the course
var alreadyTeacher = (from tr in _teacherRegistrations.All()
where tr.CourseInstanceID == course.ID
&& tr.SSN == person.SSN
select tr).SingleOrDefault();
if(alreadyTeacher != null)
{
throw new AppValidationException("PERSON_ALREADY_REGISTERED_TEACHER_IN_COURSE");
}
// Create TeacerRegistration entity
var teacherRegistration = new TeacherRegistration
{
SSN = person.SSN,
CourseInstanceID = course.ID,
Type = model.Type
};
// Add to database
_teacherRegistrations.Add(teacherRegistration);
_uow.Save();
var result = new PersonDTO
{
SSN = model.SSN,
Name = person.Name
};
return result;
}
