private Studies GetStudies(string name)
{
using (var db = new s18838Context())
{
return(db.Studies.Where(s => s.Name == name).SingleOrDefault());
}
}
public void removeStudent(string indexNumber)
{
using (var db = new s18838Context())
{
var student = db.Student.Where(s => s.IndexNumber == indexNumber).SingleOrDefault();
db.Student.Remove(student);
db.SaveChanges();
}
}
public IEnumerable <Enrollment> GetEnrollments(string indexNumber)
{
using (var db = new s18838Context())
{
return(db.Student
.Where(s => s.IndexNumber == indexNumber)
.Select(e => e.IdEnrollmentNavigation));
}
}
private Enrollment GetLastEnrollmentForStudy(int id)
{
using (var db = new s18838Context())
{
return(db.Enrollment
.Where(e => e.IdStudy == id && e.Semester == 1)
.FirstOrDefault());
}
}
public string CheckRefreshToken(string refreshToken)
{
using (var db = new s18838Context())
{
return(db.Token
.Where(t => t.RefreshToken == refreshToken)
.Select(e => e.IndexNumber)
.FirstOrDefault());
}
}
public string GetSalt(string indexNumber)
{
using (var db = new s18838Context())
{
return(db.Student
.Where(s => s.IndexNumber == indexNumber)
.Select(e => e.Salt)
.SingleOrDefault());
}
}
public bool CheckIfStudentExists(string indexNumber)
{
using (var db = new s18838Context())
{
return(db.Student
.Where(s => s.IndexNumber == indexNumber)
.Select(e => true)
.FirstOrDefault());
}
}
public void DeleteRefreshToken(string refreshToken)
{
using (var db = new s18838Context())
{
var token = db.Token
.Where(t => t.RefreshToken == refreshToken)
.SingleOrDefault();
db.Token.Remove(token);
db.SaveChanges();
}
}
public void SaveRefreshToken(string refreshToken, string indexNumber)
{
using (var db = new s18838Context())
{
var token = new Token
{
IndexNumber = indexNumber,
RefreshToken = refreshToken
};
db.Token.Add(token);
db.SaveChanges();
}
}
private Enrollment GetEnrollment(string name, int semester)
{
using (var db = new s18838Context())
{
return(db.Enrollment
.Where(e => e.Semester == semester)
.Join(
db.Studies.Where(s => s.Name == name),
e => e.IdStudy, s => s.IdStudy,
(e, _) => e
).SingleOrDefault());
}
}
public void modifyStudent(string indexNumber, Student student)
{
using (var db = new s18838Context())
{
var s = db.Student.Where(s => s.IndexNumber == indexNumber).SingleOrDefault();
s.IndexNumber = student.IndexNumber;
s.FirstName = student.FirstName;
s.BirthDate = student.BirthDate;
s.IdEnrollment = student.IdEnrollment;
s.Salt = student.Salt;
s.Password = student.Password;
db.SaveChanges();
}
}
public Enrollment EnrollStudent(EnrollStudentRequest request)
{
using (var db = new s18838Context()) {
if (request.Studies == null ||
request.BirthDate == null ||
request.FirstName == null ||
request.IndexNumber == null ||
request.LastName == null)
{
throw new Exception();
}
using (var transaction = db.Database.BeginTransaction())
{
var study = GetStudies(request.Studies);
if (study == null)
{
transaction.Rollback();
throw new Exception();
}
Enrollment enrollment = GetLastEnrollmentForStudy(study.IdStudy);
if (enrollment == null)
{
enrollment = new Enrollment()
{
Semester = 1,
IdStudy = study.IdStudy,
StartDate = DateType.FromString(DateTime.Now.ToString("MM.dd.yyyy"))
};
SaveEnrollment(db, enrollment);
}
if (CheckIfStudentExists(request.IndexNumber))
{
transaction.Rollback();
throw new Exception();
}
var student = new Student()
{
IndexNumber = request.IndexNumber,
FirstName = request.FirstName,
LastName = request.LastName,
BirthDate = DateType.FromString(request.BirthDate),
IdEnrollment = IntegerType.FromObject(enrollment.IdEnrollment)
};
SaveStudent(db, student);
transaction.Commit();
return(enrollment);
}
}
}
public Enrollment PromoteStudents(PromoteStudentsRequest request)
{
using (var db = new s18838Context())
{
var enrollment = GetEnrollment(request.Studies, request.Semester);
if (enrollment == null)
{
throw new Exception();
}
db.Database.ExecuteSqlRaw("exec PromoteStudents @Studies @Semester", request.Studies, request.Semester);
enrollment.Semester++;
return(enrollment);
}
}
public bool LogIn(LoginCredentials loginCredentials)
{
using (var db = new s18838Context())
{
var salt = GetSalt(loginCredentials.Login);
var valueBytes =
KeyDerivation.Pbkdf2(
loginCredentials.Password,
Encoding.UTF8.GetBytes(salt),
KeyDerivationPrf.HMACSHA512,
1000,
256 / 8
);
var password = Convert.ToBase64String(valueBytes);
return(db.Student
.Where(s => s.IndexNumber == loginCredentials.Login && s.Password == password)
.Select(e => true)
.SingleOrDefault());
}
}
public IEnumerable <Student> GetStudents()
{
using (var db = new s18838Context()) {
return(db.Student.ToList());
}
}
private void SaveStudent(s18838Context db, Student student)
{
db.Student.Add(student);
db.SaveChanges();
}
private void SaveEnrollment(s18838Context db, Enrollment enrollment)
{
db.Enrollment.Add(enrollment);
db.SaveChanges();
}
