public string GenerateAttendanceCode([FromBody] RequestAttendanceCodeDTO request)
{
bool isCodeUnique = false;
string attendanceCode = "";
while (!isCodeUnique) //Ensures the uniqueness of a generated code
{
attendanceCode = AttendanceCodeGenerator.GenerateAttendanceCode(); //Generates the code
if (AttendanceCodeComparer.CheckCodeUniqueness(_activeAttendanceCodes, attendanceCode))
{
isCodeUnique = true;
}
}
//Stores the code in memory
ActiveAttendanceCode activateCode = new ActiveAttendanceCode(_activeAttendanceCodes, attendanceCode, request);
return(activateCode.AttendanceCode);
}
/// <summary>
/// Initializes a new instance of ActiveAttendanceCode and sets its lifetime to 10 min.
/// </summary>
/// <param name="queue">An external ConcurrentQueue used to store the active codes</param>
/// <param name="attendanceCode">The active code to be stored in the provided ConcurrentQueue</param>
/// <param name="request">Information used to request the attendanceCode</param>
public ActiveAttendanceCode(ConcurrentQueue <ActiveAttendanceCode> queue, string attendanceCode, RequestAttendanceCodeDTO request)
{
_queue = queue;
_attendanceCode = attendanceCode;
_teacherId = request.TeacherId;
_subject = request.Subject;
_classes = request.Classes;
request.Modules.ForEach(module => _modules.Add(new Module(module)));
if (request.Coordinates != null)
{
_coordinates = new Coordinates(request.Coordinates);
}
_numberOfStudents = request.NumberOfStudents;
_duration = new CodeDuration(request.Duration);
queue.Enqueue(this);
_timer.Interval = _duration.Minutes * 60000;//Converts the duration from minutes to milliseconds and sets the timer.
//DeleteFromActiveCodes is called when the timer expires
_timer.Elapsed += new ElapsedEventHandler(DeleteFromActiveCodes);
_timer.Start();
}
