Merge pull request #218 from kzi-nastava/feat/withdrawalrequest-class

[feat] Implement WithdrawalRequest functionality

LangLang/Core/Controller/AppController.cs

@@ -8,16 +8,18 @@ public class AppController
         public readonly CourseController CourseController;
         public readonly StudentController StudentController;
         public readonly EnrollmentRequestController EnrollmentRequestController;
+        public readonly WithdrawalRequestController WithdrawalRequestController;
         public readonly ExamSlotController ExamSlotController;
         public readonly LoginController LoginController;
         public AppController()
         {
-            this.TutorController = new TutorController();
-            this.CourseController = new CourseController();
-            this.StudentController = new StudentController();
-            this.EnrollmentRequestController = new EnrollmentRequestController();
-            this.ExamSlotController = new ExamSlotController();
-            this.LoginController = new LoginController(StudentController, TutorController);
+            TutorController = new();
+            CourseController = new();
+            StudentController = new();
+            EnrollmentRequestController = new();
+            WithdrawalRequestController = new();
+            ExamSlotController = new();
+            LoginController = new(StudentController, TutorController);
         }
 
 

LangLang/Core/Controller/WithdrawalRequestController.cs

@@ -0,0 +1,44 @@
+
+using LangLang.Core.Model;
+using LangLang.Core.Model.DAO;
+using LangLang.Core.Observer;
+using System.Collections.Generic;
+
+namespace LangLang.Core.Controller
+{
+    public class WithdrawalRequestController
+    {
+        private readonly WithdrawalRequestDAO _withdrawalRequests;
+
+        public WithdrawalRequestController()
+        {
+            _withdrawalRequests = new();
+        }
+
+        public List<WithdrawalRequest> GetAll()
+        {
+            return _withdrawalRequests.GetAllWithdrawalRequests();
+        }
+
+        public void Add(WithdrawalRequest withdrawalRequest)
+        {
+            _withdrawalRequests.Add(withdrawalRequest);
+        }
+
+        public void Delete(int id)
+        {
+            _withdrawalRequests.Remove(id);
+        }
+
+        public void Subscribe(IObserver observer)
+        {
+            _withdrawalRequests.Subscribe(observer);
+        }
+
+        public List<WithdrawalRequest> GetStudentRequests(int studentId, EnrollmentRequestController erController)
+        {
+            List<EnrollmentRequest> allEnrollmentRequests = erController.GetAll();
+            return _withdrawalRequests.GetStudentRequests(studentId, allEnrollmentRequests);
+        }
+    }
+}

LangLang/Core/Model/DAO/WithdrawalRequestDAO.cs

@@ -0,0 +1,72 @@
+
+using LangLang.Core.Observer;
+using LangLang.Core.Repository;
+using System.Collections.Generic;
+using System.Linq;
+
+
+namespace LangLang.Core.Model.DAO
+{
+    public class WithdrawalRequestDAO : Subject
+    {
+        private readonly Dictionary<int, WithdrawalRequest> _withdrawalRequests;
+        private readonly Repository<WithdrawalRequest> _repository;
+
+        public WithdrawalRequestDAO()
+        {
+            _repository = new Repository<WithdrawalRequest>("withdrawalRequests.csv");
+            _withdrawalRequests = _repository.Load();
+        }
+
+        private int GenerateId()
+        {
+            if (_withdrawalRequests.Count == 0) return 0;
+            return _withdrawalRequests.Keys.Max() + 1;
+        }
+
+        public WithdrawalRequest GetById(int id)
+        {
+            return _withdrawalRequests[id];
+        }
+
+        public List<WithdrawalRequest> GetAllWithdrawalRequests() 
+        {
+            return _withdrawalRequests.Values.ToList();
+        }
+
+        public WithdrawalRequest Add(WithdrawalRequest request)
+        {
+            request.Id= GenerateId();
+            _withdrawalRequests.Add(request.Id, request);
+            _repository.Save(_withdrawalRequests);
+            NotifyObservers();
+            return request;
+        }
+
+        public WithdrawalRequest? Remove(int id)
+        {
+            WithdrawalRequest? request = GetById(id);
+            if (request == null) return null;
+
+            _withdrawalRequests.Remove(request.Id);
+            _repository.Save(_withdrawalRequests);
+            NotifyObservers();
+            return request;
+        }
+
+        public List<WithdrawalRequest> GetStudentRequests(int studentId, List<EnrollmentRequest> allEnrollmentRequests)
+        {
+            List<WithdrawalRequest> studentRequests = new();
+            foreach (WithdrawalRequest request in GetAllWithdrawalRequests())
+            {
+                EnrollmentRequest enrollmentRequest = allEnrollmentRequests[request.EnrollmentRequestId];
+                if (enrollmentRequest.StudentId == studentId)
+                {
+                    studentRequests.Add(request);
+                }
+            }
+            return studentRequests;
+        }
+
+    }
+}

LangLang/Core/Model/WithdrawalRequest.cs

@@ -0,0 +1,65 @@
+
+using LangLang.Core.Model.Enums;
+using LangLang.Core.Repository.Serialization;
+using System;
+
+namespace LangLang.Core.Model
+{
+    // this class represents student's request to withdraw from course
+    public class WithdrawalRequest : ISerializable
+    {
+        public int Id { get; set; }
+        public int EnrollmentRequestId { get; set; }
+        public string Reason { get; set; }
+        public Status Status { get; private set; }
+        public DateTime RequestSentAt { get; set; }
+        public DateTime RequestReceivedAt { get; private set;}
+
+        public WithdrawalRequest() {}
+        public WithdrawalRequest(int id, int enrollmentRequestId, string reason, Status status, DateTime requestSentAt, DateTime requestReceivedAt)
+        {
+            Id = id;
+            EnrollmentRequestId = enrollmentRequestId;
+            Reason = reason;
+            Status = status;
+            RequestSentAt = requestSentAt;
+            RequestReceivedAt = requestReceivedAt;
+        }
+
+        public void UpdateStatus(Status status)
+        {
+            Status = status;
+            RequestReceivedAt = DateTime.Now;
+        }
+
+        public void FromCSV(string[] values)
+        {
+            try
+            {
+                RequestSentAt = DateTime.ParseExact(values[4], "yyyy-MM-dd", null);
+                RequestReceivedAt = DateTime.ParseExact(values[5], "yyyy-MM-dd", null);
+            }
+            catch
+            {
+                throw new FormatException("Date is not in the correct format.");
+            }
+
+            Id = int.Parse(values[0]);
+            EnrollmentRequestId = int.Parse(values[1]);
+            Reason = values[2];
+            Status = (Status)Enum.Parse(typeof(Status), values[3]);
+        }
+
+        public string[] ToCSV()
+        {
+            return new string[] {
+                Id.ToString(),
+                EnrollmentRequestId.ToString(),
+                Reason,
+                Status.ToString(),
+                RequestSentAt.ToString("yyyy-MM-dd"),
+                RequestReceivedAt.ToString("yyyy-MM-dd"),
+            };
+        }
+    }
+}