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User.cs

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+using System;
+using System.Collections.Generic;
+using System.Dynamic;
+using System.Net.Mail;
+using System.Runtime.CompilerServices;
+using System.Text;
+
+namespace First_week
+{
+    internal class User
+    {
+        public Guid Id { get; }
+        public string Name { get; private set; }
+        public string Surname { get; private set; }
+        public MailAddress? Email { get; private set; }
+        public DateOnly Date { get; private set; }
+        public bool IsActive { get; private set; }
+
+        public User(string name, string surname, MailAddress email, DateOnly date)
+        {
+            if (name == null || name.Length > 100)
+                throw new Exception("Incorrect name");
+
+            if (surname == null || surname.Length > 100)
+                throw new Exception("Incorrect surname");
+
+            if (date.CompareTo(DateOnly.FromDateTime(DateTime.Now)) > 0)
+                throw new Exception("Incorrect birthdate");
+
+            Id = Guid.NewGuid();
+            Name = name;
+            Surname = surname;
+            Email = email;
+            Date = date;
+            IsActive = true;
+        }
+
+        public string GetFullName()
+        {
+            return ($"{Surname} {Name}");
+        }
+
+        public void UpdateEmail(MailAddress newMail)
+        {
+            Email = newMail;
+        }
+
+        public void UpdateDate(DateOnly date)
+        {
+            if (date.CompareTo(DateOnly.FromDateTime(DateTime.Now)) > 0)
+                throw new Exception("Wrong date");
+
+            Date = date;
+        }
+
+        public void Deactivate()
+        {
+            IsActive = false;
+        }
+    }
+}