Add get unread messages count

Author: Suiram1701

API.Test/MessagesTests.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using static API.Test.AuthentificationTests;
+
+namespace API.Test;
+
+internal class MessagesTests
+{
+    [Test]
+    public void GetUnreadMessages()
+    {
+        Client.LoginAsync(s_Server, s_LoginName, s_UserName, s_Password).Wait();
+
+        Task<int> messages = Client.GetUnreadMessagesCountAsync();
+        messages.Wait();
+        if (messages.Result == 0)
+            Assert.Pass();
+        else
+            Assert.Fail();
+    }
+}

WebUntisAPI.Client/WebUntisClient.Messages.cs

@@ -0,0 +1,53 @@
+using Newtonsoft.Json.Linq;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Net.Http;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace WebUntisAPI.Client
+{
+    public partial class WebUntisClient
+    {
+        /// <summary>
+        /// Get the count of unread messages
+        /// </summary>
+        /// <param name="ct">Cancellation token</param>
+        /// <returns>The count of unread messages</returns>
+        /// <exception cref="ObjectDisposedException">Thrown when the instance was disposed</exception>
+        /// <exception cref="UnauthorizedAccessException">Thrown when you're logged in</exception>
+        /// <exception cref="HttpRequestException">Thrown when an error happened while the http request</exception>
+        public async Task<int> GetUnreadMessagesCountAsync(CancellationToken ct = default)
+        {
+            // Check for disposing
+            if (_disposedValue)
+                throw new ObjectDisposedException(GetType().FullName);
+
+            // Check if you logged in
+            if (!LoggedIn)
+                 throw new UnauthorizedAccessException("You're not logged in");
+
+            HttpRequestMessage request = new HttpRequestMessage()
+            {
+                Method = HttpMethod.Get,
+                RequestUri = new Uri(ServerUrl + "/WebUntis/api/rest/view/v1/messages/status")
+            };
+            SetRequestHeader(request.Headers, true);
+
+            HttpResponseMessage response = await _client.SendAsync(request, ct);
+
+            // Check cancellation token
+            if (ct.IsCancellationRequested)
+                return default;
+
+            // Verify response
+            if (response.StatusCode != HttpStatusCode.OK)
+                throw new HttpRequestException($"There was an error while the http request (Code: {response.StatusCode}).");
+
+            return JObject.Parse(await response.Content.ReadAsStringAsync()).Value<int>("unreadMessagesCount");
+        }
+    }
+}