seperated todoist and habitica api calls into services

Habitica.Todoist.Integration.Services/TodoistClientService.cs

@@ -0,0 +1,59 @@
+using Habitica.Todoist.Integration.Model.Todoist;
+using Newtonsoft.Json;
+using System;
+using System.Collections.Generic;
+using System.Net;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Habitica.Todoist.Integration.Services
+{
+    public class TodoistClientService
+    {
+        private string apiKey { get; set; }
+        private string baseUrl => "https://api.todoist.com/sync/v8/";
+
+        public TodoistClientService(string apiKey)
+        {
+            this.apiKey = apiKey;
+        }
+
+        public async Task<SyncResponse> GetUpdatedItems(string syncToken = "*")
+        {
+            using (var client = CreateWebClient())
+            {
+                var body = InitializeRequestBody();
+                body["sync_token"] = syncToken;
+                body["resource_types"] = "[\"items\"]";
+
+                var json = await client.UploadStringTaskAsync($"{baseUrl}sync", RequestBodyToString(body));
+                return JsonConvert.DeserializeObject<SyncResponse>(json);
+            }
+        }
+
+        private string RequestBodyToString(Dictionary<string, string> body)
+        {
+            var bodyStr = "";
+            foreach (var pair in body)
+                bodyStr += $"{pair.Key}={pair.Value}&";
+
+            return bodyStr;
+        }
+
+        private Dictionary<string, string> InitializeRequestBody()
+        {
+            var body = new Dictionary<string, string>();
+            body["token"] = apiKey;
+
+            return body;
+        }
+
+        private WebClient CreateWebClient()
+        {
+            var client = new WebClient();
+            client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
+
+            return client;
+        }
+    }
+}