optmizie code, simplify aid generation

h-encore-auto/Util.cs

@@ -0,0 +1,65 @@
+using System;
+using System.Net;
+using System.Net.Http;
+using System.IO;
+using System.Windows.Markup;
+using System.Windows;
+
+namespace h_encore_auto
+{
+    public class Util
+    {
+        private static WebClient web = new WebClient();
+        private static HttpClient http = new HttpClient();
+
+        public static string GetEncKey(string aid)
+        //Thanks to noahc3 (https://github.com/noahc3/) for this. 
+        {
+            try
+            {
+                string page = http.GetStringAsync(Ref.urlCma + aid).Result;
+                return page.Substring(page.Length - 65, 64);
+            }
+            catch (Exception)
+            {
+                MessageBox.Show("Failed to get the CMA encryption key. Make sure your internet is connected and/or retry.");
+                return "";
+            }
+        }
+
+        public static void DeleteDirectory(string path)
+        {
+            foreach (string directory in Directory.GetDirectories(path))
+            {
+                DeleteDirectory(directory);
+            }
+            try
+            {
+                Directory.Delete(path, true);
+            }
+            catch (IOException)
+            {
+                Directory.Delete(path, true);
+            }
+            catch (UnauthorizedAccessException)
+            {
+                Directory.Delete(path, true);
+            }
+        }
+
+        public static void dlFile(string url, string filename)
+        {
+            using (WebClient client = new WebClient())
+            {
+                ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
+                client.DownloadFile(url, Ref.tempDir + filename);
+            }
+        }
+        public static void cleanup()
+        {
+            Util.DeleteDirectory(Ref.tempDir);
+            MessageBox.Show("Done.");
+            System.Environment.Exit(0);
+        }
+    }
+}