Added GenerateSerial feature.

Runtime/Utils.cs

@@ -27,5 +27,22 @@ namespace UltraCombos.Frozen.RoyalGallery
             string hex = color.r.ToString("X2") + color.g.ToString("X2") + color.b.ToString("X2");
             return hex;
         }
+
+        public static string GenerateSerial(int dev_id, string page_id)
+        {
+            string dev_sid = dev_id.ToString("X");
+            string date = System.DateTime.Now.ToString("HHmmss");
+            string res_sid = page_id;
+            try
+            {
+                res_sid = System.Int32.Parse(res_sid).ToString("X");
+            }
+            catch (System.FormatException)
+            {
+                Debug.LogWarning($"GenerateSerial: rid={res_sid} is not number.");
+            }
+
+            return $"{date}{dev_sid}{res_sid}";
+        }
     }
 }