Catamaran/BoatCompareByType.cs

@@ -6,7 +6,52 @@ using System.Threading.Tasks;
 
 namespace Catamaran
 {
-    internal class BoatCompareByType
+    internal class BoatCompareByType : IComparer<IDrawingObject>
     {
+        public int Compare(IDrawingObject x, IDrawingObject y)
+        {
+            if (x == null && y == null)
+            {
+                return 0;
+            }
+            if (x == null && y != null)
+            {
+                return 1;
+            }
+            if (x != null && y == null)
+            {
+                return -1;
+            }
+            var xBoat = x as DrawingObjectBoat;
+            var yBoat = y as DrawingObjectBoat;
+            if (xBoat == null && yBoat == null)
+            {
+                return 0;
+            }
+            if (xBoat == null && yBoat != null)
+            {
+                return 1;
+            }
+            if (xBoat != null && yBoat == null)
+            {
+                return -1;
+            }
+            if (xBoat.GetBoat.GetType().Name != yBoat.GetBoat.GetType().Name)
+            {
+                if (xBoat.GetBoat.GetType().Name == "DrawingBoat")
+                {
+                    return -1;
+                }
+                return 1;
+            }
+            var speedCompare =
+           xBoat.GetBoat.Boat.Speed.CompareTo(yBoat.GetBoat.Boat.Speed);
+            if (speedCompare != 0)
+            {
+                return speedCompare;
+            }
+            return xBoat.GetBoat.Boat.Weight.CompareTo(yBoat.GetBoat.Boat.Weight);
+        }
     }
 }
+

Catamaran/DrawingObjectBoat.cs

@@ -14,9 +14,10 @@ namespace Catamaran
         {
             _catamaran = catamaran;
         }
+        public DrawingBoat GetBoat => _catamaran;
         public float Step => _catamaran?.Catamaran?.Step ?? 0;
         public (float Left, float Right, float Top, float Bottom)
-       GetCurrentPosition()
+        GetCurrentPosition()
         {
             return _catamaran?.GetCurrentPosition() ?? default;
         }