Extended Piped support

Model/Thumbnail.swift

@@ -4,6 +4,29 @@ import SwiftyJSON
 struct Thumbnail {
     enum Quality: String, CaseIterable {
         case maxres, maxresdefault, sddefault, high, medium, `default`, start, middle, end
+
+        var filename: String {
+            switch self {
+            case .maxres:
+                return "maxres"
+            case .maxresdefault:
+                return "maxresdefault"
+            case .sddefault:
+                return "sddefault"
+            case .high:
+                return "hqdefault"
+            case .medium:
+                return "mqdefault"
+            case .default:
+                return "default"
+            case .start:
+                return "1"
+            case .middle:
+                return "2"
+            case .end:
+                return "3"
+            }
+        }
     }
 
     var url: URL