add pickMarginIn to UIDevice for a better use case

Yep/Configs/YepConfig.swift

@@ -99,16 +99,7 @@ class YepConfig {
 
     struct SocialWorkGithub {
         struct Repo {
-            static let leftEdgeInset: CGFloat = {
-                switch UIDevice.screenWidthModel {
-                case .Classic:
-                    return 20
-                case .Bigger:
-                    return 40
-                case .BiggerPlus:
-                    return 40
-                }
-                }()
+            static let leftEdgeInset = UIDevice.pickMarginIn([20, 40, 40])
             static let rightEdgeInset = leftEdgeInset
         }
     }

Yep/Extensions/UIDevice+Yep.swift

@@ -10,10 +10,16 @@ import UIKit
 
 extension UIDevice {
 
-    enum ScreenWidthModel {
-        case Classic
+    enum ScreenWidthModel: Int {
+        case Classic = 0
         case Bigger
         case BiggerPlus
+
+        static var caseCount: Int {
+            var max: Int = 0
+            while let _ = self(rawValue: ++max) {}
+            return max
+        }
     }
 
     static let screenWidthModel: ScreenWidthModel = {
@@ -33,4 +39,19 @@ extension UIDevice {
 
         return .Bigger // Default
         }()
+
+    class func pickMarginIn(margins: [CGFloat]) -> CGFloat {
+
+        if margins.count < ScreenWidthModel.caseCount {
+            println("Warning: NOT enough margins")
+
+            if margins.count > 0 {
+                return margins[0]
+            } else {
+                return 0
+            }
+        }
+
+        return margins[screenWidthModel.rawValue]
+    }
 }