Render text rect on macOS

Sources/PlaceholderKit/NSImage+Placeholder.swift

@@ -6,14 +6,26 @@
 //  Copyright © 2018 Shao Ping Lee. All rights reserved.
 //
 
-#if canImport(AppKit)
-import AppKit
+#if canImport(Cocoa)
+import Cocoa
 
 extension NSImage {
     static func image(withColor color: NSColor, size: CGSize) -> NSImage? {
         let image = NSImage(size: size)
+        let rect = CGRect(origin: .zero, size: size)
+
         image.lockFocus()
-        color.drawSwatch(in: NSMakeRect(0, 0, size.width, size.height))
+
+        // background
+        color.drawSwatch(in: rect)
+
+        // text
+        let text = PlaceholderBuilder().displayedText(size: size)
+        let attrs = PlaceholderBuilder().displayedTextAttributes()
+        let textRect = PlaceholderBuilder().textRect(imageSize: size)
+
+        // draw text
+        text.draw(in: textRect, withAttributes: attrs)
         image.unlockFocus()
         return image
     }

Sources/PlaceholderKit/PlaceholderKit.swift

@@ -10,10 +10,12 @@
 import AppKit
 public typealias Color = NSColor
 public typealias Image = NSImage
+public typealias Font = NSFont
 #else
 import UIKit
 public typealias Color = UIColor
 public typealias Image = UIImage
+public typealias Font = UIFont
 #endif
 
 public struct Placeholder {
@@ -35,24 +37,34 @@ public struct PlaceholderBuilder {
         return nil
     }
 
-    public init() {}
-}
+    // not platform specific
+    public func displayedTextAttributes() -> [NSAttributedString.Key: NSObject] {
+        let paragraphStyle = NSMutableParagraphStyle()
+        paragraphStyle.alignment = .center
 
-public struct PlaceholderSettings {
-    let size: CGSize
-    let background: BackgroundStyle
-    let showDimensionAsText: Bool
-    let convertDimensionToAspectRatio: Bool
+        let attrs = [NSAttributedString.Key.font: Font(name: "HelveticaNeue", size: 10)!, NSAttributedString.Key.paragraphStyle: paragraphStyle]
 
-    public init(size: CGSize,
-                background: BackgroundStyle,
-                showDimensionAsText: Bool,
-                convertDimensionToAspectRatio: Bool) {
-        self.size = size
-        self.background = background
-        self.showDimensionAsText = showDimensionAsText
-        self.convertDimensionToAspectRatio = convertDimensionToAspectRatio
+        return attrs
     }
+
+    public func displayedText(size: CGSize) -> String {
+        let string = "\(Int(size.width))x\(Int(size.height))"
+        return string
+    }
+
+    public func textRect(imageSize: CGSize) -> CGRect {
+        let attributedString = NSAttributedString(string: displayedText(size: imageSize),
+                                                  attributes: displayedTextAttributes())
+        let textSize = attributedString.size()
+        let rect =  CGRect(x: 0,
+                           y: (imageSize.height - textSize.height) / 2,
+                           width: imageSize.width,
+                           height: textSize.height)
+        return rect
+
+    }
+
+    public init() {}
 }
 
 public enum BackgroundStyle {

Sources/PlaceholderKit/UIImage+Placeholder.swift

@@ -18,17 +18,13 @@ extension UIImage {
             color.setFill()
             context.fill(rect)
 
-            // text style
-            let paragraphStyle = NSMutableParagraphStyle()
-            paragraphStyle.alignment = .center
-
-            let attrs = [NSAttributedString.Key.font: UIFont(name: "HelveticaNeue", size: 10)!, NSAttributedString.Key.paragraphStyle: paragraphStyle]
-
-            // display string
-            let string = "\(Int(size.width))x\(Int(size.height))"
+            // text
+            let text = PlaceholderBuilder().displayedText(size: size)
+            let attrs = PlaceholderBuilder().displayedTextAttributes()
+            let textRect = PlaceholderBuilder().textRect(imageSize: size)
 
             // draw text
-            string.draw(with: rect, options: .usesLineFragmentOrigin, attributes: attrs, context: nil)
+            text.draw(with: textRect, options: .usesLineFragmentOrigin, attributes: attrs, context: nil)
         }
 
         return image