Update generation

- Move to global objects for files and validation
- Only write changed files
- Check images for changes before scaling
- Simplify code

WebsiteGenerator/Extensions/Data+Extensions.swift

@@ -0,0 +1,9 @@
+import Foundation
+
+extension Data {
+
+    func createFolderAndWrite(to url: URL) throws {
+        try url.ensureParentFolderExistence()
+        try write(to: url)
+    }
+}

WebsiteGenerator/Extensions/NSImage+Extensions.swift

@@ -0,0 +1,15 @@
+import Foundation
+import AppKit
+
+extension NSImage {
+
+    func scaledDown(to size: NSSize) -> NSImage {
+        guard self.size.width > size.width else {
+            return self
+        }
+        return NSImage(size: size, flipped: false) { (resizedRect) -> Bool in
+            self.draw(in: resizedRect)
+            return true
+        }
+    }
+}

WebsiteGenerator/Extensions/NSSize+Extensions.swift

@@ -0,0 +1,28 @@
+import Foundation
+
+extension NSSize {
+
+    func scaledDown(to desiredWidth: CGFloat) -> NSSize {
+        if width == desiredWidth {
+            return self
+        }
+
+        if width < desiredWidth {
+            // Don't scale larger
+            return self
+        }
+
+        let height = height * desiredWidth / width
+        return NSSize(width: desiredWidth, height: height)
+    }
+}
+
+extension NSSize {
+
+    var ratio: CGFloat {
+        guard height != 0 else {
+            return 0
+        }
+        return width / height
+    }
+}

WebsiteGenerator/Extensions/String+Extensions.swift

@@ -32,8 +32,16 @@ extension String {
         components(separatedBy: separator).last!
     }
 
+    /**
+     Insert the new content before the last occurence of the specified separator.
+
+     If the separator does not appear in the string, then the new content is simply appended.
+     */
     func insert(_ content: String, beforeLast separator: String) -> String {
         let parts = components(separatedBy: separator)
+        guard parts.count > 1 else {
+            return self + content
+        }
         return parts.dropLast().joined(separator: separator) + content + separator + parts.last!
     }
 
@@ -53,3 +61,10 @@ extension Substring {
             .components(separatedBy: end).first!
     }
 }
+
+extension String {
+
+    func createFolderAndWrite(to url: URL) throws {
+        try data(using: .utf8)!.createFolderAndWrite(to: url)
+    }
+}

WebsiteGenerator/Extensions/URL+Extensions.swift

@@ -0,0 +1,38 @@
+import Foundation
+
+extension URL {
+
+    func ensureParentFolderExistence() throws {
+        try deletingLastPathComponent().ensureFolderExistence()
+    }
+
+    func ensureFolderExistence() throws {
+        guard !exists else {
+            return
+        }
+        try FileManager.default.createDirectory(at: self, withIntermediateDirectories: true)
+    }
+
+    var isDirectory: Bool {
+        (try? resourceValues(forKeys: [.isDirectoryKey]))?.isDirectory == true
+    }
+
+    var exists: Bool {
+        FileManager.default.fileExists(atPath: path)
+    }
+
+    /**
+     Delete the file at the url.
+     */
+    func delete() throws {
+        try FileManager.default.removeItem(at: self)
+    }
+
+    func copy(to url: URL) throws {
+        if url.exists {
+            try url.delete()
+        }
+        try url.ensureParentFolderExistence()
+        try FileManager.default.copyItem(at: self, to: url)
+    }
+}