Clean code for file type detection

WebsiteGenerator.xcodeproj/project.pbxproj

@@ -22,7 +22,7 @@
 		E22E87AC289F1D3700E51191 /* Template.swift in Sources */ = {isa = PBXBuildFile; fileRef = E22E87AB289F1D3700E51191 /* Template.swift */; };
 		E22E87AE289F1E0000E51191 /* String+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = E22E87AD289F1E0000E51191 /* String+Extensions.swift */; };
 		E22E87B0289F221A00E51191 /* PrefilledTopBarTemplate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E22E87AF289F221A00E51191 /* PrefilledTopBarTemplate.swift */; };
-		E253C87728B767D50076B6D0 /* MediaType.swift in Sources */ = {isa = PBXBuildFile; fileRef = E253C87628B767D50076B6D0 /* MediaType.swift */; };
+		E253C87728B767D50076B6D0 /* ImageType.swift in Sources */ = {isa = PBXBuildFile; fileRef = E253C87628B767D50076B6D0 /* ImageType.swift */; };
 		E253C87A28B810090076B6D0 /* ImageOutput.swift in Sources */ = {isa = PBXBuildFile; fileRef = E253C87928B810090076B6D0 /* ImageOutput.swift */; };
 		E253C87C28B8BFB80076B6D0 /* FileSystem.swift in Sources */ = {isa = PBXBuildFile; fileRef = E253C87B28B8BFB80076B6D0 /* FileSystem.swift */; };
 		E253C87F28B8FBB00076B6D0 /* Data+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = E253C87E28B8FBB00076B6D0 /* Data+Extensions.swift */; };
@@ -38,6 +38,7 @@
 		E2C5A5E328A037F900102A25 /* PageTemplate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2C5A5E228A037F900102A25 /* PageTemplate.swift */; };
 		E2C5A5E528A03A6500102A25 /* BackNavigationTemplate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2C5A5E428A03A6500102A25 /* BackNavigationTemplate.swift */; };
 		E2C5A5E928A0451C00102A25 /* LocalizedSiteTemplate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2C5A5E828A0451C00102A25 /* LocalizedSiteTemplate.swift */; };
+		E2D4225128BD242200400E64 /* Configuration.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2D4225028BD242200400E64 /* Configuration.swift */; };
 		E2D55EDB28A2511D00B9453E /* OverviewSectionCleanTemplate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2D55EDA28A2511D00B9453E /* OverviewSectionCleanTemplate.swift */; };
 		E2F8FA1E28A539C500632026 /* MarkdownProcessor.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2F8FA1D28A539C500632026 /* MarkdownProcessor.swift */; };
 		E2F8FA2028AB72D900632026 /* PlaceholderTemplate.swift in Sources */ = {isa = PBXBuildFile; fileRef = E2F8FA1F28AB72D900632026 /* PlaceholderTemplate.swift */; };
@@ -83,7 +84,7 @@
 		E22E87AB289F1D3700E51191 /* Template.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Template.swift; sourceTree = "<group>"; };
 		E22E87AD289F1E0000E51191 /* String+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "String+Extensions.swift"; sourceTree = "<group>"; };
 		E22E87AF289F221A00E51191 /* PrefilledTopBarTemplate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PrefilledTopBarTemplate.swift; sourceTree = "<group>"; };
-		E253C87628B767D50076B6D0 /* MediaType.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MediaType.swift; sourceTree = "<group>"; };
+		E253C87628B767D50076B6D0 /* ImageType.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ImageType.swift; sourceTree = "<group>"; };
 		E253C87928B810090076B6D0 /* ImageOutput.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ImageOutput.swift; sourceTree = "<group>"; };
 		E253C87B28B8BFB80076B6D0 /* FileSystem.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FileSystem.swift; sourceTree = "<group>"; };
 		E253C87E28B8FBB00076B6D0 /* Data+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Data+Extensions.swift"; sourceTree = "<group>"; };
@@ -99,6 +100,7 @@
 		E2C5A5E228A037F900102A25 /* PageTemplate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PageTemplate.swift; sourceTree = "<group>"; };
 		E2C5A5E428A03A6500102A25 /* BackNavigationTemplate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BackNavigationTemplate.swift; sourceTree = "<group>"; };
 		E2C5A5E828A0451C00102A25 /* LocalizedSiteTemplate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LocalizedSiteTemplate.swift; sourceTree = "<group>"; };
+		E2D4225028BD242200400E64 /* Configuration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Configuration.swift; sourceTree = "<group>"; };
 		E2D55EDA28A2511D00B9453E /* OverviewSectionCleanTemplate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OverviewSectionCleanTemplate.swift; sourceTree = "<group>"; };
 		E2F8FA1D28A539C500632026 /* MarkdownProcessor.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MarkdownProcessor.swift; sourceTree = "<group>"; };
 		E2F8FA1F28AB72D900632026 /* PlaceholderTemplate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PlaceholderTemplate.swift; sourceTree = "<group>"; };
@@ -194,8 +196,9 @@
 				E2F8FA3928AE313A00632026 /* ValidationLog.swift */,
 				E253C87928B810090076B6D0 /* ImageOutput.swift */,
 				E253C87B28B8BFB80076B6D0 /* FileSystem.swift */,
-				E253C87628B767D50076B6D0 /* MediaType.swift */,
+				E253C87628B767D50076B6D0 /* ImageType.swift */,
 				E2F8FA2728ACD84400632026 /* VideoType.swift */,
+				E2D4225028BD242200400E64 /* Configuration.swift */,
 			);
 			path = Files;
 			sourceTree = "<group>";
@@ -346,8 +349,9 @@
 				E22E87A4289F0C7000E51191 /* SiteGenerator.swift in Sources */,
 				E22E87AC289F1D3700E51191 /* Template.swift in Sources */,
 				E22E87A0289F008200E51191 /* ThumbnailListGenerator.swift in Sources */,
+				E2D4225128BD242200400E64 /* Configuration.swift in Sources */,
 				E2F8FA3028AD450B00632026 /* PageState.swift in Sources */,
-				E253C87728B767D50076B6D0 /* MediaType.swift in Sources */,
+				E253C87728B767D50076B6D0 /* ImageType.swift in Sources */,
 				E22E87B0289F221A00E51191 /* PrefilledTopBarTemplate.swift in Sources */,
 				E22E87A8289F0E7B00E51191 /* PageGenerator.swift in Sources */,
 				E2C5A5E328A037F900102A25 /* PageTemplate.swift in Sources */,

WebsiteGenerator/Files/FileSystem.swift

@@ -261,7 +261,8 @@ final class FileSystem {
 
         // Ensure that image file is supported
         let ext = destinationUrl.pathExtension.lowercased()
-        guard MediaType.isProcessableImage(ext) else {
+        guard ImageType(fileExtension: ext) != nil else {
+            // TODO: This should never be reached, since extensions are checked before
             log.add(info: "Copying image", source: image.source)
             do {
                 let sourceUrl = input.appendingPathComponent(image.source)
@@ -303,7 +304,7 @@ final class FileSystem {
         }
 
         let destinationExtension = destinationUrl.pathExtension.lowercased()
-        guard let type = MediaType.supportedImage(destinationExtension) else {
+        guard let type = ImageType(fileExtension: destinationExtension)?.fileType else {
             log.add(error: "No image type for extension \(destinationExtension)",
                     source: destination)
             return

WebsiteGenerator/Files/ImageType.swift

@@ -0,0 +1,27 @@
+import Foundation
+import AppKit
+
+enum ImageType: CaseIterable {
+    case jpg
+    case png
+
+    init?(fileExtension: String) {
+        switch fileExtension {
+        case "jpg", "jpeg":
+            self = .jpg
+        case "png":
+            self = .png
+        default:
+            return nil
+        }
+    }
+
+    var fileType: NSBitmapImageRep.FileType {
+        switch self {
+        case .jpg:
+            return .jpeg
+        case .png:
+            return .png
+        }
+    }
+}

WebsiteGenerator/Files/MediaType.swift

@@ -1,39 +0,0 @@
-import Foundation
-import AppKit
-
-private let supportedImageExtensions: [String : NSBitmapImageRep.FileType] = [
-    "jpg" : .jpeg,
-    "jpeg" : .jpeg,
-    "png" : .png,
-]
-
-private let supportedVideoExtensions: Set<String> = [
-    "mp4", "mov", "m4v"
-]
-
-enum MediaType {
-    case image
-    case video
-    case file
-    case svg
-
-    init(fileExtension: String) {
-        if supportedImageExtensions[fileExtension] != nil {
-            self = .image
-        } else if supportedVideoExtensions.contains(fileExtension) {
-            self = .video
-        } else if fileExtension == "svg" {
-            self = .svg
-        } else {
-            self = .file
-        }
-    }
-
-    static func isProcessableImage(_ fileExtension: String) -> Bool {
-        supportedImage(fileExtension) != nil
-    }
-
-    static func supportedImage(_ fileExtension: String) -> NSBitmapImageRep.FileType? {
-        supportedImageExtensions[fileExtension]
-    }
-}

WebsiteGenerator/Files/VideoType.swift

@@ -1,6 +1,6 @@
 import Foundation
 
-enum VideoType: String {
+enum VideoType: String, CaseIterable {
     case mp4
     case m4v
 

WebsiteGenerator/Generators/MarkdownProcessor.swift

@@ -68,16 +68,16 @@ struct PageContentGenerator {
         let title = fileAndTitle.contains(" ") ? fileAndTitle.dropBeforeFirst(" ").nonEmpty : nil
 
         let fileExtension = file.lastComponentAfter(".").lowercased()
-        switch MediaType(fileExtension: fileExtension) {
+        if let _ = ImageType(fileExtension: fileExtension) {
-        case .image:
             return handleImage(page: page, file: file, rightTitle: title, leftTitle: alt)
-        case .video:
-            return handleVideo(page: page, file: file, optionString: alt)
-        case .svg:
-            return handleSvg(page: page, file: file, area: alt)
-        case .file:
-            return handleFile(page: page, file: file, fileExtension: fileExtension)
         }
+        if let _ = VideoType(rawValue: fileExtension) {
+            return handleVideo(page: page, file: file, optionString: alt)
+        }
+        if fileExtension == "svg" {
+            return handleSvg(page: page, file: file, area: alt)
+        }
+        return handleFile(page: page, file: file, fileExtension: fileExtension)
     }
 
     private func handleImage(page: Element, file: String, rightTitle: String?, leftTitle: String?) -> String {