Scaffold v1.0.0

Sources/EmbedderTool/FileDiscovery.swift

@@ -0,0 +1,49 @@
+import Foundation
+
+struct FileDiscovery {
+    func discoverEmbeddableFiles(in rootDirectory: URL) throws -> [EmbeddableFile] {
+        let rootComponents = standardizedComponents(of: rootDirectory)
+        return try enumerateRegularFiles(under: rootDirectory)
+            .filter(hasAllowedExtension)
+            .map { fileURL in
+                makeEmbeddableFile(at: fileURL, relativeToRootComponents: rootComponents)
+            }
+            .sorted(by: byRelativePath)
+    }
+
+    private func enumerateRegularFiles(under directory: URL) throws -> [URL] {
+        guard let enumerator = FileManager.default.enumerator(
+            at: directory,
+            includingPropertiesForKeys: [.isRegularFileKey],
+            options: [.skipsHiddenFiles]
+        ) else {
+            return []
+        }
+        return enumerator.compactMap { $0 as? URL }.filter(isRegularFile)
+    }
+
+    private func isRegularFile(_ url: URL) -> Bool {
+        (try? url.resourceValues(forKeys: [.isRegularFileKey]).isRegularFile) == true
+    }
+
+    private func hasAllowedExtension(_ url: URL) -> Bool {
+        FileExtensionAllowList.permits(url.pathExtension)
+    }
+
+    private func makeEmbeddableFile(
+        at fileURL: URL,
+        relativeToRootComponents rootComponents: [String]
+    ) -> EmbeddableFile {
+        let fileComponents = standardizedComponents(of: fileURL)
+        let relativeComponents = Array(fileComponents.dropFirst(rootComponents.count))
+        return EmbeddableFile(absoluteURL: fileURL, relativePathComponents: relativeComponents)
+    }
+
+    private func standardizedComponents(of url: URL) -> [String] {
+        url.standardizedFileURL.resolvingSymlinksInPath().pathComponents
+    }
+
+    private func byRelativePath(_ lhs: EmbeddableFile, _ rhs: EmbeddableFile) -> Bool {
+        lhs.relativePath.localizedStandardCompare(rhs.relativePath) == .orderedAscending
+    }
+}