Enable pruning downloaded models

Sources/LocalLLMClientCore/LLMSession.swift

@@ -302,6 +302,33 @@ public extension LLMSession {
         public func downloadModel(onProgress: @Sendable @escaping (Double) async -> Void = { _ in }) async throws {
             try await downloader.download(onProgress: onProgress)
         }
+
+        public static func pruneModels(in url: URL = FileDownloader.defaultRootDestination, excluding: [Model] = []) throws {
+            guard let enumerator = FileManager.default.enumerator(at: url, includingPropertiesForKeys: [.isDirectoryKey], options: [.skipsPackageDescendants]) else { return }
+
+            let excludingNormalized: Set<URL> = Set(excluding.compactMap { model -> URL? in
+                if let model = model as? LLMSession.DownloadModel {
+                    return model.modelPath.resolvingSymlinksInPath().standardizedFileURL
+                }
+                if let model = model as? LLMSession.LocalModel {
+                    return model.modelPath.resolvingSymlinksInPath().standardizedFileURL
+                }
+                return nil
+            })
+
+            for case let fileURL as URL in enumerator {
+                if excludingNormalized.contains(fileURL.resolvingSymlinksInPath().standardizedFileURL) {
+                    enumerator.skipDescendants()
+                    continue
+                }
+
+                if (try fileURL.resourceValues(forKeys: [.isDirectoryKey])).isDirectory == false {
+                    try FileManager.default.removeItem(at: fileURL)
+                }
+            }
+
+            try url.removeEmptyFolders()
+        }
     }
 
     struct LocalModel: Model {

Sources/LocalLLMClientUtility/URL+.swift

@@ -18,4 +18,17 @@ package extension URL {
         return url
 #endif
     }
+
+    func removeEmptyFolders() throws {
+        guard isFileURL else { return }
+
+        let contents = try FileManager.default.contentsOfDirectory(at: self, includingPropertiesForKeys: [.isDirectoryKey])
+        let subdirectories = try contents.filter { try $0.resourceValues(forKeys: [.isDirectoryKey]).isDirectory ?? false }
+
+        for subdirectory in subdirectories { try subdirectory.removeEmptyFolders() }
+
+        guard try FileManager.default.contentsOfDirectory(at: self, includingPropertiesForKeys: nil).isEmpty else { return }
+
+        try FileManager.default.removeItem(at: self)
+    }
 }