Enable pruning downloaded models

Sources/LocalLLMClientCore/LLMSession.swift

@@ -302,6 +302,21 @@ public extension LLMSession {
         public func downloadModel(onProgress: @Sendable @escaping (Double) async -> Void = { _ in }) async throws {
             try await downloader.download(onProgress: onProgress)
         }
+
+        public static func removeAllModels(
+            in url: URL = FileDownloader.defaultRootDestination,
+            excludingModels: [any Model] = []
+        ) throws {
+            let excludedURLs: [URL] = excludingModels.compactMap { model -> URL? in
+                switch model {
+                case let model as LLMSession.DownloadModel: model.modelPath
+                case let model as LLMSession.LocalModel: model.modelPath
+                default: nil
+                }
+            }
+
+            try FileManager.default.removeAllItems(in: url, excludingURLs: excludedURLs)
+        }
     }
 
     struct LocalModel: Model {

Sources/LocalLLMClientUtility/FileManager+.swift

@@ -0,0 +1,36 @@
+import Foundation
+
+package extension FileManager {
+    func removeEmptyDirectories(in url: URL) throws {
+        guard url.isFileURL else { return }
+
+        let contents = try contentsOfDirectory(at: url, includingPropertiesForKeys: [.isDirectoryKey])
+        let subdirectories = try contents.filter { try $0.resourceValues(forKeys: [.isDirectoryKey]).isDirectory ?? false }
+
+        for subdirectory in subdirectories { try removeEmptyDirectories(in: subdirectory) }
+
+        guard try contentsOfDirectory(at: url, includingPropertiesForKeys: nil).isEmpty else { return }
+
+        try removeItem(at: url)
+    }
+
+    func removeAllItems(in url: URL, excludingURLs: [URL] = [], removingEmptyDirectories: Bool = true) throws {
+        guard let enumerator = enumerator(at: url, includingPropertiesForKeys: [.isDirectoryKey], options: [.skipsPackageDescendants]) else { return }
+
+        let excludingURLsNormalized: Set<URL> = Set(excludingURLs.map { $0.resolvingSymlinksInPath().standardizedFileURL
+        })
+
+        for case let fileURL as URL in enumerator {
+            if excludingURLsNormalized.contains(fileURL.resolvingSymlinksInPath().standardizedFileURL) {
+                enumerator.skipDescendants()
+                continue
+            }
+
+            if (try fileURL.resourceValues(forKeys: [.isDirectoryKey])).isDirectory == false {
+                try removeItem(at: fileURL)
+            }
+        }
+
+        if removingEmptyDirectories { try removeEmptyDirectories(in: url) }
+    }
+}