Add initial VAD support

VoiceInk/Whisper/LibWhisper.swift

@@ -32,7 +32,7 @@ actor WhisperContext {
         }
     }
 
-    func fullTranscribe(samples: [Float]) {
+    func fullTranscribe(samples: [Float]) async {
         guard let context = context else { return }
         
         // Leave 2 processors free (i.e. the high-efficiency cores).
@@ -76,15 +76,26 @@ actor WhisperContext {
 
         whisper_reset_timings(context)
         logger.notice("⚙️ Starting whisper transcription")
-        samples.withUnsafeBufferPointer { samples in
-            if (whisper_full(context, params, samples.baseAddress, Int32(samples.count)) != 0) {
-                logger.error("❌ Failed to run whisper model")
-            } else {
-                // Print detected language info before timings
-                let langId = whisper_full_lang_id(context)
-                let detectedLang = String(cString: whisper_lang_str(langId))
-                logger.notice("✅ Transcription completed - Language: \(detectedLang)")
-                
+        
+        if let vadModelPath = await VADModelManager.shared.getModelPath() {
+            logger.notice("Successfully retrieved VAD model path.")
+            params.vad = true
+            params.vad_model_path = (vadModelPath as NSString).utf8String
+            
+            var vadParams = whisper_vad_default_params()
+            vadParams.min_speech_duration_ms = 500
+            vadParams.min_silence_duration_ms = 500
+            vadParams.samples_overlap = 0.1
+            params.vad_params = vadParams
+            
+            logger.notice("🎤 VAD configured: min_speech=500ms, min_silence=500ms, overlap=100ms")
+        } else {
+            logger.error("VAD model path not found, proceeding without VAD.")
+        }
+        
+        samples.withUnsafeBufferPointer { samplesBuffer in
+            if whisper_full(context, params, samplesBuffer.baseAddress, Int32(samplesBuffer.count)) != 0 {
+                self.logger.error("Failed to run whisper_full")
             }
         }
         
@@ -140,7 +151,7 @@ actor WhisperContext {
 
     func setPrompt(_ prompt: String?) {
         self.prompt = prompt
-        logger.debug("💬 Prompt set: \(prompt ?? "none")")
+        logger.notice("💬 Prompt set: \(prompt ?? "none")")
     }
 }
 

VoiceInk/Whisper/VADModelManager.swift

@@ -0,0 +1,81 @@
+import Foundation
+import OSLog
+
+class VADModelManager {
+    static let shared = VADModelManager()
+    private let logger = Logger(subsystem: "VADModelManager", category: "ModelManagement")
+    
+    private let modelURL = URL(string: "https://huggingface.co/ggml-org/whisper-vad/resolve/main/ggml-silero-v5.1.2.bin")!
+    private var modelPath: URL? {
+        guard let appSupportDir = FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first else {
+            return nil
+        }
+        // Using the same directory structure as WhisperState for consistency
+        let modelsDir = appSupportDir.appendingPathComponent("com.prakashjoshipax.VoiceInk/WhisperModels")
+        return modelsDir.appendingPathComponent("ggml-silero-v5.1.2.bin")
+    }
+
+    private init() {
+        if let modelPath = modelPath {
+            let directory = modelPath.deletingLastPathComponent()
+            if !FileManager.default.fileExists(atPath: directory.path) {
+                do {
+                    try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true, attributes: nil)
+                    logger.log("Created directory for VAD model at \(directory.path)")
+                } catch {
+                    logger.error("Failed to create model directory: \(error.localizedDescription)")
+                }
+            }
+        }
+    }
+
+    func getModelPath() async -> String? {
+        guard let modelPath = modelPath else {
+            logger.error("Could not construct VAD model path.")
+            return nil
+        }
+
+        if FileManager.default.fileExists(atPath: modelPath.path) {
+            logger.log("VAD model already exists at \(modelPath.path)")
+            return modelPath.path
+        } else {
+            logger.log("VAD model not found, downloading...")
+            return await downloadModel(to: modelPath)
+        }
+    }
+
+    private func downloadModel(to path: URL) async -> String? {
+        return await withCheckedContinuation { continuation in
+            let task = URLSession.shared.downloadTask(with: modelURL) { location, response, error in
+                DispatchQueue.main.async {
+                    if let error = error {
+                        self.logger.error("Failed to download VAD model: \(error.localizedDescription)")
+                        continuation.resume(returning: nil)
+                        return
+                    }
+
+                    guard let location = location else {
+                        self.logger.error("Download location is nil.")
+                        continuation.resume(returning: nil)
+                        return
+                    }
+
+                    do {
+                        // Ensure the destination directory exists
+                        let directory = path.deletingLastPathComponent()
+                        if !FileManager.default.fileExists(atPath: directory.path) {
+                             try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true, attributes: nil)
+                        }
+                        try FileManager.default.moveItem(at: location, to: path)
+                        self.logger.log("Successfully downloaded and moved VAD model to \(path.path)")
+                        continuation.resume(returning: path.path)
+                    } catch {
+                        self.logger.error("Failed to move VAD model to destination: \(error.localizedDescription)")
+                        continuation.resume(returning: nil)
+                    }
+                }
+            }
+            task.resume()
+        }
+    }
+}