feat:mac os

macos/Sources/Transui/AudioRecorder.swift

@@ -0,0 +1,86 @@
+import AVFoundation
+import Foundation
+
+enum RecordingError: LocalizedError {
+  case microphoneDenied
+  case couldNotStart
+
+  var errorDescription: String? {
+    switch self {
+    case .microphoneDenied: "Microphone access is off. Enable it in System Settings."
+    case .couldNotStart: "The microphone could not start recording."
+    }
+  }
+}
+
+@MainActor
+final class AudioRecorder: NSObject, AVAudioRecorderDelegate {
+  private var recorder: AVAudioRecorder?
+  private var meterTimer: Timer?
+  private(set) var fileURL: URL?
+  var onLevel: ((Double) -> Void)?
+
+  func start() async throws {
+    guard await Self.requestPermission() else { throw RecordingError.microphoneDenied }
+    let fileURL = FileManager.default.temporaryDirectory
+      .appendingPathComponent("transui-\(UUID().uuidString).wav")
+    self.fileURL = fileURL
+    let settings: [String: Any] = [
+      AVFormatIDKey: Int(kAudioFormatLinearPCM),
+      AVSampleRateKey: 16_000,
+      AVNumberOfChannelsKey: 1,
+      AVLinearPCMBitDepthKey: 16,
+      AVLinearPCMIsFloatKey: false,
+      AVLinearPCMIsBigEndianKey: false,
+    ]
+    let recorder = try AVAudioRecorder(url: fileURL, settings: settings)
+    recorder.delegate = self
+    recorder.isMeteringEnabled = true
+    guard recorder.prepareToRecord(), recorder.record() else {
+      throw RecordingError.couldNotStart
+    }
+    self.recorder = recorder
+    meterTimer = Timer.scheduledTimer(withTimeInterval: 0.08, repeats: true) { [weak self] _ in
+      Task { @MainActor in self?.updateLevel() }
+    }
+  }
+
+  func stop() -> URL? {
+    meterTimer?.invalidate()
+    meterTimer = nil
+    recorder?.stop()
+    recorder = nil
+    onLevel?(0)
+    let url = fileURL
+    fileURL = nil
+    return url
+  }
+
+  func cancel() {
+    let url = stop()
+    if let url { try? FileManager.default.removeItem(at: url) }
+    fileURL = nil
+  }
+
+  private func updateLevel() {
+    guard let recorder else { return }
+    recorder.updateMeters()
+    let decibels = Double(recorder.averagePower(forChannel: 0))
+    let normalized = max(0, min(1, pow(10, decibels / 32)))
+    onLevel?(normalized)
+  }
+
+  private static func requestPermission() async -> Bool {
+    switch AVCaptureDevice.authorizationStatus(for: .audio) {
+    case .authorized: true
+    case .denied, .restricted: false
+    case .notDetermined:
+      await withCheckedContinuation { continuation in
+        AVCaptureDevice.requestAccess(for: .audio) { allowed in
+          continuation.resume(returning: allowed)
+        }
+      }
+    @unknown default: false
+    }
+  }
+}