Reorganized the Recording package target into folders.

Packages/Features/Sources/Recording/Protocols/RecordingService.swift

@@ -21,33 +21,3 @@ public protocol RecordingService: Sendable {
     func stop() async throws -> Data
 
 }
-
-// MARK: - Services
-
-/// The recording service used by default, which simulates the audio capture without touching a microphone.
-public struct SimulatedRecordingService: RecordingService {
-
-    // MARK: Initializers
-
-    /// Creates a simulated recording service.
-    public init() {}
-
-    // MARK: Methods
-
-    /// Simulates the start of an audio recording.
-    public func start() async throws {}
-
-    /// Simulates the pause of an ongoing recording.
-    public func pause() async throws {}
-
-    /// Simulates the resumption of a paused recording.
-    public func resume() async throws {}
-
-    /// Simulates the stop of a recording.
-    ///
-    /// - Returns: An empty audio payload.
-    public func stop() async throws -> Data {
-        .init()
-    }
-
-}

Packages/Features/Sources/Recording/Protocols/TranscribingService.swift

@@ -0,0 +1,15 @@
+import Foundation
+
+/// A service that transcribes recorded audio into text for the Recording feature.
+///
+/// ``RecordingView`` attaches the service to its model at initialization, so the transcription can be swapped without touching the feature's
+/// state machine — for example, with a real transcription backend in the app, or with a fast mock in unit tests.
+public protocol TranscribingService: Sendable {
+
+    /// Transcribes the given recorded audio into text.
+    ///
+    /// - Parameter audio: The recorded audio to transcribe.
+    /// - Returns: The transcription of the recorded audio.
+    func transcribe(_ audio: Data) async throws -> String
+
+}

Packages/Features/Sources/Recording/Services/AudioRecordingService.swift

@@ -0,0 +1,136 @@
+import AVFoundation
+
+/// The recording service that captures real audio from the device's microphone.
+///
+/// The service records into a temporary `.m4a` file through an `AVAudioRecorder`, and returns the file's contents when the recording stops.
+/// The user's permission to record is requested before a recording starts and, on the platforms that require it, the shared audio session is
+/// configured for recording while the capture is in progress.
+@MainActor
+public final class AudioRecordingService: RecordingService {
+
+    // MARK: Properties
+
+    /// The recorder that captures the audio from the microphone into a temporary file.
+    private var recorder: AVAudioRecorder?
+
+    // MARK: Initializers
+
+    /// Creates an audio recording service.
+    public init() {}
+
+    // MARK: Methods
+
+    /// Starts a new audio recording from the microphone.
+    ///
+    /// - Throws: ``AudioRecordingError/permissionNotGranted`` when the user denies the app access to the microphone,
+    /// ``AudioRecordingError/captureNotStarted`` when the recorder fails to start, or any error thrown while configuring
+    /// the audio session or creating the recorder.
+    public func start() async throws {
+        guard await AVAudioApplication.requestRecordPermission() else {
+            throw AudioRecordingError.permissionNotGranted
+        }
+
+        #if os(iOS) || os(visionOS)
+        let session = AVAudioSession.sharedInstance()
+
+        try session.setCategory(.record, mode: .default)
+        try session.setActive(true)
+        #endif
+
+        let recorder = try AVAudioRecorder(
+            url: Constant.File.url,
+            settings: Constant.Audio.settings
+        )
+
+        guard recorder.record() else {
+            throw AudioRecordingError.captureNotStarted
+        }
+
+        self.recorder = recorder
+    }
+
+    /// Pauses the ongoing recording.
+    ///
+    /// - Throws: ``AudioRecordingError/noOngoingRecording`` when no recording is in progress.
+    public func pause() async throws {
+        guard let recorder else {
+            throw AudioRecordingError.noOngoingRecording
+        }
+
+        recorder.pause()
+    }
+
+    /// Resumes a paused recording.
+    ///
+    /// - Throws: ``AudioRecordingError/noOngoingRecording`` when no recording is in progress, or
+    /// ``AudioRecordingError/captureNotStarted`` when the recorder fails to resume.
+    public func resume() async throws {
+        guard let recorder else {
+            throw AudioRecordingError.noOngoingRecording
+        }
+        guard recorder.record() else {
+            throw AudioRecordingError.captureNotStarted
+        }
+    }
+
+    /// Stops the recording, deleting the temporary audio file after its contents are read.
+    ///
+    /// - Returns: The audio captured since the recording started.
+    /// - Throws: ``AudioRecordingError/noOngoingRecording`` when no recording is in progress, or any error thrown
+    /// while reading the recorded audio file.
+    public func stop() async throws -> Data {
+        guard let recorder else {
+            throw AudioRecordingError.noOngoingRecording
+        }
+
+        recorder.stop()
+
+        self.recorder = nil
+
+        #if os(iOS) || os(visionOS)
+        try? AVAudioSession.sharedInstance().setActive(false)
+        #endif
+
+        defer {
+            try? FileManager.default.removeItem(at: Constant.File.url)
+        }
+
+        return try Data(contentsOf: Constant.File.url)
+    }
+
+}
+
+// MARK: - Errors
+
+/// The errors thrown by ``AudioRecordingService``.
+public enum AudioRecordingError: Error {
+    /// The recorder failed to start or resume the audio capture.
+    case captureNotStarted
+    /// No recording is in progress.
+    case noOngoingRecording
+    /// The user denied the app permission to record audio from the microphone.
+    case permissionNotGranted
+}
+
+// MARK: - Constants
+
+/// The constant values used across the audio recording service.
+private enum Constant {
+    /// The audio constants.
+    enum Audio {
+        /// The settings of the recorded audio: single-channel AAC at a 44.1 kHz sample rate, encoded in high quality.
+        @MainActor
+        static let settings: [String: Any] = [
+            AVFormatIDKey: kAudioFormatMPEG4AAC,
+            AVNumberOfChannelsKey: 1,
+            AVSampleRateKey: 44_100.0,
+            AVEncoderAudioQualityKey: AVAudioQuality.high.rawValue,
+        ]
+    }
+
+    /// The file constants.
+    enum File {
+        /// The location of the temporary file the audio is captured into.
+        static let url = FileManager.default.temporaryDirectory.appending(path: "recording.m4a")
+    }
+}

Packages/Features/Sources/Recording/Services/AudioTranscribingService.swift

@@ -0,0 +1,80 @@
+import AVFoundation
+import Speech
+
+/// The transcribing service that transcribes recorded audio into text on device.
+///
+/// The service writes the recorded audio into a temporary `.m4a` file and runs it through a `SpeechAnalyzer` with a `SpeechTranscriber`
+/// module, joining the finalized results into the returned text. The speech model assets for the current locale are downloaded and installed
+/// on first use; every transcription after that happens entirely offline.
+public struct AudioTranscribingService: TranscribingService {
+
+    // MARK: Initializers
+
+    /// Creates an audio transcribing service.
+    public init() {}
+
+    // MARK: Methods
+
+    /// Transcribes the given recorded audio into text, deleting the temporary audio file when the transcription finishes.
+    ///
+    /// - Parameter audio: The recorded audio to transcribe.
+    /// - Returns: The transcription of the recorded audio.
+    /// - Throws: ``AudioTranscribingError/localeNotSupported`` when the transcriber does not support the current locale, or any
+    /// error thrown while installing the speech model assets, reading the audio file, or analyzing its contents.
+    public func transcribe(_ audio: Data) async throws -> String {
+        try audio.write(to: Constant.File.url)
+
+        defer {
+            try? FileManager.default.removeItem(at: Constant.File.url)
+        }
+
+        guard let locale = await SpeechTranscriber.supportedLocale(equivalentTo: .current) else {
+            throw AudioTranscribingError.localeNotSupported
+        }
+
+        let transcriber = SpeechTranscriber(
+            locale: locale,
+            preset: .transcription
+        )
+
+        if let request = try await AssetInventory.assetInstallationRequest(supporting: [transcriber]) {
+            try await request.downloadAndInstall()
+        }
+
+        let analyzer = SpeechAnalyzer(modules: [transcriber])
+
+        async let text = transcriber.results.reduce(into: "") { text, result in
+            text += String(result.text.characters)
+        }
+
+        let file = try AVAudioFile(forReading: Constant.File.url)
+
+        if let lastSampleTime = try await analyzer.analyzeSequence(from: file) {
+            try await analyzer.finalizeAndFinish(through: lastSampleTime)
+        } else {
+            await analyzer.cancelAndFinishNow()
+        }
+
+        return try await text
+    }
+
+}
+
+// MARK: - Errors
+
+/// The errors thrown by ``AudioTranscribingService``.
+public enum AudioTranscribingError: Error {
+    /// The transcriber does not support the current locale.
+    case localeNotSupported
+}
+
+// MARK: - Constants
+
+/// The constant values used across the audio transcribing service.
+private enum Constant {
+    /// The file constants.
+    enum File {
+        /// The location of the temporary file the recorded audio is written into for the analysis.
+        static let url = FileManager.default.temporaryDirectory.appending(path: "transcription.m4a")
+    }
+}

Packages/Features/Sources/Recording/Services/DummyRecordingService.swift

@@ -0,0 +1,27 @@
+import Foundation
+
+/// The recording service used for development, which simulates the audio capture without touching a microphone.
+///
+/// The service is internal on purpose: it only backs the feature's previews and the default values of its model, and is not part of the
+/// package's public interface.
+struct DummyRecordingService: RecordingService {
+
+    // MARK: Methods
+
+    /// Simulates the start of an audio recording.
+    func start() async throws {}
+
+    /// Simulates the pause of an ongoing recording.
+    func pause() async throws {}
+
+    /// Simulates the resumption of a paused recording.
+    func resume() async throws {}
+
+    /// Simulates the stop of a recording.
+    ///
+    /// - Returns: An empty audio payload.
+    func stop() async throws -> Data {
+        .init()
+    }
+
+}

Packages/Features/Sources/Recording/Services/DummyTranscribingService.swift

@@ -0,0 +1,38 @@
+import Foundation
+
+/// The transcribing service used for development, which simulates the transcription work.
+///
+/// The service is internal on purpose: it only backs the feature's previews and the default values of its model, and is not part of the
+/// package's public interface.
+struct DummyTranscribingService: TranscribingService {
+
+    // MARK: Methods
+
+    /// Simulates the transcription of the given recorded audio with a two-second delay.
+    ///
+    /// - Parameter audio: The recorded audio to transcribe.
+    /// - Returns: A dummy transcription.
+    func transcribe(_ audio: Data) async throws -> String {
+        try await Task.sleep(for: Constant.Delay.transcribing)
+
+        return Constant.Text.transcription
+    }
+
+}
+
+// MARK: - Constants
+
+/// The constant values used across the transcribing services.
+private enum Constant {
+    /// The delay constants.
+    enum Delay {
+        /// The duration of the simulated transcription work.
+        static let transcribing: Duration = .seconds(2)
+    }
+
+    /// The text constants.
+    enum Text {
+        /// The dummy transcription of a recorded audio.
+        static let transcription = "This is a dummy transcription of the recorded audio."
+    }
+}

Packages/Features/Sources/Recording/TranscribingService.swift

@@ -1,56 +0,0 @@
-import Foundation
-
-/// A service that transcribes recorded audio into text for the Recording feature.
-///
-/// ``RecordingView`` attaches the service to its model at initialization, so the transcription can be swapped without touching the feature's
-/// state machine — for example, with a real transcription backend in the app, or with a fast mock in unit tests.
-public protocol TranscribingService: Sendable {
-
-    /// Transcribes the given recorded audio into text.
-    ///
-    /// - Parameter audio: The recorded audio to transcribe.
-    /// - Returns: The transcription of the recorded audio.
-    func transcribe(_ audio: Data) async throws -> String
-
-}
-
-// MARK: - Services
-
-/// The transcribing service used by default, which simulates the transcription work.
-public struct SimulatedTranscribingService: TranscribingService {
-
-    // MARK: Initializers
-
-    /// Creates a simulated transcribing service.
-    public init() {}
-
-    // MARK: Methods
-
-    /// Simulates the transcription of the given recorded audio with a two-second delay.
-    ///
-    /// - Parameter audio: The recorded audio to transcribe.
-    /// - Returns: A dummy transcription.
-    public func transcribe(_ audio: Data) async throws -> String {
-        try await Task.sleep(for: Constant.Delay.transcribing)
-
-        return Constant.Text.transcription
-    }
-
-}
-
-// MARK: - Constants
-
-/// The constant values used across the transcribing services.
-private enum Constant {
-    /// The delay constants.
-    enum Delay {
-        /// The duration of the simulated transcription work.
-        static let transcribing: Duration = .seconds(2)
-    }
-
-    /// The text constants.
-    enum Text {
-        /// The dummy transcription of a recorded audio.
-        static let transcription = "This is a dummy transcription of the recorded audio."
-    }
-}

Packages/Features/Sources/Recording/View Models/RecordingViewModel.swift

@@ -40,11 +40,11 @@ extension RecordingView {
         /// Creates a model attached to the given recording and transcribing services.
         ///
         /// - Parameters:
-        ///   - recorder: The service that captures the audio from a microphone. Defaults to ``SimulatedRecordingService``.
-        ///   - transcriber: The service that transcribes the recorded audio into text. Defaults to ``SimulatedTranscribingService``.
+        ///   - recorder: The service that captures the audio from a microphone. Defaults to ``DummyRecordingService``.
+        ///   - transcriber: The service that transcribes the recorded audio into text. Defaults to ``DummyTranscribingService``.
         init(
-            recorder: any RecordingService = SimulatedRecordingService(),
-            transcriber: any TranscribingService = SimulatedTranscribingService()
+            recorder: any RecordingService = DummyRecordingService(),
+            transcriber: any TranscribingService = DummyTranscribingService()
         ) {
             self.recorder = recorder
             self.transcriber = transcriber

Packages/Features/Sources/Recording/Views/RecordingView.swift

@@ -123,7 +123,7 @@ private enum Constant {
     "Recording view"
 ) {
     RecordingView(
-        recorder: SimulatedRecordingService(),
-        transcriber: SimulatedTranscribingService()
+        recorder: DummyRecordingService(),
+        transcriber: DummyTranscribingService()
     )
 }