Restructured the Sample app target in the Xcode project and added its unit tests target as well.

2026-07-05 15:45:09 +02:00
parent 21d86cdc33
commit 8576d6bac6
7 changed files with 665 additions and 51 deletions
@@ -0,0 +1,236 @@
+import Foundation
+import Notifying
+import Observation
+import Recording
+
+extension ContentView {
+
+    /// The observable model that drives ``ContentView``.
+    ///
+    /// The model owns the recording and transcribing services attached to the recording feature, along with the ``locale`` the feature
+    /// transcribes in, picked in the view's toolbar from the supported ``locales`` that ``load()`` fetches. It also holds the transcription
+    /// currently presented in the view's modal sheet: ``received(_:)`` presents the transcription of a processed recording, and
+    /// ``dismissed()`` clears it when the sheet closes.
+    ///
+    /// Every picked locale kicks off ``preinstall()``, a cancellable task that preinstalls the locale's speech model assets through the
+    /// preinstalling service — cancelling any download still in flight for a previously picked locale. The service's started, cancelled, and
+    /// failed download events are mapped to the transient, self-dismissing notifications of the ``notifier``.
+    @MainActor
+    @Observable
+    final class Model {
+
+        // MARK: Properties
+
+        /// The locale of the spoken language to transcribe.
+        var locale: Locale
+
+        /// The transcription currently presented in the modal sheet, or `nil` when none is shown.
+        var transcription: Transcription?
+
+        /// The locales the transcriber supports, sorted by their localized names, or empty while ``load()`` has not finished yet.
+        private(set) var locales: [Locale]
+
+        /// The service that captures the audio from a microphone.
+        @ObservationIgnored
+        let capturer: any Capturing
+
+        /// The locale whose speech model assets are preinstalled or being preinstalled, or `nil` when none are.
+        @ObservationIgnored
+        private var localePreinstalling: Locale?
+
+        /// The notifier that owns the transient in-app notifications reporting the download events.
+        @ObservationIgnored
+        let notifier: Notifier
+
+        /// The service that preinstalls the speech model assets of a picked locale.
+        @ObservationIgnored
+        private let preinstaller: any Preinstalling
+
+        /// The task that listens to the events emitted by the preinstalling service, or `nil` until the first preinstallation starts.
+        @ObservationIgnored
+        private var taskEvents: Task<Void, Never>?
+
+        /// The task that preinstalls the speech model assets of the last picked locale, or `nil` until the first locale is picked.
+        @ObservationIgnored
+        private var taskPreinstall: Task<Void, Never>?
+
+        /// The service that transcribes the recorded audio into text.
+        @ObservationIgnored
+        let transcriber: any Transcribing
+
+        // MARK: Initializers
+
+        /// Creates a model set to the user's current locale, with no supported locales loaded yet, attached to the given services
+        /// and notifier.
+        ///
+        /// - Parameters:
+        ///   - capturer: The service that captures the audio from a microphone. Defaults to the on-device ``AudioCapturing``.
+        ///   - preinstaller: The service that preinstalls the speech model assets of a picked locale. Defaults to ``AssetPreinstalling``.
+        ///   - transcriber: The service that transcribes the recorded audio into text. Defaults to the on-device ``AudioTranscribing``.
+        ///   - notifier: The notifier that owns the transient in-app notifications. Defaults to a notifier with its standard dismissal delay.
+        init(
+            capturer: any Capturing = AudioCapturing(),
+            preinstaller: any Preinstalling = AssetPreinstalling(),
+            transcriber: any Transcribing = AudioTranscribing(),
+            notifier: Notifier = .init(),
+        ) {
+            self.locale = .current
+            self.locales = []
+            self.capturer = capturer
+            self.notifier = notifier
+            self.preinstaller = preinstaller
+            self.transcriber = transcriber
+        }
+
+        // MARK: Methods
+
+        /// Loads the locales the transcriber supports into ``locales``, sorted by their localized names, and aligns ``locale`` with the
+        /// supported equivalent of its current value — falling back to the supported equivalent of a default locale when none exists —
+        /// so the locale picker starts with a valid selection.
+        func load() async {
+            locales =
+                await preinstaller
+                .supportedLocales()
+                .sorted {
+                    name(for: $0).localizedStandardCompare(name(for: $1)) == .orderedAscending
+                }
+
+            locale =
+                if let equivalent = await preinstaller.supportedLocale(equivalentTo: locale) {
+                    equivalent
+                }
+                else if let fallback = await preinstaller.supportedLocale(equivalentTo: .byDefault) {
+                    fallback
+                }
+                else {
+                    .current
+                }
+
+            preinstall()
+        }
+
+        /// Preinstalls the speech model assets for the current ``locale`` in a cancellable task, cancelling the preinstallation of any
+        /// previously picked locale still in flight — which the ``notifier`` reports as a cancelled download. Does nothing when the
+        /// current locale is the one already preinstalled or being preinstalled.
+        func preinstall() {
+            guard localePreinstalling != locale else {
+                return
+            }
+
+            taskPreinstall?.cancel()
+
+            localePreinstalling = locale
+
+            listenToEvents()
+
+            taskPreinstall = Task { [locale] in
+                await preinstaller.preinstall(for: locale)
+            }
+        }
+
+        /// Returns the localized name of a locale for the locale picker.
+        ///
+        /// - Parameter locale: The locale to name.
+        /// - Returns: The name of the locale in the user's current locale, or its identifier when no name is available.
+        func name(
+            for locale: Locale
+        ) -> String {
+            Locale
+                .current
+                .localizedString(
+                    forIdentifier: locale.identifier
+                )?.localizedCapitalized
+                ?? locale.identifier
+        }
+
+        /// Handles the transcription of a processed recording, presenting it in the modal sheet.
+        ///
+        /// - Parameter transcription: The transcription of the processed recording.
+        func received(
+            _ transcription: Transcription
+        ) {
+            self.transcription = transcription
+        }
+
+        /// Handles the dismissal of the modal sheet.
+        func dismissed() {
+            transcription = nil
+        }
+
+    }
+
+}
+
+// MARK: - Helpers
+
+private extension ContentView.Model {
+
+    // MARK: Methods
+
+    /// Starts listening to the events emitted by the preinstalling service, unless already listening: every started, cancelled, and
+    /// failed download is posted to the ``ContentView/Model/notifier``, and a cancellation or failure clears the preinstalled locale
+    /// — only when it is still the affected one, so a newer preinstallation is never forgotten — letting a re-pick retry.
+    func listenToEvents() {
+        guard taskEvents == nil else {
+            return
+        }
+
+        taskEvents = Task { [weak self, events = preinstaller.events] in
+            for await event in events {
+                guard let self else {
+                    return
+                }
+
+                switch event {
+                case .cancelled(let locale):
+                    if localePreinstalling == locale {
+                        localePreinstalling = nil
+                    }
+
+                    notifier.post(
+                        .warning,
+                        message: String(localized: .viewRecordingNotificationDownloadCancelled(name(for: locale))),
+                        symbol: Constant.Symbol.cancelled
+                    )
+                case .failed(let locale):
+                    if localePreinstalling == locale {
+                        localePreinstalling = nil
+                    }
+
+                    notifier.post(
+                        .error,
+                        message: String(localized: .viewRecordingNotificationDownloadFailed(name(for: locale))),
+                        symbol: Constant.Symbol.failed
+                    )
+                case .started(let locale):
+                    notifier.post(
+                        .info,
+                        message: String(localized: .viewRecordingNotificationDownloadStarted(name(for: locale))),
+                        symbol: Constant.Symbol.started
+                    )
+                }
+            }
+        }
+    }
+
+}
+
+// MARK: - Constants
+
+/// The constant values used across the model.
+private enum Constant {
+    /// The symbol constants.
+    enum Symbol {
+        /// The system symbol of a cancelled download.
+        static let cancelled = "xmark.circle"
+        /// The system symbol of a failed download.
+        static let failed = "exclamationmark.triangle"
+        /// The system symbol of a started download.
+        static let started = "arrow.down.circle"
+    }
+}
+
+private extension Locale {
+    /// The locale to fall back to when the transcriber supports no equivalent of the user's current locale.
+    static let byDefault: Locale = .init(identifier: "en_US")
+}