Skip to main content

Architecture

A single-module app following a Clean-ish layering with strict boundaries.

Layers​

Hard rules​

  1. UI never imports Retrofit, Firebase, or Hilt internals. Only ViewModels and domain models cross that boundary.
  2. Repositories return domain models (CompletedCallUi, UserProfile, …), not DTOs.
  3. Local stores are namespaced by Firebase uid. Two users on one device never collide.
  4. Raw audio is never persisted locally. Completed-call transcript + analysis JSON are cached in app-private storage (CallContentCache) to avoid re-downloading on every detail open; the cache is wiped on sign-out, account delete, and per-call delete.

Directory layout​

app/src/main/java/com/scryon/
├── MainActivity.kt              Single Activity, wraps content in AuthGate.
├── ScryonApplication.kt         Hilt application; Configuration.Provider for Hilt-Work;
│                                re-arms MediaStore observer + uploads notification channel.
│
├── data/
│   ├── auth/                    Firebase wrappers — AuthRepository, FirebaseIdTokenProvider
│   │                            (cached Bearer token), Google + Phone helpers, SignUpResult.
│   ├── local/                   SharedPreferences-backed stores + scanner DTO. Includes
│   │                            UploadQueueStore (pre-accept), DismissedCallStore, and
│   │                            CallContentCache (on-disk transcript/analysis JSON).
│   ├── remote/                  Retrofit interface, DTOs, interceptors (ApiKey +
│   │                            FirebaseAuth) and FirebaseAuthAuthenticator (401 retry),
│   │                            Moshi adapters, ScryonError hierarchy + mapper.
│   ├── repository/              ScryonRepository, ScryonUserRepository (impls).
│   └── scanner/                 CallRecordingScanner — MediaStore filter heuristics.
│
├── di/                          Hilt modules (NetworkModule, RepositoryModule, AppModule)
│                                + ScryonApiConfig (BuildConfig wrapper).
│
├── domain/
│   ├── model/                   ScryonModels.kt, UserModels.kt — UI-friendly domain types.
│   └── repository/              CallRepository, UserRepository (interfaces).
│
├── notifications/               BootCompletedReceiver, ContentObserver, periodic-scan
│                                worker, PostCallNotificationHelper, and
│                                UploadProgressNotificationHelper (foreground-service
│                                notification for CallUploadWorker).
│
├── work/                        WorkManager pipeline for durable uploads —
│                                CallUploadWorker (HiltWorker, foreground service) +
│                                CallUploadEnqueuer (single entry point + cancel).
│
├── ui/
│   ├── auth/                    LoginScreen, EmailVerificationScreen, AuthGate.
│   ├── components/              GlassCard, StatusChip, TagChip, EmptyState, StatsCard,
│   │                            ScryonBottomBar.
│   ├── navigation/              ScryonRoutes (string constants + tab enum).
│   ├── shell/                   ScryonRoot scaffold + tabs/ screens + shared components.
│   └── theme/                   Colours, typography, Material3 mapping.
│
├── util/                        RecordingPermissions.
└── viewmodel/                   All @HiltViewModel classes.

Coding conventions​

  • Compose first. No XML layouts. Theme tokens via LocalScryonColors.current.
  • ViewModels return StateFlow, not LiveData. UI uses collectAsStateWithLifecycle().
  • Repositories suspend for I/O. They throw mapped ScryonError subclasses; ViewModels translate to user-facing strings.
  • Hilt wires everything from Application down. New singletons go in a @Module under di/.
  • Naming. DTOs in data/remote/dto/. Domain models in domain/model/. Repository interfaces in domain/repository/; impls in data/repository/.
  • No raw audio on disk. Small JSON blobs live in local/ SharedPreferences stores; completed-call transcript + analysis JSON are cached under filesDir/scryon-call-cache/<uid>/ and cleared on sign-out / delete.
  • Comments explain why, not what. Avoid narrating obvious code.

Discovering local recordings​

CallRecordingScanner heuristically classifies a MediaStore.Audio row as a call recording based on its DISPLAY_NAME, RELATIVE_PATH / DATA, and MIME_TYPE. Positive tokens: call, recorder, voice memo, acr/, etc. Negative tokens: /ringtones/, /whatsapp/media/whatsapp, telegram, etc. The full lists live in data/scanner/CallRecordingScanner.kt.

The same scanner powers the background New-recording notification flow — see Notifications.

What's next​