NoGooleApps/replica/telefon/architecture.md

Architecture: Telefon (Android, ohne Google)

Same conventions as the other apps. No network permission. The app owns almost no data: it reads the system call log and contacts.

Stack

Schicht	Wahl	warum
UI	Kotlin + Compose, M3 Expressive, dynamic colour	same as the others
Telefonie	RoleManager.ROLE_DIALER + own InCallService (BIND_INCALL_SERVICE, IN_CALL_SERVICE_UI)	the only official way to show the call UI and control calls
Anrufen	TelecomManager.placeCall	uses the default SIM/phone account, works for emergency numbers through the system
Daten	CallLog.Calls and ContactsContract via ContentResolver, observed with ContentObserver → Flow	no copy of personal data in our database
Eigene Daten	DataStore (quick replies, theme)	–
Audio	InCallService.setMuted / setAudioRoute, CallEndpoint on API 34+	speaker, earpiece, Bluetooth
Näherungssensor	PowerManager.PROXIMITY_SCREEN_OFF_WAKE_LOCK while the earpiece is active	screen off at the ear

Permissions

READ_CALL_LOG, WRITE_CALL_LOG (delete entries), READ_CONTACTS, CALL_PHONE, READ_PHONE_STATE, MANAGE_OWN_CALLS no, USE_FULL_SCREEN_INTENT, POST_NOTIFICATIONS, WAKE_LOCK, SEND_SMS no (quick replies hand off to the SMS app with smsto:). The dialer role grants most of these automatically once the user accepts it.

Data

No schema. Own state in DataStore only. Access: single user; the system enforces the permissions.

Interne API

Aufruf	macht	Flow
CallLogRepo.observe(filter)	query CallLog, join contact name/photo by number (PhoneLookup), group by day	F01
ContactsRepo.favorites() / search(q) / t9(digits)	starred contacts; name/number search; T9 digit match on names and numbers	F02, F03, F06
Dialer.call(number)	placeCall(tel:)	F01–F03
CallManager (in InCallService)	StateFlow of calls; answer, reject (with SMS), hold, unhold, mute, route, DTMF, disconnect	F04, F05, F07
Role.request()	role request intent	F08

Was beißt

• Wrong default dialer state: without the role, calls still work through the system dialer; the app shows a banner instead of failing.
• Lock screen: incoming UI via full-screen-intent notification; showWhenLocked + turnScreenOn on the activity.
• Ringtone: the system rings for the default dialer? No: the InCallService app must play the ringtone itself only when Call.Details say so; on modern Android the platform Ringer plays it for the default dialer. We do not play our own.
• Process death mid-call: the InCallService is bound by the system as long as calls exist; UI state is rebuilt from calls.
• Emergency numbers: always via placeCall, never blocked by our UI.
• Privacy: no network, no analytics; call log stays in the system.

Build-Reihenfolge

1. Slice: role request, InCallService, incoming + in-call screens, place a call from the keypad.
2. Must: call log with grouping and call back, favourites, search, notifications, mute/speaker/DTMF, proximity.
3. Should: filters, T9, hold, call waiting, quick reply SMS, details screen, voicemail, Bluetooth.