SyncViewModel.kt

1package com.peachpasswords.ui.sync23import android.content.Context4import androidx.lifecycle.ViewModel5import androidx.lifecycle.viewModelScope6import com.peachpasswords.sync.BackgroundSyncCoordinator7import com.peachpasswords.sync.BackgroundSyncPreference8import com.peachpasswords.sync.SyncVaultAdapter9import com.peachpasswords.sync.PairedDevice10import com.peachpasswords.sync.PairedDeviceStore11import com.peachpasswords.sync.PendingVouchedDevice12import com.peachpasswords.sync.PendingVouchedDeviceStore13import com.peachpasswords.sync.hexToPubkey14import com.peachpasswords.sync.PeachSyncService15import com.peachpasswords.sync.RelayDecision16import com.peachpasswords.sync.RelaySettingsStore17import com.peachpasswords.sync.SyncMode18import com.peachpasswords.sync.SyncAlertStore19import com.peachpasswords.sync.SyncOutcomeReason20import com.peachpasswords.sync.SyncOutcomeStore21import com.peachpasswords.sync.SyncOutcomeSummary22import com.peachpasswords.sync.VaultSyncAdapter23import com.peachpasswords.sync.buildLocalIdentity24import com.peachpasswords.sync.deriveLocalSyncKeypair25import com.peachpasswords.sync.getOrCreateDeviceId26import com.peachpasswords.vault.VaultCrypto27import com.peachpasswords.vault.VaultRepository28import dagger.hilt.android.lifecycle.HiltViewModel29import dagger.hilt.android.qualifiers.ApplicationContext30import kotlinx.coroutines.flow.MutableStateFlow31import kotlinx.coroutines.flow.SharingStarted32import kotlinx.coroutines.flow.StateFlow33import kotlinx.coroutines.flow.asStateFlow34import kotlinx.coroutines.flow.stateIn35import kotlinx.coroutines.delay36import kotlinx.coroutines.Job37import kotlinx.coroutines.launch38import javax.inject.Inject3940/**41 * Backs the Sync settings card: relay mode, the paired-device list, and the42 * manual sync control.43 *44 * Sync itself runs in [PeachSyncService], which holds a socket in each paired45 * peer's rendezvous room. Which side opens the conversation there depends on46 * the peer: we wait for a browser extension, because an extension can only47 * dial, and for another phone the lower long-term key dials. So48 * "sync now" makes sure the service is up and asks it to re-read the device49 * list — the work happens there, not here. See docs/sync-lan-retirement.md.50 */51@HiltViewModel52class SyncViewModel @Inject constructor(53    @ApplicationContext private val context: Context,54    private val vault: VaultRepository,55    private val deviceStore: PairedDeviceStore,56    private val pendingVouchedStore: PendingVouchedDeviceStore,57    private val syncAlertStore: SyncAlertStore,58    private val backgroundSync: BackgroundSyncPreference,59    private val relaySettings: RelaySettingsStore,60    private val syncOutcomes: SyncOutcomeStore,61) : ViewModel() {6263    /** The last sync attempt, whatever it was. Survives process death. */64    val status: StateFlow<SyncOutcomeSummary> = syncOutcomes.summary6566    val backgroundSyncEnabled: StateFlow<Boolean> = backgroundSync.enabled6768    /**69     * Decides when the sync service actually runs for the background-sync70     * preference. The service's own locked-handling is the gate — refusing to71     * start here while locked used to leave the preference on with no72     * notification, which was exactly the v2.5.13 "no peer answered" symptom.73     */74    private val backgroundSyncCoordinator = BackgroundSyncCoordinator(75        start = { PeachSyncService.start(context) },76        stop = { PeachSyncService.stop(context) },77        isUnlocked = vault.isUnlocked,78        preferenceEnabled = backgroundSync.enabled,79    )8081    init {82        // Catches the lock-then-unlock case: the user enables the setting while83        // locked, then unlocks — the service should come up the moment a sync84        // identity exists. StateFlow.collect fires the current value85        // immediately, so the already-unlocked case is covered too.86        backgroundSyncCoordinator.observe(viewModelScope)87    }8889    fun setBackgroundSyncEnabled(enabled: Boolean) {90        backgroundSync.setEnabled(enabled)91        backgroundSyncCoordinator.setEnabled(enabled)92    }9394    /** Blank while no private relay is configured, so the field stays honest. */95    private val _privateRelayUrl = MutableStateFlow(relaySettings.privateRelayUrl())96    val privateRelayUrl: StateFlow<String> = _privateRelayUrl.asStateFlow()979899    private val _syncMode = MutableStateFlow(relaySettings.syncMode())100    val syncMode: StateFlow<SyncMode> = _syncMode.asStateFlow()101102    fun setSyncMode(mode: SyncMode) {103        relaySettings.setSyncMode(mode)104        _syncMode.value = relaySettings.syncMode()105        _privateRelayUrl.value = relaySettings.privateRelayUrl()106    }107108    /** A custom URL implies private mode. Returns false on an invalid URL. */109    fun setRelayUrl(input: String): Boolean = runCatching {110        relaySettings.setRelayUrl(input)111        _privateRelayUrl.value = relaySettings.privateRelayUrl()112        _syncMode.value = relaySettings.syncMode()113        true114    }.getOrDefault(false)115116117    /** Live list of trusted peers, backing the Sync settings card device list (C7). */118    val pairedDevices: StateFlow<List<PairedDevice>> =119        deviceStore.observeAll()120            .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000), emptyList())121122    val pendingVouched: StateFlow<List<PendingVouchedDevice>> =123        pendingVouchedStore.observeAll()124            .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5_000), emptyList())125126    /**127     * Revoke a paired device. Removing it REVOKES rather than just dropping the128     * local row: a plain removal is undone the moment any other peer vouches it129     * back through a manifest, which is exactly what the relay makes easy.130     */131    fun unpairDevice(id: String) = viewModelScope.launch {132        deviceStore.revoke(id, getOrCreateDeviceId(context))133        // Revocation is mesh state, not a vault-entry mutation. Wake the relay134        // service immediately so the signed revocation reaches every remaining135        // peer instead of waiting for a later foreground or periodic trigger.136        PeachSyncService.start(context)137    }138139    fun confirmVouchedDevice(id: String) = viewModelScope.launch {140        val pending = pendingVouchedStore.get(id) ?: return@launch141        // Last gate before a vouched device becomes a sync peer. A queue entry142        // can predate the revocation that names it, so revocation is re-checked143        // here rather than trusted to have swept the queue.144        if (deviceStore.isRevoked(pending.deviceId, pending.longTermPublicKeyHex)) {145            pendingVouchedStore.remove(id)146            return@launch147        }148        deviceStore.upsert(149            PairedDevice(150                deviceId = pending.deviceId,151                deviceName = pending.deviceName,152                deviceType = pending.deviceType,153                longTermPublicKeyHex = pending.longTermPublicKeyHex,154                signingPublicKeyHex = pending.signingPublicKeyHex,155                trustSource = "vouched",156                wsPort = pending.wsPort,157                pairedAt = pending.pairedAt,158            ),159        )160        pendingVouchedStore.remove(id)161    }162163    fun rejectVouchedDevice(id: String) = viewModelScope.launch {164        pendingVouchedStore.remove(id)165    }166167    /** Browser-style nuclear recovery path: re-key sync and forget every peer. */168    suspend fun rotateSyncIdentity(): Boolean {169        val ok = vault.rotateSyncIdentity()170        if (ok) {171            deviceStore.clear()172            syncOutcomes.reset()173        }174        return ok175    }176177    /** Adapter over the live vault; null while the vault is locked. */178    fun buildAdapter(): SyncVaultAdapter? {179        if (!vault.isUnlocked.value) return null180        return VaultSyncAdapter(181            repo = vault,182            ourDeviceId = getOrCreateDeviceId(context),183            pairedDevices = deviceStore,184            pendingVouched = pendingVouchedStore,185            syncAlerts = syncAlertStore,186        )187    }188189    /**190     * Manual trigger, and the one place a sync attempt is started on purpose.191     *192     * It used to claim a completed sync the instant the service was193     * asked to start, which is a success it had not earned — the service only194     * re-reads the device list, and the sync itself happens later in a195     * rendezvous room or not at all. Now the attempt goes busy and the outcome196     * comes from whoever actually finishes it.197     */198    fun syncNow() {199        val decision = relaySettings.relayInForce()200        if (decision is RelayDecision.Refuse) {201            syncOutcomes.report(SyncOutcomeSummary(reason = decision.reason))202            return203        }204        if (!vault.isUnlocked.value) {205            syncOutcomes.report(SyncOutcomeSummary(reason = SyncOutcomeReason.VAULT_LOCKED))206            return207        }208        // Read the store, not `pairedDevices.value`: that flow only holds a real209        // list while something is collecting it, so pull-to-refresh on the vault210        // list — which collects `status` and nothing else — always saw an empty211        // list and reported "no devices paired" against a fully paired phone.212        val devices = deviceStore.getAll()213        if (devices.isEmpty()) {214            syncOutcomes.report(SyncOutcomeSummary(reason = SyncOutcomeReason.NO_PAIRED_DEVICES))215            return216        }217        // The same filter CloudRelayReconnectListener applies when it decides218        // which rooms to hold — a peer with no rendezvous secret is skipped219        // there in silence, which is precisely the case that must not look like220        // a successful no-op.221        if (devices.none { it.rendezvousSecretHex != null }) {222            syncOutcomes.report(223                SyncOutcomeSummary(224                    reason = SyncOutcomeReason.NO_ELIGIBLE_HOST,225                    detail = devices.joinToString("; ") {226                        "${it.deviceName ?: it.deviceId} [type=${it.deviceType ?: "unset"}, trust=${it.trustSource ?: "unset"}]"227                    },228                ),229            )230            return231        }232233        syncOutcomes.begin()234        PeachSyncService.start(context)235        // Nothing else can close this attempt: the phone usually WAITS to be236        // dialled, so if no peer turns up there is no session to report a237        // failure from and the light would pulse for ever. Deliberately shorter238        // than the dialler's own bound: this one answers the person holding the239        // phone, and a session still running will report over it.240        attemptTimeout?.cancel()241        attemptTimeout = viewModelScope.launch {242            delay(SYNC_ATTEMPT_TIMEOUT_MS)243            if (syncOutcomes.summary.value.syncing) {244                syncOutcomes.report(245                    SyncOutcomeSummary(246                        reason = SyncOutcomeReason.RELAY_UNREACHABLE,247                        detail = "no peer answered within ${SYNC_ATTEMPT_TIMEOUT_MS / 1000}s",248                    ),249                )250            }251        }252    }253254    /**255     * Legacy manual / discovery trigger kept for existing callers; now routes256     * through [syncNow] so a populated device store actually dials peers.257     */258    fun triggerSync() = syncNow()259260    private var attemptTimeout: Job? = null261262    private companion object {263        const val SYNC_ATTEMPT_TIMEOUT_MS = 20_000L264    }265}