Fix restore LN channel

Author: ben-kaufman

app/src/main/java/to/bitkit/ui/MainActivity.kt

@@ -100,14 +100,17 @@ class MainActivity : FragmentActivity() {
                     .map { it.walletExists }
                     .collectAsStateWithLifecycle(initialValue = walletViewModel.walletExists)
                 val isShowingMigrationLoading by walletViewModel.isShowingMigrationLoading.collectAsStateWithLifecycle()
+                val restoreState by walletViewModel.restoreState.collectAsStateWithLifecycle()
                 val hazeState = rememberHazeState(blurEnabled = true)
 
                 LaunchedEffect(
                     walletExists,
                     isRecoveryMode,
-                    notificationsGranted
+                    notificationsGranted,
+                    restoreState,
                 ) {
-                    if (walletExists && !isRecoveryMode && notificationsGranted) {
+                    val canStartService = walletExists && notificationsGranted && restoreState.isIdle()
+                    if (canStartService && !isRecoveryMode) {
                         tryStartForegroundService()
                     }
                 }

app/src/main/java/to/bitkit/viewmodels/AppViewModel.kt

@@ -46,6 +46,7 @@ import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import kotlinx.coroutines.withTimeout
+import org.lightningdevkit.ldknode.ChannelDataMigration
 import org.lightningdevkit.ldknode.Event
 import org.lightningdevkit.ldknode.PaymentId
 import org.lightningdevkit.ldknode.SpendableUtxo
@@ -351,13 +352,40 @@ class AppViewModel @Inject constructor(
     }
 
     private suspend fun completeRNRemoteBackupRestore() {
+        val channelMigration = buildChannelMigrationIfAvailable()
+
+        if (channelMigration != null) {
+            lightningRepo.stop().onFailure {
+                Logger.error("Failed to stop node during remote restore restart", it, context = TAG)
+            }
+            delay(REMOTE_RESTORE_NODE_RESTART_DELAY_MS)
+            lightningRepo.start(channelMigration = channelMigration, shouldRetry = false)
+                .onSuccess {
+                    migrationService.consumePendingChannelMigration()
+                    walletRepo.syncNodeAndWallet()
+                    walletRepo.syncBalances()
+                }
+                .onFailure { e ->
+                    Logger.error("Failed to restart node after remote restore: $e", e, context = TAG)
+                }
+        }
+
         lightningRepo.getPayments().onSuccess { activityRepo.syncLdkNodePayments(it) }
         migrationService.reapplyMetadataAfterSync()
         activityRepo.syncActivities()
+        walletRepo.syncBalances()
         migrationService.setRestoringFromRNRemoteBackup(false)
         migrationService.setShowingMigrationLoading(false)
     }
 
+    private fun buildChannelMigrationIfAvailable(): ChannelDataMigration? {
+        val migration = migrationService.peekPendingChannelMigration() ?: return null
+        return ChannelDataMigration(
+            channelManager = migration.channelManager.map { it.toUByte() },
+            channelMonitors = migration.channelMonitors.map { monitor -> monitor.map { it.toUByte() } },
+        )
+    }
+
     private suspend fun completeMigration() {
         if (isCompletingMigration) return
         isCompletingMigration = true
@@ -1986,6 +2014,7 @@ class AppViewModel @Inject constructor(
         private const val SCREEN_TRANSITION_DELAY_MS = 300L
         private const val MIGRATION_LOADING_TIMEOUT_MS = 300_000L
         private const val MIGRATION_AUTH_RESET_DELAY_MS = 500L
+        private const val REMOTE_RESTORE_NODE_RESTART_DELAY_MS = 500L
         private const val AUTH_CHECK_INITIAL_DELAY_MS = 1000L
         private const val AUTH_CHECK_SPLASH_DELAY_MS = 500L
     }

app/src/main/java/to/bitkit/viewmodels/WalletViewModel.kt

@@ -275,6 +275,9 @@ class WalletViewModel @Inject constructor(
     ) {
         lightningRepo.start(walletIndex, channelMigration = channelMigration)
             .onSuccess {
+                if (channelMigration != null) {
+                    migrationService.consumePendingChannelMigration()
+                }
                 walletRepo.setWalletExistsState()
                 walletRepo.syncBalances()
                 if (_restoreState.value.isIdle()) {