fix: prevent force close channels of trusted peers

app/src/main/java/to/bitkit/repositories/LightningRepo.kt

@@ -881,6 +881,10 @@ class LightningRepo @Inject constructor(
         return isRunning && lightningService.canReceive()
     }
 
+    fun separateTrustedChannels(
+        channels: List<ChannelDetails>,
+    ): Pair<List<ChannelDetails>, List<ChannelDetails>> = lightningService.separateTrustedChannels(channels)
+
     suspend fun registerForNotifications(token: String? = null) = executeWhenNodeRunning("registerForNotifications") {
         return@executeWhenNodeRunning try {
             val token = token ?: firebaseMessaging.token.await()

app/src/main/java/to/bitkit/services/LightningService.kt

@@ -375,6 +375,19 @@ class LightningService @Inject constructor(
         return ourPeers.any { p -> p !in lspPeers }
     }
 
+    fun getLspPeerNodeIds(): Set<String> = trustedPeers.map { it.nodeId }.toSet()
+
+    fun separateTrustedChannels(
+        channels: List<ChannelDetails>,
+    ): Pair<List<ChannelDetails>, List<ChannelDetails>> {
+        val trustedPeerIds = getLspPeerNodeIds()
+        val trusted = channels.filter { it.counterpartyNodeId in trustedPeerIds }
+        val nonTrusted = channels.filter { it.counterpartyNodeId !in trustedPeerIds }
+        return trusted to nonTrusted
+    }
+
+    fun isTrustedPeer(nodeId: String): Boolean = nodeId in getLspPeerNodeIds()
+
     // endregion
 
     // region channels
@@ -418,6 +431,7 @@ class LightningService @Inject constructor(
         }
     }
 
+    @Suppress("ThrowsCount")
     suspend fun closeChannel(
         channel: ChannelDetails,
         force: Boolean = false,
@@ -427,6 +441,12 @@ class LightningService @Inject constructor(
         val channelId = channel.channelId
         val userChannelId = channel.userChannelId
         val counterpartyNodeId = channel.counterpartyNodeId
+
+        // Prevent force closing channels with trusted peers (LSP nodes)
+        if (force && isTrustedPeer(counterpartyNodeId)) {
+            throw TrustedPeerForceCloseException()
+        }
+
         try {
             ServiceQueue.LDK.background {
                 Logger.debug("Initiating channel close (force=$force): '$channelId'", context = TAG)
@@ -952,6 +972,10 @@ data class NetworkGraphInfo(
     val latestRgsSyncTimestamp: ULong?,
 )
 
+class TrustedPeerForceCloseException : Exception(
+    "Cannot force close channel with trusted peer. Force close is disabled for Blocktank LSP channels."
+)
+
 // region helpers
 /**
  * TODO remove, replace all usages with [FeeRate.fromSatPerVbUnchecked]

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

@@ -592,6 +592,7 @@ private fun RootNavHost(
                     wallet = walletViewModel,
                     transfer = transferViewModel,
                     onContinueClick = { navController.popBackStack<Routes.TransferRoot>(inclusive = true) },
+                    onTransferUnavailable = { navController.popBackStack<Routes.TransferRoot>(inclusive = true) },
                 )
             }
             composableWithDefaultTransitions<Routes.SpendingIntro> {

app/src/main/java/to/bitkit/ui/screens/transfer/SavingsProgressScreen.kt

@@ -20,13 +20,15 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.layout.ContentScale
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import kotlinx.coroutines.delay
 import to.bitkit.R
+import to.bitkit.models.Toast
 import to.bitkit.ui.components.BodyM
 import to.bitkit.ui.components.Display
 import to.bitkit.ui.components.PrimaryButton
@@ -52,8 +54,10 @@ fun SavingsProgressScreen(
     transfer: TransferViewModel,
     wallet: WalletViewModel,
     onContinueClick: () -> Unit = {},
+    onTransferUnavailable: () -> Unit = {},
 ) {
     val window = LocalActivity.current?.window
+    val context = LocalContext.current
     var progressState by remember { mutableStateOf(SavingsProgressState.PROGRESS) }
 
     // Effect to close channels & update UI
@@ -68,11 +72,35 @@ fun SavingsProgressScreen(
             delay(5000)
             progressState = SavingsProgressState.SUCCESS
         } else {
-            transfer.startCoopCloseRetries(channelsFailedToCoopClose) {
-                app.showSheet(Sheet.ForceTransfer)
+            // Check if any channels can be retried (filter out trusted peers)
+            val (_, nonTrustedChannels) = transfer.separateTrustedChannels(channelsFailedToCoopClose)
+
+            if (nonTrustedChannels.isEmpty()) {
+                // All channels are trusted peers - show error and navigate back immediately
+                window?.clearFlags(FLAG_KEEP_SCREEN_ON)
+                app.toast(
+                    type = Toast.ToastType.ERROR,
+                    title = context.getString(R.string.lightning__close_error),
+                    description = context.getString(R.string.lightning__close_error_msg),
+                )
+                onTransferUnavailable()
+            } else {
+                transfer.startCoopCloseRetries(
+                    channels = nonTrustedChannels,
+                    onGiveUp = { app.showSheet(Sheet.ForceTransfer) },
+                    onTransferUnavailable = {
+                        window?.clearFlags(FLAG_KEEP_SCREEN_ON)
+                        app.toast(
+                            type = Toast.ToastType.ERROR,
+                            title = context.getString(R.string.lightning__close_error),
+                            description = context.getString(R.string.lightning__close_error_msg),
+                        )
+                        onTransferUnavailable()
+                    },
+                )
+                delay(2500)
+                progressState = SavingsProgressState.INTERRUPTED
             }
-            delay(2500)
-            progressState = SavingsProgressState.INTERRUPTED
         }
     }
 

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

@@ -374,6 +374,10 @@ class TransferViewModel @Inject constructor(
     /** Closes the channels selected earlier, pending closure */
     suspend fun closeSelectedChannels() = closeChannels(channelsToClose)
 
+    fun separateTrustedChannels(
+        channels: List<ChannelDetails>,
+    ): Pair<List<ChannelDetails>, List<ChannelDetails>> = lightningRepo.separateTrustedChannels(channels)
+
     private suspend fun closeChannels(channels: List<ChannelDetails>): List<ChannelDetails> {
         val channelsFailedToClose = coroutineScope {
             channels.map { channel ->
@@ -404,6 +408,7 @@ class TransferViewModel @Inject constructor(
     fun startCoopCloseRetries(
         channels: List<ChannelDetails>,
         onGiveUp: () -> Unit,
+        onTransferUnavailable: () -> Unit,
     ) {
         val startTimeMs = clock.now().toEpochMilliseconds()
         channelsToClose = channels
@@ -427,21 +432,63 @@ class TransferViewModel @Inject constructor(
                 delay(RETRY_INTERVAL_MS)
             }
 
-            Logger.info("Giving up on coop close.")
-            onGiveUp()
+            Logger.info("Giving up on coop close. Checking if force close is possible.", context = TAG)
+
+            // Check if any channels can be force closed (filter out trusted peers)
+            val (_, nonTrustedChannels) = lightningRepo.separateTrustedChannels(channelsToClose)
+
+            if (nonTrustedChannels.isNotEmpty()) {
+                onGiveUp()
+            } else {
+                Logger.warn("All channels are with trusted peers. Cannot force close.", context = TAG)
+                channelsToClose = emptyList()
+                onTransferUnavailable()
+            }
         }
     }
 
     fun forceTransfer(onComplete: () -> Unit) = viewModelScope.launch {
         _isForceTransferLoading.value = true
         runCatching {
-            val failedChannels = forceCloseChannels(channelsToClose)
+            // Filter out trusted peer channels (cannot force close LSP channels)
+            val (trustedChannels, nonTrustedChannels) = lightningRepo.separateTrustedChannels(channelsToClose)
+
+            if (trustedChannels.isNotEmpty()) {
+                Logger.warn("Skipping ${trustedChannels.size} trusted peer channel(s)", context = TAG)
+            }
+
+            if (nonTrustedChannels.isEmpty()) {
+                channelsToClose = emptyList()
+                Logger.error("Cannot force close channels with trusted peer", context = TAG)
+                ToastEventBus.send(
+                    type = Toast.ToastType.ERROR,
+                    title = context.getString(R.string.lightning__force_failed_title),
+                    description = context.getString(R.string.lightning__force_failed_msg)
+                )
+                return@runCatching
+            }
+
+            val failedChannels = forceCloseChannels(nonTrustedChannels)
+
+            // Remove successfully closed channels and trusted peer channels from the list
+            val successfulChannelIds = nonTrustedChannels
+                .filterNot { channel -> failedChannels.any { it.channelId == channel.channelId } }
+                .map { it.channelId }
+                .toSet()
+            val trustedChannelIds = trustedChannels.map { it.channelId }.toSet()
+            channelsToClose = channelsToClose.filterNot {
+                it.channelId in successfulChannelIds || it.channelId in trustedChannelIds
+            }
+
             if (failedChannels.isEmpty()) {
                 Logger.info("Force close initiated successfully for all channels", context = TAG)
+                val initMsg = context.getString(R.string.lightning__force_init_msg)
+                val skippedMsg = context.getString(R.string.lightning__force_channels_skipped)
+                val description = if (trustedChannels.isNotEmpty()) "$initMsg $skippedMsg" else initMsg
                 ToastEventBus.send(
                     type = Toast.ToastType.LIGHTNING,
                     title = context.getString(R.string.lightning__force_init_title),
-                    description = context.getString(R.string.lightning__force_init_msg)
+                    description = description,
                 )
             } else {
                 Logger.error("Force close failed for ${failedChannels.size} channels", context = TAG)
@@ -451,8 +498,8 @@ class TransferViewModel @Inject constructor(
                     description = context.getString(R.string.lightning__force_failed_msg)
                 )
             }
-        }.onFailure { e ->
-            Logger.error("Force close failed", e = e, context = TAG)
+        }.onFailure {
+            Logger.error("Force close failed", e = it, context = TAG)
             ToastEventBus.send(
                 type = Toast.ToastType.ERROR,
                 title = context.getString(R.string.lightning__force_failed_title),

app/src/main/res/values/strings.xml

@@ -254,6 +254,7 @@
     <string name="lightning__force_button">Force Transfer</string>
     <string name="lightning__force_init_title">Force Transfer Initiated</string>
     <string name="lightning__force_init_msg">Your funds will be accessible in ±14 days.</string>
+    <string name="lightning__force_channels_skipped">Some connections could not be closed.</string>
     <string name="lightning__force_failed_title">Force Transfer Failed</string>
     <string name="lightning__force_failed_msg">Unable to transfer your funds back to savings. Please try again.</string>
     <string name="lightning__channel_opened_title">Spending Balance Ready</string>