feat: show pending balances from channel closures (LDK)

frontend/src/screens/channels/Channels.tsx

@@ -7,6 +7,7 @@ import {
   CopyIcon,
   Heart,
   Hotel,
+  HourglassIcon,
   InfoIcon,
   Unplug,
 } from "lucide-react";
@@ -300,11 +301,15 @@ export default function Channels() {
                   {new Intl.NumberFormat().format(balances.onchain.spendable)}{" "}
                   sats
                   {balances &&
-                    balances.onchain.spendable !== balances.onchain.total && (
+                    (balances.onchain.spendable !== balances.onchain.total ||
+                      balances.onchain.pendingBalancesFromChannelClosures >
+                        0) && (
                       <p className="text-xs text-muted-foreground animate-pulse">
                         +
                         {new Intl.NumberFormat().format(
-                          balances.onchain.total - balances.onchain.spendable
+                          balances.onchain.total -
+                            balances.onchain.spendable +
+                            balances.onchain.pendingBalancesFromChannelClosures
                         )}{" "}
                         sats incoming
                       </p>
@@ -403,6 +408,27 @@ export default function Channels() {
         </Card>
       </div>
 
+      {balances && balances.onchain.pendingBalancesFromChannelClosures > 0 && (
+        <Alert>
+          <HourglassIcon className="h-4 w-4" />
+          <AlertTitle>Pending Closed Channels</AlertTitle>
+          <AlertDescription>
+            You have{" "}
+            {new Intl.NumberFormat().format(
+              balances.onchain.pendingBalancesFromChannelClosures
+            )}{" "}
+            sats pending from one or more closed channels. Once spendable again
+            these will become available in your savings balance.{" "}
+            <ExternalLink
+              to="https://guides.getalby.com/user-guide/v/alby-account-and-browser-extension/alby-hub/faq-alby-hub/why-was-my-lightning-channel-closed-and-what-to-do-next"
+              className="underline"
+            >
+              Learn more
+            </ExternalLink>
+          </AlertDescription>
+        </Alert>
+      )}
+
       {channels && channels.length === 0 && (
         <EmptyState
           icon={Unplug}

frontend/src/types.ts

@@ -269,6 +269,7 @@ export type OnchainBalanceResponse = {
   spendable: number;
   total: number;
   reserved: number;
+  pendingBalancesFromChannelClosures: number;
 };
 
 // from https://mempool.space/docs/api/rest#get-node-stats

lnclient/ldk/ldk.go

@@ -988,14 +988,57 @@ func (ls *LDKService) GetNewOnchainAddress(ctx context.Context) (string, error)
 }
 
 func (ls *LDKService) GetOnchainBalance(ctx context.Context) (*lnclient.OnchainBalanceResponse, error) {
+	channels := ls.node.ListChannels()
 	balances := ls.node.ListBalances()
 	logger.Logger.WithFields(logrus.Fields{
 		"balances": balances,
 	}).Debug("Listed Balances")
+
+	pendingBalancesFromChannelClosures := uint64(0)
+	// increase pending balance from any lightning balances for channels that are pending closure
+	// (they do not exist in our list of open channels)
+	for _, balance := range balances.LightningBalances {
+		increasePendingBalance := func(channelId string, amount uint64) {
+			if !slices.ContainsFunc(channels, func(channel ldk_node.ChannelDetails) bool {
+				return channel.ChannelId == channelId
+			}) {
+				pendingBalancesFromChannelClosures += amount
+			}
+		}
+
+		switch balanceType := (balance).(type) {
+		case ldk_node.LightningBalanceClaimableOnChannelClose:
+			increasePendingBalance(balanceType.ChannelId, balanceType.AmountSatoshis)
+		case ldk_node.LightningBalanceClaimableAwaitingConfirmations:
+			increasePendingBalance(balanceType.ChannelId, balanceType.AmountSatoshis)
+		case ldk_node.LightningBalanceContentiousClaimable:
+			increasePendingBalance(balanceType.ChannelId, balanceType.AmountSatoshis)
+		case ldk_node.LightningBalanceMaybeTimeoutClaimableHtlc:
+			increasePendingBalance(balanceType.ChannelId, balanceType.AmountSatoshis)
+		case ldk_node.LightningBalanceMaybePreimageClaimableHtlc:
+			increasePendingBalance(balanceType.ChannelId, balanceType.AmountSatoshis)
+		case ldk_node.LightningBalanceCounterpartyRevokedOutputClaimable:
+			increasePendingBalance(balanceType.ChannelId, balanceType.AmountSatoshis)
+		}
+	}
+
+	// increase pending balance from any lightning balances for channels that were closed
+	for _, balance := range balances.PendingBalancesFromChannelClosures {
+		switch pendingType := (balance).(type) {
+		case ldk_node.PendingSweepBalancePendingBroadcast:
+			pendingBalancesFromChannelClosures += pendingType.AmountSatoshis
+		case ldk_node.PendingSweepBalanceBroadcastAwaitingConfirmation:
+			pendingBalancesFromChannelClosures += pendingType.AmountSatoshis
+		case ldk_node.PendingSweepBalanceAwaitingThresholdConfirmations:
+			pendingBalancesFromChannelClosures += pendingType.AmountSatoshis
+		}
+	}
+
 	return &lnclient.OnchainBalanceResponse{
-		Spendable: int64(balances.SpendableOnchainBalanceSats),
-		Total:     int64(balances.TotalOnchainBalanceSats - balances.TotalAnchorChannelsReserveSats),
-		Reserved:  int64(balances.TotalAnchorChannelsReserveSats),
+		Spendable:                          int64(balances.SpendableOnchainBalanceSats),
+		Total:                              int64(balances.TotalOnchainBalanceSats - balances.TotalAnchorChannelsReserveSats),
+		Reserved:                           int64(balances.TotalAnchorChannelsReserveSats),
+		PendingBalancesFromChannelClosures: pendingBalancesFromChannelClosures,
 	}, nil
 }
 

lnclient/models.go

@@ -135,9 +135,10 @@ type CloseChannelResponse struct {
 }
 
 type OnchainBalanceResponse struct {
-	Spendable int64 `json:"spendable"`
-	Total     int64 `json:"total"`
-	Reserved  int64 `json:"reserved"`
+	Spendable                          int64  `json:"spendable"`
+	Total                              int64  `json:"total"`
+	Reserved                           int64  `json:"reserved"`
+	PendingBalancesFromChannelClosures uint64 `json:"pendingBalancesFromChannelClosures"`
 }
 
 type PeerDetails struct {