fix(lightning): never report a slow in-flight payment as failed

Slow multi-hop payments (>15s routing) surfaced as "Payment failed"
while LND settled them in the background: the shared LND REST client's
15s total timeout aborted the synchronous /v1/channels/transactions
wait, and every UI path treated that abort as a definitive failure. The
payment then succeeded anyway and only appeared in history on the next
background poll.

Backend: lnd.payinvoice now decodes the invoice up front for its payment
hash, pays on a dedicated 120s client, and answers status:"pending" with
the hash (never an error) when the wait elapses after the payment was
handed to LND — only a pre-connect failure is still a hard error. New
lnd.paymentstatus RPC reports succeeded/failed/in_flight (with humanized
failure reasons) from /v1/payments.

Frontend: new rpcClient.payLightningInvoice() pays then polls
lnd.paymentstatus to a real terminal state (3s interval, up to 2 min);
all five call sites (send modal, scan modal, web5 unified send, peer-file
purchase, app-launcher payments) migrated. Failure is only shown when LND
itself declares FAILED; a still-settling payment shows an in-flight state
and success fires the transaction refresh.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

neode-ui/src/api/rpc-client.ts

@@ -400,6 +400,76 @@ class RPCClient {
     })
   }
 
+  /** Pay a Lightning invoice and resolve it to a REAL terminal state.
+   *
+   * The backend waits up to 120s on LND's synchronous pay endpoint; if the
+   * payment is still routing after that it answers `status: "pending"` with
+   * the payment hash instead of an error. This helper then polls
+   * lnd.paymentstatus until LND itself reports succeeded/failed, so callers
+   * never show "failed" for a payment that is merely slow — the bug where a
+   * settling payment was declared failed and then appeared in history a
+   * minute later. Returns `pending` only if the payment is STILL in flight
+   * after the polling window (rare; caller should say "still settling",
+   * not "failed"). */
+  async payLightningInvoice(params: {
+    payment_request: string
+    amount_sats?: number
+  }): Promise<{
+    status: 'succeeded' | 'failed' | 'pending'
+    payment_hash: string
+    amount_sats: number
+    failure_reason?: string
+  }> {
+    const res = await this.call<{
+      status?: string
+      payment_hash?: string
+      amount_sats?: number
+    }>({
+      method: 'lnd.payinvoice',
+      params,
+      // Above the backend's 120s wait so the backend always answers first.
+      timeout: 130000,
+    })
+
+    const hash = res.payment_hash || ''
+    const amount = res.amount_sats || 0
+    // Older backends have no status field — a plain response was a success.
+    if (res.status !== 'pending') {
+      return { status: 'succeeded', payment_hash: hash, amount_sats: amount }
+    }
+    if (!hash) return { status: 'pending', payment_hash: '', amount_sats: amount }
+
+    // Poll to a terminal state: every 3s for up to 2 minutes.
+    for (let i = 0; i < 40; i++) {
+      await new Promise((r) => setTimeout(r, 3000))
+      try {
+        const st = await this.call<{
+          status: string
+          failure_reason?: string
+          amount_sats?: number
+        }>({
+          method: 'lnd.paymentstatus',
+          params: { payment_hash: hash },
+          timeout: 15000,
+        })
+        if (st.status === 'succeeded') {
+          return { status: 'succeeded', payment_hash: hash, amount_sats: st.amount_sats || amount }
+        }
+        if (st.status === 'failed') {
+          return {
+            status: 'failed',
+            payment_hash: hash,
+            amount_sats: amount,
+            failure_reason: st.failure_reason || 'Payment failed',
+          }
+        }
+      } catch {
+        // Transient poll error — keep trying; only LND decides failure.
+      }
+    }
+    return { status: 'pending', payment_hash: hash, amount_sats: amount }
+  }
+
   async publishNostrIdentity(): Promise<{ event_id: string; success: number; failed: number }> {
     return this.call({
       method: 'node.nostr-publish',

neode-ui/src/components/AppLauncherOverlay.vue

@@ -525,10 +525,10 @@ async function approvePayment() {
       receipt = { method: 'ecash', token: res.token, amount_sats: res.amount_sats }
     } else if (method === 'lightning') {
       if (pay.invoice) {
-        const res = await rpcClient.call<{ payment_hash: string; amount_sats: number }>({
-          method: 'lnd.payinvoice',
-          params: { payment_request: pay.invoice },
-        })
+        // Tracked to a real terminal state — slow routing is not a failure.
+        const res = await rpcClient.payLightningInvoice({ payment_request: pay.invoice })
+        if (res.status === 'failed') throw new Error(res.failure_reason || 'Payment failed')
+        if (res.status === 'pending') throw new Error('Payment is still settling — check your wallet transactions before retrying.')
         receipt = { method: 'lightning', payment_hash: res.payment_hash, amount_sats: res.amount_sats }
       } else {
         // Create and immediately return an invoice for the requester to display

neode-ui/src/components/SendBitcoinModal.vue

@@ -620,11 +620,21 @@ async function send() {
       ecashToken.value = res.token
     } else if (method === 'lightning') {
       if (!dest.value.trim()) { error.value = t('web5.pasteInvoice'); return }
-      const res = await rpcClient.call<{ payment_hash: string }>({
-        method: 'lnd.payinvoice',
-        params: { payment_request: dest.value.trim() },
-      })
-      successInfo.value = { amount: paidAmount, methodLabel: 'Paid over Lightning', hash: res.payment_hash }
+      // Waits out slow multi-hop routing and only reports failure when LND
+      // itself declares the payment failed — never on a timeout.
+      const res = await rpcClient.payLightningInvoice({ payment_request: dest.value.trim() })
+      if (res.status === 'failed') {
+        error.value = res.failure_reason || t('web5.sendFailed')
+        return
+      }
+      successInfo.value = {
+        amount: paidAmount,
+        methodLabel: res.status === 'pending' ? 'Payment in flight' : 'Paid over Lightning',
+        hash: res.payment_hash || undefined,
+        ...(res.status === 'pending'
+          ? { note: 'This payment is taking longer than usual to settle. It will appear in your transactions once it completes.' }
+          : {}),
+      }
     } else {
       if (!dest.value.trim()) { error.value = t('web5.enterBitcoinAddress'); return }
       const res = await rpcClient.call<{ txid: string }>({

neode-ui/src/components/WalletScanModal.vue

@@ -701,16 +701,17 @@ async function confirmSend() {
   error.value = ''
   try {
     if (action.value === 'pay-invoice') {
-      const params: Record<string, unknown> = { payment_request: dest.value }
+      const params: { payment_request: string; amount_sats?: number } = { payment_request: dest.value }
       if (!amountLocked.value && effectiveAmount.value > 0) params.amount_sats = effectiveAmount.value
-      const res = await rpcClient.call<{ payment_hash: string; amount_sats: number }>({
-        method: 'lnd.payinvoice',
-        params,
-        timeout: 60000,
-      })
+      // Waits out slow multi-hop routing and only reports failure when LND
+      // itself declares the payment failed — never on a timeout.
+      const res = await rpcClient.payLightningInvoice(params)
+      if (res.status === 'failed') throw new Error(res.failure_reason || 'Payment failed')
       successAmount.value = res.amount_sats || effectiveAmount.value
-      successVerb.value = 'PAID'
-      successDetail.value = 'Lightning invoice paid'
+      successVerb.value = res.status === 'pending' ? 'SENDING' : 'PAID'
+      successDetail.value = res.status === 'pending'
+        ? 'Payment in flight — it will appear in your transactions once it settles'
+        : 'Lightning invoice paid'
       successRef.value = res.payment_hash
     } else if (action.value === 'send-onchain') {
       const res = await rpcClient.call<{ txid: string }>({

neode-ui/src/views/PeerFiles.vue

@@ -1320,8 +1320,8 @@ async function payWithInvoice() {
 
 /**
  * Pay the seller's invoice straight from THIS node's Lightning wallet, then
- * release the file. No QR/polling: lnd.payinvoice only returns once the payment
- * settles, so the payment_hash is immediately valid as the download gate token.
+ * release the file. payLightningInvoice resolves to a real terminal state, so
+ * on success the payment_hash is immediately valid as the download gate token.
  */
 async function payWithLightning() {
   const item = payItem.value
@@ -1341,14 +1341,15 @@ async function payWithLightning() {
       lnError.value = inv?.error || 'The seller could not create an invoice (is its Lightning node running?).'
       return
     }
-    // 2. Pay it from our own node. Returns only after settlement.
-    const pay = await rpcClient.call<{ payment_hash?: string; payment_error?: string }>({
-      method: 'lnd.payinvoice',
-      params: { payment_request: inv.bolt11 },
-      timeout: 120000,
-    })
-    if (pay?.payment_error) {
-      lnError.value = `Payment failed: ${pay.payment_error}`
+    // 2. Pay it from our own node. Tracked to a REAL terminal state — a slow
+    // multi-hop route resolves via status polling instead of a false failure.
+    const pay = await rpcClient.payLightningInvoice({ payment_request: inv.bolt11 })
+    if (pay.status === 'failed') {
+      lnError.value = `Payment failed: ${pay.failure_reason || 'unknown reason'}`
+      return
+    }
+    if (pay.status === 'pending') {
+      lnError.value = 'Payment is still settling — this can take a few minutes. Check your wallet transactions before paying again.'
       return
     }
     // 3. Settled — pull the file using the payment hash as the gate token.

neode-ui/src/views/web5/Web5SendReceiveModals.vue

@@ -291,10 +291,10 @@ async function unifiedSend() {
         unifiedSendError.value = t('web5.pasteInvoice')
         return
       }
-      const res = await rpcClient.call<{ payment_hash: string; amount_sats: number }>({
-        method: 'lnd.payinvoice',
-        params: { payment_request: unifiedSendDest.value.trim() },
-      })
+      // Waits out slow multi-hop routing and only reports failure when LND
+      // itself declares the payment failed — never on a timeout.
+      const res = await rpcClient.payLightningInvoice({ payment_request: unifiedSendDest.value.trim() })
+      if (res.status === 'failed') throw new Error(res.failure_reason || 'Payment failed')
       sendResultHash.value = res.payment_hash
     } else {
       if (!unifiedSendDest.value.trim()) {