From 43c6f450408b2c34e2cf0efd91c4b6f78a855d04 Mon Sep 17 00:00:00 2001
From: Sander van Grieken <sander@outrightsolutions.nl>
Date: Tue, 12 Aug 2025 11:10:36 +0200
Subject: [PATCH] qml: handle invoice validation errors on save

---
 electrum/gui/qml/components/InvoiceDialog.qml |  7 +++---
 .../gui/qml/components/WalletMainView.qml     |  9 +++++--
 electrum/gui/qml/qeinvoice.py                 | 25 ++++++++++++-------
 3 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/electrum/gui/qml/components/InvoiceDialog.qml b/electrum/gui/qml/components/InvoiceDialog.qml
index 80bb7a535..59590c622 100644
--- a/electrum/gui/qml/components/InvoiceDialog.qml
+++ b/electrum/gui/qml/components/InvoiceDialog.qml
@@ -470,9 +470,10 @@ ElDialog {
                         if (amountMax.checked)
                             invoice.amountOverride.isMax = true
                     }
-                    invoice.saveInvoice()
-                    app.stack.push(Qt.resolvedUrl('Invoices.qml'))
-                    dialog.close()
+                    if (invoice.saveInvoice()) {
+                        app.stack.push(Qt.resolvedUrl('Invoices.qml'))
+                        dialog.close()
+                    }
                 }
             }
             FlatButton {
diff --git a/electrum/gui/qml/components/WalletMainView.qml b/electrum/gui/qml/components/WalletMainView.qml
index b044d5189..d87bbd4bf 100644
--- a/electrum/gui/qml/components/WalletMainView.qml
+++ b/electrum/gui/qml/components/WalletMainView.qml
@@ -114,7 +114,8 @@ Item {
         var canComplete = !Daemon.currentWallet.isWatchOnly && Daemon.currentWallet.canSignWithoutCosigner
         dialog.accepted.connect(function() {
             if (invoice.canSave)
-                invoice.saveInvoice()
+                if (!invoice.saveInvoice())
+                    return
             if (!canComplete) {
                 if (Daemon.currentWallet.isWatchOnly) {
                     dialog.finalizer.saveOrShow()
@@ -413,7 +414,11 @@ Item {
             dialog.open()
         }
         onInvoiceCreateError: (code, message) => {
-            console.log(code + ' ' + message)
+            var msg = qsTr('Cannot save invoice') + ': ' + message
+            var dialog = app.messageDialog.createObject(app, {
+                text: msg
+            })
+            dialog.open()
         }
 
         onLnurlRetrieved: {
diff --git a/electrum/gui/qml/qeinvoice.py b/electrum/gui/qml/qeinvoice.py
index 12b6d2251..9e8d14aaf 100644
--- a/electrum/gui/qml/qeinvoice.py
+++ b/electrum/gui/qml/qeinvoice.py
@@ -23,6 +23,7 @@ from .qetypes import QEAmount
 from .qewallet import QEWallet
 from .util import status_update_timer_interval, QtEventListener, event_listener
 from ...fee_policy import FeePolicy
+from ...util import InvoiceError
 
 
 class QEInvoice(QObject, QtEventListener):
@@ -690,18 +691,22 @@ class QEInvoiceParser(QEInvoice):
 
         self.recipient = invoice.lightning_invoice
 
-    @pyqtSlot()
-    def saveInvoice(self):
+    @pyqtSlot(result=bool)
+    def saveInvoice(self) -> bool:
         if not self._effectiveInvoice:
-            return
+            return False
         if self.isSaved:
-            return
+            return False
 
-        if not self._effectiveInvoice.amount_msat and not self.amountOverride.isEmpty:
-            if self.invoiceType == QEInvoice.Type.OnchainInvoice and self.amountOverride.isMax:
-                self._effectiveInvoice.set_amount_msat('!')
-            else:
-                self._effectiveInvoice.set_amount_msat(self.amountOverride.satsInt * 1000)
+        try:
+            if not self._effectiveInvoice.amount_msat and not self.amountOverride.isEmpty:
+                if self.invoiceType == QEInvoice.Type.OnchainInvoice and self.amountOverride.isMax:
+                    self._effectiveInvoice.set_amount_msat('!')
+                else:
+                    self._effectiveInvoice.set_amount_msat(self.amountOverride.satsInt * 1000)
+        except InvoiceError as e:
+            self.invoiceCreateError.emit('validation', str(e))
+            return False
 
         self.canSave = False
 
@@ -709,3 +714,5 @@ class QEInvoiceParser(QEInvoice):
         self._key = self._effectiveInvoice.get_id()
         self._wallet.invoiceModel.addInvoice(self._key)
         self.invoiceSaved.emit(self._key)
+
+        return True