Merge pull request #9792 from accumulator/qml_issue_noamt_lninvoice_sticky_override_amt

qml: fix storing override amount too soon, while user is allowed to set a new override amount which was silently ignored.

electrum/gui/qml/components/InvoiceDialog.qml

@@ -487,10 +487,6 @@ ElDialog {
                         if (amountMax.checked)
                             invoice.amountOverride.isMax = true
                     }
-                    if (!invoice.isSaved) {
-                        // save invoice if newly parsed
-                        invoice.saveInvoice()
-                    }
                     doPay() // only signal here
                 }
             }
@@ -506,9 +502,6 @@ ElDialog {
         }
         if (payImmediately) {
             if (invoice.canPay) {
-                if (!invoice.isSaved) {
-                    invoice.saveInvoice()
-                }
                 doPay()
             }
         }

electrum/gui/qml/components/WalletMainView.qml

@@ -114,6 +114,7 @@ Item {
         })
         var canComplete = !Daemon.currentWallet.isWatchOnly && Daemon.currentWallet.canSignWithoutCosigner
         dialog.accepted.connect(function() {
+            invoice.saveInvoice()
             if (!canComplete) {
                 if (Daemon.currentWallet.isWatchOnly) {
                     dialog.finalizer.saveOrShow()

electrum/gui/qml/qeinvoice.py

@@ -1,3 +1,4 @@
+import copy
 import threading
 from enum import IntEnum
 from typing import Optional, Dict, Any
@@ -213,14 +214,11 @@ class QEInvoice(QObject, QtEventListener):
 
     @key.setter
     def key(self, key):
-        if self._key != key:
-            self._key = key
-            if self._effectiveInvoice and self._effectiveInvoice.get_id() == key:
-                return
-            invoice = self._wallet.wallet.get_invoice(key)
-            self._logger.debug(f'invoice from key {key}: {repr(invoice)}')
-            self.set_effective_invoice(invoice)
-            self.keyChanged.emit()
+        self._key = key
+        invoice = copy.copy(self._wallet.wallet.get_invoice(key))  # copy, so any mutations stay out of wallet invoice list
+        self._logger.debug(f'invoice from key {key}: {repr(invoice)}')
+        self.set_effective_invoice(invoice)
+        self.keyChanged.emit()
 
     userinfoChanged = pyqtSignal()
     @pyqtProperty(str, notify=userinfoChanged)
@@ -386,12 +384,13 @@ class QEInvoice(QObject, QtEventListener):
         if self.invoiceType != QEInvoice.Type.LightningInvoice:
             raise Exception('payLightningInvoice can only pay lightning invoices')
 
+        amount_msat = None
         if self.amount.isEmpty:
             if self.amountOverride.isEmpty:
                 raise Exception('can not pay 0 amount')
-            self._effectiveInvoice.set_amount_msat(self.amountOverride.satsInt * 1000)
+            amount_msat = self.amountOverride.satsInt * 1000
 
-        self._wallet.pay_lightning_invoice(self._effectiveInvoice)
+        self._wallet.pay_lightning_invoice(self._effectiveInvoice, amount_msat)
 
     def get_max_spendable_onchain(self):
         spendable = self._wallet.confirmedBalance.satsInt
@@ -505,6 +504,7 @@ class QEInvoiceParser(QEInvoice):
         self._logger.debug('setValidLightningInvoice')
         if not invoice.is_lightning():
             raise Exception('unexpected Onchain invoice')
+        self._key = invoice.get_id()
         self.set_effective_invoice(invoice)
 
     def setValidLNURLPayRequest(self):
@@ -707,6 +707,6 @@ class QEInvoiceParser(QEInvoice):
         self.canSave = False
 
         self._wallet.wallet.save_invoice(self._effectiveInvoice)
-        self.key = self._effectiveInvoice.get_id()
-        self._wallet.invoiceModel.addInvoice(self.key)
-        self.invoiceSaved.emit(self.key)
+        self._key = self._effectiveInvoice.get_id()
+        self._wallet.invoiceModel.addInvoice(self._key)
+        self.invoiceSaved.emit(self._key)

electrum/gui/qml/qeinvoicelistmodel.py

@@ -132,7 +132,7 @@ class QEAbstractInvoiceListModel(QAbstractListModel):
             item['address'] = ''
         item['date'] = format_time(item['timestamp'])
         item['amount'] = QEAmount(from_invoice=invoice)
-        item['onchain_fallback'] = invoice.is_lightning() and invoice.get_address()
+        item['onchain_fallback'] = invoice.is_lightning() and bool(invoice.get_address())
 
         return item
 

electrum/gui/qml/qewallet.py

@@ -656,8 +656,23 @@ class QEWallet(AuthMixin, QObject, QtEventListener):
         self.paymentAuthRejected.emit()
 
     @auth_protect(message=_('Pay lightning invoice?'), reject='ln_auth_rejected')
-    def pay_lightning_invoice(self, invoice: 'Invoice'):
-        amount_msat = invoice.get_amount_msat()
+    def pay_lightning_invoice(self, invoice: 'Invoice', amount_msat: int = None):
+        # at this point, the user confirmed the payment, potentially with an override amount.
+        # we save the invoice with the override amount if there was no amount defined in the invoice.
+        # (this is similar to what the desktop client does)
+        #
+        # Note: amount_msat can be greater than the invoice-specified amount. This is validated and handled
+        # in lnworker.pay_invoice()
+        if amount_msat is not None:
+            assert type(amount_msat) is int
+            if invoice.get_amount_msat() is None:
+                invoice.set_amount_msat(amount_msat)
+        else:
+            amount_msat = invoice.get_amount_msat()
+
+        self.wallet.save_invoice(invoice)
+        if self._invoiceModel:
+            self._invoiceModel.initModel()
 
         def pay_thread():
             try: