qt: refactor send_tab, paytoedit

electrum/gui/qt/amountedit.py

@@ -13,7 +13,6 @@ from electrum.util import (format_satoshis_plain, decimal_point_to_base_unit_nam
                            FEERATE_PRECISION, quantize_feerate, DECIMAL_POINT)
 from electrum.bitcoin import COIN, TOTAL_COIN_SUPPLY_LIMIT_IN_BTC
 
-
 _NOT_GIVEN = object()  # sentinel value
 
 

electrum/gui/qt/paytoedit.py

@@ -26,6 +26,8 @@
 from functools import partial
 from typing import NamedTuple, Sequence, Optional, List, TYPE_CHECKING
 
+from PyQt5.QtCore import Qt
+from PyQt5.QtCore import QObject, pyqtSignal
 from PyQt5.QtGui import QFontMetrics, QFont
 from PyQt5.QtWidgets import QApplication, QWidget, QLineEdit, QTextEdit, QVBoxLayout
 
@@ -48,6 +50,10 @@ frozen_style = "QWidget {border:none;}"
 normal_style = "QPlainTextEdit { }"
 
 
+class InvalidPaymentIdentifier(Exception):
+    pass
+
+
 class ResizingTextEdit(QTextEdit):
 
     def __init__(self):
@@ -63,113 +69,139 @@ class ResizingTextEdit(QTextEdit):
         self.verticalMargins += documentMargin * 2
         self.heightMin = self.fontSpacing + self.verticalMargins
         self.heightMax = (self.fontSpacing * 10) + self.verticalMargins
+        self.single_line = True
         self.update_size()
 
     def update_size(self):
         docLineCount = self.document().lineCount()
-        docHeight = max(3, docLineCount) * self.fontSpacing
+        docHeight = max(1 if self.single_line else 3, docLineCount) * self.fontSpacing
         h = docHeight + self.verticalMargins
         h = min(max(h, self.heightMin), self.heightMax)
         self.setMinimumHeight(int(h))
         self.setMaximumHeight(int(h))
-        self.verticalScrollBar().setHidden(docHeight + self.verticalMargins < self.heightMax)
+        if self.single_line:
+            self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
+            self.setLineWrapMode(QTextEdit.LineWrapMode.NoWrap)
+        else:
+            self.setHorizontalScrollBarPolicy(Qt.ScrollBarAsNeeded)
+            self.verticalScrollBar().setHidden(docHeight + self.verticalMargins < self.heightMax)
+            self.setLineWrapMode(QTextEdit.LineWrapMode.WidgetWidth)
 
+class PayToEdit(QObject, Logger, GenericInputHandler):
 
-class PayToEdit(Logger, GenericInputHandler):
+    paymentIdentifierChanged = pyqtSignal()
 
     def __init__(self, send_tab: 'SendTab'):
+        QObject.__init__(self, parent=send_tab)
         Logger.__init__(self)
         GenericInputHandler.__init__(self)
-        self.line_edit = QLineEdit()
+
         self.text_edit = ResizingTextEdit()
-        self.text_edit.hide()
+        self.text_edit.textChanged.connect(self._on_text_edit_text_changed)
         self._is_paytomany = False
-        for w in [self.line_edit, self.text_edit]:
-            w.setFont(QFont(MONOSPACE_FONT))
-            w.textChanged.connect(self._on_text_changed)
+        self.text_edit.setFont(QFont(MONOSPACE_FONT))
         self.send_tab = send_tab
         self.config = send_tab.config
-        self.win = send_tab.window
         self.app = QApplication.instance()
-        self.amount_edit = self.send_tab.amount_e
 
+        self.logger.debug(util.ColorScheme.RED.as_stylesheet(True))
         self.is_multiline = False
-        self.disable_checks = False
-        self.is_alias = False
+        # self.is_alias = False
         self.payto_scriptpubkey = None  # type: Optional[bytes]
         self.previous_payto = ''
         # editor methods
-        self.setStyleSheet = self.editor.setStyleSheet
-        self.setText = self.editor.setText
-        self.setEnabled = self.editor.setEnabled
-        self.setReadOnly = self.editor.setReadOnly
-        self.setFocus = self.editor.setFocus
+        self.setStyleSheet = self.text_edit.setStyleSheet
+        self.setText = self.text_edit.setText
+        self.setFocus = self.text_edit.setFocus
+        self.setToolTip = self.text_edit.setToolTip
         # button handlers
         self.on_qr_from_camera_input_btn = partial(
             self.input_qr_from_camera,
             config=self.config,
             allow_multi=False,
-            show_error=self.win.show_error,
-            setText=self._on_input_btn,
-            parent=self.win,
+            show_error=self.send_tab.show_error,
+            setText=self.try_payment_identifier,
+            parent=self.send_tab.window,
         )
         self.on_qr_from_screenshot_input_btn = partial(
             self.input_qr_from_screenshot,
             allow_multi=False,
-            show_error=self.win.show_error,
-            setText=self._on_input_btn,
+            show_error=self.send_tab.show_error,
+            setText=self.try_payment_identifier,
         )
         self.on_input_file = partial(
             self.input_file,
             config=self.config,
-            show_error=self.win.show_error,
-            setText=self._on_input_btn,
+            show_error=self.send_tab.show_error,
+            setText=self.try_payment_identifier,
         )
-        #
-        self.line_edit.contextMenuEvent = partial(editor_contextMenuEvent, self.line_edit, self)
+
         self.text_edit.contextMenuEvent = partial(editor_contextMenuEvent, self.text_edit, self)
 
-    @property
-    def editor(self):
-        return self.text_edit if self.is_paytomany() else self.line_edit
+        self.payment_identifier = None
+
+    def set_text(self, text: str):
+        self.text_edit.setText(text)
+
+    def update_editor(self):
+        if self.text_edit.toPlainText() != self.payment_identifier.text:
+            self.text_edit.setText(self.payment_identifier.text)
+        self.text_edit.single_line = not self.payment_identifier.is_multiline()
+        self.text_edit.update_size()
+
+    '''set payment identifier only if valid, else exception'''
+    def try_payment_identifier(self, text):
+        text = text.strip()
+        pi = PaymentIdentifier(self.send_tab.wallet, text)
+        if not pi.is_valid():
+            raise InvalidPaymentIdentifier('Invalid payment identifier')
+        self.set_payment_identifier(text)
+
+    def set_payment_identifier(self, text):
+        text = text.strip()
+        if self.payment_identifier and self.payment_identifier.text == text:
+            # no change.
+            return
+
+        self.payment_identifier = PaymentIdentifier(self.send_tab.wallet, text)
+
+        # toggle to multiline if payment identifier is a multiline
+        self.is_multiline = self.payment_identifier.is_multiline()
+        self.logger.debug(f'is_multiline {self.is_multiline}')
+        if self.is_multiline and not self._is_paytomany:
+            self.set_paytomany(True)
+
+        # if payment identifier gets set externally, we want to update the text_edit
+        # Note: this triggers the change handler, but we shortcut if it's the same payment identifier
+        self.update_editor()
+
+        self.paymentIdentifierChanged.emit()
 
     def set_paytomany(self, b):
-        has_focus = self.editor.hasFocus()
         self._is_paytomany = b
-        self.line_edit.setVisible(not b)
-        self.text_edit.setVisible(b)
+        self.text_edit.single_line = not self._is_paytomany
+        self.text_edit.update_size()
         self.send_tab.paytomany_menu.setChecked(b)
-        if has_focus:
-            self.editor.setFocus()
 
     def toggle_paytomany(self):
         self.set_paytomany(not self._is_paytomany)
 
-    def toPlainText(self):
-        return self.text_edit.toPlainText() if self.is_paytomany() else self.line_edit.text()
-
     def is_paytomany(self):
         return self._is_paytomany
 
     def setFrozen(self, b):
-        self.setReadOnly(b)
+        self.text_edit.setReadOnly(b)
         if not b:
             self.setStyleSheet(normal_style)
 
-    def setTextNoCheck(self, text: str):
-        """Sets the text, while also ensuring the new value will not be resolved/checked."""
-        self.previous_payto = text
-        self.setText(text)
+    def isFrozen(self):
+        return self.text_edit.isReadOnly()
 
     def do_clear(self):
         self.is_multiline = False
         self.set_paytomany(False)
-        self.disable_checks = False
-        self.is_alias = False
-        self.line_edit.setText('')
         self.text_edit.setText('')
-        self.setFrozen(False)
-        self.setEnabled(True)
+        self.payment_identifier = None
 
     def setGreen(self):
         self.setStyleSheet(util.ColorScheme.GREEN.as_stylesheet(True))
@@ -177,53 +209,18 @@ class PayToEdit(Logger, GenericInputHandler):
     def setExpired(self):
         self.setStyleSheet(util.ColorScheme.RED.as_stylesheet(True))
 
-    def _on_input_btn(self, text: str):
-        self.setText(text)
-
-    def _on_text_changed(self):
-        text = self.toPlainText()
-        # False if user pasted from clipboard
-        full_check = self.app.clipboard().text() != text
-        self._check_text(text, full_check=full_check)
-        if self.is_multiline and not self._is_paytomany:
-            self.set_paytomany(True)
-            self.text_edit.setText(text)
-            self.text_edit.setFocus()
+    def _on_text_edit_text_changed(self):
+        self._handle_text_change(self.text_edit.toPlainText())
 
-    def _check_text(self, text, *, full_check: bool):
-        """ side effects: self.is_multiline """
-        text = str(text).strip()
-        if not text:
+    def _handle_text_change(self, text):
+        if self.isFrozen():
+            # if editor is frozen, we ignore text changes as they might not be a payment identifier
+            # but a user friendly representation.
             return
-        if self.previous_payto == text:
-            return
-        if full_check:
-            self.previous_payto = text
-        if self.disable_checks:
-            return
-        pi = PaymentIdentifier(self.send_tab.wallet, text)
-        self.is_multiline = bool(pi.multiline_outputs) # TODO: why both is_multiline and set_paytomany(True)??
-        self.logger.debug(f'is_multiline {self.is_multiline}')
-        if pi.is_valid():
-            self.send_tab.set_payment_identifier(text)
-        else:
-            if not full_check and pi.error:
-                self.send_tab.show_error(
-                    _('Clipboard text is not a valid payment identifier') + '\n' + str(pi.error))
-                return
-
-    def handle_multiline(self, outputs):
-        total = 0
-        is_max = False
-        for output in outputs:
-            if parse_max_spend(output.value):
-                is_max = True
-            else:
-                total += output.value
-        self.send_tab.set_onchain(True)
-        self.send_tab.max_button.setChecked(is_max)
-        if self.send_tab.max_button.isChecked():
-            self.send_tab.spend_max()
-        else:
-            self.amount_edit.setAmount(total if outputs else None)
-        #self.send_tab.lock_amount(self.send_tab.max_button.isChecked() or bool(outputs))
+
+        self.set_payment_identifier(text)
+        if self.app.clipboard().text() and self.app.clipboard().text().strip() == self.payment_identifier.text:
+            # user pasted from clipboard
+            self.logger.debug('from clipboard')
+            if self.payment_identifier.error:
+                self.send_tab.show_error(_('Clipboard text is not a valid payment identifier') + '\n' + self.payment_identifier.error)

electrum/gui/qt/send_tab.py

@@ -6,14 +6,13 @@ import asyncio
 from decimal import Decimal
 from typing import Optional, TYPE_CHECKING, Sequence, List, Callable
 from PyQt5.QtCore import pyqtSignal, QPoint
-from PyQt5.QtWidgets import (QLabel, QVBoxLayout, QGridLayout,
-                             QHBoxLayout, QCompleter, QWidget, QToolTip, QPushButton)
+from PyQt5.QtWidgets import (QLabel, QVBoxLayout, QGridLayout, QHBoxLayout,
+                             QWidget, QToolTip, QPushButton, QApplication)
 
 from electrum.plugin import run_hook
 from electrum.i18n import _
 
 from electrum.util import NotEnoughFunds, NoDynamicFeeEstimates, parse_max_spend
-from electrum.payment_identifier import PaymentIdentifier
 from electrum.invoices import PR_PAID, Invoice, PR_BROADCASTING, PR_BROADCAST
 
 from electrum.transaction import Transaction, PartialTxInput, PartialTxOutput
@@ -21,8 +20,10 @@ from electrum.network import TxBroadcastError, BestEffortRequestFailed
 from electrum.logging import Logger
 
 from .amountedit import AmountEdit, BTCAmountEdit, SizedFreezableLineEdit
-from .util import WaitingDialog, HelpLabel, MessageBoxMixin, EnterButton, char_width_in_lineedit
-from .util import get_iconname_camera, get_iconname_qrcode, read_QIcon
+from .paytoedit import InvalidPaymentIdentifier
+from .util import (WaitingDialog, HelpLabel, MessageBoxMixin, EnterButton,
+                   char_width_in_lineedit, get_iconname_camera, get_iconname_qrcode,
+                   read_QIcon)
 from .confirm_tx_dialog import ConfirmTxDialog
 
 if TYPE_CHECKING:
@@ -38,7 +39,7 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
     def __init__(self, window: 'ElectrumWindow'):
         QWidget.__init__(self, window)
         Logger.__init__(self)
-
+        self.app = QApplication.instance()
         self.window = window
         self.wallet = window.wallet
         self.fx = window.fx
@@ -49,7 +50,6 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         self.format_amount = window.format_amount
         self.base_unit = window.base_unit
 
-        self.payment_identifier = None
         self.pending_invoice = None
 
         # A 4-column grid layout.  All the stretch is in the last column.
@@ -73,7 +73,7 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
                    "e.g. set one amount to '2!' and another to '3!' to split your coins 40-60."))
         payto_label = HelpLabel(_('Pay to'), msg)
         grid.addWidget(payto_label, 0, 0)
-        grid.addWidget(self.payto_e.line_edit, 0, 1, 1, 4)
+        # grid.addWidget(self.payto_e.line_edit, 0, 1, 1, 4)
         grid.addWidget(self.payto_e.text_edit, 0, 1, 1, 4)
 
         #completer = QCompleter()
@@ -119,11 +119,9 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         btn_width = 10 * char_width_in_lineedit()
         self.max_button.setFixedWidth(btn_width)
         self.max_button.setCheckable(True)
+        self.max_button.setEnabled(False)
         grid.addWidget(self.max_button, 3, 3)
 
-        self.save_button = EnterButton(_("Save"), self.do_save_invoice)
-        self.send_button = EnterButton(_("Pay") + "...", self.do_pay_or_get_invoice)
-        self.clear_button = EnterButton(_("Clear"), self.do_clear)
         self.paste_button = QPushButton()
         self.paste_button.clicked.connect(self.do_paste)
         self.paste_button.setIcon(read_QIcon('copy.png'))
@@ -131,9 +129,15 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         self.paste_button.setMaximumWidth(35)
         grid.addWidget(self.paste_button, 0, 5)
 
+        self.save_button = EnterButton(_("Save"), self.do_save_invoice)
+        self.save_button.setEnabled(False)
+        self.send_button = EnterButton(_("Pay") + "...", self.do_pay_or_get_invoice)
+        self.send_button.setEnabled(False)
+        self.clear_button = EnterButton(_("Clear"), self.do_clear)
+
         buttons = QHBoxLayout()
         buttons.addStretch(1)
-        #buttons.addWidget(self.paste_button)
+
         buttons.addWidget(self.clear_button)
         buttons.addWidget(self.save_button)
         buttons.addWidget(self.send_button)
@@ -143,14 +147,11 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
 
         def reset_max(text):
             self.max_button.setChecked(False)
-            enable = not bool(text) and not self.amount_e.isReadOnly()
-            # self.max_button.setEnabled(enable)
 
+        self.amount_e.textChanged.connect(self.on_amount_changed)
         self.amount_e.textEdited.connect(reset_max)
         self.fiat_send_e.textEdited.connect(reset_max)
 
-        self.set_onchain(False)
-
         self.invoices_label = QLabel(_('Invoices'))
         from .invoice_list import InvoiceList
         self.invoice_list = InvoiceList(self)
@@ -184,30 +185,33 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         self.resolve_done_signal.connect(self.on_resolve_done)
         self.finalize_done_signal.connect(self.on_finalize_done)
         self.notify_merchant_done_signal.connect(self.on_notify_merchant_done)
+        self.payto_e.paymentIdentifierChanged.connect(self._handle_payment_identifier)
+
+    def on_amount_changed(self, text):
+        # FIXME: implement full valid amount check to enable/disable Pay button
+        pi_valid = self.payto_e.payment_identifier.is_valid() if self.payto_e.payment_identifier else False
+        self.send_button.setEnabled(bool(self.amount_e.get_amount()) and pi_valid)
+
 
     def do_paste(self):
-        text = self.window.app.clipboard().text()
-        if not text:
-            return
-        self.set_payment_identifier(text)
+        try:
+            self.payto_e.try_payment_identifier(self.app.clipboard().text())
+        except InvalidPaymentIdentifier as e:
+            self.show_error(_('Invalid payment identifier on clipboard'))
 
     def set_payment_identifier(self, text):
-        self.payment_identifier = PaymentIdentifier(self.wallet, text)
-        if self.payment_identifier.error:
-            self.show_error(_('Clipboard text is not a valid payment identifier') + '\n' + self.payment_identifier.error)
-            return
-        if self.payment_identifier.is_multiline():
-            self.payto_e.set_paytomany(True)
-            self.payto_e.text_edit.setText(text)
-        else:
-            self.payto_e.setTextNoCheck(text)
-        self._handle_payment_identifier(can_use_network=True)
+        self.logger.debug('set_payment_identifier')
+        try:
+            self.payto_e.try_payment_identifier(text)
+        except InvalidPaymentIdentifier as e:
+            self.show_error(_('Invalid payment identifier'))
 
     def spend_max(self):
+        assert self.payto_e.payment_identifier is not None
+        assert self.payto_e.payment_identifier.type in ['spk', 'multiline']
         if run_hook('abort_send', self):
             return
-        amount = self.get_amount()
-        outputs = self.payment_identifier.get_onchain_outputs(amount)
+        outputs = self.payto_e.payment_identifier.get_onchain_outputs('!')
         if not outputs:
             return
         make_tx = lambda fee_est, *, confirmed_only=False: self.wallet.make_unsigned_transaction(
@@ -296,9 +300,7 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         text = _("Not enough funds")
         frozen_str = self.get_frozen_balance_str()
         if frozen_str:
-            text += " ({} {})".format(
-                frozen_str, _("are frozen")
-            )
+            text += " ({} {})".format(frozen_str, _("are frozen"))
         return text
 
     def get_frozen_balance_str(self) -> Optional[str]:
@@ -308,31 +310,26 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         return self.format_amount_and_units(frozen_bal)
 
     def do_clear(self):
+        self.lock_fields(lock_recipient=False, lock_amount=False, lock_max=True, lock_description=False)
         self.max_button.setChecked(False)
         self.payto_e.do_clear()
-        self.set_onchain(False)
         for w in [self.comment_e, self.comment_label]:
             w.setVisible(False)
         for e in [self.message_e, self.amount_e, self.fiat_send_e]:
             e.setText('')
             self.set_field_style(e, None, False)
-        for e in [self.send_button, self.save_button, self.clear_button, self.amount_e, self.fiat_send_e]:
-            e.setEnabled(True)
+        for e in [self.save_button, self.send_button]:
+            e.setEnabled(False)
         self.window.update_status()
         run_hook('do_clear', self)
 
-    def set_onchain(self, b):
-        self._is_onchain = b
-        self.max_button.setEnabled(b)
-
     def prepare_for_send_tab_network_lookup(self):
         self.window.show_send_tab()
-        self.payto_e.disable_checks = True
         #for e in [self.payto_e, self.message_e]:
-        self.payto_e.setFrozen(True)
+        # self.payto_e.setFrozen(True)
         for btn in [self.save_button, self.send_button, self.clear_button]:
             btn.setEnabled(False)
-        self.payto_e.setTextNoCheck(_("please wait..."))
+        # self.payto_e.setTextNoCheck(_("please wait..."))
 
     def payment_request_error(self, error):
         self.show_message(error)
@@ -348,45 +345,90 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
             style = ColorScheme.RED.as_stylesheet(True)
         if text is not None:
             w.setStyleSheet(style)
-            w.setReadOnly(True)
         else:
             w.setStyleSheet('')
-            w.setReadOnly(False)
+
+    def lock_fields(self, *,
+            lock_recipient: Optional[bool] = None,
+            lock_amount: Optional[bool] = None,
+            lock_max: Optional[bool] = None,
+            lock_description: Optional[bool] = None
+    ) -> None:
+        self.logger.debug(f'locking fields, r={lock_recipient}, a={lock_amount}, m={lock_max}, d={lock_description}')
+        if lock_recipient is not None:
+            self.payto_e.setFrozen(lock_recipient)
+        if lock_amount is not None:
+            self.amount_e.setFrozen(lock_amount)
+        if lock_max is not None:
+            self.max_button.setEnabled(not lock_max)
+        if lock_description is not None:
+            self.message_e.setFrozen(lock_description)
 
     def update_fields(self):
-        recipient, amount, description, comment, validated = self.payment_identifier.get_fields_for_GUI()
-        if recipient:
-            self.payto_e.setTextNoCheck(recipient)
-        elif self.payment_identifier.multiline_outputs:
-            self.payto_e.handle_multiline(self.payment_identifier.multiline_outputs)
-        if description:
-            self.message_e.setText(description)
-        if amount:
-            self.amount_e.setAmount(amount)
-        for w in [self.comment_e, self.comment_label]:
-            w.setVisible(not bool(comment))
-        self.set_field_style(self.payto_e, recipient or self.payment_identifier.multiline_outputs, validated)
-        self.set_field_style(self.message_e, description, validated)
-        self.set_field_style(self.amount_e, amount, validated)
-        self.set_field_style(self.fiat_send_e, amount, validated)
-
-    def _handle_payment_identifier(self, *, can_use_network: bool = True):
-        is_valid = self.payment_identifier.is_valid()
-        self.save_button.setEnabled(is_valid)
-        self.send_button.setEnabled(is_valid)
-        if not is_valid:
+        pi = self.payto_e.payment_identifier
+
+        if pi.is_multiline():
+            self.lock_fields(lock_recipient=False, lock_amount=True, lock_max=True, lock_description=False)
+            self.set_field_style(self.payto_e, pi.multiline_outputs, False if not pi.is_valid() else None)
+            self.save_button.setEnabled(pi.is_valid())
+            self.send_button.setEnabled(pi.is_valid())
+            if pi.is_valid():
+                self.handle_multiline(pi.multiline_outputs)
+            else:
+                # self.payto_e.setToolTip('\n'.join(list(map(lambda x: f'{x.idx}: {x.line_content}', pi.get_error()))))
+                self.payto_e.setToolTip(pi.get_error())
             return
+
+        if not pi.is_valid():
+            self.lock_fields(lock_recipient=False, lock_amount=False, lock_max=True, lock_description=False)
+            self.save_button.setEnabled(False)
+            self.send_button.setEnabled(False)
+            return
+
+        lock_recipient = pi.type != 'spk'
+        self.lock_fields(lock_recipient=lock_recipient,
+                         lock_amount=pi.is_amount_locked(),
+                         lock_max=pi.is_amount_locked(),
+                         lock_description=False)
+        if lock_recipient:
+            recipient, amount, description, comment, validated = pi.get_fields_for_GUI()
+            if recipient:
+                self.payto_e.setText(recipient)
+            if description:
+                self.message_e.setText(description)
+                self.lock_fields(lock_description=True)
+            if amount:
+                self.amount_e.setAmount(amount)
+            for w in [self.comment_e, self.comment_label]:
+                w.setVisible(bool(comment))
+            self.set_field_style(self.payto_e, recipient or pi.multiline_outputs, validated)
+            self.set_field_style(self.message_e, description, validated)
+            self.set_field_style(self.amount_e, amount, validated)
+            self.set_field_style(self.fiat_send_e, amount, validated)
+
+        self.send_button.setEnabled(bool(self.amount_e.get_amount()) and not pi.has_expired())
+        self.save_button.setEnabled(True)
+
+    def _handle_payment_identifier(self):
+        is_valid = self.payto_e.payment_identifier.is_valid()
+        self.logger.debug(f'handle PI, valid={is_valid}')
+
         self.update_fields()
-        if self.payment_identifier.need_resolve():
+
+        if not is_valid:
+            self.logger.debug(f'PI error: {self.payto_e.payment_identifier.error}')
+            return
+
+        if self.payto_e.payment_identifier.need_resolve():
             self.prepare_for_send_tab_network_lookup()
-            self.payment_identifier.resolve(on_finished=self.resolve_done_signal.emit)
-        # update fiat amount
+            self.payto_e.payment_identifier.resolve(on_finished=self.resolve_done_signal.emit)
+        # update fiat amount (and reset max)
         self.amount_e.textEdited.emit("")
         self.window.show_send_tab()
 
     def on_resolve_done(self, pi):
-        if self.payment_identifier.error:
-            self.show_error(self.payment_identifier.error)
+        if self.payto_e.payment_identifier.error:
+            self.show_error(self.payto_e.payment_identifier.error)
             self.do_clear()
             return
         self.update_fields()
@@ -404,10 +446,10 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
             self.show_error(_('No amount'))
             return
 
-        invoice = self.payment_identifier.get_invoice(amount_sat, self.get_message())
+        invoice = self.payto_e.payment_identifier.get_invoice(amount_sat, self.get_message())
         #except Exception as e:
         if not invoice:
-            self.show_error('error getting invoice' + self.payment_identifier.error)
+            self.show_error('error getting invoice' + self.payto_e.payment_identifier.error)
             return
         if not self.wallet.has_lightning() and not invoice.can_be_paid_onchain():
             self.show_error(_('Lightning is disabled'))
@@ -439,18 +481,17 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         return self.amount_e.get_amount() or 0
 
     def on_finalize_done(self, pi):
-        self.do_clear()
         if pi.error:
             self.show_error(pi.error)
-            self.do_clear()
             return
-        self.update_fields(pi)
+        self.update_fields()
         invoice = pi.get_invoice(self.get_amount(), self.get_message())
         self.pending_invoice = invoice
+        self.logger.debug(f'after finalize invoice: {invoice!r}')
         self.do_pay_invoice(invoice)
 
     def do_pay_or_get_invoice(self):
-        pi = self.payment_identifier
+        pi = self.payto_e.payment_identifier
         if pi.need_finalize():
             self.prepare_for_send_tab_network_lookup()
             pi.finalize(amount_sat=self.get_amount(), comment=self.message_e.text(),
@@ -511,9 +552,9 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         """Returns whether there are errors.
         Also shows error dialog to user if so.
         """
-        error = self.payment_identifier.get_error()
+        error = self.payto_e.payment_identifier.get_error()
         if error:
-            if not self.payment_identifier.is_multiline():
+            if not self.payto_e.payment_identifier.is_multiline():
                 err = error
                 self.show_warning(
                     _("Failed to parse 'Pay to' line") + ":\n" +
@@ -527,13 +568,13 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
                 #               for err in errors]))
             return True
 
-        warning = self.payment_identifier.warning
+        warning = self.payto_e.payment_identifier.warning
         if warning:
             warning += '\n' + _('Do you wish to continue?')
             if not self.question(warning):
                 return True
 
-        if self.payment_identifier.has_expired():
+        if self.payto_e.payment_identifier.has_expired():
             self.show_error(_('Payment request has expired'))
             return True
 
@@ -619,7 +660,7 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
 
         def broadcast_thread():
             # non-GUI thread
-            if self.payment_identifier.has_expired():
+            if self.payto_e.payment_identifier.has_expired():
                 return False, _("Invoice has expired")
             try:
                 self.network.run_from_another_thread(self.network.broadcast_transaction(tx))
@@ -629,9 +670,9 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
                 return False, repr(e)
             # success
             txid = tx.txid()
-            if self.payment_identifier.need_merchant_notify():
+            if self.payto_e.payment_identifier.need_merchant_notify():
                 refund_address = self.wallet.get_receiving_address()
-                self.payment_identifier.notify_merchant(
+                self.payto_e.payment_identifier.notify_merchant(
                     tx=tx,
                     refund_address=refund_address,
                     on_finished=self.notify_merchant_done_signal.emit
@@ -683,10 +724,23 @@ class SendTab(QWidget, MessageBoxMixin, Logger):
         self.window.show_send_tab()
         self.payto_e.do_clear()
         if len(paytos) == 1:
+            self.logger.debug('payto_e setText 1')
             self.payto_e.setText(paytos[0])
             self.amount_e.setFocus()
         else:
             self.payto_e.setFocus()
             text = "\n".join([payto + ", 0" for payto in paytos])
+            self.logger.debug('payto_e setText n')
             self.payto_e.setText(text)
             self.payto_e.setFocus()
+
+    def handle_multiline(self, outputs):
+        total = 0
+        for output in outputs:
+            if parse_max_spend(output.value):
+                self.max_button.setChecked(True) # TODO: remove and let spend_max set this?
+                self.spend_max()
+                return
+            else:
+                total += output.value
+        self.amount_e.setAmount(total if outputs else None)

electrum/gui/qt/util.py

@@ -562,7 +562,10 @@ class GenericInputHandler:
                 new_text = self.text() + data + '\n'
             else:
                 new_text = data
-            setText(new_text)
+                try:
+                    setText(new_text)
+                except Exception as e:
+                    show_error(_('Invalid payment identifier in QR') + ':\n' + repr(e))
 
         from .qrreader import scan_qrcode
         if parent is None:
@@ -599,7 +602,10 @@ class GenericInputHandler:
             new_text = self.text() + data + '\n'
         else:
             new_text = data
-        setText(new_text)
+            try:
+                setText(new_text)
+            except Exception as e:
+                show_error(_('Invalid payment identifier in QR') + ':\n' + repr(e))
 
     def input_file(
             self,
@@ -628,7 +634,10 @@ class GenericInputHandler:
         except BaseException as e:
             show_error(_('Error opening file') + ':\n' + repr(e))
         else:
-            setText(data)
+            try:
+                setText(data)
+            except Exception as e:
+                show_error(_('Invalid payment identifier in file') + ':\n' + repr(e))
 
     def input_paste_from_clipboard(
             self,

electrum/payment_identifier.py

@@ -1,4 +1,5 @@
 import asyncio
+import time
 import urllib
 import re
 from decimal import Decimal, InvalidOperation
@@ -163,13 +164,6 @@ def is_uri(data: str) -> bool:
     return False
 
 
-class PayToLineError(NamedTuple):
-    line_content: str
-    exc: Exception
-    idx: int = 0  # index of line
-    is_multiline: bool = False
-
-
 RE_ALIAS = r'(.*?)\s*\<([0-9A-Za-z]{1,})\>'
 RE_EMAIL = r'\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Z|a-z]{2,7}\b'
 
@@ -210,12 +204,13 @@ class PaymentIdentifier(Logger):
         self.wallet = wallet
         self.contacts = wallet.contacts if wallet is not None else None
         self.config = wallet.config if wallet is not None else None
-        self.text = text
+        self.text = text.strip()
         self._type = None
         self.error = None    # if set, GUI should show error and stop
         self.warning = None  # if set, GUI should ask user if they want to proceed
         # more than one of those may be set
         self.multiline_outputs = None
+        self._is_max = False
         self.bolt11 = None
         self.bip21 = None
         self.spk = None
@@ -234,8 +229,12 @@ class PaymentIdentifier(Logger):
         self.logger.debug(f'PI parsing...')
         self.parse(text)
 
+    @property
+    def type(self):
+        return self._type
+
     def set_state(self, state: 'PaymentIdentifierState'):
-        self.logger.debug(f'PI state -> {state}')
+        self.logger.debug(f'PI state {self._state} -> {state}')
         self._state = state
 
     def need_resolve(self):
@@ -256,6 +255,31 @@ class PaymentIdentifier(Logger):
     def is_multiline(self):
         return bool(self.multiline_outputs)
 
+    def is_multiline_max(self):
+        return self.is_multiline() and self._is_max
+
+    def is_amount_locked(self):
+        if self._type == 'spk':
+            return False
+        elif self._type == 'bip21':
+            return bool(self.bip21.get('amount'))
+        elif self._type == 'bip70':
+            return True  # TODO always given?
+        elif self._type == 'bolt11':
+            lnaddr = lndecode(self.bolt11)
+            return bool(lnaddr.amount)
+        elif self._type == 'lnurl':
+            # amount limits known after resolve, might be specific amount or locked to range
+            if self.need_resolve():
+                self.logger.debug(f'lnurl r')
+                return True
+            if self.need_finalize():
+                self.logger.debug(f'lnurl f {self.lnurl_data.min_sendable_sat}-{self.lnurl_data.max_sendable_sat}')
+                return not (self.lnurl_data.min_sendable_sat < self.lnurl_data.max_sendable_sat)
+            return True
+        elif self._type == 'multiline':
+            return True
+
     def is_error(self) -> bool:
         return self._state >= PaymentIdentifierState.ERROR
 
@@ -281,11 +305,21 @@ class PaymentIdentifier(Logger):
                     self.lnurl = decode_lnurl(invoice_or_lnurl)
                     self.set_state(PaymentIdentifierState.NEED_RESOLVE)
                 except Exception as e:
-                    self.error = "Error parsing Lightning invoice" + f":\n{e}"
+                    self.error = _("Error parsing LNURL") + f":\n{e}"
                     self.set_state(PaymentIdentifierState.INVALID)
                     return
             else:
                 self._type = 'bolt11'
+                try:
+                    lndecode(invoice_or_lnurl)
+                except LnInvoiceException as e:
+                    self.error = _("Error parsing Lightning invoice") + f":\n{e}"
+                    self.set_state(PaymentIdentifierState.INVALID)
+                    return
+                except IncompatibleOrInsaneFeatures as e:
+                    self.error = _("Invoice requires unknown or incompatible Lightning feature") + f":\n{e!r}"
+                    self.set_state(PaymentIdentifierState.INVALID)
+                    return
                 self.bolt11 = invoice_or_lnurl
                 self.set_state(PaymentIdentifierState.AVAILABLE)
         elif text.lower().startswith(BITCOIN_BIP21_URI_SCHEME + ':'):
@@ -295,19 +329,31 @@ class PaymentIdentifier(Logger):
                 self.error = _("Error parsing URI") + f":\n{e}"
                 self.set_state(PaymentIdentifierState.INVALID)
                 return
-            self._type = 'bip21'
             self.bip21 = out
             self.bip70 = out.get('r')
             if self.bip70:
+                self._type = 'bip70'
                 self.set_state(PaymentIdentifierState.NEED_RESOLVE)
             else:
+                self._type = 'bip21'
+                # check optional lightning in bip21, set self.bolt11 if valid
+                bolt11 = out.get('lightning')
+                if bolt11:
+                    try:
+                        lndecode(bolt11)
+                        # if we get here, we have a usable bolt11
+                        self.bolt11 = bolt11
+                    except LnInvoiceException as e:
+                        self.logger.debug(_("Error parsing Lightning invoice") + f":\n{e}")
+                    except IncompatibleOrInsaneFeatures as e:
+                        self.logger.debug(_("Invoice requires unknown or incompatible Lightning feature") + f":\n{e!r}")
                 self.set_state(PaymentIdentifierState.AVAILABLE)
         elif scriptpubkey := self.parse_output(text):
             self._type = 'spk'
             self.spk = scriptpubkey
             self.set_state(PaymentIdentifierState.AVAILABLE)
         elif re.match(RE_EMAIL, text):
-            self._type = 'alias'
+            self._type = 'emaillike'
             self.emaillike = text
             self.set_state(PaymentIdentifierState.NEED_RESOLVE)
         elif self.error is None:
@@ -324,9 +370,10 @@ class PaymentIdentifier(Logger):
     async def _do_resolve(self, *, on_finished=None):
         try:
             if self.emaillike:
+                # TODO: parallel lookup?
                 data = await self.resolve_openalias()
                 if data:
-                    self.openalias_data = data # needed?
+                    self.openalias_data = data
                     self.logger.debug(f'OA: {data!r}')
                     name = data.get('name')
                     address = data.get('address')
@@ -335,8 +382,14 @@ class PaymentIdentifier(Logger):
                         self.warning = _(
                             'WARNING: the alias "{}" could not be validated via an additional '
                             'security check, DNSSEC, and thus may not be correct.').format(self.emaillike)
-                    # this will set self.spk and update state
-                    self.parse(address)
+                    try:
+                        scriptpubkey = self.parse_output(address)
+                        self._type = 'openalias'
+                        self.spk = scriptpubkey
+                        self.set_state(PaymentIdentifierState.AVAILABLE)
+                    except Exception as e:
+                        self.error = str(e)
+                        self.set_state(PaymentIdentifierState.NOT_FOUND)
                 else:
                     lnurl = lightning_address_to_url(self.emaillike)
                     try:
@@ -356,6 +409,7 @@ class PaymentIdentifier(Logger):
                 data = await request_lnurl(self.lnurl)
                 self.lnurl_data = data
                 self.set_state(PaymentIdentifierState.LNURLP_FINALIZE)
+                self.logger.debug(f'LNURL data: {data!r}')
             else:
                 self.set_state(PaymentIdentifierState.ERROR)
                 return
@@ -458,23 +512,22 @@ class PaymentIdentifier(Logger):
         lines = [i for i in lines if i]
         is_multiline = len(lines) > 1
         outputs = []  # type: List[PartialTxOutput]
-        errors = []
+        errors = ''
         total = 0
-        is_max = False
+        self._is_max = False
         for i, line in enumerate(lines):
             try:
                 output = self.parse_address_and_amount(line)
                 outputs.append(output)
                 if parse_max_spend(output.value):
-                    is_max = True
+                    self._is_max = True
                 else:
                     total += output.value
             except Exception as e:
-                errors.append(PayToLineError(
-                    idx=i, line_content=line.strip(), exc=e, is_multiline=True))
+                errors = f'{errors}line #{i}: {str(e)}\n'
                 continue
         if is_multiline and errors:
-            self.error = str(errors) if errors else None
+            self.error = errors.strip() if errors else None
         self.logger.debug(f'multiline: {outputs!r}, {self.error}')
         return outputs
 
@@ -494,15 +547,14 @@ class PaymentIdentifier(Logger):
             address = self.parse_address(x)
             return bytes.fromhex(bitcoin.address_to_script(address))
         except Exception as e:
-            error = PayToLineError(idx=0, line_content=x, exc=e, is_multiline=False)
+            pass
         try:
             script = self.parse_script(x)
             return bytes.fromhex(script)
         except Exception as e:
-            #error = PayToLineError(idx=0, line_content=x, exc=e, is_multiline=False)
             pass
-        #raise Exception("Invalid address or script.")
-        #self.errors.append(error)
+
+        raise Exception("Invalid address or script.")
 
     def parse_script(self, x):
         script = ''
@@ -535,12 +587,11 @@ class PaymentIdentifier(Logger):
         return address
 
     def get_fields_for_GUI(self):
-        """ sets self.error as side effect"""
         recipient = None
         amount = None
         description = None
         validated = None
-        comment = "no comment"
+        comment = None
 
         if self.emaillike and self.openalias_data:
             address = self.openalias_data.get('address')
@@ -550,21 +601,17 @@ class PaymentIdentifier(Logger):
             if not validated:
                 self.warning = _('WARNING: the alias "{}" could not be validated via an additional '
                                  'security check, DNSSEC, and thus may not be correct.').format(self.emaillike)
-            #self.payto_e.set_openalias(key=pi.openalias, data=oa_data)
-            #self.window.contact_list.update()
 
-        elif self.bolt11:
-            recipient, amount, description = self.get_bolt11_fields(self.bolt11)
+        elif self.bolt11 and self.wallet.has_lightning():
+            recipient, amount, description = self._get_bolt11_fields(self.bolt11)
 
         elif self.lnurl and self.lnurl_data:
             domain = urllib.parse.urlparse(self.lnurl).netloc
-            #recipient = "invoice from lnurl"
             recipient = f"{self.lnurl_data.metadata_plaintext} <{domain}>"
-            #amount = self.lnurl_data.min_sendable_sat
-            amount = None
-            description = None
+            amount = self.lnurl_data.min_sendable_sat if self.lnurl_data.min_sendable_sat else None
+            description = self.lnurl_data.metadata_plaintext
             if self.lnurl_data.comment_allowed:
-                comment = None
+                comment = self.lnurl_data.comment_allowed
 
         elif self.bip70 and self.bip70_data:
             pr = self.bip70_data
@@ -575,8 +622,6 @@ class PaymentIdentifier(Logger):
             amount = pr.get_amount()
             description = pr.get_memo()
             validated = not pr.has_expired()
-            #self.set_onchain(True)
-            #self.max_button.setEnabled(False)
             # note: allow saving bip70 reqs, as we save them anyway when paying them
             #for btn in [self.send_button, self.clear_button, self.save_button]:
             #    btn.setEnabled(True)
@@ -584,8 +629,7 @@ class PaymentIdentifier(Logger):
             #self.amount_e.textEdited.emit("")
 
         elif self.spk:
-            recipient = self.text
-            amount = None
+            pass
 
         elif self.multiline_outputs:
             pass
@@ -598,26 +642,12 @@ class PaymentIdentifier(Logger):
             # use label as description (not BIP21 compliant)
             if label and not description:
                 description = label
-            lightning = self.bip21.get('lightning')
-            if lightning and self.wallet.has_lightning():
-                # maybe set self.bolt11?
-                recipient, amount, description = self.get_bolt11_fields(lightning)
-                if not amount:
-                    amount_required = True
-                # todo: merge logic
 
         return recipient, amount, description, comment, validated
 
-    def get_bolt11_fields(self, bolt11_invoice):
+    def _get_bolt11_fields(self, bolt11_invoice):
         """Parse ln invoice, and prepare the send tab for it."""
-        try:
-            lnaddr = lndecode(bolt11_invoice)
-        except LnInvoiceException as e:
-            self.show_error(_("Error parsing Lightning invoice") + f":\n{e}")
-            return
-        except IncompatibleOrInsaneFeatures as e:
-            self.show_error(_("Invoice requires unknown or incompatible Lightning feature") + f":\n{e!r}")
-            return
+        lnaddr = lndecode(bolt11_invoice) #
         pubkey = lnaddr.pubkey.serialize().hex()
         for k, v in lnaddr.tags:
             if k == 'd':
@@ -628,15 +658,17 @@ class PaymentIdentifier(Logger):
         amount = lnaddr.get_amount_sat()
         return pubkey, amount, description
 
+    # TODO: rename to resolve_emaillike to disambiguate
     async def resolve_openalias(self) -> Optional[dict]:
         key = self.emaillike
-        if not (('.' in key) and ('<' not in key) and (' ' not in key)):
-            return None
+        # TODO: below check needed? we already matched RE_EMAIL
+        # if not (('.' in key) and ('<' not in key) and (' ' not in key)):
+        #     return None
         parts = key.split(sep=',')  # assuming single line
         if parts and len(parts) > 0 and bitcoin.is_address(parts[0]):
             return None
         try:
-            data = self.contacts.resolve(key)
+            data = self.contacts.resolve(key) # TODO: don't use contacts as delegate to resolve openalias, separate.
             return data
         except AliasNotFoundException as e:
             self.logger.info(f'OpenAlias not found: {repr(e)}')
@@ -648,6 +680,12 @@ class PaymentIdentifier(Logger):
     def has_expired(self):
         if self.bip70:
             return self.bip70_data.has_expired()
+        elif self.bolt11:
+            lnaddr = lndecode(self.bolt11)
+            return lnaddr.is_expired()
+        elif self.bip21:
+            expires = self.bip21.get('exp') + self.bip21.get('time') if self.bip21.get('exp') else 0
+            return bool(expires) and expires < time.time()
         return False
 
     def get_invoice(self, amount_sat, message):