#!/usr/bin/env python
#
# Electrum - lightweight Bitcoin client
# Copyright (C) 2012 thomasv@gitorious
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
import sys
import time
import threading
import os
import traceback
import json
import shutil
import weakref
import csv
from decimal import Decimal
import base64
from functools import partial
import queue
import asyncio
from typing import Optional, TYPE_CHECKING, Sequence, List, Union

from PyQt5.QtGui import QPixmap, QKeySequence, QIcon, QCursor, QFont
from PyQt5.QtCore import Qt, QRect, QStringListModel, QSize, pyqtSignal
from PyQt5.QtWidgets import (QMessageBox, QComboBox, QSystemTrayIcon, QTabWidget,
                             QMenuBar, QFileDialog, QCheckBox, QLabel,
                             QVBoxLayout, QGridLayout, QLineEdit,
                             QHBoxLayout, QPushButton, QScrollArea, QTextEdit,
                             QShortcut, QMainWindow, QCompleter, QInputDialog,
                             QWidget, QSizePolicy, QStatusBar, QToolTip, QDialog,
                             QMenu, QAction, QStackedWidget)

import electrum
from electrum import (keystore, ecc, constants, util, bitcoin, commands,
                      paymentrequest, lnutil)
from electrum.bitcoin import COIN, is_address
from electrum.plugin import run_hook, BasePlugin
from electrum.i18n import _
from electrum.merkle import MerkleVerificationFailure
from electrum.names import format_name_identifier, get_wallet_name_count, name_new_mature_in
from electrum.util import (format_time,
                           UserCancelled, profiler,
                           bh2u, bfh, InvalidPassword,
                           UserFacingException,
                           get_new_wallet_name, send_exception_to_crash_reporter,
                           InvalidBitcoinURI, maybe_extract_bolt11_invoice, NotEnoughFunds,
                           NoDynamicFeeEstimates, MultipleSpendMaxTxOutputs,
                           AddTransactionException)
from electrum.invoices import PR_TYPE_ONCHAIN, PR_TYPE_LN, PR_DEFAULT_EXPIRATION_WHEN_CREATING, Invoice
from electrum.invoices import PR_PAID, PR_FAILED, pr_expiration_values, LNInvoice, OnchainInvoice
from electrum.transaction import (Transaction, PartialTxInput,
                                  PartialTransaction, PartialTxOutput)
from electrum.wallet import (Multisig_Wallet, CannotBumpFee, Abstract_Wallet,
                             sweep_preparations, InternalAddressCorruption,
                             CannotDoubleSpendTx)
from electrum.version import ELECTRUM_VERSION
from electrum.network import Network, TxBroadcastError, BestEffortRequestFailed, UntrustedServerReturnedError
from electrum.exchange_rate import FxThread
from electrum.simple_config import SimpleConfig
from electrum.logging import Logger
from electrum.lnutil import ln_dummy_address, extract_nodeid, ConnStringFormatError
from electrum.lnaddr import lndecode, LnDecodeException

from .exception_window import Exception_Hook
from .amountedit import AmountEdit, BTCAmountEdit, FreezableLineEdit, FeerateEdit
from .configure_name_dialog import show_configure_name
from .trade_name_dialog import show_trade_name
from .qrcodewidget import QRCodeWidget, QRDialog
from .qrtextedit import ShowQRTextEdit, ScanQRTextEdit
from .transaction_dialog import show_transaction
from .fee_slider import FeeSlider, FeeComboBox
from .util import (read_QIcon, ColorScheme, text_dialog, icon_path, WaitingDialog,
                   WindowModalDialog, ChoicesLayout, HelpLabel, Buttons,
                   OkButton, InfoButton, WWLabel, TaskThread, CancelButton,
                   CloseButton, HelpButton, MessageBoxMixin, EnterButton,
                   import_meta_gui, export_meta_gui,
                   filename_field, address_field, char_width_in_lineedit, webopen,
                   TRANSACTION_FILE_EXTENSION_FILTER_ANY, MONOSPACE_FONT)
from .util import ButtonsTextEdit, ButtonsLineEdit
from .installwizard import WIF_HELP_TEXT
from .history_list import HistoryList, HistoryModel
from .update_checker import UpdateCheck, UpdateCheckThread
from .channels_list import ChannelsList
from .confirm_tx_dialog import ConfirmTxDialog
from .transaction_dialog import PreviewTxDialog

from .forms.managenamespage import Ui_ManageNamesPage
from .forms.buynamespage import Ui_BuyNamesPage

if TYPE_CHECKING:
    from . import ElectrumGui


LN_NUM_PAYMENT_ATTEMPTS = 10

class StatusBarButton(QPushButton):
    def __init__(self, icon, tooltip, func):
        QPushButton.__init__(self, icon, '')
        self.setToolTip(tooltip)
        self.setFlat(True)
        self.setMaximumWidth(25)
        self.clicked.connect(self.onPress)
        self.func = func
        self.setIconSize(QSize(25,25))
        self.setCursor(QCursor(Qt.PointingHandCursor))

    def onPress(self, checked=False):
        '''Drops the unwanted PyQt5 "checked" argument'''
        self.func()

    def keyPressEvent(self, e):
        if e.key() in [ Qt.Key_Return, Qt.Key_Enter ]:
            self.func()


def protected(func):
    '''Password request wrapper.  The password is passed to the function
        as the 'password' named argument.  "None" indicates either an
        unencrypted wallet, or the user cancelled the password request.
        An empty input is passed as the empty string.'''
    def request_password(self, *args, **kwargs):
        parent = self.top_level_window()
        password = None
        while self.wallet.has_keystore_encryption():
            password = self.password_dialog(parent=parent)
            if password is None:
                # User cancelled password input
                return
            try:
                self.wallet.check_password(password)
                break
            except Exception as e:
                self.show_error(str(e), parent=parent)
                continue

        kwargs['password'] = password
        return func(self, *args, **kwargs)
    return request_password


class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):

    payment_request_ok_signal = pyqtSignal()
    payment_request_error_signal = pyqtSignal()
    network_signal = pyqtSignal(str, object)
    #ln_payment_attempt_signal = pyqtSignal(str)
    alias_received_signal = pyqtSignal()
    computing_privkeys_signal = pyqtSignal()
    show_privkeys_signal = pyqtSignal()
    show_error_signal = pyqtSignal(str)

    payment_request: Optional[paymentrequest.PaymentRequest]

    def __init__(self, gui_object: 'ElectrumGui', wallet: Abstract_Wallet):
        QMainWindow.__init__(self)

        self.gui_object = gui_object
        self.config = config = gui_object.config  # type: SimpleConfig
        self.gui_thread = gui_object.gui_thread
        assert wallet, "no wallet"
        self.wallet = wallet
        if wallet.has_lightning():
            self.wallet.config.set_key('show_channels_tab', True)

        self.setup_exception_hook()

        self.network = gui_object.daemon.network  # type: Network
        self.fx = gui_object.daemon.fx  # type: FxThread
        self.contacts = wallet.contacts
        self.tray = gui_object.tray
        self.app = gui_object.app
        self.cleaned_up = False
        self.payment_request = None  # type: Optional[paymentrequest.PaymentRequest]
        self.payto_URI = None
        self.checking_accounts = False
        self.qr_window = None
        self.pluginsdialog = None
        self.showing_cert_mismatch_error = False
        self.tl_windows = []
        Logger.__init__(self)

        self.tx_notification_queue = queue.Queue()
        self.tx_notification_last_time = 0

        self.create_status_bar()
        self.need_update = threading.Event()

        self.completions = QStringListModel()

        coincontrol_sb = self.create_coincontrol_statusbar()

        self.tabs = tabs = QTabWidget(self)
        self.send_tab = self.create_send_tab()
        self.receive_tab = self.create_receive_tab()
        self.addresses_tab = self.create_addresses_tab()
        self.utxo_tab = self.create_utxo_tab()
        self.console_tab = self.create_console_tab()
        self.contacts_tab = self.create_contacts_tab()
        self.channels_tab = self.create_channels_tab()
        self.buy_names_tab = self.create_buy_names_tab()
        self.names_tab = self.create_names_tab()
        tabs.addTab(self.create_history_tab(), read_QIcon("tab_history.png"), _('History'))
        tabs.addTab(self.send_tab, read_QIcon("tab_send.png"), _('Send'))
        tabs.addTab(self.receive_tab, read_QIcon("tab_receive.png"), _('Receive'))
        tabs.addTab(self.buy_names_tab, read_QIcon("namecoin-logo.png"), _('Buy Names'))
        tabs.addTab(self.names_tab, read_QIcon("namecoin-logo.png"), _('Manage Names'))

        def add_optional_tab(tabs, tab, icon, description, name):
            tab.tab_icon = icon
            tab.tab_description = description
            tab.tab_pos = len(tabs)
            tab.tab_name = name
            if self.config.get('show_{}_tab'.format(name), False):
                tabs.addTab(tab, icon, description.replace("&", ""))

        add_optional_tab(tabs, self.addresses_tab, read_QIcon("tab_addresses.png"), _("&Addresses"), "addresses")
        add_optional_tab(tabs, self.channels_tab, read_QIcon("lightning.png"), _("Channels"), "channels")
        add_optional_tab(tabs, self.utxo_tab, read_QIcon("tab_coins.png"), _("Co&ins"), "utxo")
        add_optional_tab(tabs, self.contacts_tab, read_QIcon("tab_contacts.png"), _("Con&tacts"), "contacts")
        add_optional_tab(tabs, self.console_tab, read_QIcon("tab_console.png"), _("Con&sole"), "console")

        tabs.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)

        central_widget = QWidget()
        vbox = QVBoxLayout(central_widget)
        vbox.setContentsMargins(0, 0, 0, 0)
        vbox.addWidget(tabs)
        vbox.addWidget(coincontrol_sb)

        self.setCentralWidget(central_widget)

        if self.config.get("is_maximized"):
            self.showMaximized()

        self.setWindowIcon(read_QIcon("electrum_nmc.png"))
        self.init_menubar()

        wrtabs = weakref.proxy(tabs)
        QShortcut(QKeySequence("Ctrl+W"), self, self.close)
        QShortcut(QKeySequence("Ctrl+Q"), self, self.close)
        QShortcut(QKeySequence("Ctrl+R"), self, self.update_wallet)
        QShortcut(QKeySequence("F5"), self, self.update_wallet)
        QShortcut(QKeySequence("Ctrl+PgUp"), self, lambda: wrtabs.setCurrentIndex((wrtabs.currentIndex() - 1)%wrtabs.count()))
        QShortcut(QKeySequence("Ctrl+PgDown"), self, lambda: wrtabs.setCurrentIndex((wrtabs.currentIndex() + 1)%wrtabs.count()))

        for i in range(wrtabs.count()):
            QShortcut(QKeySequence("Alt+" + str(i + 1)), self, lambda i=i: wrtabs.setCurrentIndex(i))

        self.payment_request_ok_signal.connect(self.payment_request_ok)
        self.payment_request_error_signal.connect(self.payment_request_error)
        self.show_error_signal.connect(self.show_error)
        self.history_list.setFocus(True)

        # network callbacks
        if self.network:
            self.network_signal.connect(self.on_network_qt)
            interests = ['wallet_updated', 'network_updated', 'blockchain_updated',
                         'new_transaction', 'status',
                         'banner', 'verified', 'fee', 'fee_histogram', 'on_quotes',
                         'on_history', 'channel', 'channels_updated',
                         'payment_failed', 'payment_succeeded',
                         'invoice_status', 'request_status', 'ln_gossip_sync_progress',
                         'cert_mismatch', 'gossip_db_loaded']
            # To avoid leaking references to "self" that prevent the
            # window from being GC-ed when closed, callbacks should be
            # methods of this class only, and specifically not be
            # partials, lambdas or methods of subobjects.  Hence...
            util.register_callback(self.on_network, interests)
            # set initial message
            self.console.showMessage(self.network.banner)

        # update fee slider in case we missed the callback
        #self.fee_slider.update()
        self.load_wallet(wallet)
        gui_object.timer.timeout.connect(self.timer_actions)
        self.fetch_alias()

        # If the option hasn't been set yet
        if config.get('check_updates') is None:
            choice = self.question(title="Electrum-NMC - " + _("Enable update check"),
                                   msg=_("For security reasons we advise that you always use the latest version of Electrum-NMC.") + " " +
                                       _("Would you like to be notified when there is a newer version of Electrum-NMC available?"))
            config.set_key('check_updates', bool(choice), save=True)

        if config.get('check_updates', False):
            # The references to both the thread and the window need to be stored somewhere
            # to prevent GC from getting in our way.
            def on_version_received(v):
                if UpdateCheck.is_newer(v):
                    self.update_check_button.setText(_("Update to Electrum-NMC {} is available").format(v))
                    self.update_check_button.clicked.connect(lambda: self.show_update_check(v))
                    self.update_check_button.show()
            self._update_check_thread = UpdateCheckThread()
            self._update_check_thread.checked.connect(on_version_received)
            self._update_check_thread.start()

    def setup_exception_hook(self):
        Exception_Hook.maybe_setup(config=self.config,
                                   wallet=self.wallet)

    def run_coroutine_from_thread(self, coro, on_result=None):
        def task():
            try:
                f = asyncio.run_coroutine_threadsafe(coro, self.network.asyncio_loop)
                r = f.result()
                if on_result:
                    on_result(r)
            except Exception as e:
                self.logger.exception("exception in coro scheduled via window.wallet")
                self.show_error_signal.emit(str(e))
        self.wallet.thread.add(task)

    def on_fx_history(self):
        self.history_model.refresh('fx_history')
        self.address_list.update()

    def on_fx_quotes(self):
        self.update_status()
        # Refresh edits with the new rate
        edit = self.fiat_send_e if self.fiat_send_e.is_last_edited else self.amount_e
        edit.textEdited.emit(edit.text())
        edit = self.fiat_receive_e if self.fiat_receive_e.is_last_edited else self.receive_amount_e
        edit.textEdited.emit(edit.text())
        # History tab needs updating if it used spot
        if self.fx.history_used_spot:
            self.history_model.refresh('fx_quotes')
        self.address_list.update()

    def toggle_tab(self, tab):
        show = not self.config.get('show_{}_tab'.format(tab.tab_name), False)
        self.config.set_key('show_{}_tab'.format(tab.tab_name), show)
        item_text = (_("Hide {}") if show else _("Show {}")).format(tab.tab_description)
        tab.menu_action.setText(item_text)
        if show:
            # Find out where to place the tab
            index = len(self.tabs)
            for i in range(len(self.tabs)):
                try:
                    if tab.tab_pos < self.tabs.widget(i).tab_pos:
                        index = i
                        break
                except AttributeError:
                    pass
            self.tabs.insertTab(index, tab, tab.tab_icon, tab.tab_description.replace("&", ""))
        else:
            i = self.tabs.indexOf(tab)
            self.tabs.removeTab(i)

    def push_top_level_window(self, window):
        '''Used for e.g. tx dialog box to ensure new dialogs are appropriately
        parented.  This used to be done by explicitly providing the parent
        window, but that isn't something hardware wallet prompts know.'''
        self.tl_windows.append(window)

    def pop_top_level_window(self, window):
        self.tl_windows.remove(window)

    def top_level_window(self, test_func=None):
        '''Do the right thing in the presence of tx dialog windows'''
        override = self.tl_windows[-1] if self.tl_windows else None
        if override and test_func and not test_func(override):
            override = None  # only override if ok for test_func
        return self.top_level_window_recurse(override, test_func)

    def diagnostic_name(self):
        #return '{}:{}'.format(self.__class__.__name__, self.wallet.diagnostic_name())
        return self.wallet.diagnostic_name()

    def is_hidden(self):
        return self.isMinimized() or self.isHidden()

    def show_or_hide(self):
        if self.is_hidden():
            self.bring_to_top()
        else:
            self.hide()

    def bring_to_top(self):
        self.show()
        self.raise_()

    def on_error(self, exc_info):
        e = exc_info[1]
        if isinstance(e, UserCancelled):
            pass
        elif isinstance(e, UserFacingException):
            self.show_error(str(e))
        else:
            # TODO would be nice if we just sent these to the crash reporter...
            #      anything we don't want to send there, we should explicitly catch
            # send_exception_to_crash_reporter(e)
            try:
                self.logger.error("on_error", exc_info=exc_info)
            except OSError:
                pass  # see #4418
            self.show_error(repr(e))

    def on_network(self, event, *args):
        # Handle in GUI thread
        self.network_signal.emit(event, args)

    def on_network_qt(self, event, args=None):
        # Handle a network message in the GUI thread
        # note: all windows get events from all wallets!
        if event == 'wallet_updated':
            wallet = args[0]
            if wallet == self.wallet:
                self.need_update.set()
        elif event == 'network_updated':
            self.gui_object.network_updated_signal_obj.network_updated_signal \
                .emit(event, args)
            self.network_signal.emit('status', None)
        elif event == 'blockchain_updated':
            # to update number of confirmations in history
            self.need_update.set()
            self.update_queued_transactions()
        elif event == 'new_transaction':
            wallet, tx = args
            if wallet == self.wallet:
                self.tx_notification_queue.put(tx)
        elif event == 'on_quotes':
            self.on_fx_quotes()
        elif event == 'on_history':
            self.on_fx_history()
        elif event == 'gossip_db_loaded':
            self.channels_list.gossip_db_loaded.emit(*args)
        elif event == 'channels_updated':
            wallet = args[0]
            if wallet == self.wallet:
                self.channels_list.update_rows.emit(*args)
        elif event == 'channel':
            wallet = args[0]
            if wallet == self.wallet:
                self.channels_list.update_single_row.emit(*args)
                self.update_status()
        elif event == 'request_status':
            self.on_request_status(*args)
        elif event == 'invoice_status':
            self.on_invoice_status(*args)
        elif event == 'payment_succeeded':
            wallet = args[0]
            if wallet == self.wallet:
                self.on_payment_succeeded(*args)
        elif event == 'payment_failed':
            wallet = args[0]
            if wallet == self.wallet:
                self.on_payment_failed(*args)
        elif event == 'status':
            self.update_status()
        elif event == 'banner':
            self.console.showMessage(args[0])
        elif event == 'verified':
            wallet, tx_hash, tx_mined_status = args
            if wallet == self.wallet:
                self.history_model.update_tx_mined_status(tx_hash, tx_mined_status)
        elif event == 'fee':
            pass
        elif event == 'fee_histogram':
            self.history_model.on_fee_histogram()
        elif event == 'ln_gossip_sync_progress':
            self.update_lightning_icon()
        elif event == 'cert_mismatch':
            self.show_cert_mismatch_error()
        else:
            self.logger.info(f"unexpected network event: {event} {args}")

    def fetch_alias(self):
        self.alias_info = None
        alias = self.config.get('alias')
        if alias:
            alias = str(alias)
            def f():
                self.alias_info = self.contacts.resolve_openalias(alias)
                self.alias_received_signal.emit()
            t = threading.Thread(target=f)
            t.setDaemon(True)
            t.start()

    def close_wallet(self):
        if self.wallet:
            self.logger.info(f'close_wallet {self.wallet.storage.path}')
            self.wallet.thread = None
        run_hook('close_wallet', self.wallet)

    @profiler
    def load_wallet(self, wallet: Abstract_Wallet):
        wallet.thread = TaskThread(self, self.on_error)
        self.update_recently_visited(wallet.storage.path)
        if wallet.has_lightning():
            util.trigger_callback('channels_updated', wallet)
        self.need_update.set()
        # Once GUI has been initialized check if we want to announce something since the callback has been called before the GUI was initialized
        # update menus
        self.seed_menu.setEnabled(self.wallet.has_seed())
        self.update_lock_icon()
        self.update_buttons_on_seed()
        self.update_console()
        self.clear_receive_tab()
        self.request_list.update()
        self.channels_list.update()
        self.tabs.show()
        self.init_geometry()
        if self.config.get('hide_gui') and self.gui_object.tray.isVisible():
            self.hide()
        else:
            self.show()
        self.watching_only_changed()
        run_hook('load_wallet', wallet, self)
        try:
            wallet.try_detecting_internal_addresses_corruption()
        except InternalAddressCorruption as e:
            self.show_error(str(e))
            send_exception_to_crash_reporter(e)

    def init_geometry(self):
        winpos = self.wallet.db.get("winpos-qt")
        try:
            screen = self.app.desktop().screenGeometry()
            assert screen.contains(QRect(*winpos))
            self.setGeometry(*winpos)
        except:
            self.logger.info("using default geometry")
            self.setGeometry(100, 100, 840, 400)

    def watching_only_changed(self):
        name = "Electrum-NMC Testnet" if constants.net.TESTNET else "Electrum-NMC"
        title = '%s %s  -  %s' % (name, ELECTRUM_VERSION,
                                        self.wallet.basename())
        extra = [self.wallet.db.get('wallet_type', '?')]
        if self.wallet.is_watching_only():
            extra.append(_('watching only'))
        title += '  [%s]'% ', '.join(extra)
        self.setWindowTitle(title)
        self.password_menu.setEnabled(self.wallet.may_have_password())
        self.import_privkey_menu.setVisible(self.wallet.can_import_privkey())
        self.import_address_menu.setVisible(self.wallet.can_import_address())
        self.export_menu.setEnabled(self.wallet.can_export())

    def warn_if_watching_only(self):
        if self.wallet.is_watching_only():
            msg = ' '.join([
                _("This wallet is watching-only."),
                _("This means you will not be able to spend Namecoins or update names with it."),
                _("Make sure you own the seed phrase or the private keys, before you request Namecoins or names to be sent to this wallet.")
            ])
            self.show_warning(msg, title=_('Watch-only wallet'))

    def warn_if_testnet(self):
        if not constants.net.TESTNET:
            return
        # user might have opted out already
        if self.config.get('dont_show_testnet_warning', False):
            return
        # only show once per process lifecycle
        if getattr(self.gui_object, '_warned_testnet', False):
            return
        self.gui_object._warned_testnet = True
        msg = ''.join([
            _("You are in testnet mode."), ' ',
            _("Testnet coins and names are worthless."), '\n',
            _("Testnet is separate from the main Namecoin network. It is used for testing.")
        ])
        cb = QCheckBox(_("Don't show this again."))
        cb_checked = False
        def on_cb(x):
            nonlocal cb_checked
            cb_checked = x == Qt.Checked
        cb.stateChanged.connect(on_cb)
        self.show_warning(msg, title=_('Testnet'), checkbox=cb)
        if cb_checked:
            self.config.set_key('dont_show_testnet_warning', True)

    def open_wallet(self):
        try:
            wallet_folder = self.get_wallet_folder()
        except FileNotFoundError as e:
            self.show_error(str(e))
            return
        filename, __ = QFileDialog.getOpenFileName(self, "Select your wallet file", wallet_folder)
        if not filename:
            return
        self.gui_object.new_window(filename)

    def select_backup_dir(self, b):
        name = self.config.get('backup_dir', '')
        dirname = QFileDialog.getExistingDirectory(self, "Select your wallet backup directory", name)
        if dirname:
            self.config.set_key('backup_dir', dirname)
            self.backup_dir_e.setText(dirname)

    def backup_wallet(self):
        d = WindowModalDialog(self, _("File Backup"))
        vbox = QVBoxLayout(d)
        grid = QGridLayout()
        backup_help = ""
        backup_dir = self.config.get('backup_dir')
        backup_dir_label = HelpLabel(_('Backup directory') + ':', backup_help)
        msg = _('Please select a backup directory')
        if self.wallet.has_lightning() and self.wallet.lnworker.channels:
            msg += '\n\n' + ' '.join([
                _("Note that lightning channels will be converted to channel backups."),
                _("You cannot use channel backups to perform lightning payments."),
                _("Channel backups can only be used to request your channels to be closed.")
            ])
        self.backup_dir_e = QPushButton(backup_dir)
        self.backup_dir_e.clicked.connect(self.select_backup_dir)
        grid.addWidget(backup_dir_label, 1, 0)
        grid.addWidget(self.backup_dir_e, 1, 1)
        vbox.addLayout(grid)
        vbox.addWidget(WWLabel(msg))
        vbox.addLayout(Buttons(CancelButton(d), OkButton(d)))
        if not d.exec_():
            return
        try:
            new_path = self.wallet.save_backup()
        except BaseException as reason:
            self.show_critical(_("Electrum-NMC was unable to copy your wallet file to the specified location.") + "\n" + str(reason), title=_("Unable to create backup"))
            return
        if new_path:
            msg = _("A copy of your wallet file was created in")+" '%s'" % str(new_path)
            self.show_message(msg, title=_("Wallet backup created"))
        else:
            self.show_message(_("You need to configure a backup directory in your preferences"), title=_("Backup not created"))

    def update_recently_visited(self, filename):
        recent = self.config.get('recently_open', [])
        try:
            sorted(recent)
        except:
            recent = []
        if filename in recent:
            recent.remove(filename)
        recent.insert(0, filename)
        recent = [path for path in recent if os.path.exists(path)]
        recent = recent[:5]
        self.config.set_key('recently_open', recent)
        self.recently_visited_menu.clear()
        for i, k in enumerate(sorted(recent)):
            b = os.path.basename(k)
            def loader(k):
                return lambda: self.gui_object.new_window(k)
            self.recently_visited_menu.addAction(b, loader(k)).setShortcut(QKeySequence("Ctrl+%d"%(i+1)))
        self.recently_visited_menu.setEnabled(len(recent))

    def get_wallet_folder(self):
        return os.path.dirname(os.path.abspath(self.wallet.storage.path))

    def new_wallet(self):
        try:
            wallet_folder = self.get_wallet_folder()
        except FileNotFoundError as e:
            self.show_error(str(e))
            return
        filename = get_new_wallet_name(wallet_folder)
        full_path = os.path.join(wallet_folder, filename)
        self.gui_object.start_new_window(full_path, None)

    def init_menubar(self):
        menubar = QMenuBar()

        file_menu = menubar.addMenu(_("&File"))
        self.recently_visited_menu = file_menu.addMenu(_("&Recently open"))
        file_menu.addAction(_("&Open"), self.open_wallet).setShortcut(QKeySequence.Open)
        file_menu.addAction(_("&New/Restore"), self.new_wallet).setShortcut(QKeySequence.New)
        file_menu.addAction(_("&Save backup"), self.backup_wallet).setShortcut(QKeySequence.SaveAs)
        file_menu.addAction(_("Delete"), self.remove_wallet)
        file_menu.addSeparator()
        file_menu.addAction(_("&Quit"), self.close)

        wallet_menu = menubar.addMenu(_("&Wallet"))
        wallet_menu.addAction(_("&Information"), self.show_wallet_info)
        wallet_menu.addSeparator()
        self.password_menu = wallet_menu.addAction(_("&Password"), self.change_password_dialog)
        self.seed_menu = wallet_menu.addAction(_("&Seed"), self.show_seed_dialog)
        self.private_keys_menu = wallet_menu.addMenu(_("&Private keys"))
        self.private_keys_menu.addAction(_("&Sweep"), self.sweep_key_dialog)
        self.import_privkey_menu = self.private_keys_menu.addAction(_("&Import"), self.do_import_privkey)
        self.export_menu = self.private_keys_menu.addAction(_("&Export"), self.export_privkeys_dialog)
        self.import_address_menu = wallet_menu.addAction(_("Import addresses"), self.import_addresses)
        wallet_menu.addSeparator()

        addresses_menu = wallet_menu.addMenu(_("&Addresses"))
        addresses_menu.addAction(_("&Filter"), lambda: self.address_list.toggle_toolbar(self.config))
        labels_menu = wallet_menu.addMenu(_("&Labels"))
        labels_menu.addAction(_("&Import"), self.do_import_labels)
        labels_menu.addAction(_("&Export"), self.do_export_labels)
        history_menu = wallet_menu.addMenu(_("&History"))
        history_menu.addAction(_("&Filter"), lambda: self.history_list.toggle_toolbar(self.config))
        history_menu.addAction(_("&Summary"), self.history_list.show_summary)
        history_menu.addAction(_("&Plot"), self.history_list.plot_history_dialog)
        history_menu.addAction(_("&Export"), self.history_list.export_history_dialog)
        contacts_menu = wallet_menu.addMenu(_("Contacts"))
        contacts_menu.addAction(_("&New"), self.new_contact_dialog)
        contacts_menu.addAction(_("Import"), lambda: self.import_contacts())
        contacts_menu.addAction(_("Export"), lambda: self.export_contacts())
        invoices_menu = wallet_menu.addMenu(_("Invoices"))
        invoices_menu.addAction(_("Import"), lambda: self.import_invoices())
        invoices_menu.addAction(_("Export"), lambda: self.export_invoices())
        requests_menu = wallet_menu.addMenu(_("Requests"))
        requests_menu.addAction(_("Import"), lambda: self.import_requests())
        requests_menu.addAction(_("Export"), lambda: self.export_requests())

        wallet_menu.addSeparator()
        wallet_menu.addAction(_("Find"), self.toggle_search).setShortcut(QKeySequence("Ctrl+F"))

        def add_toggle_action(view_menu, tab):
            is_shown = self.config.get('show_{}_tab'.format(tab.tab_name), False)
            item_name = (_("Hide") if is_shown else _("Show")) + " " + tab.tab_description
            tab.menu_action = view_menu.addAction(item_name, lambda: self.toggle_tab(tab))

        view_menu = menubar.addMenu(_("&View"))
        add_toggle_action(view_menu, self.addresses_tab)
        add_toggle_action(view_menu, self.utxo_tab)
        add_toggle_action(view_menu, self.channels_tab)
        add_toggle_action(view_menu, self.contacts_tab)
        add_toggle_action(view_menu, self.console_tab)

        tools_menu = menubar.addMenu(_("&Tools"))  # type: QMenu
        preferences_action = tools_menu.addAction(_("Preferences"), self.settings_dialog)  # type: QAction
        if sys.platform == 'darwin':
            # "Settings"/"Preferences" are all reserved keywords in macOS.
            # preferences_action will get picked up based on name (and put into a standardized location,
            # and given a standard reserved hotkey)
            # Hence, this menu item will be at a "uniform location re macOS processes"
            preferences_action.setMenuRole(QAction.PreferencesRole)  # make sure OS recognizes it as preferences
            # Add another preferences item, to also have a "uniform location for Electrum between different OSes"
            tools_menu.addAction(_("Electrum-NMC preferences"), self.settings_dialog)

        tools_menu.addAction(_("&Network"), self.gui_object.show_network_dialog).setEnabled(bool(self.network))
        tools_menu.addAction(_("&Lightning Network"), self.gui_object.show_lightning_dialog).setEnabled(bool(self.wallet.has_lightning() and self.network))
        tools_menu.addAction(_("Local &Watchtower"), self.gui_object.show_watchtower_dialog).setEnabled(bool(self.network and self.network.local_watchtower))
        tools_menu.addAction(_("&Plugins"), self.plugins_dialog)
        tools_menu.addSeparator()
        tools_menu.addAction(_("&Sign/verify message"), self.sign_verify_message)
        tools_menu.addAction(_("&Encrypt/decrypt message"), self.encrypt_message)
        tools_menu.addSeparator()

        paytomany_menu = tools_menu.addAction(_("&Pay to many"), self.paytomany)

        raw_transaction_menu = tools_menu.addMenu(_("&Load transaction"))
        raw_transaction_menu.addAction(_("&From file"), self.do_process_from_file)
        raw_transaction_menu.addAction(_("&From text"), self.do_process_from_text)
        raw_transaction_menu.addAction(_("&From the blockchain"), self.do_process_from_txid)
        raw_transaction_menu.addAction(_("&From QR code"), self.read_tx_from_qrcode)
        self.raw_transaction_menu = raw_transaction_menu
        run_hook('init_menubar_tools', self, tools_menu)

        help_menu = menubar.addMenu(_("&Help"))
        help_menu.addAction(_("&About"), self.show_about)
        help_menu.addAction(_("&Check for updates"), self.show_update_check)
        help_menu.addAction(_("&Official website"), lambda: webopen("https://www.namecoin.org"))
        help_menu.addSeparator()
        help_menu.addAction(_("&Documentation"), lambda: webopen("http://docs.electrum.org/")).setShortcut(QKeySequence.HelpContents)
        help_menu.addAction(_("&Report Bug"), self.show_report_bug)
        help_menu.addSeparator()
        help_menu.addAction(_("&Donate to server"), self.donate_to_server)

        self.setMenuBar(menubar)

    def donate_to_server(self):
        d = self.network.get_donation_address()
        if d:
            host = self.network.get_parameters().server.host
            self.pay_to_URI('namecoin:%s?message=donation for %s'%(d, host))
        else:
            self.show_error(_('No donation address for this server'))

    def show_about(self):
        QMessageBox.about(self, "Electrum-NMC",
                          (_("Version")+" %s" % ELECTRUM_VERSION + "\n\n" +
                           _("Electrum-NMC's focus is speed, with low resource usage and simplifying Namecoin.") + " " +
                           _("You do not need to perform regular backups, because your wallet can be "
                              "recovered from a secret phrase that you can memorize or write on paper.") + " " +
                           _("Startup times are instant because it operates in conjunction with high-performance "
                              "servers that handle the most complicated parts of the Namecoin system.") + "\n\n" +
                           _("Uses icons from the Icons8 icon pack (icons8.com).")))

    def show_update_check(self, version=None):
        self.gui_object._update_check = UpdateCheck(latest_version=version)

    def show_report_bug(self):
        msg = ' '.join([
            _("Please report any bugs as issues on github:<br/>"),
            f'''<a href="{constants.GIT_REPO_ISSUES_URL}">{constants.GIT_REPO_ISSUES_URL}</a><br/><br/>''',
            _("Before reporting a bug, upgrade to the most recent version of Electrum-NMC (latest release or git HEAD), and include the version number in your report."),
            _("Try to explain not only what the bug is, but how it occurs.")
         ])
        self.show_message(msg, title="Electrum-NMC - " + _("Reporting Bugs"), rich_text=True)

    def notify_transactions(self):
        if self.tx_notification_queue.qsize() == 0:
            return
        if not self.wallet.up_to_date:
            return  # no notifications while syncing
        now = time.time()
        rate_limit = 20  # seconds
        if self.tx_notification_last_time + rate_limit > now:
            return
        self.tx_notification_last_time = now
        self.logger.info("Notifying GUI about new transactions")
        txns = []
        while True:
            try:
                txns.append(self.tx_notification_queue.get_nowait())
            except queue.Empty:
                break
        # Combine the transactions if there are at least three
        if len(txns) >= 3:
            total_amount = 0
            for tx in txns:
                tx_wallet_delta = self.wallet.get_wallet_delta(tx)
                if not tx_wallet_delta.is_relevant:
                    continue
                total_amount += tx_wallet_delta.delta
            self.notify(_("{} new transactions: Total amount received in the new transactions {}")
                        .format(len(txns), self.format_amount_and_units(total_amount)))
        else:
            for tx in txns:
                tx_wallet_delta = self.wallet.get_wallet_delta(tx)
                if not tx_wallet_delta.is_relevant:
                    continue
                self.notify(_("New transaction: {}").format(self.format_amount_and_units(tx_wallet_delta.delta)))

    def notify(self, message):
        if self.tray:
            try:
                # this requires Qt 5.9
                self.tray.showMessage("Electrum-NMC", message, read_QIcon("electrum_dark_icon"), 20000)
            except TypeError:
                self.tray.showMessage("Electrum-NMC", message, QSystemTrayIcon.Information, 20000)



    # custom wrappers for getOpenFileName and getSaveFileName, that remember the path selected by the user
    def getOpenFileName(self, title, filter = ""):
        directory = self.config.get('io_dir', os.path.expanduser('~'))
        fileName, __ = QFileDialog.getOpenFileName(self, title, directory, filter)
        if fileName and directory != os.path.dirname(fileName):
            self.config.set_key('io_dir', os.path.dirname(fileName), True)
        return fileName

    def getSaveFileName(self, title, filename, filter="",
                        *, default_extension: str = None,
                        default_filter: str = None) -> Optional[str]:
        directory = self.config.get('io_dir', os.path.expanduser('~'))
        path = os.path.join(directory, filename)

        file_dialog = QFileDialog(self, title, path, filter)
        file_dialog.setAcceptMode(QFileDialog.AcceptSave)
        if default_extension:
            # note: on MacOS, the selected filter's first extension seems to have priority over this...
            file_dialog.setDefaultSuffix(default_extension)
        if default_filter:
            assert default_filter in filter, f"default_filter={default_filter!r} does not appear in filter={filter!r}"
            file_dialog.selectNameFilter(default_filter)
        if file_dialog.exec() != QDialog.Accepted:
            return None

        selected_path = file_dialog.selectedFiles()[0]
        if selected_path and directory != os.path.dirname(selected_path):
            self.config.set_key('io_dir', os.path.dirname(selected_path), True)
        return selected_path

    def timer_actions(self):
        self.request_list.refresh_status()
        # Note this runs in the GUI thread
        if self.need_update.is_set():
            self.need_update.clear()
            self.update_wallet()
        elif not self.wallet.up_to_date:
            # this updates "synchronizing" progress
            self.update_status()
        # resolve aliases
        # FIXME this is a blocking network call that has a timeout of 5 sec
        self.payto_e.resolve()
        self.notify_transactions()

    def format_amount(self, x, is_diff=False, whitespaces=False):
        # x is in sats
        return self.config.format_amount(x, is_diff=is_diff, whitespaces=whitespaces)

    def format_amount_and_units(self, amount):
        # amount is in sats
        text = self.config.format_amount_and_units(amount)
        x = self.fx.format_amount_and_units(amount) if self.fx else None
        if text and x:
            text += ' (%s)'%x
        return text

    def format_fee_rate(self, fee_rate):
        return self.config.format_fee_rate(fee_rate)

    def get_decimal_point(self):
        return self.config.get_decimal_point()

    def base_unit(self):
        return self.config.get_base_unit()

    def connect_fields(self, window, btc_e, fiat_e, fee_e):

        def edit_changed(edit):
            if edit.follows:
                return
            edit.setStyleSheet(ColorScheme.DEFAULT.as_stylesheet())
            fiat_e.is_last_edited = (edit == fiat_e)
            amount = edit.get_amount()
            rate = self.fx.exchange_rate() if self.fx else Decimal('NaN')
            if rate.is_nan() or amount is None:
                if edit is fiat_e:
                    btc_e.setText("")
                    if fee_e:
                        fee_e.setText("")
                else:
                    fiat_e.setText("")
            else:
                if edit is fiat_e:
                    btc_e.follows = True
                    btc_e.setAmount(int(amount / Decimal(rate) * COIN))
                    btc_e.setStyleSheet(ColorScheme.BLUE.as_stylesheet())
                    btc_e.follows = False
                    if fee_e:
                        window.update_fee()
                else:
                    fiat_e.follows = True
                    fiat_e.setText(self.fx.ccy_amount_str(
                        amount * Decimal(rate) / COIN, False))
                    fiat_e.setStyleSheet(ColorScheme.BLUE.as_stylesheet())
                    fiat_e.follows = False

        btc_e.follows = False
        fiat_e.follows = False
        fiat_e.textChanged.connect(partial(edit_changed, fiat_e))
        btc_e.textChanged.connect(partial(edit_changed, btc_e))
        fiat_e.is_last_edited = False

    def update_status(self):
        if not self.wallet:
            return

        if self.network is None:
            text = _("Offline")
            icon = read_QIcon("status_disconnected.png")

        elif self.network.is_connected():
            server_height = self.network.get_server_height()
            server_lag = self.network.get_local_height() - server_height
            fork_str = "_fork" if len(self.network.get_blockchains())>1 else ""
            # Server height can be 0 after switching to a new server
            # until we get a headers subscription request response.
            # Display the synchronizing message in that case.
            if not self.wallet.up_to_date or server_height == 0:
                num_sent, num_answered = self.wallet.get_history_sync_state_details()
                text = ("{} ({}/{})"
                        .format(_("Synchronizing..."), num_answered, num_sent))
                icon = read_QIcon("status_waiting.png")
            elif server_lag > 1:
                text = _("Server is lagging ({} blocks)").format(server_lag)
                icon = read_QIcon("status_lagging%s.png"%fork_str)
            else:
                c, u, x = self.wallet.get_balance(hide_expired=True)
                text =  _("Balance" ) + ": %s "%(self.format_amount_and_units(c))
                if u:
                    text +=  " [%s unconfirmed]"%(self.format_amount(u, is_diff=True).strip())
                if x:
                    text +=  " [%s unmatured]"%(self.format_amount(x, is_diff=True).strip())
                if self.wallet.has_lightning():
                    l = self.wallet.lnworker.get_balance()
                    text += u'    \U000026a1 %s'%(self.format_amount_and_units(l).strip())
                # append fiat balance and price
                if self.fx.is_enabled():
                    text += self.fx.get_fiat_status_text(c + u + x,
                        self.base_unit(), self.get_decimal_point()) or ''
                if not self.network.proxy:
                    icon = read_QIcon("status_connected%s.png"%fork_str)
                else:
                    icon = read_QIcon("status_connected_proxy%s.png"%fork_str)

                # append name count
                name_confirmed_count, name_pending_count = get_wallet_name_count(self.wallet, self.network)
                text += ", {} {}, {} {}".format(name_confirmed_count, _("names"), name_pending_count, _("pending registration"))

                # append anonymous balance
                if self.config.get_anonymity_enabled():
                    listaddressgroupings = self.console.namespace.get('listaddressgroupings')
                    anonymous_addresses = listaddressgroupings(identifier="", name_encoding="ascii", collapse=True, wallet=self.wallet)
                    c, u, x = self.wallet.get_balance(anonymous_addresses, hide_expired=True)
                    text += ", " + _("Anonymous Balance" ) + ": %s "%(self.format_amount_and_units(c))
                    if u:
                        text +=  " [%s anonymous unconfirmed]"%(self.format_amount(u, is_diff=True).strip())
                    if x:
                        text +=  " [%s anonymous unmatured]"%(self.format_amount(x, is_diff=True).strip())
        else:
            if self.network.proxy:
                text = "{} ({})".format(_("Not connected"), _("proxy enabled"))
            else:
                text = _("Not connected")
            icon = read_QIcon("status_disconnected.png")

        self.tray.setToolTip("%s (%s)" % (text, self.wallet.basename()))
        self.balance_label.setText(text)
        if self.status_button:
            self.status_button.setIcon( icon )

    def update_wallet(self):
        self.update_status()
        if self.wallet.up_to_date or not self.network or not self.network.is_connected():
            self.update_tabs()

    def update_tabs(self, wallet=None):
        if wallet is None:
            wallet = self.wallet
        if wallet != self.wallet:
            return
        self.history_model.refresh('update_tabs')
        self.request_list.update()
        self.address_list.update()
        self.utxo_list.update()
        self.names_uno_list.update()
        self.contact_list.update()
        self.invoice_list.update()
        self.channels_list.update_rows.emit(wallet)
        self.update_completions()

    def create_channels_tab(self):
        self.channels_list = ChannelsList(self)
        t = self.channels_list.get_toolbar()
        return self.create_list_tab(self.channels_list, t)

    def create_history_tab(self):
        self.history_model = HistoryModel(self)
        self.history_list = l = HistoryList(self, self.history_model)
        self.history_model.set_view(self.history_list)
        l.searchable_list = l
        toolbar = l.create_toolbar(self.config)
        toolbar_shown = bool(self.config.get('show_toolbar_history', False))
        l.show_toolbar(toolbar_shown)
        return self.create_list_tab(l, toolbar)

    def show_address(self, addr):
        from . import address_dialog
        d = address_dialog.AddressDialog(self, addr)
        d.exec_()

    def show_channel(self, channel_id):
        from . import channel_details
        channel_details.ChannelDetailsDialog(self, channel_id).show()

    def show_transaction(self, tx, *, tx_desc=None):
        '''tx_desc is set only for txs created in the Send tab'''
        show_transaction(tx, parent=self, desc=tx_desc)

    def show_lightning_transaction(self, tx_item):
        from .lightning_tx_dialog import LightningTxDialog
        d = LightningTxDialog(self, tx_item)
        d.show()

    def create_receive_tab(self):
        # A 4-column grid layout.  All the stretch is in the last column.
        # The exchange rate plugin adds a fiat widget in column 2
        self.receive_grid = grid = QGridLayout()
        grid.setSpacing(8)
        grid.setColumnStretch(3, 1)

        self.receive_message_e = QLineEdit()
        grid.addWidget(QLabel(_('Description')), 0, 0)
        grid.addWidget(self.receive_message_e, 0, 1, 1, 4)
        self.receive_message_e.textChanged.connect(self.update_receive_qr)

        self.receive_amount_e = BTCAmountEdit(self.get_decimal_point)
        grid.addWidget(QLabel(_('Requested amount')), 1, 0)
        grid.addWidget(self.receive_amount_e, 1, 1)
        self.receive_amount_e.textChanged.connect(self.update_receive_qr)

        self.fiat_receive_e = AmountEdit(self.fx.get_currency if self.fx else '')
        if not self.fx or not self.fx.is_enabled():
            self.fiat_receive_e.setVisible(False)
        grid.addWidget(self.fiat_receive_e, 1, 2, Qt.AlignLeft)

        self.connect_fields(self, self.receive_amount_e, self.fiat_receive_e, None)
        self.connect_fields(self, self.amount_e, self.fiat_send_e, None)

        self.expires_combo = QComboBox()
        evl = sorted(pr_expiration_values.items())
        evl_keys = [i[0] for i in evl]
        evl_values = [i[1] for i in evl]
        default_expiry = self.config.get('request_expiry', PR_DEFAULT_EXPIRATION_WHEN_CREATING)
        try:
            i = evl_keys.index(default_expiry)
        except ValueError:
            i = 0
        self.expires_combo.addItems(evl_values)
        self.expires_combo.setCurrentIndex(i)
        self.expires_combo.setFixedWidth(self.receive_amount_e.width())
        def on_expiry(i):
            self.config.set_key('request_expiry', evl_keys[i])
        self.expires_combo.currentIndexChanged.connect(on_expiry)
        msg = ' '.join([
            _('Expiration date of your request.'),
            _('This information is seen by the recipient if you send them a signed payment request.'),
            _('Expired requests have to be deleted manually from your list, in order to free the corresponding Namecoin addresses.'),
            _('The namecoin address never expires and will always be part of this electrum-nmc wallet.'),
        ])
        grid.addWidget(HelpLabel(_('Expires after'), msg), 2, 0)
        grid.addWidget(self.expires_combo, 2, 1)
        self.expires_label = QLineEdit('')
        self.expires_label.setReadOnly(1)
        self.expires_label.setFocusPolicy(Qt.NoFocus)
        self.expires_label.hide()
        grid.addWidget(self.expires_label, 2, 1)

        self.clear_invoice_button = QPushButton(_('Clear'))
        self.clear_invoice_button.clicked.connect(self.clear_receive_tab)
        self.create_invoice_button = QPushButton(_('New Address'))
        self.create_invoice_button.setIcon(read_QIcon("bitcoin.png"))
        self.create_invoice_button.setToolTip('Create on-chain request')
        self.create_invoice_button.clicked.connect(lambda: self.create_invoice(False))
        self.receive_buttons = buttons = QHBoxLayout()
        buttons.addStretch(1)
        buttons.addWidget(self.clear_invoice_button)
        buttons.addWidget(self.create_invoice_button)
        if self.wallet.has_lightning():
            self.create_invoice_button.setText(_('New Address'))
            self.create_lightning_invoice_button = QPushButton(_('Lightning'))
            self.create_lightning_invoice_button.setToolTip('Create lightning request')
            self.create_lightning_invoice_button.setIcon(read_QIcon("lightning.png"))
            self.create_lightning_invoice_button.clicked.connect(lambda: self.create_invoice(True))
            buttons.addWidget(self.create_lightning_invoice_button)
        grid.addLayout(buttons, 4, 3, 1, 2)

        self.receive_payreq_e = ButtonsTextEdit()
        self.receive_payreq_e.setFont(QFont(MONOSPACE_FONT))
        self.receive_payreq_e.addCopyButton(self.app)
        self.receive_payreq_e.setReadOnly(True)
        self.receive_payreq_e.textChanged.connect(self.update_receive_qr)
        self.receive_payreq_e.setFocusPolicy(Qt.ClickFocus)

        self.receive_qr = QRCodeWidget(fixedSize=220)
        self.receive_qr.mouseReleaseEvent = lambda x: self.toggle_qr_window()
        self.receive_qr.enterEvent = lambda x: self.app.setOverrideCursor(QCursor(Qt.PointingHandCursor))
        self.receive_qr.leaveEvent = lambda x: self.app.setOverrideCursor(QCursor(Qt.ArrowCursor))

        self.receive_address_e = ButtonsTextEdit()
        self.receive_address_e.setFont(QFont(MONOSPACE_FONT))
        self.receive_address_e.addCopyButton(self.app)
        self.receive_address_e.setReadOnly(True)
        self.receive_address_e.textChanged.connect(self.update_receive_address_styling)

        qr_show = lambda: self.show_qrcode(str(self.receive_address_e.text()), _('Receiving address'), parent=self)
        qr_icon = "qrcode_white.png" if ColorScheme.dark_scheme else "qrcode.png"
        self.receive_address_e.addButton(qr_icon, qr_show, _("Show as QR code"))

        self.receive_requests_label = QLabel(_('Incoming payments'))

        from .request_list import RequestList
        self.request_list = RequestList(self)

        receive_tabs = QTabWidget()
        receive_tabs.addTab(self.receive_address_e, _('Address'))
        receive_tabs.addTab(self.receive_payreq_e, _('Request'))
        receive_tabs.addTab(self.receive_qr, _('QR Code'))
        receive_tabs.setCurrentIndex(self.config.get('receive_tabs_index', 0))
        receive_tabs.currentChanged.connect(lambda i: self.config.set_key('receive_tabs_index', i))
        receive_tabs_sp = receive_tabs.sizePolicy()
        receive_tabs_sp.setRetainSizeWhenHidden(True)
        receive_tabs.setSizePolicy(receive_tabs_sp)

        def maybe_hide_receive_tabs():
            receive_tabs.setVisible(bool(self.receive_payreq_e.text()))
        self.receive_payreq_e.textChanged.connect(maybe_hide_receive_tabs)
        maybe_hide_receive_tabs()

        # layout
        vbox_g = QVBoxLayout()
        vbox_g.addLayout(grid)
        vbox_g.addStretch()
        hbox = QHBoxLayout()
        hbox.addLayout(vbox_g)
        hbox.addStretch()
        hbox.addWidget(receive_tabs)

        w = QWidget()
        w.searchable_list = self.request_list
        vbox = QVBoxLayout(w)
        vbox.addLayout(hbox)

        vbox.addStretch(1)
        vbox.addWidget(self.receive_requests_label)
        vbox.addWidget(self.request_list)
        vbox.setStretchFactor(self.request_list, 1000)

        return w

    def delete_requests(self, keys):
        for key in keys:
            self.wallet.delete_request(key)
        self.request_list.update()
        self.clear_receive_tab()

    def delete_lightning_payreq(self, payreq_key):
        self.wallet.lnworker.delete_invoice(payreq_key)
        self.request_list.update()
        self.invoice_list.update()
        self.clear_receive_tab()

    def sign_payment_request(self, addr):
        alias = self.config.get('alias')
        if alias and self.alias_info:
            alias_addr, alias_name, validated = self.alias_info
            if alias_addr:
                if self.wallet.is_mine(alias_addr):
                    msg = _('This payment request will be signed.') + '\n' + _('Please enter your password')
                    password = None
                    if self.wallet.has_keystore_encryption():
                        password = self.password_dialog(msg)
                        if not password:
                            return
                    try:
                        self.wallet.sign_payment_request(addr, alias, alias_addr, password)
                    except Exception as e:
                        self.show_error(repr(e))
                        return
                else:
                    return

    def create_invoice(self, is_lightning):
        amount = self.receive_amount_e.get_amount()
        message = self.receive_message_e.text()
        expiry = self.config.get('request_expiry', PR_DEFAULT_EXPIRATION_WHEN_CREATING)
        if is_lightning:
            if not self.wallet.lnworker.channels:
                self.show_error(_("You need to open a Lightning channel first."))
                return
            # TODO maybe show a warning if amount exceeds lnworker.num_sats_can_receive (as in kivy)
            key = self.wallet.lnworker.add_request(amount, message, expiry)
        else:
            key = self.create_bitcoin_request(amount, message, expiry)
            if not key:
                return
            self.address_list.update()
        assert key is not None
        self.request_list.update()
        self.request_list.select_key(key)
        # clear request fields
        self.receive_amount_e.setText('')
        self.receive_message_e.setText('')
        # copy to clipboard
        r = self.wallet.get_request(key)
        content = r.invoice if r.is_lightning() else r.get_address()
        title = _('Invoice') if is_lightning else _('Address')
        self.do_copy(content, title=title)

    def create_bitcoin_request(self, amount, message, expiration) -> Optional[str]:
        addr = self.wallet.get_unused_address()
        if addr is None:
            if not self.wallet.is_deterministic():  # imported wallet
                msg = [
                    _('No more addresses in your wallet.'), ' ',
                    _('You are using a non-deterministic wallet, which cannot create new addresses.'), ' ',
                    _('If you want to create new addresses, use a deterministic wallet instead.'), '\n\n',
                    _('Creating a new payment request will reuse one of your addresses and overwrite an existing request. Continue anyway?'),
                   ]
                if not self.question(''.join(msg)):
                    return
                addr = self.wallet.get_receiving_address()
            else:  # deterministic wallet
                if not self.question(_("Warning: The next address will not be recovered automatically if you restore your wallet from seed; you may need to add it manually.\n\nThis occurs because you have too many unused addresses in your wallet. To avoid this situation, use the existing addresses first.\n\nCreate anyway?")):
                    return
                addr = self.wallet.create_new_address(False)
        req = self.wallet.make_payment_request(addr, amount, message, expiration)
        try:
            self.wallet.add_payment_request(req)
        except Exception as e:
            self.logger.exception('Error adding payment request')
            self.show_error(_('Error adding payment request') + ':\n' + repr(e))
        else:
            self.sign_payment_request(addr)
        return addr

    def do_copy(self, content: str, *, title: str = None) -> None:
        self.app.clipboard().setText(content)
        if title is None:
            tooltip_text = _("Text copied to clipboard").format(title)
        else:
            tooltip_text = _("{} copied to clipboard").format(title)
        QToolTip.showText(QCursor.pos(), tooltip_text, self)

    def clear_receive_tab(self):
        self.receive_payreq_e.setText('')
        self.receive_address_e.setText('')
        self.receive_message_e.setText('')
        self.receive_amount_e.setAmount(None)
        self.expires_label.hide()
        self.expires_combo.show()
        self.request_list.clearSelection()

    def toggle_qr_window(self):
        from . import qrwindow
        if not self.qr_window:
            self.qr_window = qrwindow.QR_Window(self)
            self.qr_window.setVisible(True)
            self.qr_window_geometry = self.qr_window.geometry()
        else:
            if not self.qr_window.isVisible():
                self.qr_window.setVisible(True)
                self.qr_window.setGeometry(self.qr_window_geometry)
            else:
                self.qr_window_geometry = self.qr_window.geometry()
                self.qr_window.setVisible(False)
        self.update_receive_qr()

    def show_send_tab(self):
        self.tabs.setCurrentIndex(self.tabs.indexOf(self.send_tab))

    def show_receive_tab(self):
        self.tabs.setCurrentIndex(self.tabs.indexOf(self.receive_tab))

    def update_receive_qr(self):
        uri = str(self.receive_payreq_e.text())
        if maybe_extract_bolt11_invoice(uri):
            # encode lightning invoices as uppercase so QR encoding can use
            # alphanumeric mode; resulting in smaller QR codes
            uri = uri.upper()
        self.receive_qr.setData(uri)
        if self.qr_window and self.qr_window.isVisible():
            self.qr_window.qrw.setData(uri)

    def update_receive_address_styling(self):
        addr = str(self.receive_address_e.text())
        if is_address(addr) and self.wallet.is_used(addr):
            self.receive_address_e.setStyleSheet(ColorScheme.RED.as_stylesheet(True))
            self.receive_address_e.setToolTip(_("This address has already been used. "
                                                "For better privacy, do not reuse it for new payments."))
        else:
            self.receive_address_e.setStyleSheet("")
            self.receive_address_e.setToolTip("")

    def create_send_tab(self):
        # A 4-column grid layout.  All the stretch is in the last column.
        # The exchange rate plugin adds a fiat widget in column 2
        self.send_grid = grid = QGridLayout()
        grid.setSpacing(8)
        grid.setColumnStretch(3, 1)

        from .paytoedit import PayToEdit
        self.amount_e = BTCAmountEdit(self.get_decimal_point)
        self.payto_e = PayToEdit(self)
        self.payto_e.addPasteButton(self.app)
        msg = _('Recipient of the funds.') + '\n\n'\
              + _('You may enter a Namecoin address, a label from your list of contacts (a list of completions will be proposed), or an alias (email-like address that forwards to a Namecoin address)')
        payto_label = HelpLabel(_('Pay to'), msg)
        grid.addWidget(payto_label, 1, 0)
        grid.addWidget(self.payto_e, 1, 1, 1, -1)

        completer = QCompleter()
        completer.setCaseSensitivity(False)
        self.payto_e.set_completer(completer)
        completer.setModel(self.completions)

        msg = _('Description of the transaction (not mandatory).') + '\n\n'\
              + _('The description is not sent to the recipient of the funds. It is stored in your wallet file, and displayed in the \'History\' tab.')
        description_label = HelpLabel(_('Description'), msg)
        grid.addWidget(description_label, 2, 0)
        self.message_e = FreezableLineEdit()
        self.message_e.setMinimumWidth(700)
        grid.addWidget(self.message_e, 2, 1, 1, -1)

        msg = _('Amount to be sent.') + '\n\n' \
              + _('The amount will be displayed in red if you do not have enough funds in your wallet.') + ' ' \
              + _('Note that if you have frozen some of your addresses, the available funds will be lower than your total balance.') + '\n\n' \
              + _('Keyboard shortcut: type "!" to send all your coins.')
        amount_label = HelpLabel(_('Amount'), msg)
        grid.addWidget(amount_label, 3, 0)
        grid.addWidget(self.amount_e, 3, 1)

        self.fiat_send_e = AmountEdit(self.fx.get_currency if self.fx else '')
        if not self.fx or not self.fx.is_enabled():
            self.fiat_send_e.setVisible(False)
        grid.addWidget(self.fiat_send_e, 3, 2)
        self.amount_e.frozen.connect(
            lambda: self.fiat_send_e.setFrozen(self.amount_e.isReadOnly()))

        self.max_button = EnterButton(_("Max"), self.spend_max)
        self.max_button.setFixedWidth(100)
        self.max_button.setCheckable(True)
        grid.addWidget(self.max_button, 3, 3)

        self.save_button = EnterButton(_("Save"), self.do_save_invoice)
        self.send_button = EnterButton(_("Pay") + "...", self.do_pay)
        self.clear_button = EnterButton(_("Clear"), self.do_clear)

        buttons = QHBoxLayout()
        buttons.addStretch(1)
        buttons.addWidget(self.clear_button)
        buttons.addWidget(self.save_button)
        buttons.addWidget(self.send_button)
        grid.addLayout(buttons, 6, 1, 1, 4)

        self.amount_e.shortcut.connect(self.spend_max)

        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.textEdited.connect(reset_max)
        self.fiat_send_e.textEdited.connect(reset_max)

        self.set_onchain(False)

        self.invoices_label = QLabel(_('Outgoing payments'))
        from .invoice_list import InvoiceList
        self.invoice_list = InvoiceList(self)

        vbox0 = QVBoxLayout()
        vbox0.addLayout(grid)
        hbox = QHBoxLayout()
        hbox.addLayout(vbox0)
        hbox.addStretch(1)
        w = QWidget()
        vbox = QVBoxLayout(w)
        vbox.addLayout(hbox)
        vbox.addStretch(1)
        vbox.addWidget(self.invoices_label)
        vbox.addWidget(self.invoice_list)
        vbox.setStretchFactor(self.invoice_list, 1000)
        w.searchable_list = self.invoice_list
        run_hook('create_send_tab', grid)
        return w

    def spend_max(self):
        if run_hook('abort_send', self):
            return
        outputs = self.payto_e.get_outputs(True)
        if not outputs:
            return
        make_tx = lambda fee_est: self.wallet.make_unsigned_transaction(
            coins=self.get_coins(),
            outputs=outputs,
            fee=fee_est,
            is_sweep=False)

        try:
            try:
                tx = make_tx(None)
            except (NotEnoughFunds, NoDynamicFeeEstimates) as e:
                # Check if we had enough funds excluding fees,
                # if so, still provide opportunity to set lower fees.
                tx = make_tx(0)
        except (MultipleSpendMaxTxOutputs, NotEnoughFunds) as e:
            self.max_button.setChecked(False)
            self.show_error(str(e))
            return

        self.max_button.setChecked(True)
        amount = tx.output_value_display()
        __, x_fee_amount = run_hook('get_tx_extra_fee', self.wallet, tx) or (None, 0)
        amount_after_all_fees = amount - x_fee_amount
        self.amount_e.setAmount(amount_after_all_fees)

    def get_contact_payto(self, key):
        _type, label = self.contacts.get(key)
        return label + '  <' + key + '>' if _type == 'address' else key

    def update_completions(self):
        l = [self.get_contact_payto(key) for key in self.contacts.keys()]
        self.completions.setStringList(l)

    @protected
    def protect(self, func, args, password):
        return func(*args, password)

    def read_outputs(self) -> List[PartialTxOutput]:
        if self.payment_request:
            outputs = self.payment_request.get_outputs()
        else:
            outputs = self.payto_e.get_outputs(self.max_button.isChecked())
        return outputs

    def check_send_tab_onchain_outputs_and_show_errors(self, outputs: List[PartialTxOutput]) -> bool:
        """Returns whether there are errors with outputs.
        Also shows error dialog to user if so.
        """
        if not outputs:
            self.show_error(_('No outputs'))
            return True

        for o in outputs:
            if o.scriptpubkey is None:
                self.show_error(_('Namecoin Address is None'))
                return True
            if o.value_display is None:
                self.show_error(_('Invalid Amount'))
                return True

        return False  # no errors

    def check_send_tab_payto_line_and_show_errors(self) -> bool:
        """Returns whether there are errors.
        Also shows error dialog to user if so.
        """
        pr = self.payment_request
        if pr:
            if pr.has_expired():
                self.show_error(_('Payment request has expired'))
                return True

        if not pr:
            errors = self.payto_e.get_errors()
            if errors:
                if len(errors) == 1 and not errors[0].is_multiline:
                    err = errors[0]
                    self.show_warning(_("Failed to parse 'Pay to' line") + ":\n" +
                                      f"{err.line_content[:40]}...\n\n"
                                      f"{err.exc!r}")
                else:
                    self.show_warning(_("Invalid Lines found:") + "\n\n" +
                                      '\n'.join([_("Line #") +
                                                 f"{err.idx+1}: {err.line_content[:40]}... ({err.exc!r})"
                                                 for err in errors]))
                return True

            if self.payto_e.is_alias and self.payto_e.validated is False:
                alias = self.payto_e.toPlainText()
                msg = _('WARNING: the alias "{}" could not be validated via an additional '
                        'security check, DNSSEC, and thus may not be correct.').format(alias) + '\n'
                msg += _('Do you wish to continue?')
                if not self.question(msg):
                    return True

        return False  # no errors

    def pay_lightning_invoice(self, invoice: str, *, amount_msat: Optional[int]):
        if amount_msat is None:
            raise Exception("missing amount for LN invoice")
        amount_sat = Decimal(amount_msat) / 1000
        # FIXME this is currently lying to user as we truncate to satoshis
        msg = _("Pay lightning invoice?") + '\n\n' + _("This will send {}?").format(self.format_amount_and_units(amount_sat))
        if not self.question(msg):
            return
        attempts = LN_NUM_PAYMENT_ATTEMPTS
        def task():
            self.wallet.lnworker.pay(invoice, amount_msat=amount_msat, attempts=attempts)
        self.do_clear()
        self.wallet.thread.add(task)
        self.invoice_list.update()

    def on_request_status(self, wallet, key, status):
        if wallet != self.wallet:
            return
        if key not in self.wallet.receive_requests:
            return
        if status == PR_PAID:
            self.notify(_('Payment received') + '\n' + key)
            self.need_update.set()

    def on_invoice_status(self, wallet, key):
        if wallet != self.wallet:
            return
        req = self.wallet.get_invoice(key)
        if req is None:
            return
        self.invoice_list.update_item(key, req)

    def on_payment_succeeded(self, wallet, key):
        description = self.wallet.get_label(key)
        self.notify(_('Payment succeeded') + '\n\n' + description)
        self.need_update.set()

    def on_payment_failed(self, wallet, key, reason):
        self.show_error(_('Payment failed') + '\n\n' + reason)

    def read_invoice(self):
        if self.check_send_tab_payto_line_and_show_errors():
            return
        if not self._is_onchain:
            invoice_str = self.payto_e.lightning_invoice
            if not invoice_str:
                return
            if not self.wallet.has_lightning():
                self.show_error(_('Lightning is disabled'))
                return
            invoice = LNInvoice.from_bech32(invoice_str)
            if invoice.get_amount_msat() is None:
                amount_sat = self.amount_e.get_amount()
                if amount_sat:
                    invoice.amount_msat = int(amount_sat * 1000)
                else:
                    self.show_error(_('No amount'))
                    return
            return invoice
        else:
            outputs = self.read_outputs()
            if self.check_send_tab_onchain_outputs_and_show_errors(outputs):
                return
            message = self.message_e.text()
            return self.wallet.create_invoice(
                outputs=outputs,
                message=message,
                pr=self.payment_request,
                URI=self.payto_URI)

    def do_save_invoice(self):
        invoice = self.read_invoice()
        if not invoice:
            return
        self.wallet.save_invoice(invoice)
        self.do_clear()
        self.invoice_list.update()

    def do_pay(self):
        invoice = self.read_invoice()
        if not invoice:
            return
        self.wallet.save_invoice(invoice)
        self.invoice_list.update()
        self.do_clear()
        self.do_pay_invoice(invoice)

    def pay_multiple_invoices(self, invoices):
        outputs = []
        for invoice in invoices:
            outputs += invoice.outputs
        self.pay_onchain_dialog(self.get_coins(), outputs)

    def do_pay_invoice(self, invoice: 'Invoice'):
        if invoice.type == PR_TYPE_LN:
            assert isinstance(invoice, LNInvoice)
            self.pay_lightning_invoice(invoice.invoice, amount_msat=invoice.get_amount_msat())
        elif invoice.type == PR_TYPE_ONCHAIN:
            assert isinstance(invoice, OnchainInvoice)
            self.pay_onchain_dialog(self.get_coins(), invoice.outputs)
        else:
            raise Exception('unknown invoice type')

    def get_coins(self, *, nonlocal_only=False) -> Sequence[PartialTxInput]:
        coins = self.get_manually_selected_coins()
        if coins is not None:
            return coins
        else:
            return self.wallet.get_spendable_coins(None, nonlocal_only=nonlocal_only)

    def get_manually_selected_coins(self) -> Optional[Sequence[PartialTxInput]]:
        """Return a list of selected coins or None.
        Note: None means selection is not being used,
              while an empty sequence means the user specifically selected that.
        """
        return self.utxo_list.get_spend_list()

    def pay_onchain_dialog(self, inputs: Sequence[PartialTxInput],
                           outputs: List[PartialTxOutput], *,
                           external_keypairs=None) -> None:
        # trustedcoin requires this
        if run_hook('abort_send', self):
            return
        is_sweep = bool(external_keypairs)
        make_tx = lambda fee_est: self.wallet.make_unsigned_transaction(
            coins=inputs,
            outputs=outputs,
            fee=fee_est,
            is_sweep=is_sweep)
        output_values = [x.value_display for x in outputs]
        if output_values.count('!') > 1:
            self.show_error(_("More than one output set to spend max"))
            return

        output_value = '!' if '!' in output_values else sum(output_values)
        d = ConfirmTxDialog(window=self, make_tx=make_tx, output_value=output_value, is_sweep=is_sweep)
        if d.not_enough_funds:
            # Check if we had enough funds excluding fees,
            # if so, still provide opportunity to set lower fees.
            if not d.have_enough_funds_assuming_zero_fees():
                self.show_message(_('Not Enough Funds'))
                return

        # shortcut to advanced preview (after "enough funds" check!)
        if self.config.get('advanced_preview'):
            self.preview_tx_dialog(make_tx=make_tx,
                                   external_keypairs=external_keypairs)
            return

        cancelled, is_send, password, tx = d.run()
        if cancelled:
            return
        if is_send:
            def sign_done(success):
                if success:
                    self.broadcast_or_show(tx)
            self.sign_tx_with_password(tx, callback=sign_done, password=password,
                                       external_keypairs=external_keypairs)
        else:
            self.preview_tx_dialog(make_tx=make_tx,
                                   external_keypairs=external_keypairs)

    def preview_tx_dialog(self, *, make_tx, external_keypairs=None):
        d = PreviewTxDialog(make_tx=make_tx, external_keypairs=external_keypairs,
                            window=self)
        d.show()

    def broadcast_or_show(self, tx: Transaction):
        if not tx.is_complete():
            self.show_transaction(tx)
            return
        if not self.network:
            self.show_error(_("You can't broadcast a transaction without a live network connection."))
            self.show_transaction(tx)
            return
        self.broadcast_transaction(tx)

    @protected
    def sign_tx(self, tx, *, callback, external_keypairs, password):
        self.sign_tx_with_password(tx, callback=callback, password=password, external_keypairs=external_keypairs)

    def sign_tx_with_password(self, tx: PartialTransaction, *, callback, password, external_keypairs=None):
        '''Sign the transaction in a separate thread.  When done, calls
        the callback with a success code of True or False.
        '''
        def on_success(result):
            callback(True)
        def on_failure(exc_info):
            self.on_error(exc_info)
            callback(False)
        on_success = run_hook('tc_sign_wrapper', self.wallet, tx, on_success, on_failure) or on_success
        if external_keypairs:
            # can sign directly
            task = partial(tx.sign, external_keypairs)
        else:
            task = partial(self.wallet.sign_transaction, tx, password)
        msg = _('Signing transaction...')
        WaitingDialog(self, msg, task, on_success, on_failure)

    def broadcast_transaction(self, tx: Transaction):

        def broadcast_thread():
            # non-GUI thread
            pr = self.payment_request
            if pr and pr.has_expired():
                self.payment_request = None
                return False, _("Invoice has expired")
            try:
                self.network.run_from_another_thread(self.network.broadcast_transaction(tx))
            except TxBroadcastError as e:
                return False, e.get_message_for_gui()
            except BestEffortRequestFailed as e:
                return False, repr(e)
            # success
            txid = tx.txid()
            if pr:
                self.payment_request = None
                refund_address = self.wallet.get_receiving_address()
                coro = pr.send_payment_and_receive_paymentack(tx.serialize(), refund_address)
                fut = asyncio.run_coroutine_threadsafe(coro, self.network.asyncio_loop)
                ack_status, ack_msg = fut.result(timeout=20)
                self.logger.info(f"Payment ACK: {ack_status}. Ack message: {ack_msg}")
            return True, txid

        # Capture current TL window; override might be removed on return
        parent = self.top_level_window(lambda win: isinstance(win, MessageBoxMixin))

        def broadcast_done(result):
            # GUI thread
            if result:
                success, msg = result
                if success:
                    parent.show_message(_('Payment sent.') + '\n' + msg)
                    self.invoice_list.update()
                else:
                    msg = msg or ''
                    parent.show_error(msg)

        WaitingDialog(self, _('Broadcasting transaction...'),
                      broadcast_thread, broadcast_done, self.on_error)

    def mktx_for_open_channel(self, funding_sat):
        coins = self.get_coins(nonlocal_only=True)
        make_tx = lambda fee_est: self.wallet.lnworker.mktx_for_open_channel(coins=coins,
                                                                             funding_sat=funding_sat,
                                                                             fee_est=fee_est)
        return make_tx

    def open_channel(self, connect_str, funding_sat, push_amt):
        try:
            extract_nodeid(connect_str)
        except ConnStringFormatError as e:
            self.show_error(str(e))
            return
        # use ConfirmTxDialog
        # we need to know the fee before we broadcast, because the txid is required
        make_tx = self.mktx_for_open_channel(funding_sat)
        d = ConfirmTxDialog(window=self, make_tx=make_tx, output_value=funding_sat, is_sweep=False)
        # disable preview button because the user must not broadcast tx before establishment_flow
        d.preview_button.setEnabled(False)
        cancelled, is_send, password, funding_tx = d.run()
        if not is_send:
            return
        if cancelled:
            return
        # read funding_sat from tx; converts '!' to int value
        funding_sat = funding_tx.output_value_for_address(ln_dummy_address())
        def task():
            return self.wallet.lnworker.open_channel(connect_str=connect_str,
                                                     funding_tx=funding_tx,
                                                     funding_sat=funding_sat,
                                                     push_amt_sat=push_amt,
                                                     password=password)
        def on_success(args):
            chan, funding_tx = args
            n = chan.constraints.funding_txn_minimum_depth
            message = '\n'.join([
                _('Channel established.'),
                _('Remote peer ID') + ':' + chan.node_id.hex(),
                _('This channel will be usable after {} confirmations').format(n)
            ])
            if not funding_tx.is_complete():
                message += '\n\n' + _('Please sign and broadcast the funding transaction')
            self.show_message(message)
            if not funding_tx.is_complete():
                self.show_transaction(funding_tx)

        def on_failure(exc_info):
            type_, e, traceback = exc_info
            self.show_error(_('Could not open channel: {}').format(repr(e)))
        WaitingDialog(self, _('Opening channel...'), task, on_success, on_failure)

    def query_choice(self, msg, choices):
        # Needed by QtHandler for hardware wallets
        dialog = WindowModalDialog(self.top_level_window())
        clayout = ChoicesLayout(msg, choices)
        vbox = QVBoxLayout(dialog)
        vbox.addLayout(clayout.layout())
        vbox.addLayout(Buttons(OkButton(dialog)))
        if not dialog.exec_():
            return None
        return clayout.selected_index()

    def lock_amount(self, b: bool) -> None:
        self.amount_e.setFrozen(b)
        self.max_button.setEnabled(not b)

    def prepare_for_payment_request(self):
        self.show_send_tab()
        self.payto_e.is_pr = True
        for e in [self.payto_e, self.message_e]:
            e.setFrozen(True)
        self.lock_amount(True)
        self.payto_e.setText(_("please wait..."))
        return True

    def delete_invoices(self, keys):
        for key in keys:
            self.wallet.delete_invoice(key)
        self.invoice_list.update()

    def payment_request_ok(self):
        pr = self.payment_request
        if not pr:
            return
        key = pr.get_id()
        invoice = self.wallet.get_invoice(key)
        if invoice and self.wallet.get_invoice_status(invoice) == PR_PAID:
            self.show_message("invoice already paid")
            self.do_clear()
            self.payment_request = None
            return
        self.payto_e.is_pr = True
        if not pr.has_expired():
            self.payto_e.setGreen()
        else:
            self.payto_e.setExpired()
        self.payto_e.setText(pr.get_requestor())
        self.amount_e.setAmount(pr.get_amount())
        self.message_e.setText(pr.get_memo())
        # signal to set fee
        self.amount_e.textEdited.emit("")

    def payment_request_error(self):
        pr = self.payment_request
        if not pr:
            return
        self.show_message(pr.error)
        self.payment_request = None
        self.do_clear()

    def on_pr(self, request: 'paymentrequest.PaymentRequest'):
        self.set_onchain(True)
        self.payment_request = request
        if self.payment_request.verify(self.contacts):
            self.payment_request_ok_signal.emit()
        else:
            self.payment_request_error_signal.emit()

    def parse_lightning_invoice(self, invoice):
        """Parse ln invoice, and prepare the send tab for it."""
        try:
            lnaddr = lndecode(invoice, expected_hrp=constants.net.SEGWIT_HRP)
        except Exception as e:
            raise LnDecodeException(e) from e
        pubkey = bh2u(lnaddr.pubkey.serialize())
        for k,v in lnaddr.tags:
            if k == 'd':
                description = v
                break
        else:
             description = ''
        self.payto_e.setFrozen(True)
        self.payto_e.setText(pubkey)
        self.message_e.setText(description)
        if lnaddr.get_amount_sat() is not None:
            self.amount_e.setAmount(lnaddr.get_amount_sat())
        #self.amount_e.textEdited.emit("")
        self.set_onchain(False)

    def set_onchain(self, b):
        self._is_onchain = b
        self.max_button.setEnabled(b)

    def pay_to_URI(self, URI):
        if not URI:
            return
        try:
            out = util.parse_URI(URI, self.on_pr)
        except InvalidBitcoinURI as e:
            self.show_error(_("Error parsing URI") + f":\n{e}")
            return
        self.show_send_tab()
        self.payto_URI = out
        r = out.get('r')
        sig = out.get('sig')
        name = out.get('name')
        if r or (name and sig):
            self.prepare_for_payment_request()
            return
        address = out.get('address')
        amount = out.get('amount')
        label = out.get('label')
        message = out.get('message')
        # use label as description (not BIP21 compliant)
        if label and not message:
            message = label
        if address:
            self.payto_e.setText(address)
        if message:
            self.message_e.setText(message)
        if amount:
            self.amount_e.setAmount(amount)
            self.amount_e.textEdited.emit("")


    def do_clear(self):
        self.max_button.setChecked(False)
        self.payment_request = None
        self.payto_URI = None
        self.payto_e.is_pr = False
        self.set_onchain(False)
        for e in [self.payto_e, self.message_e, self.amount_e]:
            e.setText('')
            e.setFrozen(False)
        self.update_status()
        run_hook('do_clear', self)

    def set_frozen_state_of_addresses(self, addrs, freeze: bool):
        self.wallet.set_frozen_state_of_addresses(addrs, freeze)
        self.address_list.update()
        self.utxo_list.update()
        self.names_uno_list.update()

    def set_frozen_state_of_coins(self, utxos: Sequence[PartialTxInput], freeze: bool):
        self.wallet.set_frozen_state_of_coins(utxos, freeze)
        self.utxo_list.update()

    def create_list_tab(self, l, toolbar=None):
        w = QWidget()
        w.searchable_list = l
        vbox = QVBoxLayout()
        w.setLayout(vbox)
        #vbox.setContentsMargins(0, 0, 0, 0)
        #vbox.setSpacing(0)
        if toolbar:
            vbox.addLayout(toolbar)
        vbox.addWidget(l)
        return w

    def create_addresses_tab(self):
        from .address_list import AddressList
        self.address_list = l = AddressList(self)
        toolbar = l.create_toolbar(self.config)
        toolbar_shown = bool(self.config.get('show_toolbar_addresses', False))
        l.show_toolbar(toolbar_shown)
        return self.create_list_tab(l, toolbar)

    def create_utxo_tab(self):
        from .utxo_list import UTXOList
        self.utxo_list = UTXOList(self)
        return self.create_list_tab(self.utxo_list)

    def create_contacts_tab(self):
        from .contact_list import ContactList
        self.contact_list = l = ContactList(self)
        return self.create_list_tab(l)

    def remove_address(self, addr):
        if not self.question(_("Do you want to remove {} from your wallet?").format(addr)):
            return
        try:
            self.wallet.delete_address(addr)
        except UserFacingException as e:
            self.show_error(str(e))
        else:
            self.need_update.set()  # history, addresses, coins
            self.clear_receive_tab()

    def paytomany(self):
        self.show_send_tab()
        self.payto_e.paytomany()
        msg = '\n'.join([
            _('Enter a list of outputs in the \'Pay to\' field.'),
            _('One output per line.'),
            _('Format: address, amount'),
            _('You may load a CSV file using the file icon.')
        ])
        self.show_message(msg, title=_('Pay to many'))

    def payto_contacts(self, labels):
        paytos = [self.get_contact_payto(label) for label in labels]
        self.show_send_tab()
        if len(paytos) == 1:
            self.payto_e.setText(paytos[0])
            self.amount_e.setFocus()
        else:
            text = "\n".join([payto + ", 0" for payto in paytos])
            self.payto_e.setText(text)
            self.payto_e.setFocus()

    def set_contact(self, label, address):
        if not is_address(address):
            self.show_error(_('Invalid Address'))
            self.contact_list.update()  # Displays original unchanged value
            return False
        self.contacts[address] = ('address', label)
        self.contact_list.update()
        self.history_list.update()
        self.update_completions()
        return True

    def delete_contacts(self, labels):
        if not self.question(_("Remove {} from your list of contacts?")
                             .format(" + ".join(labels))):
            return
        for label in labels:
            self.contacts.pop(label)
        self.history_list.update()
        self.contact_list.update()
        self.update_completions()

    def show_onchain_invoice(self, invoice: OnchainInvoice):
        amount_str = self.format_amount(invoice.amount_sat) + ' ' + self.base_unit()
        d = WindowModalDialog(self, _("Onchain Invoice"))
        vbox = QVBoxLayout(d)
        grid = QGridLayout()
        grid.addWidget(QLabel(_("Amount") + ':'), 1, 0)
        grid.addWidget(QLabel(amount_str), 1, 1)
        if len(invoice.outputs) == 1:
            grid.addWidget(QLabel(_("Address") + ':'), 2, 0)
            grid.addWidget(QLabel(invoice.get_address()), 2, 1)
        else:
            outputs_str = '\n'.join(map(lambda x: x.address + ' : ' + self.format_amount(x.value)+ self.base_unit(), invoice.outputs))
            grid.addWidget(QLabel(_("Outputs") + ':'), 2, 0)
            grid.addWidget(QLabel(outputs_str), 2, 1)
        grid.addWidget(QLabel(_("Description") + ':'), 3, 0)
        grid.addWidget(QLabel(invoice.message), 3, 1)
        if invoice.exp:
            grid.addWidget(QLabel(_("Expires") + ':'), 4, 0)
            grid.addWidget(QLabel(format_time(invoice.exp + invoice.time)), 4, 1)
        if invoice.bip70:
            pr = paymentrequest.PaymentRequest(bytes.fromhex(invoice.bip70))
            pr.verify(self.contacts)
            grid.addWidget(QLabel(_("Requestor") + ':'), 5, 0)
            grid.addWidget(QLabel(pr.get_requestor()), 5, 1)
            grid.addWidget(QLabel(_("Signature") + ':'), 6, 0)
            grid.addWidget(QLabel(pr.get_verify_status()), 6, 1)
            def do_export():
                key = pr.get_id()
                name = str(key) + '.bip70'
                fn = self.getSaveFileName(_("Save invoice to file"), name, filter="*.bip70")
                if not fn:
                    return
                with open(fn, 'wb') as f:
                    data = f.write(pr.raw)
                self.show_message(_('BIP70 invoice saved as' + ' ' + fn))
            exportButton = EnterButton(_('Export'), do_export)
            buttons = Buttons(exportButton, CloseButton(d))
        else:
            buttons = Buttons(CloseButton(d))
        vbox.addLayout(grid)
        vbox.addLayout(buttons)
        d.exec_()

    def show_lightning_invoice(self, invoice: LNInvoice):
        lnaddr = lndecode(invoice.invoice, expected_hrp=constants.net.SEGWIT_HRP)
        d = WindowModalDialog(self, _("Lightning Invoice"))
        vbox = QVBoxLayout(d)
        grid = QGridLayout()
        grid.addWidget(QLabel(_("Node ID") + ':'), 0, 0)
        grid.addWidget(QLabel(lnaddr.pubkey.serialize().hex()), 0, 1)
        grid.addWidget(QLabel(_("Amount") + ':'), 1, 0)
        # TODO: Namecoin: use invoice.amount_display (to hide 0.01 NMC in name
        # coins).
        amount_str = self.format_amount(invoice.get_amount_sat()) + ' ' + self.base_unit()
        grid.addWidget(QLabel(amount_str), 1, 1)
        grid.addWidget(QLabel(_("Description") + ':'), 2, 0)
        grid.addWidget(QLabel(invoice.message), 2, 1)
        grid.addWidget(QLabel(_("Hash") + ':'), 3, 0)
        payhash_e = ButtonsLineEdit(lnaddr.paymenthash.hex())
        payhash_e.addCopyButton(self.app)
        payhash_e.setReadOnly(True)
        vbox.addWidget(payhash_e)
        grid.addWidget(payhash_e, 3, 1)
        if invoice.exp:
            grid.addWidget(QLabel(_("Expires") + ':'), 4, 0)
            grid.addWidget(QLabel(format_time(invoice.time + invoice.exp)), 4, 1)
        vbox.addLayout(grid)
        invoice_e = ShowQRTextEdit()
        invoice_e.addCopyButton(self.app)
        invoice_e.setText(invoice.invoice)
        vbox.addWidget(invoice_e)
        vbox.addLayout(Buttons(CloseButton(d),))
        d.exec_()

    def create_console_tab(self):
        from .console import Console
        self.console = console = Console()
        return console

    def update_console(self):
        console = self.console
        console.history = self.wallet.db.get("qt-console-history", [])
        console.history_index = len(console.history)

        console.updateNamespace({
            'wallet': self.wallet,
            'network': self.network,
            'plugins': self.gui_object.plugins,
            'window': self,
            'config': self.config,
            'electrum': electrum,
            'daemon': self.gui_object.daemon,
            'util': util,
            'bitcoin': bitcoin,
            'lnutil': lnutil,
        })

        c = commands.Commands(config=self.config,
                              network=self.network,
                              callback=lambda: self.console.set_json(True))
        methods = {}
        def mkfunc(f, method):
            return lambda *args, **kwargs: f(method,
                                             args,
                                             self.password_dialog,
                                             **{**kwargs, 'wallet': self.wallet})
        for m in dir(c):
            if m[0]=='_' or m in ['network','wallet','config','daemon']: continue
            methods[m] = mkfunc(c._run, m)

        console.updateNamespace(methods)

    def create_status_bar(self):

        sb = QStatusBar()
        sb.setFixedHeight(35)

        self.balance_label = QLabel("Loading wallet...")
        self.balance_label.setTextInteractionFlags(Qt.TextSelectableByMouse)
        self.balance_label.setStyleSheet("""QLabel { padding: 0 }""")
        sb.addWidget(self.balance_label)

        self.search_box = QLineEdit()
        self.search_box.textChanged.connect(self.do_search)
        self.search_box.hide()
        sb.addPermanentWidget(self.search_box)

        self.update_check_button = QPushButton("")
        self.update_check_button.setFlat(True)
        self.update_check_button.setCursor(QCursor(Qt.PointingHandCursor))
        self.update_check_button.setIcon(read_QIcon("update.png"))
        self.update_check_button.hide()
        sb.addPermanentWidget(self.update_check_button)

        self.password_button = StatusBarButton(QIcon(), _("Password"), self.change_password_dialog )
        sb.addPermanentWidget(self.password_button)

        sb.addPermanentWidget(StatusBarButton(read_QIcon("preferences.png"), _("Preferences"), self.settings_dialog ) )
        self.seed_button = StatusBarButton(read_QIcon("seed.png"), _("Seed"), self.show_seed_dialog )
        sb.addPermanentWidget(self.seed_button)
        self.lightning_button = None
        if self.wallet.has_lightning() and self.network:
            self.lightning_button = StatusBarButton(read_QIcon("lightning_disconnected.png"), _("Lightning Network"), self.gui_object.show_lightning_dialog)
            self.update_lightning_icon()
            sb.addPermanentWidget(self.lightning_button)
        self.status_button = None
        if self.network:
            self.status_button = StatusBarButton(read_QIcon("status_disconnected.png"), _("Network"), self.gui_object.show_network_dialog)
            sb.addPermanentWidget(self.status_button)
        run_hook('create_status_bar', sb)
        self.setStatusBar(sb)

    def create_coincontrol_statusbar(self):
        self.coincontrol_sb = sb = QStatusBar()
        sb.setSizeGripEnabled(False)
        #sb.setFixedHeight(3 * char_width_in_lineedit())
        sb.setStyleSheet('QStatusBar::item {border: None;} '
                         + ColorScheme.GREEN.as_stylesheet(True))

        self.coincontrol_label = QLabel()
        self.coincontrol_label.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Preferred)
        self.coincontrol_label.setTextInteractionFlags(Qt.TextSelectableByMouse)
        sb.addWidget(self.coincontrol_label)

        clear_cc_button = EnterButton(_('Reset'), lambda: self.utxo_list.set_spend_list(None))
        clear_cc_button.setStyleSheet("margin-right: 5px;")
        sb.addPermanentWidget(clear_cc_button)

        sb.setVisible(False)
        return sb

    def set_coincontrol_msg(self, msg: Optional[str]) -> None:
        if not msg:
            self.coincontrol_label.setText("")
            self.coincontrol_sb.setVisible(False)
            return
        self.coincontrol_label.setText(msg)
        self.coincontrol_sb.setVisible(True)

    def update_lightning_icon(self):
        if self.lightning_button is None:
            return
        if self.network.lngossip is None:
            return

        # display colorful lightning icon to signal connection
        self.lightning_button.setIcon(read_QIcon("lightning.png"))

        cur, total, progress_percent = self.network.lngossip.get_sync_progress_estimate()
        # self.logger.debug(f"updating lngossip sync progress estimate: cur={cur}, total={total}")
        progress_str = "??%"
        if progress_percent is not None:
            progress_str = f"{progress_percent}%"
        if progress_percent and progress_percent >= 100:
            self.lightning_button.setMaximumWidth(25)
            self.lightning_button.setText('')
            self.lightning_button.setToolTip(_("The Lightning Network graph is fully synced."))
        else:
            self.lightning_button.setMaximumWidth(25 + 4 * char_width_in_lineedit())
            self.lightning_button.setText(progress_str)
            self.lightning_button.setToolTip(_("The Lightning Network graph is syncing...\n"
                                               "Payments are more likely to succeed with a more complete graph."))

    def update_lock_icon(self):
        icon = read_QIcon("lock.png") if self.wallet.has_password() else read_QIcon("unlock.png")
        self.password_button.setIcon(icon)

    def update_buttons_on_seed(self):
        self.seed_button.setVisible(self.wallet.has_seed())
        self.password_button.setVisible(self.wallet.may_have_password())

    def change_password_dialog(self):
        from electrum.storage import StorageEncryptionVersion
        if self.wallet.get_available_storage_encryption_version() == StorageEncryptionVersion.XPUB_PASSWORD:
            from .password_dialog import ChangePasswordDialogForHW
            d = ChangePasswordDialogForHW(self, self.wallet)
            ok, encrypt_file = d.run()
            if not ok:
                return

            try:
                hw_dev_pw = self.wallet.keystore.get_password_for_storage_encryption()
            except UserCancelled:
                return
            except BaseException as e:
                self.logger.exception('')
                self.show_error(repr(e))
                return
            old_password = hw_dev_pw if self.wallet.has_password() else None
            new_password = hw_dev_pw if encrypt_file else None
        else:
            from .password_dialog import ChangePasswordDialogForSW
            d = ChangePasswordDialogForSW(self, self.wallet)
            ok, old_password, new_password, encrypt_file = d.run()

        if not ok:
            return
        try:
            self.wallet.update_password(old_password, new_password, encrypt_storage=encrypt_file)
        except InvalidPassword as e:
            self.show_error(str(e))
            return
        except BaseException:
            self.logger.exception('Failed to update password')
            self.show_error(_('Failed to update password'))
            return
        msg = _('Password was updated successfully') if self.wallet.has_password() else _('Password is disabled, this wallet is not protected')
        self.show_message(msg, title=_("Success"))
        self.update_lock_icon()

    def toggle_search(self):
        self.search_box.setHidden(not self.search_box.isHidden())
        if not self.search_box.isHidden():
            self.search_box.setFocus(1)
        else:
            self.do_search('')

    def do_search(self, t):
        tab = self.tabs.currentWidget()
        if hasattr(tab, 'searchable_list'):
            tab.searchable_list.filter(t)

    def new_contact_dialog(self):
        d = WindowModalDialog(self, _("New Contact"))
        vbox = QVBoxLayout(d)
        vbox.addWidget(QLabel(_('New Contact') + ':'))
        grid = QGridLayout()
        line1 = QLineEdit()
        line1.setFixedWidth(32 * char_width_in_lineedit())
        line2 = QLineEdit()
        line2.setFixedWidth(32 * char_width_in_lineedit())
        grid.addWidget(QLabel(_("Address")), 1, 0)
        grid.addWidget(line1, 1, 1)
        grid.addWidget(QLabel(_("Name")), 2, 0)
        grid.addWidget(line2, 2, 1)
        vbox.addLayout(grid)
        vbox.addLayout(Buttons(CancelButton(d), OkButton(d)))
        if d.exec_():
            self.set_contact(line2.text(), line1.text())

    def show_wallet_info(self):
        dialog = WindowModalDialog(self, _("Wallet Information"))
        dialog.setMinimumSize(500, 100)
        vbox = QVBoxLayout()
        wallet_type = self.wallet.db.get('wallet_type', '')
        if self.wallet.is_watching_only():
            wallet_type += ' [{}]'.format(_('watching-only'))
        seed_available = _('True') if self.wallet.has_seed() else _('False')
        keystore_types = [k.get_type_text() for k in self.wallet.get_keystores()]
        grid = QGridLayout()
        basename = os.path.basename(self.wallet.storage.path)
        grid.addWidget(QLabel(_("Wallet name")+ ':'), 0, 0)
        grid.addWidget(QLabel(basename), 0, 1)
        grid.addWidget(QLabel(_("Wallet type")+ ':'), 1, 0)
        grid.addWidget(QLabel(wallet_type), 1, 1)
        grid.addWidget(QLabel(_("Script type")+ ':'), 2, 0)
        grid.addWidget(QLabel(self.wallet.txin_type), 2, 1)
        grid.addWidget(QLabel(_("Seed available") + ':'), 3, 0)
        grid.addWidget(QLabel(str(seed_available)), 3, 1)
        if len(keystore_types) <= 1:
            grid.addWidget(QLabel(_("Keystore type") + ':'), 4, 0)
            ks_type = str(keystore_types[0]) if keystore_types else _('No keystore')
            grid.addWidget(QLabel(ks_type), 4, 1)
        # lightning
        grid.addWidget(QLabel(_('Lightning') + ':'), 5, 0)
        if self.wallet.can_have_lightning():
            grid.addWidget(QLabel(_('Enabled')), 5, 1)
            local_nodeid = QLabel(bh2u(self.wallet.lnworker.node_keypair.pubkey))
            local_nodeid.setTextInteractionFlags(Qt.TextSelectableByMouse)
            grid.addWidget(QLabel(_('Lightning Node ID:')), 6, 0)
            grid.addWidget(local_nodeid, 6, 1, 1, 3)
        else:
            grid.addWidget(QLabel(_("Not available for this wallet.")), 5, 1)
            grid.addWidget(HelpButton(_("Lightning is currently restricted to HD wallets with p2wpkh addresses.")), 5, 2)
        vbox.addLayout(grid)

        labels_clayout = None

        if self.wallet.is_deterministic():
            keystores = self.wallet.get_keystores()

            ks_stack = QStackedWidget()

            def select_ks(index):
                ks_stack.setCurrentIndex(index)

            # only show the combobox in case multiple accounts are available
            if len(keystores) > 1:
                def label(idx, ks):
                    if isinstance(self.wallet, Multisig_Wallet) and hasattr(ks, 'label'):
                        return _("cosigner") + f' {idx+1}: {ks.get_type_text()} {ks.label}'
                    else:
                        return _("keystore") + f' {idx+1}'

                labels = [label(idx, ks) for idx, ks in enumerate(self.wallet.get_keystores())]

                on_click = lambda clayout: select_ks(clayout.selected_index())
                labels_clayout = ChoicesLayout(_("Select keystore"), labels, on_click)
                vbox.addLayout(labels_clayout.layout())

            for ks in keystores:
                ks_w = QWidget()
                ks_vbox = QVBoxLayout()
                ks_vbox.setContentsMargins(0, 0, 0, 0)
                ks_w.setLayout(ks_vbox)

                mpk_text = ShowQRTextEdit(ks.get_master_public_key())
                mpk_text.setMaximumHeight(150)
                mpk_text.addCopyButton(self.app)
                run_hook('show_xpub_button', mpk_text, ks)

                der_path_hbox = QHBoxLayout()
                der_path_hbox.setContentsMargins(0, 0, 0, 0)

                der_path_hbox.addWidget(QLabel(_("Derivation path") + ':'))
                der_path_text = QLabel(ks.get_derivation_prefix() or _("unknown"))
                der_path_text.setTextInteractionFlags(Qt.TextSelectableByMouse)
                der_path_hbox.addWidget(der_path_text)
                der_path_hbox.addStretch()

                ks_vbox.addWidget(QLabel(_("Master Public Key")))
                ks_vbox.addWidget(mpk_text)
                ks_vbox.addLayout(der_path_hbox)

                ks_stack.addWidget(ks_w)

            select_ks(0)
            vbox.addWidget(ks_stack)

        vbox.addStretch(1)
        btn_export_info = run_hook('wallet_info_buttons', self, dialog)
        btn_close = CloseButton(dialog)
        btns = Buttons(btn_export_info, btn_close)
        vbox.addLayout(btns)
        dialog.setLayout(vbox)
        dialog.exec_()

    def remove_wallet(self):
        if self.question('\n'.join([
                _('Delete wallet file?'),
                "%s"%self.wallet.storage.path,
                _('If your wallet contains funds, make sure you have saved its seed.')])):
            self._delete_wallet()

    @protected
    def _delete_wallet(self, password):
        wallet_path = self.wallet.storage.path
        basename = os.path.basename(wallet_path)
        r = self.gui_object.daemon.delete_wallet(wallet_path)
        self.close()
        if r:
            self.show_error(_("Wallet removed: {}").format(basename))
        else:
            self.show_error(_("Wallet file not found: {}").format(basename))

    @protected
    def show_seed_dialog(self, password):
        if not self.wallet.has_seed():
            self.show_message(_('This wallet has no seed'))
            return
        keystore = self.wallet.get_keystore()
        try:
            seed = keystore.get_seed(password)
            passphrase = keystore.get_passphrase(password)
        except BaseException as e:
            self.show_error(repr(e))
            return
        from .seed_dialog import SeedDialog
        d = SeedDialog(self, seed, passphrase)
        d.exec_()

    def show_qrcode(self, data, title = _("QR code"), parent=None, *,
                    help_text=None, show_copy_text_btn=False):
        if not data:
            return
        d = QRDialog(data, parent or self, title, help_text=help_text,
                     show_copy_text_btn=show_copy_text_btn)
        d.exec_()

    @protected
    def show_private_key(self, address, password):
        if not address:
            return
        try:
            pk = self.wallet.export_private_key(address, password)
        except Exception as e:
            self.logger.exception('')
            self.show_message(repr(e))
            return
        xtype = bitcoin.deserialize_privkey(pk)[0]
        d = WindowModalDialog(self, _("Private key"))
        d.setMinimumSize(600, 150)
        vbox = QVBoxLayout()
        vbox.addWidget(QLabel(_("Address") + ': ' + address))
        vbox.addWidget(QLabel(_("Script type") + ': ' + xtype))
        vbox.addWidget(QLabel(_("Private key") + ':'))
        keys_e = ShowQRTextEdit(text=pk)
        keys_e.addCopyButton(self.app)
        vbox.addWidget(keys_e)
        # if redeem_script:
        #     vbox.addWidget(QLabel(_("Redeem Script") + ':'))
        #     rds_e = ShowQRTextEdit(text=redeem_script)
        #     rds_e.addCopyButton(self.app)
        #     vbox.addWidget(rds_e)
        vbox.addLayout(Buttons(CloseButton(d)))
        d.setLayout(vbox)
        d.exec_()

    msg_sign = _("Signing with an address actually means signing with the corresponding "
                "private key, and verifying with the corresponding public key. The "
                "address you have entered does not have a unique public key, so these "
                "operations cannot be performed.") + '\n\n' + \
               _('The operation is undefined. Not just in Electrum-NMC, but in general.')

    @protected
    def do_sign(self, address, message, signature, password):
        address  = address.text().strip()
        message = message.toPlainText().strip()
        if not bitcoin.is_address(address):
            self.show_message(_('Invalid Namecoin address.'))
            return
        if self.wallet.is_watching_only():
            self.show_message(_('This is a watching-only wallet.'))
            return
        if not self.wallet.is_mine(address):
            self.show_message(_('Address not in wallet.'))
            return
        txin_type = self.wallet.get_txin_type(address)
        if txin_type not in ['p2pkh', 'p2wpkh', 'p2wpkh-p2sh']:
            self.show_message(_('Cannot sign messages with this type of address:') + \
                              ' ' + txin_type + '\n\n' + self.msg_sign)
            return
        task = partial(self.wallet.sign_message, address, message, password)

        def show_signed_message(sig):
            try:
                signature.setText(base64.b64encode(sig).decode('ascii'))
            except RuntimeError:
                # (signature) wrapped C/C++ object has been deleted
                pass

        self.wallet.thread.add(task, on_success=show_signed_message)

    def do_verify(self, address, message, signature):
        address  = address.text().strip()
        message = message.toPlainText().strip().encode('utf-8')
        if not bitcoin.is_address(address):
            self.show_message(_('Invalid Namecoin address.'))
            return
        try:
            # This can throw on invalid base64
            sig = base64.b64decode(str(signature.toPlainText()))
            verified = ecc.verify_message_with_address(address, sig, message)
        except Exception as e:
            verified = False
        if verified:
            self.show_message(_("Signature verified"))
        else:
            self.show_error(_("Wrong signature"))

    def sign_verify_message(self, address=''):
        d = WindowModalDialog(self, _('Sign/verify Message'))
        d.setMinimumSize(610, 290)

        layout = QGridLayout(d)

        message_e = QTextEdit()
        message_e.setAcceptRichText(False)
        layout.addWidget(QLabel(_('Message')), 1, 0)
        layout.addWidget(message_e, 1, 1)
        layout.setRowStretch(2,3)

        address_e = QLineEdit()
        address_e.setText(address)
        layout.addWidget(QLabel(_('Address')), 2, 0)
        layout.addWidget(address_e, 2, 1)

        signature_e = QTextEdit()
        signature_e.setAcceptRichText(False)
        layout.addWidget(QLabel(_('Signature')), 3, 0)
        layout.addWidget(signature_e, 3, 1)
        layout.setRowStretch(3,1)

        hbox = QHBoxLayout()

        b = QPushButton(_("Sign"))
        b.clicked.connect(lambda: self.do_sign(address_e, message_e, signature_e))
        hbox.addWidget(b)

        b = QPushButton(_("Verify"))
        b.clicked.connect(lambda: self.do_verify(address_e, message_e, signature_e))
        hbox.addWidget(b)

        b = QPushButton(_("Close"))
        b.clicked.connect(d.accept)
        hbox.addWidget(b)
        layout.addLayout(hbox, 4, 1)
        d.exec_()

    @protected
    def do_decrypt(self, message_e, pubkey_e, encrypted_e, password):
        if self.wallet.is_watching_only():
            self.show_message(_('This is a watching-only wallet.'))
            return
        cyphertext = encrypted_e.toPlainText()
        task = partial(self.wallet.decrypt_message, pubkey_e.text(), cyphertext, password)

        def setText(text):
            try:
                message_e.setText(text.decode('utf-8'))
            except RuntimeError:
                # (message_e) wrapped C/C++ object has been deleted
                pass

        self.wallet.thread.add(task, on_success=setText)

    def do_encrypt(self, message_e, pubkey_e, encrypted_e):
        message = message_e.toPlainText()
        message = message.encode('utf-8')
        try:
            public_key = ecc.ECPubkey(bfh(pubkey_e.text()))
        except BaseException as e:
            self.logger.exception('Invalid Public key')
            self.show_warning(_('Invalid Public key'))
            return
        encrypted = public_key.encrypt_message(message)
        encrypted_e.setText(encrypted.decode('ascii'))

    def encrypt_message(self, address=''):
        d = WindowModalDialog(self, _('Encrypt/decrypt Message'))
        d.setMinimumSize(610, 490)

        layout = QGridLayout(d)

        message_e = QTextEdit()
        message_e.setAcceptRichText(False)
        layout.addWidget(QLabel(_('Message')), 1, 0)
        layout.addWidget(message_e, 1, 1)
        layout.setRowStretch(2,3)

        pubkey_e = QLineEdit()
        if address:
            pubkey = self.wallet.get_public_key(address)
            pubkey_e.setText(pubkey)
        layout.addWidget(QLabel(_('Public key')), 2, 0)
        layout.addWidget(pubkey_e, 2, 1)

        encrypted_e = QTextEdit()
        encrypted_e.setAcceptRichText(False)
        layout.addWidget(QLabel(_('Encrypted')), 3, 0)
        layout.addWidget(encrypted_e, 3, 1)
        layout.setRowStretch(3,1)

        hbox = QHBoxLayout()
        b = QPushButton(_("Encrypt"))
        b.clicked.connect(lambda: self.do_encrypt(message_e, pubkey_e, encrypted_e))
        hbox.addWidget(b)

        b = QPushButton(_("Decrypt"))
        b.clicked.connect(lambda: self.do_decrypt(message_e, pubkey_e, encrypted_e))
        hbox.addWidget(b)

        b = QPushButton(_("Close"))
        b.clicked.connect(d.accept)
        hbox.addWidget(b)

        layout.addLayout(hbox, 4, 1)
        d.exec_()

    def password_dialog(self, msg=None, parent=None):
        from .password_dialog import PasswordDialog
        parent = parent or self
        d = PasswordDialog(parent, msg)
        return d.run()

    def tx_from_text(self, data: Union[str, bytes]) -> Union[None, 'PartialTransaction', 'Transaction']:
        from electrum.transaction import tx_from_any
        try:
            return tx_from_any(data)
        except BaseException as e:
            self.show_critical(_("Electrum-NMC was unable to parse your transaction") + ":\n" + repr(e))
            return

    def import_channel_backup(self, encrypted: str):
        if not self.question('Import channel backup?'):
            return
        try:
            self.wallet.lnbackups.import_channel_backup(encrypted)
        except Exception as e:
            self.show_error("failed to import backup" + '\n' + str(e))
            return

    def read_tx_from_qrcode(self):
        from electrum import qrscanner
        try:
            data = qrscanner.scan_barcode(self.config.get_video_device())
        except BaseException as e:
            self.show_error(repr(e))
            return
        if not data:
            return
        # if the user scanned a bitcoin URI
        if str(data).startswith("namecoin:"):
            self.pay_to_URI(data)
            return
        if data.startswith('channel_backup:'):
            self.import_channel_backup(data)
            return
        # else if the user scanned an offline signed tx
        tx = self.tx_from_text(data)
        if not tx:
            return
        self.show_transaction(tx)

    def read_tx_from_file(self) -> Optional[Transaction]:
        fileName = self.getOpenFileName(_("Select your transaction file"),
                                        TRANSACTION_FILE_EXTENSION_FILTER_ANY)
        if not fileName:
            return
        try:
            with open(fileName, "rb") as f:
                file_content = f.read()  # type: Union[str, bytes]
        except (ValueError, IOError, os.error) as reason:
            self.show_critical(_("Electrum-NMC was unable to open your transaction file") + "\n" + str(reason),
                               title=_("Unable to read file or no transaction found"))
            return
        return self.tx_from_text(file_content)

    def do_process_from_text(self):
        text = text_dialog(self, _('Input raw transaction'), _("Transaction:"), _("Load transaction"))
        if not text:
            return
        tx = self.tx_from_text(text)
        if tx:
            self.show_transaction(tx)

    def do_process_from_text_channel_backup(self):
        text = text_dialog(self, _('Input channel backup'), _("Channel Backup:"), _("Load backup"))
        if not text:
            return
        if text.startswith('channel_backup:'):
            self.import_channel_backup(text)

    def do_process_from_file(self):
        tx = self.read_tx_from_file()
        if tx:
            self.show_transaction(tx)

    def do_process_from_txid(self):
        from electrum import transaction
        txid, ok = QInputDialog.getText(self, _('Lookup transaction'), _('Transaction ID') + ':')
        if ok and txid:
            txid = str(txid).strip()
            try:
                raw_tx = self.network.run_from_another_thread(
                    self.network.get_transaction(txid, timeout=10))
            except UntrustedServerReturnedError as e:
                self.logger.info(f"Error getting transaction from network: {repr(e)}")
                self.show_message(_("Error getting transaction from network") + ":\n" + e.get_message_for_gui())
                return
            except Exception as e:
                self.show_message(_("Error getting transaction from network") + ":\n" + repr(e))
                return
            else:
                tx = transaction.Transaction(raw_tx)
                self.show_transaction(tx)

    @protected
    def export_privkeys_dialog(self, password):
        if self.wallet.is_watching_only():
            self.show_message(_("This is a watching-only wallet"))
            return

        if isinstance(self.wallet, Multisig_Wallet):
            self.show_message(_('WARNING: This is a multi-signature wallet.') + '\n' +
                              _('It cannot be "backed up" by simply exporting these private keys.'))

        d = WindowModalDialog(self, _('Private keys'))
        d.setMinimumSize(980, 300)
        vbox = QVBoxLayout(d)

        msg = "%s\n%s\n%s" % (_("WARNING: ALL your private keys are secret."),
                              _("Exposing a single private key can compromise your entire wallet!"),
                              _("In particular, DO NOT use 'redeem private key' services proposed by third parties."))
        vbox.addWidget(QLabel(msg))

        e = QTextEdit()
        e.setReadOnly(True)
        vbox.addWidget(e)

        defaultname = 'electrum-nmc-private-keys.csv'
        select_msg = _('Select file to export your private keys to')
        hbox, filename_e, csv_button = filename_field(self, self.config, defaultname, select_msg)
        vbox.addLayout(hbox)

        b = OkButton(d, _('Export'))
        b.setEnabled(False)
        vbox.addLayout(Buttons(CancelButton(d), b))

        private_keys = {}
        addresses = self.wallet.get_addresses()
        done = False
        cancelled = False
        def privkeys_thread():
            for addr in addresses:
                time.sleep(0.1)
                if done or cancelled:
                    break
                privkey = self.wallet.export_private_key(addr, password)
                private_keys[addr] = privkey
                self.computing_privkeys_signal.emit()
            if not cancelled:
                self.computing_privkeys_signal.disconnect()
                self.show_privkeys_signal.emit()

        def show_privkeys():
            s = "\n".join( map( lambda x: x[0] + "\t"+ x[1], private_keys.items()))
            e.setText(s)
            b.setEnabled(True)
            self.show_privkeys_signal.disconnect()
            nonlocal done
            done = True

        def on_dialog_closed(*args):
            nonlocal done
            nonlocal cancelled
            if not done:
                cancelled = True
                self.computing_privkeys_signal.disconnect()
                self.show_privkeys_signal.disconnect()

        self.computing_privkeys_signal.connect(lambda: e.setText("Please wait... %d/%d"%(len(private_keys),len(addresses))))
        self.show_privkeys_signal.connect(show_privkeys)
        d.finished.connect(on_dialog_closed)
        threading.Thread(target=privkeys_thread).start()

        if not d.exec_():
            done = True
            return

        filename = filename_e.text()
        if not filename:
            return

        try:
            self.do_export_privkeys(filename, private_keys, csv_button.isChecked())
        except (IOError, os.error) as reason:
            txt = "\n".join([
                _("Electrum-NMC was unable to produce a private key-export."),
                str(reason)
            ])
            self.show_critical(txt, title=_("Unable to create csv"))

        except Exception as e:
            self.show_message(repr(e))
            return

        self.show_message(_("Private keys exported."))

    def do_export_privkeys(self, fileName, pklist, is_csv):
        with open(fileName, "w+") as f:
            os.chmod(fileName, 0o600)
            if is_csv:
                transaction = csv.writer(f)
                transaction.writerow(["address", "private_key"])
                for addr, pk in pklist.items():
                    transaction.writerow(["%34s"%addr,pk])
            else:
                f.write(json.dumps(pklist, indent = 4))

    def do_import_labels(self):
        def on_import():
            self.need_update.set()
        import_meta_gui(self, _('labels'), self.wallet.import_labels, on_import)

    def do_export_labels(self):
        export_meta_gui(self, _('labels'), self.wallet.export_labels)

    def import_invoices(self):
        import_meta_gui(self, _('invoices'), self.wallet.import_invoices, self.invoice_list.update)

    def export_invoices(self):
        export_meta_gui(self, _('invoices'), self.wallet.export_invoices)

    def import_requests(self):
        import_meta_gui(self, _('requests'), self.wallet.import_requests, self.request_list.update)

    def export_requests(self):
        export_meta_gui(self, _('requests'), self.wallet.export_requests)

    def import_contacts(self):
        import_meta_gui(self, _('contacts'), self.contacts.import_file, self.contact_list.update)

    def export_contacts(self):
        export_meta_gui(self, _('contacts'), self.contacts.export_file)


    def sweep_key_dialog(self):
        d = WindowModalDialog(self, title=_('Sweep private keys'))
        d.setMinimumSize(600, 300)
        vbox = QVBoxLayout(d)
        hbox_top = QHBoxLayout()
        hbox_top.addWidget(QLabel(_("Enter private keys:")))
        hbox_top.addWidget(InfoButton(WIF_HELP_TEXT), alignment=Qt.AlignRight)
        vbox.addLayout(hbox_top)
        keys_e = ScanQRTextEdit(allow_multi=True)
        keys_e.setTabChangesFocus(True)
        vbox.addWidget(keys_e)

        addresses = self.wallet.get_unused_addresses()
        if not addresses:
            try:
                addresses = self.wallet.get_receiving_addresses()
            except AttributeError:
                addresses = self.wallet.get_addresses()
        h, address_e = address_field(addresses)
        vbox.addLayout(h)

        vbox.addStretch(1)
        button = OkButton(d, _('Sweep'))
        vbox.addLayout(Buttons(CancelButton(d), button))
        button.setEnabled(False)

        def get_address():
            addr = str(address_e.text()).strip()
            if bitcoin.is_address(addr):
                return addr

        def get_pk(*, raise_on_error=False):
            text = str(keys_e.toPlainText())
            return keystore.get_private_keys(text, raise_on_error=raise_on_error)

        def on_edit():
            valid_privkeys = False
            try:
                valid_privkeys = get_pk(raise_on_error=True) is not None
            except Exception as e:
                button.setToolTip(f'{_("Error")}: {repr(e)}')
            else:
                button.setToolTip('')
            button.setEnabled(get_address() is not None and valid_privkeys)
        on_address = lambda text: address_e.setStyleSheet((ColorScheme.DEFAULT if get_address() else ColorScheme.RED).as_stylesheet())
        keys_e.textChanged.connect(on_edit)
        address_e.textChanged.connect(on_edit)
        address_e.textChanged.connect(on_address)
        on_address(str(address_e.text()))
        if not d.exec_():
            return
        # user pressed "sweep"
        addr = get_address()
        try:
            self.wallet.check_address_for_corruption(addr)
        except InternalAddressCorruption as e:
            self.show_error(str(e))
            raise
        privkeys = get_pk()

        def on_success(result):
            coins, keypairs = result
            outputs = [PartialTxOutput.from_address_and_value(addr, value='!')]
            self.warn_if_watching_only()
            self.pay_onchain_dialog(coins, outputs, external_keypairs=keypairs)
        def on_failure(exc_info):
            self.on_error(exc_info)
        msg = _('Preparing sweep transaction...')
        task = lambda: self.network.run_from_another_thread(
            sweep_preparations(privkeys, self.network))
        WaitingDialog(self, msg, task, on_success, on_failure)

    def _do_import(self, title, header_layout, func):
        text = text_dialog(self, title, header_layout, _('Import'), allow_multi=True)
        if not text:
            return
        keys = str(text).split()
        good_inputs, bad_inputs = func(keys)
        if good_inputs:
            msg = '\n'.join(good_inputs[:10])
            if len(good_inputs) > 10: msg += '\n...'
            self.show_message(_("The following addresses were added")
                              + f' ({len(good_inputs)}):\n' + msg)
        if bad_inputs:
            msg = "\n".join(f"{key[:10]}... ({msg})" for key, msg in bad_inputs[:10])
            if len(bad_inputs) > 10: msg += '\n...'
            self.show_error(_("The following inputs could not be imported")
                            + f' ({len(bad_inputs)}):\n' + msg)
        self.address_list.update()
        self.history_list.update()

    def import_addresses(self):
        if not self.wallet.can_import_address():
            return
        title, msg = _('Import addresses'), _("Enter addresses")+':'
        self._do_import(title, msg, self.wallet.import_addresses)

    @protected
    def do_import_privkey(self, password):
        if not self.wallet.can_import_privkey():
            return
        title = _('Import private keys')
        header_layout = QHBoxLayout()
        header_layout.addWidget(QLabel(_("Enter private keys")+':'))
        header_layout.addWidget(InfoButton(WIF_HELP_TEXT), alignment=Qt.AlignRight)
        self._do_import(title, header_layout, lambda x: self.wallet.import_private_keys(x, password))

    def update_fiat(self):
        b = self.fx and self.fx.is_enabled()
        self.fiat_send_e.setVisible(b)
        self.fiat_receive_e.setVisible(b)
        self.history_list.update()
        self.address_list.refresh_headers()
        self.address_list.update()
        self.update_status()

    def settings_dialog(self):
        from .settings_dialog import SettingsDialog
        d = SettingsDialog(self, self.config)
        self.alias_received_signal.connect(d.set_alias_color)
        d.exec_()
        self.alias_received_signal.disconnect(d.set_alias_color)
        if self.fx:
            self.fx.trigger_update()
        run_hook('close_settings_dialog')
        if d.need_restart:
            self.show_warning(_('Please restart Electrum-NMC to activate the new GUI settings'), title=_('Success'))

    def closeEvent(self, event):
        # It seems in some rare cases this closeEvent() is called twice
        if not self.cleaned_up:
            self.cleaned_up = True
            self.clean_up()
        event.accept()

    def clean_up(self):
        self.wallet.thread.stop()
        util.unregister_callback(self.on_network)
        self.config.set_key("is_maximized", self.isMaximized())
        if not self.isMaximized():
            g = self.geometry()
            self.wallet.db.put("winpos-qt", [g.left(),g.top(),
                                                  g.width(),g.height()])
        self.wallet.db.put("qt-console-history", self.console.history[-50:])
        if self.qr_window:
            self.qr_window.close()
        self.close_wallet()

        self.gui_object.timer.timeout.disconnect(self.timer_actions)
        self.gui_object.close_window(self)

    def plugins_dialog(self):
        self.pluginsdialog = d = WindowModalDialog(self, _('Electrum-NMC Plugins'))

        plugins = self.gui_object.plugins

        vbox = QVBoxLayout(d)

        # plugins
        scroll = QScrollArea()
        scroll.setEnabled(True)
        scroll.setWidgetResizable(True)
        scroll.setMinimumSize(400,250)
        vbox.addWidget(scroll)

        w = QWidget()
        scroll.setWidget(w)
        w.setMinimumHeight(plugins.count() * 35)

        grid = QGridLayout()
        grid.setColumnStretch(0,1)
        w.setLayout(grid)

        settings_widgets = {}

        def enable_settings_widget(p: Optional['BasePlugin'], name: str, i: int):
            widget = settings_widgets.get(name)  # type: Optional[QWidget]
            if widget and not p:
                # plugin got disabled, rm widget
                grid.removeWidget(widget)
                widget.setParent(None)
                settings_widgets.pop(name)
            elif widget is None and p and p.requires_settings() and p.is_enabled():
                # plugin got enabled, add widget
                widget = settings_widgets[name] = p.settings_widget(d)
                grid.addWidget(widget, i, 1)

        def do_toggle(cb, name, i):
            p = plugins.toggle(name)
            cb.setChecked(bool(p))
            enable_settings_widget(p, name, i)
            # note: all enabled plugins will receive this hook:
            run_hook('init_qt', self.gui_object)

        for i, descr in enumerate(plugins.descriptions.values()):
            full_name = descr['__name__']
            prefix, _separator, name = full_name.rpartition('.')
            p = plugins.get(name)
            if descr.get('registers_keystore'):
                continue
            try:
                cb = QCheckBox(descr['fullname'])
                plugin_is_loaded = p is not None
                cb_enabled = (not plugin_is_loaded and plugins.is_available(name, self.wallet)
                              or plugin_is_loaded and p.can_user_disable())
                cb.setEnabled(cb_enabled)
                cb.setChecked(plugin_is_loaded and p.is_enabled())
                grid.addWidget(cb, i, 0)
                enable_settings_widget(p, name, i)
                cb.clicked.connect(partial(do_toggle, cb, name, i))
                msg = descr['description']
                if descr.get('requires'):
                    msg += '\n\n' + _('Requires') + ':\n' + '\n'.join(map(lambda x: x[1], descr.get('requires')))
                grid.addWidget(HelpButton(msg), i, 2)
            except Exception:
                self.logger.exception(f"cannot display plugin {name}")
        grid.setRowStretch(len(plugins.descriptions.values()), 1)
        vbox.addLayout(Buttons(CloseButton(d)))
        d.exec_()

    def cpfp(self, parent_tx: Transaction, new_tx: PartialTransaction) -> None:
        total_size = parent_tx.estimated_size() + new_tx.estimated_size()
        parent_txid = parent_tx.txid()
        assert parent_txid
        parent_fee = self.wallet.get_tx_fee(parent_txid)
        if parent_fee is None:
            self.show_error(_("Can't CPFP: unknown fee for parent transaction."))
            return
        d = WindowModalDialog(self, _('Child Pays for Parent'))
        vbox = QVBoxLayout(d)
        msg = (
            "A CPFP is a transaction that sends an unconfirmed output back to "
            "yourself, with a high fee. The goal is to have miners confirm "
            "the parent transaction in order to get the fee attached to the "
            "child transaction.")
        vbox.addWidget(WWLabel(_(msg)))
        msg2 = ("The proposed fee is computed using your "
            "fee/kB settings, applied to the total size of both child and "
            "parent transactions. After you broadcast a CPFP transaction, "
            "it is normal to see a new unconfirmed transaction in your history.")
        vbox.addWidget(WWLabel(_(msg2)))
        grid = QGridLayout()
        grid.addWidget(QLabel(_('Total size') + ':'), 0, 0)
        grid.addWidget(QLabel('%d bytes'% total_size), 0, 1)
        max_fee = new_tx.output_value()
        grid.addWidget(QLabel(_('Input amount') + ':'), 1, 0)
        grid.addWidget(QLabel(self.format_amount(max_fee) + ' ' + self.base_unit()), 1, 1)
        output_amount = QLabel('')
        grid.addWidget(QLabel(_('Output amount') + ':'), 2, 0)
        grid.addWidget(output_amount, 2, 1)
        fee_e = BTCAmountEdit(self.get_decimal_point)
        # FIXME with dyn fees, without estimates, there are all kinds of crashes here
        combined_fee = QLabel('')
        combined_feerate = QLabel('')
        def on_fee_edit(x):
            fee_for_child = fee_e.get_amount()
            if fee_for_child is None:
                return
            out_amt = max_fee - fee_for_child
            out_amt_str = (self.format_amount(out_amt) + ' ' + self.base_unit()) if out_amt else ''
            output_amount.setText(out_amt_str)
            comb_fee = parent_fee + fee_for_child
            comb_fee_str = (self.format_amount(comb_fee) + ' ' + self.base_unit()) if comb_fee else ''
            combined_fee.setText(comb_fee_str)
            comb_feerate = comb_fee / total_size * 1000
            comb_feerate_str = self.format_fee_rate(comb_feerate) if comb_feerate else ''
            combined_feerate.setText(comb_feerate_str)
        fee_e.textChanged.connect(on_fee_edit)
        def get_child_fee_from_total_feerate(fee_per_kb):
            fee = fee_per_kb * total_size / 1000 - parent_fee
            fee = min(max_fee, fee)
            fee = max(total_size, fee)  # pay at least 1 sat/byte for combined size
            return fee
        suggested_feerate = self.config.fee_per_kb()
        if suggested_feerate is None:
            self.show_error(f'''{_("Can't CPFP'")}: {_('Dynamic fee estimates not available')}''')
            return
        fee = get_child_fee_from_total_feerate(suggested_feerate)
        fee_e.setAmount(fee)
        grid.addWidget(QLabel(_('Fee for child') + ':'), 3, 0)
        grid.addWidget(fee_e, 3, 1)
        def on_rate(dyn, pos, fee_rate):
            fee = get_child_fee_from_total_feerate(fee_rate)
            fee_e.setAmount(fee)
        fee_slider = FeeSlider(self, self.config, on_rate)
        fee_combo = FeeComboBox(fee_slider)
        fee_slider.update()
        grid.addWidget(fee_slider, 4, 1)
        grid.addWidget(fee_combo, 4, 2)
        grid.addWidget(QLabel(_('Total fee') + ':'), 5, 0)
        grid.addWidget(combined_fee, 5, 1)
        grid.addWidget(QLabel(_('Total feerate') + ':'), 6, 0)
        grid.addWidget(combined_feerate, 6, 1)
        vbox.addLayout(grid)
        vbox.addLayout(Buttons(CancelButton(d), OkButton(d)))
        if not d.exec_():
            return
        fee = fee_e.get_amount()
        if fee is None:
            return  # fee left empty, treat is as "cancel"
        if fee > max_fee:
            self.show_error(_('Max fee exceeded'))
            return
        new_tx = self.wallet.cpfp(parent_tx, fee)
        new_tx.set_rbf(True)
        self.show_transaction(new_tx)

    def bump_fee_dialog(self, tx: Transaction):
        txid = tx.txid()
        assert txid
        fee = self.wallet.get_tx_fee(txid)
        if fee is None:
            self.show_error(_("Can't bump fee: unknown fee for original transaction."))
            return
        tx_label = self.wallet.get_label_for_txid(txid)
        tx_size = tx.estimated_size()
        old_fee_rate = fee / tx_size  # sat/vbyte
        d = WindowModalDialog(self, _('Bump Fee'))
        vbox = QVBoxLayout(d)
        vbox.addWidget(WWLabel(_("Increase your transaction's fee to improve its position in mempool.")))

        grid = QGridLayout()
        grid.addWidget(QLabel(_('Current Fee') + ':'), 0, 0)
        grid.addWidget(QLabel(self.format_amount(fee) + ' ' + self.base_unit()), 0, 1)
        grid.addWidget(QLabel(_('Current Fee rate') + ':'), 1, 0)
        grid.addWidget(QLabel(self.format_fee_rate(1000 * old_fee_rate)), 1, 1)

        grid.addWidget(QLabel(_('New Fee rate') + ':'), 2, 0)
        def on_textedit_rate():
            fee_slider.deactivate()
        feerate_e = FeerateEdit(lambda: 0)
        feerate_e.setAmount(max(old_fee_rate * 1.5, old_fee_rate + 1))
        feerate_e.textEdited.connect(on_textedit_rate)
        grid.addWidget(feerate_e, 2, 1)

        def on_slider_rate(dyn, pos, fee_rate):
            fee_slider.activate()
            if fee_rate is not None:
                feerate_e.setAmount(fee_rate / 1000)
        fee_slider = FeeSlider(self, self.config, on_slider_rate)
        fee_combo = FeeComboBox(fee_slider)
        fee_slider.deactivate()
        grid.addWidget(fee_slider, 3, 1)
        grid.addWidget(fee_combo, 3, 2)

        vbox.addLayout(grid)
        cb = QCheckBox(_('Final'))
        vbox.addWidget(cb)
        vbox.addLayout(Buttons(CancelButton(d), OkButton(d)))
        if not d.exec_():
            return
        is_final = cb.isChecked()
        new_fee_rate = feerate_e.get_amount()
        try:
            new_tx = self.wallet.bump_fee(tx=tx, new_fee_rate=new_fee_rate, coins=self.get_coins())
        except CannotBumpFee as e:
            self.show_error(str(e))
            return
        if is_final:
            new_tx.set_rbf(False)
        self.show_transaction(new_tx, tx_desc=tx_label)

    def dscancel_dialog(self, tx: Transaction):
        txid = tx.txid()
        assert txid
        fee = self.wallet.get_tx_fee(txid)
        if fee is None:
            self.show_error(_('Cannot cancel transaction') + ': ' + _('unknown fee for original transaction'))
            return
        tx_size = tx.estimated_size()
        old_fee_rate = fee / tx_size  # sat/vbyte
        d = WindowModalDialog(self, _('Cancel transaction'))
        vbox = QVBoxLayout(d)
        vbox.addWidget(WWLabel(_("Cancel an unconfirmed RBF transaction by double-spending "
                                 "its inputs back to your wallet with a higher fee.")))

        grid = QGridLayout()
        grid.addWidget(QLabel(_('Current Fee') + ':'), 0, 0)
        grid.addWidget(QLabel(self.format_amount(fee) + ' ' + self.base_unit()), 0, 1)
        grid.addWidget(QLabel(_('Current Fee rate') + ':'), 1, 0)
        grid.addWidget(QLabel(self.format_fee_rate(1000 * old_fee_rate)), 1, 1)

        grid.addWidget(QLabel(_('New Fee rate') + ':'), 2, 0)
        def on_textedit_rate():
            fee_slider.deactivate()
        feerate_e = FeerateEdit(lambda: 0)
        feerate_e.setAmount(max(old_fee_rate * 1.5, old_fee_rate + 1))
        feerate_e.textEdited.connect(on_textedit_rate)
        grid.addWidget(feerate_e, 2, 1)

        def on_slider_rate(dyn, pos, fee_rate):
            fee_slider.activate()
            if fee_rate is not None:
                feerate_e.setAmount(fee_rate / 1000)
        fee_slider = FeeSlider(self, self.config, on_slider_rate)
        fee_combo = FeeComboBox(fee_slider)
        fee_slider.deactivate()
        grid.addWidget(fee_slider, 3, 1)
        grid.addWidget(fee_combo, 3, 2)

        vbox.addLayout(grid)
        vbox.addLayout(Buttons(CancelButton(d), OkButton(d)))
        if not d.exec_():
            return
        new_fee_rate = feerate_e.get_amount()
        try:
            new_tx = self.wallet.dscancel(tx=tx, new_fee_rate=new_fee_rate)
        except CannotDoubleSpendTx as e:
            self.show_error(str(e))
            return
        self.show_transaction(new_tx)

    def save_transaction_into_wallet(self, tx: Transaction):
        win = self.top_level_window()
        try:
            if not self.wallet.add_transaction(tx):
                win.show_error(_("Transaction could not be saved.") + "\n" +
                               _("It conflicts with current history."))
                return False
        except AddTransactionException as e:
            win.show_error(e)
            return False
        else:
            self.wallet.save_db()
            # need to update at least: history_list, utxo_list, address_list
            self.need_update.set()
            msg = (_("Transaction added to wallet history.") + '\n\n' +
                   _("Note: this is an offline transaction, if you want the network "
                     "to see it, you need to broadcast it."))
            win.msg_box(QPixmap(icon_path("offline_tx.png")), None, _('Success'), msg)
            return True

    def show_cert_mismatch_error(self):
        if self.showing_cert_mismatch_error:
            return
        self.showing_cert_mismatch_error = True
        self.show_critical(title=_("Certificate mismatch"),
                           msg=_("The SSL certificate provided by the main server did not match the fingerprint passed in with the --serverfingerprint option.") + "\n\n" +
                               _("Electrum-NMC will now exit."))
        self.showing_cert_mismatch_error = False
        self.close()

    def create_buy_names_tab(self):
        w = QWidget()
        self.buy_names_ui = Ui_BuyNamesPage()
        self.buy_names_ui.setupUi(w)

        # TODO: allow hex names
        self.buy_names_new_name_lineedit = self.buy_names_ui.registerName
        self.buy_names_new_name_lineedit.textChanged.connect(self.update_buy_names_preview)

        self.buy_names_value_ascii = ''

        self.buy_names_preview_label = self.buy_names_ui.previewLabel

        self.buy_names_check_name_availability_button = self.buy_names_ui.checkNameButton
        self.buy_names_check_name_availability_button.clicked.connect(self.check_name_availability)

        self.buy_names_status_label = self.buy_names_ui.statusLabel

        self.buy_names_register_button = self.buy_names_ui.registerNameButton
        self.buy_names_register_button.clicked.connect(self.register_new_name)
        self.buy_names_register_button.hide()

        self.buy_names_buy_button = self.buy_names_ui.buyNameButton
        self.buy_names_buy_button.clicked.connect(self.buy_name)
        self.buy_names_buy_button.hide()

        return w

    def update_buy_names_preview(self):
        # TODO: handle non-ASCII encodings
        identifier = self.buy_names_new_name_lineedit.text().encode('ascii')
        identifier_formatted = format_name_identifier(identifier)
        self.buy_names_preview_label.setText(_("Name to register: ") + identifier_formatted)

        self.buy_names_status_label.setText("")
        self.buy_names_register_button.hide()
        self.buy_names_buy_button.hide()

    def check_name_availability(self):
        # TODO: handle non-ASCII encodings
        identifier_ascii = self.buy_names_new_name_lineedit.text()
        identifier = identifier_ascii.encode('ascii')

        identifier_formatted = format_name_identifier(identifier)

        name_list = self.console.namespace.get('name_list')
        name_show = self.console.namespace.get('name_show')

        self.buy_names_value_ascii = ''

        name_exists = True
        name_pending_mine = False
        name_snipe_pending_mine = False
        name_pending_unverified = False
        name_valid = True
        name_mine = False
        name_mine_unverified = False
        chain_syncing = False
        try:
            # First we try looking up the name in the local wallet via
            # name_list.
            name_list_result = name_list(identifier=identifier_ascii, name_encoding="ascii", value_encoding="ascii", wallet=self.wallet)
            for name_list_item in name_list_result:
                # We should only have 0 or 1 items.
                if not name_list_item["expired"] and name_list_item["ismine"]:
                    # Name item purports to be active and mine.
                    self.buy_names_value_ascii = name_list_item["value"]
                    chain_height = self.network.get_local_height()
                    mature_in = name_new_mature_in(name_list_item["height"], chain_height)
                    if mature_in is not None and mature_in <= 0:
                        # Name has at least 12 confirmations, we can confirm
                        # that it's mine.
                        name_mine = True
                    else:
                        # Name has under 12 confirmations, we can't verify it.
                        name_mine_unverified = True

            # Then we check the transaction broadcast queue.
            for txid in self.wallet.db.queued_transactions:
                queue_item = self.wallet.db.queued_transactions[txid]
                tx_hex = queue_item["tx"]
                tx = Transaction(tx_hex)
                # Search for a name output with a matching identifier
                for o in tx.outputs():
                    if o.name_op is None:
                        continue
                    if "name" not in o.name_op:
                        continue
                    if o.name_op["name"] != identifier:
                        continue
                    # At this point we found a matching identifier.  Now we
                    # check the send conditions.
                    send_when = queue_item["sendWhen"]
                    trigger_depth = send_when["confirmations"]
                    if trigger_depth == 12:
                        # This is a typical registration queued transaction.
                        name_pending_mine = True
                    if trigger_depth == constants.net.NAME_EXPIRATION + 1:
                        # This is a snipe registration queued transaction.
                        name_snipe_pending_mine = True

            # If the name doesn't show up in the local wallet, or if the local
            # UNO has under 12 confirmations, then we do a lookup operation via
            # name_show.
            if not name_mine and not name_pending_mine and not name_snipe_pending_mine:
                name_show_result = name_show(identifier_ascii, wallet=self.wallet)
                self.buy_names_value_ascii = name_show_result["value"]
                name_mine = name_show_result["ismine"]
        except commands.NameUnconfirmedError:
            name_pending_unverified = True
        except commands.NameNotFoundError:
            name_exists = False
        except commands.NotSynchronizedException:
            chain_syncing = True
        except util.BitcoinException:
            # This happens if the name identifier exceeded the 255-byte limit.
            name_valid = False
        except commands.NameSemiExpiredError:
            # TODO: Check "ismine"
            pass
        except BestEffortRequestFailed as e:
            msg = repr(e)
            self.show_error(msg)
            return
        except MerkleVerificationFailure:
            # Merkle proof from ElectrumX was invalid
            self.buy_names_register_button.hide()
            self.buy_names_buy_button.hide()
            self.buy_names_status_label.setText(_("Merkle verification failure while checking name availability.  If this persists, try switching servers."))
            return

        if chain_syncing:
            self.buy_names_register_button.hide()
            self.buy_names_buy_button.hide()
            self.buy_names_status_label.setText(_("The blockchain is still syncing; please wait and then try again."))
        elif not name_valid:
            self.buy_names_register_button.hide()
            self.buy_names_buy_button.hide()
            self.buy_names_status_label.setText(_("That name is invalid (probably exceeded the 255-byte limit) and therefore cannot be registered."))
        elif name_mine:
            self.buy_names_register_button.hide()
            self.buy_names_buy_button.hide()
            self.buy_names_status_label.setText(_("You already own ") + identifier_formatted + _("!"))
        elif name_pending_mine:
            self.buy_names_register_button.hide()
            self.buy_names_buy_button.hide()
            self.buy_names_status_label.setText(_("You already have a registration pending for ") + identifier_formatted + _("!"))
        elif name_snipe_pending_mine:
            self.buy_names_register_button.hide()
            self.buy_names_buy_button.show()
            self.buy_names_status_label.setText(_("You already have a snipe pending for ") + identifier_formatted + _("!  Your snipe will be broadcast if/when the name expires.  You might be able to buy the name from the current owner."))
        elif name_exists and not name_pending_unverified:
            self.buy_names_register_button.hide()
            self.buy_names_buy_button.show()
            self.buy_names_status_label.setText(identifier_formatted + _(" is already registered.  You might be able to buy the name from the current owner."))
        elif name_pending_unverified:
            self.buy_names_register_button.show()
            self.buy_names_buy_button.show()
            if name_mine_unverified:
                self.buy_names_status_label.setText(_("The server reports that you already registered ") + identifier_formatted + _(" in approximately the past 2 hours, but Electrum-NMC couldn't verify this.  If you believe the server is wrong, you can try to register it or buy it from the current owner, but you may forfeit the name registration fee."))
            else:
                self.buy_names_status_label.setText(_("The server reports that someone else already registered ") + identifier_formatted + _(" in approximately the past 2 hours, but Electrum-NMC couldn't verify this.  You might be able to buy the name from the current owner.  If you believe the server is wrong, you can try to register it, but you may forfeit the name registration fee."))
        else:
            self.buy_names_register_button.show()
            self.buy_names_buy_button.hide()
            self.buy_names_status_label.setText(identifier_formatted + _(" is available to register!"))

    def register_new_name(self):
        # TODO: handle non-ASCII encodings
        identifier_ascii = self.buy_names_new_name_lineedit.text()
        identifier = identifier_ascii.encode('ascii')

        initial_value = b''

        show_configure_name(identifier, initial_value, self, True)

    def buy_name(self):
        # TODO: handle non-ASCII encodings
        identifier_ascii = self.buy_names_new_name_lineedit.text()
        identifier = identifier_ascii.encode('ascii')

        # TODO: use existing value
        initial_value = self.buy_names_value_ascii.encode('ascii')

        show_trade_name(identifier, initial_value, self, buy=True)

    def create_names_tab(self):
        w = QWidget()
        self.names_ui = Ui_ManageNamesPage()
        self.names_ui.setupUi(w)

        # List of names
        from .uno_list import UNOList
        self.names_uno_list = l = UNOList(self)
        old_uno_list = self.names_ui.verticalLayout.replaceWidget(self.names_ui.tableView, self.names_uno_list)
        self.names_ui.tableView = self.names_uno_list
        old_uno_list.widget().setParent(None)

        self.names_configure_button = self.names_ui.configureNameButton
        self.names_configure_button.clicked.connect(l.configure_selected_item)
        self.names_renew_button = self.names_ui.renewNameButton
        self.names_renew_button.clicked.connect(l.renew_selected_items)
        self.names_sell_button = self.names_ui.sellNameButton
        self.names_sell_button.clicked.connect(l.sell_selected_item)

        l.selectionModel().selectionChanged.connect(self.update_name_buttons_enabled)

        self.update_name_buttons_enabled()

        return w

    def update_name_buttons_enabled(self):
        selected = self.names_uno_list.selected_in_column(0)
        if not selected or len(selected) == 0:
            self.names_configure_button.setDisabled(True)
            self.names_configure_button.setToolTip(_('Change the value of the selected name or transfer ownership (you must select a name first)'))
            self.names_renew_button.setDisabled(True)
            self.names_renew_button.setToolTip(_('Renew the selected names with their current values (nothing will happen for names updated in the last 12 blocks) (you must select at least 1 name first)'))
            self.names_sell_button.setDisabled(True)
            self.names_sell_button.setToolTip(_('Create a Sell Offer or redeem a Buy Offer (you must select a name first)'))
        elif len(selected) == 1:
            self.names_configure_button.setEnabled(True)
            self.names_configure_button.setToolTip(_('Change the value of the selected name or transfer ownership'))
            self.names_renew_button.setEnabled(True)
            self.names_renew_button.setToolTip(_('Renew the selected names with their current values (nothing will happen for names updated in the last 12 blocks)'))
            self.names_sell_button.setEnabled(True)
            self.names_sell_button.setToolTip(_('Create a Sell Offer or redeem a Buy Offer'))
        elif len(selected) > 1:
            self.names_configure_button.setDisabled(True)
            self.names_configure_button.setToolTip(_('Change the value of the selected name or transfer ownership (you must only select a single name)'))
            self.names_renew_button.setEnabled(True)
            self.names_renew_button.setToolTip(_('Renew the selected names with their current values (nothing will happen for names updated in the last 12 blocks)'))
            self.names_sell_button.setDisabled(True)
            self.names_sell_button.setToolTip(_('Create a Sell Offer or redeem a Buy Offer (you must only select a single name)'))

    def update_queued_transactions(self):
        updatequeuedtransactions = self.console.namespace.get('updatequeuedtransactions')
        status, msg = updatequeuedtransactions(wallet=self.wallet)
        if not status:
            self.show_error(_("Error broadcasting the following queued transactions (you'll need to manually broadcast them): ") + str(msg))
