text: #!/usr/bin/env python
  #
  # Electrum - lightweight Bitcoin client
  #
  # 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 html
  from typing import TYPE_CHECKING, Optional, Set
  
  from PyQt5.QtCore import QObject
  import PyQt5.QtCore as QtCore
  from PyQt5.QtWidgets import (QWidget, QLabel, QPushButton, QTextEdit,
                               QMessageBox, QHBoxLayout, QVBoxLayout)
  
  from electrum.i18n import _
  from electrum.base_crash_reporter import BaseCrashReporter
  from electrum.logging import Logger
  from electrum import constants
  from electrum.network import Network
  
  from .util import MessageBoxMixin, read_QIcon, WaitingDialog
  
  if TYPE_CHECKING:
      from electrum.simple_config import SimpleConfig
      from electrum.wallet import Abstract_Wallet
  
  
  class Exception_Window(BaseCrashReporter, QWidget, MessageBoxMixin, Logger):
      _active_window = None
  
      def __init__(self, config: 'SimpleConfig', exctype, value, tb):
          BaseCrashReporter.__init__(self, exctype, value, tb)
          self.network = Network.get_instance()
          self.config = config
  
          QWidget.__init__(self)
          self.setWindowTitle('Electrum-NMC - ' + _('An Error Occurred'))
          self.setMinimumSize(600, 300)
  
          Logger.__init__(self)
  
          main_box = QVBoxLayout()
  
          heading = QLabel('<h2>' + BaseCrashReporter.CRASH_TITLE + '</h2>')
          main_box.addWidget(heading)
          main_box.addWidget(QLabel(BaseCrashReporter.CRASH_MESSAGE))
  
          main_box.addWidget(QLabel(BaseCrashReporter.REQUEST_HELP_MESSAGE))
  
          collapse_info = QPushButton(_("Show report contents"))
          collapse_info.clicked.connect(
              lambda: self.msg_box(QMessageBox.NoIcon,
                                   self, _("Report contents"), self.get_report_string(),
                                   rich_text=True))
  
          main_box.addWidget(collapse_info)
  
          main_box.addWidget(QLabel(BaseCrashReporter.DESCRIBE_ERROR_MESSAGE))
  
          self.description_textfield = QTextEdit()
          self.description_textfield.setFixedHeight(50)
          self.description_textfield.setPlaceholderText(_("Do not enter sensitive/private information here. "
                                                          "The report will be visible on the public issue tracker."))
          main_box.addWidget(self.description_textfield)
  
          main_box.addWidget(QLabel(BaseCrashReporter.ASK_CONFIRM_SEND))
  
          buttons = QHBoxLayout()
  
          report_button = QPushButton(_('Send Bug Report'))
          report_button.clicked.connect(self.send_report)
          report_button.setIcon(read_QIcon("tab_send.png"))
          buttons.addWidget(report_button)
  
          never_button = QPushButton(_('Never'))
          never_button.clicked.connect(self.show_never)
          buttons.addWidget(never_button)
  
          close_button = QPushButton(_('Not Now'))
          close_button.clicked.connect(self.close)
          buttons.addWidget(close_button)
  
          main_box.addLayout(buttons)
  
          self.setLayout(main_box)
          self.show()
  
      def send_report(self):
          def on_success(response):
              # note: 'response' coming from (remote) crash reporter server.
              # It contains a URL to the GitHub issue, so we allow rich text.
              self.show_message(parent=self,
                                title=_("Crash report"),
                                msg=response,
                                rich_text=True)
              self.close()
          def on_failure(exc_info):
              e = exc_info[1]
              self.logger.error('There was a problem with the automatic reporting', exc_info=exc_info)
              self.show_critical(parent=self,
                                 msg=(_('There was a problem with the automatic reporting:') + '<br/>' +
                                      repr(e)[:120] + '<br/><br/>' +
                                      _("Please report this issue manually") +
                                      f' <a href="{constants.GIT_REPO_ISSUES_URL}">on GitHub</a>.'),
                                 rich_text=True)
  
          proxy = self.network.proxy
          task = lambda: BaseCrashReporter.send_report(self, self.network.asyncio_loop, proxy)
          msg = _('Sending crash report...')
          WaitingDialog(self, msg, task, on_success, on_failure)
  
      def on_close(self):
          Exception_Window._active_window = None
          self.close()
  
      def show_never(self):
          self.config.set_key(BaseCrashReporter.config_key, False)
          self.close()
  
      def closeEvent(self, event):
          self.on_close()
          event.accept()
  
      def get_user_description(self):
          return self.description_textfield.toPlainText()
  
      def get_wallet_type(self):
          wallet_types = Exception_Hook._INSTANCE.wallet_types_seen
          return ",".join(wallet_types)
  
      def _get_traceback_str(self) -> str:
          # The msg_box that shows the report uses rich_text=True, so
          # if traceback contains special HTML characters, e.g. '<',
          # they need to be escaped to avoid formatting issues.
          traceback_str = super()._get_traceback_str()
          return html.escape(traceback_str)
  
  
  def _show_window(*args):
      if not Exception_Window._active_window:
          Exception_Window._active_window = Exception_Window(*args)
  
  
  class Exception_Hook(QObject, Logger):
      _report_exception = QtCore.pyqtSignal(object, object, object, object)
  
      _INSTANCE = None  # type: Optional[Exception_Hook]  # singleton
  
      def __init__(self, *, config: 'SimpleConfig'):
          QObject.__init__(self)
          Logger.__init__(self)
          assert self._INSTANCE is None, "Exception_Hook is supposed to be a singleton"
          self.config = config
          self.wallet_types_seen = set()  # type: Set[str]
  
          sys.excepthook = self.handler
          self._report_exception.connect(_show_window)
  
      @classmethod
      def maybe_setup(cls, *, config: 'SimpleConfig', wallet: 'Abstract_Wallet') -> None:
          if not config.get(BaseCrashReporter.config_key, default=True):
              return
          if not cls._INSTANCE:
              cls._INSTANCE = Exception_Hook(config=config)
          cls._INSTANCE.wallet_types_seen.add(wallet.wallet_type)
  
      def handler(self, *exc_info):
          self.logger.error('exception caught by crash reporter', exc_info=exc_info)
          self._report_exception.emit(self.config, *exc_info)
  