text: #!/usr/bin/env python
  #
  # Electrum - lightweight Bitcoin client
  # Copyright (C) 2015 Thomas Voegtlin
  #
  # 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.
  from electrum.i18n import _
  from electrum.util import format_time
  from electrum.paymentrequest import PR_UNPAID
  from .util import *
  
  
  class InvoiceList(MyTreeWidget):
      filter_columns = [0, 1, 2, 3]  # Date, Requestor, Description, Amount
  
      def __init__(self, parent):
          MyTreeWidget.__init__(self, parent, self.create_menu, [_('Expires'), _('Requestor'), _('Description'), _('Amount'), _('Status')], 2)
          self.setSortingEnabled(True)
          self.header().setSectionResizeMode(1, QHeaderView.Interactive)
          self.setColumnWidth(1, 200)
  
      def on_update(self):
          inv_list = self.parent.invoices.unpaid_invoices()
          self.clear()
          for pr in inv_list:
              key = pr.get_id()
              status = self.parent.invoices.get_status(key)
              requestor = pr.get_requestor()
              exp = pr.get_expiration_date()
              date_str = format_time(exp) if exp else _('Never')
              item = QTreeWidgetItem([date_str, requestor, pr.memo, self.parent.format_amount(pr.get_amount(), whitespaces=True), pr_tooltips.get(status,'')])
              item.setIcon(4, read_QIcon(pr_icons.get(status)))
              item.setData(0, Qt.UserRole, key)
              item.setFont(1, QFont(MONOSPACE_FONT))
              item.setFont(3, QFont(MONOSPACE_FONT))
              self.addTopLevelItem(item)
          self.setCurrentItem(self.topLevelItem(0))
          self.setVisible(len(inv_list))
          self.parent.invoices_label.setVisible(len(inv_list))
  
      def import_invoices(self):
          import_meta_gui(self.parent, _('invoices'), self.parent.invoices.import_file, self.on_update)
  
      def export_invoices(self):
          export_meta_gui(self.parent, _('invoices'), self.parent.invoices.export_file)
  
      def create_menu(self, position):
          menu = QMenu()
          item = self.itemAt(position)
          if not item:
              return
          key = item.data(0, Qt.UserRole)
          column = self.currentColumn()
          column_title = self.headerItem().text(column)
          column_data = item.text(column)
          pr = self.parent.invoices.get(key)
          status = self.parent.invoices.get_status(key)
          if column_data:
              menu.addAction(_("Copy %s")%column_title, lambda: self.parent.app.clipboard().setText(column_data))
          menu.addAction(_("Details"), lambda: self.parent.show_invoice(key))
          if status == PR_UNPAID:
              menu.addAction(_("Pay Now"), lambda: self.parent.do_pay_invoice(key))
          menu.addAction(_("Delete"), lambda: self.parent.delete_invoice(key))
          menu.exec_(self.viewport().mapToGlobal(position))
  