text: import json
  from collections import defaultdict
  from decimal import Decimal
  
  import bleach
  import dateutil.parser
  import pytz
  from django.dispatch import receiver
  from django.urls import reverse
  from django.utils.formats import date_format
  from django.utils.html import escape
  from django.utils.safestring import mark_safe
  from django.utils.translation import pgettext_lazy, ugettext_lazy as _
  from i18nfield.strings import LazyI18nString
  
  from pretix.base.models import (
      CheckinList, Event, ItemVariation, LogEntry, OrderPosition,
  )
  from pretix.base.signals import logentry_display
  from pretix.base.templatetags.money import money_filter
  
  OVERVIEW_BANLIST = [
      'pretix.plugins.sendmail.order.email.sent'
  ]
  
  
  def _display_order_changed(event: Event, logentry: LogEntry):
      data = json.loads(logentry.data)
  
      text = _('The order has been changed:')
      if logentry.action_type == 'pretix.event.order.changed.item':
          old_item = str(event.items.get(pk=data['old_item']))
          if data['old_variation']:
              old_item += ' - ' + str(ItemVariation.objects.get(item__event=event, pk=data['old_variation']))
          new_item = str(event.items.get(pk=data['new_item']))
          if data['new_variation']:
              new_item += ' - ' + str(ItemVariation.objects.get(item__event=event, pk=data['new_variation']))
          return text + ' ' + _('Position #{posid}: {old_item} ({old_price}) changed '
                                'to {new_item} ({new_price}).').format(
              posid=data.get('positionid', '?'),
              old_item=old_item, new_item=new_item,
              old_price=money_filter(Decimal(data['old_price']), event.currency),
              new_price=money_filter(Decimal(data['new_price']), event.currency),
          )
      elif logentry.action_type == 'pretix.event.order.changed.seat':
          return text + ' ' + _('Position #{posid}: Seat "{old_seat}" changed '
                                'to "{new_seat}".').format(
              posid=data.get('positionid', '?'),
              old_seat=data.get('old_seat'), new_seat=data.get('new_seat'),
          )
      elif logentry.action_type == 'pretix.event.order.changed.subevent':
          old_se = str(event.subevents.get(pk=data['old_subevent']))
          new_se = str(event.subevents.get(pk=data['new_subevent']))
          return text + ' ' + _('Position #{posid}: Event date "{old_event}" ({old_price}) changed '
                                'to "{new_event}" ({new_price}).').format(
              posid=data.get('positionid', '?'),
              old_event=old_se, new_event=new_se,
              old_price=money_filter(Decimal(data['old_price']), event.currency),
              new_price=money_filter(Decimal(data['new_price']), event.currency),
          )
      elif logentry.action_type == 'pretix.event.order.changed.price':
          return text + ' ' + _('Price of position #{posid} changed from {old_price} '
                                'to {new_price}.').format(
              posid=data.get('positionid', '?'),
              old_price=money_filter(Decimal(data['old_price']), event.currency),
              new_price=money_filter(Decimal(data['new_price']), event.currency),
          )
      elif logentry.action_type == 'pretix.event.order.changed.feevalue':
          return text + ' ' + _('A fee was changed from {old_price} to {new_price}.').format(
              old_price=money_filter(Decimal(data['old_price']), event.currency),
              new_price=money_filter(Decimal(data['new_price']), event.currency),
          )
      elif logentry.action_type == 'pretix.event.order.changed.cancelfee':
          return text + ' ' + _('A fee of {old_price} was removed.').format(
              old_price=money_filter(Decimal(data['old_price']), event.currency),
          )
      elif logentry.action_type == 'pretix.event.order.changed.cancel':
          old_item = str(event.items.get(pk=data['old_item']))
          if data['old_variation']:
              old_item += ' - ' + str(ItemVariation.objects.get(pk=data['old_variation']))
          return text + ' ' + _('Position #{posid} ({old_item}, {old_price}) canceled.').format(
              posid=data.get('positionid', '?'),
              old_item=old_item,
              old_price=money_filter(Decimal(data['old_price']), event.currency),
          )
      elif logentry.action_type == 'pretix.event.order.changed.add':
          item = str(event.items.get(pk=data['item']))
          if data['variation']:
              item += ' - ' + str(ItemVariation.objects.get(item__event=event, pk=data['variation']))
          if data['addon_to']:
              addon_to = OrderPosition.objects.get(order__event=event, pk=data['addon_to'])
              return text + ' ' + _('Position #{posid} created: {item} ({price}) as an add-on to '
                                    'position #{addon_to}.').format(
                  posid=data.get('positionid', '?'),
                  item=item, addon_to=addon_to.positionid,
                  price=money_filter(Decimal(data['price']), event.currency),
              )
          else:
              return text + ' ' + _('Position #{posid} created: {item} ({price}).').format(
                  posid=data.get('positionid', '?'),
                  item=item,
                  price=money_filter(Decimal(data['price']), event.currency),
              )
      elif logentry.action_type == 'pretix.event.order.changed.secret':
          return text + ' ' + _('A new secret has been generated for position #{posid}.').format(
              posid=data.get('positionid', '?'),
          )
      elif logentry.action_type == 'pretix.event.order.changed.split':
          old_item = str(event.items.get(pk=data['old_item']))
          if data['old_variation']:
              old_item += ' - ' + str(ItemVariation.objects.get(pk=data['old_variation']))
          url = reverse('control:event.order', kwargs={
              'event': event.slug,
              'organizer': event.organizer.slug,
              'code': data['new_order']
          })
          return mark_safe(escape(text) + ' ' + _('Position #{posid} ({old_item}, {old_price}) split into new order: {order}').format(
              old_item=escape(old_item),
              posid=data.get('positionid', '?'),
              order='<a href="{}">{}</a>'.format(url, data['new_order']),
              old_price=money_filter(Decimal(data['old_price']), event.currency),
          ))
      elif logentry.action_type == 'pretix.event.order.changed.split_from':
          return _('This order has been created by splitting the order {order}').format(
              order=data['original_order'],
          )
  
  
  def _display_checkin(event, logentry):
      data = logentry.parsed_data
  
      show_dt = False
      if 'datetime' in data:
          dt = dateutil.parser.parse(data.get('datetime'))
          show_dt = abs((logentry.datetime - dt).total_seconds()) > 60 or 'forced' in data
          tz = pytz.timezone(event.settings.timezone)
          dt_formatted = date_format(dt.astimezone(tz), "SHORT_DATETIME_FORMAT")
  
      if 'list' in data:
          try:
              checkin_list = event.checkin_lists.get(pk=data.get('list')).name
          except CheckinList.DoesNotExist:
              checkin_list = _("(unknown)")
      else:
          checkin_list = _("(unknown)")
  
      if data.get('first'):
          if show_dt:
              return _('Position #{posid} has been checked in at {datetime} for list "{list}".').format(
                  posid=data.get('positionid'),
                  datetime=dt_formatted,
                  list=checkin_list
              )
          else:
              return _('Position #{posid} has been checked in for list "{list}".').format(
                  posid=data.get('positionid'),
                  list=checkin_list
              )
      else:
          if data.get('forced'):
              return _(
                  'A scan for position #{posid} at {datetime} for list "{list}" has been uploaded even though it has '
                  'been scanned already.'.format(
                      posid=data.get('positionid'),
                      datetime=dt_formatted,
                      list=checkin_list
                  )
              )
          return _(
              'Position #{posid} has been scanned and rejected because it has already been scanned before '
              'on list "{list}".'.format(
                  posid=data.get('positionid'),
                  list=checkin_list
              )
          )
  
  
  @receiver(signal=logentry_display, dispatch_uid="pretixcontrol_logentry_display")
  def pretixcontrol_logentry_display(sender: Event, logentry: LogEntry, **kwargs):
      plains = {
          'pretix.event.comment': _('The event\'s internal comment has been updated.'),
          'pretix.event.order.modified': _('The order details have been changed.'),
          'pretix.event.order.unpaid': _('The order has been marked as unpaid.'),
          'pretix.event.order.secret.changed': _('The order\'s secret has been changed.'),
          'pretix.event.order.expirychanged': _('The order\'s expiry date has been changed.'),
          'pretix.event.order.expired': _('The order has been marked as expired.'),
          'pretix.event.order.paid': _('The order has been marked as paid.'),
          'pretix.event.order.refunded': _('The order has been refunded.'),
          'pretix.event.order.canceled': _('The order has been canceled.'),
          'pretix.event.order.deleted': _('The test mode order {code} has been deleted.'),
          'pretix.event.order.placed': _('The order has been created.'),
          'pretix.event.order.placed.require_approval': _('The order requires approval before it can continue to be processed.'),
          'pretix.event.order.approved': _('The order has been approved.'),
          'pretix.event.order.denied': _('The order has been denied.'),
          'pretix.event.order.contact.changed': _('The email address has been changed from "{old_email}" '
                                                  'to "{new_email}".'),
          'pretix.event.order.locale.changed': _('The order locale has been changed.'),
          'pretix.event.order.invoice.generated': _('The invoice has been generated.'),
          'pretix.event.order.invoice.regenerated': _('The invoice has been regenerated.'),
          'pretix.event.order.invoice.reissued': _('The invoice has been reissued.'),
          'pretix.event.order.comment': _('The order\'s internal comment has been updated.'),
          'pretix.event.order.checkin_attention': _('The order\'s flag to require attention at check-in has been '
                                                    'toggled.'),
          'pretix.event.order.payment.changed': _('A new payment {local_id} has been started instead of the previous one.'),
          'pretix.event.order.email.sent': _('An unidentified type email has been sent.'),
          'pretix.event.order.email.error': _('Sending of an email has failed.'),
          'pretix.event.order.email.attachments.skipped': _('The email has been sent without attachments since they '
                                                            'would have been too large to be likely to arrive.'),
          'pretix.event.order.email.custom_sent': _('A custom email has been sent.'),
          'pretix.event.order.email.download_reminder_sent': _('An email has been sent with a reminder that the ticket '
                                                               'is available for download.'),
          'pretix.event.order.email.expire_warning_sent': _('An email has been sent with a warning that the order is about '
                                                            'to expire.'),
          'pretix.event.order.email.order_canceled': _('An email has been sent to notify the user that the order has been canceled.'),
          'pretix.event.order.email.order_changed': _('An email has been sent to notify the user that the order has been changed.'),
          'pretix.event.order.email.order_free': _('An email has been sent to notify the user that the order has been received.'),
          'pretix.event.order.email.order_paid': _('An email has been sent to notify the user that payment has been received.'),
          'pretix.event.order.email.order_denied': _('An email has been sent to notify the user that the order has been denied.'),
          'pretix.event.order.email.order_approved': _('An email has been sent to notify the user that the order has '
                                                       'been approved.'),
          'pretix.event.order.email.order_placed': _('An email has been sent to notify the user that the order has been received and requires payment.'),
          'pretix.event.order.email.order_placed_require_approval': _('An email has been sent to notify the user that '
                                                                      'the order has been received and requires '
                                                                      'approval.'),
          'pretix.event.order.email.resend': _('An email with a link to the order detail page has been resent to the user.'),
          'pretix.event.order.payment.confirmed': _('Payment {local_id} has been confirmed.'),
          'pretix.event.order.payment.canceled': _('Payment {local_id} has been canceled.'),
          'pretix.event.order.payment.canceled.failed': _('Cancelling payment {local_id} has failed.'),
          'pretix.event.order.payment.started': _('Payment {local_id} has been started.'),
          'pretix.event.order.payment.failed': _('Payment {local_id} has failed.'),
          'pretix.event.order.quotaexceeded': _('The order could not be marked as paid: {message}'),
          'pretix.event.order.overpaid': _('The order has been overpaid.'),
          'pretix.event.order.refund.created': _('Refund {local_id} has been created.'),
          'pretix.event.order.refund.created.externally': _('Refund {local_id} has been created by an external entity.'),
          'pretix.event.order.refund.requested': _('The customer requested you to issue a refund.'),
          'pretix.event.order.refund.done': _('Refund {local_id} has been completed.'),
          'pretix.event.order.refund.canceled': _('Refund {local_id} has been canceled.'),
          'pretix.event.order.refund.failed': _('Refund {local_id} has failed.'),
          'pretix.control.auth.user.created': _('The user has been created.'),
          'pretix.user.settings.2fa.enabled': _('Two-factor authentication has been enabled.'),
          'pretix.user.settings.2fa.disabled': _('Two-factor authentication has been disabled.'),
          'pretix.user.settings.2fa.regenemergency': _('Your two-factor emergency codes have been regenerated.'),
          'pretix.user.settings.2fa.device.added': _('A new two-factor authentication device "{name}" has been added to '
                                                     'your account.'),
          'pretix.user.settings.2fa.device.deleted': _('The two-factor authentication device "{name}" has been removed '
                                                       'from your account.'),
          'pretix.user.settings.notifications.enabled': _('Notifications have been enabled.'),
          'pretix.user.settings.notifications.disabled': _('Notifications have been disabled.'),
          'pretix.user.settings.notifications.changed': _('Your notification settings have been changed.'),
          'pretix.user.anonymized': _('This user has been anonymized.'),
          'pretix.user.oauth.authorized': _('The application "{application_name}" has been authorized to access your '
                                            'account.'),
          'pretix.control.auth.user.forgot_password.mail_sent': _('Password reset mail sent.'),
          'pretix.control.auth.user.forgot_password.recovered': _('The password has been reset.'),
          'pretix.organizer.deleted': _('The organizer "{name}" has been deleted.'),
          'pretix.voucher.added': _('The voucher has been created.'),
          'pretix.voucher.sent': _('The voucher has been sent to {recipient}.'),
          'pretix.voucher.added.waitinglist': _('The voucher has been created and sent to a person on the waiting list.'),
          'pretix.voucher.changed': _('The voucher has been changed.'),
          'pretix.voucher.deleted': _('The voucher has been deleted.'),
          'pretix.voucher.redeemed': _('The voucher has been redeemed in order {order_code}.'),
          'pretix.event.item.added': _('The product has been created.'),
          'pretix.event.item.changed': _('The product has been changed.'),
          'pretix.event.item.deleted': _('The product has been deleted.'),
          'pretix.event.item.variation.added': _('The variation "{value}" has been created.'),
          'pretix.event.item.variation.deleted': _('The variation "{value}" has been deleted.'),
          'pretix.event.item.variation.changed': _('The variation "{value}" has been changed.'),
          'pretix.event.item.addons.added': _('An add-on has been added to this product.'),
          'pretix.event.item.addons.removed': _('An add-on has been removed from this product.'),
          'pretix.event.item.addons.changed': _('An add-on has been changed on this product.'),
          'pretix.event.item.bundles.added': _('A bundled item has been added to this product.'),
          'pretix.event.item.bundles.removed': _('A bundled item has been removed from this product.'),
          'pretix.event.item.bundles.changed': _('A bundled item has been changed on this product.'),
          'pretix.event.quota.added': _('The quota has been added.'),
          'pretix.event.quota.deleted': _('The quota has been deleted.'),
          'pretix.event.quota.changed': _('The quota has been changed.'),
          'pretix.event.quota.closed': _('The quota has closed.'),
          'pretix.event.quota.opened': _('The quota has been re-opened.'),
          'pretix.event.category.added': _('The category has been added.'),
          'pretix.event.category.deleted': _('The category has been deleted.'),
          'pretix.event.category.changed': _('The category has been changed.'),
          'pretix.event.question.added': _('The question has been added.'),
          'pretix.event.question.deleted': _('The question has been deleted.'),
          'pretix.event.question.changed': _('The question has been changed.'),
          'pretix.event.taxrule.added': _('The tax rule has been added.'),
          'pretix.event.taxrule.deleted': _('The tax rule has been deleted.'),
          'pretix.event.taxrule.changed': _('The tax rule has been changed.'),
          'pretix.event.checkinlist.added': _('The check-in list has been added.'),
          'pretix.event.checkinlist.deleted': _('The check-in list has been deleted.'),
          'pretix.event.checkinlist.changed': _('The check-in list has been changed.'),
          'pretix.event.settings': _('The event settings have been changed.'),
          'pretix.event.tickets.settings': _('The ticket download settings have been changed.'),
          'pretix.event.plugins.enabled': _('A plugin has been enabled.'),
          'pretix.event.plugins.disabled': _('A plugin has been disabled.'),
          'pretix.event.live.activated': _('The shop has been taken live.'),
          'pretix.event.live.deactivated': _('The shop has been taken offline.'),
          'pretix.event.testmode.activated': _('The shop has been taken into test mode.'),
          'pretix.event.testmode.deactivated': _('The test mode has been disabled.'),
          'pretix.event.added': _('The event has been created.'),
          'pretix.event.changed': _('The event settings have been changed.'),
          'pretix.event.question.option.added': _('An answer option has been added to the question.'),
          'pretix.event.question.option.deleted': _('An answer option has been removed from the question.'),
          'pretix.event.question.option.changed': _('An answer option has been changed.'),
          'pretix.event.permissions.added': _('A user has been added to the event team.'),
          'pretix.event.permissions.invited': _('A user has been invited to the event team.'),
          'pretix.event.permissions.changed': _('A user\'s permissions have been changed.'),
          'pretix.event.permissions.deleted': _('A user has been removed from the event team.'),
          'pretix.waitinglist.voucher': _('A voucher has been sent to a person on the waiting list.'),
          'pretix.event.orders.waitinglist.deleted': _('An entry has been removed from the waiting list.'),
          'pretix.event.orders.waitinglist.changed': _('An entry has been changed on the waiting list.'),
          'pretix.event.orders.waitinglist.added': _('An entry has been added to the waiting list.'),
          'pretix.team.created': _('The team has been created.'),
          'pretix.team.changed': _('The team settings have been changed.'),
          'pretix.team.deleted': _('The team has been deleted.'),
          'pretix.subevent.deleted': pgettext_lazy('subevent', 'The event date has been deleted.'),
          'pretix.subevent.changed': pgettext_lazy('subevent', 'The event date has been changed.'),
          'pretix.subevent.added': pgettext_lazy('subevent', 'The event date has been created.'),
          'pretix.subevent.quota.added': pgettext_lazy('subevent', 'A quota has been added to the event date.'),
          'pretix.subevent.quota.changed': pgettext_lazy('subevent', 'A quota has been changed on the event date.'),
          'pretix.subevent.quota.deleted': pgettext_lazy('subevent', 'A quota has been removed from the event date.'),
          'pretix.device.created': _('The device has been created.'),
          'pretix.device.changed': _('The device has been changed.'),
          'pretix.device.revoked': _('Access of the device has been revoked.'),
          'pretix.device.initialized': _('The device has been initialized.'),
          'pretix.device.keyroll': _('The access token of the device has been regenerated.'),
          'pretix.device.updated': _('The device has notified the server of an hardware or software update.'),
      }
  
      data = json.loads(logentry.data)
  
      if logentry.action_type.startswith('pretix.event.item.variation'):
          if 'value' not in data:
              # Backwards compatibility
              var = ItemVariation.objects.filter(id=data['id']).first()
              if var:
                  data['value'] = str(var.value)
              else:
                  data['value'] = '?'
          else:
              data['value'] = LazyI18nString(data['value'])
  
      if logentry.action_type in plains:
          data = defaultdict(lambda: '?', data)
          return plains[logentry.action_type].format_map(data)
  
      if logentry.action_type.startswith('pretix.event.order.changed'):
          return _display_order_changed(sender, logentry)
  
      if logentry.action_type.startswith('pretix.event.payment.provider.'):
          return _('The settings of a payment provider have been changed.')
  
      if logentry.action_type.startswith('pretix.event.tickets.provider.'):
          return _('The settings of a ticket output provider have been changed.')
  
      if logentry.action_type == 'pretix.event.order.consent':
          return _('The user confirmed the following message: "{}"').format(
              bleach.clean(logentry.parsed_data.get('msg'), tags=[], strip=True)
          )
  
      if logentry.action_type == 'pretix.event.checkin':
          return _display_checkin(sender, logentry)
  
      if logentry.action_type == 'pretix.control.views.checkin':
          # deprecated
          dt = dateutil.parser.parse(data.get('datetime'))
          tz = pytz.timezone(sender.settings.timezone)
          dt_formatted = date_format(dt.astimezone(tz), "SHORT_DATETIME_FORMAT")
          if 'list' in data:
              try:
                  checkin_list = sender.checkin_lists.get(pk=data.get('list')).name
              except CheckinList.DoesNotExist:
                  checkin_list = _("(unknown)")
          else:
              checkin_list = _("(unknown)")
  
          if data.get('first'):
              return _('Position #{posid} has been checked in manually at {datetime} on list "{list}".').format(
                  posid=data.get('positionid'),
                  datetime=dt_formatted,
                  list=checkin_list,
              )
          return _('Position #{posid} has been checked in again at {datetime} on list "{list}".').format(
              posid=data.get('positionid'),
              datetime=dt_formatted,
              list=checkin_list
          )
  
      if logentry.action_type in ('pretix.control.views.checkin.reverted', 'pretix.event.checkin.reverted'):
          if 'list' in data:
              try:
                  checkin_list = sender.checkin_lists.get(pk=data.get('list')).name
              except CheckinList.DoesNotExist:
                  checkin_list = _("(unknown)")
          else:
              checkin_list = _("(unknown)")
  
          return _('The check-in of position #{posid} on list "{list}" has been reverted.').format(
              posid=data.get('positionid'),
              list=checkin_list,
          )
  
      if logentry.action_type == 'pretix.team.member.added':
          return _('{user} has been added to the team.').format(user=data.get('email'))
  
      if logentry.action_type == 'pretix.team.member.removed':
          return _('{user} has been removed from the team.').format(user=data.get('email'))
  
      if logentry.action_type == 'pretix.team.member.joined':
          return _('{user} has joined the team using the invite sent to {email}.').format(
              user=data.get('email'), email=data.get('invite_email')
          )
  
      if logentry.action_type == 'pretix.team.invite.created':
          return _('{user} has been invited to the team.').format(user=data.get('email'))
  
      if logentry.action_type == 'pretix.team.invite.resent':
          return _('Invite for {user} has been resent.').format(user=data.get('email'))
  
      if logentry.action_type == 'pretix.team.invite.deleted':
          return _('The invite for {user} has been revoked.').format(user=data.get('email'))
  
      if logentry.action_type == 'pretix.team.token.created':
          return _('The token "{name}" has been created.').format(name=data.get('name'))
  
      if logentry.action_type == 'pretix.team.token.deleted':
          return _('The token "{name}" has been revoked.').format(name=data.get('name'))
  
      if logentry.action_type == 'pretix.user.settings.changed':
          text = str(_('Your account settings have been changed.'))
          if 'email' in data:
              text = text + ' ' + str(_('Your email address has been changed to {email}.').format(email=data['email']))
          if 'new_pw' in data:
              text = text + ' ' + str(_('Your password has been changed.'))
          if data.get('is_active') is True:
              text = text + ' ' + str(_('Your account has been enabled.'))
          elif data.get('is_active') is False:
              text = text + ' ' + str(_('Your account has been disabled.'))
          return text
  
      if logentry.action_type == 'pretix.control.auth.user.impersonated':
          return str(_('You impersonated {}.')).format(data['other_email'])
  
      if logentry.action_type == 'pretix.control.auth.user.impersonate_stopped':
          return str(_('You stopped impersonating {}.')).format(data['other_email'])
  