CallId Scheduler::acceptRequest( const IncidenceBase::Ptr &incidence,
                                 ScheduleMessage::Status status,
                                 const QString &email )
{
  Incidence::Ptr inc = incidence.staticCast<Incidence>() ;
  if ( !inc ) {
    kWarning() << "Accept what?";
    return -1;
  }

  const CallId callId = ++d->mLatestCallId;
  ResultCode resultCode = ResultCodeSuccess;
  QString errorMessage;

  if ( inc->type() == IncidenceBase::TypeFreeBusy ) {
    emitOperationFinished( callId, ResultCodeSuccess, QString() );
    // reply to this request is handled in korganizer's incomingdialog
    return callId;
  }

  const Incidence::List existingIncidences = d->mCalendar->incidencesFromSchedulingID( inc->uid() );
  kDebug() << "status=" << Stringify::scheduleMessageStatus( status ) //krazy:exclude=kdebug
           << ": found " << existingIncidences.count()
           << " incidences with schedulingID " << inc->schedulingID()
           << "; uid was = " << inc->uid();

  if ( existingIncidences.isEmpty() ) {
    // Perfectly normal if the incidence doesn't exist. This is probably
    // a new invitation.
    kDebug() << "incidence not found; calendar = " << d->mCalendar.data()
             << "; incidence count = " << d->mCalendar->incidences().count();
  }
  Incidence::List::ConstIterator incit = existingIncidences.begin();
  for ( ; incit != existingIncidences.end() ; ++incit ) {
    Incidence::Ptr existingIncidence = *incit;
    kDebug() << "Considering this found event ("
             << ( existingIncidence->isReadOnly() ? "readonly" : "readwrite" )
             << ") :" << d->mFormat->toString( existingIncidence );
    // If it's readonly, we can't possible update it.
    if ( existingIncidence->isReadOnly() ) {
      continue;
    }
    if ( existingIncidence->revision() <= inc->revision() ) {
      // The new incidence might be an update for the found one
      bool isUpdate = true;
      // Code for new invitations:
      // If you think we could check the value of "status" to be RequestNew:  we can't.
      // It comes from a similar check inside libical, where the event is compared to
      // other events in the calendar. But if we have another version of the event around
      // (e.g. shared folder for a group), the status could be RequestNew, Obsolete or Updated.
      kDebug() << "looking in " << existingIncidence->uid() << "'s attendees";
      // This is supposed to be a new request, not an update - however we want to update
      // the existing one to handle the "clicking more than once on the invitation" case.
      // So check the attendee status of the attendee.
      const Attendee::List attendees = existingIncidence->attendees();
      Attendee::List::ConstIterator ait;
      for ( ait = attendees.begin(); ait != attendees.end(); ++ait ) {
        if( (*ait)->email() == email && (*ait)->status() == Attendee::NeedsAction ) {
          // This incidence wasn't created by me - it's probably in a shared folder
          // and meant for someone else, ignore it.
          kDebug() << "ignoring "
                   << existingIncidence->uid() << " since I'm still NeedsAction there";
          isUpdate = false;
          break;
        }
      }
      if ( isUpdate ) {
        if ( existingIncidence->revision() == inc->revision() &&
             existingIncidence->lastModified() > inc->lastModified() ) {
          // This isn't an update - the found incidence was modified more recently
          deleteTransaction( existingIncidence->uid() );
          errorMessage = QLatin1String( "This isn't an update - "
                                        "the found incidence was modified more recently" );
          kDebug() << errorMessage;
          emitOperationFinished( callId, ResultCodeNotUpdate, errorMessage );

          return callId;
        }
        kDebug() << "replacing existing incidence " << existingIncidence->uid();

        bool emitResult = true;
        const QString oldUid = existingIncidence->uid();
        if ( existingIncidence->type() != inc->type() ) {
          errorMessage = QLatin1String( "Cannot assign two different incidence types" );
          resultCode = ResultCodeDifferentIncidenceTypes;
        } else {
          IncidenceBase *existingIncidenceBase = existingIncidence.data();
          IncidenceBase *incBase = inc.data();
          *existingIncidenceBase = *incBase;
          existingIncidence->setSchedulingID( inc->uid(), oldUid );

          Akonadi::Item item = d->mCalendar->itemForIncidenceUid( oldUid );
          item.setPayload<Incidence::Ptr>( existingIncidence );
          if ( item.isValid() ) {
            const int changeId = d->mChanger->modifyIncidence( item );

            if ( changeId >= 0 ) {
              d->mCallIdByChangeId.insert( changeId, callId );
              emitResult = false; // will be emitted in the job result's slot.
            } else {
              resultCode = ResultCodeErrorUpdatingIncidence;
              errorMessage = QLatin1String( "Error while trying to update the incidence" );
            }
          } else {
            resultCode = ResultCodeIncidenceNotFound;
            errorMessage = QLatin1String( "Couldn't find incidence in calendar" );
          }
        }

        if ( emitResult ) {
          deleteTransaction( incidence->uid() );
          emitOperationFinished( callId, resultCode, errorMessage );
        }
        return callId;
      }
    } else {
      // This isn't an update - the found incidence has a bigger revision number

      deleteTransaction( incidence->uid() );

      errorMessage = QLatin1String( "This isn't an update - "
                                    "the found incidence has a bigger revision number" );
      kDebug() << errorMessage;
      emitOperationFinished( callId, ResultCodeNotUpdate, errorMessage );

      return callId;
    }
  }

  // Move the uid to be the schedulingID and make a unique UID
  inc->setSchedulingID( inc->uid(), CalFormat::createUniqueId() );
  // notify the user in case this is an update and we didn't find the to-be-updated incidence
  if ( existingIncidences.count() == 0 && inc->revision() > 0 ) {
    KMessageBox::information(
      0,
      i18nc( "@info",
             "<para>You accepted an invitation update, but an earlier version of the "
             "item could not be found in your calendar.</para>"
             "<para>This may have occurred because:<list>"
             "<item>the organizer did not include you in the original invitation</item>"
             "<item>you did not accept the original invitation yet</item>"
             "<item>you deleted the original invitation from your calendar</item>"
             "<item>you no longer have access to the calendar containing the invitation</item>"
             "</list></para>"
             "<para>This is not a problem, but we thought you should know.</para>" ),
      i18nc( "@title", "Cannot find invitation to be updated" ), "AcceptCantFindIncidence" );
  }
  kDebug() << "Storing new incidence with scheduling uid=" << inc->schedulingID()
           << " and uid=" << inc->uid();
  const int changeId = d->mChanger->createIncidence( inc );

  if ( changeId > 0 ) {
    d->mCallIdByChangeId[changeId] = callId;
  } else {
    emitOperationFinished( callId, ResultCodeErrorCreatingIncidence,
                           QLatin1String( "Error creating incidence" ) );
  }

  return callId;
}
CallId Scheduler::acceptPublish( const IncidenceBase::Ptr &newIncBase,
                                 ScheduleMessage::Status status,
                                 iTIPMethod method )
{
  if ( newIncBase->type() == IncidenceBase::TypeFreeBusy ) {
    return acceptFreeBusy( newIncBase, method );
  }

  const CallId callId = ++d->mLatestCallId;

  ResultCode resultCode = ResultCodeSuccess;
  QString errorMessage;

  kDebug() << "status=" << Stringify::scheduleMessageStatus( status ); //krazy:exclude=kdebug

  bool emitResult = true;

  Incidence::Ptr newInc = newIncBase.staticCast<Incidence>() ;
  Incidence::Ptr calInc = d->mCalendar->incidence( newIncBase->uid() );
  switch ( status ) {
    case ScheduleMessage::Unknown:
    case ScheduleMessage::PublishNew:
    case ScheduleMessage::PublishUpdate:
      if ( calInc && newInc ) {
        if ( ( newInc->revision() > calInc->revision() ) ||
             ( newInc->revision() == calInc->revision() &&
               newInc->lastModified() > calInc->lastModified() ) ) {
          const QString oldUid = calInc->uid();

          if ( calInc->type() != newInc->type() ) {
            kError() << "assigning different incidence types";
            resultCode = ResultCodeDifferentIncidenceTypes;
            errorMessage = QLatin1String( "Cannot assign two different incidence types" );
          } else {
            IncidenceBase *ci = calInc.data();
            IncidenceBase *ni = newInc.data();
            *ci = *ni;
            calInc->setSchedulingID( newInc->uid(), oldUid );

            Akonadi::Item item = d->mCalendar->itemForIncidenceUid( calInc->uid() );
            item.setPayload<Incidence::Ptr>( calInc );

            if ( item.isValid() ) {
              const int changeId = d->mChanger->modifyIncidence( item );

              if ( changeId >= 0 ) {
                d->mCallIdByChangeId.insert( changeId, callId );
                emitResult = false; // will be emitted in the job result's slot.
              } else {
                resultCode = ResultCodeErrorUpdatingIncidence;
                errorMessage = QLatin1String( "Error while trying to update the incidence" );
              }
            } else {
              resultCode = ResultCodeIncidenceNotFound;
              errorMessage = QLatin1String( "Couldn't find incidence in calendar" );
            }
          }
        } else {
          resultCode = ResultCodeNewIncidenceTooOld;
          errorMessage = QLatin1String( "A newer existing incidence already exists" );
        }
      } else {
        resultCode = ResultCodeInvalidIncidence;
        errorMessage = QLatin1String( "Incidence is invalid" );
      }
      break;
    case ScheduleMessage::Obsolete:
      // Success
      break;
    default:
      resultCode = ResultCodeUnknownStatus;
      errorMessage = QLatin1String( "Unhandled ScheduleMessage status" );
      break;
  }

  if ( emitResult ) {
    deleteTransaction( newIncBase->uid() );
    // Delayed signal, the caller must know this CallId first.
    emitOperationFinished( callId, resultCode, errorMessage );
  }

  return callId;
}