states

void SwitchboardUnit::change_online_state(const OnlineState new_state)
{
    const OnlineState old_state = online;
    bool same = false;
    switch (old_state) {
    case OnlineState::online: {
        switch (new_state) {
        case OnlineState::online: {
            same = true;
            break; }
        case OnlineState::offline: {
            emit online_offline_transition();
            break; }
        case OnlineState::unknown: {
            emit online_unknown_transition();
            break; }
        }
        break; }
    case OnlineState::offline: {
        switch (new_state) {
        case OnlineState::online: {
            emit offline_online_transition();
            break; }
        case OnlineState::offline: {
            same = true;
            break; }
        case OnlineState::unknown: {
            emit offline_unknown_transition();
            break; }
        }
        break; }
    case OnlineState::unknown: {
        switch (new_state) {
        case OnlineState::online: {
            emit unknown_online_transition();
            break; }
        case OnlineState::offline: {
            emit unknown_offline_transition();
            break; }
        case OnlineState::unknown: {
            same = true;
            break; }
        }
        break; }
    }
    if (same) {
        emit warning(
                    "void SwitchboardUnit::change_online_state(OnlineState new_state)"
                    "\nold_state == new_state == "
                    + QString::number(static_cast<qint32>(old_state)));
    }
    else {
        online = new_state;
    }
    switch (online) {
    case OnlineState::online: {
        emit is_online();
        break; }
    case OnlineState::offline: {
        emit is_offline();
        break; }
    case OnlineState::unknown: {
        emit is_in_unknown_online_state();
        break; }
    }
}