sub get_inbox {
    my ($self, %param) = @_;
    my $limit   = $param{limit}       || DEFAULT_LIMIT;
    my $mode    = $param{mode}        || MESSAGES_INBOX;
    my $view    = $param{view}        || MESSAGES_INBOX;

    my $query = {};
    $query->{mark}   = $param{mark} ? 'true' : 'false';
    $query->{sr_detail} = $param{sr_detail} if $param{sr_detail};
    $query->{before} = $param{before} if $param{before};
    $query->{after}  = $param{after}  if $param{after};
    [... more code snipped ...]
}