/**
* Convert a QueryGroup object to a query string.
*
* @param QueryGroup $query QueryGroup to convert
*
* @return string
*/
protected function queryGroupToString(QueryGroup $query)
{
$groups = $excludes = [];
foreach ($query->getQueries() as $params) {
// Advanced Search
if ($params instanceof QueryGroup) {
$thisGroup = [];
// Process each search group
foreach ($params->getQueries() as $group) {
// Build this group individually as a basic search
$thisGroup[] = $this->abstractQueryToString($group);
}
// Is this an exclusion (NOT) group or a normal group?
if ($params->isNegated()) {
$excludes[] = join(" OR ", $thisGroup);
} else {
$groups[] = join(" " . $params->getOperator() . " ", $thisGroup);
}
} else {
// Basic Search
$groups[] = $this->queryToString($params);
}
}
// Put our advanced search together
$queryStr = '';
if (count($groups) > 0) {
$queryStr .= "(" . join(") " . $query->getOperator() . " (", $groups) . ")";
}
// and concatenate exclusion after that
if (count($excludes) > 0) {
$queryStr .= " NOT ((" . join(") OR (", $excludes) . "))";
}
return $queryStr;
}
