/**
* Returns query from context.
*
* @throws QueryParserException
* @return SearchQueryInterface
*/
public function getQuery()
{
/**
* We treat each level of an expression as a boolean expression in
* a Disjunctive Normal Form
*
* AND operator has higher precedence than OR
*
* Thus logical query is a disjunction of one or more conjunctions of
* one or more query entries
*/
$expressionParser = new BooleanExpressionParser($this->_defaultLogicalOperator, $this->_higherPriorityLogicalOperator);
try {
foreach ($this->_entries as $entry) {
if ($entry instanceof QueryEntryInterface) {
$expressionParser->processLiteral($entry);
} else {
switch ($entry) {
case QueryToken::TYPE_AND_OPERATOR:
$expressionParser->processOperator(BooleanExpressionParser::IN_AND_OPERATOR);
break;
case QueryToken::TYPE_OR_OPERATOR:
$expressionParser->processOperator(BooleanExpressionParser::IN_OR_OPERATOR);
break;
case QueryToken::TYPE_NOT_OPERATOR:
$expressionParser->processOperator(BooleanExpressionParser::IN_NOT_OPERATOR);
break;
default:
throw new \UnexpectedValueException('Boolean expression error. Unknown operator type.');
}
}
}
$conjunctions = $expressionParser->finishExpression();
} catch (\Exception $e) {
// It's query syntax error message and it should be user friendly. So FSM message is omitted
throw new QueryParserException('Boolean expression error.', 0, $e);
}
// Remove 'only negative' conjunctions
foreach ($conjunctions as $conjunctionId => $conjunction) {
$nonNegativeEntryFound = false;
foreach ($conjunction as $conjunctionEntry) {
if ($conjunctionEntry[1] || $conjunctionEntry[1] === null) {
$nonNegativeEntryFound = true;
break;
}
}
if (!$nonNegativeEntryFound) {
unset($conjunctions[$conjunctionId]);
}
}
$subQueries = [];
$signs = [];
foreach ($conjunctions as $conjunction) {
// Check, if it's a one term conjunction
if (count($conjunction) === 1) {
/** @var QueryEntryInterface $entry */
$entry = $conjunction[0][0];
$subQueries[] = $entry->getQuery();
$signs[end(array_keys($subQueries))] = $conjunction[0][1];
} else {
$subQuery = new Boolean();
foreach ($conjunction as $conjunctionEntry) {
$entry = $conjunctionEntry[0];
$subQuery->addSubquery($entry->getQuery(), $conjunctionEntry[1]);
}
$subQueries[] = $subQuery;
}
}
if (count($subQueries) == 1) {
return $subQueries[0];
}
$query = new Boolean();
foreach ($subQueries as $key => $subQuery) {
$query->addSubquery($subQuery, array_key_exists($key, $signs) ? $signs[$key] : ($this->_higherPriorityLogicalOperator === QueryParser::OPERATOR_OR ? true : null));
}
return $query;
}
/**
* Add one query to another.
*
* @param SearchQueryInterface $toQuery
* @param FieldQueryInterface $query
* @param bool|null $sign
* @return bool|SearchQueryInterface
*/
protected static function addQuery(SearchQueryInterface $toQuery, FieldQueryInterface $query, $sign = true)
{
if ($toQuery instanceof BooleanQueryInterface) {
$subQueries = $toQuery->getSubQueries();
$signs = $toQuery->getSigns();
foreach ($subQueries as $key => $subQuery) {
if ($newQuery = self::addQuery($subQuery, $query, $sign)) {
$subQueries[$key] = $newQuery;
$toQuery->setSubQueries($subQueries, $signs);
return $toQuery;
}
}
} elseif ($toQuery instanceof FieldQueryInterface) {
$equal = $toQuery->equals($query);
if ($equal === 0) {
$newQuery = new Boolean();
$newQuery->setSubQueries([$toQuery, $query], [$sign, $sign]);
return $newQuery;
} elseif ($equal === 1) {
return $toQuery;
}
}
return false;
}