/**
* Generate 'boolean style' query from the context
* 'term1 and term2 or term3 and (<subquery1>) and not (<subquery2>)'
*
* @return Zend_Search_Lucene_Search_Query
* @throws Zend_Search_Lucene
*/
private function _booleanExpressionQuery()
{
/**
* 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
*/
require_once 'Zend/Search/Lucene/Search/BooleanExpressionRecognizer.php';
$expressionRecognizer = new Zend_Search_Lucene_Search_BooleanExpressionRecognizer();
require_once 'Zend/Search/Lucene/Exception.php';
try {
foreach ($this->_entries as $entry) {
if ($entry instanceof Zend_Search_Lucene_Search_QueryEntry) {
$expressionRecognizer->processLiteral($entry);
} else {
switch ($entry) {
case Zend_Search_Lucene_Search_QueryToken::TT_AND_LEXEME:
$expressionRecognizer->processOperator(Zend_Search_Lucene_Search_BooleanExpressionRecognizer::IN_AND_OPERATOR);
break;
case Zend_Search_Lucene_Search_QueryToken::TT_OR_LEXEME:
$expressionRecognizer->processOperator(Zend_Search_Lucene_Search_BooleanExpressionRecognizer::IN_OR_OPERATOR);
break;
case Zend_Search_Lucene_Search_QueryToken::TT_NOT_LEXEME:
$expressionRecognizer->processOperator(Zend_Search_Lucene_Search_BooleanExpressionRecognizer::IN_NOT_OPERATOR);
break;
default:
throw new Zend_Search_Lucene('Boolean expression error. Unknown operator type.');
}
}
}
$conjuctions = $expressionRecognizer->finishExpression();
} catch (Zend_Search_Exception $e) {
// throw new Zend_Search_Lucene_Search_QueryParserException('Boolean expression error. Error message: \'' .
// $e->getMessage() . '\'.' );
// It's query syntax error message and it should be user friendly. So FSM message is omitted
require_once 'Zend/Search/Lucene/Search/QueryParserException.php';
throw new Zend_Search_Lucene_Search_QueryParserException('Boolean expression error.', 0, $e);
}
// Remove 'only negative' conjunctions
foreach ($conjuctions as $conjuctionId => $conjuction) {
$nonNegativeEntryFound = false;
foreach ($conjuction as $conjuctionEntry) {
if ($conjuctionEntry[1]) {
$nonNegativeEntryFound = true;
break;
}
}
if (!$nonNegativeEntryFound) {
unset($conjuctions[$conjuctionId]);
}
}
$subqueries = array();
foreach ($conjuctions as $conjuction) {
// Check, if it's a one term conjuction
if (count($conjuction) == 1) {
$subqueries[] = $conjuction[0][0]->getQuery($this->_encoding);
} else {
require_once 'Zend/Search/Lucene/Search/Query/Boolean.php';
$subquery = new Zend_Search_Lucene_Search_Query_Boolean();
foreach ($conjuction as $conjuctionEntry) {
$subquery->addSubquery($conjuctionEntry[0]->getQuery($this->_encoding), $conjuctionEntry[1]);
}
$subqueries[] = $subquery;
}
}
if (count($subqueries) == 0) {
require_once 'Zend/Search/Lucene/Search/Query/Insignificant.php';
return new Zend_Search_Lucene_Search_Query_Insignificant();
}
if (count($subqueries) == 1) {
return $subqueries[0];
}
require_once 'Zend/Search/Lucene/Search/Query/Boolean.php';
$query = new Zend_Search_Lucene_Search_Query_Boolean();
foreach ($subqueries as $subquery) {
// Non-requirered entry/subquery
$query->addSubquery($subquery);
}
return $query;
}
private function _booleanExpressionQuery()
{
$expressionRecognizer = new Zend_Search_Lucene_Search_BooleanExpressionRecognizer();
try {
foreach ($this->_entries as $entry) {
if ($entry instanceof Zend_Search_Lucene_Search_QueryEntry) {
$expressionRecognizer->processLiteral($entry);
} else {
switch ($entry) {
case Zend_Search_Lucene_Search_QueryToken::TT_AND_LEXEME:
$expressionRecognizer->processOperator(Zend_Search_Lucene_Search_BooleanExpressionRecognizer::IN_AND_OPERATOR);
break;
case Zend_Search_Lucene_Search_QueryToken::TT_OR_LEXEME:
$expressionRecognizer->processOperator(Zend_Search_Lucene_Search_BooleanExpressionRecognizer::IN_OR_OPERATOR);
break;
case Zend_Search_Lucene_Search_QueryToken::TT_NOT_LEXEME:
$expressionRecognizer->processOperator(Zend_Search_Lucene_Search_BooleanExpressionRecognizer::IN_NOT_OPERATOR);
break;
default:
throw new Zend_Search_Lucene('Boolean expression error. Unknown operator type.');
}
}
}
$conjuctions = $expressionRecognizer->finishExpression();
} catch (Zend_Search_Exception $e) {
throw new Zend_Search_Lucene_Search_QueryParserException('Boolean expression error.', 0, $e);
}
foreach ($conjuctions as $conjuctionId => $conjuction) {
$nonNegativeEntryFound = false;
foreach ($conjuction as $conjuctionEntry) {
if ($conjuctionEntry[1]) {
$nonNegativeEntryFound = true;
break;
}
}
if (!$nonNegativeEntryFound) {
unset($conjuctions[$conjuctionId]);
}
}
$subqueries = array();
foreach ($conjuctions as $conjuction) {
if (count($conjuction) == 1) {
$subqueries[] = $conjuction[0][0]->getQuery($this->_encoding);
} else {
$subquery = new Zend_Search_Lucene_Search_Query_Boolean();
foreach ($conjuction as $conjuctionEntry) {
$subquery->addSubquery($conjuctionEntry[0]->getQuery($this->_encoding), $conjuctionEntry[1]);
}
$subqueries[] = $subquery;
}
}
if (count($subqueries) == 0) {
return new Zend_Search_Lucene_Search_Query_Insignificant();
}
if (count($subqueries) == 1) {
return $subqueries[0];
}
$query = new Zend_Search_Lucene_Search_Query_Boolean();
foreach ($subqueries as $subquery) {
$query->addSubquery($subquery);
}
return $query;
}
