protected/modules/zendsearch/vendors/Zend/Search/Lucene/Search/QueryLexer.php

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<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Search_Lucene
 * @subpackage Search
 * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: QueryLexer.php 24593 2012-01-05 20:35:02Z matthew $
 */

/** Zend_Search_Lucene_FSM */
require_once 'Zend/Search/Lucene/FSM.php';

/** Zend_Search_Lucene_Search_QueryParser */
require_once 'Zend/Search/Lucene/Search/QueryToken.php';

/**
 * @category   Zend
 * @package    Zend_Search_Lucene
 * @subpackage Search
 * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Search_Lucene_Search_QueryLexer extends Zend_Search_Lucene_FSM
{
    /** State Machine states */
    const ST_WHITE_SPACE = 0;
    const ST_SYNT_LEXEME = 1;
    const ST_LEXEME = 2;
    const ST_QUOTED_LEXEME = 3;
    const ST_ESCAPED_CHAR = 4;
    const ST_ESCAPED_QCHAR = 5;
    const ST_LEXEME_MODIFIER = 6;
    const ST_NUMBER = 7;
    const ST_MANTISSA = 8;
    const ST_ERROR = 9;

    /** Input symbols */
    const IN_WHITE_SPACE = 0;
    const IN_SYNT_CHAR = 1;
    const IN_LEXEME_MODIFIER = 2;
    const IN_ESCAPE_CHAR = 3;
    const IN_QUOTE = 4;
    const IN_DECIMAL_POINT = 5;
    const IN_ASCII_DIGIT = 6;
    const IN_CHAR = 7;
    const IN_MUTABLE_CHAR = 8;

    const QUERY_WHITE_SPACE_CHARS = " \n\r\t";
    const QUERY_SYNT_CHARS = ':()[]{}!|&';
    const QUERY_MUTABLE_CHARS = '+-';
    const QUERY_DOUBLECHARLEXEME_CHARS = '|&';
    const QUERY_LEXEMEMODIFIER_CHARS = '~^';
    const QUERY_ASCIIDIGITS_CHARS = '0123456789';

    /**
     * List of recognized lexemes
     *
     * @var array
     */
    private $_lexemes;

    /**
     * Query string (array of single- or non single-byte characters)
     *
     * @var array
     */
    private $_queryString;

    /**
     * Current position within a query string
     * Used to create appropriate error messages
     *
     * @var integer
     */
    private $_queryStringPosition;

    /**
     * Recognized part of current lexeme
     *
     * @var string
     */
    private $_currentLexeme;

    public function __construct()
    {
        parent::__construct(
            [
                self::ST_WHITE_SPACE,
                self::ST_SYNT_LEXEME,
                self::ST_LEXEME,
                self::ST_QUOTED_LEXEME,
                self::ST_ESCAPED_CHAR,
                self::ST_ESCAPED_QCHAR,
                self::ST_LEXEME_MODIFIER,
                self::ST_NUMBER,
                self::ST_MANTISSA,
                self::ST_ERROR
            ],
            [
                self::IN_WHITE_SPACE,
                self::IN_SYNT_CHAR,
                self::IN_MUTABLE_CHAR,
                self::IN_LEXEME_MODIFIER,
                self::IN_ESCAPE_CHAR,
                self::IN_QUOTE,
                self::IN_DECIMAL_POINT,
                self::IN_ASCII_DIGIT,
                self::IN_CHAR
            ]
        );

        $lexemeModifierErrorAction = new Zend_Search_Lucene_FSMAction($this, 'lexModifierErrException');
        $quoteWithinLexemeErrorAction = new Zend_Search_Lucene_FSMAction($this, 'quoteWithinLexemeErrException');
        $wrongNumberErrorAction = new Zend_Search_Lucene_FSMAction($this, 'wrongNumberErrException');

        $this->addRules(
            [
                [self::ST_WHITE_SPACE, self::IN_WHITE_SPACE, self::ST_WHITE_SPACE],
                [self::ST_WHITE_SPACE, self::IN_SYNT_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_WHITE_SPACE, self::IN_MUTABLE_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_WHITE_SPACE, self::IN_LEXEME_MODIFIER, self::ST_LEXEME_MODIFIER],
                [self::ST_WHITE_SPACE, self::IN_ESCAPE_CHAR, self::ST_ESCAPED_CHAR],
                [self::ST_WHITE_SPACE, self::IN_QUOTE, self::ST_QUOTED_LEXEME],
                [self::ST_WHITE_SPACE, self::IN_DECIMAL_POINT, self::ST_LEXEME],
                [self::ST_WHITE_SPACE, self::IN_ASCII_DIGIT, self::ST_LEXEME],
                [self::ST_WHITE_SPACE, self::IN_CHAR, self::ST_LEXEME]
            ]
        );
        $this->addRules(
            [
                [self::ST_SYNT_LEXEME, self::IN_WHITE_SPACE, self::ST_WHITE_SPACE],
                [self::ST_SYNT_LEXEME, self::IN_SYNT_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_SYNT_LEXEME, self::IN_MUTABLE_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_SYNT_LEXEME, self::IN_LEXEME_MODIFIER, self::ST_LEXEME_MODIFIER],
                [self::ST_SYNT_LEXEME, self::IN_ESCAPE_CHAR, self::ST_ESCAPED_CHAR],
                [self::ST_SYNT_LEXEME, self::IN_QUOTE, self::ST_QUOTED_LEXEME],
                [self::ST_SYNT_LEXEME, self::IN_DECIMAL_POINT, self::ST_LEXEME],
                [self::ST_SYNT_LEXEME, self::IN_ASCII_DIGIT, self::ST_LEXEME],
                [self::ST_SYNT_LEXEME, self::IN_CHAR, self::ST_LEXEME]
            ]
        );
        $this->addRules(
            [
                [self::ST_LEXEME, self::IN_WHITE_SPACE, self::ST_WHITE_SPACE],
                [self::ST_LEXEME, self::IN_SYNT_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_LEXEME, self::IN_MUTABLE_CHAR, self::ST_LEXEME],
                [self::ST_LEXEME, self::IN_LEXEME_MODIFIER, self::ST_LEXEME_MODIFIER],
                [self::ST_LEXEME, self::IN_ESCAPE_CHAR, self::ST_ESCAPED_CHAR],
                // IN_QUOTE     not allowed
                [self::ST_LEXEME, self::IN_QUOTE, self::ST_ERROR, $quoteWithinLexemeErrorAction],
                [self::ST_LEXEME, self::IN_DECIMAL_POINT, self::ST_LEXEME],
                [self::ST_LEXEME, self::IN_ASCII_DIGIT, self::ST_LEXEME],
                [self::ST_LEXEME, self::IN_CHAR, self::ST_LEXEME]
            ]
        );
        $this->addRules(
            [
                [self::ST_QUOTED_LEXEME, self::IN_WHITE_SPACE, self::ST_QUOTED_LEXEME],
                [self::ST_QUOTED_LEXEME, self::IN_SYNT_CHAR, self::ST_QUOTED_LEXEME],
                [self::ST_QUOTED_LEXEME, self::IN_MUTABLE_CHAR, self::ST_QUOTED_LEXEME],
                [self::ST_QUOTED_LEXEME, self::IN_LEXEME_MODIFIER, self::ST_QUOTED_LEXEME],
                [self::ST_QUOTED_LEXEME, self::IN_ESCAPE_CHAR, self::ST_ESCAPED_QCHAR],
                [self::ST_QUOTED_LEXEME, self::IN_QUOTE, self::ST_WHITE_SPACE],
                [self::ST_QUOTED_LEXEME, self::IN_DECIMAL_POINT, self::ST_QUOTED_LEXEME],
                [self::ST_QUOTED_LEXEME, self::IN_ASCII_DIGIT, self::ST_QUOTED_LEXEME],
                [self::ST_QUOTED_LEXEME, self::IN_CHAR, self::ST_QUOTED_LEXEME]
            ]
        );
        $this->addRules(
            [
                [self::ST_ESCAPED_CHAR, self::IN_WHITE_SPACE, self::ST_LEXEME],
                [self::ST_ESCAPED_CHAR, self::IN_SYNT_CHAR, self::ST_LEXEME],
                [self::ST_ESCAPED_CHAR, self::IN_MUTABLE_CHAR, self::ST_LEXEME],
                [self::ST_ESCAPED_CHAR, self::IN_LEXEME_MODIFIER, self::ST_LEXEME],
                [self::ST_ESCAPED_CHAR, self::IN_ESCAPE_CHAR, self::ST_LEXEME],
                [self::ST_ESCAPED_CHAR, self::IN_QUOTE, self::ST_LEXEME],
                [self::ST_ESCAPED_CHAR, self::IN_DECIMAL_POINT, self::ST_LEXEME],
                [self::ST_ESCAPED_CHAR, self::IN_ASCII_DIGIT, self::ST_LEXEME],
                [self::ST_ESCAPED_CHAR, self::IN_CHAR, self::ST_LEXEME]
            ]
        );
        $this->addRules(
            [
                [self::ST_ESCAPED_QCHAR, self::IN_WHITE_SPACE, self::ST_QUOTED_LEXEME],
                [self::ST_ESCAPED_QCHAR, self::IN_SYNT_CHAR, self::ST_QUOTED_LEXEME],
                [self::ST_ESCAPED_QCHAR, self::IN_MUTABLE_CHAR, self::ST_QUOTED_LEXEME],
                [self::ST_ESCAPED_QCHAR, self::IN_LEXEME_MODIFIER, self::ST_QUOTED_LEXEME],
                [self::ST_ESCAPED_QCHAR, self::IN_ESCAPE_CHAR, self::ST_QUOTED_LEXEME],
                [self::ST_ESCAPED_QCHAR, self::IN_QUOTE, self::ST_QUOTED_LEXEME],
                [self::ST_ESCAPED_QCHAR, self::IN_DECIMAL_POINT, self::ST_QUOTED_LEXEME],
                [self::ST_ESCAPED_QCHAR, self::IN_ASCII_DIGIT, self::ST_QUOTED_LEXEME],
                [self::ST_ESCAPED_QCHAR, self::IN_CHAR, self::ST_QUOTED_LEXEME]
            ]
        );
        $this->addRules(
            [
                [self::ST_LEXEME_MODIFIER, self::IN_WHITE_SPACE, self::ST_WHITE_SPACE],
                [self::ST_LEXEME_MODIFIER, self::IN_SYNT_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_LEXEME_MODIFIER, self::IN_MUTABLE_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_LEXEME_MODIFIER, self::IN_LEXEME_MODIFIER, self::ST_LEXEME_MODIFIER],
                // IN_ESCAPE_CHAR       not allowed
                [self::ST_LEXEME_MODIFIER, self::IN_ESCAPE_CHAR, self::ST_ERROR, $lexemeModifierErrorAction],
                // IN_QUOTE             not allowed
                [self::ST_LEXEME_MODIFIER, self::IN_QUOTE, self::ST_ERROR, $lexemeModifierErrorAction],
                [self::ST_LEXEME_MODIFIER, self::IN_DECIMAL_POINT, self::ST_MANTISSA],
                [self::ST_LEXEME_MODIFIER, self::IN_ASCII_DIGIT, self::ST_NUMBER],
                // IN_CHAR              not allowed
                [self::ST_LEXEME_MODIFIER, self::IN_CHAR, self::ST_ERROR, $lexemeModifierErrorAction],
            ]
        );
        $this->addRules(
            [
                [self::ST_NUMBER, self::IN_WHITE_SPACE, self::ST_WHITE_SPACE],
                [self::ST_NUMBER, self::IN_SYNT_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_NUMBER, self::IN_MUTABLE_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_NUMBER, self::IN_LEXEME_MODIFIER, self::ST_LEXEME_MODIFIER],
                // IN_ESCAPE_CHAR       not allowed
                [self::ST_NUMBER, self::IN_ESCAPE_CHAR, self::ST_ERROR, $wrongNumberErrorAction],
                // IN_QUOTE             not allowed
                [self::ST_NUMBER, self::IN_QUOTE, self::ST_ERROR, $wrongNumberErrorAction],
                [self::ST_NUMBER, self::IN_DECIMAL_POINT, self::ST_MANTISSA],
                [self::ST_NUMBER, self::IN_ASCII_DIGIT, self::ST_NUMBER],
                // IN_CHAR              not allowed
                [self::ST_NUMBER, self::IN_CHAR, self::ST_ERROR, $wrongNumberErrorAction],
            ]
        );
        $this->addRules(
            [
                [self::ST_MANTISSA, self::IN_WHITE_SPACE, self::ST_WHITE_SPACE],
                [self::ST_MANTISSA, self::IN_SYNT_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_MANTISSA, self::IN_MUTABLE_CHAR, self::ST_SYNT_LEXEME],
                [self::ST_MANTISSA, self::IN_LEXEME_MODIFIER, self::ST_LEXEME_MODIFIER],
                // IN_ESCAPE_CHAR       not allowed
                [self::ST_MANTISSA, self::IN_ESCAPE_CHAR, self::ST_ERROR, $wrongNumberErrorAction],
                // IN_QUOTE             not allowed
                [self::ST_MANTISSA, self::IN_QUOTE, self::ST_ERROR, $wrongNumberErrorAction],
                // IN_DECIMAL_POINT     not allowed
                [self::ST_MANTISSA, self::IN_DECIMAL_POINT, self::ST_ERROR, $wrongNumberErrorAction],
                [self::ST_MANTISSA, self::IN_ASCII_DIGIT, self::ST_MANTISSA],
                // IN_CHAR              not allowed
                [self::ST_MANTISSA, self::IN_CHAR, self::ST_ERROR, $wrongNumberErrorAction],
            ]
        );

        /** Actions */
        $syntaxLexemeAction = new Zend_Search_Lucene_FSMAction($this, 'addQuerySyntaxLexeme');
        $lexemeModifierAction = new Zend_Search_Lucene_FSMAction($this, 'addLexemeModifier');
        $addLexemeAction = new Zend_Search_Lucene_FSMAction($this, 'addLexeme');
        $addQuotedLexemeAction = new Zend_Search_Lucene_FSMAction($this, 'addQuotedLexeme');
        $addNumberLexemeAction = new Zend_Search_Lucene_FSMAction($this, 'addNumberLexeme');
        $addLexemeCharAction = new Zend_Search_Lucene_FSMAction($this, 'addLexemeChar');

        /** Syntax lexeme */
        $this->addEntryAction(self::ST_SYNT_LEXEME, $syntaxLexemeAction);
        // Two lexemes in succession
        $this->addTransitionAction(self::ST_SYNT_LEXEME, self::ST_SYNT_LEXEME, $syntaxLexemeAction);

        /** Lexeme */
        $this->addEntryAction(self::ST_LEXEME, $addLexemeCharAction);
        $this->addTransitionAction(self::ST_LEXEME, self::ST_LEXEME, $addLexemeCharAction);
        // ST_ESCAPED_CHAR => ST_LEXEME transition is covered by ST_LEXEME entry action

        $this->addTransitionAction(self::ST_LEXEME, self::ST_WHITE_SPACE, $addLexemeAction);
        $this->addTransitionAction(self::ST_LEXEME, self::ST_SYNT_LEXEME, $addLexemeAction);
        $this->addTransitionAction(self::ST_LEXEME, self::ST_QUOTED_LEXEME, $addLexemeAction);
        $this->addTransitionAction(self::ST_LEXEME, self::ST_LEXEME_MODIFIER, $addLexemeAction);
        $this->addTransitionAction(self::ST_LEXEME, self::ST_NUMBER, $addLexemeAction);
        $this->addTransitionAction(self::ST_LEXEME, self::ST_MANTISSA, $addLexemeAction);

        /** Quoted lexeme */
        // We don't need entry action (skeep quote)
        $this->addTransitionAction(self::ST_QUOTED_LEXEME, self::ST_QUOTED_LEXEME, $addLexemeCharAction);
        $this->addTransitionAction(self::ST_ESCAPED_QCHAR, self::ST_QUOTED_LEXEME, $addLexemeCharAction);
        // Closing quote changes state to the ST_WHITE_SPACE   other states are not used
        $this->addTransitionAction(self::ST_QUOTED_LEXEME, self::ST_WHITE_SPACE, $addQuotedLexemeAction);

        /** Lexeme modifier */
        $this->addEntryAction(self::ST_LEXEME_MODIFIER, $lexemeModifierAction);

        /** Number */
        $this->addEntryAction(self::ST_NUMBER, $addLexemeCharAction);
        $this->addEntryAction(self::ST_MANTISSA, $addLexemeCharAction);
        $this->addTransitionAction(self::ST_NUMBER, self::ST_NUMBER, $addLexemeCharAction);
        // ST_NUMBER => ST_MANTISSA transition is covered by ST_MANTISSA entry action
        $this->addTransitionAction(self::ST_MANTISSA, self::ST_MANTISSA, $addLexemeCharAction);

        $this->addTransitionAction(self::ST_NUMBER, self::ST_WHITE_SPACE, $addNumberLexemeAction);
        $this->addTransitionAction(self::ST_NUMBER, self::ST_SYNT_LEXEME, $addNumberLexemeAction);
        $this->addTransitionAction(self::ST_NUMBER, self::ST_LEXEME_MODIFIER, $addNumberLexemeAction);
        $this->addTransitionAction(self::ST_MANTISSA, self::ST_WHITE_SPACE, $addNumberLexemeAction);
        $this->addTransitionAction(self::ST_MANTISSA, self::ST_SYNT_LEXEME, $addNumberLexemeAction);
        $this->addTransitionAction(self::ST_MANTISSA, self::ST_LEXEME_MODIFIER, $addNumberLexemeAction);
    }

    /**
     * Translate input char to an input symbol of state machine
     *
     * @param  string $char
     * @return integer
     */
    private function _translateInput($char)
    {
        if (strpos(self::QUERY_WHITE_SPACE_CHARS, $char) !== false) {
            return self::IN_WHITE_SPACE;
        } elseif (strpos(self::QUERY_SYNT_CHARS, $char) !== false) {
            return self::IN_SYNT_CHAR;
        } elseif (strpos(self::QUERY_MUTABLE_CHARS, $char) !== false) {
            return self::IN_MUTABLE_CHAR;
        } elseif (strpos(self::QUERY_LEXEMEMODIFIER_CHARS, $char) !== false) {
            return self::IN_LEXEME_MODIFIER;
        } elseif (strpos(self::QUERY_ASCIIDIGITS_CHARS, $char) !== false) {
            return self::IN_ASCII_DIGIT;
        } elseif ($char === '"') {
            return self::IN_QUOTE;
        } elseif ($char === '.') {
            return self::IN_DECIMAL_POINT;
        } elseif ($char === '\\') {
            return self::IN_ESCAPE_CHAR;
        } else {
            return self::IN_CHAR;
        }
    }

    /**
     * This method is used to tokenize query string into lexemes
     *
     * @param  string $inputString
     * @param  string $encoding
     * @return array
     * @throws Zend_Search_Lucene_Search_QueryParserException
     */
    public function tokenize($inputString, $encoding)
    {
        $this->reset();

        $this->_lexemes = [];
        $this->_queryString = [];

        if (PHP_OS == 'AIX' && $encoding == '') {
            $encoding = 'ISO8859-1';
        }
        $strLength = iconv_strlen($inputString, $encoding);

        // Workaround for iconv_substr bug
        $inputString .= ' ';

        for ($count = 0; $count < $strLength; $count++) {
            $this->_queryString[$count] = iconv_substr($inputString, $count, 1, $encoding);
        }

        for ($this->_queryStringPosition = 0;
             $this->_queryStringPosition < count($this->_queryString);
             $this->_queryStringPosition++) {
            $this->process($this->_translateInput($this->_queryString[$this->_queryStringPosition]));
        }

        $this->process(self::IN_WHITE_SPACE);

        if ($this->getState() != self::ST_WHITE_SPACE) {
            require_once 'Zend/Search/Lucene/Search/QueryParserException.php';
            throw new Zend_Search_Lucene_Search_QueryParserException('Unexpected end of query');
        }

        $this->_queryString = null;

        return $this->_lexemes;
    }

    /*********************************************************************
     * Actions implementation
     *
     * Actions affect on recognized lexemes list
     *********************************************************************/

    /**
     * Add query syntax lexeme
     *
     * @throws Zend_Search_Lucene_Search_QueryParserException
     */
    public function addQuerySyntaxLexeme()
    {
        $lexeme = $this->_queryString[$this->_queryStringPosition];

        // Process two char lexemes
        if (strpos(self::QUERY_DOUBLECHARLEXEME_CHARS, $lexeme) !== false) {
            // increase current position in a query string
            $this->_queryStringPosition++;

            // check,
            if ($this->_queryStringPosition == count($this->_queryString) ||
                $this->_queryString[$this->_queryStringPosition] != $lexeme
            ) {
                require_once 'Zend/Search/Lucene/Search/QueryParserException.php';
                throw new Zend_Search_Lucene_Search_QueryParserException('Two chars lexeme expected. ' . $this->_positionMsg(
                    ));
            }

            // duplicate character
            $lexeme .= $lexeme;
        }

        $token = new Zend_Search_Lucene_Search_QueryToken(
            Zend_Search_Lucene_Search_QueryToken::TC_SYNTAX_ELEMENT,
            $lexeme,
            $this->_queryStringPosition);

        // Skip this lexeme if it's a field indicator ':' and treat previous as 'field' instead of 'word'
        if ($token->type == Zend_Search_Lucene_Search_QueryToken::TT_FIELD_INDICATOR) {
            $token = array_pop($this->_lexemes);
            if ($token === null || $token->type != Zend_Search_Lucene_Search_QueryToken::TT_WORD) {
                require_once 'Zend/Search/Lucene/Search/QueryParserException.php';
                throw new Zend_Search_Lucene_Search_QueryParserException('Field mark \':\' must follow field name. ' . $this->_positionMsg(
                    ));
            }

            $token->type = Zend_Search_Lucene_Search_QueryToken::TT_FIELD;
        }

        $this->_lexemes[] = $token;
    }

    /**
     * Add lexeme modifier
     */
    public function addLexemeModifier()
    {
        $this->_lexemes[] = new Zend_Search_Lucene_Search_QueryToken(
            Zend_Search_Lucene_Search_QueryToken::TC_SYNTAX_ELEMENT,
            $this->_queryString[$this->_queryStringPosition],
            $this->_queryStringPosition);
    }

    /**
     * Add lexeme
     */
    public function addLexeme()
    {
        $this->_lexemes[] = new Zend_Search_Lucene_Search_QueryToken(
            Zend_Search_Lucene_Search_QueryToken::TC_WORD,
            $this->_currentLexeme,
            $this->_queryStringPosition - 1);

        $this->_currentLexeme = '';
    }

    /**
     * Add quoted lexeme
     */
    public function addQuotedLexeme()
    {
        $this->_lexemes[] = new Zend_Search_Lucene_Search_QueryToken(
            Zend_Search_Lucene_Search_QueryToken::TC_PHRASE,
            $this->_currentLexeme,
            $this->_queryStringPosition);

        $this->_currentLexeme = '';
    }

    /**
     * Add number lexeme
     */
    public function addNumberLexeme()
    {
        $this->_lexemes[] = new Zend_Search_Lucene_Search_QueryToken(
            Zend_Search_Lucene_Search_QueryToken::TC_NUMBER,
            $this->_currentLexeme,
            $this->_queryStringPosition - 1);
        $this->_currentLexeme = '';
    }

    /**
     * Extend lexeme by one char
     */
    public function addLexemeChar()
    {
        $this->_currentLexeme .= $this->_queryString[$this->_queryStringPosition];
    }

    /**
     * Position message
     *
     * @return string
     */
    private function _positionMsg()
    {
        return 'Position is ' . $this->_queryStringPosition . '.';
    }

    /*********************************************************************
     * Syntax errors actions
     *********************************************************************/
    public function lexModifierErrException()
    {
        require_once 'Zend/Search/Lucene/Search/QueryParserException.php';
        throw new Zend_Search_Lucene_Search_QueryParserException('Lexeme modifier character can be followed only by number, white space or query syntax element. ' . $this->_positionMsg(
            ));
    }

    public function quoteWithinLexemeErrException()
    {
        require_once 'Zend/Search/Lucene/Search/QueryParserException.php';
        throw new Zend_Search_Lucene_Search_QueryParserException('Quote within lexeme must be escaped by \'\\\' char. ' . $this->_positionMsg(
            ));
    }

    public function wrongNumberErrException()
    {
        require_once 'Zend/Search/Lucene/Search/QueryParserException.php';
        throw new Zend_Search_Lucene_Search_QueryParserException('Wrong number syntax.' . $this->_positionMsg());
    }
}