<?php
// $Id$

/**
 * @file
 * Lexer for TQL
 */
class TqlLexer {
  private $data;
  private $N;
  public $token;
  public $value;
  public $node;
  private $line;
  private $state = 1;

  function __construct($data) {
    $this->data = $data;
    $this->N = 0;
    $this->line = 1;
  }

  function init(&$node) {
    $node->value = $this->value;
    $node->type = $this->token;
    $node->column = $this->N;
    $node->line = $this->line;
    return $node;
  }


  private $_yy_state = 1;
  private $_yy_stack = array();

  function yylex() {
    return $this->{'yylex' . $this->_yy_state}();
  }

  function yypushstate($state) {
    array_push($this->_yy_stack, $this->_yy_state);
    $this->_yy_state = $state;
  }

  function yypopstate() {
    $this->_yy_state = array_pop($this->_yy_stack);
  }

  function yybegin($state) {
    $this->_yy_state = $state;
  }


  function yylex1() {
    $tokenMap = array(
      1 => 0,
      2 => 0,
      3 => 0,
      4 => 0,
      5 => 0,
      6 => 0,
      7 => 0,
      8 => 0,
      9 => 0,
      10 => 0,
    );
    if ($this->N >= drupal_strlen($this->data)) {
      return FALSE; // end of input
    }
    $yy_global_pattern = "/^(\\b[nN][oO][tT]\\b|-)|^(\\b[aA][nN][dD]\\b)|^(\\b[oO][rR]\\b)|^(\\b[xX][oO][rR]\\b)|^(\\()|^(\\))|^(\")|^([^\"\s()]+)|^(\\s)|^(.)/";

    do {
      if (preg_match($yy_global_pattern, drupal_substr($this->data, $this->N), $yymatches)) {
        $yysubmatches = $yymatches;
        $yymatches = array_filter($yymatches, 'strlen'); // remove empty sub-patterns
        if (!count($yymatches)) {
          throw new Exception('Error: lexing failed because a rule matched' .
                        'an empty string.  Input "' . drupal_substr($this->data,
          $this->N, 5) . '... state START');
        }
        next($yymatches); // skip global match
        $this->token = key($yymatches); // token number
        if ($tokenMap[$this->token]) {
          // extract sub-patterns for passing to lex function
          $yysubmatches = array_slice($yysubmatches, $this->token + 1,
          $tokenMap[$this->token]);
        }
        else {
          $yysubmatches = array();
        }
        $this->value = current($yymatches); // token value
        $r = $this->{'yy_r1_' . $this->token}($yysubmatches);
        if ($r === NULL) {
          $this->N += drupal_strlen($this->value);
          $this->line += substr_count("\n", $this->value);
          // accept this token
          return TRUE;
        }
        elseif ($r === TRUE) {
          // we have changed state
          // process this token in the new state
          return $this->yylex();
        }
        elseif ($r === FALSE) {
          $this->N += drupal_strlen($this->value);
          $this->line += substr_count("\n", $this->value);
          if ($this->N >= drupal_strlen($this->data)) {
            return FALSE; // end of input
          }
          // skip this token
          continue;
        }
        else {
          $yy_yymore_patterns = array(
            1 => "^(\\b[aA][nN][dD]\\b)|^(\\b[oO][rR]\\b)|^(\\b[xX][oO][rR]\\b)|^(\\()|^(\\))|^(\")|^([^\"\s()]+)|^(\\s)|^(.)",
            2 => "^(\\b[oO][rR]\\b)|^(\\b[xX][oO][rR]\\b)|^(\\()|^(\\))|^(\")|^([^\"\s()]+)|^(\\s)|^(.)",
            3 => "^(\\b[xX][oO][rR]\\b)|^(\\()|^(\\))|^(\")|^([^\"\s()]+)|^(\\s)|^(.)",
            4 => "^(\\()|^(\\))|^(\")|^([^\"\s()]+)|^(\\s)|^(.)",
            5 => "^(\\))|^(\")|^([^\"\s()]+)|^(\\s)|^(.)",
            6 => "^(\")|^([^\"\s()]+)|^(\\s)|^(.)",
            7 => "^([^\"\s()]+)|^(\\s)|^(.)",
            8 => "^(\\s)|^(.)",
            9 => "^(.)",
            10 => "",
          );

        // yymore is needed
        do {
          if (!drupal_strlen($yy_yymore_patterns[$this->token])) {
            throw new Exception('cannot do yymore for the last token');
          }
          if (preg_match($yy_yymore_patterns[$this->token],
          drupal_substr($this->data, $this->N), $yymatches)) {
            $yymatches = array_filter($yymatches, 'strlen'); // remove empty sub-patterns
            next($yymatches); // skip global match
            $this->token = key($yymatches); // token number
            $this->value = current($yymatches); // token value
            $this->line = substr_count("\n", $this->value);
          }
          $r = $this->{'yy_r1_' . $this->token}();
        } while ($r !== NULL || !$r);
        if ($r === TRUE) {
          // we have changed state
          // process this token in the new state
          return $this->yylex();
        }
        else {
          // accept
          $this->N += drupal_strlen($this->value);
          $this->line += substr_count("\n", $this->value);
          return TRUE;
        }
        }
      }
      else {
        throw new Exception('Unexpected input at line' . $this->line .
                    ': ' . $this->data[$this->N]);
      }
      break;
    } while (TRUE);

  } // end function


  const START = 1;
  function yy_r1_1($yy_subpatterns) {
    $this->token = TqlParser::TK_NOT;
    $this->node = $this->init(new TqlNot());
  }

  function yy_r1_2($yy_subpatterns) {
    $this->token = TqlParser::TK_AND;
    $this->node = $this->init(new TqlAnd());
  }

  function yy_r1_3($yy_subpatterns) {
    $this->token = TqlParser::TK_OR;
    $this->node = $this->init(new TqlOr());
  }

  function yy_r1_4($yy_subpatterns) {
    $this->token = TqlParser::TK_XOR;
    $this->node = $this->init(new TqlXor());
  }

  function yy_r1_5($yy_subpatterns) {
    $this->token = TqlParser::TK_LPAREN;
    $this->node = $this->init(new TqlNode());
  }

  function yy_r1_6($yy_subpatterns) {
    $this->token = TqlParser::TK_RPAREN;
    $this->node = $this->init(new TqlNode());
  }

  function yy_r1_7($yy_subpatterns) {
    $this->token = TqlParser::TK_QUOTE;
    $this->node = $this->init(new TqlNode());
    $this->yybegin(self::IN_QUOTE);
  }

  function yy_r1_8($yy_subpatterns) {
    $this->token = TqlParser::TK_IDENTIFIER;
    $this->node = $this->init(new TqlIdentifier());
  }

  function yy_r1_9($yy_subpatterns) {
    return FALSE;
  }

  function yy_r1_10($yy_subpatterns) {
    return FALSE;
  }


  function yylex2() {
    $tokenMap = array(
      1 => 0,
      2 => 0,
    );
    if ($this->N >= drupal_strlen($this->data)) {
      return FALSE; // end of input
    }
    $yy_global_pattern = "/^(\")|^([^\"]+)/";

    do {
      if (preg_match($yy_global_pattern, drupal_substr($this->data, $this->N), $yymatches)) {
        $yysubmatches = $yymatches;
        $yymatches = array_filter($yymatches, 'strlen'); // remove empty sub-patterns
        if (!count($yymatches)) {
          throw new Exception('Error: lexing failed because a rule matched' .
                        'an empty string.  Input "' . drupal_substr($this->data,
          $this->N, 5) . '... state IN_QUOTE');
        }
        next($yymatches); // skip global match
        $this->token = key($yymatches); // token number
        if ($tokenMap[$this->token]) {
          // extract sub-patterns for passing to lex function
          $yysubmatches = array_slice($yysubmatches, $this->token + 1,
          $tokenMap[$this->token]);
        }
        else {
          $yysubmatches = array();
        }
        $this->value = current($yymatches); // token value
        $r = $this->{'yy_r2_' . $this->token}($yysubmatches);
        if ($r === NULL) {
          $this->N += drupal_strlen($this->value);
          $this->line += substr_count("\n", $this->value);
          // accept this token
          return TRUE;
        }
        elseif ($r === TRUE) {
          // we have changed state
          // process this token in the new state
          return $this->yylex();
        }
        elseif ($r === FALSE) {
          $this->N += drupal_strlen($this->value);
          $this->line += substr_count("\n", $this->value);
          if ($this->N >= drupal_strlen($this->data)) {
            return FALSE; // end of input
          }
          // skip this token
          continue;
        }
        else {
          $yy_yymore_patterns = array(
            1 => "^([^\"]+)",
            2 => "",
          );

        // yymore is needed
        do {
          if (!drupal_strlen($yy_yymore_patterns[$this->token])) {
            throw new Exception('cannot do yymore for the last token');
          }
          if (preg_match($yy_yymore_patterns[$this->token],
          drupal_substr($this->data, $this->N), $yymatches)) {
            $yymatches = array_filter($yymatches, 'strlen'); // remove empty sub-patterns
            next($yymatches); // skip global match
            $this->token = key($yymatches); // token number
            $this->value = current($yymatches); // token value
            $this->line = substr_count("\n", $this->value);
          }
          $r = $this->{'yy_r2_' . $this->token}();
        } while ($r !== NULL || !$r);
        if ($r === TRUE) {
          // we have changed state
          // process this token in the new state
          return $this->yylex();
        }
        else {
          // accept
          $this->N += drupal_strlen($this->value);
          $this->line += substr_count("\n", $this->value);
          return TRUE;
        }
        }
      }
      else {
        throw new Exception('Unexpected input at line' . $this->line .
                    ': ' . $this->data[$this->N]);
      }
      break;
    } while (TRUE);

  } // end function


  const IN_QUOTE = 2;
  function yy_r2_1($yy_subpatterns) {
    $this->token = TqlParser::TK_QUOTE;
    $this->node = $this->init(new TqlNode());
    $this->yybegin(self::START);
  }

  function yy_r2_2($yy_subpatterns) {
    $this->token = TqlParser::TK_IDENTIFIER;
    $this->node = $this->init(new TqlIdentifier());
  }
}