/*

 * Copyright 2005 Maksim Orlovich <maksim@kde.org>

 * Copyright (C) 2006 Apple Computer, Inc.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES

 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.

 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#ifndef XPathParser_h

#define XPathParser_h

#if ENABLE(XPATH)

#include "XPathStep.h"

#include "XPathPredicate.h"

namespace WebCore {

    typedef int ExceptionCode;

    class XPathNSResolver;

    namespace XPath {

        class Expression;

        class ParseNode;

        class Predicate;

        struct Token {

            int type;

            String str;

            Step::Axis axis;

            NumericOp::Opcode numop;

            EqTestOp::Opcode eqop;

            Token(int t) : type(t) {}

            Token(int t, const String& v): type(t), str(v) {}

            Token(int t, Step::Axis v): type(t), axis(v) {}

            Token(int t, NumericOp::Opcode v): type(t), numop(v) {}

            Token(int t, EqTestOp::Opcode v): type(t), eqop(v) {}

        };

        class Parser : Noncopyable {

        public:

            Parser();

            XPathNSResolver* resolver() const { return m_resolver.get(); }

            bool expandQName(const String& qName, String& localName, String& namespaceURI);

            Expression* parseStatement(const String& statement, PassRefPtr<XPathNSResolver>, ExceptionCode&);

            static Parser* current() { return currentParser; }

            int lex(void* yylval);

            Expression* m_topExpr;

            bool m_gotNamespaceError;

            void registerParseNode(ParseNode*);

            void unregisterParseNode(ParseNode*);

            void registerPredicateVector(Vector<Predicate*>*);

            void deletePredicateVector(Vector<Predicate*>*);

            void registerExpressionVector(Vector<Expression*>*);

            void deleteExpressionVector(Vector<Expression*>*);

            void registerString(String*);

            void deleteString(String*);

            void registerNodeTest(Step::NodeTest*);

            void deleteNodeTest(Step::NodeTest*);

        private:

            bool isOperatorContext() const;

            void skipWS();

            Token makeTokenAndAdvance(int type, int advance = 1);

            Token makeTokenAndAdvance(int type, NumericOp::Opcode, int advance = 1);

            Token makeTokenAndAdvance(int type, EqTestOp::Opcode, int advance = 1);

            char peekAheadHelper();

            char peekCurHelper();

            Token lexString();

            Token lexNumber();

            bool lexNCName(String&);

            bool lexQName(String&);

            Token nextToken();

            Token nextTokenInternal();

            void reset(const String& data);

            static Parser* currentParser;

            unsigned m_nextPos;

            String m_data;

            int m_lastTokenType;

            RefPtr<XPathNSResolver> m_resolver;

            HashSet<ParseNode*> m_parseNodes;

            HashSet<Vector<Predicate*>*> m_predicateVectors;

            HashSet<Vector<Expression*>*> m_expressionVectors;

            HashSet<String*> m_strings;

            HashSet<Step::NodeTest*> m_nodeTests;

        };

    }

}

#endif // ENABLE(XPATH)

#endif