/*

 * Copyright 2005 Frerich Raabe <raabe@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 XPathPredicate_h

#define XPathPredicate_h

#if ENABLE(XPATH)

#include "XPathExpressionNode.h"

#include "XPathValue.h"

namespace WebCore {

    namespace XPath {

        class Number : public Expression {

        public:

            Number(double);

        private:

            virtual Value evaluate() const;

            virtual Value::Type resultType() const { return Value::NumberValue; }

            Value m_value;

        };

        class StringExpression : public Expression {

        public:

            StringExpression(const String&);

        private:

            virtual Value evaluate() const;

            virtual Value::Type resultType() const { return Value::StringValue; }

            Value m_value;

        };

        class Negative : public Expression {

        private:

            virtual Value evaluate() const;

            virtual Value::Type resultType() const { return Value::NumberValue; }

        };

        class NumericOp : public Expression {

        public:

            enum Opcode {

                OP_Add, OP_Sub, OP_Mul, OP_Div, OP_Mod

            };

            NumericOp(Opcode, Expression* lhs, Expression* rhs);

        private:

            virtual Value evaluate() const;

            virtual Value::Type resultType() const { return Value::NumberValue; }

            Opcode m_opcode;

        };

        class EqTestOp : public Expression {

        public:

            enum Opcode { OP_EQ, OP_NE, OP_GT, OP_LT, OP_GE, OP_LE };

            EqTestOp(Opcode, Expression* lhs, Expression* rhs);

            virtual Value evaluate() const;

        private:

            virtual Value::Type resultType() const { return Value::BooleanValue; }

            bool compare(const Value&, const Value&) const;

            Opcode m_opcode;

        };

        class LogicalOp : public Expression {

        public:

            enum Opcode { OP_And, OP_Or };

            LogicalOp(Opcode, Expression* lhs, Expression* rhs);

        private:

            virtual Value::Type resultType() const { return Value::BooleanValue; }

            bool shortCircuitOn() const;

            virtual Value evaluate() const;

            Opcode m_opcode;

        };

        class Union : public Expression {

        private:

            virtual Value evaluate() const;

            virtual Value::Type resultType() const { return Value::NodeSetValue; }

        };

        class Predicate : public Noncopyable {

        public:

            Predicate(Expression*);

            ~Predicate();

            bool evaluate() const;

            bool isContextPositionSensitive() const { return m_expr->isContextPositionSensitive() || m_expr->resultType() == Value::NumberValue; }

            bool isContextSizeSensitive() const { return m_expr->isContextSizeSensitive(); }

        private:

            Expression* m_expr;

        };

    }

}

#endif // ENABLE(XPATH)

#endif // XPathPredicate_h