/*

 * 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 XPathValue_h

#define XPathValue_h

#if ENABLE(XPATH)

#include "PlatformString.h"

#include "XPathNodeSet.h"

namespace WebCore {

    namespace XPath {

        class ValueData : public RefCounted<ValueData> {

        public:            

            static PassRefPtr<ValueData> create() { return adoptRef(new ValueData); }

            static PassRefPtr<ValueData> create(const NodeSet& nodeSet) { return adoptRef(new ValueData(nodeSet)); }

            static PassRefPtr<ValueData> create(const String& string) { return adoptRef(new ValueData(string)); }

            NodeSet m_nodeSet;

            String m_string;

        private:

            ValueData() { }

            ValueData(const NodeSet& nodeSet) : m_nodeSet(nodeSet) { }

            ValueData(const String& string) : m_string(string) { }            

        };

        // Copying Value objects makes their data partially shared, so care has to be taken when dealing with copies.

        class Value {

        public:

            enum Type { NodeSetValue, BooleanValue, NumberValue, StringValue };

            Value(unsigned value) : m_type(NumberValue), m_bool(false), m_number(value) {}

            Value(unsigned long value) : m_type(NumberValue), m_bool(false), m_number(value) {}

            Value(double value) : m_type(NumberValue), m_bool(false), m_number(value) {}

            Value(const char* value) : m_type(StringValue), m_bool(false), m_number(0), m_data(ValueData::create(value)) {}

            Value(const String& value) : m_type(StringValue), m_bool(false), m_number(0), m_data(ValueData::create(value)) {}

            Value(const NodeSet& value) : m_type(NodeSetValue), m_bool(false), m_number(0), m_data(ValueData::create(value)) {}

            Value(Node* value) : m_type(NodeSetValue), m_bool(false), m_number(0), m_data(ValueData::create()) { m_data->m_nodeSet.append(value); }

            // This is needed to safely implement constructing from bool - with normal function overloading, any pointer type would match.

            template<typename T> Value(T);

            static const struct AdoptTag {} adopt;

            Value(NodeSet& value, const AdoptTag&) : m_type(NodeSetValue), m_bool(false), m_number(0),  m_data(ValueData::create()) { value.swap(m_data->m_nodeSet); }

            Type type() const { return m_type; }

            bool isNodeSet() const { return m_type == NodeSetValue; }

            bool isBoolean() const { return m_type == BooleanValue; }

            bool isNumber() const { return m_type == NumberValue; }

            bool isString() const { return m_type == StringValue; }

            const NodeSet& toNodeSet() const;

            NodeSet& modifiableNodeSet();

            bool toBoolean() const;

            double toNumber() const;

            String toString() const;

        private:

            Type m_type;

            bool m_bool;

            double m_number;

            RefPtr<ValueData> m_data;

        };

        template<>

        inline Value::Value(bool value)

            : m_type(BooleanValue)

            , m_bool(value)

            , m_number(0)

        {

        }

    }

}

#endif // ENABLE(XPATH)

#endif // XPath_Value_H