1/*
2 * Copyright 2005 Frerich Raabe <raabe@kde.org>
3 * Copyright (C) 2006 Apple Computer, Inc.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#ifndef XPathValue_h
28#define XPathValue_h
29
30#include "core/xml/XPathNodeSet.h"
31#include "wtf/text/WTFString.h"
32
33namespace blink {
34
35namespace XPath {
36
37struct EvaluationContext;
38
39class ValueData : public RefCountedWillBeGarbageCollectedFinalized<ValueData> {
40public:
41    static PassRefPtrWillBeRawPtr<ValueData> create() { return adoptRefWillBeNoop(new ValueData); }
42    static PassRefPtrWillBeRawPtr<ValueData> create(const NodeSet& nodeSet) { return adoptRefWillBeNoop(new ValueData(nodeSet)); }
43    static PassRefPtrWillBeRawPtr<ValueData> create(PassOwnPtrWillBeRawPtr<NodeSet> nodeSet) { return adoptRefWillBeNoop(new ValueData(nodeSet)); }
44    static PassRefPtrWillBeRawPtr<ValueData> create(const String& string) { return adoptRefWillBeNoop(new ValueData(string)); }
45    void trace(Visitor*);
46    NodeSet& nodeSet() { return *m_nodeSet; }
47
48    String m_string;
49
50private:
51    ValueData() : m_nodeSet(NodeSet::create()) { }
52    explicit ValueData(const NodeSet& nodeSet) : m_nodeSet(NodeSet::create(nodeSet)) { }
53    explicit ValueData(PassOwnPtrWillBeRawPtr<NodeSet> nodeSet) : m_nodeSet(nodeSet) { }
54    explicit ValueData(const String& string) : m_string(string), m_nodeSet(NodeSet::create()) { }
55
56    OwnPtrWillBeMember<NodeSet> m_nodeSet;
57};
58
59// Copying Value objects makes their data partially shared, so care has to be taken when dealing with copies.
60class Value {
61    DISALLOW_ALLOCATION();
62public:
63    enum Type { NodeSetValue, BooleanValue, NumberValue, StringValue };
64
65    Value(unsigned value) : m_type(NumberValue), m_bool(false), m_number(value) { }
66    Value(unsigned long value) : m_type(NumberValue), m_bool(false), m_number(value) { }
67    Value(double value) : m_type(NumberValue), m_bool(false), m_number(value) { }
68
69    Value(const char* value) : m_type(StringValue), m_bool(false), m_number(0), m_data(ValueData::create(value)) { }
70    Value(const String& value) : m_type(StringValue), m_bool(false), m_number(0), m_data(ValueData::create(value)) { }
71    Value(const NodeSet& value) : m_type(NodeSetValue), m_bool(false), m_number(0), m_data(ValueData::create(value)) { }
72    Value(Node* value) : m_type(NodeSetValue), m_bool(false), m_number(0), m_data(ValueData::create()) { m_data->nodeSet().append(value); }
73    void trace(Visitor*);
74
75    // This is needed to safely implement constructing from bool - with normal
76    // function overloading, any pointer type would match.
77    template<typename T> Value(T);
78
79    static const struct AdoptTag { } adopt;
80    Value(PassOwnPtrWillBeRawPtr<NodeSet> value, const AdoptTag&) : m_type(NodeSetValue), m_bool(false), m_number(0),  m_data(ValueData::create(value)) { }
81
82    Type type() const { return m_type; }
83
84    bool isNodeSet() const { return m_type == NodeSetValue; }
85    bool isBoolean() const { return m_type == BooleanValue; }
86    bool isNumber() const { return m_type == NumberValue; }
87    bool isString() const { return m_type == StringValue; }
88
89    // If this is called during XPathExpression::evaluate(), EvaluationContext
90    // should be passed.
91    const NodeSet& toNodeSet(EvaluationContext*) const;
92    NodeSet& modifiableNodeSet(EvaluationContext&);
93    bool toBoolean() const;
94    double toNumber() const;
95    String toString() const;
96
97private:
98    Type m_type;
99    bool m_bool;
100    double m_number;
101    RefPtrWillBeMember<ValueData> m_data;
102};
103
104template<>
105inline Value::Value(bool value)
106    : m_type(BooleanValue)
107    , m_bool(value)
108    , m_number(0)
109{
110}
111
112}
113
114}
115#endif // XPathValue_h
116