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#include "config.h"
28#include "core/xml/XPathValue.h"
29
30#include "core/xml/XPathExpressionNode.h"
31#include "core/xml/XPathUtil.h"
32#include "wtf/MathExtras.h"
33#include "wtf/StdLibExtras.h"
34#include <limits>
35
36namespace blink {
37namespace XPath {
38
39const Value::AdoptTag Value::adopt = { };
40
41void ValueData::trace(Visitor* visitor)
42{
43    visitor->trace(m_nodeSet);
44}
45
46void Value::trace(Visitor* visitor)
47{
48    visitor->trace(m_data);
49}
50
51const NodeSet& Value::toNodeSet(EvaluationContext* context) const
52{
53    if (!isNodeSet() && context)
54        context->hadTypeConversionError = true;
55
56    if (!m_data) {
57        DEFINE_STATIC_LOCAL(OwnPtrWillBePersistent<NodeSet>, emptyNodeSet, (NodeSet::create()));
58        return *emptyNodeSet;
59    }
60
61    return m_data->nodeSet();
62}
63
64NodeSet& Value::modifiableNodeSet(EvaluationContext& context)
65{
66    if (!isNodeSet())
67        context.hadTypeConversionError = true;
68
69    if (!m_data)
70        m_data = ValueData::create();
71
72    m_type = NodeSetValue;
73    return m_data->nodeSet();
74}
75
76bool Value::toBoolean() const
77{
78    switch (m_type) {
79    case NodeSetValue:
80        return !m_data->nodeSet().isEmpty();
81    case BooleanValue:
82        return m_bool;
83    case NumberValue:
84        return m_number && !std::isnan(m_number);
85    case StringValue:
86        return !m_data->m_string.isEmpty();
87    }
88    ASSERT_NOT_REACHED();
89    return false;
90}
91
92double Value::toNumber() const
93{
94    switch (m_type) {
95    case NodeSetValue:
96        return Value(toString()).toNumber();
97    case NumberValue:
98        return m_number;
99    case StringValue: {
100        const String& str = m_data->m_string.simplifyWhiteSpace();
101
102        // String::toDouble() supports exponential notation, which is not
103        // allowed in XPath.
104        unsigned len = str.length();
105        for (unsigned i = 0; i < len; ++i) {
106            UChar c = str[i];
107            if (!isASCIIDigit(c) && c != '.'  && c != '-')
108                return std::numeric_limits<double>::quiet_NaN();
109        }
110
111        bool canConvert;
112        double value = str.toDouble(&canConvert);
113        if (canConvert)
114            return value;
115        return std::numeric_limits<double>::quiet_NaN();
116    }
117    case BooleanValue:
118        return m_bool;
119    }
120    ASSERT_NOT_REACHED();
121    return 0.0;
122}
123
124String Value::toString() const
125{
126    switch (m_type) {
127    case NodeSetValue:
128        if (m_data->nodeSet().isEmpty())
129            return "";
130        return stringValue(m_data->nodeSet().firstNode());
131    case StringValue:
132        return m_data->m_string;
133    case NumberValue:
134        if (std::isnan(m_number))
135            return "NaN";
136        if (m_number == 0)
137            return "0";
138        if (std::isinf(m_number))
139            return std::signbit(m_number) ? "-Infinity" : "Infinity";
140        return String::number(m_number);
141    case BooleanValue:
142        return m_bool ? "true" : "false";
143    }
144    ASSERT_NOT_REACHED();
145    return String();
146}
147
148}
149}
150