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 XPathPredicate_h
28#define XPathPredicate_h
29
30#if ENABLE(XPATH)
31
32#include "XPathExpressionNode.h"
33#include "XPathValue.h"
34
35namespace WebCore {
36
37    namespace XPath {
38
39        class Number : public Expression {
40        public:
41            Number(double);
42        private:
43            virtual Value evaluate() const;
44            virtual Value::Type resultType() const { return Value::NumberValue; }
45
46            Value m_value;
47        };
48
49        class StringExpression : public Expression {
50        public:
51            StringExpression(const String&);
52        private:
53            virtual Value evaluate() const;
54            virtual Value::Type resultType() const { return Value::StringValue; }
55
56            Value m_value;
57        };
58
59        class Negative : public Expression {
60        private:
61            virtual Value evaluate() const;
62            virtual Value::Type resultType() const { return Value::NumberValue; }
63        };
64
65        class NumericOp : public Expression {
66        public:
67            enum Opcode {
68                OP_Add, OP_Sub, OP_Mul, OP_Div, OP_Mod
69            };
70            NumericOp(Opcode, Expression* lhs, Expression* rhs);
71        private:
72            virtual Value evaluate() const;
73            virtual Value::Type resultType() const { return Value::NumberValue; }
74
75            Opcode m_opcode;
76        };
77
78        class EqTestOp : public Expression {
79        public:
80            enum Opcode { OP_EQ, OP_NE, OP_GT, OP_LT, OP_GE, OP_LE };
81            EqTestOp(Opcode, Expression* lhs, Expression* rhs);
82            virtual Value evaluate() const;
83        private:
84            virtual Value::Type resultType() const { return Value::BooleanValue; }
85            bool compare(const Value&, const Value&) const;
86
87            Opcode m_opcode;
88        };
89
90        class LogicalOp : public Expression {
91        public:
92            enum Opcode { OP_And, OP_Or };
93            LogicalOp(Opcode, Expression* lhs, Expression* rhs);
94        private:
95            virtual Value::Type resultType() const { return Value::BooleanValue; }
96            bool shortCircuitOn() const;
97            virtual Value evaluate() const;
98
99            Opcode m_opcode;
100        };
101
102        class Union : public Expression {
103        private:
104            virtual Value evaluate() const;
105            virtual Value::Type resultType() const { return Value::NodeSetValue; }
106        };
107
108        class Predicate {
109            WTF_MAKE_NONCOPYABLE(Predicate); WTF_MAKE_FAST_ALLOCATED;
110        public:
111            Predicate(Expression*);
112            ~Predicate();
113            bool evaluate() const;
114
115            bool isContextPositionSensitive() const { return m_expr->isContextPositionSensitive() || m_expr->resultType() == Value::NumberValue; }
116            bool isContextSizeSensitive() const { return m_expr->isContextSizeSensitive(); }
117
118        private:
119            Expression* m_expr;
120        };
121
122    }
123
124}
125
126#endif // ENABLE(XPATH)
127
128#endif // XPathPredicate_h
129