1/*
2 * Copyright (C) 2009 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#ifndef V8EventListenerList_h
32#define V8EventListenerList_h
33
34#include "bindings/v8/V8EventListener.h"
35#include "bindings/v8/V8HiddenPropertyName.h"
36
37#include <v8.h>
38#include "wtf/PassRefPtr.h"
39
40namespace WebCore {
41
42class Frame;
43
44enum ListenerLookupType {
45    ListenerFindOnly,
46    ListenerFindOrCreate,
47};
48
49// This is a container for V8EventListener objects that uses hidden properties of v8::Object to speed up lookups.
50class V8EventListenerList {
51public:
52    static PassRefPtr<V8EventListener> findWrapper(v8::Local<v8::Value> value, bool isAttribute)
53    {
54        ASSERT(v8::Context::InContext());
55        if (!value->IsObject())
56            return 0;
57
58        v8::Handle<v8::String> wrapperProperty = getHiddenProperty(isAttribute);
59        return doFindWrapper(v8::Local<v8::Object>::Cast(value), wrapperProperty);
60    }
61
62    template<typename WrapperType>
63    static PassRefPtr<V8EventListener> findOrCreateWrapper(v8::Local<v8::Value>, bool isAttribute);
64
65    static void clearWrapper(v8::Handle<v8::Object> listenerObject, bool isAttribute)
66    {
67        v8::Handle<v8::String> wrapperProperty = getHiddenProperty(isAttribute);
68        listenerObject->DeleteHiddenValue(wrapperProperty);
69    }
70
71    static PassRefPtr<EventListener> getEventListener(v8::Local<v8::Value>, bool isAttribute, ListenerLookupType);
72
73private:
74    static V8EventListener* doFindWrapper(v8::Local<v8::Object> object, v8::Handle<v8::String> wrapperProperty)
75    {
76        ASSERT(v8::Context::InContext());
77        v8::HandleScope scope;
78        v8::Local<v8::Value> listener = object->GetHiddenValue(wrapperProperty);
79        if (listener.IsEmpty())
80            return 0;
81        return static_cast<V8EventListener*>(v8::External::Cast(*listener)->Value());
82    }
83
84    static inline v8::Handle<v8::String> getHiddenProperty(bool isAttribute)
85    {
86        return isAttribute ? V8HiddenPropertyName::attributeListener() : V8HiddenPropertyName::listener();
87    }
88};
89
90template<typename WrapperType>
91PassRefPtr<V8EventListener> V8EventListenerList::findOrCreateWrapper(v8::Local<v8::Value> value, bool isAttribute)
92{
93    ASSERT(v8::Context::InContext());
94    if (!value->IsObject())
95        return 0;
96
97    v8::Local<v8::Object> object = v8::Local<v8::Object>::Cast(value);
98    v8::Handle<v8::String> wrapperProperty = getHiddenProperty(isAttribute);
99
100    V8EventListener* wrapper = doFindWrapper(object, wrapperProperty);
101    if (wrapper)
102        return wrapper;
103
104    RefPtr<V8EventListener> wrapperPtr = WrapperType::create(object, isAttribute);
105    if (wrapperPtr)
106        object->SetHiddenValue(wrapperProperty, v8::External::New(wrapperPtr.get()));
107
108    return wrapperPtr;
109}
110
111} // namespace WebCore
112
113#endif // V8EventListenerList_h
114