1/*
2 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
3 *           (C) 1999 Antti Koivisto (koivisto@kde.org)
4 * Copyright (C) 2004, 2009 Apple Inc. All rights reserved.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public License
17 * along with this library; see the file COPYING.LIB.  If not, write to
18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 *
21 */
22
23#ifndef ImageLoader_h
24#define ImageLoader_h
25
26#include "CachedImageClient.h"
27#include "CachedResourceHandle.h"
28#include "Timer.h"
29#include <wtf/text/AtomicString.h>
30
31namespace WebCore {
32
33class Element;
34class ImageLoader;
35class RenderImageResource;
36
37template<typename T> class EventSender;
38typedef EventSender<ImageLoader> ImageEventSender;
39
40class ImageLoader : public CachedImageClient {
41public:
42    explicit ImageLoader(Element*);
43    virtual ~ImageLoader();
44
45    // This function should be called when the element is attached to a document; starts
46    // loading if a load hasn't already been started.
47    void updateFromElement();
48
49    // This function should be called whenever the 'src' attribute is set, even if its value
50    // doesn't change; starts new load unconditionally (matches Firefox and Opera behavior).
51    void updateFromElementIgnoringPreviousError();
52
53    void elementDidMoveToNewDocument();
54
55    Element* element() const { return m_element; }
56    bool imageComplete() const { return m_imageComplete; }
57
58    CachedImage* image() const { return m_image.get(); }
59    void setImage(CachedImage*); // Cancels pending beforeload and load events, and doesn't dispatch new ones.
60
61    void setLoadManually(bool loadManually) { m_loadManually = loadManually; }
62
63    bool hasPendingBeforeLoadEvent() const { return m_hasPendingBeforeLoadEvent; }
64    bool hasPendingActivity() const { return m_hasPendingLoadEvent || m_hasPendingErrorEvent; }
65
66    void dispatchPendingEvent(ImageEventSender*);
67
68    static void dispatchPendingBeforeLoadEvents();
69    static void dispatchPendingLoadEvents();
70    static void dispatchPendingErrorEvents();
71
72protected:
73    virtual void notifyFinished(CachedResource*);
74
75private:
76    virtual void dispatchLoadEvent() = 0;
77    virtual String sourceURI(const AtomicString&) const = 0;
78
79    void updatedHasPendingEvent();
80
81    void dispatchPendingBeforeLoadEvent();
82    void dispatchPendingLoadEvent();
83    void dispatchPendingErrorEvent();
84
85    RenderImageResource* renderImageResource();
86    void updateRenderer();
87
88    void setImageWithoutConsideringPendingLoadEvent(CachedImage*);
89    void clearFailedLoadURL();
90
91    void timerFired(Timer<ImageLoader>*);
92
93    Element* m_element;
94    CachedResourceHandle<CachedImage> m_image;
95    Timer<ImageLoader> m_derefElementTimer;
96    AtomicString m_failedLoadURL;
97    bool m_hasPendingBeforeLoadEvent : 1;
98    bool m_hasPendingLoadEvent : 1;
99    bool m_hasPendingErrorEvent : 1;
100    bool m_imageComplete : 1;
101    bool m_loadManually : 1;
102    bool m_elementIsProtected : 1;
103};
104
105}
106
107#endif
108