1/*
2    Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
3    Copyright (C) 2001 Dirk Mueller <mueller@kde.org>
4    Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
5    Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
6
7    This library is free software; you can redistribute it and/or
8    modify it under the terms of the GNU Library General Public
9    License as published by the Free Software Foundation; either
10    version 2 of the License, or (at your option) any later version.
11
12    This library is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15    Library General Public License for more details.
16
17    You should have received a copy of the GNU Library General Public License
18    along with this library; see the file COPYING.LIB.  If not, write to
19    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20    Boston, MA 02110-1301, USA.
21*/
22
23#ifndef ImageResource_h
24#define ImageResource_h
25
26#include "core/fetch/ResourcePtr.h"
27#include "core/svg/graphics/SVGImageCache.h"
28#include "platform/geometry/IntRect.h"
29#include "platform/geometry/IntSizeHash.h"
30#include "platform/geometry/LayoutSize.h"
31#include "platform/graphics/ImageObserver.h"
32#include "wtf/HashMap.h"
33
34namespace blink {
35
36class ImageResourceClient;
37class ResourceFetcher;
38class FloatSize;
39class Length;
40class MemoryCache;
41class RenderObject;
42class SecurityOrigin;
43
44class ImageResource FINAL : public Resource, public ImageObserver {
45    friend class MemoryCache;
46
47public:
48    typedef ImageResourceClient ClientType;
49
50    ImageResource(const ResourceRequest&);
51    ImageResource(blink::Image*);
52    // Exposed for testing
53    ImageResource(const ResourceRequest&, blink::Image*);
54    virtual ~ImageResource();
55
56    virtual void load(ResourceFetcher*, const ResourceLoaderOptions&) OVERRIDE;
57
58    blink::Image* image(); // Returns the nullImage() if the image is not available yet.
59    blink::Image* imageForRenderer(const RenderObject*); // Returns the nullImage() if the image is not available yet.
60    bool hasImage() const { return m_image.get(); }
61    bool currentFrameKnownToBeOpaque(const RenderObject*); // Side effect: ensures decoded image is in cache, therefore should only be called when about to draw the image.
62
63    static std::pair<blink::Image*, float> brokenImage(float deviceScaleFactor); // Returns an image and the image's resolution scale factor.
64    bool willPaintBrokenImage() const;
65
66    bool canRender(const RenderObject& renderer, float multiplier) { return !errorOccurred() && !imageSizeForRenderer(&renderer, multiplier).isEmpty(); }
67
68    void setContainerSizeForRenderer(const ImageResourceClient*, const IntSize&, float);
69    bool usesImageContainerSize() const;
70    bool imageHasRelativeWidth() const;
71    bool imageHasRelativeHeight() const;
72    // The device pixel ratio we got from the server for this image, or 1.0.
73    float devicePixelRatioHeaderValue() const { return m_devicePixelRatioHeaderValue; }
74    bool hasDevicePixelRatioHeaderValue() const { return m_hasDevicePixelRatioHeaderValue; }
75
76    enum SizeType {
77        NormalSize, // Report the size of the image associated with a certain renderer
78        IntrinsicSize // Report the intrinsic size, i.e. ignore whatever has been set extrinsically.
79    };
80    // This method takes a zoom multiplier that can be used to increase the natural size of the image by the zoom.
81    LayoutSize imageSizeForRenderer(const RenderObject*, float multiplier, SizeType = NormalSize); // returns the size of the complete image.
82    void computeIntrinsicDimensions(Length& intrinsicWidth, Length& intrinsicHeight, FloatSize& intrinsicRatio);
83
84    static void updateBitmapImages(HashSet<ImageResource*>&, bool redecodeImages = false);
85
86    bool isAccessAllowed(SecurityOrigin*);
87
88    virtual void didAddClient(ResourceClient*) OVERRIDE;
89    virtual void didRemoveClient(ResourceClient*) OVERRIDE;
90
91    virtual void allClientsRemoved() OVERRIDE;
92
93    virtual void appendData(const char*, int) OVERRIDE;
94    virtual void error(Resource::Status) OVERRIDE;
95    virtual void responseReceived(const ResourceResponse&) OVERRIDE;
96    virtual void finishOnePart() OVERRIDE;
97
98    // For compatibility, images keep loading even if there are HTTP errors.
99    virtual bool shouldIgnoreHTTPStatusCodeErrors() const OVERRIDE { return true; }
100
101    virtual bool isImage() const OVERRIDE { return true; }
102    virtual bool stillNeedsLoad() const OVERRIDE { return !errorOccurred() && status() == Unknown && !isLoading(); }
103
104    // ImageObserver
105    virtual void decodedSizeChanged(const blink::Image*, int delta) OVERRIDE;
106    virtual void didDraw(const blink::Image*) OVERRIDE;
107
108    virtual bool shouldPauseAnimation(const blink::Image*) OVERRIDE;
109    virtual void animationAdvanced(const blink::Image*) OVERRIDE;
110    virtual void changedInRect(const blink::Image*, const IntRect&) OVERRIDE;
111
112protected:
113    virtual bool isSafeToUnlock() const OVERRIDE;
114    virtual void destroyDecodedDataIfPossible() OVERRIDE;
115
116private:
117    void clear();
118
119    void setCustomAcceptHeader();
120    void createImage();
121    void updateImage(bool allDataReceived);
122    void clearImage();
123    // If not null, changeRect is the changed part of the image.
124    void notifyObservers(const IntRect* changeRect = 0);
125
126    virtual void switchClientsToRevalidatedResource() OVERRIDE;
127
128    typedef pair<IntSize, float> SizeAndZoom;
129    typedef HashMap<const ImageResourceClient*, SizeAndZoom> ContainerSizeRequests;
130    ContainerSizeRequests m_pendingContainerSizeRequests;
131    float m_devicePixelRatioHeaderValue;
132
133    RefPtr<blink::Image> m_image;
134    OwnPtr<SVGImageCache> m_svgImageCache;
135    bool m_loadingMultipartContent;
136    bool m_hasDevicePixelRatioHeaderValue;
137};
138
139DEFINE_RESOURCE_TYPE_CASTS(Image);
140
141}
142
143#endif
144