summaryrefslogtreecommitdiff
path: root/dom/html/HTMLImageElement.h
blob: 62323e80164cdf4e3af5ca18d5d130bca33f31a4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_dom_HTMLImageElement_h
#define mozilla_dom_HTMLImageElement_h

#include "mozilla/Attributes.h"
#include "nsGenericHTMLElement.h"
#include "nsImageLoadingContent.h"
#include "nsIDOMHTMLImageElement.h"
#include "imgRequestProxy.h"
#include "Units.h"
#include "nsCycleCollectionParticipant.h"

namespace mozilla {
class EventChainPreVisitor;
namespace dom {

class ImageLoadTask;

class ResponsiveImageSelector;
class HTMLImageElement final : public nsGenericHTMLElement,
                               public nsImageLoadingContent,
                               public nsIDOMHTMLImageElement
{
  friend class HTMLSourceElement;
  friend class HTMLPictureElement;
  friend class ImageLoadTask;
public:
  explicit HTMLImageElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo);

  static already_AddRefed<HTMLImageElement>
    Image(const GlobalObject& aGlobal,
          const Optional<uint32_t>& aWidth,
          const Optional<uint32_t>& aHeight,
          ErrorResult& aError);

  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(HTMLImageElement,
                                           nsGenericHTMLElement)

  // nsISupports
  NS_DECL_ISUPPORTS_INHERITED

  virtual bool Draggable() const override;

  // Element
  virtual bool IsInteractiveHTMLContent(bool aIgnoreTabindex) const override;

  // EventTarget
  virtual void AsyncEventRunning(AsyncEventDispatcher* aEvent) override;

  // nsIDOMHTMLImageElement
  NS_DECL_NSIDOMHTMLIMAGEELEMENT

  NS_IMPL_FROMCONTENT_HTML_WITH_TAG(HTMLImageElement, img)

  // override from nsImageLoadingContent
  CORSMode GetCORSMode() override;

  // nsIContent
  virtual bool ParseAttribute(int32_t aNamespaceID,
                                nsIAtom* aAttribute,
                                const nsAString& aValue,
                                nsAttrValue& aResult) override;
  virtual nsChangeHint GetAttributeChangeHint(const nsIAtom* aAttribute,
                                              int32_t aModType) const override;
  NS_IMETHOD_(bool) IsAttributeMapped(const nsIAtom* aAttribute) const override;
  virtual nsMapRuleToAttributesFunc GetAttributeMappingFunction() const override;

  virtual nsresult PreHandleEvent(EventChainPreVisitor& aVisitor) override;

  bool IsHTMLFocusable(bool aWithMouse, bool *aIsFocusable, int32_t *aTabIndex) override;

  // SetAttr override.  C++ is stupid, so have to override both
  // overloaded methods.
  nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                   const nsAString& aValue, bool aNotify)
  {
    return SetAttr(aNameSpaceID, aName, nullptr, aValue, aNotify);
  }
  virtual nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                           nsIAtom* aPrefix, const nsAString& aValue,
                           bool aNotify) override;

  virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
                              nsIContent* aBindingParent,
                              bool aCompileEventHandlers) override;
  virtual void UnbindFromTree(bool aDeep, bool aNullParent) override;

  virtual EventStates IntrinsicState() const override;
  virtual nsresult Clone(mozilla::dom::NodeInfo *aNodeInfo, nsINode **aResult) const override;

  virtual void NodeInfoChanged() override;

  nsresult CopyInnerTo(Element* aDest);

  void MaybeLoadImage();

  bool IsMap()
  {
    return GetBoolAttr(nsGkAtoms::ismap);
  }
  void SetIsMap(bool aIsMap, ErrorResult& aError)
  {
    SetHTMLBoolAttr(nsGkAtoms::ismap, aIsMap, aError);
  }
  uint32_t Width()
  {
    return GetWidthHeightForImage(mCurrentRequest).width;
  }
  void SetWidth(uint32_t aWidth, ErrorResult& aError)
  {
    SetUnsignedIntAttr(nsGkAtoms::width, aWidth, 0, aError);
  }
  uint32_t Height()
  {
    return GetWidthHeightForImage(mCurrentRequest).height;
  }
  void SetHeight(uint32_t aHeight, ErrorResult& aError)
  {
    SetUnsignedIntAttr(nsGkAtoms::height, aHeight, 0, aError);
  }
  uint32_t NaturalWidth();
  uint32_t NaturalHeight();
  bool Complete();
  uint32_t Hspace()
  {
    return GetUnsignedIntAttr(nsGkAtoms::hspace, 0);
  }
  void SetHspace(uint32_t aHspace, ErrorResult& aError)
  {
    SetUnsignedIntAttr(nsGkAtoms::hspace, aHspace, 0, aError);
  }
  uint32_t Vspace()
  {
    return GetUnsignedIntAttr(nsGkAtoms::vspace, 0);
  }
  void SetVspace(uint32_t aVspace, ErrorResult& aError)
  {
    SetUnsignedIntAttr(nsGkAtoms::vspace, aVspace, 0, aError);
  }

  // The XPCOM versions of the following getters work for Web IDL bindings as well
  void SetAlt(const nsAString& aAlt, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::alt, aAlt, aError);
  }
  void SetSrc(const nsAString& aSrc, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::src, aSrc, aError);
  }
  void SetSrcset(const nsAString& aSrcset, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::srcset, aSrcset, aError);
  }
  void GetCrossOrigin(nsAString& aResult)
  {
    // Null for both missing and invalid defaults is ok, since we
    // always parse to an enum value, so we don't need an invalid
    // default, and we _want_ the missing default to be null.
    GetEnumAttr(nsGkAtoms::crossorigin, nullptr, aResult);
  }
  void SetCrossOrigin(const nsAString& aCrossOrigin, ErrorResult& aError)
  {
    SetOrRemoveNullableStringAttr(nsGkAtoms::crossorigin, aCrossOrigin, aError);
  }
  void SetUseMap(const nsAString& aUseMap, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::usemap, aUseMap, aError);
  }
  void SetName(const nsAString& aName, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::name, aName, aError);
  }
  void SetAlign(const nsAString& aAlign, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::align, aAlign, aError);
  }
  void SetLongDesc(const nsAString& aLongDesc, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::longdesc, aLongDesc, aError);
  }
  void SetSizes(const nsAString& aSizes, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::sizes, aSizes, aError);
  }
  void SetBorder(const nsAString& aBorder, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::border, aBorder, aError);
  }
  void SetReferrerPolicy(const nsAString& aReferrer, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::referrerpolicy, aReferrer, aError);
  }
  void GetReferrerPolicy(nsAString& aReferrer)
  {
    GetEnumAttr(nsGkAtoms::referrerpolicy, EmptyCString().get(), aReferrer);
  }

  net::ReferrerPolicy
  GetImageReferrerPolicy() override
  {
    return GetReferrerPolicyAsEnum();
  }

  int32_t X();
  int32_t Y();
  // Uses XPCOM GetLowsrc.
  void SetLowsrc(const nsAString& aLowsrc, ErrorResult& aError)
  {
    SetHTMLAttr(nsGkAtoms::lowsrc, aLowsrc, aError);
  }

#ifdef DEBUG
  nsIDOMHTMLFormElement* GetForm() const;
#endif
  void SetForm(nsIDOMHTMLFormElement* aForm);
  void ClearForm(bool aRemoveFromForm);

  virtual void DestroyContent() override;

  void MediaFeatureValuesChanged();

  /**
   * Given a hypothetical <img> or <source> tag with the given parameters,
   * return what URI we would attempt to use, if any.  Used by the preloader to
   * resolve sources prior to DOM creation.
   *
   * @param aDocument The document this image would be for, for referencing
   *        viewport width and DPI/zoom
   * @param aIsSourceTag If these parameters are for a <source> tag (as in a
   *        <picture>) rather than an <img> tag. Note that some attrs are unused
   *        when this is true an vice versa
   * @param aSrcAttr [ignored if aIsSourceTag] The src attr for this image.
   * @param aSrcsetAttr The srcset attr for this image/source
   * @param aSizesAttr The sizes attr for this image/source
   * @param aTypeAttr [ignored if !aIsSourceTag] The type attr for this source.
   *                  Should be a void string to differentiate no type attribute
   *                  from an empty one.
   * @param aMediaAttr [ignored if !aIsSourceTag] The media attr for this
   *                   source.  Should be a void string to differentiate no
   *                   media attribute from an empty one.
   * @param aResult A reference to store the resulting URL spec in if we
   *                selected a source.  This value is not guaranteed to parse to
   *                a valid URL, merely the URL that the tag would attempt to
   *                resolve and load (which may be the empty string).  This
   *                parameter is not modified if return value is false.
   * @return True if we were able to select a final source, false if further
   *         sources would be considered.  It follows that this always returns
   *         true if !aIsSourceTag.
   *
   * Note that the return value may be true with an empty string as the result,
   * which implies that the parameters provided describe a tag that would select
   * no source.  This is distinct from a return of false which implies that
   * further <source> or <img> tags would be considered.
   */
  static bool
    SelectSourceForTagWithAttrs(nsIDocument *aDocument,
                                bool aIsSourceTag,
                                const nsAString& aSrcAttr,
                                const nsAString& aSrcsetAttr,
                                const nsAString& aSizesAttr,
                                const nsAString& aTypeAttr,
                                const nsAString& aMediaAttr,
                                nsAString& aResult);

  /**
   * If this image's src pointers to an SVG document, flush the SVG document's
   * use counters to telemetry.  Only used for testing purposes.
   */
  void FlushUseCounters();

protected:
  virtual ~HTMLImageElement();

  // Queues a task to run LoadSelectedImage pending stable state.
  //
  // Pending Bug 1076583 this is only used by the responsive image
  // algorithm (InResponsiveMode()) -- synchronous actions when just
  // using img.src will bypass this, and update source and kick off
  // image load synchronously.
  void QueueImageLoadTask(bool aAlwaysLoad);

  // True if we have a srcset attribute or a <picture> parent, regardless of if
  // any valid responsive sources were parsed from either.
  bool HaveSrcsetOrInPicture();

  // True if we are using the newer image loading algorithm. This will be the
  // only mode after Bug 1076583
  bool InResponsiveMode();

  // True if the given URL and density equal the last URL and density that was loaded by this element.
  bool SelectedSourceMatchesLast(nsIURI* aSelectedSource, double aSelectedDensity);

  // Resolve and load the current mResponsiveSelector (responsive mode) or src
  // attr image.
  nsresult LoadSelectedImage(bool aForce, bool aNotify, bool aAlwaysLoad);

  // True if this string represents a type we would support on <source type>
  static bool SupportedPictureSourceType(const nsAString& aType);

  // Update/create/destroy mResponsiveSelector
  void PictureSourceSrcsetChanged(nsIContent *aSourceNode,
                                  const nsAString& aNewValue, bool aNotify);
  void PictureSourceSizesChanged(nsIContent *aSourceNode,
                                 const nsAString& aNewValue, bool aNotify);
  // As we re-run the source selection on these mutations regardless,
  // we don't actually care which changed or to what
  void PictureSourceMediaOrTypeChanged(nsIContent *aSourceNode, bool aNotify);

  void PictureSourceAdded(nsIContent *aSourceNode);
  // This should be called prior to the unbind, such that nextsibling works
  void PictureSourceRemoved(nsIContent *aSourceNode);

  // Re-evaluates all source nodes (picture <source>,<img>) and finds
  // the best source set for mResponsiveSelector. If a better source
  // is found, creates a new selector and feeds the source to it. If
  // the current ResponsiveSelector is not changed, runs
  // SelectImage(true) to re-evaluate its candidates.
  //
  // Because keeping the existing selector is the common case (and we
  // often do no-op reselections), this does not re-parse values for
  // the existing mResponsiveSelector, meaning you need to update its
  // parameters as appropriate before calling (or null it out to force
  // recreation)
  //
  // Returns true if the source has changed, and false otherwise.
  bool UpdateResponsiveSource();

  // Given a <source> node that is a previous sibling *or* ourselves, try to
  // create a ResponsiveSelector.

  // If the node's srcset/sizes make for an invalid selector, returns
  // false. This does not guarantee the resulting selector matches an image,
  // only that it is valid.
  bool TryCreateResponsiveSelector(nsIContent *aSourceNode);

  CSSIntPoint GetXY();
  virtual JSObject* WrapNode(JSContext *aCx, JS::Handle<JSObject*> aGivenProto) override;
  void UpdateFormOwner();

  virtual nsresult BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 nsAttrValueOrString* aValue,
                                 bool aNotify) override;

  virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                const nsAttrValue* aValue, bool aNotify) override;

  // This is a weak reference that this element and the HTMLFormElement
  // cooperate in maintaining.
  HTMLFormElement* mForm;

  // Created when we're tracking responsive image state
  RefPtr<ResponsiveImageSelector> mResponsiveSelector;

private:
  bool SourceElementMatches(nsIContent* aSourceNode);

  static void MapAttributesIntoRule(const nsMappedAttributes* aAttributes,
                                    nsRuleData* aData);

  bool mInDocResponsiveContent;
  RefPtr<ImageLoadTask> mPendingImageLoadTask;

  // Last URL that was attempted to load by this element.
  nsCOMPtr<nsIURI> mLastSelectedSource;
  // Last pixel density that was selected.
  double mCurrentDensity;
};

} // namespace dom
} // namespace mozilla

#endif /* mozilla_dom_HTMLImageElement_h */