1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7 #include "AccessibleCaret.h"
8
9 #include "AccessibleCaretLogger.h"
10 #include "mozilla/FloatingPoint.h"
11 #include "mozilla/PresShell.h"
12 #include "mozilla/StaticPrefs_layout.h"
13 #include "mozilla/ToString.h"
14 #include "nsCanvasFrame.h"
15 #include "nsCaret.h"
16 #include "nsCSSFrameConstructor.h"
17 #include "nsDOMTokenList.h"
18 #include "nsIFrame.h"
19 #include "nsLayoutUtils.h"
20 #include "nsPlaceholderFrame.h"
21
22 namespace mozilla {
23 using namespace dom;
24
25 #undef AC_LOG
26 #define AC_LOG(message, ...) \
27 AC_LOG_BASE("AccessibleCaret (%p): " message, this, ##__VA_ARGS__);
28
29 #undef AC_LOGV
30 #define AC_LOGV(message, ...) \
31 AC_LOGV_BASE("AccessibleCaret (%p): " message, this, ##__VA_ARGS__);
32
33 NS_IMPL_ISUPPORTS(AccessibleCaret::DummyTouchListener, nsIDOMEventListener)
34
35 const nsLiteralString AccessibleCaret::sTextOverlayElementId =
36 u"text-overlay"_ns;
37 const nsLiteralString AccessibleCaret::sCaretImageElementId = u"image"_ns;
38
39 #define AC_PROCESS_ENUM_TO_STREAM(e) \
40 case (e): \
41 aStream << #e; \
42 break;
operator <<(std::ostream & aStream,const AccessibleCaret::Appearance & aAppearance)43 std::ostream& operator<<(std::ostream& aStream,
44 const AccessibleCaret::Appearance& aAppearance) {
45 using Appearance = AccessibleCaret::Appearance;
46 switch (aAppearance) {
47 AC_PROCESS_ENUM_TO_STREAM(Appearance::None);
48 AC_PROCESS_ENUM_TO_STREAM(Appearance::Normal);
49 AC_PROCESS_ENUM_TO_STREAM(Appearance::NormalNotShown);
50 AC_PROCESS_ENUM_TO_STREAM(Appearance::Left);
51 AC_PROCESS_ENUM_TO_STREAM(Appearance::Right);
52 }
53 return aStream;
54 }
55
operator <<(std::ostream & aStream,const AccessibleCaret::PositionChangedResult & aResult)56 std::ostream& operator<<(
57 std::ostream& aStream,
58 const AccessibleCaret::PositionChangedResult& aResult) {
59 using PositionChangedResult = AccessibleCaret::PositionChangedResult;
60 switch (aResult) {
61 AC_PROCESS_ENUM_TO_STREAM(PositionChangedResult::NotChanged);
62 AC_PROCESS_ENUM_TO_STREAM(PositionChangedResult::Position);
63 AC_PROCESS_ENUM_TO_STREAM(PositionChangedResult::Zoom);
64 AC_PROCESS_ENUM_TO_STREAM(PositionChangedResult::Invisible);
65 }
66 return aStream;
67 }
68 #undef AC_PROCESS_ENUM_TO_STREAM
69
70 // -----------------------------------------------------------------------------
71 // Implementation of AccessibleCaret methods
72
AccessibleCaret(PresShell * aPresShell)73 AccessibleCaret::AccessibleCaret(PresShell* aPresShell)
74 : mPresShell(aPresShell) {
75 // Check all resources required.
76 if (mPresShell) {
77 MOZ_ASSERT(RootFrame());
78 MOZ_ASSERT(mPresShell->GetDocument());
79 InjectCaretElement(mPresShell->GetDocument());
80 }
81 }
82
~AccessibleCaret()83 AccessibleCaret::~AccessibleCaret() {
84 if (mPresShell) {
85 RemoveCaretElement(mPresShell->GetDocument());
86 }
87 }
88
SetAppearance(Appearance aAppearance)89 void AccessibleCaret::SetAppearance(Appearance aAppearance) {
90 if (mAppearance == aAppearance) {
91 return;
92 }
93
94 ErrorResult rv;
95 CaretElement().ClassList()->Remove(AppearanceString(mAppearance), rv);
96 MOZ_ASSERT(!rv.Failed(), "Remove old appearance failed!");
97
98 CaretElement().ClassList()->Add(AppearanceString(aAppearance), rv);
99 MOZ_ASSERT(!rv.Failed(), "Add new appearance failed!");
100
101 AC_LOG("%s: %s -> %s", __FUNCTION__, ToString(mAppearance).c_str(),
102 ToString(aAppearance).c_str());
103
104 mAppearance = aAppearance;
105
106 // Need to reset rect since the cached rect will be compared in SetPosition.
107 if (mAppearance == Appearance::None) {
108 ClearCachedData();
109 }
110 }
111
112 /* static */
AppearanceString(Appearance aAppearance)113 nsAutoString AccessibleCaret::AppearanceString(Appearance aAppearance) {
114 nsAutoString string;
115 switch (aAppearance) {
116 case Appearance::None:
117 string = u"none"_ns;
118 break;
119 case Appearance::NormalNotShown:
120 string = u"hidden"_ns;
121 break;
122 case Appearance::Normal:
123 string = u"normal"_ns;
124 break;
125 case Appearance::Right:
126 string = u"right"_ns;
127 break;
128 case Appearance::Left:
129 string = u"left"_ns;
130 break;
131 }
132 return string;
133 }
134
Intersects(const AccessibleCaret & aCaret) const135 bool AccessibleCaret::Intersects(const AccessibleCaret& aCaret) const {
136 MOZ_ASSERT(mPresShell == aCaret.mPresShell);
137
138 if (!IsVisuallyVisible() || !aCaret.IsVisuallyVisible()) {
139 return false;
140 }
141
142 nsRect rect =
143 nsLayoutUtils::GetRectRelativeToFrame(&CaretElement(), RootFrame());
144 nsRect rhsRect = nsLayoutUtils::GetRectRelativeToFrame(&aCaret.CaretElement(),
145 RootFrame());
146 return rect.Intersects(rhsRect);
147 }
148
Contains(const nsPoint & aPoint,TouchArea aTouchArea) const149 bool AccessibleCaret::Contains(const nsPoint& aPoint,
150 TouchArea aTouchArea) const {
151 if (!IsVisuallyVisible()) {
152 return false;
153 }
154
155 nsRect textOverlayRect =
156 nsLayoutUtils::GetRectRelativeToFrame(TextOverlayElement(), RootFrame());
157 nsRect caretImageRect =
158 nsLayoutUtils::GetRectRelativeToFrame(CaretImageElement(), RootFrame());
159
160 if (aTouchArea == TouchArea::CaretImage) {
161 return caretImageRect.Contains(aPoint);
162 }
163
164 MOZ_ASSERT(aTouchArea == TouchArea::Full, "Unexpected TouchArea type!");
165 return textOverlayRect.Contains(aPoint) || caretImageRect.Contains(aPoint);
166 }
167
EnsureApzAware()168 void AccessibleCaret::EnsureApzAware() {
169 // If the caret element was cloned, the listener might have been lost. So
170 // if that's the case we register a dummy listener if there isn't one on
171 // the element already.
172 if (!CaretElement().IsApzAware()) {
173 // FIXME(emilio): Is this needed anymore?
174 CaretElement().AddEventListener(u"touchstart"_ns, mDummyTouchListener,
175 false);
176 }
177 }
178
IsInPositionFixedSubtree() const179 bool AccessibleCaret::IsInPositionFixedSubtree() const {
180 return nsLayoutUtils::IsInPositionFixedSubtree(
181 mImaginaryCaretReferenceFrame.GetFrame());
182 }
183
InjectCaretElement(Document * aDocument)184 void AccessibleCaret::InjectCaretElement(Document* aDocument) {
185 ErrorResult rv;
186 RefPtr<Element> element = CreateCaretElement(aDocument);
187 mCaretElementHolder = aDocument->InsertAnonymousContent(*element, rv);
188
189 MOZ_ASSERT(!rv.Failed(), "Insert anonymous content should not fail!");
190 MOZ_ASSERT(mCaretElementHolder, "We must have anonymous content!");
191
192 // InsertAnonymousContent will clone the element to make an AnonymousContent.
193 // Since event listeners are not being cloned when cloning a node, we need to
194 // add the listener here.
195 EnsureApzAware();
196 }
197
CreateCaretElement(Document * aDocument) const198 already_AddRefed<Element> AccessibleCaret::CreateCaretElement(
199 Document* aDocument) const {
200 // Content structure of AccessibleCaret
201 // <div class="moz-accessiblecaret"> <- CaretElement()
202 // <div id="text-overlay"> <- TextOverlayElement()
203 // <div id="image"> <- CaretImageElement()
204
205 ErrorResult rv;
206 RefPtr<Element> parent = aDocument->CreateHTMLElement(nsGkAtoms::div);
207 parent->ClassList()->Add(u"moz-accessiblecaret"_ns, rv);
208 parent->ClassList()->Add(u"none"_ns, rv);
209
210 auto CreateAndAppendChildElement =
211 [aDocument, &parent](const nsLiteralString& aElementId) {
212 RefPtr<Element> child = aDocument->CreateHTMLElement(nsGkAtoms::div);
213 child->SetAttr(kNameSpaceID_None, nsGkAtoms::id, aElementId, true);
214 parent->AppendChildTo(child, false, IgnoreErrors());
215 };
216
217 CreateAndAppendChildElement(sTextOverlayElementId);
218 CreateAndAppendChildElement(sCaretImageElementId);
219
220 return parent.forget();
221 }
222
RemoveCaretElement(Document * aDocument)223 void AccessibleCaret::RemoveCaretElement(Document* aDocument) {
224 CaretElement().RemoveEventListener(u"touchstart"_ns, mDummyTouchListener,
225 false);
226
227 aDocument->RemoveAnonymousContent(*mCaretElementHolder, IgnoreErrors());
228 }
229
ClearCachedData()230 void AccessibleCaret::ClearCachedData() {
231 mImaginaryCaretRect = nsRect();
232 mImaginaryCaretRectInContainerFrame = nsRect();
233 mImaginaryCaretReferenceFrame = nullptr;
234 mZoomLevel = 0.0f;
235 }
236
SetPosition(nsIFrame * aFrame,int32_t aOffset)237 AccessibleCaret::PositionChangedResult AccessibleCaret::SetPosition(
238 nsIFrame* aFrame, int32_t aOffset) {
239 if (!CustomContentContainerFrame()) {
240 return PositionChangedResult::NotChanged;
241 }
242
243 nsRect imaginaryCaretRectInFrame =
244 nsCaret::GetGeometryForFrame(aFrame, aOffset, nullptr);
245
246 imaginaryCaretRectInFrame =
247 nsLayoutUtils::ClampRectToScrollFrames(aFrame, imaginaryCaretRectInFrame);
248
249 if (imaginaryCaretRectInFrame.IsEmpty()) {
250 // Don't bother to set the caret position since it's invisible.
251 ClearCachedData();
252 return PositionChangedResult::Invisible;
253 }
254
255 // SetCaretElementStyle() requires the input rect relative to the custom
256 // content container frame.
257 nsRect imaginaryCaretRectInContainerFrame = imaginaryCaretRectInFrame;
258 nsLayoutUtils::TransformRect(aFrame, CustomContentContainerFrame(),
259 imaginaryCaretRectInContainerFrame);
260 const float zoomLevel = GetZoomLevel();
261 const bool isSamePosition = imaginaryCaretRectInContainerFrame.IsEqualEdges(
262 mImaginaryCaretRectInContainerFrame);
263 const bool isSameZoomLevel = FuzzyEqualsMultiplicative(zoomLevel, mZoomLevel);
264
265 // Always update cached mImaginaryCaretRect (relative to the root frame)
266 // because it can change when the caret is scrolled.
267 mImaginaryCaretRect = imaginaryCaretRectInFrame;
268 nsLayoutUtils::TransformRect(aFrame, RootFrame(), mImaginaryCaretRect);
269
270 if (isSamePosition && isSameZoomLevel) {
271 return PositionChangedResult::NotChanged;
272 }
273
274 mImaginaryCaretRectInContainerFrame = imaginaryCaretRectInContainerFrame;
275 mImaginaryCaretReferenceFrame = aFrame;
276 mZoomLevel = zoomLevel;
277
278 SetCaretElementStyle(imaginaryCaretRectInContainerFrame, mZoomLevel);
279
280 return isSamePosition ? PositionChangedResult::Zoom
281 : PositionChangedResult::Position;
282 }
283
RootFrame() const284 nsIFrame* AccessibleCaret::RootFrame() const {
285 return mPresShell->GetRootFrame();
286 }
287
CustomContentContainerFrame() const288 nsIFrame* AccessibleCaret::CustomContentContainerFrame() const {
289 nsCanvasFrame* canvasFrame = mPresShell->GetCanvasFrame();
290 Element* container = canvasFrame->GetCustomContentContainer();
291 nsIFrame* containerFrame = container->GetPrimaryFrame();
292 return containerFrame;
293 }
294
SetCaretElementStyle(const nsRect & aRect,float aZoomLevel)295 void AccessibleCaret::SetCaretElementStyle(const nsRect& aRect,
296 float aZoomLevel) {
297 nsPoint position = CaretElementPosition(aRect);
298 nsAutoString styleStr;
299 // We can't use AppendPrintf here, because it does locale-specific
300 // formatting of floating-point values.
301 styleStr.AppendLiteral("left: ");
302 styleStr.AppendFloat(nsPresContext::AppUnitsToFloatCSSPixels(position.x));
303 styleStr.AppendLiteral("px; top: ");
304 styleStr.AppendFloat(nsPresContext::AppUnitsToFloatCSSPixels(position.y));
305 styleStr.AppendLiteral("px; width: ");
306 styleStr.AppendFloat(StaticPrefs::layout_accessiblecaret_width() /
307 aZoomLevel);
308 styleStr.AppendLiteral("px; margin-left: ");
309 styleStr.AppendFloat(StaticPrefs::layout_accessiblecaret_margin_left() /
310 aZoomLevel);
311 styleStr.AppendLiteral("px; transition-duration: ");
312 styleStr.AppendFloat(
313 StaticPrefs::layout_accessiblecaret_transition_duration());
314 styleStr.AppendLiteral("ms");
315
316 CaretElement().SetAttr(kNameSpaceID_None, nsGkAtoms::style, styleStr, true);
317 AC_LOG("%s: %s", __FUNCTION__, NS_ConvertUTF16toUTF8(styleStr).get());
318
319 // Set style string for children.
320 SetTextOverlayElementStyle(aRect, aZoomLevel);
321 SetCaretImageElementStyle(aRect, aZoomLevel);
322 }
323
SetTextOverlayElementStyle(const nsRect & aRect,float aZoomLevel)324 void AccessibleCaret::SetTextOverlayElementStyle(const nsRect& aRect,
325 float aZoomLevel) {
326 nsAutoString styleStr;
327 styleStr.AppendLiteral("height: ");
328 styleStr.AppendFloat(nsPresContext::AppUnitsToFloatCSSPixels(aRect.height));
329 styleStr.AppendLiteral("px;");
330 TextOverlayElement()->SetAttr(kNameSpaceID_None, nsGkAtoms::style, styleStr,
331 true);
332 AC_LOG("%s: %s", __FUNCTION__, NS_ConvertUTF16toUTF8(styleStr).get());
333 }
334
SetCaretImageElementStyle(const nsRect & aRect,float aZoomLevel)335 void AccessibleCaret::SetCaretImageElementStyle(const nsRect& aRect,
336 float aZoomLevel) {
337 nsAutoString styleStr;
338 styleStr.AppendLiteral("height: ");
339 styleStr.AppendFloat(StaticPrefs::layout_accessiblecaret_height() /
340 aZoomLevel);
341 styleStr.AppendLiteral("px;");
342 CaretImageElement()->SetAttr(kNameSpaceID_None, nsGkAtoms::style, styleStr,
343 true);
344 AC_LOG("%s: %s", __FUNCTION__, NS_ConvertUTF16toUTF8(styleStr).get());
345 }
346
GetZoomLevel()347 float AccessibleCaret::GetZoomLevel() {
348 // Full zoom on desktop.
349 float fullZoom = mPresShell->GetPresContext()->GetFullZoom();
350
351 // Pinch-zoom on fennec.
352 float resolution = mPresShell->GetCumulativeResolution();
353
354 return fullZoom * resolution;
355 }
356
357 } // namespace mozilla
358