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/* -*- 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/. */
#include "AccessibleCaret.h"
#include "AccessibleCaretLogger.h"
#include "mozilla/FloatingPoint.h"
#include "mozilla/PresShell.h"
#include "mozilla/StaticPrefs_layout.h"
#include "mozilla/ToString.h"
#include "nsCanvasFrame.h"
#include "nsCaret.h"
#include "nsCSSFrameConstructor.h"
#include "nsDOMTokenList.h"
#include "nsIFrame.h"
#include "nsPlaceholderFrame.h"
namespace mozilla {
using namespace dom;
#undef AC_LOG
#define AC_LOG(message, ...) \
AC_LOG_BASE("AccessibleCaret (%p): " message, this, ##__VA_ARGS__);
#undef AC_LOGV
#define AC_LOGV(message, ...) \
AC_LOGV_BASE("AccessibleCaret (%p): " message, this, ##__VA_ARGS__);
NS_IMPL_ISUPPORTS(AccessibleCaret::DummyTouchListener, nsIDOMEventListener)
const nsLiteralString AccessibleCaret::sTextOverlayElementId =
u"text-overlay"_ns;
const nsLiteralString AccessibleCaret::sCaretImageElementId = u"image"_ns;
#define AC_PROCESS_ENUM_TO_STREAM(e) \
case (e): \
aStream << #e; \
break;
std::ostream& operator<<(std::ostream& aStream,
const AccessibleCaret::Appearance& aAppearance) {
using Appearance = AccessibleCaret::Appearance;
switch (aAppearance) {
AC_PROCESS_ENUM_TO_STREAM(Appearance::None);
AC_PROCESS_ENUM_TO_STREAM(Appearance::Normal);
AC_PROCESS_ENUM_TO_STREAM(Appearance::NormalNotShown);
AC_PROCESS_ENUM_TO_STREAM(Appearance::Left);
AC_PROCESS_ENUM_TO_STREAM(Appearance::Right);
}
return aStream;
}
std::ostream& operator<<(
std::ostream& aStream,
const AccessibleCaret::PositionChangedResult& aResult) {
using PositionChangedResult = AccessibleCaret::PositionChangedResult;
switch (aResult) {
AC_PROCESS_ENUM_TO_STREAM(PositionChangedResult::NotChanged);
AC_PROCESS_ENUM_TO_STREAM(PositionChangedResult::Position);
AC_PROCESS_ENUM_TO_STREAM(PositionChangedResult::Zoom);
AC_PROCESS_ENUM_TO_STREAM(PositionChangedResult::Invisible);
}
return aStream;
}
#undef AC_PROCESS_ENUM_TO_STREAM
// -----------------------------------------------------------------------------
// Implementation of AccessibleCaret methods
AccessibleCaret::AccessibleCaret(PresShell* aPresShell)
: mPresShell(aPresShell) {
// Check all resources required.
if (mPresShell) {
MOZ_ASSERT(RootFrame());
MOZ_ASSERT(mPresShell->GetDocument());
InjectCaretElement(mPresShell->GetDocument());
}
}
AccessibleCaret::~AccessibleCaret() {
if (mPresShell) {
RemoveCaretElement(mPresShell->GetDocument());
}
}
void AccessibleCaret::SetAppearance(Appearance aAppearance) {
if (mAppearance == aAppearance) {
return;
}
ErrorResult rv;
CaretElement().ClassList()->Remove(AppearanceString(mAppearance), rv);
MOZ_ASSERT(!rv.Failed(), "Remove old appearance failed!");
CaretElement().ClassList()->Add(AppearanceString(aAppearance), rv);
MOZ_ASSERT(!rv.Failed(), "Add new appearance failed!");
AC_LOG("%s: %s -> %s", __FUNCTION__, ToString(mAppearance).c_str(),
ToString(aAppearance).c_str());
mAppearance = aAppearance;
// Need to reset rect since the cached rect will be compared in SetPosition.
if (mAppearance == Appearance::None) {
ClearCachedData();
}
}
/* static */
nsAutoString AccessibleCaret::AppearanceString(Appearance aAppearance) {
nsAutoString string;
switch (aAppearance) {
case Appearance::None:
case Appearance::NormalNotShown:
string = u"none"_ns;
break;
case Appearance::Normal:
string = u"normal"_ns;
break;
case Appearance::Right:
string = u"right"_ns;
break;
case Appearance::Left:
string = u"left"_ns;
break;
}
return string;
}
bool AccessibleCaret::Intersects(const AccessibleCaret& aCaret) const {
MOZ_ASSERT(mPresShell == aCaret.mPresShell);
if (!IsVisuallyVisible() || !aCaret.IsVisuallyVisible()) {
return false;
}
nsRect rect =
nsLayoutUtils::GetRectRelativeToFrame(&CaretElement(), RootFrame());
nsRect rhsRect = nsLayoutUtils::GetRectRelativeToFrame(&aCaret.CaretElement(),
RootFrame());
return rect.Intersects(rhsRect);
}
bool AccessibleCaret::Contains(const nsPoint& aPoint,
TouchArea aTouchArea) const {
if (!IsVisuallyVisible()) {
return false;
}
nsRect textOverlayRect =
nsLayoutUtils::GetRectRelativeToFrame(TextOverlayElement(), RootFrame());
nsRect caretImageRect =
nsLayoutUtils::GetRectRelativeToFrame(CaretImageElement(), RootFrame());
if (aTouchArea == TouchArea::CaretImage) {
return caretImageRect.Contains(aPoint);
}
MOZ_ASSERT(aTouchArea == TouchArea::Full, "Unexpected TouchArea type!");
return textOverlayRect.Contains(aPoint) || caretImageRect.Contains(aPoint);
}
void AccessibleCaret::EnsureApzAware() {
// If the caret element was cloned, the listener might have been lost. So
// if that's the case we register a dummy listener if there isn't one on
// the element already.
if (!CaretElement().IsApzAware()) {
// FIXME(emilio): Is this needed anymore?
CaretElement().AddEventListener(u"touchstart"_ns, mDummyTouchListener,
false);
}
}
bool AccessibleCaret::IsInPositionFixedSubtree() const {
return nsLayoutUtils::IsInPositionFixedSubtree(
mImaginaryCaretReferenceFrame.GetFrame());
}
void AccessibleCaret::InjectCaretElement(Document* aDocument) {
ErrorResult rv;
RefPtr<Element> element = CreateCaretElement(aDocument);
mCaretElementHolder = aDocument->InsertAnonymousContent(*element, rv);
MOZ_ASSERT(!rv.Failed(), "Insert anonymous content should not fail!");
MOZ_ASSERT(mCaretElementHolder, "We must have anonymous content!");
// InsertAnonymousContent will clone the element to make an AnonymousContent.
// Since event listeners are not being cloned when cloning a node, we need to
// add the listener here.
EnsureApzAware();
}
already_AddRefed<Element> AccessibleCaret::CreateCaretElement(
Document* aDocument) const {
// Content structure of AccessibleCaret
// <div class="moz-accessiblecaret"> <- CaretElement()
// <div id="text-overlay"> <- TextOverlayElement()
// <div id="image"> <- CaretImageElement()
ErrorResult rv;
RefPtr<Element> parent = aDocument->CreateHTMLElement(nsGkAtoms::div);
parent->ClassList()->Add(u"moz-accessiblecaret"_ns, rv);
parent->ClassList()->Add(u"none"_ns, rv);
auto CreateAndAppendChildElement =
[aDocument, &parent](const nsLiteralString& aElementId) {
RefPtr<Element> child = aDocument->CreateHTMLElement(nsGkAtoms::div);
child->SetAttr(kNameSpaceID_None, nsGkAtoms::id, aElementId, true);
parent->AppendChildTo(child, false);
};
CreateAndAppendChildElement(sTextOverlayElementId);
CreateAndAppendChildElement(sCaretImageElementId);
return parent.forget();
}
void AccessibleCaret::RemoveCaretElement(Document* aDocument) {
CaretElement().RemoveEventListener(u"touchstart"_ns, mDummyTouchListener,
false);
aDocument->RemoveAnonymousContent(*mCaretElementHolder, IgnoreErrors());
}
void AccessibleCaret::ClearCachedData() {
mImaginaryCaretRect = nsRect();
mImaginaryCaretRectInContainerFrame = nsRect();
mImaginaryCaretReferenceFrame = nullptr;
mZoomLevel = 0.0f;
}
AccessibleCaret::PositionChangedResult AccessibleCaret::SetPosition(
nsIFrame* aFrame, int32_t aOffset) {
if (!CustomContentContainerFrame()) {
return PositionChangedResult::NotChanged;
}
nsRect imaginaryCaretRectInFrame =
nsCaret::GetGeometryForFrame(aFrame, aOffset, nullptr);
imaginaryCaretRectInFrame =
nsLayoutUtils::ClampRectToScrollFrames(aFrame, imaginaryCaretRectInFrame);
if (imaginaryCaretRectInFrame.IsEmpty()) {
// Don't bother to set the caret position since it's invisible.
ClearCachedData();
return PositionChangedResult::Invisible;
}
// SetCaretElementStyle() requires the input rect relative to the custom
// content container frame.
nsRect imaginaryCaretRectInContainerFrame = imaginaryCaretRectInFrame;
nsLayoutUtils::TransformRect(aFrame, CustomContentContainerFrame(),
imaginaryCaretRectInContainerFrame);
const float zoomLevel = GetZoomLevel();
const bool isSamePosition = imaginaryCaretRectInContainerFrame.IsEqualEdges(
mImaginaryCaretRectInContainerFrame);
const bool isSameZoomLevel = FuzzyEqualsMultiplicative(zoomLevel, mZoomLevel);
// Always update cached mImaginaryCaretRect (relative to the root frame)
// because it can change when the caret is scrolled.
mImaginaryCaretRect = imaginaryCaretRectInFrame;
nsLayoutUtils::TransformRect(aFrame, RootFrame(), mImaginaryCaretRect);
if (isSamePosition && isSameZoomLevel) {
return PositionChangedResult::NotChanged;
}
mImaginaryCaretRectInContainerFrame = imaginaryCaretRectInContainerFrame;
mImaginaryCaretReferenceFrame = aFrame;
mZoomLevel = zoomLevel;
SetCaretElementStyle(imaginaryCaretRectInContainerFrame, mZoomLevel);
return isSamePosition ? PositionChangedResult::Zoom
: PositionChangedResult::Position;
}
nsIFrame* AccessibleCaret::CustomContentContainerFrame() const {
nsCanvasFrame* canvasFrame = mPresShell->GetCanvasFrame();
Element* container = canvasFrame->GetCustomContentContainer();
nsIFrame* containerFrame = container->GetPrimaryFrame();
return containerFrame;
}
void AccessibleCaret::SetCaretElementStyle(const nsRect& aRect,
float aZoomLevel) {
nsPoint position = CaretElementPosition(aRect);
nsAutoString styleStr;
// We can't use AppendPrintf here, because it does locale-specific
// formatting of floating-point values.
styleStr.AppendLiteral("left: ");
styleStr.AppendFloat(nsPresContext::AppUnitsToFloatCSSPixels(position.x));
styleStr.AppendLiteral("px; top: ");
styleStr.AppendFloat(nsPresContext::AppUnitsToFloatCSSPixels(position.y));
styleStr.AppendLiteral("px; width: ");
styleStr.AppendFloat(StaticPrefs::layout_accessiblecaret_width() /
aZoomLevel);
styleStr.AppendLiteral("px; margin-left: ");
styleStr.AppendFloat(StaticPrefs::layout_accessiblecaret_margin_left() /
aZoomLevel);
styleStr.AppendLiteral("px");
CaretElement().SetAttr(kNameSpaceID_None, nsGkAtoms::style, styleStr, true);
AC_LOG("%s: %s", __FUNCTION__, NS_ConvertUTF16toUTF8(styleStr).get());
// Set style string for children.
SetTextOverlayElementStyle(aRect, aZoomLevel);
SetCaretImageElementStyle(aRect, aZoomLevel);
}
void AccessibleCaret::SetTextOverlayElementStyle(const nsRect& aRect,
float aZoomLevel) {
nsAutoString styleStr;
styleStr.AppendLiteral("height: ");
styleStr.AppendFloat(nsPresContext::AppUnitsToFloatCSSPixels(aRect.height));
styleStr.AppendLiteral("px;");
TextOverlayElement()->SetAttr(kNameSpaceID_None, nsGkAtoms::style, styleStr,
true);
AC_LOG("%s: %s", __FUNCTION__, NS_ConvertUTF16toUTF8(styleStr).get());
}
void AccessibleCaret::SetCaretImageElementStyle(const nsRect& aRect,
float aZoomLevel) {
nsAutoString styleStr;
styleStr.AppendLiteral("height: ");
styleStr.AppendFloat(StaticPrefs::layout_accessiblecaret_height() /
aZoomLevel);
styleStr.AppendLiteral("px;");
CaretImageElement()->SetAttr(kNameSpaceID_None, nsGkAtoms::style, styleStr,
true);
AC_LOG("%s: %s", __FUNCTION__, NS_ConvertUTF16toUTF8(styleStr).get());
}
float AccessibleCaret::GetZoomLevel() {
// Full zoom on desktop.
float fullZoom = mPresShell->GetPresContext()->GetFullZoom();
// Pinch-zoom on fennec.
float resolution = mPresShell->GetCumulativeResolution();
return fullZoom * resolution;
}
} // namespace mozilla