TextComposition.cpp
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 sw=2 et 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 "ContentEventHandler.h"
#include "nsContentUtils.h"
#include "nsIContent.h"
#include "nsIEditor.h"
#include "nsIPresShell.h"
#include "nsPresContext.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/EventDispatcher.h"
#include "mozilla/IMEStateManager.h"
#include "mozilla/MiscEvents.h"
#include "mozilla/TextComposition.h"
#include "mozilla/TextEvents.h"
using namespace mozilla::widget;
namespace mozilla {
#define IDEOGRAPHIC_SPACE (NS_LITERAL_STRING("\x3000"))
/******************************************************************************
* TextComposition
******************************************************************************/
TextComposition::TextComposition(nsPresContext* aPresContext,
nsINode* aNode,
WidgetCompositionEvent* aCompositionEvent)
: mPresContext(aPresContext)
, mNode(aNode)
, mNativeContext(
aCompositionEvent->widget->GetInputContext().mNativeIMEContext)
, mCompositionStartOffset(0)
, mCompositionTargetOffset(0)
, mIsSynthesizedForTests(aCompositionEvent->mFlags.mIsSynthesizedForTests)
, mIsComposing(false)
, mIsEditorHandlingEvent(false)
, mIsRequestingCommit(false)
, mIsRequestingCancel(false)
, mRequestedToCommitOrCancel(false)
, mWasNativeCompositionEndEventDiscarded(false)
{
}
void
TextComposition::Destroy()
{
mPresContext = nullptr;
mNode = nullptr;
// TODO: If the editor is still alive and this is held by it, we should tell
// this being destroyed for cleaning up the stuff.
}
bool
TextComposition::MatchesNativeContext(nsIWidget* aWidget) const
{
return mNativeContext == aWidget->GetInputContext().mNativeIMEContext;
}
bool
TextComposition::IsValidStateForComposition(nsIWidget* aWidget) const
{
return !Destroyed() && aWidget && !aWidget->Destroyed() &&
mPresContext->GetPresShell() &&
!mPresContext->GetPresShell()->IsDestroying();
}
bool
TextComposition::MaybeDispatchCompositionUpdate(
const WidgetCompositionEvent* aCompositionEvent)
{
if (!IsValidStateForComposition(aCompositionEvent->widget)) {
return false;
}
if (mLastData == aCompositionEvent->mData) {
return true;
}
CloneAndDispatchAs(aCompositionEvent, NS_COMPOSITION_UPDATE);
return IsValidStateForComposition(aCompositionEvent->widget);
}
BaseEventFlags
TextComposition::CloneAndDispatchAs(
const WidgetCompositionEvent* aCompositionEvent,
uint32_t aMessage,
nsEventStatus* aStatus,
EventDispatchingCallback* aCallBack)
{
MOZ_ASSERT(IsValidStateForComposition(aCompositionEvent->widget),
"Should be called only when it's safe to dispatch an event");
WidgetCompositionEvent compositionEvent(aCompositionEvent->mFlags.mIsTrusted,
aMessage, aCompositionEvent->widget);
compositionEvent.time = aCompositionEvent->time;
compositionEvent.timeStamp = aCompositionEvent->timeStamp;
compositionEvent.mData = aCompositionEvent->mData;
compositionEvent.mFlags.mIsSynthesizedForTests =
aCompositionEvent->mFlags.mIsSynthesizedForTests;
nsEventStatus dummyStatus = nsEventStatus_eConsumeNoDefault;
nsEventStatus* status = aStatus ? aStatus : &dummyStatus;
if (aMessage == NS_COMPOSITION_UPDATE) {
mLastData = compositionEvent.mData;
}
EventDispatcher::Dispatch(mNode, mPresContext,
&compositionEvent, nullptr, status, aCallBack);
return compositionEvent.mFlags;
}
void
TextComposition::OnCompositionEventDiscarded(
const WidgetCompositionEvent* aCompositionEvent)
{
// Note that this method is never called for synthesized events for emulating
// commit or cancel composition.
MOZ_ASSERT(aCompositionEvent->mFlags.mIsTrusted,
"Shouldn't be called with untrusted event");
// XXX If composition events are discarded, should we dispatch them with
// runnable event? However, even if we do so, it might make native IME
// confused due to async modification. Especially when native IME is
// TSF.
if (!aCompositionEvent->CausesDOMCompositionEndEvent()) {
return;
}
mWasNativeCompositionEndEventDiscarded = true;
}
void
TextComposition::DispatchCompositionEvent(
WidgetCompositionEvent* aCompositionEvent,
nsEventStatus* aStatus,
EventDispatchingCallback* aCallBack,
bool aIsSynthesized)
{
if (aCompositionEvent->message == NS_COMPOSITION_COMMIT_AS_IS) {
NS_ASSERTION(!aCompositionEvent->mRanges,
"mRanges of NS_COMPOSITION_COMMIT_AS_IS should be null");
aCompositionEvent->mRanges = nullptr;
NS_ASSERTION(aCompositionEvent->mData.IsEmpty(),
"mData of NS_COMPOSITION_COMMIT_AS_IS should be empty string");
if (mLastData == IDEOGRAPHIC_SPACE) {
// If the last data is an ideographic space (FullWidth space), it must be
// a placeholder character of some Chinese IME. So, committing with
// this data must not be expected by users. Let's use empty string.
aCompositionEvent->mData.Truncate();
} else {
aCompositionEvent->mData = mLastData;
}
} else if (aCompositionEvent->message == NS_COMPOSITION_COMMIT) {
NS_ASSERTION(!aCompositionEvent->mRanges,
"mRanges of NS_COMPOSITION_COMMIT should be null");
aCompositionEvent->mRanges = nullptr;
}
if (!IsValidStateForComposition(aCompositionEvent->widget)) {
*aStatus = nsEventStatus_eConsumeNoDefault;
return;
}
// If this instance has requested to commit or cancel composition but
// is not synthesizing commit event, that means that the IME commits or
// cancels the composition asynchronously. Typically, iBus behaves so.
// Then, synthesized events which were dispatched immediately after
// the request has already committed our editor's composition string and
// told it to web apps. Therefore, we should ignore the delayed events.
if (mRequestedToCommitOrCancel && !aIsSynthesized) {
*aStatus = nsEventStatus_eConsumeNoDefault;
return;
}
// IME may commit composition with empty string for a commit request or
// with non-empty string for a cancel request. We should prevent such
// unexpected result. E.g., web apps may be confused if they implement
// autocomplete which attempts to commit composition forcibly when the user
// selects one of suggestions but composition string is cleared by IME.
// Note that most Chinese IMEs don't expose actual composition string to us.
// They typically tell us an IDEOGRAPHIC SPACE or empty string as composition
// string. Therefore, we should hack it only when:
// 1. committing string is empty string at requesting commit but the last
// data isn't IDEOGRAPHIC SPACE.
// 2. non-empty string is committed at requesting cancel.
if (!aIsSynthesized && (mIsRequestingCommit || mIsRequestingCancel)) {
nsString* committingData = nullptr;
switch (aCompositionEvent->message) {
case NS_COMPOSITION_END:
case NS_COMPOSITION_CHANGE:
case NS_COMPOSITION_COMMIT_AS_IS:
case NS_COMPOSITION_COMMIT:
committingData = &aCompositionEvent->mData;
break;
default:
NS_WARNING("Unexpected event comes during committing or "
"canceling composition");
break;
}
if (committingData) {
if (mIsRequestingCommit && committingData->IsEmpty() &&
mLastData != IDEOGRAPHIC_SPACE) {
committingData->Assign(mLastData);
} else if (mIsRequestingCancel && !committingData->IsEmpty()) {
committingData->Truncate();
}
}
}
bool dispatchEvent = true;
bool dispatchDOMTextEvent = aCompositionEvent->CausesDOMTextEvent();
// When mIsComposing is false but the committing string is different from
// the last data (E.g., previous NS_COMPOSITION_CHANGE event made the
// composition string empty or didn't have clause information), we don't
// need to dispatch redundant DOM text event.
if (dispatchDOMTextEvent &&
aCompositionEvent->message != NS_COMPOSITION_CHANGE &&
!mIsComposing && mLastData == aCompositionEvent->mData) {
dispatchEvent = dispatchDOMTextEvent = false;
}
if (dispatchDOMTextEvent) {
if (!MaybeDispatchCompositionUpdate(aCompositionEvent)) {
return;
}
}
if (dispatchEvent) {
// If the composition event should cause a DOM text event, we should
// overwrite the event message as NS_COMPOSITION_CHANGE because due to
// the limitation of mapping between event messages and DOM event types,
// we cannot map multiple event messages to a DOM event type.
if (dispatchDOMTextEvent &&
aCompositionEvent->message != NS_COMPOSITION_CHANGE) {
aCompositionEvent->mFlags =
CloneAndDispatchAs(aCompositionEvent, NS_COMPOSITION_CHANGE,
aStatus, aCallBack);
} else {
EventDispatcher::Dispatch(mNode, mPresContext,
aCompositionEvent, nullptr, aStatus, aCallBack);
}
} else {
*aStatus = nsEventStatus_eConsumeNoDefault;
}
if (!IsValidStateForComposition(aCompositionEvent->widget)) {
return;
}
// Emulate editor behavior of compositionchange event (DOM text event) handler
// if no editor handles composition events.
if (dispatchDOMTextEvent && !HasEditor()) {
EditorWillHandleCompositionChangeEvent(aCompositionEvent);
EditorDidHandleCompositionChangeEvent();
}
if (aCompositionEvent->CausesDOMCompositionEndEvent()) {
// Dispatch a compositionend event if it's necessary.
if (aCompositionEvent->message != NS_COMPOSITION_END) {
CloneAndDispatchAs(aCompositionEvent, NS_COMPOSITION_END);
}
MOZ_ASSERT(!mIsComposing, "Why is the editor still composing?");
MOZ_ASSERT(!HasEditor(), "Why does the editor still keep to hold this?");
}
// Notify composition update to widget if possible
NotityUpdateComposition(aCompositionEvent);
}
void
TextComposition::NotityUpdateComposition(
const WidgetCompositionEvent* aCompositionEvent)
{
nsEventStatus status;
// When compositon start, notify the rect of first offset character.
// When not compositon start, notify the rect of selected composition
// string if compositionchange event.
if (aCompositionEvent->message == NS_COMPOSITION_START) {
nsCOMPtr<nsIWidget> widget = mPresContext->GetRootWidget();
// Update composition start offset
WidgetQueryContentEvent selectedTextEvent(true,
NS_QUERY_SELECTED_TEXT,
widget);
widget->DispatchEvent(&selectedTextEvent, status);
if (selectedTextEvent.mSucceeded) {
mCompositionStartOffset = selectedTextEvent.mReply.mOffset;
} else {
// Unknown offset
NS_WARNING("Cannot get start offset of IME composition");
mCompositionStartOffset = 0;
}
mCompositionTargetOffset = mCompositionStartOffset;
} else if (aCompositionEvent->CausesDOMTextEvent()) {
mCompositionTargetOffset =
mCompositionStartOffset + aCompositionEvent->TargetClauseOffset();
} else {
return;
}
NotifyIME(NOTIFY_IME_OF_COMPOSITION_UPDATE);
}
void
TextComposition::DispatchCompositionEventRunnable(uint32_t aEventMessage,
const nsAString& aData,
bool aIsSynthesizingCommit)
{
nsContentUtils::AddScriptRunner(
new CompositionEventDispatcher(this, mNode, aEventMessage, aData,
aIsSynthesizingCommit));
}
nsresult
TextComposition::RequestToCommit(nsIWidget* aWidget, bool aDiscard)
{
// If this composition is already requested to be committed or canceled,
// we don't need to request it again because even if the first request
// failed, new request won't success, probably. And we shouldn't synthesize
// events for committing or canceling composition twice or more times.
if (mRequestedToCommitOrCancel) {
return NS_OK;
}
nsRefPtr<TextComposition> kungFuDeathGrip(this);
const nsAutoString lastData(mLastData);
{
AutoRestore<bool> saveRequestingCancel(mIsRequestingCancel);
AutoRestore<bool> saveRequestingCommit(mIsRequestingCommit);
if (aDiscard) {
mIsRequestingCancel = true;
mIsRequestingCommit = false;
} else {
mIsRequestingCancel = false;
mIsRequestingCommit = true;
}
if (!mIsSynthesizedForTests) {
// FYI: CompositionEvents caused by a call of NotifyIME() may be
// discarded by PresShell if it's not safe to dispatch the event.
nsresult rv =
aWidget->NotifyIME(IMENotification(aDiscard ?
REQUEST_TO_CANCEL_COMPOSITION :
REQUEST_TO_COMMIT_COMPOSITION));
if (rv == NS_ERROR_NOT_IMPLEMENTED) {
return rv;
}
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
} else {
// Emulates to commit or cancel the composition
// FYI: These events may be discarded by PresShell if it's not safe to
// dispatch the event.
nsCOMPtr<nsIWidget> widget(aWidget);
nsAutoString commitData(aDiscard ? EmptyString() : lastData);
bool isChanging = commitData != mLastData;
uint32_t message =
isChanging ? NS_COMPOSITION_COMMIT : NS_COMPOSITION_COMMIT_AS_IS;
WidgetCompositionEvent commitEvent(true, message, widget);
if (commitEvent.message == NS_COMPOSITION_COMMIT) {
commitEvent.mData = commitData;
}
commitEvent.mFlags.mIsSynthesizedForTests = true;
nsEventStatus status = nsEventStatus_eIgnore;
widget->DispatchEvent(&commitEvent, status);
}
}
mRequestedToCommitOrCancel = true;
// If the request is performed synchronously, this must be already destroyed.
if (Destroyed()) {
return NS_OK;
}
// Otherwise, synthesize the commit in content.
nsAutoString data(aDiscard ? EmptyString() : lastData);
if (data == mLastData) {
DispatchCompositionEventRunnable(NS_COMPOSITION_COMMIT_AS_IS, EmptyString(),
true);
} else {
DispatchCompositionEventRunnable(NS_COMPOSITION_COMMIT, data, true);
}
return NS_OK;
}
nsresult
TextComposition::NotifyIME(IMEMessage aMessage)
{
NS_ENSURE_TRUE(mPresContext, NS_ERROR_NOT_AVAILABLE);
return IMEStateManager::NotifyIME(aMessage, mPresContext);
}
void
TextComposition::EditorWillHandleCompositionChangeEvent(
const WidgetCompositionEvent* aCompositionChangeEvent)
{
mIsComposing = aCompositionChangeEvent->IsComposing();
mRanges = aCompositionChangeEvent->mRanges;
mIsEditorHandlingEvent = true;
MOZ_ASSERT(mLastData == aCompositionChangeEvent->mData,
"The text of a compositionchange event must be same as previous data "
"attribute value of the latest compositionupdate event");
}
void
TextComposition::EditorDidHandleCompositionChangeEvent()
{
mString = mLastData;
mIsEditorHandlingEvent = false;
}
void
TextComposition::StartHandlingComposition(nsIEditor* aEditor)
{
MOZ_ASSERT(!HasEditor(), "There is a handling editor already");
mEditorWeak = do_GetWeakReference(aEditor);
}
void
TextComposition::EndHandlingComposition(nsIEditor* aEditor)
{
#ifdef DEBUG
nsCOMPtr<nsIEditor> editor = GetEditor();
MOZ_ASSERT(editor == aEditor, "Another editor handled the composition?");
#endif // #ifdef DEBUG
mEditorWeak = nullptr;
}
already_AddRefed<nsIEditor>
TextComposition::GetEditor() const
{
nsCOMPtr<nsIEditor> editor = do_QueryReferent(mEditorWeak);
return editor.forget();
}
bool
TextComposition::HasEditor() const
{
nsCOMPtr<nsIEditor> editor = GetEditor();
return !!editor;
}
/******************************************************************************
* TextComposition::CompositionEventDispatcher
******************************************************************************/
TextComposition::CompositionEventDispatcher::CompositionEventDispatcher(
TextComposition* aComposition,
nsINode* aEventTarget,
uint32_t aEventMessage,
const nsAString& aData,
bool aIsSynthesizedEvent)
: mTextComposition(aComposition)
, mEventTarget(aEventTarget)
, mEventMessage(aEventMessage)
, mData(aData)
, mIsSynthesizedEvent(aIsSynthesizedEvent)
{
}
NS_IMETHODIMP
TextComposition::CompositionEventDispatcher::Run()
{
// The widget can be different from the widget which has dispatched
// composition events because GetWidget() returns a widget which is proper
// for calling NotifyIME(). However, this must no be problem since both
// widget should share native IME context. Therefore, even if an event
// handler uses the widget for requesting IME to commit or cancel, it works.
nsCOMPtr<nsIWidget> widget(mTextComposition->GetWidget());
if (!mTextComposition->IsValidStateForComposition(widget)) {
return NS_OK; // cannot dispatch any events anymore
}
nsRefPtr<nsPresContext> presContext = mTextComposition->mPresContext;
nsEventStatus status = nsEventStatus_eIgnore;
switch (mEventMessage) {
case NS_COMPOSITION_START: {
WidgetCompositionEvent compStart(true, NS_COMPOSITION_START, widget);
WidgetQueryContentEvent selectedText(true, NS_QUERY_SELECTED_TEXT,
widget);
ContentEventHandler handler(presContext);
handler.OnQuerySelectedText(&selectedText);
NS_ASSERTION(selectedText.mSucceeded, "Failed to get selected text");
compStart.mData = selectedText.mReply.mString;
compStart.mFlags.mIsSynthesizedForTests =
mTextComposition->IsSynthesizedForTests();
IMEStateManager::DispatchCompositionEvent(mEventTarget, presContext,
&compStart, &status, nullptr,
mIsSynthesizedEvent);
break;
}
case NS_COMPOSITION_CHANGE:
case NS_COMPOSITION_COMMIT_AS_IS:
case NS_COMPOSITION_COMMIT: {
WidgetCompositionEvent compEvent(true, mEventMessage, widget);
if (mEventMessage != NS_COMPOSITION_COMMIT_AS_IS) {
compEvent.mData = mData;
}
compEvent.mFlags.mIsSynthesizedForTests =
mTextComposition->IsSynthesizedForTests();
IMEStateManager::DispatchCompositionEvent(mEventTarget, presContext,
&compEvent, &status, nullptr,
mIsSynthesizedEvent);
break;
}
default:
MOZ_CRASH("Unsupported event");
}
return NS_OK;
}
/******************************************************************************
* TextCompositionArray
******************************************************************************/
TextCompositionArray::index_type
TextCompositionArray::IndexOf(nsIWidget* aWidget)
{
for (index_type i = Length(); i > 0; --i) {
if (ElementAt(i - 1)->MatchesNativeContext(aWidget)) {
return i - 1;
}
}
return NoIndex;
}
TextCompositionArray::index_type
TextCompositionArray::IndexOf(nsPresContext* aPresContext)
{
for (index_type i = Length(); i > 0; --i) {
if (ElementAt(i - 1)->GetPresContext() == aPresContext) {
return i - 1;
}
}
return NoIndex;
}
TextCompositionArray::index_type
TextCompositionArray::IndexOf(nsPresContext* aPresContext,
nsINode* aNode)
{
index_type index = IndexOf(aPresContext);
if (index == NoIndex) {
return NoIndex;
}
nsINode* node = ElementAt(index)->GetEventTargetNode();
return node == aNode ? index : NoIndex;
}
TextComposition*
TextCompositionArray::GetCompositionFor(nsIWidget* aWidget)
{
index_type i = IndexOf(aWidget);
return i != NoIndex ? ElementAt(i) : nullptr;
}
TextComposition*
TextCompositionArray::GetCompositionFor(nsPresContext* aPresContext,
nsINode* aNode)
{
index_type i = IndexOf(aPresContext, aNode);
return i != NoIndex ? ElementAt(i) : nullptr;
}
TextComposition*
TextCompositionArray::GetCompositionInContent(nsPresContext* aPresContext,
nsIContent* aContent)
{
// There should be only one composition per content object.
for (index_type i = Length(); i > 0; --i) {
nsINode* node = ElementAt(i - 1)->GetEventTargetNode();
if (node && nsContentUtils::ContentIsDescendantOf(node, aContent)) {
return ElementAt(i - 1);
}
}
return nullptr;
}
} // namespace mozilla
