gecko-dev/editor/libeditor/EditorUtils.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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_EditorUtils_h
#define mozilla_EditorUtils_h
#include "mozilla/EditorBase.h" // for EditorBase
#include "mozilla/EditorDOMPoint.h" // for EditorDOMPoint, EditorDOMRange, etc
#include "mozilla/EditorForwards.h"
#include "mozilla/IntegerRange.h" // for IntegerRange
#include "mozilla/Maybe.h" // for Maybe
#include "mozilla/Result.h" // for Result<>
#include "mozilla/dom/Element.h" // for dom::Element
#include "mozilla/dom/HTMLBRElement.h" // for dom::HTMLBRElement
#include "mozilla/dom/Selection.h" // for dom::Selection
#include "mozilla/dom/Text.h" // for dom::Text
#include "nsAtom.h" // for nsStaticAtom
#include "nsCOMPtr.h" // for nsCOMPtr
#include "nsContentUtils.h" // for nsContentUtils
#include "nsDebug.h" // for NS_WARNING, etc
#include "nsError.h" // for NS_SUCCESS_* and NS_ERROR_*
#include "nsRange.h" // for nsRange
#include "nsString.h" // for nsAString, nsString, etc
class nsITransferable;
namespace mozilla {
enum class StyleWhiteSpace : uint8_t;
enum class SuggestCaret {
// If specified, the method returns NS_OK when there is no recommended caret
// position.
OnlyIfHasSuggestion,
// If specified and if EditorBase::AllowsTransactionsToChangeSelection
// returns false, the method does nothing and returns NS_OK.
OnlyIfTransactionsAllowedToDoIt,
// If specified, the method returns
// NS_SUCCESS_EDITOR_BUT_IGNORED_TRIVIAL_ERROR even if
// EditorBase::CollapseSelectionTo returns an error except when
// NS_ERROR_EDITOR_DESTROYED.
AndIgnoreTrivialError,
};
/******************************************************************************
* CaretPoint is a wrapper of EditorDOMPoint and provides a helper method to
* collapse Selection there, or move it to a local variable. This is typically
* used as the ok type of Result or a base class of DoSomethingResult classes.
******************************************************************************/
class MOZ_STACK_CLASS CaretPoint {
public:
explicit CaretPoint(const EditorDOMPoint& aPointToPutCaret)
: mCaretPoint(aPointToPutCaret) {}
explicit CaretPoint(EditorDOMPoint&& aPointToPutCaret)
: mCaretPoint(std::move(aPointToPutCaret)) {}
CaretPoint(const CaretPoint&) = delete;
CaretPoint& operator=(const CaretPoint&) = delete;
CaretPoint(CaretPoint&&) = default;
CaretPoint& operator=(CaretPoint&&) = default;
/**
* Suggest caret position to aEditorBase.
*/
[[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult SuggestCaretPointTo(
const EditorBase& aEditorBase, const SuggestCaretOptions& aOptions) const;
/**
* IgnoreCaretPointSuggestion() should be called if the method does not want
* to use caret position recommended by this instance.
*/
void IgnoreCaretPointSuggestion() const { mHandledCaretPoint = true; }
/**
* When propagating the result, it may not want to the caller modify
* selection. In such case, this can clear the caret point. Use
* IgnoreCaretPointSuggestion() in the caller side instead.
*/
void ForgetCaretPointSuggestion() { mCaretPoint.Clear(); }
bool HasCaretPointSuggestion() const { return mCaretPoint.IsSet(); }
constexpr const EditorDOMPoint& CaretPointRef() const { return mCaretPoint; }
constexpr EditorDOMPoint&& UnwrapCaretPoint() {
mHandledCaretPoint = true;
return std::move(mCaretPoint);
}
bool CopyCaretPointTo(EditorDOMPoint& aPointToPutCaret,
const SuggestCaretOptions& aOptions) const {
MOZ_ASSERT(!aOptions.contains(SuggestCaret::AndIgnoreTrivialError));
MOZ_ASSERT(
!aOptions.contains(SuggestCaret::OnlyIfTransactionsAllowedToDoIt));
if (aOptions.contains(SuggestCaret::OnlyIfHasSuggestion) &&
!mCaretPoint.IsSet()) {
return false;
}
aPointToPutCaret = mCaretPoint;
return true;
}
bool MoveCaretPointTo(EditorDOMPoint& aPointToPutCaret,
const SuggestCaretOptions& aOptions) {
MOZ_ASSERT(!aOptions.contains(SuggestCaret::AndIgnoreTrivialError));
MOZ_ASSERT(
!aOptions.contains(SuggestCaret::OnlyIfTransactionsAllowedToDoIt));
if (aOptions.contains(SuggestCaret::OnlyIfHasSuggestion) &&
!mCaretPoint.IsSet()) {
return false;
}
aPointToPutCaret = UnwrapCaretPoint();
return true;
}
bool CopyCaretPointTo(EditorDOMPoint& aPointToPutCaret,
const EditorBase& aEditorBase,
const SuggestCaretOptions& aOptions) const;
bool MoveCaretPointTo(EditorDOMPoint& aPointToPutCaret,
const EditorBase& aEditorBase,
const SuggestCaretOptions& aOptions);
protected:
constexpr bool CaretPointHandled() const { return mHandledCaretPoint; }
void SetCaretPoint(const EditorDOMPoint& aCaretPoint) {
mHandledCaretPoint = false;
mCaretPoint = aCaretPoint;
}
void SetCaretPoint(EditorDOMPoint&& aCaretPoint) {
mHandledCaretPoint = false;
mCaretPoint = std::move(aCaretPoint);
}
void UnmarkAsHandledCaretPoint() { mHandledCaretPoint = true; }
CaretPoint() = default;
private:
EditorDOMPoint mCaretPoint;
bool mutable mHandledCaretPoint = false;
};
/***************************************************************************
* EditActionResult is useful to return the handling state of edit sub actions
* without out params.
*/
class MOZ_STACK_CLASS EditActionResult final {
public:
bool Canceled() const { return mCanceled; }
bool Handled() const { return mHandled; }
bool Ignored() const { return !mCanceled && !mHandled; }
void MarkAsCanceled() { mCanceled = true; }
void MarkAsHandled() { mHandled = true; }
EditActionResult& operator|=(const EditActionResult& aOther) {
mCanceled |= aOther.mCanceled;
mHandled |= aOther.mHandled;
return *this;
}
EditActionResult& operator|=(const MoveNodeResult& aMoveNodeResult);
static EditActionResult IgnoredResult() {
return EditActionResult(false, false);
}
static EditActionResult HandledResult() {
return EditActionResult(false, true);
}
static EditActionResult CanceledResult() {
return EditActionResult(true, true);
}
EditActionResult(const EditActionResult&) = delete;
EditActionResult& operator=(const EditActionResult&) = delete;
EditActionResult(EditActionResult&&) = default;
EditActionResult& operator=(EditActionResult&&) = default;
private:
bool mCanceled = false;
bool mHandled = false;
EditActionResult(bool aCanceled, bool aHandled)
: mCanceled(aCanceled), mHandled(aHandled) {}
EditActionResult() : mCanceled(false), mHandled(false) {}
};
/***************************************************************************
* CreateNodeResultBase is a simple class for CreateSomething() methods
* which want to return new node.
*/
template <typename NodeType>
class MOZ_STACK_CLASS CreateNodeResultBase final : public CaretPoint {
using SelfType = CreateNodeResultBase<NodeType>;
public:
bool Handled() const { return mNode; }
NodeType* GetNewNode() const { return mNode; }
RefPtr<NodeType> UnwrapNewNode() { return std::move(mNode); }
CreateNodeResultBase() = delete;
explicit CreateNodeResultBase(NodeType& aNode) : mNode(&aNode) {}
explicit CreateNodeResultBase(NodeType& aNode,
const EditorDOMPoint& aCandidateCaretPoint)
: CaretPoint(aCandidateCaretPoint), mNode(&aNode) {}
explicit CreateNodeResultBase(NodeType& aNode,
EditorDOMPoint&& aCandidateCaretPoint)
: CaretPoint(std::move(aCandidateCaretPoint)), mNode(&aNode) {}
explicit CreateNodeResultBase(RefPtr<NodeType>&& aNode)
: mNode(std::move(aNode)) {}
explicit CreateNodeResultBase(RefPtr<NodeType>&& aNode,
const EditorDOMPoint& aCandidateCaretPoint)
: CaretPoint(aCandidateCaretPoint), mNode(std::move(aNode)) {
MOZ_ASSERT(mNode);
}
explicit CreateNodeResultBase(RefPtr<NodeType>&& aNode,
EditorDOMPoint&& aCandidateCaretPoint)
: CaretPoint(std::move(aCandidateCaretPoint)), mNode(std::move(aNode)) {
MOZ_ASSERT(mNode);
}
[[nodiscard]] static SelfType NotHandled() {
return SelfType(EditorDOMPoint());
}
[[nodiscard]] static SelfType NotHandled(
const EditorDOMPoint& aPointToPutCaret) {
SelfType result(aPointToPutCaret);
return result;
}
[[nodiscard]] static SelfType NotHandled(EditorDOMPoint&& aPointToPutCaret) {
SelfType result(std::move(aPointToPutCaret));
return result;
}
#ifdef DEBUG
~CreateNodeResultBase() {
MOZ_ASSERT(!HasCaretPointSuggestion() || CaretPointHandled());
}
#endif
CreateNodeResultBase(const SelfType& aOther) = delete;
SelfType& operator=(const SelfType& aOther) = delete;
CreateNodeResultBase(SelfType&& aOther) = default;
SelfType& operator=(SelfType&& aOther) = default;
private:
explicit CreateNodeResultBase(const EditorDOMPoint& aCandidateCaretPoint)
: CaretPoint(aCandidateCaretPoint) {}
explicit CreateNodeResultBase(EditorDOMPoint&& aCandidateCaretPoint)
: CaretPoint(std::move(aCandidateCaretPoint)) {}
RefPtr<NodeType> mNode;
};
/***************************************************************************
* stack based helper class for calling EditorBase::EndTransaction() after
* EditorBase::BeginTransaction(). This shouldn't be used in editor classes
* or helper classes while an edit action is being handled. Use
* AutoTransactionBatch in such cases since it uses non-virtual internal
* methods.
***************************************************************************/
class MOZ_RAII AutoTransactionBatchExternal final {
public:
MOZ_CAN_RUN_SCRIPT explicit AutoTransactionBatchExternal(
EditorBase& aEditorBase)
: mEditorBase(aEditorBase) {
MOZ_KnownLive(mEditorBase).BeginTransaction();
}
MOZ_CAN_RUN_SCRIPT ~AutoTransactionBatchExternal() {
MOZ_KnownLive(mEditorBase).EndTransaction();
}
private:
EditorBase& mEditorBase;
};
/******************************************************************************
* AutoSelectionRangeArray stores all ranges in `aSelection`.
* Note that modifying the ranges means modifing the selection ranges.
*****************************************************************************/
class MOZ_STACK_CLASS AutoSelectionRangeArray final {
public:
explicit AutoSelectionRangeArray(dom::Selection& aSelection) {
for (const uint32_t i : IntegerRange(aSelection.RangeCount())) {
MOZ_ASSERT(aSelection.GetRangeAt(i));
mRanges.AppendElement(*aSelection.GetRangeAt(i));
}
}
AutoTArray<mozilla::OwningNonNull<nsRange>, 8> mRanges;
};
class EditorUtils final {
public:
using EditorType = EditorBase::EditorType;
using Selection = dom::Selection;
/**
* IsDescendantOf() checks if aNode is a child or a descendant of aParent.
* aOutPoint is set to the child of aParent.
*
* @return true if aNode is a child or a descendant of aParent.
*/
static bool IsDescendantOf(const nsINode& aNode, const nsINode& aParent,
EditorRawDOMPoint* aOutPoint = nullptr);
static bool IsDescendantOf(const nsINode& aNode, const nsINode& aParent,
EditorDOMPoint* aOutPoint);
/**
* Returns true if aContent is a <br> element and it's marked as padding for
* empty editor.
*/
static bool IsPaddingBRElementForEmptyEditor(const nsIContent& aContent) {
const dom::HTMLBRElement* brElement =
dom::HTMLBRElement::FromNode(&aContent);
return brElement && brElement->IsPaddingForEmptyEditor();
}
/**
* Returns true if aContent is a <br> element and it's marked as padding for
* empty last line.
*/
static bool IsPaddingBRElementForEmptyLastLine(const nsIContent& aContent) {
const dom::HTMLBRElement* brElement =
dom::HTMLBRElement::FromNode(&aContent);
return brElement && brElement->IsPaddingForEmptyLastLine();
}
/**
* IsEditableContent() returns true if aContent's data or children is ediable
* for the given editor type. Be aware, returning true does NOT mean the
* node can be removed from its parent node, and returning false does NOT
* mean the node cannot be removed from the parent node.
* XXX May be the anonymous nodes in TextEditor not editable? If it's not
* so, we can get rid of aEditorType.
*/
static bool IsEditableContent(const nsIContent& aContent,
EditorType aEditorType) {
if (aEditorType == EditorType::HTML &&
(!aContent.IsEditable() || !aContent.IsInComposedDoc())) {
// FIXME(emilio): Why only for HTML editors? All content from the root
// content in text editors is also editable, so afaict we can remove the
// special-case.
return false;
}
return IsElementOrText(aContent);
}
/**
* Returns true if aContent is a usual element node (not padding <br> element
* for empty editor) or a text node. In other words, returns true if
* aContent is a usual element node or visible data node.
*/
static bool IsElementOrText(const nsIContent& aContent) {
if (aContent.IsText()) {
return true;
}
return aContent.IsElement() && !IsPaddingBRElementForEmptyEditor(aContent);
}
/**
* Get computed white-space style of aContent.
*/
static Maybe<StyleWhiteSpace> GetComputedWhiteSpaceStyle(
const nsIContent& aContent);
/**
* IsWhiteSpacePreformatted() checks the style info for the node for the
* preformatted text style. This does NOT flush layout.
*/
static bool IsWhiteSpacePreformatted(const nsIContent& aContent);
/**
* IsNewLinePreformatted() checks whether the linefeed characters are
* preformatted or collapsible white-spaces. This does NOT flush layout.
*/
static bool IsNewLinePreformatted(const nsIContent& aContent);
/**
* IsOnlyNewLinePreformatted() checks whether the linefeed characters are
* preformated but white-spaces are collapsed, or otherwise. I.e., this
* returns true only when `white-space:pre-line`.
*/
static bool IsOnlyNewLinePreformatted(const nsIContent& aContent);
static nsStaticAtom* GetTagNameAtom(const nsAString& aTagName) {
if (aTagName.IsEmpty()) {
return nullptr;
}
nsAutoString lowerTagName;
nsContentUtils::ASCIIToLower(aTagName, lowerTagName);
return NS_GetStaticAtom(lowerTagName);
}
static nsStaticAtom* GetAttributeAtom(const nsAString& aAttribute) {
if (aAttribute.IsEmpty()) {
return nullptr; // Don't use nsGkAtoms::_empty for attribute.
}
return NS_GetStaticAtom(aAttribute);
}
/**
* Helper method for deletion. When this returns true, Selection will be
* computed with nsFrameSelection that also requires flushed layout
* information.
*/
template <typename SelectionOrAutoRangeArray>
static bool IsFrameSelectionRequiredToExtendSelection(
nsIEditor::EDirection aDirectionAndAmount,
SelectionOrAutoRangeArray& aSelectionOrAutoRangeArray) {
switch (aDirectionAndAmount) {
case nsIEditor::eNextWord:
case nsIEditor::ePreviousWord:
case nsIEditor::eToBeginningOfLine:
case nsIEditor::eToEndOfLine:
return true;
case nsIEditor::ePrevious:
case nsIEditor::eNext:
return aSelectionOrAutoRangeArray.IsCollapsed();
default:
return false;
}
}
/**
* Returns true if aSelection includes the point in aParentContent.
*/
static bool IsPointInSelection(const Selection& aSelection,
const nsINode& aParentNode, uint32_t aOffset);
/**
* Create an nsITransferable instance which has kUnicodeMime and
* kMozTextInternal flavors.
*/
static Result<nsCOMPtr<nsITransferable>, nsresult>
CreateTransferableForPlainText(const dom::Document& aDocument);
};
} // namespace mozilla
#endif // #ifndef mozilla_EditorUtils_h