gecko-dev/editor/libeditor/JoinNodeTransaction.cpp

124 строки
4.2 KiB
C++

/* -*- 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/. */
#include "JoinNodeTransaction.h"
#include "mozilla/EditorBase.h" // for EditorBase
#include "mozilla/dom/Text.h"
#include "nsAString.h"
#include "nsDebug.h" // for NS_ASSERTION, etc.
#include "nsError.h" // for NS_ERROR_NULL_POINTER, etc.
#include "nsIContent.h" // for nsIContent
#include "nsISupportsImpl.h" // for QueryInterface, etc.
namespace mozilla {
using namespace dom;
// static
already_AddRefed<JoinNodeTransaction> JoinNodeTransaction::MaybeCreate(
EditorBase& aEditorBase, nsINode& aLeftNode, nsINode& aRightNode) {
RefPtr<JoinNodeTransaction> transaction =
new JoinNodeTransaction(aEditorBase, aLeftNode, aRightNode);
if (NS_WARN_IF(!transaction->CanDoIt())) {
return nullptr;
}
return transaction.forget();
}
JoinNodeTransaction::JoinNodeTransaction(EditorBase& aEditorBase,
nsINode& aLeftNode,
nsINode& aRightNode)
: mEditorBase(&aEditorBase),
mLeftNode(&aLeftNode),
mRightNode(&aRightNode),
mOffset(0) {}
NS_IMPL_CYCLE_COLLECTION_INHERITED(JoinNodeTransaction, EditTransactionBase,
mEditorBase, mLeftNode, mRightNode, mParent)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(JoinNodeTransaction)
NS_INTERFACE_MAP_END_INHERITING(EditTransactionBase)
bool JoinNodeTransaction::CanDoIt() const {
if (NS_WARN_IF(!mLeftNode) || NS_WARN_IF(!mRightNode) ||
NS_WARN_IF(!mEditorBase) || !mLeftNode->GetParentNode()) {
return false;
}
return mEditorBase->IsModifiableNode(*mLeftNode->GetParentNode());
}
// After DoTransaction() and RedoTransaction(), the left node is removed from
// the content tree and right node remains.
MOZ_CAN_RUN_SCRIPT_BOUNDARY
NS_IMETHODIMP
JoinNodeTransaction::DoTransaction() {
if (NS_WARN_IF(!mEditorBase) || NS_WARN_IF(!mLeftNode) ||
NS_WARN_IF(!mRightNode)) {
return NS_ERROR_NOT_INITIALIZED;
}
// Get the parent node
nsCOMPtr<nsINode> leftParent = mLeftNode->GetParentNode();
NS_ENSURE_TRUE(leftParent, NS_ERROR_NULL_POINTER);
// Verify that mLeftNode and mRightNode have the same parent
if (leftParent != mRightNode->GetParentNode()) {
NS_ASSERTION(false, "Nodes do not have same parent");
return NS_ERROR_INVALID_ARG;
}
// Set this instance's mParent. Other methods will see a non-null mParent
// and know all is well
mParent = leftParent;
mOffset = mLeftNode->Length();
RefPtr<EditorBase> editorBase = mEditorBase;
nsCOMPtr<nsINode> leftNode = mLeftNode;
nsCOMPtr<nsINode> rightNode = mRightNode;
return editorBase->DoJoinNodes(rightNode, leftNode, MOZ_KnownLive(mParent));
}
// XXX: What if instead of split, we just deleted the unneeded children of
// mRight and re-inserted mLeft?
MOZ_CAN_RUN_SCRIPT_BOUNDARY
NS_IMETHODIMP
JoinNodeTransaction::UndoTransaction() {
if (NS_WARN_IF(!mParent) || NS_WARN_IF(!mLeftNode) ||
NS_WARN_IF(!mRightNode) || NS_WARN_IF(!mEditorBase)) {
return NS_ERROR_NOT_INITIALIZED;
}
// First, massage the existing node so it is in its post-split state
ErrorResult rv;
if (mRightNode->GetAsText()) {
RefPtr<EditorBase> editorBase = mEditorBase;
RefPtr<Text> rightNodeAsText = mRightNode->GetAsText();
editorBase->DoDeleteText(*rightNodeAsText, 0, mOffset, rv);
if (NS_WARN_IF(rv.Failed())) {
return rv.StealNSResult();
}
} else {
nsCOMPtr<nsIContent> child = mRightNode->GetFirstChild();
for (uint32_t i = 0; i < mOffset; i++) {
if (rv.Failed()) {
return rv.StealNSResult();
}
if (!child) {
return NS_ERROR_NULL_POINTER;
}
nsCOMPtr<nsIContent> nextSibling = child->GetNextSibling();
mLeftNode->AppendChild(*child, rv);
child = nextSibling;
}
}
// Second, re-insert the left node into the tree
nsCOMPtr<nsINode> refNode = mRightNode;
mParent->InsertBefore(*mLeftNode, refNode, rv);
return rv.StealNSResult();
}
} // namespace mozilla