gecko/editor/libeditor/base/JoinElementTxn.cpp

204 lines
6.9 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
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*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998-1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
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#include "JoinElementTxn.h"
#include "nsEditor.h"
#include "nsIDOMNodeList.h"
#include "nsIDOMCharacterData.h"
#ifdef NS_DEBUG
static PRBool gNoisy = PR_FALSE;
#endif
JoinElementTxn::JoinElementTxn()
: EditTxn()
{
}
NS_IMPL_CYCLE_COLLECTION_CLASS(JoinElementTxn)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(JoinElementTxn, EditTxn)
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mLeftNode)
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mRightNode)
NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mParent)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(JoinElementTxn, EditTxn)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR(mLeftNode)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR(mRightNode)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR(mParent)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(JoinElementTxn)
NS_INTERFACE_MAP_END_INHERITING(EditTxn)
NS_IMETHODIMP JoinElementTxn::Init(nsEditor *aEditor,
nsIDOMNode *aLeftNode,
nsIDOMNode *aRightNode)
{
NS_PRECONDITION((aEditor && aLeftNode && aRightNode), "null arg");
if (!aEditor || !aLeftNode || !aRightNode) { return NS_ERROR_NULL_POINTER; }
mEditor = aEditor;
mLeftNode = do_QueryInterface(aLeftNode);
nsCOMPtr<nsIDOMNode>leftParent;
nsresult result = mLeftNode->GetParentNode(getter_AddRefs(leftParent));
if (NS_FAILED(result)) return result;
if (!mEditor->IsModifiableNode(leftParent)) {
return NS_ERROR_FAILURE;
}
mRightNode = do_QueryInterface(aRightNode);
mOffset=0;
return NS_OK;
}
// After DoTransaction() and RedoTransaction(), the left node is removed from the content tree and right node remains.
NS_IMETHODIMP JoinElementTxn::DoTransaction(void)
{
#ifdef NS_DEBUG
if (gNoisy)
{
printf("%p Do Join of %p and %p\n",
static_cast<void*>(this),
static_cast<void*>(mLeftNode.get()),
static_cast<void*>(mRightNode.get()));
}
#endif
NS_PRECONDITION((mEditor && mLeftNode && mRightNode), "null arg");
if (!mEditor || !mLeftNode || !mRightNode) { return NS_ERROR_NOT_INITIALIZED; }
// get the parent node
nsCOMPtr<nsIDOMNode>leftParent;
nsresult result = mLeftNode->GetParentNode(getter_AddRefs(leftParent));
if (NS_FAILED(result)) return result;
if (!leftParent) return NS_ERROR_NULL_POINTER;
// verify that mLeftNode and mRightNode have the same parent
nsCOMPtr<nsIDOMNode>rightParent;
result = mRightNode->GetParentNode(getter_AddRefs(rightParent));
if (NS_FAILED(result)) return result;
if (!rightParent) return NS_ERROR_NULL_POINTER;
if (leftParent==rightParent)
{
mParent= do_QueryInterface(leftParent); // set this instance mParent.
// Other methods will see a non-null mParent and know all is well
nsCOMPtr<nsIDOMCharacterData> leftNodeAsText = do_QueryInterface(mLeftNode);
if (leftNodeAsText)
{
leftNodeAsText->GetLength(&mOffset);
}
else
{
nsCOMPtr<nsIDOMNodeList> childNodes;
result = mLeftNode->GetChildNodes(getter_AddRefs(childNodes));
if (NS_FAILED(result)) return result;
if (childNodes)
{
childNodes->GetLength(&mOffset);
}
}
result = mEditor->JoinNodesImpl(mRightNode, mLeftNode, mParent, PR_FALSE);
#ifdef NS_DEBUG
if (NS_SUCCEEDED(result))
{
if (gNoisy)
{
printf(" left node = %p removed\n",
static_cast<void*>(mLeftNode.get()));
}
}
#endif
}
else
{
NS_ASSERTION(PR_FALSE, "2 nodes do not have same parent");
return NS_ERROR_INVALID_ARG;
}
return result;
}
//XXX: what if instead of split, we just deleted the unneeded children of mRight
// and re-inserted mLeft?
NS_IMETHODIMP JoinElementTxn::UndoTransaction(void)
{
#ifdef NS_DEBUG
if (gNoisy)
{
printf("%p Undo Join, right node = %p\n",
static_cast<void*>(this),
static_cast<void*>(mRightNode.get()));
}
#endif
NS_ASSERTION(mRightNode && mLeftNode && mParent, "bad state");
if (!mRightNode || !mLeftNode || !mParent) { return NS_ERROR_NOT_INITIALIZED; }
nsresult result;
nsCOMPtr<nsIDOMNode>resultNode;
// first, massage the existing node so it is in its post-split state
nsCOMPtr<nsIDOMCharacterData>rightNodeAsText = do_QueryInterface(mRightNode);
if (rightNodeAsText)
{
result = rightNodeAsText->DeleteData(0, mOffset);
}
else
{
nsCOMPtr<nsIDOMNode>child;
result = mRightNode->GetFirstChild(getter_AddRefs(child));
nsCOMPtr<nsIDOMNode>nextSibling;
PRUint32 i;
for (i=0; i<mOffset; i++)
{
if (NS_FAILED(result)) {return result;}
if (!child) {return NS_ERROR_NULL_POINTER;}
child->GetNextSibling(getter_AddRefs(nextSibling));
result = mLeftNode->AppendChild(child, getter_AddRefs(resultNode));
child = do_QueryInterface(nextSibling);
}
}
// second, re-insert the left node into the tree
result = mParent->InsertBefore(mLeftNode, mRightNode, getter_AddRefs(resultNode));
return result;
}
NS_IMETHODIMP JoinElementTxn::GetTxnDescription(nsAString& aString)
{
aString.AssignLiteral("JoinElementTxn");
return NS_OK;
}