gecko-dev/editor/base/JoinElementTxn.cpp

165 строки
5.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape 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 http://www.mozilla.org/NPL/
*
* 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 Netscape are
* Copyright (C) 1998-1999 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
*/
#include "JoinElementTxn.h"
#include "nsEditor.h"
#include "nsIDOMNodeList.h"
#include "nsIDOMCharacterData.h"
#ifdef NS_DEBUG
static PRBool gNoisy = PR_FALSE;
#else
static const PRBool gNoisy = PR_FALSE;
#endif
JoinElementTxn::JoinElementTxn()
: 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);
mRightNode = do_QueryInterface(aRightNode);
mOffset=0;
return NS_OK;
}
JoinElementTxn::~JoinElementTxn()
{
}
// After DoTransaction() and RedoTransaction(), the left node is removed from the content tree and right node remains.
NS_IMETHODIMP JoinElementTxn::DoTransaction(void)
{
if (gNoisy) { printf("%p Do Join of %p and %p\n", this, mLeftNode.get(), mRightNode.get()); }
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;
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);
if (NS_SUCCEEDED(result))
{
if (gNoisy) { printf(" left node = %p removed\n", mLeftNode.get()); }
}
}
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)
{
if (gNoisy) { printf("%p Undo Join, right node = %p\n", this, mRightNode.get()); }
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;
rightNodeAsText = do_QueryInterface(mRightNode);
if (rightNodeAsText)
{
result = rightNodeAsText->DeleteData(0, mOffset);
}
else
{
nsCOMPtr<nsIDOMNode>child;
nsCOMPtr<nsIDOMNode>nextSibling;
result = mRightNode->GetFirstChild(getter_AddRefs(child));
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::GetIsTransient(PRBool *aIsTransient)
{
if (nsnull!=aIsTransient)
*aIsTransient = PR_FALSE;
return NS_OK;
}
nsresult JoinElementTxn::Merge(nsITransaction *aTransaction, PRBool *aDidMerge)
{
if (nsnull!=aDidMerge)
*aDidMerge=PR_FALSE;
return NS_OK;
}
NS_IMETHODIMP JoinElementTxn::GetTxnDescription(nsAWritableString& aString)
{
aString.Assign(NS_LITERAL_STRING("JoinElementTxn"));
return NS_OK;
}