gecko-dev/editor/base/JoinElementTxn.cpp

182 lines
5.4 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 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#include "JoinElementTxn.h"
#include "nsEditor.h"
#include "nsIDOMNodeList.h"
#include "nsIDOMCharacterData.h"
#include "nsIDOMSelection.h"
#ifdef NS_DEBUG
static PRBool gNoisy = PR_FALSE;
#else
static const PRBool gNoisy = PR_FALSE;
#endif
JoinElementTxn::JoinElementTxn()
: EditTxn()
{
}
NS_IMETHODIMP JoinElementTxn::Init(nsIEditor *aEditor,
nsIDOMNode *aLeftNode,
nsIDOMNode *aRightNode)
{
mEditor = aEditor;
mLeftNode = do_QueryInterface(aLeftNode);
mRightNode = do_QueryInterface(aRightNode);
mOffset=0;
return NS_OK;
}
JoinElementTxn::~JoinElementTxn()
{
}
// After Do() and Redo(), the left node is removed from the content tree and right node remains.
NS_IMETHODIMP JoinElementTxn::Do(void)
{
if (gNoisy) { printf("%p Do Join of %p and %p\n", this, mLeftNode.get(), mRightNode.get()); }
nsresult result;
if ((mLeftNode) && (mRightNode))
{ // get the parent node
nsCOMPtr<nsIDOMNode>leftParent;
result = mLeftNode->GetParentNode(getter_AddRefs(leftParent));
if ((NS_SUCCEEDED(result)) && (leftParent))
{ // verify that mLeftNode and mRightNode have the same parent
nsCOMPtr<nsIDOMNode>rightParent;
result = mRightNode->GetParentNode(getter_AddRefs(rightParent));
if ((NS_SUCCEEDED(result)) && (rightParent))
{
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<nsIDOMNodeList> childNodes;
result = mLeftNode->GetChildNodes(getter_AddRefs(childNodes));
if ((NS_SUCCEEDED(result)) && (childNodes)) {
childNodes->GetLength(&mOffset);
}
else
{
nsCOMPtr<nsIDOMCharacterData> leftNodeAsText;
leftNodeAsText = do_QueryInterface(mLeftNode);
if (leftNodeAsText) {
leftNodeAsText->GetLength(&mOffset);
}
}
result = nsEditor::JoinNodesImpl(mRightNode, mLeftNode, mParent, PR_FALSE);
if (NS_SUCCEEDED(result))
{
if (gNoisy) { printf(" left node = %p removed\n", mLeftNode.get()); }
nsCOMPtr<nsIDOMSelection>selection;
mEditor->GetSelection(getter_AddRefs(selection));
if (selection)
{
selection->Collapse(mRightNode, mOffset);
}
}
}
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::Undo(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(PRBool *aDidMerge, nsITransaction *aTransaction)
{
if (nsnull!=aDidMerge)
*aDidMerge=PR_FALSE;
return NS_OK;
}
NS_IMETHODIMP JoinElementTxn::Write(nsIOutputStream *aOutputStream)
{
return NS_OK;
}
NS_IMETHODIMP JoinElementTxn::GetUndoString(nsString *aString)
{
if (nsnull!=aString)
{
*aString="Join Element";
}
return NS_OK;
}
NS_IMETHODIMP JoinElementTxn::GetRedoString(nsString *aString)
{
if (nsnull!=aString)
{
*aString="Split Element";
}
return NS_OK;
}