gecko-dev/editor/libeditor/base/DeleteRangeTxn.cpp
buster%netscape.com d5932338f7 added PlaceholderTxn. This is an aggregate transaction that sits on the undo stack
and merges in subsequent transactions indiscriminately until it's told to stop.
It also gives the last transaction in its child list a chance to merge the
next transaction.
All this is in support of complex transactions that result in text insertion
being able to collapse into a single undoable event.
Also improved tracking of bogus content node used when document is empty.
1999-03-15 00:57:32 +00:00

364 lines
10 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 "DeleteRangeTxn.h"
#include "nsIDOMRange.h"
#include "nsIDOMCharacterData.h"
#include "nsIDOMNodeList.h"
#include "nsIDOMSelection.h"
#include "DeleteTextTxn.h"
#include "DeleteElementTxn.h"
#include "TransactionFactory.h"
#include "nsIContentIterator.h"
#include "nsIContent.h"
#include "nsLayoutCID.h"
#ifdef NS_DEBUG
#include "nsIDOMElement.h"
#endif
static NS_DEFINE_IID(kDeleteTextTxnIID, DELETE_TEXT_TXN_IID);
static NS_DEFINE_IID(kDeleteElementTxnIID, DELETE_ELEMENT_TXN_IID);
#ifdef NS_DEBUG
static PRBool gNoisy = PR_FALSE;
#else
static const PRBool gNoisy = PR_FALSE;
#endif
// note that aEditor is not refcounted
DeleteRangeTxn::DeleteRangeTxn()
: EditAggregateTxn()
{
}
NS_IMETHODIMP DeleteRangeTxn::Init(nsIEditor *aEditor, nsIDOMRange *aRange)
{
if (aEditor && aRange)
{
mEditor = do_QueryInterface(aEditor);
mRange = do_QueryInterface(aRange);
nsresult result = aRange->GetStartParent(getter_AddRefs(mStartParent));
NS_ASSERTION((NS_SUCCEEDED(result)), "GetStartParent failed.");
result = aRange->GetEndParent(getter_AddRefs(mEndParent));
NS_ASSERTION((NS_SUCCEEDED(result)), "GetEndParent failed.");
result = aRange->GetStartOffset(&mStartOffset);
NS_ASSERTION((NS_SUCCEEDED(result)), "GetStartOffset failed.");
result = aRange->GetEndOffset(&mEndOffset);
NS_ASSERTION((NS_SUCCEEDED(result)), "GetEndOffset failed.");
result = aRange->GetCommonParent(getter_AddRefs(mCommonParent));
NS_ASSERTION((NS_SUCCEEDED(result)), "GetCommonParent failed.");
#ifdef NS_DEBUG
{
PRUint32 count;
nsCOMPtr<nsIDOMCharacterData> textNode;
textNode = do_QueryInterface(mStartParent, &result);
if (textNode)
textNode->GetLength(&count);
else
{
nsCOMPtr<nsIDOMNodeList> children;
result = mStartParent->GetChildNodes(getter_AddRefs(children));
NS_ASSERTION(((NS_SUCCEEDED(result)) && children), "bad start child list");
children->GetLength(&count);
}
NS_ASSERTION(mStartOffset<=(PRInt32)count, "bad start offset");
textNode = do_QueryInterface(mEndParent, &result);
if (textNode)
textNode->GetLength(&count);
else
{
nsCOMPtr<nsIDOMNodeList> children;
result = mEndParent->GetChildNodes(getter_AddRefs(children));
NS_ASSERTION(((NS_SUCCEEDED(result)) && children), "bad end child list");
children->GetLength(&count);
}
NS_ASSERTION(mEndOffset<=(PRInt32)count, "bad end offset");
if (gNoisy)
{
printf ("DeleteRange: %d of %p to %d of %p\n",
mStartOffset, (void *)mStartParent, mEndOffset, (void *)mEndParent);
}
}
#endif
return result;
}
else
return NS_ERROR_NULL_POINTER;
}
DeleteRangeTxn::~DeleteRangeTxn()
{
}
NS_IMETHODIMP DeleteRangeTxn::Do(void)
{
if (!mStartParent || !mEndParent || !mCommonParent)
return NS_ERROR_NULL_POINTER;
nsresult result;
// build the child transactions
if (mStartParent==mEndParent)
{ // the selection begins and ends in the same node
result = CreateTxnsToDeleteBetween(mStartParent, mStartOffset, mEndOffset);
}
else
{ // the selection ends in a different node from where it started
// delete the relevant content in the start node
result = CreateTxnsToDeleteContent(mStartParent, mStartOffset, nsIEditor::eLTR);
if (NS_SUCCEEDED(result))
{
// delete the intervening nodes
result = CreateTxnsToDeleteNodesBetween();
if (NS_SUCCEEDED(result))
{
// delete the relevant content in the end node
result = CreateTxnsToDeleteContent(mEndParent, mEndOffset, nsIEditor::eRTL);
}
}
}
// if we've successfully built this aggregate transaction, then do it.
if (NS_SUCCEEDED(result)) {
result = EditAggregateTxn::Do();
}
if (NS_SUCCEEDED(result)) {
// set the resulting selection
nsCOMPtr<nsIDOMSelection> selection;
result = mEditor->GetSelection(getter_AddRefs(selection));
if (NS_SUCCEEDED(result)) {
result = selection->Collapse(mStartParent, mStartOffset);
}
}
return result;
}
NS_IMETHODIMP DeleteRangeTxn::Undo(void)
{
if (!mStartParent || !mEndParent || !mCommonParent)
return NS_ERROR_NULL_POINTER;
nsresult result = EditAggregateTxn::Undo();
if (NS_SUCCEEDED(result)) {
// set the resulting selection
nsCOMPtr<nsIDOMSelection> selection;
result = mEditor->GetSelection(getter_AddRefs(selection));
if (NS_SUCCEEDED(result)) {
selection->Collapse(mStartParent, mStartOffset);
selection->Extend(mEndParent, mEndOffset);
}
}
return result;
}
NS_IMETHODIMP DeleteRangeTxn::Redo(void)
{
if (!mStartParent || !mEndParent || !mCommonParent)
return NS_ERROR_NULL_POINTER;
nsresult result = EditAggregateTxn::Redo();
if (NS_SUCCEEDED(result)) {
// set the resulting selection
nsCOMPtr<nsIDOMSelection> selection;
result = mEditor->GetSelection(getter_AddRefs(selection));
if (NS_SUCCEEDED(result)) {
result = selection->Collapse(mStartParent, mStartOffset);
}
}
return result;
}
NS_IMETHODIMP DeleteRangeTxn::Merge(PRBool *aDidMerge, nsITransaction *aTransaction)
{
if (nsnull!=aDidMerge)
*aDidMerge=PR_FALSE;
return NS_OK;
}
NS_IMETHODIMP DeleteRangeTxn::Write(nsIOutputStream *aOutputStream)
{
return NS_OK;
}
NS_IMETHODIMP DeleteRangeTxn::GetUndoString(nsString **aString)
{
if (nsnull!=aString)
{
**aString="Insert Range: ";
}
return NS_OK;
}
NS_IMETHODIMP DeleteRangeTxn::GetRedoString(nsString **aString)
{
if (nsnull!=aString)
{
**aString="Remove Range: ";
}
return NS_OK;
}
NS_IMETHODIMP DeleteRangeTxn::CreateTxnsToDeleteBetween(nsIDOMNode *aStartParent,
PRUint32 aStartOffset,
PRUint32 aEndOffset)
{
nsresult result;
// see what kind of node we have
nsCOMPtr<nsIDOMCharacterData> textNode;
textNode = do_QueryInterface(aStartParent);
if (textNode)
{ // if the node is a text node, then delete text content
DeleteTextTxn *txn;
result = TransactionFactory::GetNewTransaction(kDeleteTextTxnIID, (EditTxn **)&txn);
if (nsnull!=txn)
{
PRInt32 numToDel;
if (aStartOffset==aEndOffset)
numToDel = 1;
else
numToDel = aEndOffset-aStartOffset;
txn->Init(mEditor, textNode, aStartOffset, numToDel);
AppendChild(txn);
}
}
else
{
PRUint32 childCount;
nsCOMPtr<nsIDOMNodeList> children;
result = aStartParent->GetChildNodes(getter_AddRefs(children));
if ((NS_SUCCEEDED(result)) && children)
{
children->GetLength(&childCount);
NS_ASSERTION(aEndOffset<=childCount, "bad aEndOffset");
PRUint32 i;
for (i=aStartOffset; i<=aEndOffset; i++)
{
nsCOMPtr<nsIDOMNode> child;
result = children->Item(i, getter_AddRefs(child));
if ((NS_SUCCEEDED(result)) && child)
{
DeleteElementTxn *txn;
result = TransactionFactory::GetNewTransaction(kDeleteElementTxnIID, (EditTxn **)&txn);
if (nsnull!=txn)
{
txn->Init(child);
AppendChild(txn);
}
else
return NS_ERROR_NULL_POINTER;
}
}
}
}
return result;
}
NS_IMETHODIMP DeleteRangeTxn::CreateTxnsToDeleteContent(nsIDOMNode *aParent,
PRUint32 aOffset,
nsIEditor::Direction aDir)
{
nsresult result;
// see what kind of node we have
nsCOMPtr<nsIDOMCharacterData> textNode;
textNode = do_QueryInterface(aParent);
if (textNode)
{ // if the node is a text node, then delete text content
PRUint32 start, numToDelete;
if (nsIEditor::eLTR==aDir)
{
start=aOffset;
textNode->GetLength(&numToDelete);
numToDelete -= aOffset;
}
else
{
start=0;
numToDelete=aOffset;
}
if (numToDelete)
{
DeleteTextTxn *txn;
result = TransactionFactory::GetNewTransaction(kDeleteTextTxnIID, (EditTxn **)&txn);
if (nsnull!=txn)
{
txn->Init(mEditor, textNode, start, numToDelete);
AppendChild(txn);
}
else
return NS_ERROR_NULL_POINTER;
}
}
return result;
}
static NS_DEFINE_IID(kSubtreeIteratorCID, NS_SUBTREEITERATOR_CID);
static NS_DEFINE_IID(kRangeCID, NS_RANGE_CID);
NS_IMETHODIMP DeleteRangeTxn::CreateTxnsToDeleteNodesBetween()
{
nsresult result;
nsCOMPtr<nsIContentIterator> iter;
result = nsComponentManager::CreateInstance(kSubtreeIteratorCID,
nsnull,
nsIContentIterator::GetIID(),
getter_AddRefs(iter));
if (!NS_SUCCEEDED(result))
return result;
result = iter->Init(mRange);
if (!NS_SUCCEEDED(result))
return result;
while (NS_COMFALSE == iter->IsDone())
{
nsCOMPtr<nsIDOMNode> node;
nsCOMPtr<nsIContent> content;
result = iter->CurrentNode(getter_AddRefs(content));
node = do_QueryInterface(content);
if ((NS_SUCCEEDED(result)) && node)
{
DeleteElementTxn *txn;
result = TransactionFactory::GetNewTransaction(kDeleteElementTxnIID, (EditTxn **)&txn);
if (nsnull!=txn)
{
txn->Init(node);
AppendChild(txn);
}
else
return NS_ERROR_NULL_POINTER;
}
iter->Next();
}
return result;
}