gecko-dev/editor/libeditor/base/SplitElementTxn.cpp

256 lines
8.0 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 <stdio.h> // for printf
#include "SplitElementTxn.h"
#include "nsAString.h"
#include "nsDebug.h" // for NS_ASSERTION, etc
#include "nsEditor.h" // for nsEditor
#include "nsError.h" // for NS_ERROR_NOT_INITIALIZED, etc
#include "nsIContent.h" // for nsIContent
#include "nsIDOMCharacterData.h" // for nsIDOMCharacterData
#include "nsIEditor.h" // for nsEditor::DebugDumpContent, etc
#include "nsISelection.h" // for nsISelection
#include "nsISupportsUtils.h" // for NS_ADDREF
using namespace mozilla;
#ifdef DEBUG
static bool gNoisy = false;
#endif
// note that aEditor is not refcounted
SplitElementTxn::SplitElementTxn()
: EditTxn()
{
}
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(SplitElementTxn, EditTxn)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mParent)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mNewLeftNode)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(SplitElementTxn, EditTxn)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParent)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mNewLeftNode)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_ADDREF_INHERITED(SplitElementTxn, EditTxn)
NS_IMPL_RELEASE_INHERITED(SplitElementTxn, EditTxn)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(SplitElementTxn)
NS_INTERFACE_MAP_END_INHERITING(EditTxn)
NS_IMETHODIMP SplitElementTxn::Init(nsEditor *aEditor,
nsINode *aNode,
int32_t aOffset)
{
NS_ASSERTION(aEditor && aNode, "bad args");
if (!aEditor || !aNode) { return NS_ERROR_NOT_INITIALIZED; }
mEditor = aEditor;
mExistingRightNode = do_QueryInterface(aNode);
mOffset = aOffset;
return NS_OK;
}
NS_IMETHODIMP SplitElementTxn::DoTransaction(void)
{
#ifdef DEBUG
if (gNoisy)
{
printf("%p Do Split of node %p offset %d\n",
static_cast<void*>(this),
static_cast<void*>(mExistingRightNode.get()),
mOffset);
}
#endif
NS_ASSERTION(mExistingRightNode && mEditor, "bad state");
if (!mExistingRightNode || !mEditor) { return NS_ERROR_NOT_INITIALIZED; }
// create a new node
ErrorResult rv;
mNewLeftNode = mExistingRightNode->CloneNode(false, rv);
NS_ENSURE_SUCCESS(rv.ErrorCode(), rv.ErrorCode());
NS_ASSERTION(mNewLeftNode, "could not create element.");
NS_ENSURE_TRUE(mNewLeftNode, NS_ERROR_NULL_POINTER);
mEditor->MarkNodeDirty(mExistingRightNode);
#ifdef DEBUG
if (gNoisy)
{
printf(" created left node = %p\n",
static_cast<void*>(mNewLeftNode.get()));
}
#endif
// get the parent node
mParent = mExistingRightNode->GetParentNode();
NS_ENSURE_TRUE(mParent, NS_ERROR_NULL_POINTER);
// insert the new node
nsresult result = mEditor->SplitNodeImpl(mExistingRightNode->AsDOMNode(),
mOffset,
mNewLeftNode->AsDOMNode(),
mParent->AsDOMNode());
NS_ENSURE_SUCCESS(result, result);
if (mNewLeftNode) {
bool bAdjustSelection;
mEditor->ShouldTxnSetSelection(&bAdjustSelection);
if (bAdjustSelection)
{
nsCOMPtr<nsISelection> selection;
result = mEditor->GetSelection(getter_AddRefs(selection));
NS_ENSURE_SUCCESS(result, result);
NS_ENSURE_TRUE(selection, NS_ERROR_NULL_POINTER);
result = selection->Collapse(mNewLeftNode->AsDOMNode(), mOffset);
}
else
{
// do nothing - dom range gravity will adjust selection
}
}
return result;
}
NS_IMETHODIMP SplitElementTxn::UndoTransaction(void)
{
#ifdef DEBUG
if (gNoisy) {
printf("%p Undo Split of existing node %p and new node %p offset %d\n",
static_cast<void*>(this),
static_cast<void*>(mExistingRightNode.get()),
static_cast<void*>(mNewLeftNode.get()),
mOffset);
}
#endif
NS_ASSERTION(mEditor && mExistingRightNode && mNewLeftNode && mParent, "bad state");
if (!mEditor || !mExistingRightNode || !mNewLeftNode || !mParent) {
return NS_ERROR_NOT_INITIALIZED;
}
// this assumes Do inserted the new node in front of the prior existing node
nsresult result = mEditor->JoinNodesImpl(mExistingRightNode->AsDOMNode(),
mNewLeftNode->AsDOMNode(),
mParent->AsDOMNode(),
false);
#ifdef DEBUG
if (gNoisy)
{
printf("** after join left child node %p into right node %p\n",
static_cast<void*>(mNewLeftNode.get()),
static_cast<void*>(mExistingRightNode.get()));
if (gNoisy) {mEditor->DebugDumpContent(); } // DEBUG
}
if (NS_SUCCEEDED(result))
{
if (gNoisy)
{
printf(" left node = %p removed\n",
static_cast<void*>(mNewLeftNode.get()));
}
}
#endif
return result;
}
/* redo cannot simply resplit the right node, because subsequent transactions
* on the redo stack may depend on the left node existing in its previous state.
*/
NS_IMETHODIMP SplitElementTxn::RedoTransaction(void)
{
NS_ASSERTION(mEditor && mExistingRightNode && mNewLeftNode && mParent, "bad state");
if (!mEditor || !mExistingRightNode || !mNewLeftNode || !mParent) {
return NS_ERROR_NOT_INITIALIZED;
}
#ifdef DEBUG
if (gNoisy) {
printf("%p Redo Split of existing node %p and new node %p offset %d\n",
static_cast<void*>(this),
static_cast<void*>(mExistingRightNode.get()),
static_cast<void*>(mNewLeftNode.get()),
mOffset);
if (gNoisy) {mEditor->DebugDumpContent(); } // DEBUG
}
#endif
// first, massage the existing node so it is in its post-split state
nsCOMPtr<nsIDOMCharacterData>rightNodeAsText = do_QueryInterface(mExistingRightNode);
if (rightNodeAsText)
{
nsresult result = rightNodeAsText->DeleteData(0, mOffset);
NS_ENSURE_SUCCESS(result, result);
#ifdef DEBUG
if (gNoisy)
{
printf("** after delete of text in right text node %p offset %d\n",
static_cast<void*>(rightNodeAsText.get()),
mOffset);
mEditor->DebugDumpContent(); // DEBUG
}
#endif
}
else
{
nsCOMPtr<nsINode> child = mExistingRightNode->GetFirstChild();
for (int32_t i=0; i<mOffset; i++)
{
if (!child) {return NS_ERROR_NULL_POINTER;}
ErrorResult rv;
mExistingRightNode->RemoveChild(*child, rv);
if (NS_SUCCEEDED(rv.ErrorCode()))
{
mNewLeftNode->AppendChild(*child, rv);
NS_ENSURE_SUCCESS(rv.ErrorCode(), rv.ErrorCode());
#ifdef DEBUG
if (gNoisy)
{
printf("** move child node %p from right node %p to left node %p\n",
static_cast<void*>(child),
static_cast<void*>(mExistingRightNode.get()),
static_cast<void*>(mNewLeftNode.get()));
if (gNoisy) {mEditor->DebugDumpContent(); } // DEBUG
}
#endif
}
child = child->GetNextSibling();
}
}
// second, re-insert the left node into the tree
ErrorResult rv;
mParent->InsertBefore(*mNewLeftNode, mExistingRightNode, rv);
#ifdef DEBUG
if (gNoisy)
{
printf("** reinsert left child node %p before right node %p\n",
static_cast<void*>(mNewLeftNode.get()),
static_cast<void*>(mExistingRightNode.get()));
if (gNoisy) {mEditor->DebugDumpContent(); } // DEBUG
}
#endif
return rv.ErrorCode();
}
NS_IMETHODIMP SplitElementTxn::GetTxnDescription(nsAString& aString)
{
aString.AssignLiteral("SplitElementTxn");
return NS_OK;
}
NS_IMETHODIMP SplitElementTxn::GetNewNode(nsINode **aNewNode)
{
NS_ENSURE_TRUE(aNewNode, NS_ERROR_NULL_POINTER);
NS_ENSURE_TRUE(mNewLeftNode, NS_ERROR_NOT_INITIALIZED);
*aNewNode = mNewLeftNode;
NS_ADDREF(*aNewNode);
return NS_OK;
}