michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include <stdio.h>                      // for printf
michael@0: 
michael@0: #include "JoinElementTxn.h"
michael@0: #include "nsAString.h"
michael@0: #include "nsDebug.h"                    // for NS_ASSERTION, etc
michael@0: #include "nsEditor.h"                   // for nsEditor
michael@0: #include "nsError.h"                    // for NS_ERROR_NULL_POINTER, etc
michael@0: #include "nsIDOMCharacterData.h"        // for nsIDOMCharacterData
michael@0: #include "nsIEditor.h"                  // for nsEditor::IsModifiableNode
michael@0: #include "nsINode.h"                    // for nsINode
michael@0: #include "nsISupportsImpl.h"            // for EditTxn::QueryInterface, etc
michael@0: 
michael@0: JoinElementTxn::JoinElementTxn()
michael@0:   : EditTxn()
michael@0: {
michael@0: }
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_INHERITED(JoinElementTxn, EditTxn,
michael@0:                                    mLeftNode,
michael@0:                                    mRightNode,
michael@0:                                    mParent)
michael@0: 
michael@0: NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(JoinElementTxn)
michael@0: NS_INTERFACE_MAP_END_INHERITING(EditTxn)
michael@0: 
michael@0: NS_IMETHODIMP JoinElementTxn::Init(nsEditor   *aEditor,
michael@0:                                    nsIDOMNode *aLeftNode,
michael@0:                                    nsIDOMNode *aRightNode)
michael@0: {
michael@0:   NS_PRECONDITION((aEditor && aLeftNode && aRightNode), "null arg");
michael@0:   if (!aEditor || !aLeftNode || !aRightNode) { return NS_ERROR_NULL_POINTER; }
michael@0:   mEditor = aEditor;
michael@0:   mLeftNode = do_QueryInterface(aLeftNode);
michael@0:   nsCOMPtr<nsIDOMNode>leftParent;
michael@0:   nsresult result = mLeftNode->GetParentNode(getter_AddRefs(leftParent));
michael@0:   NS_ENSURE_SUCCESS(result, result);
michael@0:   if (!mEditor->IsModifiableNode(leftParent)) {
michael@0:     return NS_ERROR_FAILURE;
michael@0:   }
michael@0:   mRightNode = do_QueryInterface(aRightNode);
michael@0:   mOffset = 0;
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: // After DoTransaction() and RedoTransaction(), the left node is removed from the content tree and right node remains.
michael@0: NS_IMETHODIMP JoinElementTxn::DoTransaction(void)
michael@0: {
michael@0:   NS_PRECONDITION((mEditor && mLeftNode && mRightNode), "null arg");
michael@0:   if (!mEditor || !mLeftNode || !mRightNode) { return NS_ERROR_NOT_INITIALIZED; }
michael@0: 
michael@0:   // get the parent node
michael@0:   nsCOMPtr<nsIDOMNode> leftParent;
michael@0:   mLeftNode->GetParentNode(getter_AddRefs(leftParent));
michael@0:   NS_ENSURE_TRUE(leftParent, NS_ERROR_NULL_POINTER);
michael@0: 
michael@0:   // verify that mLeftNode and mRightNode have the same parent
michael@0:   nsCOMPtr<nsIDOMNode> rightParent;
michael@0:   mRightNode->GetParentNode(getter_AddRefs(rightParent));
michael@0:   NS_ENSURE_TRUE(rightParent, NS_ERROR_NULL_POINTER);
michael@0: 
michael@0:   if (leftParent != rightParent) {
michael@0:     NS_ASSERTION(false, "2 nodes do not have same parent");
michael@0:     return NS_ERROR_INVALID_ARG;
michael@0:   }
michael@0: 
michael@0:   // set this instance mParent. 
michael@0:   // Other methods will see a non-null mParent and know all is well
michael@0:   mParent = leftParent;
michael@0:   nsCOMPtr<nsINode> leftNode = do_QueryInterface(mLeftNode);
michael@0:   nsCOMPtr<nsINode> rightNode = do_QueryInterface(mRightNode);
michael@0:   nsCOMPtr<nsINode> parent = do_QueryInterface(mParent);
michael@0:   NS_ENSURE_TRUE(leftNode && rightNode && parent, NS_ERROR_FAILURE);
michael@0:   mOffset = leftNode->Length();
michael@0: 
michael@0:   return mEditor->JoinNodesImpl(rightNode, leftNode, parent);
michael@0: }
michael@0: 
michael@0: //XXX: what if instead of split, we just deleted the unneeded children of mRight
michael@0: //     and re-inserted mLeft?
michael@0: NS_IMETHODIMP JoinElementTxn::UndoTransaction(void)
michael@0: {
michael@0:   NS_ASSERTION(mRightNode && mLeftNode && mParent, "bad state");
michael@0:   if (!mRightNode || !mLeftNode || !mParent) { return NS_ERROR_NOT_INITIALIZED; }
michael@0:   nsresult result;
michael@0:   nsCOMPtr<nsIDOMNode>resultNode;
michael@0:   // first, massage the existing node so it is in its post-split state
michael@0:   nsCOMPtr<nsIDOMCharacterData>rightNodeAsText = do_QueryInterface(mRightNode);
michael@0:   if (rightNodeAsText)
michael@0:   {
michael@0:     result = rightNodeAsText->DeleteData(0, mOffset);
michael@0:   }
michael@0:   else
michael@0:   {
michael@0:     nsCOMPtr<nsIDOMNode>child;
michael@0:     result = mRightNode->GetFirstChild(getter_AddRefs(child));
michael@0:     nsCOMPtr<nsIDOMNode>nextSibling;
michael@0:     uint32_t i;
michael@0:     for (i=0; i<mOffset; i++)
michael@0:     {
michael@0:       if (NS_FAILED(result)) {return result;}
michael@0:       if (!child) {return NS_ERROR_NULL_POINTER;}
michael@0:       child->GetNextSibling(getter_AddRefs(nextSibling));
michael@0:       result = mLeftNode->AppendChild(child, getter_AddRefs(resultNode));
michael@0:       child = do_QueryInterface(nextSibling);
michael@0:     }
michael@0:   }
michael@0:   // second, re-insert the left node into the tree 
michael@0:   result = mParent->InsertBefore(mLeftNode, mRightNode, getter_AddRefs(resultNode));
michael@0:   return result;
michael@0: 
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP JoinElementTxn::GetTxnDescription(nsAString& aString)
michael@0: {
michael@0:   aString.AssignLiteral("JoinElementTxn");
michael@0:   return NS_OK;
michael@0: }