/* -*- 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.
 */

#ifndef CreateElementTxn_h__
#define CreateElementTxn_h__

#include "EditTxn.h"
#include "nsIEditor.h"
#include "nsIDOMNode.h"
#include "nsCOMPtr.h"

#define CREATE_ELEMENT_TXN_IID \
{/* 7a6393c0-ac48-11d2-86d8-000064657374 */ \
0x7a6393c0, 0xac48, 0x11d2, \
{0x86, 0xd8, 0x0, 0x0, 0x64, 0x65, 0x73, 0x74} }

/**
 * A transaction that creates a new node in the content tree.
 */
class CreateElementTxn : public EditTxn
{
public:

  enum { eAppend=-1 };

  /** Initialize the transaction.
    * @param aEditor the provider of basic editing functionality
    * @param aTag    the tag (P, HR, TABLE, etc.) for the new element
    * @param aParent the node into which the new element will be inserted
    * @param aOffsetInParent the location in aParent to insert the new element
    *                        if eAppend, the new element is appended as the last child
    */
  NS_IMETHOD Init(nsIEditor *aEditor,
                  const nsString& aTag,
                  nsIDOMNode *aParent,
                  PRUint32 aOffsetInParent);

private:
  CreateElementTxn();

public:

  virtual ~CreateElementTxn();

  NS_IMETHOD Do(void);

  NS_IMETHOD Undo(void);

  NS_IMETHOD Redo(void);

  NS_IMETHOD Merge(PRBool *aDidMerge, nsITransaction *aTransaction);

  NS_IMETHOD Write(nsIOutputStream *aOutputStream);

  NS_IMETHOD GetUndoString(nsString **aString);

  NS_IMETHOD GetRedoString(nsString **aString);

  NS_IMETHOD GetNewNode(nsIDOMNode **aNewNode);

protected:
  
  /** the document into which the new node will be inserted */
  nsCOMPtr<nsIEditor> mEditor;
  
  /** the tag (mapping to object type) for the new element */
  nsString mTag;

  /** the node into which the new node will be inserted */
  nsCOMPtr<nsIDOMNode> mParent;

  /** the index in mParent for the new node */
  PRUint32 mOffsetInParent;

  /** the new node to insert */
  nsCOMPtr<nsIDOMNode> mNewNode;  

  /** the node we will insert mNewNode before.  We compute this ourselves. */
  nsCOMPtr<nsIDOMNode> mRefNode;

  friend class TransactionFactory;

};

#endif