/* -*- 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 "InsertElementTxn.h"
#include "nsIDOMSelection.h"
#include "nsIContent.h"

#ifdef NS_DEBUG
static PRBool gNoisy = PR_FALSE;
#else
static const PRBool gNoisy = PR_FALSE;
#endif


InsertElementTxn::InsertElementTxn()
  : EditTxn()
{
}

NS_IMETHODIMP InsertElementTxn::Init(nsIDOMNode *aNode,
                                     nsIDOMNode *aParent,
                                     PRInt32     aOffset,
                                     nsIEditor  *aEditor)
{
  NS_ASSERTION(aNode && aParent && aEditor, "bad arg");
  if (!aNode || !aParent || !aEditor)
    return NS_ERROR_NULL_POINTER;

  mNode = do_QueryInterface(aNode);
  mParent = do_QueryInterface(aParent);
  mOffset = aOffset;
  mEditor = aEditor;
  if (!mNode || !mParent || !mEditor)
    return NS_ERROR_INVALID_ARG;
  return NS_OK;
}


InsertElementTxn::~InsertElementTxn()
{
}

NS_IMETHODIMP InsertElementTxn::Do(void)
{
  if (gNoisy) 
  { 
    nsCOMPtr<nsIContent>nodeAsContent = do_QueryInterface(mNode);
    nsCOMPtr<nsIContent>parentAsContent = do_QueryInterface(mParent);
    printf("%p Do Insert Element of %p into parent %p at offset %d\n", 
                       this, nodeAsContent.get(), parentAsContent.get(), mOffset); 
  }
  if (!mNode || !mParent)
    return NS_ERROR_NULL_POINTER;

  nsresult result;
  nsCOMPtr<nsIDOMNode>refNode;
  //if (0!=mOffset)
  { // get a ref node
    PRInt32 i=0;
    result = mParent->GetFirstChild(getter_AddRefs(refNode));
    if (NS_SUCCEEDED(result) && refNode)
    {
      for (; i<mOffset; i++)
      {
        nsCOMPtr<nsIDOMNode>nextSib;
        result = refNode->GetNextSibling(getter_AddRefs(nextSib));  
        if (NS_FAILED(result)) {
          break;  // couldn't get a next sibling, so make aNode the first child
        }
        refNode = do_QueryInterface(nextSib);
        if (!refNode) {
          break;  // couldn't get a next sibling, so make aNode the first child
        }
      }
    }
  }

  nsCOMPtr<nsIDOMNode> resultNode;
  result = mParent->InsertBefore(mNode, refNode, getter_AddRefs(resultNode));
  if (NS_SUCCEEDED(result) && resultNode)
  {
    nsCOMPtr<nsIDOMSelection> selection;
    result = mEditor->GetSelection(getter_AddRefs(selection));
    if ((NS_SUCCEEDED(result)) && selection)
    { // place the selection just after the inserted element
      selection->Collapse(mParent, mOffset+1);
      //selection->Extend(mParent, mOffset+1);
    }    
  }
  return result;
}

NS_IMETHODIMP InsertElementTxn::Undo(void)
{
  if (gNoisy) { printf("%p Undo Insert Element of %p into parent %p at offset %d\n", 
                       this, mNode.get(), mParent.get(), mOffset); }
  if (!mNode || !mParent)
    return NS_ERROR_NULL_POINTER;

  nsCOMPtr<nsIDOMNode> resultNode;
  nsresult result = mParent->RemoveChild(mNode, getter_AddRefs(resultNode));
  return result;
}

NS_IMETHODIMP InsertElementTxn::Merge(PRBool *aDidMerge, nsITransaction *aTransaction)
{
  if (nsnull!=aDidMerge)
    *aDidMerge=PR_FALSE;
  return NS_OK;
}

NS_IMETHODIMP InsertElementTxn::Write(nsIOutputStream *aOutputStream)
{
  return NS_OK;
}

NS_IMETHODIMP InsertElementTxn::GetUndoString(nsString *aString)
{
  if (nsnull!=aString)
  {
    *aString="Remove Element: ";
  }
  return NS_OK;
}

NS_IMETHODIMP InsertElementTxn::GetRedoString(nsString *aString)
{
  if (nsnull!=aString)
  {
    *aString="Insert Element: ";
  }
  return NS_OK;
}