/* -*- 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 "DeleteNodeTransaction.h"

#include "mozilla/EditorBase.h"

#include "mozilla/SelectionState.h" // RangeUpdater

#include "nsDebug.h"

#include "nsError.h"

#include "nsAString.h"

namespace mozilla {

// static

already_AddRefed<DeleteNodeTransaction>

DeleteNodeTransaction::MaybeCreate(EditorBase& aEditorBase,

                              nsINode& aNodeToDelete)

{

  RefPtr<DeleteNodeTransaction> transaction =

    new DeleteNodeTransaction(aEditorBase, aNodeToDelete);

  if (NS_WARN_IF(!transaction->CanDoIt())) {

    return nullptr;

  }

  return transaction.forget();

}

DeleteNodeTransaction::DeleteNodeTransaction(EditorBase& aEditorBase,

                                             nsINode& aNodeToDelete)

  : mEditorBase(&aEditorBase)

  , mNodeToDelete(&aNodeToDelete)

  , mParentNode(aNodeToDelete.GetParentNode())

{

}

DeleteNodeTransaction::~DeleteNodeTransaction()

{

}

NS_IMPL_CYCLE_COLLECTION_INHERITED(DeleteNodeTransaction, EditTransactionBase,

                                   mEditorBase,

                                   mNodeToDelete,

                                   mParentNode,

                                   mRefNode)

NS_IMPL_ADDREF_INHERITED(DeleteNodeTransaction, EditTransactionBase)

NS_IMPL_RELEASE_INHERITED(DeleteNodeTransaction, EditTransactionBase)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(DeleteNodeTransaction)

NS_INTERFACE_MAP_END_INHERITING(EditTransactionBase)

bool

DeleteNodeTransaction::CanDoIt() const

{

  if (NS_WARN_IF(!mNodeToDelete) || NS_WARN_IF(!mEditorBase) ||

      !mParentNode || !mEditorBase->IsModifiableNode(*mParentNode)) {

    return false;

  }

  return true;

}

NS_IMETHODIMP

DeleteNodeTransaction::DoTransaction()

{

  if (NS_WARN_IF(!CanDoIt())) {

    return NS_OK;

  }

  // Remember which child mNodeToDelete was (by remembering which child was

  // next).  Note that mRefNode can be nullptr.

  mRefNode = mNodeToDelete->GetNextSibling();

  // give range updater a chance.  SelAdjDeleteNode() needs to be called

  // *before* we do the action, unlike some of the other RangeItem update

  // methods.

  mEditorBase->RangeUpdaterRef().SelAdjDeleteNode(mNodeToDelete);

  ErrorResult error;

  mParentNode->RemoveChild(*mNodeToDelete, error);

  return error.StealNSResult();

}

NS_IMETHODIMP

DeleteNodeTransaction::UndoTransaction()

{

  if (NS_WARN_IF(!CanDoIt())) {

    // This is a legal state, the transaction is a no-op.

    return NS_OK;

  }

  ErrorResult error;

  nsCOMPtr<nsIContent> refNode = mRefNode;

  mParentNode->InsertBefore(*mNodeToDelete, refNode, error);

  return error.StealNSResult();

}

NS_IMETHODIMP

DeleteNodeTransaction::RedoTransaction()

{

  if (NS_WARN_IF(!CanDoIt())) {

    // This is a legal state, the transaction is a no-op.

    return NS_OK;

  }

  mEditorBase->RangeUpdaterRef().SelAdjDeleteNode(mNodeToDelete);

  ErrorResult error;

  mParentNode->RemoveChild(*mNodeToDelete, error);

  return error.StealNSResult();

}

} // namespace mozilla