/* -*- 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 "InsertTextTransaction.h"

#include "mozilla/EditorBase.h"         // mEditorBase

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

#include "mozilla/dom/Selection.h"      // Selection local var

#include "mozilla/dom/Text.h"           // mTextNode

#include "nsAString.h"                  // nsAString parameter

#include "nsDebug.h"                    // for NS_ASSERTION, etc.

#include "nsError.h"                    // for NS_OK, etc.

#include "nsQueryObject.h"              // for do_QueryObject

namespace mozilla {

using namespace dom;

// static

already_AddRefed<InsertTextTransaction>

InsertTextTransaction::Create(EditorBase& aEditorBase,

                              const nsAString& aStringToInsert,

                              Text& aTextNode,

                              uint32_t aOffset)

{

  RefPtr<InsertTextTransaction> transaction =

    new InsertTextTransaction(aEditorBase, aStringToInsert, aTextNode, aOffset);

  return transaction.forget();

}

InsertTextTransaction::InsertTextTransaction(EditorBase& aEditorBase,

                                             const nsAString& aStringToInsert,

                                             Text& aTextNode,

                                             uint32_t aOffset)

  : mTextNode(&aTextNode)

  , mOffset(aOffset)

  , mStringToInsert(aStringToInsert)

  , mEditorBase(&aEditorBase)

{

}

InsertTextTransaction::~InsertTextTransaction()

{

}

NS_IMPL_CYCLE_COLLECTION_INHERITED(InsertTextTransaction, EditTransactionBase,

                                   mEditorBase,

                                   mTextNode)

NS_IMPL_ADDREF_INHERITED(InsertTextTransaction, EditTransactionBase)

NS_IMPL_RELEASE_INHERITED(InsertTextTransaction, EditTransactionBase)

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(InsertTextTransaction)

  NS_INTERFACE_MAP_ENTRY_CONCRETE(InsertTextTransaction)

NS_INTERFACE_MAP_END_INHERITING(EditTransactionBase)

NS_IMETHODIMP

InsertTextTransaction::DoTransaction()

{

  if (NS_WARN_IF(!mEditorBase) || NS_WARN_IF(!mTextNode)) {

    return NS_ERROR_NOT_AVAILABLE;

  }

  ErrorResult rv;

  mTextNode->InsertData(mOffset, mStringToInsert, rv);

  if (NS_WARN_IF(rv.Failed())) {

    return rv.StealNSResult();

  }

  // Only set selection to insertion point if editor gives permission

  if (mEditorBase->AllowsTransactionsToChangeSelection()) {

    RefPtr<Selection> selection = mEditorBase->GetSelection();

    if (NS_WARN_IF(!selection)) {

      return NS_ERROR_FAILURE;

    }

    DebugOnly<nsresult> rv =

      selection->Collapse(mTextNode, mOffset + mStringToInsert.Length());

    NS_ASSERTION(NS_SUCCEEDED(rv),

                 "Selection could not be collapsed after insert");

  } else {

    // Do nothing - DOM Range gravity will adjust selection

  }

  // XXX Other transactions do not do this but its callers do.

  //     Why do this transaction do this by itself?

  mEditorBase->RangeUpdaterRef().

                 SelAdjInsertText(*mTextNode, mOffset, mStringToInsert);

  return NS_OK;

}

NS_IMETHODIMP

InsertTextTransaction::UndoTransaction()

{

  ErrorResult rv;

  mTextNode->DeleteData(mOffset, mStringToInsert.Length(), rv);

  return rv.StealNSResult();

}

NS_IMETHODIMP

InsertTextTransaction::Merge(nsITransaction* aTransaction,

                             bool* aDidMerge)

{

  if (!aTransaction || !aDidMerge) {

    return NS_OK;

  }

  // Set out param default value

  *aDidMerge = false;

  // If aTransaction is a InsertTextTransaction, and if the selection hasn't

  // changed, then absorb it.

  RefPtr<InsertTextTransaction> otherTransaction = do_QueryObject(aTransaction);

  if (otherTransaction && IsSequentialInsert(*otherTransaction)) {

    nsAutoString otherData;

    otherTransaction->GetData(otherData);

    mStringToInsert += otherData;

    *aDidMerge = true;

  }

  return NS_OK;

}

/* ============ private methods ================== */

void

InsertTextTransaction::GetData(nsString& aResult)

{

  aResult = mStringToInsert;

}

bool

InsertTextTransaction::IsSequentialInsert(

                         InsertTextTransaction& aOtherTransaction)

{

  return aOtherTransaction.mTextNode == mTextNode &&

         aOtherTransaction.mOffset == mOffset + mStringToInsert.Length();

}

} // namespace mozilla