/* -*- 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 "mozilla/TextEditRules.h"

#include "mozilla/TextEditor.h"

#include "mozilla/dom/Selection.h"

#include "nsCOMPtr.h"

#include "nsDebug.h"

#include "nsError.h"

#include "nsFrameSelection.h"

#include "nsIContent.h"

#include "nsIEditor.h"

#include "nsIPresShell.h"

#include "nsISupportsImpl.h"

#include "nsPresContext.h"

#include "nscore.h"

namespace mozilla {

using namespace dom;

// Test for distance between caret and text that will be deleted

nsresult TextEditRules::CheckBidiLevelForDeletion(Selection* aSelection,

                                                  nsINode* aSelNode,

                                                  int32_t aSelOffset,

                                                  nsIEditor::EDirection aAction,

                                                  bool* aCancel) {

  NS_ENSURE_ARG_POINTER(aCancel);

  *aCancel = false;

  nsCOMPtr<nsIPresShell> shell = mTextEditor->GetPresShell();

  NS_ENSURE_TRUE(shell, NS_ERROR_NOT_INITIALIZED);

  nsPresContext* context = shell->GetPresContext();

  NS_ENSURE_TRUE(context, NS_ERROR_NULL_POINTER);

  if (!context->BidiEnabled()) {

    return NS_OK;

  }

  if (!aSelNode || !aSelNode->IsContent()) {

    return NS_ERROR_NULL_POINTER;

  }

  nsCOMPtr<nsIContent> content = aSelNode->AsContent();

  nsBidiLevel levelBefore;

  nsBidiLevel levelAfter;

  RefPtr<nsFrameSelection> frameSelection =

      aSelection->AsSelection()->GetFrameSelection();

  NS_ENSURE_TRUE(frameSelection, NS_ERROR_NULL_POINTER);

  nsPrevNextBidiLevels levels =

      frameSelection->GetPrevNextBidiLevels(content, aSelOffset, true);

  levelBefore = levels.mLevelBefore;

  levelAfter = levels.mLevelAfter;

  nsBidiLevel currentCaretLevel = frameSelection->GetCaretBidiLevel();

  nsBidiLevel levelOfDeletion;

  levelOfDeletion =

      (nsIEditor::eNext == aAction || nsIEditor::eNextWord == aAction)

          ? levelAfter

          : levelBefore;

  if (currentCaretLevel == levelOfDeletion) {

    return NS_OK;  // perform the deletion

  }

  if (!mDeleteBidiImmediately && levelBefore != levelAfter) {

    *aCancel = true;

  }

  // Set the bidi level of the caret to that of the

  // character that will be (or would have been) deleted

  frameSelection->SetCaretBidiLevel(levelOfDeletion);

  return NS_OK;

}

void TextEditRules::UndefineCaretBidiLevel(Selection* aSelection) {

  /**

   * After inserting text the caret Bidi level must be set to the level of the

   * inserted text.This is difficult, because we cannot know what the level is

   * until after the Bidi algorithm is applied to the whole paragraph.

   *

   * So we set the caret Bidi level to UNDEFINED here, and the caret code will

   * set it correctly later

   */

  RefPtr<nsFrameSelection> frameSelection = aSelection->GetFrameSelection();

  if (frameSelection) {

    frameSelection->UndefineCaretBidiLevel();

  }

}

}  // namespace mozilla