File: public/js/tinymce/src/core/src/main/js/delete/DeleteUtils.js

/**
 * DeleteUtils.js
 *
 * Released under LGPL License.
 * Copyright (c) 1999-2017 Ephox Corp. All rights reserved
 *
 * License: http://www.tinymce.com/license
 * Contributing: http://www.tinymce.com/contributing
 */

define(
  'tinymce.core.delete.DeleteUtils',
  [
    'ephox.katamari.api.Option',
    'ephox.katamari.api.Options',
    'ephox.sugar.api.dom.Compare',
    'ephox.sugar.api.node.Element',
    'ephox.sugar.api.search.PredicateFind',
    'tinymce.core.caret.CaretFinder',
    'tinymce.core.dom.ElementType',
    'tinymce.core.keyboard.InlineUtils'
  ],
  function (Option, Options, Compare, Element, PredicateFind, CaretFinder, ElementType, InlineUtils) {
    var isBeforeRoot = function (rootNode) {
      return function (elm) {
        return Compare.eq(rootNode, Element.fromDom(elm.dom().parentNode));
      };
    };

    var getParentBlock = function (rootNode, elm) {
      return Compare.contains(rootNode, elm) ? PredicateFind.closest(elm, function (element) {
        return ElementType.isTextBlock(element) || ElementType.isListItem(element);
      }, isBeforeRoot(rootNode)) : Option.none();
    };

    var placeCaretInEmptyBody = function (editor) {
      var body = editor.getBody();
      var node = body.firstChild && editor.dom.isBlock(body.firstChild) ? body.firstChild : body;
      editor.selection.setCursorLocation(node, 0);
    };

    var paddEmptyBody = function (editor) {
      if (editor.dom.isEmpty(editor.getBody())) {
        editor.setContent('');
        placeCaretInEmptyBody(editor);
      }
    };

    var willDeleteLastPositionInElement = function (forward, fromPos, elm) {
      return Options.liftN([
        CaretFinder.firstPositionIn(elm),
        CaretFinder.lastPositionIn(elm)
      ], function (firstPos, lastPos) {
        var normalizedFirstPos = InlineUtils.normalizePosition(true, firstPos);
        var normalizedLastPos = InlineUtils.normalizePosition(false, lastPos);
        var normalizedFromPos = InlineUtils.normalizePosition(false, fromPos);

        if (forward) {
          return CaretFinder.nextPosition(elm, normalizedFromPos).map(function (nextPos) {
            return nextPos.isEqual(normalizedLastPos) && fromPos.isEqual(normalizedFirstPos);
          }).getOr(false);
        } else {
          return CaretFinder.prevPosition(elm, normalizedFromPos).map(function (prevPos) {
            return prevPos.isEqual(normalizedFirstPos) && fromPos.isEqual(normalizedLastPos);
          }).getOr(false);
        }
      }).getOr(true);
    };

    return {
      getParentBlock: getParentBlock,
      paddEmptyBody: paddEmptyBody,
      willDeleteLastPositionInElement: willDeleteLastPositionInElement
    };
  }
);