custom-app/dhcc-app-dll/node_modules/draft-js/lib/getContentStateFragment.js.flow

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/**
 * Copyright (c) 2013-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 *
 * @providesModule getContentStateFragment
 * @format
 * @flow
 */

'use strict';

import type { BlockMap } from './BlockMap';
import type ContentState from './ContentState';
import type SelectionState from './SelectionState';

const randomizeBlockMapKeys = require('./randomizeBlockMapKeys');
const removeEntitiesAtEdges = require('./removeEntitiesAtEdges');

const getContentStateFragment = (contentState: ContentState, selectionState: SelectionState): BlockMap => {
  const startKey = selectionState.getStartKey();
  const startOffset = selectionState.getStartOffset();
  const endKey = selectionState.getEndKey();
  const endOffset = selectionState.getEndOffset();

  // Edge entities should be stripped to ensure that we don't preserve
  // invalid partial entities when the fragment is reused. We do, however,
  // preserve entities that are entirely within the selection range.
  const contentWithoutEdgeEntities = removeEntitiesAtEdges(contentState, selectionState);

  const blockMap = contentWithoutEdgeEntities.getBlockMap();
  const blockKeys = blockMap.keySeq();
  const startIndex = blockKeys.indexOf(startKey);
  const endIndex = blockKeys.indexOf(endKey) + 1;

  return randomizeBlockMapKeys(blockMap.slice(startIndex, endIndex).map((block, blockKey) => {
    const text = block.getText();
    const chars = block.getCharacterList();

    if (startKey === endKey) {
      return block.merge({
        text: text.slice(startOffset, endOffset),
        characterList: chars.slice(startOffset, endOffset)
      });
    }

    if (blockKey === startKey) {
      return block.merge({
        text: text.slice(startOffset),
        characterList: chars.slice(startOffset)
      });
    }

    if (blockKey === endKey) {
      return block.merge({
        text: text.slice(0, endOffset),
        characterList: chars.slice(0, endOffset)
      });
    }

    return block;
  }));
};

module.exports = getContentStateFragment;