@jonny/draft-convert/lib/blockInlineStyles.js

Extensibly serialize & deserialize Draft.js ContentState

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _invariant = require('invariant');

var _invariant2 = _interopRequireDefault(_invariant);

var _styleObjectFunction = require('./util/styleObjectFunction');

var _styleObjectFunction2 = _interopRequireDefault(_styleObjectFunction);

var _accumulateFunction = require('./util/accumulateFunction');

var _accumulateFunction2 = _interopRequireDefault(_accumulateFunction);

var _getElementHTML = require('./util/getElementHTML');

var _getElementHTML2 = _interopRequireDefault(_getElementHTML);

var _rangeSort = require('./util/rangeSort');

var _rangeSort2 = _interopRequireDefault(_rangeSort);

var _defaultInlineHTML = require('./default/defaultInlineHTML');

var _defaultInlineHTML2 = _interopRequireDefault(_defaultInlineHTML);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

var subtractStyles = function subtractStyles(original, toRemove) {
  return original.filter(function (el) {
    return !toRemove.some(function (elToRemove) {
      return elToRemove.style === el.style;
    });
  });
};

var popEndingStyles = function popEndingStyles(styleStack, endingStyles) {
  return endingStyles.reduceRight(function (stack, style) {
    var styleToRemove = stack[stack.length - 1];

    (0, _invariant2.default)(styleToRemove.style === style.style, 'Style ' + styleToRemove.style + ' to be removed doesn\'t match expected ' + style.style);

    return stack.slice(0, -1);
  }, styleStack);
};

var characterStyles = function characterStyles(offset, ranges) {
  return ranges.filter(function (range) {
    return offset >= range.offset && offset < range.offset + range.length;
  });
};

var rangeIsSubset = function rangeIsSubset(firstRange, secondRange) {
  // returns true if the second range is a subset of the first
  var secondStartWithinFirst = firstRange.offset <= secondRange.offset;
  var secondEndWithinFirst = firstRange.offset + firstRange.length >= secondRange.offset + secondRange.length;

  return secondStartWithinFirst && secondEndWithinFirst;
};

var latestStyleLast = function latestStyleLast(s1, s2) {
  // make sure longer-lasting styles are added first
  var s2endIndex = s2.offset + s2.length;
  var s1endIndex = s1.offset + s1.length;
  return s2endIndex - s1endIndex;
};

var getStylesToReset = function getStylesToReset(remainingStyles, newStyles) {
  var i = 0;
  while (i < remainingStyles.length) {
    if (newStyles.every(rangeIsSubset.bind(null, remainingStyles[i]))) {
      i++;
    } else {
      return remainingStyles.slice(i);
    }
  }
  return [];
};

var appendStartMarkup = function appendStartMarkup(inlineHTML, string, styleRange) {
  return string + (0, _getElementHTML2.default)(inlineHTML(styleRange.style)).start;
};

var prependEndMarkup = function prependEndMarkup(inlineHTML, string, styleRange) {
  return (0, _getElementHTML2.default)(inlineHTML(styleRange.style)).end + string;
};

var defaultCustomInlineHTML = function defaultCustomInlineHTML(next) {
  return function (style) {
    return next(style);
  };
};
defaultCustomInlineHTML.__isMiddleware = true;

exports.default = function (rawBlock) {
  var customInlineHTML = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : defaultCustomInlineHTML;

  (0, _invariant2.default)(rawBlock !== null && rawBlock !== undefined, 'Expected raw block to be non-null');

  var inlineHTML = void 0;
  if (customInlineHTML.__isMiddleware === true) {
    inlineHTML = customInlineHTML(_defaultInlineHTML2.default);
  } else {
    inlineHTML = (0, _accumulateFunction2.default)((0, _styleObjectFunction2.default)(customInlineHTML), (0, _styleObjectFunction2.default)(_defaultInlineHTML2.default));
  }

  var result = '';
  var styleStack = [];

  var sortedRanges = rawBlock.inlineStyleRanges.sort(_rangeSort2.default);

  for (var i = 0; i < rawBlock.text.length; i++) {
    var styles = characterStyles(i, sortedRanges);

    var endingStyles = subtractStyles(styleStack, styles);
    var newStyles = subtractStyles(styles, styleStack);
    var remainingStyles = subtractStyles(styleStack, endingStyles);

    // reset styles: look for any already existing styles that will need to
    // end before styles that are being added on this character. to solve this
    // close out those current tags and all nested children,
    // then open new ones nested within the new styles.
    var resetStyles = getStylesToReset(remainingStyles, newStyles);

    var openingStyles = resetStyles.concat(newStyles).sort(latestStyleLast);

    var openingStyleTags = openingStyles.reduce(appendStartMarkup.bind(null, inlineHTML), '');
    var endingStyleTags = endingStyles.concat(resetStyles).reduce(prependEndMarkup.bind(null, inlineHTML), '');

    result += endingStyleTags + openingStyleTags + rawBlock.text[i];

    styleStack = popEndingStyles(styleStack, resetStyles.concat(endingStyles));
    styleStack = styleStack.concat(openingStyles);

    (0, _invariant2.default)(styleStack.length === styles.length, 'Character ' + i + ': ' + (styleStack.length - styles.length) + ' styles left on stack that should no longer be there');
  }

  result = styleStack.reduceRight(function (res, openStyle) {
    return res + (0, _getElementHTML2.default)(inlineHTML(openStyle.style)).end;
  }, result);

  return result;
};