process.js

var rnProcess = require('react-native-dynamic-style-processor').process;

var isArray = Array.isArray || function(arg) {
  return Object.prototype.toString.call(arg) === '[object Array]';
};

exports.process = function processStyleName(styleName, cssStyles) {
  cssStyles = rnProcess(cssStyles);

  // Process styleName through the `classnames`-like function.
  // This allows to specify styleName as an array or an object,
  // not just the string.
  styleName = cc(styleName);

  var htmlClasses = (styleName || '').split(' ').filter(Boolean);
  if (htmlClasses.length > 1) {
    htmlClasses = addMultiClasses(htmlClasses, cssStyles);
  }
  var res = [];
  for (var i = 0; i < htmlClasses.length; i++) {
    var htmlClass = htmlClasses[i];
    if (cssStyles[htmlClass]) res.push(cssStyles[htmlClass]);
  }
  return res;
};

function addMultiClasses(htmlClasses, cssStyles) {
  var selectors = Object.keys(cssStyles);
  var resByAmount = {};
  var maxAmount = 0;
  for (var i = 0; i < selectors.length; i++) {
    var selector = selectors[i];
    if (!/\./.test(selector)) continue;
    var cssClasses = selector.split('.');
    if (arrayContainedInArray(cssClasses, htmlClasses)) {
      var amount = cssClasses.length;
      if (amount > maxAmount) maxAmount = amount;
      if (!resByAmount[amount]) resByAmount[amount] = [];
      resByAmount[amount].push(selector);
    }
  }
  for (var j = 0; j <= maxAmount; j++) {
    if (!resByAmount[j]) continue;
    htmlClasses = htmlClasses.concat(resByAmount[j]);
  }
  return htmlClasses;
};

function arrayContainedInArray(cssClasses, htmlClasses) {
  for (var i = 0; i < cssClasses.length; i++) {
    if (htmlClasses.indexOf(cssClasses[i]) === -1) return false;
  }
  return true;
};

// classcat 4.0.2
// https://github.com/jorgebucaran/classcat

function cc(names) {
  var i;
  var len;
  var tmp = typeof names;
  var out = "";

  if (tmp === "string" || tmp === "number") return names || "";

  if (isArray(names) && names.length > 0) {
    for (i = 0, len = names.length; i < len; i++) {
      if ((tmp = cc(names[i])) !== "") out += (out && " ") + tmp;
    }
  } else {
    for (i in names) {
      if (names.hasOwnProperty(i) && names[i]) out += (out && " ") + i;
    }
  }

  return out;
}