mess up text

mess.js

"use strict";

$(function(){

  var getTextNodesIn = function(el) {
    return $(el).find(":not(iframe)").addBack().contents().filter(function() {
      return this.nodeType == 3;
    });
  };

  // var textNodes = getTextNodesIn($("p, h1, h2, h3"));
  var textNodes = getTextNodesIn($("*"));



  function isLetter(char) {
    return /^[\d]$/.test(char);
  }


  var wordsInTextNodes = [];
  for (var i = 0; i < textNodes.length; i++) {
    var node = textNodes[i];

    var words = []

    var re = /\w+/g;
    var match;
    while ((match = re.exec(node.nodeValue)) != null) {

      var word = match[0];
      var position = match.index;

      words.push({
        length: word.length,
        position: position
      });
    }

    wordsInTextNodes[i] = words;
  };


  function messUpWords () {

    for (var i = 0; i < textNodes.length; i++) {

      var node = textNodes[i];

      for (var j = 0; j < wordsInTextNodes[i].length; j++) {

        // Only change a tenth of the words each round.
        if (Math.random() > 1/10) {

          continue;
        }

        var wordMeta = wordsInTextNodes[i][j];

        var word = node.nodeValue.slice(wordMeta.position, wordMeta.position + wordMeta.length);
        var before = node.nodeValue.slice(0, wordMeta.position);
        var after  = node.nodeValue.slice(wordMeta.position + wordMeta.length);

        node.nodeValue = before + messUpWord(word) + after;
      };
    };
  }

  function messUpWord (word) {

    if (word.length < 3) {

      return word;
    }

    return word[0] + messUpMessyPart(word.slice(1, -1)) + word[word.length - 1];
  }

  function messUpMessyPart (messyPart) {

    if (messyPart.length < 2) {

      return messyPart;
    }

    var a, b;
    while (!(a < b)) {

      a = getRandomInt(0, messyPart.length - 1);
      b = getRandomInt(0, messyPart.length - 1);
    }

    return messyPart.slice(0, a) + messyPart[b] + messyPart.slice(a+1, b) + messyPart[a] + messyPart.slice(b+1);
  }

  // From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/random
  function getRandomInt(min, max) {
    
    return Math.floor(Math.random() * (max - min + 1) + min);
  }


  setInterval(messUpWords, 50);
});