Userscript to TitleCapitalize Headings in StackEdit

gistfile1.js

// ==UserScript==
// @name         TitleCapitalize Headings in StackEdit
// @namespace    http://hibbard.eu/
// @version      0.1
// @description  Apply titlecapitalization to h2 and h3 headings in StackEdit.
// @description  Inspired muchly by Bruno Skvorc: http://www.sitepoint.com/implementing-titlecapitalization-stackedit/
// @author       James Hibbard
// @match        https://stackedit.io/editor*
// @copyright    2015, hibbard.eu
// @require      http://code.jquery.com/jquery-latest.js
// ==/UserScript==

var prepositions = ['a', 'abaft', 'aboard', 'about', 'above', 'absent', 'across', 'afore', 'after', 'against', 'along', 'alongside', 'amid', 'amidst', 'among', 'amongst', 'an', 'apropos', 'apud', 'around', 'as', 'aside', 'astride', 'at', 'athwart', 'atop', 'barring', 'before', 'behind', 'below', 'beneath', 'beside', 'besides', 'between', 'beyond', 'but', 'by', 'circa', 'concerning', 'despite', 'down', 'during', 'except', 'excluding', 'failing', 'following', 'for', 'from', 'given', 'in', 'including', 'inside', 'into', 'lest', 'like', 'mid', 'midst', 'minus', 'modulo', 'near', 'next', 'notwithstanding', 'of', 'off', 'on', 'onto', 'opposite', 'out', 'outside', 'over', 'pace', 'past', 'per', 'plus', 'pro', 'qua', 'regarding', 'round', 'sans', 'since', 'than', 'through', 'thru', 'throughout', 'thruout', 'till', 'times', 'to', 'toward', 'towards', 'under', 'underneath', 'unlike', 'until', 'unto', 'up', 'upon', 'versus', 'vs\.', 'vs', 'v\.', 'v', 'via', 'vice', 'with', 'within', 'without', 'worth'];
var articles = ['a', 'an', 'the'];
var conjunctions = ['and', 'but', 'for', 'so', 'nor', 'or', 'yet'];
var punct = "([!\"#$%&'()*+,./:;<=>?@[\\\\\\]^_`{|}~-]*)";
var all_lower_case = '(' + (prepositions.concat(articles).concat(conjunctions)).join('|') + ')';

var capitalize = function(title){
  var parts = [], split = /[:.;?!] |(?: |^)["Ò]/g, index = 0;

  title = title.replace(/[\u2018\u2019]/g, "'").replace(/[\u201C\u201D]/g, '"');

  while (true) {
    var m = split.exec(title);

    parts.push( title.substring(index, m ? m.index : title.length).replace(/\b([A-Za-z][a-z.'Õ]*)\b/g, function(all){
      return /[A-Za-z]\.[A-Za-z]/.test(all) ? all : upper(all);
    })
    .replace(RegExp("\\b" + all_lower_case + "\\b", "ig"), lower)
    .replace(RegExp("^" + punct + all_lower_case + "\\b", "ig"), function(all, punct, word){
      return punct + upper(word);
    })
    .replace(RegExp("\\b" + all_lower_case + punct + "$", "ig"), upper));

    index = split.lastIndex;

    if ( m ) parts.push( m[0] );
    else break;
  }

  return parts.join("").replace(/ V(s?)\. /ig, " v$1. ")
  .replace(/(['Õ])S\b/ig, "$1s")
  .replace(/\b(AT&T|Q&A)\b/ig, function(all){
    return all.toUpperCase();
  });
};
 
function lower(word){
  return word.toLowerCase();
}
 
function upper(word){
  return word.substr(0,1).toUpperCase() + word.substr(1);
}

setTimeout(function(){
  var $lastButton = $("ul.left-buttons").last();
  var $titleCaseButton = $lastButton.append($("<button />", {text: "TitleCapitalize"}));
  $titleCaseButton.on("click", function(){
    $(".h3, .h2").each(function(){
     var capitalized = capitalize($(this).text());
     $(this).text(capitalized); 
    });
  });
}, 1000);