Highlight words in html with a jquery plugin using jquery methods rather than raw DOM.

JQuery Highlighter .js

/* 
* HTML Highlighter
*/
(function($){
  $.fn.highlight = function(words, options){
    var elements = $(this) 
      , settings = {
          className: 'highlight'
          , caseSensitive: false
        }
      , term = function(x){
          if (!settings.caseSensitive)
            return x.toLowerCase()
          return x  
        }  
            
    $.extend(settings, options || {})
  
    if (typeof words === 'string')
        words = [words]
      
    
    $.each(elements, function(){
      var $element = $(this).children().highlight(words)
      
      $.each(words, function(i, word){
        word = term(word)
        $element    
          .contents()
          .filter(function(){ // Text node && matches 
            return this.nodeType === 3 && term(this.data).indexOf(word) > -1 
            })
          .each(function(){
            var ind = term(this.data).indexOf(word)
              , len = word.length
              , pre = $('<span />').text(this.data.substring(0, ind))
              , text = $('<span />')
                .text(this.data.substring(ind, ind + len))
                .addClass(settings.className)
              , post =  $('<span />').text(this.data.substring(ind+len))

            $(this).replaceWith(pre.after(text).after(post))
              
          })
      })
    })    
    return elements
  }

}(jq));