jquery.sniffVisited.js

// Sniff out visited links by a user with jQuery
// by Greg Leuch <http://www.gleuch.com>

// based on an initial idea from Jonathan Snook <http://snook.ca>
// idea: <http://twitter.com/snookca/status/1121377463>

// Note: Only works if user has browser history enabled (save history for x >0 days)

// Edit: looks like my code mimics same idea that Aza Raskin's SocialHistory.js does, sans iframe and visit color matching. <http://www.azarask.in/blog/post/socialhistoryjs/>


(function($) {
  $.sniffVisited = function() {
    if (!$.sniffVisited.init) {
      $.sniffVisited.domain = window.location.href.replace(/^([a-z]*)(:\/\/)([a-z0-9\-\_\.\:\@]*)(.*)$/i, '$1$2$3');
      if ($('style#style_'+ $.sniffVisited.id).size() < 1) $('body').append('<style id="style_'+ $.sniffVisited.id +'" type="text/css">#links_'+ $.sniffVisited.id +' {display: none;} body a:visited {counter-increment: '+ $.sniffVisited.match +';}</style>');
      if ($('div#links_'+ $.sniffVisited.id).size() < 1) $('body').append('<div id="links_'+ $.sniffVisited.id +'"></div>');
      jQuery($.sniffVisited.against).each($.sniffVisited.test);
    }
    $('a').filter($.sniffVisited.filter).each($.sniffVisited.add);
 
    // Sniff internal links...
    if ($.sniffVisited.history.local.length > 0) alert("Internal pages:\n\n"+ jQuery.unique($.sniffVisited.history.local).join("\n"));
    // Sniff external links...
    if ($.sniffVisited.history.external.length > 0) alert("External pages:\n\n"+ jQuery.unique($.sniffVisited.history.external).join("\n"));
  }
  $.extend($.sniffVisited, {
    init : false,
    domain : false,
    id : 'jquery_sniffVisited',
    match : 'visited',
    against : ['facebook.com', 'twitter.com', 'youtube.com', 'vimeo.com', 'tumblr.com'],
    history : {local : [], external : []},
    test : function(i) {$('#links_'+ $.sniffVisited.id).append('<a href="http://www.'+ this +'/" /><a href="http://'+ this +'/" /><a href="https://www.'+ this +'/" /><a href="https://'+ this +'/" />');},      
    add : function() {(this.href.indexOf($.sniffVisited.domain) >= 0 ? $.sniffVisited.history.local : $.sniffVisited.history.external).push(this.href);},
    filter : function() {return /visited/i.test($(this).css('counter-increment'));}
  });
})(jQuery);

// Call sniffer
$(document).ready(function() {$.sniffVisited();});