safari version detection

safariversiondetection.js

var oldSafari = (function() {
  var ua = window.navigator.userAgent;
  if(!/safari/i.test(ua)) {
    return false;
  }
  if(/chrome/i.test(ua)) {
    // chrome has 'Safari' in its ua.
    return false;
  }
  if(/mobile/i.test(ua)) {
    // ignore mobile safari.
    return false;
  }
  if(!/version\/\d/i.test(ua)) {
    // it must contain "Version/5.6.3" string
    return false;
  }
  var matched = ua.match(/version\/(\d+)/i);
  if(matched.length !== 2) {
    return false;
  }
  var version = matched[1]*1;
  return version < 5;
})();