Google Maps click event on route

var infowindow = new google.maps.InfoWindow();
var directions = new google.maps.DirectionsService();
var renderer = new google.maps.DirectionsRenderer({
  suppressPolylines: true,
  infoWindow: infowindow,
});
var map;

function initialize() {
  var mapOptions = {
    zoom: 13,
    center: new google.maps.LatLng(40.7482333, -73.8681295),
    mapTypeId: google.maps.MapTypeId.ROADMAP
  };

  map = new google.maps.Map(document.getElementById('map'), mapOptions);

  google.maps.event.addDomListener(document.getElementById('go'), 'click',
    route);

  var input = document.getElementById('from');
  var autocomplete = new google.maps.places.Autocomplete(input);
  autocomplete.bindTo('bounds', map);
  route();
}

function route() {
  var request = {
    origin: document.getElementById('from').value,
    destination: '51 St, New York, NY 10022, USA',
    travelMode: google.maps.DirectionsTravelMode.WALKING
  };

  var panel = document.getElementById('panel');
  panel.innerHTML = '';
  directions.route(request, function(response, status) {
    if (status == google.maps.DirectionsStatus.OK) {
      renderer.setDirections(response);
      renderer.setMap(map);
      renderer.setPanel(panel);
      renderDirectionsPolylines(response);
      console.log(renderer.getDirections());
    } else {
      renderer.setMap(null);
      renderer.setPanel(null);
    }

  });

}

var polylineOptions = {
  strokeColor: '#C83939',
  strokeOpacity: 1,
  strokeWeight: 4
};
var polylines = [];
function renderDirectionsPolylines(response) {
  for (var i=0; i<polylines.length; i++) {
    polylines[i].setMap(null);
  }
  var legs = response.routes[0].legs;
  for (i = 0; i < legs.length; i++) {
    var steps = legs[i].steps;
    for (j = 0; j < steps.length; j++) {
      var nextSegment = steps[j].path;
      var stepPolyline = new google.maps.Polyline(polylineOptions);
      for (k = 0; k < nextSegment.length; k++) {
        stepPolyline.getPath().push(nextSegment[k]);
      }
      polylines.push(stepPolyline);
      stepPolyline.setMap(map);
      // route click listeners, different one on each step
      google.maps.event.addListener(stepPolyline, 'click', function(evt) {
        infowindow.setContent("you clicked on the route<br>" + evt.latLng.toUrlValue(6));
        infowindow.setPosition(evt.latLng);
        infowindow.open(map);
      })
    }
  }
}
google.maps.event.addDomListener(window, 'load', initialize);

html,
body {
  height: 100%;
  padding: 0;
  margin: 0;
  color: black;
  font-family: arial, sans-serif;
  font-size: 13px;
}
#map {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 50%;
}
#panel-wpr {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  right: 0;
  overflow: auto;
}
#panel {
  font-family: arial;
  padding: 0 5px;
}
#info {
  padding: 5px;
}
#from {
  width: 90%;
  font-size: 1.2em;
}
.adp-directions {
  width: 100%;
}
.input {
  background-color: white;
  padding-left: 8px;
  border: 1px solid #D9D9D9;
  border-top: 1px solid silver;
  -webkit-border-radius: 1px;
  -moz-border-radius: 1px;
  border-radius: 1px;
}
.time {
  margin: 0;
  height: 17px;
  border: 1px solid;
  border-top-color: #CCC;
  border-right-color: #999;
  border-left-color: #999;
  border-bottom-color: #CCC;
  padding: 2px 15px 1px 1px;
}
button {
  border: 1px solid #3079ED;
  color: white;
  background-color: #4D90FE;
  background-image: -webkit-gradient(linear, left top, left bottom, from(#4D90FE), to(#4787ED));
  background-image: -webkit-linear-gradient(top, #4D90FE, #4787ED);
  background-image: -moz-linear-gradient(top, #4D90FE, #4787ED);
  background-image: -ms-linear-gradient(top, #4D90FE, #4787ED);
  background-image: -o-linear-gradient(top, #4D90FE, #4787ED);
  background-image: linear-gradient(top, #4D90FE, #4787ED);
  filter: progid: DXImageTransform.Microsoft.gradient(startColorStr="#4d90fe", EndColorStr="#4787ed");
  display: inline-block;
  min-width: 54px;
  text-align: center;
  font-weight: bold;
  padding: 0 8px;
  line-height: 27px;
  -webkit-border-radius: 2px;
  -moz-border-radius: 2px;
  border-radius: 2px;
  -webkit-transition: all 0.218s;
  -moz-transition: all 0.218s;
  -o-transition: all 0.218s;
  transition: all 0.218s;
}
#info div {
  line-height: 22px;
  font-size: 110%;
}
.btn {} #panel-wpr {
  border-left: 1px solid #e6e6e6;
}
#info {
  border-bottom: 1px solid #E6E6E6;
  margin-bottom: 5px;
}
h2 {
  margin: 0;
  padding: 0;
}

<script src="https://maps.googleapis.com/maps/api/js?libraries=places&key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk"></script>
<title>Google Maps JavaScript API v3 Example: Transit</title>
<div id="transit-wpr">
  <button id="transit">Toggle transit layer</button>
</div>
<div id="map"></div>
<div id="panel-wpr">
  <div id="info">
    <div>
      <label>from:</label>
      <input class="input" id="from" value="Grand Central 42, NY">
    </div>
    <div>
      <label>to:</label>
      <strong>51 St, New York, NY 10022, USA</strong>
    </div>
    <div class="btn">
      <button id="go">Get Directions</button>
    </div>
  </div>
  <div id="panel"></div>
</div>