index.js, Annotated

// WebSocket connection setup
var socket = io();
var questionRecieved=false;
var output = document.getElementById('output');	
output.innerHTML = "<h1 id=response </h1>";

variable declaration of the objects that need to be addressed frqeuntly or that need to be kept track of during one session.

1. with socket = io(); we create a socket client that will connect back to the node.js server running ChatServer.js
2. questionRecieved keeps track of whether or not we have recieved a question, to avoid sending empty or unwanted messages
3. The output object is the response field from the ChatBot that needs to be freqeuntly changed

function sendMessage() {
    var input = document.getElementById("input").value;
    socket.emit('message',input);
    document.getElementById("input").value="";
    document.getElementById("input").style.display="none";
}

This function is called to send answers to the server.

1. reads the written message
2. sends it over the socket connection to the server with socket.emit(...)
3. empties the text field and...
4. ... finally turns the field invisible with .style.display="none"

$(document).keypress(function(e) {
  if (e.which == 13 && questionRecieved===true) {
    questionRecieved=false;
    sendMessage();// run bot function when enter key pressed
  }
});

This function is called when an 'return-key' press is detected.

function changeText(input){
document.getElementById('response').textContent = input;
}

This function is called whenever the response from the ChatBot on the webpage needs to be changed. It finds the correct object with the 'response' ID and changes the .textContent

socket.on('answer', function(msg) {
  console.log('Incomming answer:', msg);
  changeText(msg);
});
socket.on('question', function(msg) {
  console.log('Incomming Question:', msg);
  questionRecieved=true;
  document.getElementById("input").style.display="block";
  changeText(msg);
});
socket.on('changeBG', function(msg) {
  console.log('Changeing backgroundColor to:', msg);
  document.body.style.backgroundColor = msg;
});
socket.on('changeFont', function(msg) {
  console.log('Changeing Font to:', msg);
  var h1 = document.getElementById('response');
  h1.style.color = 'white';
});

These four functions correspond to strict messages that the server can send to the client. The first element of this function is the type of message (e.g. changeFont) and the second part is the function to execute when such a message is recieved e.g. function(msg) { console.log('Changeing Font to:', msg); ...

socket.on('connect',function(){
  socket.emit('loaded');
});

This function is similar to the above. It is a workaround function to make sure that the server-client connection is running and stable before the server starts sending messages.