Smart Home using ARTIK Cloud

var webSocketUrl = "wss://api.artik.cloud/v1.1/websocket?ack=true";
var device_id = "<Device ID here>"; //Enter the device ID here
var device_token = "<Device token here>"; //Enter the device token here

var WebSocket = require('ws');
var isWebSocketReady = false;
var ws = null;
var mraa = require('mraa'); //Low Level Skeleton Library for IO Communication on GNU/Linux platforms
var lcd = require('./lcd'); // Required to interface with LCD

// Define variables for IO pins connected to board
var relay = new mraa.Gpio(7); //Define a relay connected to D7 pin on the Grove Shield
relay.dir(mraa.DIR_OUT); //Make the relay pin as output pin
var statusLED = new mraa.Gpio(3); //Define a LED connected to D3 pin on the Grove Shield
statusLED.dir(mraa.DIR_OUT); //Make the LED pin as output pin
var roomtemp = new mraa.Aio(0); // Measure the temperature with sensor connected to A0 pin on the Grove Shield
var intlight = new mraa.Aio(1); // Measure the light intensity with sensor connected to A1 pin on the Grove Shield
var relayState = 0; // The state of the relay
var display = new lcd.LCD(0);

/**
 * Gets the current time in millis
 */
function getTimeMillis(){
    return parseInt(Date.now().toString());
}

/**
 * Create a /websocket connection
 */
function start() {
    //Create the WebSocket connection
    isWebSocketReady = false;
    ws = new WebSocket(webSocketUrl);
    ws.on('open', function() {
        console.log("WebSocket connection is open ....");
        register(); //If the websocket connect is available the function is called to register on the Artik Cloud
    });
    ws.on('message', function(data) {
         handleRcvMsg(data); //The function is called and received data from the cloud is passed on to be processed
    });
    ws.on('close', function() {
        console.log("WebSocket connection is closed ....");
    });
}

/**
 * Sends a register message to /websocket endpoint
 */
function register(){
    console.log("Registering device on the WebSocket connection");
    try{
        var registerMessage = '{"type":"register", "sdid":"'+device_id+'", "Authorization":"bearer '+device_token+'", "cid":"'+getTimeMillis()+'"}'; //The format to register the device on the Artik Cloud
        console.log('Sending register message ' + registerMessage + '\n');
        ws.send(registerMessage, {mask: true});
        isWebSocketReady = true;
    }
    catch (e) {
        console.error('Failed to register messages. Error in registering message: ' + e.toString());
       
    }    
}

//Handle the received message from the Artik Cloud
function handleRcvMsg(msg){
    var msgObj = JSON.parse(msg);
    if (msgObj.type != "action") return; //Early return;

    var actions = msgObj.data.actions; //From the data received get the received actions
    var actionName = actions[0].name; //assume that there is only one action in actions
    console.log("The received action is " + actionName);
    var newState;
    if (actionName.toLowerCase() == "seton") {
        newState = 1; //If the received action is to 'seton' then switch on the relay
    }
    else if (actionName.toLowerCase() == "setoff") {
        newState = 0; //If the received action is to 'setoff' then switch off the relay
    } else {
        console.log('Do nothing since receiving unrecognized action ' + actionName);
        return;
    }
    togglerelay(newState); //The function is called to toggle the relay based on the passed state
}

function togglerelay(value) {
     
        relayState = value;
        relay.write(value);
        console.log('togglerelay: wrote ' + value + ' to pin #' + relay);
        sendRelayStateToArtikCloud(); //Call the function to send the relay state data to Artik Cloud
    }

//Send relay state data to the Artik Cloud
function sendRelayStateToArtikCloud(){
    try{
        ts = ', "ts": '+getTimeMillis();
        var data = {
              "state": relayState /* Here the 'state' of the relay is set to the variable relayState. Note that the word 'state' should match exactly with the Artik Cloud Device manifest */
            };
        var payload = '{"sdid":"'+device_id+'"'+ts+', "data": '+JSON.stringify(data)+', "cid":"'+getTimeMillis()+'"}';
        console.log('Sending payload ' + payload + '\n'); //Format to send data to the Artik Cloud
        ws.send(payload, {mask: true});
    } catch (e) {
        console.error('Error in sending a message: ' + e.toString() +'\n');
        
    }    
}

//After a delay read the value from the input pin and calculate the temperature
setInterval(function () {

        var a = roomtemp.read();
        var resistance = (1023 - a) * 10000 / a; 
        var celsius_temperature = 1 / (Math.log(resistance / 10000) / 3975 + 1 / 298.15) - 273.15;
        console.log("Celsius Temperature: " + celsius_temperature);
        sendRoomTempToArtikCloud(celsius_temperature); //Call the function and pass on the temperature value to be sent to the Artik Cloud
        display.setCursor(0, 0);
    
        display.write('Temperature:'+ celsius_temperature);
      }, 15000);

//Send the room temperature data to the Artik Cloud
function sendRoomTempToArtikCloud(temp){
    try{
        ts = ', "ts": '+getTimeMillis();
        var data = {
            "currentTemp": temp
        };
        var payload = '{"sdid":"'+device_id+'"'+ts+', "data": '+JSON.stringify(data)+', "cid":"'+getTimeMillis()+'"}';
       
        ws.send(payload, {mask: true});
    } catch (e) {
        console.error('Error in sending a message: ' + e.toString());
    }   
   
}

//After a delay read the light intensity value from the input pin
setInterval(function () {

        var b = intlight.read();
        console.log("Light Intensity: " + b);
        sendLightIntensityToArtikCloud(b);
        display.setCursor(1, 0);
        if(b<100){
          display.write('Light Int:0'+b); //LCD had some problem displaying two figures correctly so this is the work around
        }
        else{
          display.write('Light Int:'+b);  
        }
        
      }, 15000);

//Send the light intensity data to the Artik Cloud
function sendLightIntensityToArtikCloud(lightint){
    try{
        ts = ', "ts": '+getTimeMillis();
        var data = {
            "currentlightint": lightint
        };
        var payload = '{"sdid":"'+device_id+'"'+ts+', "data": '+JSON.stringify(data)+', "cid":"'+getTimeMillis()+'"}';
       
        ws.send(payload, {mask: true});
    } catch (e) {
        console.error('Error in sending a message: ' + e.toString());
        
    }   
}


/**
 * All start here
 */

start();