Task 3.3D

// Required Libraries
#include <WiFiNINA.h>
#include <ArduinoMqttClient.h>
#include "NewPing.h"

// Retrieve SSID and PASS from Secrets tab
char ssid[] = SECRET_SSID;
char pass[] = SECRET_OPTIONAL_PASS; 

// Declare pin identities
const int ledPin = 2;
const int trigPin = 3;
const int echoPin = 3;

// Create NewPing instance
NewPing sonar(trigPin, echoPin);

// Create WiFI and MQTT clients
WiFiClient wifiClient;
MqttClient mqttClient(wifiClient);

// Set values of MQTT
const char broker[] = "broker.emqx.io";
int        port = 1883;
const char wave[] = "SIT210/wave";
const char pat[] = "SIT210/pat";

// Set variables
int distance = 0;
bool wave_detected = false;
bool pat_detected = false;

void setup() 
{  
  // Initialize serial and wait for port to open
  Serial.begin(9600);
  while (!Serial);
  delay(1500); 

  // Initialize WiFi connection
  Serial.println("Attempting to connect to SSID: ");
  Serial.println(ssid);
  while (WiFi.begin(ssid, pass) != WL_CONNECTED)
  {
    Serial.print(".");
    delay(5000);
  }
  Serial.println();
  Serial.println("Connection successful");

  // Initialize MQTT connection
  Serial.print("Attempting to connect to the MQTT broker: ");
  Serial.println(broker);
  if (!mqttClient.connect(broker, port))
  {
    Serial.print("MQTT connection failed! Error code = ");
    Serial.println(mqttClient.connectError());
    while (1);
  }
  Serial.println();
  Serial.println("Connection successful");

  // Subscripe to desired topics
  mqttClient.subscribe(pat);
  mqttClient.subscribe(wave);
  
  // Initialize pins
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ledPin, OUTPUT);
}

void loop() 
{
  mqttClient.poll();
  delay(500);

  distance = sonar.ping_cm();
  Serial.print("Distance = ");
  Serial.print(distance);
  Serial.println("cm");

  if (distance <= 30 && distance > 5)
  {        
    mqttClient.beginMessage(wave);
    mqttClient.println(wave);
    mqttClient.print("*waved*");
    mqttClient.endMessage();
    delay(500);
    wave_detected = true;
  }
  else if (distance <= 5)
  {
    mqttClient.beginMessage(pat);
    mqttClient.println(pat);
    mqttClient.print("*patted*");
    mqttClient.endMessage();
    delay(500);
    pat_detected = true;
  }

  if(wave_detected || pat_detected )
  {
    int Msize = mqttClient.parseMessage();
    Serial.print(Msize);
    if (Msize)
    {
      Serial.println();
      Serial.print("Received message with the subject ");
      Serial.print(mqttClient.messageTopic());
      Serial.print(", length ");
      Serial.print(Msize);
      Serial.println(" bytes:");
  
      while (mqttClient.available())
      {
        Serial.print((char)mqttClient.read());
      }
      Serial.println();

      if (wave_detected)
      {
        for (int i = 0; i < 3; i++)
        {
          digitalWrite(ledPin, HIGH);
          delay(200);
          digitalWrite(ledPin, LOW);
          delay(100);
        }
         wave_detected = false;
      }
      if (pat_detected)
      {
        for (int i = 0; i < 2; i++)
        {
          digitalWrite(ledPin, HIGH);
          delay(200);
          digitalWrite(ledPin, LOW);
          delay(100);
          digitalWrite(ledPin, HIGH);
          delay(500);
          digitalWrite(ledPin, LOW);
          delay(100);
        }
         pat_detected = false;
      }
      Serial.println();
    }
  }
}