/*  Lab Trial Test 1
   *  Name: TINAGARAN 
    * Class: Iot
   *  Date: 10/1/25
  */

#include <WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>

#define TRIG_PIN 2     // Ultrasonic Trigger Pin
#define ECHO_PIN 18    // Ultrasonic Echo Pin
#define LED_PIN 23     // Red LED for full bin indicator

int ledPin = 16;                // choose the pin for the LED
int inputPin = 21;               // choose the input pin (for PIR sensor)
int pirState = LOW;             // we start, assuming no motion detected
int val = 0;                    // variable for reading the pin status

int LEDstate_R= 1;
long previousMillis_R = 0;
int interval_R = 2000;
char red_led = 23;

const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* hostname = "broker.hivemq.com";

WiFiClient espClient;
PubSubClient client(espClient);
const char* espClientName = "esp32Client_TINAGARAN"; // yourStudentID must be unique
int PORTNUM = 1883;

void MQTTSubscribe() 
{
}

void connectMQTT()
{
  while(!client.connected() )
  {
    Serial.println("Connecting to MQTT ...");
    if (client.connect(espClientName) ) //, mqttUser, mqttPassword) )
    {
      Serial.println("Connected");
      MQTTSubscribe();
    }
    else
    {
      Serial.print("Failed with state ");
      Serial.print(client.state() );
      delay(2000);
    }
  }
}

void setup_wifi()
{
  WiFi.begin(ssid, password);
  while(WiFi.status() != WL_CONNECTED )
  {
    delay(1000);
    Serial.print(".");
  }
  Serial.println();
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("Given IP by the router to ESP32 is ");
  Serial.println(WiFi.localIP());
}



void callback(String topic, byte* payload, unsigned int length)
{
  String messageTemp;
  Serial.print("Message received in topic: ");
  Serial.print(topic);
  Serial.print(" length is: ");
  Serial.println(length);

  Serial.print("Data received from broker: ");
  for (int i = 0; i<length; i++)
  {
    Serial.print( (char)payload[i] );
    messageTemp += (char)payload[i];
  }

/// Handle your topics and payload here
}
long readDistance() {
    digitalWrite(TRIG_PIN, LOW);
    delayMicroseconds(2);
    digitalWrite(TRIG_PIN, HIGH);
    delayMicroseconds(10);
    digitalWrite(TRIG_PIN, LOW);
    return pulseIn(ECHO_PIN, HIGH) * 0.034 / 2; // Convert to cm
}



void setup_MQTT() 
{
  client.setServer(hostname, PORTNUM);
  client.setCallback(callback);
}

void setup()
{

 Serial.begin(9600);
 pinMode(TRIG_PIN, OUTPUT);
 pinMode(ECHO_PIN, INPUT);
 pinMode(LED_PIN, OUTPUT);

 pinMode(ledPin, OUTPUT);      // declare LED as output
 pinMode(inputPin, INPUT);     // declare sensor as input



 pinMode(red_led,OUTPUT);

 setup_wifi();
 setup_MQTT();
 
 
}

void loop()
{
   if ( !client.connected() )
  {
    connectMQTT();
  }
  client.loop();

   

  long distance = readDistance();
    Serial.print("Distance: ");
    Serial.println(distance);

    if (distance > 300) {
        digitalWrite(LED_PIN, LOW); // Turn on red LED
        Serial.println("MQTT Publish: Dustbin is Full");
        client.publish("iot/3164479r" ,"On");
    } else {
        digitalWrite(LED_PIN, HIGH); // Turn off red LED
        Serial.println("MQTT Publish: Dustbin is not Full");
        client.publish("iot/3164479r" ,"Off");
       
    }

    delay(5000);

  {
  val = digitalRead(inputPin);  // read input value
  if (val == HIGH) {            // check if the input is HIGH
    digitalWrite(ledPin, HIGH);  // turn LED ON
    if (pirState == LOW) {
      // we have just turned on
      Serial.println("Motion detected!");
      // We only want to print on the output change, not state
      pirState = HIGH;
    }
  } else {
    digitalWrite(ledPin, LOW); // turn LED OFF
    if (pirState == HIGH) {
      // we have just turned of
      Serial.println("Motion ended!");
      // We only want to print on the output change, not state
      pirState = LOW;
    }
  }
}
}