#define BLYNK_TEMPLATE_ID "TMPL3pBWjDIrQ"
#define BLYNK_TEMPLATE_NAME "smart city"
#define BLYNK_AUTH_TOKEN "mao9DOaEqiyn5coZ2hr4iC0cZW5tAEAl"

#include <WiFi.h>
#include <BlynkSimpleEsp32.h>


char auth[] = BLYNK_AUTH_TOKEN;
const char* ssid = "Wokwi-GUEST";
const char* password = "";





#include <DHT.h>

#define DHTPIN 15       // GPIO15
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

// Pins for Ultrasonic Sensor
#define TRIG_PIN 13
#define ECHO_PIN 12

#define RELAY_PIN 26


#define GAS_THRESHOLD_HIGH 550
#define GAS_THRESHOLD_LOW  450
int usageCount = 0;
bool previousIRState = false;
bool buzzerState = false;

// Pins for LEDs
#define RED_LED 14
#define YELLOW_LED 27
#define GREEN_LED 26

// IR Sensor pin
#define IR_SENSOR_PIN 18

// MQ Sensor (analog)
#define MQ_SENSOR_PIN 34
BLYNK_WRITE(V4) {
  int state = param.asInt();
  digitalWrite(RELAY_PIN, state);
}

BLYNK_WRITE(V6) {
  digitalWrite(RED_LED, param.asInt());
}

BLYNK_WRITE(V7) {
  digitalWrite(YELLOW_LED, param.asInt());
}

BLYNK_WRITE(V8) {
  digitalWrite(GREEN_LED, param.asInt());
}





// Relay
void setup() {
  Serial.begin(9600);
  dht.begin();
  Blynk.begin(auth, ssid, password);

  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);

  pinMode(RED_LED, OUTPUT);
  pinMode(YELLOW_LED, OUTPUT);
  pinMode(GREEN_LED, OUTPUT);

  pinMode(IR_SENSOR_PIN, INPUT);
  pinMode(MQ_SENSOR_PIN, INPUT);
  pinMode(RELAY_PIN, OUTPUT);
}

void loop() {

  Blynk.run();
  // DHT22 Reading
  float temp = dht.readTemperature();
  float hum = dht.readHumidity();

  Serial.print("Temperature: ");
  Serial.print(temp);
  Serial.print("°C, Humidity: ");
  Serial.print(hum);
  Serial.println("%");

  // Ultrasonic Distance Measurement
  long duration, distance;
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = duration * 0.034 / 2;

  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Set LED based on distance
  if (distance < 10) {
    digitalWrite(RED_LED, HIGH);
    digitalWrite(YELLOW_LED, LOW);
    digitalWrite(GREEN_LED, LOW);
  } else if (distance < 20) {
    digitalWrite(RED_LED, LOW);
    digitalWrite(YELLOW_LED, HIGH);
    digitalWrite(GREEN_LED, LOW);
  } else {
    digitalWrite(RED_LED, LOW);
    digitalWrite(YELLOW_LED, LOW);
    digitalWrite(GREEN_LED, HIGH);
  }
 
  


 // --- IR Sensor for Usage Count ---
  bool currentIRState = digitalRead(IR_SENSOR_PIN) == LOW;

  if (currentIRState && !previousIRState) {
    usageCount++;
    Serial.print("Usage Count: ");
    Serial.println(usageCount);
  }

  previousIRState = currentIRState;

  // Read MQ sensor (simplified logic)
  int mqValue = analogRead(MQ_SENSOR_PIN);
  Serial.print("MQ Sensor Value: ");
  Serial.println(mqValue);

  // Relay logic based on gas level or temperature


if (!buzzerState && mqValue > GAS_THRESHOLD_HIGH) {
  digitalWrite(RELAY_PIN, HIGH);
  buzzerState = true;
  Serial.println("Buzzer: ON (Gas Detected)");
} else if (buzzerState && mqValue < GAS_THRESHOLD_LOW) {
  digitalWrite(RELAY_PIN, LOW);
  buzzerState = false;
  Serial.println("Buzzer: OFF (Gas Normal)");
}

  Blynk.virtualWrite(V0, temp);
  Blynk.virtualWrite(V1, hum);
  Blynk.virtualWrite(V2, mqValue);
  Blynk.virtualWrite(V5, distance);

  
delay(2000);
}