#include <ESP32Servo.h>
#include <DHT.h>

// LED pins
#define LED1 14
#define LED2 12
#define LED3 13

// PIR sensor pins
#define PIR1 22
#define PIR2 23
#define PIR3 26

// Ultrasonic sensor pins
#define TRIG1 2
#define ECHO1 4
#define TRIG2 5
#define ECHO2 18
#define TRIG3 19
#define ECHO3 21

// Servo pins
#define SERVO1_PIN 27
#define SERVO2_PIN 32
#define SERVO3_PIN 33

// Flame Sensor pins
#define LDR1_PIN 34
#define LDR2_PIN 35
#define LDR3_PIN 36

// Buzzer pin
#define BUZZER 15

// DHT22 sensor pin
#define DHTPIN 25
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

// Threshold for flame detection
const int flameThreshold = 800;

// Detection range for ultrasonic sensors
const int detectionRange = 20;

// Delay time
const int delayTime = 5000;

// Servo objects
Servo servo1;
Servo servo2;
Servo servo3;

// Variables to track detection status
bool isPersonDetected1 = false;
bool isPersonDetected2 = false;
bool isPersonDetected3 = false;

// Function to measure distance using an ultrasonic sensor
long measureDistance(int trigPin, int echoPin) {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  long duration = pulseIn(echoPin, HIGH);
  long distance = duration * 0.034 / 2; 
  return distance;
}

void setup() {
  Serial.begin(115200);

  // Initialize LEDs
  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);
  digitalWrite(LED1, LOW);
  digitalWrite(LED2, LOW);
  digitalWrite(LED3, LOW);

  // Initialize PIR sensors
  pinMode(PIR1, INPUT);
  pinMode(PIR2, INPUT);
  pinMode(PIR3, INPUT);

  // Initialize ultrasonic sensors
  pinMode(TRIG1, OUTPUT);
  pinMode(ECHO1, INPUT);
  pinMode(TRIG2, OUTPUT);
  pinMode(ECHO2, INPUT);
  pinMode(TRIG3, OUTPUT);
  pinMode(ECHO3, INPUT);

  // Initialize buzzer
  pinMode(BUZZER, OUTPUT);
  digitalWrite(BUZZER, LOW);

  // Attach servos to pins
  servo1.attach(SERVO1_PIN);
  servo2.attach(SERVO2_PIN);
  servo3.attach(SERVO3_PIN);

  // Initialize servos to 0 degrees
  servo1.write(0);
  servo2.write(0);
  servo3.write(0);

  // Initialize DHT22 sensor
  dht.begin();

 
}

void loop() {
  // Read temperature and humidity from DHT22
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();

  // Check if DHT readings are valid
  if (isnan(temperature) || isnan(humidity)) {
    Serial.println("Failed to read from DHT sensor!");
  } else {
    Serial.print("Temperature: ");
    Serial.print(temperature);
    Serial.println(" °C");
    Serial.print("Humidity: ");
    Serial.print(humidity);
    Serial.println(" %");
  }
  int motion1 = digitalRead(PIR1);
  int motion2 = digitalRead(PIR2);
  int motion3 = digitalRead(PIR3);

  // Control LEDs based on PIR sensors
  digitalWrite(LED1, motion1 ? HIGH : LOW);
  digitalWrite(LED2, motion2 ? HIGH : LOW);
  digitalWrite(LED3, motion3 ? HIGH : LOW);

  // Ultrasonic sensor and servo control logic
  controlServoWithDelay(TRIG1, ECHO1, servo1, isPersonDetected1);
  controlServoWithDelay(TRIG2, ECHO2, servo2, isPersonDetected2);
  controlServoWithDelay(TRIG3, ECHO3, servo3, isPersonDetected3);

  // Read LDR values for flame detection
  int ldr1Value = analogRead(LDR1_PIN);
  int ldr2Value = analogRead(LDR2_PIN);
  int ldr3Value = analogRead(LDR3_PIN);

  // Detect flame using LDR values and activate buzzer
  bool flameDetected = false;

  if (ldr1Value < flameThreshold) {
    Serial.println("Flame Detected in Room 1!");
    flameDetected = true;
  }
  if (ldr2Value < flameThreshold) {
    Serial.println("Flame Detected in Room 2!");
    flameDetected = true;
  }
  if (ldr3Value < flameThreshold) {
    Serial.println("Flame Detected in Room 3!");
    flameDetected = true;
  }

  if (flameDetected) {
    digitalWrite(BUZZER, HIGH); // Activate buzzer
  } else {
    digitalWrite(BUZZER, LOW); // Deactivate buzzer
  }

  delay(100); // Small delay to stabilize sensor readings
}

// Function to control servo with delay logic for ultrasonic sensors
void controlServoWithDelay(int trigPin, int echoPin, Servo& servo, bool& isPersonDetected) {
  long distance = measureDistance(trigPin, echoPin);

  if (distance > 0 && distance <= detectionRange) {
    if (!isPersonDetected) { 
      servo.write(90); // Rotate to 90 degrees
      isPersonDetected = true;
    }
  } else {
    if (isPersonDetected) { 
      delay(delayTime); // Wait for 5 seconds
      servo.write(0); // Return servo to 0 degrees
      isPersonDetected = false;
    }
  }
}