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

// LED pins (controlled by PIR sensors)
#define LED1 14
#define LED2 12
#define LED3 13

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

// Ultrasonic sensor pins (Trig and Echo)
#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

// LDR (Flame Sensor) pins for three rooms
#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);

// Wi-Fi credentials
const char* ssid = "Wokwi-GUEST";
const char* password = "";

// ThingSpeak API settings
const char* server = "http://api.thingspeak.com/update";
const char* apiKey = "MBVQCQWEFH3MISVV";

// Threshold for flame detection (adjust based on LDR readings)
const int flameThreshold = 800;

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

// Delay time (in ms) for returning servo to 0 degrees
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; // Convert duration to cm
  return distance;
}

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

  // Initialize Wi-Fi connection
  WiFi.begin(ssid, password);
  Serial.print("Connecting to Wi-Fi");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWi-Fi connected!");

  // 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();

  Serial.println("Setup complete");
}

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!");
  }

  int motion1 = digitalRead(PIR1);
  int motion2 = digitalRead(PIR2);
  int motion3 = digitalRead(PIR3);
  Serial.println(motion1);

  // 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);

  bool flameDetected = (ldr1Value < flameThreshold || ldr2Value < flameThreshold || ldr3Value < flameThreshold);

  if (flameDetected) {
    Serial.println("Flame detected!");
    digitalWrite(BUZZER, HIGH);
  } else {
    digitalWrite(BUZZER, LOW);
  }

  // Send data to ThingSpeak
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String url = String(server) + "?api_key=" + apiKey + 
                 "&field1=" + String(temperature) + 
                 "&field2=" + String(humidity) + 
                 "&field3=" + String(motion1) + 
                 "&field4=" + String(motion2) + 
                 "&field5=" + String(motion3) + 
                 "&field6=" + String(flameDetected);
    http.begin(url);
    int httpResponseCode = http.GET();
    if (httpResponseCode > 0) {
      Serial.println("Data sent to ThingSpeak");
    } else {
      Serial.println("Failed to send data to ThingSpeak");
    }
    http.end();
  }

  delay(2000); // Wait 2 seconds before sending the next data
}

// 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) { // If not already detected
      Serial.println("Person detected! Rotating servo to 90 degrees...");
      servo.write(90); // Rotate to 90 degrees
      isPersonDetected = true;
    }
  } else {
    if (isPersonDetected) { // If previously detected but now out of range
      Serial.println("Person moved out of range. Waiting 5 seconds...");
      delay(delayTime); // Wait for 5 seconds
      servo.write(0); // Return servo to 0 degrees
      Serial.println("Servo returned to 0 degrees.");
      isPersonDetected = false;
    }
  }
}