#include "DHT.h"
#define trigPin 12      // Trig pin of the ultrasonic sensor connected to Arduino pin 12
#define echoPin 13      // Echo pin of the ultrasonic sensor connected to Arduino pin 13
#define LDR_PIN 34    // LDR connected to GPIO34 (Analog)
#define PIR_PIN 23    // PIR connected to GPIO23 (Digital)
#define LED_PIN 22    // LED 1 connected to GPIO22 (Digital)
#define TEMP_LED_PIN 21  // LED 2 connected to GPIO21 (Digital)
#define COLD_LED_PIN 19   // LED 3 connected to GPIO19 (Digital)
#define DHT_PIN 4      // DHT22 sensor connected to GPIO4
#define LED4 16         // LED 4 connected to Arduino pin 11
#define DHTTYPE DHT22
DHT dht(DHT_PIN, DHTTYPE);

void setup() {
    Serial.begin(115200);
    pinMode(trigPin, OUTPUT);   // Set trigPin as an output
    pinMode(echoPin, INPUT);    // Set echoPin as an input
    pinMode(PIR_PIN, INPUT);    // Set PIR pin as input
    pinMode(LED_PIN, OUTPUT);    // Set LED 1 pin as output
    pinMode(TEMP_LED_PIN, OUTPUT);  // Set LED 2 pin as output
    pinMode(COLD_LED_PIN, OUTPUT);    // Set LED 3 pin as output
    pinMode(LED4, OUTPUT);
    dht.begin();                 // Initialize DHT sensor
    digitalWrite(LED_PIN, LOW);  // Turn OFF LED 1
    digitalWrite(TEMP_LED_PIN, LOW); // Turn OFF LED 2
    digitalWrite(COLD_LED_PIN, LOW);  // Turn OFF LED 3
    digitalWrite(LED4, LOW);
}

void loop() {
    long duration, distance;

    digitalWrite(trigPin, LOW); // Clear the trigger
    delayMicroseconds(2);         // Wait for 2 microseconds
    digitalWrite(trigPin, HIGH); // Set the trigger high
    delayMicroseconds(10);        // Keep it high for 10 microseconds
    digitalWrite(trigPin, LOW);  // Set the trigger low

    // Read the echo pin
    duration = pulseIn(echoPin, HIGH); // Read the incoming pulse
    distance = (duration / 2) * 0.0343; // Calculate the distance in cm, speed of sound = 
    int ldrValue = analogRead(LDR_PIN);   // Read LDR value
    int pirValue = digitalRead(PIR_PIN);   // Read PIR value
    float temperature = dht.readTemperature(); // Read temperature from DHT22

    Serial.print("LDR Value: ");
    Serial.print(ldrValue);
    Serial.print(" | PIR Value: ");
    Serial.print(pirValue);
    Serial.print(" | Temperature: ");
    Serial.println(temperature);
    Serial.print("Distance: ");
    Serial.print(distance);
    Serial.println(" cm");

    // Check the conditions for LED 1
    if (pirValue == HIGH && ldrValue < 200) {
        digitalWrite(LED_PIN, HIGH);  // Turn ON LED 1
    } else {
        digitalWrite(LED_PIN, LOW);   // Turn OFF LED 1
    }

    // Check the temperature condition for LED 2
    if (pirValue == HIGH && temperature >= 30.0) {
        digitalWrite(TEMP_LED_PIN, HIGH); // Turn ON LED 2
    } else {
        digitalWrite(TEMP_LED_PIN, LOW);  // Turn OFF LED 2
    }

    // Check conditions for LED 3
    if (pirValue == HIGH && temperature < 20.0) {
        digitalWrite(COLD_LED_PIN, HIGH); // Turn ON LED 3
    } else {
        digitalWrite(COLD_LED_PIN, LOW);   // Turn OFF LED 3
    }

    // Control LEDs based on distance
    if (distance < 200) {
        digitalWrite(LED4, HIGH); // Turn on the 4th LED if distance is less than 200 cm
    } else {
        digitalWrite(LED4, LOW);  // Turn off the 4th LED if distance is 200 cm or more
    }

    delay(100);   // Delay for stability and to prevent excessive readings
}