#include <DHT.h>

#define DHTPIN 21
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

const int trigPin = 17;
const int echoPin = 16;
const int buzzerPin = 12;
const int DISTANCE_THRESHOLD = 20; // Adjust this threshold as needed

long duration;
float distanceCm;
float distanceInch;

void setup() {
  Serial.begin(9600);
  Serial.println(F("DHT22 and Ultrasonic Buzzer Example"));

  dht.begin();

  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzerPin, OUTPUT);

  // Initialize LEDC
  ledcSetup(0, 5000, 8); // LEDC channel 0, 5000 Hz, 8-bit resolution
  ledcAttachPin(buzzerPin, 0); // Attach buzzerPin to channel 0
}

void loop() {
  delay(2000);

  float h = dht.readHumidity();
  float t = dht.readTemperature();
  float f = dht.readTemperature(true);

  if (isnan(h) || isnan(t) || isnan(f)) {
    Serial.println(F("Failed to read from DHT sensor!"));
    return;
  }

  float hif = dht.computeHeatIndex(f, h);
  float hic = dht.computeHeatIndex(t, h, false);

  Serial.print(F("Humidity: "));
  Serial.print(h);
  Serial.print(F("% Temperature: "));
  Serial.print(t);
  Serial.print(F("°C "));
  Serial.print(F("°F Heat Index: "));
  Serial.print(hic);
  Serial.print(F("°C "));
  Serial.print(hif);
  Serial.println(F("°F"));

  // Ultrasonic
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  duration = pulseIn(echoPin, HIGH);

  distanceCm = duration * 0.034 / 2; // Speed of sound is 0.034 cm/microsecond
  distanceInch = distanceCm * 0.393701; // Convert distance to inches

  Serial.print("Distance (cm):");
  Serial.println(distanceCm);
  Serial.print("Distance (inch):");
  Serial.println(distanceInch);

  // Buzzer control based on distance
  if (distanceCm < DISTANCE_THRESHOLD) {
    ledcWrite(0, 128); // Activate the buzzer at 50% duty cycle
  } else {
    ledcWrite(0, 0); // Deactivate the buzzer
  }
}