#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <DHT.h>

// OLED setup
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET    -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// DHT22 setup
#define DHTPIN 2       // Pin connected to DHT22 DATA pin
#define DHTTYPE DHT22  // DHT22 sensor type
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);

  // Initialize OLED
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed!"));
    for (;;);
  }
  display.clearDisplay();
  display.display();

  // Initialize DHT sensor
  dht.begin();
  Serial.println(F("DHT22 Initialized."));
}

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

  if (isnan(humidity) || isnan(temperature)) {
    Serial.println(F("DHT22 read failed!"));
    display.clearDisplay();
    display.setTextSize(1);
    display.setCursor(0, 0);
    display.println(F("Sensor Error!"));
    display.display();
    delay(2000);
    return;
  }

  // Print readings to Serial
  Serial.print(F("Temp: "));
  Serial.print(temperature);
  Serial.println(F("°C"));
  Serial.print(F("Humidity: "));
  Serial.print(humidity);
  Serial.println(F("%"));

  // Display readings on OLED
  display.clearDisplay();
  display.setTextSize(1);
  display.setCursor(0, 0);
  display.println(F("Temp & Humidity:"));
  display.setTextSize(2);
  display.setCursor(0, 16);
  display.print(F("Temp: "));
  display.print(temperature);
  display.println(F("C"));
  display.setCursor(0, 40);
  display.print(F("Hum: "));
  display.print(humidity);
  display.println(F("%"));
  display.display();

  delay(2000);
}