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

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define OLED_ADDR 0x3C

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

#define DHTPIN 14
#define DHTTYPE DHT22

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200);
  Wire.begin(21, 22);
  dht.begin();

  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    Serial.println("SSD1306 allocation failed");
    while (true);
  }

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 0);
  display.println("ESP32 + DHT22");
  display.println("Initializing...");
  display.display();

  delay(2000);
}

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

  if (isnan(humidity) || isnan(temperature)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print(" C  |  Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

  display.clearDisplay();
  display.setCursor(0, 0);
  display.setTextSize(1);
  display.println("DHT22 Readings");

  display.setTextSize(2);
  display.setCursor(0, 18);
  display.print(temperature);
  display.println(" C");

  display.setCursor(0, 42);
  display.print(humidity);
  display.println(" %");

  display.display();
  delay(2000);
}