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

// ---------------- OLED Config ----------------
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// ---------------- DHT22 Config ----------------
#define DHTPIN 4        // ESP32 GPIO pin connected to DHT22 data pin
#define DHTTYPE DHT22   // DHT 22 (AM2302)
DHT dht(DHTPIN, DHTTYPE);

// ---------------- Setup ----------------
void setup() {
  Serial.begin(115200);

  // Initialize OLED
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("SSD1306 allocation failed");
    for (;;); // Don't proceed, loop forever
  }
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(10, 25);
  display.println("Initializing...");
  display.display();

  // Initialize DHT22
  dht.begin();
  delay(2000);
}

// ---------------- Loop ----------------
void loop() {
  // Read temperature and humidity
  float h = dht.readHumidity();
  float t = dht.readTemperature(); // Celsius
  float f = dht.readTemperature(true); // Fahrenheit

  // Check if any reads failed
  if (isnan(h) || isnan(t) || isnan(f)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  // Print to Serial Monitor
  Serial.print("Humidity: ");
  Serial.print(h);
  Serial.print("%  Temperature: ");
  Serial.print(t);
  Serial.println("°C");

  // Print to OLED
  display.clearDisplay();
  display.setTextSize(2);
  display.setCursor(0, 0);
  display.print("Temp:");
  display.setCursor(60, 0);
  display.print(t, 1);
  display.print("C");

  display.setTextSize(2);
  display.setCursor(0, 30);
  display.print("Hum:");
  display.setCursor(60, 30);
  display.print(h, 1);
  display.print("%");

  display.display();

  delay(2000); // update every 2 sec
}