#include <Wire.h>
#include <U8g2lib.h>
#include <DHT.h>

#define DHTPIN PA2       // DHT Data pin
#define DHTTYPE DHT22    // Sensor type
DHT dht(DHTPIN, DHTTYPE);

// Correct I2C pins for STM32 Bluepill
U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0, U8X8_PIN_NONE, PB6, PB7);

void setup() {
  Serial.begin(9600);
  dht.begin();
  Wire.begin();
  u8g2.begin();

  // Splash screen
  u8g2.clearBuffer();
  u8g2.setFont(u8g2_font_6x12_tr);
  u8g2.drawStr(0, 20, "DHT22 + OLED Test");
  u8g2.sendBuffer();
  delay(2000);
}

void loop() {
  float temp = dht.readTemperature();
  float hum = dht.readHumidity();

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

  Serial.print("Temp: ");
  Serial.print(temp);
  Serial.print(" *C, Humidity: ");
  Serial.print(hum);
  Serial.println(" %");

  // Display on OLED
  u8g2.clearBuffer();
  u8g2.setFont(u8g2_font_ncenB14_tr);
  u8g2.setCursor(0, 20);
  u8g2.print("T:");
  u8g2.print(temp, 1);
  u8g2.print("C");

  u8g2.setCursor(0, 50);
  u8g2.print("H:");
  u8g2.print(hum, 1);
  u8g2.print("%");
  u8g2.sendBuffer();

  delay(2000);
}