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

#define SCREEN_WIDTH 128           
#define SCREEN_HEIGHT 64           

#define DHT22_PIN 13               

Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

DHT dht22(DHT22_PIN, DHT22);
String displayString;              

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

  if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("Error Display"));  
    while (true);  
  }
  delay(2000);  
  oled.clearDisplay();  

  oled.setTextSize(2);              
  oled.setTextColor(WHITE);          

  dht22.begin();   
  displayString.reserve(10);
}

void loop() {
  float humi = dht22.readHumidity();

  float tempC = dht22.readTemperature();

  if (isnan(humi) || isnan(tempC)) {
    displayString = "Error"; 
  } else {
    displayString = String(tempC, 1); 
    displayString += " C ";           
    displayString += String(humi, 1); 
    displayString += " %";            
  }

  Serial.println(displayString);

  oled.clearDisplay();                 
  oledDisplayCenter(displayString);    
  oled.display();                      

  delay(2000);  
}

void oledDisplayCenter(String text) {
  int16_t x1, y1;
  uint16_t width, height;

  oled.getTextBounds(text, 0, 0, &x1, &y1, &width, &height);

  int16_t x = (SCREEN_WIDTH - width) / 2;

  oled.setCursor(x, 25); 


  oled.print(text);
}