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

#define SCREEN_WIDTH 128 
#define SCREEN_HEIGHT 64 

const int buttonPin1 = 18;  
const int buttonPin2 = 19; 

int buttonState1 = 0;         
int buttonState2 = 0; 
int lastButtonState1 = 0;
int lastButtonState2 = 0; 
unsigned long lastDebounceTime1 = 0; 
unsigned long lastDebounceTime2 = 0; 
const unsigned long debounceDelay = 50;

int counter = 0;
unsigned long previousMillis = 0; 
const long interval = 10;

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

void setup() {
  Serial.begin(115200);
  pinMode(buttonPin1, INPUT_PULLUP);
  pinMode(buttonPin2, INPUT_PULLUP);
  
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  delay(2000);
  display.clearDisplay();
  display.setTextColor(WHITE);
}

void loop() {
  display.clearDisplay();
  unsigned long currentMillis = millis();
  
  int reading1 = digitalRead(buttonPin1);
  int reading2 = digitalRead(buttonPin2);

  if (reading1 != lastButtonState1) {
    lastDebounceTime1 = millis();
  }
  if (reading2 != lastButtonState2) {
    lastDebounceTime2 = millis();
  }

  if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;
    if ((millis() - lastDebounceTime1) > debounceDelay) {
      if (reading1 != buttonState1) {
        buttonState1 = reading1;
        if (buttonState1 == LOW) {
         counter++;
        }
      }
    }
    if ((millis() - lastDebounceTime2) > debounceDelay) {
      if (reading2 != buttonState2) {
        buttonState2 = reading2;
        if (buttonState2 == LOW) {
          counter--;
        }
      }
    }

    lastButtonState1 = reading1;
    lastButtonState2 = reading2;

    if (buttonState1 == LOW && buttonState2 == LOW) {
      counter = 0;
    }
  }
  display.setTextSize(5);
  display.setCursor(0,14);
  display.print(counter);
  display.display(); 
}