#include <U8g2lib.h>

// Pin definitions
#define BUTTON_PIN 2

// Display initialization
U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0);

// Fonts
const uint8_t* GOOD_FONT = u8g2_font_VCR_OSD_mr;
const uint8_t* STOPWATCH_FONT = u8g2_font_inb30_mf;

// Debounce parameters
const uint16_t DEBOUNCE_DELAY = 50;
const uint8_t DEBOUNCE_THRESHOLD = 3;

// Stopwatch state
volatile bool stopwatchRunning = false;
volatile uint32_t startTime = 0;
volatile uint32_t stopTime = 0;
volatile float elapsedTime = 0.0f;

// Button debounce variables
volatile uint8_t debounceCounter = 0;
volatile bool buttonPressed = false;
volatile bool buttonReleased = false;

void setup() {
  // Initialize button pin
  pinMode(BUTTON_PIN, INPUT_PULLUP);

  // Initialize display
  u8g2.begin();
  u8g2.setFont(GOOD_FONT);
  u8g2.clearBuffer();
  u8g2.drawStr(0, 30, "Good");
  u8g2.drawStr(0, 60, "Curling!");
  u8g2.sendBuffer();
}

void loop() {
  // Handle button debounce
  if (digitalRead(BUTTON_PIN) == LOW) {
    if (++debounceCounter >= DEBOUNCE_THRESHOLD) {
      if (!buttonPressed) {
        buttonPressed = true;
        buttonReleased = false;
      }
      debounceCounter = 0;
    }
  } else {
    if (++debounceCounter >= DEBOUNCE_THRESHOLD) {
      if (buttonPressed) {
        buttonPressed = false;
        buttonReleased = true;
      }
      debounceCounter = 0;
    }
  }

  // Handle button press
  if (buttonReleased) {
    buttonReleased = false;

    if (!stopwatchRunning) {
      // Start stopwatch
      startTime = millis();
      stopwatchRunning = true;
      elapsedTime = 0.0f;

      // Display stopwatch
      u8g2.setFont(STOPWATCH_FONT);
      u8g2.clearBuffer();
      u8g2.setCursor(0, 40);
      u8g2.print("0.000");
      u8g2.sendBuffer();
    } else {
      // Stop stopwatch
      stopTime = millis();
      stopwatchRunning = false;
      elapsedTime += (stopTime - startTime) / 1000.0f;

      // Display elapsed time
      u8g2.clearBuffer();
     // u8g2.setCursor(0, 10);
     // u8g2.print("Elapsed time:");
      u8g2.setCursor(0, 40);
      u8g2.print(elapsedTime, 3);
      u8g2.sendBuffer();
    }
  }

  // Update stopwatch
  if (stopwatchRunning) {
    // Calculate elapsed time
    elapsedTime += (millis() - startTime) / 1000.0f;
    startTime = millis();

    // Display elapsed time
    u8g2.clearBuffer();
  //  u8g2.setCursor(0, 10);
  //  u8g2.print("Elapsed time:");
    u8g2.setCursor(0, 40);
    u8g2.print(elapsedTime, 3);
    u8g2.sendBuffer();
  }
}