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

Adafruit_SSD1306 srituhobby = Adafruit_SSD1306(128, 64, &Wire);

#define sensor A0

int sX = 10;
int sY = 50;
int x = 10;
int Svalue;
int value;
int value1;
int pb = 3;
bool state = false;
int detik = 0;
int menit = 0;

long lastButtonPress = 0; // to store the last time the button was pressed
long timerStart = 0;      // to store the start time of the timer
bool timerRunning = false; // to indicate if the timer is running

void setup() {
  Serial.begin(9600);
  pinMode(pb, INPUT_PULLUP);
  srituhobby.begin(SSD1306_SWITCHCAPVCC, 0x3C);  // Address 0x3C for 128x64
  delay(1000);
  srituhobby.clearDisplay();
  srituhobby.drawLine(10, 10, 10, 50, WHITE); // Draw initial axes
  srituhobby.drawLine(10, 50, 120, 50, WHITE);
  srituhobby.display();
}

void loop() {
  // Read sensor and map values
  Svalue = analogRead(sensor);
  value1 = map(Svalue, 0, 1023, 2000, 5000);
  value = map(value1, 2000, 5000, 1, 40);
  int y = 50 - value;

  // Draw graph
  if (x > 128) {
    x = 10;
    sX = 10;
    srituhobby.clearDisplay();
    srituhobby.drawLine(10, 10, 10, 50, WHITE);
    srituhobby.drawLine(10, 50, 120, 50, WHITE);
  } else {
    srituhobby.drawLine(sX, sY, x, y, WHITE);
    sX = x;
    sY = y;
    x++;
  }

  // Timer logic
  if (!digitalRead(pb) && (millis() - lastButtonPress > 200)) {
    srituhobby.clearDisplay();
    srituhobby.drawLine(10, 10, 10, 50, WHITE);
    srituhobby.drawLine(10, 50, 120, 50, WHITE);
    x = 10;
    sX = 10;
    lastButtonPress = millis();
    if (!timerRunning) {
      timerRunning = true;
      timerStart = millis();
      menit = 44;
      detik = 0;
    }
  }

  if (timerRunning) {
    long elapsed = (millis() - timerStart) / 1000;
    detik = 60 - (elapsed % 60);
    menit = 44 - (elapsed / 60);

    if (menit < 0) {
      timerRunning = false;
      menit = 0;
      detik = 0;
    }
  }

  // Display timer with larger text and clear background
  srituhobby.fillRect(90, 0, 38, 16, BLACK); // Clear background for timer
  srituhobby.setTextSize(1); // Larger text size
  srituhobby.setTextColor(SSD1306_WHITE);
  srituhobby.setCursor(90, 0);
  srituhobby.print(menit);
  srituhobby.print(":");
  if (detik < 10) {
    srituhobby.print("0");
  }
  srituhobby.print(detik);

  // Display everything
  srituhobby.display();
  delay(50); // Small delay to slow down the drawing speed
}