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

//pins
const int buzzer = 4;
const int button = 2;

//OLED display
#define screen_width 128 //OLED display width in pixels
#define screen_height 64 //OLED display height in pixels

Adafruit_SSD1306 display(screen_width, screen_height); //creating the display object

void oled_display(bool clear_display,int text_size,int cursor_x, int cursor_y,char* string){
  if (clear_display){
    display.clearDisplay();
  }
  display.setTextSize(text_size);
  display.setTextColor(WHITE);
  display.setCursor(cursor_x, cursor_y);
  display.print(string);
  display.display();
}

char* string temperature;
const float BETA = 3950; // should match the Beta Coefficient of the thermistor
bool count = false;
int time = 0;

void setup() {
  pinMode(button, INPUT);
  pinMode(buzzer, OUTPUT);
  display.begin(SSD1306_SWITCHCAPVCC, 0x3c);
  oled_display(true, 2, 6,27, "Temperature");
  delay(2000);
}

void loop() {

  int analogValue = analogRead(A0);
  float celsius_temp = 1 / (log(1 / (1023. / analogValue - 1)) / BETA + 1.0 / 298.15) - 273.15;
  temperature = string(celsius_temp) + " ℃";

  oled_display(true, 2, 10,27, temperature);

  buttonState = digitalRead(button);

  if (counter == true){
    time += 6
  }
  
  if (buttonState == HIGH) {
    counter = true;
  }

  if (time == 120){
    tone(buzzer, 1000);
    delay(3000);
    noTone(buzzer);
  }

  delay(6000);
}