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

#define SCREEN_WIDTH 128 
#define SCREEN_HEIGHT 64

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

RTC_DS1307 rtc;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  while(!Serial);

  Wire.begin();
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)){
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }
  display.clearDisplay(); // ล้างหน้าจอ
  display.setTextSize(1); // กำหนดขนาดตัวอักษร
  display.setTextColor(SSD1306_WHITE); // กำหนดสีตัวอักษร
  display.setCursor(0, 0); // กำหนดตำแหน่งเริ่มต้น
  display.println("Initializing...");
  display.display(); // อัปเดตหน้าจอ

  if (!rtc.begin()){
    Serial.println("Couldn't find RTC");
    display.clearDisplay();
    display.println("RTC not found");
    display.display();
    while(1);
  }

  if(rtc.isrunning()){
    Serial.println("RTC lost power , Setting time");
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }
  delay(1000);
}

void loop() {
  // put your main code here, to run repeatedly:
  DateTime now = rtc.now();
  // ล้างหน้าจอ OLED
  display.clearDisplay();

  // แสดงข้อความ "Current Time:"
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println("Current Time:");

  display.setTextSize(2);
  display.setCursor(0, 16);
  if(now.hour() < 10) display.print("0");
  display.print(now.hour());
  display.print(":");
  if(now.minute()< 10) display.print("0");
  display.print(now.minute());
  display.print(":");
  if(now.second() < 10 ) display.print("0");
  display.print(now.second());

  display.setTextSize(1);
  display.setCursor(0,48);
  display.print(now.day());
  display.print("/");
  display.print(now.month());
  display.print("/");
  display.print(now.year());

  display.display();

  delay(1000);
}