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

RTC_DS3231 rtc;

// Define the pins for the TM1637
const int CLK = D8; // Connect to CLK pin
const int DIO = D9; // Connect to DIO pin

// Segment mapping for numbers 0-9
const int segmentMapping[10][8] = {
    {HIGH, HIGH, HIGH, HIGH, HIGH, HIGH, LOW}, // 0
    {LOW, LOW, HIGH, LOW, LOW, LOW, LOW},       // 1
    {HIGH, HIGH, LOW, HIGH, HIGH, LOW, HIGH},  // 2
    {HIGH, HIGH, LOW, HIGH, LOW, LOW, HIGH},   // 3
    {LOW, HIGH, HIGH, LOW, LOW, HIGH, LOW},     // 4
    {HIGH, LOW, HIGH, HIGH, LOW, HIGH, HIGH},  // 5
    {HIGH, LOW, HIGH, HIGH, HIGH, HIGH, HIGH},  // 6
    {HIGH, HIGH, LOW, LOW, LOW, LOW, LOW},      // 7
    {HIGH, HIGH, HIGH, HIGH, HIGH, HIGH, HIGH}, // 8
    {HIGH, HIGH, HIGH, LOW, LOW, HIGH, HIGH}    // 9
};

void setup() {
    Serial.begin(9600);
    Wire.begin();
    
    rtc.begin();

    // Check if RTC is connected
    if (!rtc.begin()) {
        Serial.println("Couldn't find RTC");
        while (1);
    }

    // Set the time if it’s not already set
    if (rtc.lostPower()) {
        rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
    }

    pinMode(CLK, OUTPUT);
    pinMode(DIO, OUTPUT);
}

void loop() {
    DateTime now = rtc.now();
    int displayTime = now.hour() * 100 + now.minute(); // Format HHMM

    displayNumber(displayTime); // Display the formatted time

    delay(1000);
}

void displayNumber(int number) {
    int digits[4];
    digits[0] = number / 1000; // Thousands
    digits[1] = (number / 100) % 10; // Hundreds
    digits[2] = (number / 10) % 10; // Tens
    digits[3] = number % 10; // Units

    for (int i = 0; i < 4; i++) {
        showDigit(i, digits[i]);
        delay(5); // Short delay for multiplexing
    }
}

void showDigit(int position, int number) {
    // You would need to turn on the correct segments here
    // Activate the digit (this is pseudo-code for understanding)
    // In reality, you would send data through CLK and DIO to control the display
    // You can implement the segment activation logic here.
    // Use the segmentMapping array to set the pins accordingly.
}