#include <Arduino.h>

// Pins for Segments a, b, c, d, e, f, g (A-G)
const int segmentPins[] = {2, 3, 4, 5, 6, 7, 8}; 

// Pins for Digit Selectors (14 digits)
// Mapping: 0-1: DD, 2-3: MM, 4-7: YYYY, 8-9: HH, 10-11: MM, 12-13: SS
//const int digitPins[] = {9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22};
const int digitPins[] = {9, 10, 11, 12, 13, 14, 15, A0, A1, A2, A3, A4, A5, 1};

// Segment patterns for numbers 0-9 (Common Anode assumed for Wokwi default)
const byte numTable[] = {
  0xC0, 0xF9, 0xA4, 0xB0, 0x99, 0x92, 0x82, 0xF8, 0x80, 0x90
};

int d=31, mo=12, y=2025, h=23, mi=59, s=40;
unsigned long lastTick = 0;

void setup() {
  for(int i=0; i<7; i++) pinMode(segmentPins[i], OUTPUT);
  for(int i=0; i<14; i++) {
    pinMode(digitPins[i], OUTPUT);
    digitalWrite(digitPins[i], LOW); // Turn off all digits
  }
}

void displayDigit(int digitIdx, int value) {
  // 1. Turn off all digits (Set all COM pins HIGH for Cathode)
  for(int i=0; i<14; i++) digitalWrite(digitPins[i], HIGH);

  // 2. Set segment pins (HIGH = ON for Common Cathode)
  // We use ~numTable to invert the bits because numTable was for Anode
  byte pattern = ~numTable[value]; 
  for(int i=0; i<7; i++) {
    digitalWrite(segmentPins[i], (pattern >> i) & 0x01);
  }

  // 3. Turn on current digit (Pull COM to LOW/GND)
  digitalWrite(digitPins[digitIdx], LOW);
  delayMicroseconds(500); 
}

void loop() {
  // --- Timing Logic ---
  if (millis() - lastTick >= 1000) {
    lastTick = millis();
    s++;
    if(s >= 60) { s=0; mi++; }
    if(mi >= 60) { mi=0; h++; }
    if(h >= 24) { h=0; d++; }
    // Note: Simple month rollover for demo
    if(d > 31) { d=1; mo++; }
    if(mo > 12) { mo=1; y++; }
  }

  // --- Display Multiplexing ---
  // Date (DD:MM:YYYY)
  displayDigit(0, d/10); 
  displayDigit(1, d%10);
  displayDigit(2, mo/10); 
  displayDigit(3, mo%10);
  displayDigit(4, y/1000); 
  displayDigit(5, (y/100)%10);
  displayDigit(6, (y/10)%10); 
  displayDigit(7, y%10);

  // Time (HH:MM:SS)
  displayDigit(8, h/10); 
  displayDigit(9, h%10);
  displayDigit(10, mi/10); 
  displayDigit(11, mi%10);
  displayDigit(12, s/10); 
  displayDigit(13, s%10);
}