//
// https://forum.arduino.cc/t/funktion-millis-to-uhrzeit/1350414/35
//
#include <TM1637Display.h>
#include <Streaming.h>   // https://github.com/janelia-arduino/Streaming
Print& cout {Serial};

// Global constants
namespace gc {
constexpr uint8_t pin_clk {2};
constexpr uint8_t pin_dio {3};
}   // namespace gc

// Anleihe von @Combie
using Millis = decltype(millis());   // mostly 32Bit, sometimes 64Bit
constexpr Millis operator"" _ms(unsigned long long int t) { return t; }

constexpr Millis operator"" _seconds(unsigned long long int t) { return t * 1000_ms; }
constexpr Millis operator"" _minutes(unsigned long long int t) { return t * 60_seconds; }
constexpr Millis operator"" _hours(unsigned long long int t) { return t * 60_minutes; }
constexpr Millis operator"" _days(unsigned long long int t) { return t * 24_hours; }

constexpr Millis operator"" _second(unsigned long long int t) { return t * 1000_ms; }
constexpr Millis operator"" _minute(unsigned long long int t) { return t * 60_seconds; }
constexpr Millis operator"" _hour(unsigned long long int t) { return t * 60_minutes; }
constexpr Millis operator"" _day(unsigned long long int t) { return t * 24_hours; }

class Timer
{
  public:
    void start() {timeStamp = millis();}
    bool operator() (const unsigned long duration) const {
      return (millis() - timeStamp >= duration) ?  true : false;
    }
  private:
    unsigned long timeStamp {0};
};


class MillisToTime {
public:
  void time(Millis tMillis) {
    vDays = tMillis / 1_day;
    tMillis %= 1_days;
    vHours = tMillis / 1_hour;
    tMillis %= 1_hours;
    vMinutes = tMillis / 1_minute;
    tMillis %= 1_minutes;
    vSeconds = tMillis / 1_second;
  }

  uint8_t seconds() const { return vSeconds; }
  uint8_t minutes() const { return vMinutes; }
  uint8_t hours() const { return vHours; }
  uint8_t days() const { return vDays; }

private:
  uint8_t vSeconds {0};
  uint8_t vMinutes {0};
  uint8_t vHours {0};
  uint8_t vDays {0};
};

Timer interval;
MillisToTime mtt;
TM1637Display display(gc::pin_clk, gc::pin_dio);

void setup() { 
  Serial.begin(115200); 
  display.setBrightness(0x0f);
}

void loop() {
  static char tBuffer[12] {"00:00:00:00"};
  static uint8_t dot_flag {0x40}; 

  if (interval(1_second)) {
    interval.start();
    mtt.time(millis());
    
    snprintf(tBuffer, sizeof(tBuffer), "%02d:%02d:%02d:%02d", mtt.days(), mtt.hours(), mtt.minutes(), mtt.seconds());
    cout << tBuffer << endl;
    // cout << _FMT("%:%:%:%", _WIDTHZ(mtt.days(), 2), _WIDTHZ(mtt.hours(), 2), _WIDTHZ(mtt.minutes(), 2),
    // _WIDTHZ(mtt.seconds(), 2))
    // << endl;

    unsigned int tmp_time = mtt.minutes() * 100 + mtt.seconds();
    display.showNumberDecEx(tmp_time, dot_flag, true, 4); // 0x64 : dots on, leading zeros, four digits
    dot_flag ^= 0x40;
  }
}