/*
    A craptastic clock.
*/
#include "RTClib.h"

RTC_DS1307 rtc;

void NumberToSevenSeg(int n){
  digitalWrite(2,(n!=0)&&(n!=2)&&(n!=3)&&(n!=5)&&(n!=6)&&(n!=7)&&(n!=8)&&(n!=9));
  digitalWrite(3,(n!=0)&&(n!=1)&&(n!=2)&&(n!=3)&&(n!=4)&&(n!=7)&&(n!=8)&&(n!=9));
  digitalWrite(4,(n!=0)&&(n!=1)&&(n!=3)&&(n!=4)&&(n!=5)&&(n!=6)&&(n!=7)&&(n!=8)&&(n!=9));
  digitalWrite(5,(n!=0)&&(n!=2)&&(n!=3)&&(n!=5)&&(n!=6)&&(n!=8)&&(n!=9));
  digitalWrite(6,(n!=0)&&(n!=2)&&(n!=6)&&(n!=8));
  digitalWrite(7,(n!=0)&&(n!=4)&&(n!=5)&&(n!=6)&&(n!=8)&&(n!=9));
  digitalWrite(8,(n!=2)&&(n!=3)&&(n!=4)&&(n!=5)&&(n!=6)&&(n!=8)&&(n!=9));
}

void FourStageSevenSeg(String n){
 for(int q=10;q<=13;q++){
  for(int c=2;c<=8;c++){digitalWrite(c,HIGH);} // set character pins HIGH to clear
  char y = n.charAt(q-10);
  String x = String(y);
  digitalWrite(q,HIGH);         // set a select pin HIGH to select a character
  NumberToSevenSeg(x.toInt());  // write character to display
  digitalWrite(q,LOW);          // deselect the character
 }
}

void setup () {
  for(int i=2;i<=13;i++){pinMode(i,OUTPUT);digitalWrite(i,HIGH);}
  FourStageSevenSeg("0000");
  if (!rtc.begin()){abort();}
}

void loop () {
  DateTime now=rtc.now();
  String h = String(now.hour());  while(h.length()<2){h=("0"+h);}
  String m = String(now.minute());while(m.length()<2){m=("0"+m);}
  FourStageSevenSeg(h+m);delay(16);
}