class LED{
  public:
    LED(){};
    ~LED(){};

    void begin(int thePin){
      pin = thePin;  // Save off the pin number
      pinMode(pin, OUTPUT);
    };
    void on(){
      digitalWrite(pin, LOW);
    };
    void off(){
      digitalWrite(pin, HIGH);
    };
  private:
    int pin;
};

class SevenSegment{
  public:
    SevenSegment(){};
    ~SevenSegment(){};

    void begin(int a, int b, int c, int d, int e, int f, int g, int dp ){
      myLeds[0].begin(dp);
      myLeds[1].begin(g);
      myLeds[2].begin(f);
      myLeds[3].begin(e);
      myLeds[4].begin(d);
      myLeds[5].begin(c);
      myLeds[6].begin(b);
      myLeds[7].begin(a);
    };

    void write(int digit){
      for( int i = 0; i < 8; i++ ){
        if ( bitRead(lut[digit], i) == 1 ){
          myLeds[i].on();
        } else {
          myLeds[i].off();
        }
      }
    };
  private:
    LED myLeds[8];
                    //    abcdefgp
    uint8_t lut[10] = { 0b11111100,  // 0
                        0b01100000,  // 1
                        0b11011010,  // 2
                        0b11110010,  // 3
                        0b01100110,  // 4
                        0b10110110,  // 5
                        0b10111110,  // 6
                        0b11100000,  // 7
                        0b11111110,  // 8
                        0b11100110}; // 9
};

class FourDigitDisplay{
  public:
    FourDigitDisplay(){};
    ~FourDigitDisplay(){};

    void begin(int a, int b, int c, int d, int e, int f, int g, int dp, int d1, int d2, int d3, int d4 ){
      // Save off the dig pins
      myDigits[0] = d4;
      myDigits[1] = d3;
      myDigits[2] = d2;
      myDigits[3] = d1;
      for ( int i=0; i < 4; i++){
        pinMode(myDigits[i], OUTPUT);     // Make the dig pin an output
        digitalWrite(myDigits[i], LOW);   // Set the output to zero volts to turn off the digit display
        mySevenSegmentDisplays[i].begin(a, b, c, d, e, f, g, dp);
      }
    }

    void write( ){
      int digits[4] = {1, 2, 3, 4};

      // Show all four digits one at a time -- just once
      for ( int i = 0; i < 4; i++ ){
        mySevenSegmentDisplays[i].write( digits[i] );   // Set segments a-g and dp
        digitalWrite(myDigits[i], HIGH);                // Turn the digit on
        delay(500);                                     // Wait a bit
        digitalWrite(myDigits[i], LOW);                 // Turn the digit off
      }
    }

  private:
    SevenSegment mySevenSegmentDisplays[4];
    int myDigits[4];
};

FourDigitDisplay myFourDigitDisplay;

void setup() {
  // put your setup code here, to run once:
  myFourDigitDisplay.begin(9,8,7,6,5,4,3,2, 13, 12, 11, 10);
}

void loop() {
  // put your main code here, to run repeatedly:
  myFourDigitDisplay.write();
}