/*
 Thank you to SparkFun for the majority of this code, which is publicly available from their website

 Arduino pin 6 -> CLK (Green on the 6-pin cable)
 5 -> LAT (Blue)
 7 -> SER on the IN side (Yellow)
 5V -> 5V (Orange)
 Power Arduino with 12V and connect to Vin -> 12V (Red)
 GND -> GND (Black)



*/

//GPIO declarations
//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
byte segmentClock = 6;
byte segmentLatch = 5;
byte segmentData = 7;
const byte interruptPin=2; //toggle switch is on pin D2

int number = 0;
unsigned long timeAtPrevLap = 100000; //assume an initial time (will be soon overwritten by millis command, in the ISR
unsigned long timeAtThisLap = 120000; //assume an initial time for the second lap (will be soon overwritten by millis command, in the ISR
//int timeForTen=100000; //the time taken to do 10 laps
unsigned long timeForLast=1000;// millseconds taken for last lap
int lapSpeed=8888;
int lapCounter=0; //start with no laps
int lapDistance = 40; //40m circumference
boolean decimalPoint=0;
//int aveSpeed = 10; //assume a speed of 10mph initially

//-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

void setup()
{
  Serial.begin(9600);
  Serial.println("Large Digit Driver Example");

  pinMode(segmentClock, OUTPUT);
  pinMode(segmentData, OUTPUT);
  pinMode(segmentLatch, OUTPUT);
  pinMode(interruptPin, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(interruptPin), timeSince, RISING);

  digitalWrite(segmentClock, LOW);
  digitalWrite(segmentData, LOW);
  digitalWrite(segmentLatch, LOW);
  
}

void timeSince(){
  //timeAtThisLap=millis();
  if((millis()-timeAtPrevLap)<400){
    return;  
  }             //this is to make sure only one pulse per lap is counted
  else{
  timeForLast=millis()-timeAtPrevLap;

  lapCounter=lapCounter+1;
  timeAtPrevLap=millis();
  }
}

void loop()
{
  showNumber(lapSpeed); //Test pattern

  lapSpeed=(((lapDistance/1.625*3600)/(timeForLast))*100);

  if(lapSpeed>9999){
    lapSpeed=lapSpeed/10;
    decimalPoint=1;
  }
  else{
    decimalPoint=0;
  }
//   if(lapSpeed > 1990)
//   {
//    lapSpeed=8888;
//    }
 //   else{}
//  Serial.print(lapCounter);
  Serial.print("\t interval");
   Serial.print(timeForLast);
   Serial.print("time at previous ");
   Serial.print(timeAtPrevLap);
   Serial.print("lap number ");
   Serial.print(lapCounter);  
      Serial.print("decimal point showing ");
   Serial.print(decimalPoint);   
   Serial.print("speed ");
  Serial.println(lapSpeed); //For debugging




  

  delay(500);
}

//Takes a number and displays 4 numbers. Displays absolute value (no negatives)
void showNumber(float lapSpeed)
{
  int number = (lapSpeed); //Remove negative signs and any decimals

  //Serial.print("number: ");
  //Serial.println(number);

 // for (byte x = 0 ; x < 4 ; x++)
//  {
//    int remainder = number % 10;

//    postNumber(remainder, true);
//postNumber(remainder, false);
//    number /= 10;
    
//  }

 if(decimalPoint==0){   //sub 100mph laps
  int remainder = number % 10;
  postNumber(remainder, false);
  number/=10;

    remainder = number % 10;
  postNumber(remainder, false);
  number/=10;

    remainder = number % 10;
  postNumber(remainder, true);
  number/=10;

     remainder = number % 10;
  postNumber(remainder, false);
  number/=10;

  //Latch the current segment data
  digitalWrite(segmentLatch, LOW);
  digitalWrite(segmentLatch, HIGH); //Register moves storage register on the rising edge of RCK
}
else{  int remainder = number % 10;       //more than 100mph, so move decimal point
  postNumber(remainder, false);
  number/=10;

    remainder = number % 10;
  postNumber(remainder, true);
  number/=10;

    remainder = number % 10;
  postNumber(remainder, false);
  number/=10;

     remainder = number % 10;
  postNumber(remainder, false);
  number/=10;

  //Latch the current segment data
  digitalWrite(segmentLatch, LOW);
  digitalWrite(segmentLatch, HIGH); //Register moves storage register on the rising edge of RCK
}
}

//Given a number, or '-', shifts it out to the display
void postNumber(byte number, boolean decimal)
{
  //    -  A
  //   / / F/B
  //    -  G
  //   / / E/C
  //    -. D/DP

#define a  1<<0
#define b  1<<6
#define c  1<<5
#define d  1<<4
#define e  1<<3
#define f  1<<1
#define g  1<<2
#define dp 1<<7

  byte segments;

  switch (number)
  {
    case 1: segments = b | c; break;
    case 2: segments = a | b | d | e | g; break;
    case 3: segments = a | b | c | d | g; break;
    case 4: segments = f | g | b | c; break;
    case 5: segments = a | f | g | c | d; break;
    case 6: segments = a | f | g | e | c | d; break;
    case 7: segments = a | b | c; break;
    case 8: segments = a | b | c | d | e | f | g; break;
    case 9: segments = a | b | c | d | f | g; break;
    case 0: segments = a | b | c | d | e | f; break;
    case ' ': segments = 0; break;
    case 'c': segments = g | e | d; break;
    case '-': segments = g; break;
  }

  if (decimal) segments |= dp;

  //Clock these bits out to the drivers
  for (byte x = 0 ; x < 8 ; x++)
  {
    digitalWrite(segmentClock, LOW);
    digitalWrite(segmentData, segments & 1 << (7 - x));
  //  digitalWrite(segmentData, 1<<7);

    digitalWrite(segmentClock, HIGH); //Data transfers to the register on the rising edge of SRCK
    
  }

  
}