/* StopWatch
 * Sketch is based on Paul Badger's StopWatch sketch,
 * http://playground.arduino.cc/Code/Stopwatch
 */

#include "Adafruit_LEDBackpack.h"
#include "Adafruit_GFX.h" 
#include <Wire.h>  
Adafruit_7segment matrix = Adafruit_7segment();     // for LED display 

#define ledPin  13                  // LED connected to digital pin 13
#define buttonPin 4                 // button on pin 4

int value = LOW;                    // previous value of the LED
int buttonState;                    // variable to store button state
int lastButtonState;                // variable to store last button state
int blinking;                       // condition for blinking - timer is timing
long interval = 50;                 // blink interval - change to suit
long previousMillis = 0;            // variable to store last time LED was updated
long startTime ;                    // start time for stop watch
long elapsedTime ;                  // elapsed time for stop watch
int fractional;                     // variable used to store fractional part of time
//long now;

void setup()
{
   Serial.begin(9600);
   pinMode(ledPin, OUTPUT);         // sets the digital pin as output
   pinMode(buttonPin, INPUT);       // not really necessary, pins default to INPUT anyway
   digitalWrite(buttonPin, HIGH);   // turn on pullup resistors. Wire button so that press shorts pin to ground.

  matrix.begin(0x70);               // 
  matrix.setBrightness(15);
//  matrix.writeDigitRaw(0,10101111);
//  matrix.writeDigitRaw(1,10101110);
//  matrix.writeDigitNum(3, 0);
//  matrix.writeDigitRaw(4,10110110);
//  matrix.writeDisplay();
//  delay(1000); 
  matrix.writeDigitRaw(0,0);
  matrix.writeDigitNum(1, 0); 
  matrix.writeDigitNum(3, 0); 
  matrix.writeDigitNum(4, 0); 
  matrix.writeDigitRaw(2, 0x02);
  matrix.writeDisplay(); 
}

void loop()
{
    // check for button press
   buttonState = digitalRead(buttonPin);                   // read the button state and store
  
   if (buttonState == LOW && lastButtonState == HIGH  &&  blinking == false){     // check for a high to low transition
      // if true then found a new button press while clock is not running - start the clock
      startTime = millis();                                // store the start time
      blinking = true;                                     // turn on blinking while timing
      delay(5);                                            // short delay to debounce switch
      lastButtonState = buttonState;                       // store buttonState in lastButtonState, to compare next time
     }

   else if (buttonState == LOW && lastButtonState == HIGH && blinking == true){     // check for a high to low transition
      // if true then found a new button press while clock is running - stop the clock and report

        elapsedTime =   millis() - startTime;              // store elapsed time
        blinking = false;                                  // turn off blinking, all done timing
        lastButtonState = buttonState;                     // store buttonState in lastButtonState, to compare next time
       // routine to report elapsed time
        Serial.print( (int)(elapsedTime / 1000L));         // divide by 1000 to convert to seconds - then cast to an int to print
        Serial.print(".");                                 // print decimal point

        // use modulo operator to get fractional part of time
       fractional = (int)(elapsedTime % 1000L);

       // pad in leading zeros - wouldn't it be nice if
       // Arduino language had a flag for this? :)
       if (fractional == 0)
          Serial.print("000");      // add three zero's
       else if (fractional < 10)    // if fractional < 10 the 0 is ignored giving a wrong time, so add the zeros
          Serial.print("00");       // add two zeros
       else if (fractional < 100)
          Serial.print("0");        // add one zero

       Serial.println(fractional);  // print fractional part of time to the serial port

   }

   else{
      lastButtonState = buttonState;                         // store buttonState in lastButtonState, to compare next time
   }

   // blink routine - blink the LED while timing
   // check to see if it's time to blink the LED; that is, the difference
   // between the current time and last time we blinked the LED is larger than
   // the interval at which we want to blink the LED.

   if ( (millis() - previousMillis > interval) ) {

      if (blinking == true){
       
      float now =  millis()-startTime; 
      String s  = String(trunc(now/1000));
      String ms = String(trunc((now/1000-trunc(now/1000))*100));
      
      if (now < 10000) {                  // If the time is less than 10 sec (10.000 msec)
       String s1 = s.substring(0, 1);     // ...we need the first digit only
       matrix.writeDigitRaw(0, 0);        // which we plot to the second place of 7-seg
       matrix.writeDigitNum(1, s1.toInt());        
      
       String s3 = ms.substring(0, 1);      // and ve plot the first and second place of miliseconds 
       String s4 = ms.substring(1, 2);
       matrix.writeDigitNum(3, s3.toInt()); // to the third...     
       matrix.writeDigitNum(4, s4.toInt()); // ...and fourth place of 7-seg.
       
       matrix.writeDisplay();
      
      }

      if (now > 10000) {                    // If the time is greater than 10 sec (10.000 msec) 
       String s1 = s.substring(0, 1);       // ...we need the first digit
       String s2 = s.substring(1, 2);       // ...and second digit
       matrix.writeDigitNum(0, s1.toInt()); // Which we plot to the first...       
       matrix.writeDigitNum(1, s2.toInt()); // ...and second digit of the 7-seg.       

       String s3 = ms.substring(0, 1);      // and ve plot the first and second place of miliseconds 
       String s4 = ms.substring(1, 2);
       matrix.writeDigitNum(3, s3.toInt()); // to the third...        
       matrix.writeDigitNum(4, s4.toInt()); // ...and fourth place of 7-seg.   
       
       matrix.writeDisplay();
      }
      
       if (now > 99950) {                    // If the time is greater than 99.95 sec (95.95 msec) 
          blinking = false;                  // stop the clock!
      }
      
         previousMillis = millis();                         // remember the last time we blinked the LED

         // if the LED is off turn it on and vice-versa.
         if (value == LOW)
            value = HIGH;
         else
            value = LOW;
         digitalWrite(ledPin, value);
      }
      else{
         digitalWrite(ledPin, LOW);                         // turn off LED when not blinking
      }
   }

}