// segment macros
#define A 5
#define B 8
#define C A3
#define D A1
#define E A0
#define F 6
#define G A4
#define DP A2
// common anodes macros
#define GND1 7
#define GND2 9
#define GND3 10
#define GND4 A5

#define DOWN 0
#define UP 1
#define BUZZER 11


int minutes = 0;
int seconds = 0;
volatile boolean TurnUpDetected; //rotary encoder
volatile boolean TurnDownDetected;
unsigned long Watch, _micro;
unsigned int Clock = 0, R_clock;
boolean Reset = false, Stop = true, Paused = false, _type;
volatile boolean timeFlag = false;
unsigned long time;
int timer=0;
boolean timerStart=false; 
int i=0;
// functions to display digits

void setup()
{
  pinMode(2, INPUT_PULLUP);
  pinMode(4, INPUT_PULLUP);
  pinMode(3, INPUT);//button
  attachInterrupt(digitalPinToInterrupt(2), setState, FALLING);
  pinMode(A, OUTPUT);
  pinMode(B, OUTPUT);
  pinMode(C, OUTPUT);
  pinMode(D, OUTPUT);
  pinMode(E, OUTPUT);
  pinMode(F, OUTPUT);
  pinMode(G, OUTPUT);
  pinMode(DP, OUTPUT);
  pinMode(BUZZER, OUTPUT);
  pinMode(GND1, OUTPUT);
  pinMode(GND2, OUTPUT);
  pinMode(GND3, OUTPUT);
  pinMode(GND4, OUTPUT);
  digitalWrite(DP, HIGH); 
  Serial.begin(9600);
}

void digit0 () 
{
  digitalWrite(A, LOW);
  digitalWrite(B, LOW);
  digitalWrite(C, LOW);
  digitalWrite(D, LOW);
  digitalWrite(E, LOW);
  digitalWrite(F, LOW);
  digitalWrite(G, HIGH);
}

void digit1 () 
{
  digitalWrite(A,HIGH);
  digitalWrite(B, LOW);
  digitalWrite(C, LOW);
  digitalWrite(D, HIGH);
  digitalWrite(E, HIGH);
  digitalWrite(F, HIGH);
  digitalWrite(G, HIGH);
}

void digit2 () 
{
  digitalWrite(A,LOW);
  digitalWrite(B, LOW);
  digitalWrite(C, HIGH);
  digitalWrite(D, LOW);
  digitalWrite(E, LOW);
  digitalWrite(F, HIGH);
  digitalWrite(G, LOW);
};

void digit3 () 
{
  digitalWrite(A,LOW);
  digitalWrite(B, LOW);
  digitalWrite(C, LOW);
  digitalWrite(D, LOW);
  digitalWrite(E, HIGH);
  digitalWrite(F, HIGH);
  digitalWrite(G, LOW);
}

void digit4 () 
{
  digitalWrite(A,HIGH);
  digitalWrite(B, LOW);
  digitalWrite(C, LOW);
  digitalWrite(D, HIGH);
  digitalWrite(E, HIGH);
  digitalWrite(F, LOW);
  digitalWrite(G, LOW);
}

void digit5 () 
{
  digitalWrite(A,LOW);
  digitalWrite(B, HIGH);
  digitalWrite(C, LOW);
  digitalWrite(D, LOW);
  digitalWrite(E, HIGH);
  digitalWrite(F, LOW);
  digitalWrite(G, LOW);
}

void digit6 () 
{
  digitalWrite(A,LOW);
  digitalWrite(B, HIGH);
  digitalWrite(C, LOW);
  digitalWrite(D, LOW);
  digitalWrite(E, LOW);
  digitalWrite(F, LOW);
  digitalWrite(G, LOW);
}

void digit7 () 
{
  digitalWrite(A,LOW);
  digitalWrite(B, LOW);
  digitalWrite(C, LOW);
  digitalWrite(D, HIGH);
  digitalWrite(E, HIGH);
  digitalWrite(F, HIGH);
  digitalWrite(G, HIGH);
}

void digit8 () 
{
  digitalWrite(A, LOW);
  digitalWrite(B, LOW);
  digitalWrite(C, LOW);
  digitalWrite(D, LOW);
  digitalWrite(E, LOW);
  digitalWrite(F, LOW);
  digitalWrite(G, LOW);
}

void digit9 () 
{
  digitalWrite(A, LOW);
  digitalWrite(B, LOW);
  digitalWrite(C, LOW);
  digitalWrite(D, LOW);
  digitalWrite(E, HIGH);
  digitalWrite(F, LOW);
  digitalWrite(G, LOW);
}


void showdigit (int digit)
{

 switch (digit) 
 {
   case 0:
   digit0 ();
   break;
  
   case 1:
   digit1 ();
   break;
  
   case 2:
   digit2 ();
   break;
  
   case 3:
   digit3 ();
   break;
  
   case 4:
   digit4 ();
   break;
  
   case 5:
   digit5 ();
   break;
  
   case 6:
   digit6 ();
   break;
  
   case 7:
   digit7 ();
   break;
  
   case 8:
   digit8 ();
   break;
  
   case 9:
   digit9 ();
   break;
   
   default:

 break;

 }; 

}

// showing 4 digits
void showdigits (int number)
{
  // e.g. we have "1234"
  showdigit(number/1000);  // segments are set to display "1"
  digitalWrite(GND1, HIGH); // first digit on,
  digitalWrite(GND2, LOW); // other off
  digitalWrite(GND3, LOW);
  digitalWrite(GND4, LOW);
  digitalWrite(DP, HIGH); 
  
  delay (1);
  
  number = number%1000;  // remainder of 1234/1000 is 234
  digitalWrite(GND1, LOW); // first digit is off
   showdigit(number/100); //// segments are set to display "2"
  digitalWrite(GND2, HIGH); // second digit is on
  digitalWrite(DP, LOW); 
   delay (1); // and so on....
  
  number =number%100;    
  digitalWrite(GND2, LOW);
  showdigit(number/10);
  digitalWrite(GND3, HIGH);
  digitalWrite(DP, HIGH); 
  delay (1);
  
  number =number%10; 
  digitalWrite(GND3, LOW);
  showdigit(number); 
  digitalWrite(GND4, HIGH);
  digitalWrite(DP, HIGH); 
  delay (1);
}; 

void loop ()
{ 
  if(timerStart)
  {
    CountUpDownTimer(DOWN);
    timer++;
    showdigits(i);
    if (timer==10) 
        {
         timer = 0;
        }
  }
  if (TimeHasChanged() && timerStart)
  {
    int screenMinutes = ShowMinutes();
    int screenSeconds = ShowSeconds();
    i=(screenMinutes*100)+screenSeconds;
    if(Clock==0)
    {
      playAlarm();
      timerStart=false;
    }
  }
  if(!timerStart)
  {
    //Serial.println(minutes);
    showCurrentTime();
    if(TurnDownDetected)
    {
         TurnDownDetected = false;
         if(seconds>0&&seconds<3600)
         seconds=seconds-30;
         if(seconds>=3600)
         seconds=seconds-60;
         SetTimer(0,0,seconds);
    }
    if(TurnUpDetected)
    { 
        TurnUpDetected = false;
        if(seconds>=0&&seconds<3600)
        seconds=seconds+30;
        if(seconds>=3600)
        seconds=seconds+60;
        SetTimer(0,0,seconds);        
    }
    if (digitalRead(3)==LOW && Clock!=0)
    {
      timerStart = true;
      time = micros();
      StartTimer();
    }
  }
}

void showCurrentTime() 
{
  showdigits(i);
  int screenMinutes = ShowMinutes();
  int screenSeconds = ShowSeconds();
  int screenHours = ShowHours();
  if(screenMinutes<60)
  {
    i= (screenMinutes*100)+screenSeconds;
  }
  if(screenMinutes>=60)
  {
    i=(screenHours*100)+screenMinutes%60;
  }
  if (timer==10) 
  {
    timer = 0;
  }
}
  
void setState() //encoder
{
  if(digitalRead(4))
  {
    TurnDownDetected = true;
  }
  else
  {
    TurnUpDetected = true;
  } 
}

void playAlarm() //
{
  for(int i=0;i<12;i++)
  {
  tone(11, 4000); //4kHz pwm sequention
  delay(100);
  noTone(11);
  delay(100);
  tone(11, 4001);
  delay(100);
  noTone(11);
  delay(700);
  }
}

boolean CountUpDownTimer(boolean Type)
{
  _type = Type;
  static unsigned long duration = 1000000; // 1 second
  timeFlag = false;

  if (!Stop && !Paused) // if not Stopped or Paused, run timer
  {
    // check the time difference and see if 1 second has elapsed
    if ((_micro = micros()) - time > duration ) 
    {
      _type == UP? Clock++ : Clock--;
      timeFlag = true;

      if (_type == DOWN && Clock == 0) // check to see if the clock is 0
        Stop = true; // If so, stop the timer

     // check to see if micros() has rolled over, if not,
     // then increment "time" by duration
      _micro < time ? time = _micro : time += duration; 
    }
  }
  return !Stop; // return the state of the timer
}

void ResetTimer()
{
  if(_type) 
    Clock = 0;
  else
    SetTimer(R_clock);

  Stop = false;
}

void StartTimer()
{
  Watch = micros(); // get the initial microseconds at the start of the timer
  Stop = false;
  Paused = false;
  if(_type == UP) 
    Clock = 0;
}

void StopTimer()
{
  Stop = true;
}

void StopTimerAt(unsigned int hours,unsigned int minutes, unsigned int seconds)
{
  if (TimeCheck(hours, minutes, seconds) )
    Stop = true;
}

void PauseTimer()
{
  Paused = true;
}

void ResumeTimer() // You can resume the timer if you ever stop it.
{
  Paused = false;
}

void SetTimer(unsigned int hours, unsigned int minutes, unsigned int seconds)
{
  // This handles invalid time overflow ie 1(H), 0(M), 120(S) -> 1, 2, 0
  unsigned int _S = (seconds / 60), _M = (minutes / 60);
  if(_S) minutes += _S;

  Clock = (minutes * 60) + (seconds % 60);
  R_clock = Clock;
}

void SetTimer(unsigned int seconds)
{
 // StartTimer(seconds / 3600, (seconds / 3600) / 60, seconds % 60);
 Clock = seconds;
 R_clock = Clock;
 Stop = false;
}


int ShowMinutes()
{
    return Clock / 60;
}

int ShowSeconds()
{
  return Clock % 60;
}

int ShowHours()
{
  return Clock / 3600;
}



boolean TimeHasChanged()
{
  return timeFlag;
}

// output true if timer equals requested time
boolean TimeCheck(unsigned int hours, unsigned int minutes, unsigned int seconds) 
{
  return (hours == ShowHours() && minutes == ShowMinutes() && seconds == ShowSeconds());
}