#include <Wire.h>

#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27,16,2);
const int  Up_buttonPin   = 2;
const int  Down_buttonPin = 3;
const int  Start_buttonPin = 4;

int buttonPushCounter = 0; 

int up_buttonState = 0;        
int up_lastButtonState = 0;     

int down_buttonState = 0;         
int down_lastButtonState = 0;     

int start_buttonState = 0;
int start_lastButtonState = 0;

bool bPress = false;

unsigned long seconds = 1000L; 
unsigned long minutes = seconds * 60;
unsigned long hours = minutes * 60;

const int REL1 = 8;
const int REL2 = 9;

void setup()

{

  Serial.begin(9600);

  pinMode( Up_buttonPin , INPUT_PULLUP);
  pinMode( Down_buttonPin , INPUT_PULLUP);

  pinMode(REL1, OUTPUT);
  pinMode(REL2, OUTPUT);

  lcd.init();                  

  lcd.backlight();

  lcd.setCursor(0,0);

  lcd.print("CountDown Timer:");

  lcd.setCursor(7,1);

  lcd.print(buttonPushCounter);

}

void loop()
{
   checkUp();

   checkDown();

   checktimer();

   if( bPress){

       bPress = false;

      lcd.setCursor(0,0);

      lcd.print("****************");

      lcd.setCursor(7,1);
      lcd.print(buttonPushCounter);
      

   }
}

void checkUp()

{

  up_buttonState = digitalRead(Up_buttonPin);

  if (up_buttonState != up_lastButtonState) {

    if (up_buttonState == LOW && buttonPushCounter<59 ) {

        bPress = true;

      buttonPushCounter++;

      Serial.println("on");

      Serial.print("number of button pushes: ");

      Serial.println(buttonPushCounter);
    }

    else if (up_buttonState == LOW && buttonPushCounter>=59 ) {

        bPress = true;

      buttonPushCounter = -1;
      buttonPushCounter++;

      Serial.println("on");

      Serial.print("number of button pushes: ");

      Serial.println(buttonPushCounter);
    }


 else {

      Serial.println("off");

    }

    delay(50);

  }

  up_lastButtonState = up_buttonState;

}

void checkDown()

{

  down_buttonState = digitalRead(Down_buttonPin);

  if (down_buttonState != down_lastButtonState) {


    if (down_buttonState == LOW && buttonPushCounter<=59 && buttonPushCounter>0) {

        bPress = true;

      buttonPushCounter--;

      Serial.println("on");

      Serial.print("number of button pushes: ");

      Serial.println(buttonPushCounter);
    }
    
    else if (down_buttonState == LOW && buttonPushCounter>=0) {

        bPress = true;

      buttonPushCounter = 60;
      buttonPushCounter--;

      Serial.println("on");

      Serial.print("number of button pushes: ");

      Serial.println(buttonPushCounter);
    }
     else {
      Serial.println("off");
    }
    delay(50);
  }
  down_lastButtonState = down_buttonState;
}



//////////////////////////////////////////////////////////////////////////////

void checktimer()
{

  start_buttonState = digitalRead(Start_buttonPin);

  if (start_buttonState != start_lastButtonState) {


    if (start_buttonState == LOW && buttonPushCounter <= 59 ) {

      bPress = true;

      lcd.clear();
      
      for(buttonPushCounter <= 59; buttonPushCounter >= 1; buttonPushCounter--){
  
      lcd.setCursor(5,1);
      lcd.print(buttonPushCounter-1);

      lcd.setCursor(7,1);
      lcd.print(":");
      
      int i = 59;
      for(i<=59; i>=0;i--){
      lcd.setCursor(9,1);
      lcd.print(i);
      delay(1 * seconds);
      }
      //delay(1 * minutes);
      //lcd.clear();
      }

      digitalWrite(REL1, 1);
      digitalWrite(REL2, 0);
      
      delay(0.5 * seconds);  

      digitalWrite(REL1, 0);
      digitalWrite(REL2, 0);
     
      delay(2 * seconds); 
      ////////////////////////////////////////

      digitalWrite(REL1, 0);
      digitalWrite(REL2, 1);
     
      delay(0.5 * seconds); 

      digitalWrite(REL1, 0);
      digitalWrite(REL2, 0);

      delay(0.5 * seconds); 
      ////////////////////////////////////////

      Serial.println("on");

      Serial.print("number of button pushes: ");

      Serial.println(buttonPushCounter);

      lcd.clear();


    }
    else {
      Serial.println("off");
    }
    delay(50);
    }
    
  start_lastButtonState = start_buttonState;
}