#include <LiquidCrystal_I2C.h>
#define I2C_ADDR    0x27
#define LCD_COLUMNS 20
#define LCD_LINES   4

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

#define sw 8
#define dt 7

 double lastEncode = millis();
 double lastClick = millis();

 int option = 0;

bool lastSwState = LOW;
bool currentSwState = LOW;

bool runProgram1 = false;
bool runProgram2 = false;
bool runProgram3 = false;

double lastDraw = millis();


void encoderMoved()
{
  if(millis() - lastEncode > 5)
  {
    if(digitalRead(dt) == HIGH)
    {
      option = (option+1) % 3;
    }

    if(digitalRead(dt) == LOW)
    {
      option--;
      if(option < 0)
        option = 2;
    }
    lastEncode = millis();  
  }
}

void chooseOption()
{
  if(millis() - lastClick > 5)
  {
    Serial.println("Option : ");
    Serial.print(option);

    lastClick = millis();
  }

}

void drawMenu()
{
  lcd.setCursor(0,0);
  lcd.print("dk");

  lcd.setCursor(6,0);
  lcd.print("uk");

  lcd.setCursor(1,0);
  lcd.print("zp");
  
  lcd.setCursor(1,6);
  lcd.print("pk");
}

void drawDot()
{
  switch(option)
  {
    case 0:
      lcd.setCursor(3,0);
      lcd.print("*");
      lcd.setCursor(9,0);
      lcd.print(" ");
      lcd.setCursor(15,0);
      lcd.print(" ");
      break;
    case 1:
      lcd.setCursor(3,0);
      lcd.print(" ");
      lcd.setCursor(9,0);
      lcd.print("*");
      lcd.setCursor(15,0);
      lcd.print(" ");
      break;
    case 2:
      lcd.setCursor(3,0);
      lcd.print(" ");
      lcd.setCursor(9,0);
      lcd.print(" ");
      lcd.setCursor(15,0);
      lcd.print("*");
      break;
  }
}

void setup() {
  // Init
  lcd.init();
  lcd.backlight();
  // Print something
  lcd.clear();
  drawMenu();

  pinMode (dt,INPUT);
  pinMode (sw,INPUT);

  attachInterrupt(0, encoderMoved, FALLING);
   
  Serial.begin (9600);
}

 void loop() { 
  lastSwState = currentSwState;
  currentSwState = digitalRead(sw);
  if(currentSwState && !lastSwState)
  {
    chooseOption();
  }

  if(millis() - lastDraw > 100)
  {
    drawDot();
    lastDraw = millis();
  }

 }