#include <LiquidCrystal.h>
//Vyganto Jonaicio Lab3 - 2
LiquidCrystal lcd(12, 11, 10, 9, 8, 7);
#define LED1_PIN 4
#define LED2_PIN 6
#define BUTTON_UP_PIN 2
#define BUTTON_DOWM_PIN 3
#define BUTTON_OK_PIN 5

String menu[8] = {"1 - meniu","2 - meniu","3 - meniu",
  "4 - meniu","5 - meniu","6 - meniu","7 - meniu","8 - meniu"};
char pointer = '>';
int pointerPos = 0;
int d = 100, pdelay = 50;
byte lastOk = LOW, valueOk;
int on = 0;
unsigned long buttonTime;

void setup() {
lcd.begin(16, 2);
pinMode(LED1_PIN, OUTPUT);
pinMode(LED2_PIN, OUTPUT);
pinMode(BUTTON_UP_PIN, INPUT);
pinMode(BUTTON_DOWM_PIN, INPUT);
pinMode(BUTTON_OK_PIN, INPUT);  
buttonTime = millis();
}

void loop() {
  
  valueOk = digitalRead(BUTTON_OK_PIN);
  attachInterrupt(digitalPinToInterrupt(BUTTON_DOWM_PIN), downB, CHANGE);
  attachInterrupt(digitalPinToInterrupt(BUTTON_UP_PIN), upB, CHANGE);
  delay(d);
  printLcd(pointerPos);
}

void downB(){ 
  if (buttonTime + pdelay < millis() ) {
    if (digitalRead(BUTTON_DOWM_PIN) == HIGH) pointerPos++; 
    if(pointerPos>7) pointerPos=0;
    buttonTime = millis();
  }
}
void upB(){ 
  if (buttonTime + pdelay < millis() ) {
    if (digitalRead(BUTTON_UP_PIN) == HIGH) pointerPos--; 
    if(pointerPos<0) pointerPos=7;
    buttonTime = millis();
  }
}

void printLcd(int a){
  valueOk = digitalRead(BUTTON_OK_PIN);
  if(a % 2 == 0){
    lcd.setCursor(0, 0);
    lcd.print(pointer + menu[a]);
    if (on == HIGH) lcd.print(" ON");
    else lcd.print("   ");
    lcd.setCursor(0, 1);
    lcd.print(" " + menu[a+1]);
    pressed();
    delay(d);
    lcd.setCursor(0, 0);
    lcd.print(" " + menu[a]);//blink pointer
  }
  else{
    lcd.setCursor(0, 0);
    lcd.print(" " + menu[a-1]);
    lcd.setCursor(0, 1);
    lcd.print(pointer + menu[a]);
    if (on == HIGH) lcd.print(" OFF");
    else lcd.print("    ");
    pressed();
    delay(d);
    lcd.setCursor(0, 1);
    lcd.print(" " + menu[a]);//blink pointer
  }
  valueOk = digitalRead(BUTTON_OK_PIN);
}

void pressed(){
  if (valueOk != lastOk) {
    lastOk = valueOk;
    if (valueOk == LOW) {
      //on = (on == HIGH) ? LOW: HIGH;
      on = LOW;
      if (pointerPos % 2 == 0) digitalWrite(LED1_PIN, HIGH), digitalWrite(LED2_PIN, HIGH);
      else digitalWrite(LED1_PIN, LOW), digitalWrite(LED2_PIN, LOW);
    }
    else on = HIGH;
  }
}