#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);

const byte hoch =19;
const byte runter = 2; 
const byte links = 3;
const byte rechts =18;
const byte set = 4;
//const byte reset = ;   

int pos_x = 0;
int pos_y = 0;

int btn_hoch = 0;
int btn_runter = 0;
int btn_links = 0;
int btn_rechts = 0;
int btn_set = 0;


int AA,BA,CA,DA,EA,FA,GA,HA,IA,JA,KA,LA,MA,NA,OA,PA,QA,RA,SA,TA;
int AB,BB,CB,DB,EB,FB,GB,HB,IB,JB,KB,LB,MB,NB,OB,PB,QB,RB,SB,TB;
int AC,BC,CC,DC,EC,FC,GC,HC,IC,JC,KC,LC,MC,NC,OC,PC,QC,RC,SC,TC;
int AD,BD,CD,DD,ED,FD,GD,HD,ID,JD,KD,LD,MD,ND,OD,PD,QD,RD,SD,TD;

void btn_change(){
  if(digitalRead(19) == LOW){
    btn_hoch ++;
  }
  else if(digitalRead(2) == LOW){
    btn_runter ++;
  }
  else if(digitalRead(3) == LOW){
    btn_links ++;
  }
  else if(digitalRead(18) == LOW){
    btn_rechts ++;
  }
}

void btn_reset(){
  btn_hoch = 0;
  btn_runter = 0;
  btn_links = 0;
  btn_rechts = 0;
}

void pos_change(){
  if(btn_hoch == 1){
    pos_y --;
    if(pos_y == -1){
      pos_y ++;
    }
    btn_reset();
  }
  else if(btn_runter == 1){
    pos_y ++;
    if(pos_y == 4){
      pos_y --;
    }
    btn_reset();
  }
  else if(btn_links == 1){
    pos_x --;
    if(pos_x == -1){
      pos_x ++;
    }
    btn_reset();
  }
  else if(btn_rechts == 1){
    pos_x ++;
    if(pos_x == 20){
      pos_x --;
    }
    btn_reset();
  }
}

void blink(){
  lcd.setCursor(pos_x, pos_y);
  lcd.print("O");
  delay(200);
  lcd.setCursor(pos_x, pos_y);
  lcd.print(" ");
  pos_change();
  delay(200);
}

void btn_SET(){
  if(digitalRead(set)== LOW){
    btn_set = 1;
  }
}



void pm(){
  while(btn_set == 1){
    if(pos_x == 0 && pos_y == 0){
      AA = 1;
      break;
    } else if(pos_x == 1 && pos_y == 0){
      BA = 1;
      break;
    } else if(pos_x == 2 && pos_y == 0){
      CA = 1;
      break;
    } else if(pos_x == 3 && pos_y == 0){
      DA == 1;
      break;
    } else if(pos_x == 4 && pos_y == 0){
      EA = 1;
      break;
    } else if(pos_x == 5 && pos_y == 0){
      FA = 1;
      break;
    } else if(pos_x == 6 && pos_y == 0){
      GA = 1;
      break;
    } else if(pos_x == 7 && pos_y == 0){
      HA = 1;
      break;
    } else if(pos_x == 8 && pos_y == 0){
      IA = 1;
      break;
    } else if(pos_x == 9 && pos_y == 0){
      JA = 1;
      break;
    } else if(pos_x == 10 && pos_y == 0){
      KA = 1;
      break;
    } else if(pos_x == 11 && pos_y == 0){
      LA = 1;
      break;
    } else if(pos_x == 12 && pos_y == 0){
      MA = 1;
      break;
    }
  } 
}

void setup() {
  // put your setup code here, to run once:
 lcd.init();
 lcd.backlight();
 pinMode(hoch, INPUT_PULLUP);
 pinMode(runter, INPUT_PULLUP);
 pinMode(links, INPUT_PULLUP);
 pinMode(rechts, INPUT_PULLUP);
 pinMode(set, INPUT_PULLUP);
 attachInterrupt(digitalPinToInterrupt(18), btn_change, FALLING);
 attachInterrupt(digitalPinToInterrupt(3), btn_change, FALLING);
 attachInterrupt(digitalPinToInterrupt(19), btn_change, FALLING);
 attachInterrupt(digitalPinToInterrupt(2), btn_change, FALLING);
 lcd.setCursor(pos_x, pos_y);
 Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  blink();
  btn_SET();
  pm();
}