const int PIN_VERT = A0;
const int PIN_HORIZ = A1;
const int PIN_SEL = A2;

const int PIN_LED_SIZE = 6;
const int PIN_LED[] {3, 5, 6, 9, 10, 11};

class neighbor{
  public:
    int left;
    int right;
    int up;
    int down;

    neighbor(int l, int r, int u, int d);
};

neighbor::neighbor(int l, int r, int u, int d){
  left = l;
  right = r;
  up = u;
  down = d;
}

float vertV;
float horizV;
float selV;

int prevLED = 0;
int currentLED = 0;
int delayTime = 200;

neighbor ledNeighbor[] {
  neighbor(-1, 1, -1, 3), 
  neighbor(0, -1, -1, 2), 
  neighbor(3, -1, 1, 5), 
  neighbor(-1, 2, 0, 4),
  neighbor(-1, 5, 3, -1),
  neighbor(4, -1, 2, -1)};

void setup() {
  Serial.begin(9600);

  pinMode(PIN_VERT, INPUT);
  pinMode(PIN_HORIZ, INPUT);
  pinMode(PIN_SEL, INPUT);

  for (int i = 0; i < PIN_LED_SIZE; i++){
    pinMode(PIN_LED[i], OUTPUT);
  }
}

void loop() {
  vertV = convert(analogRead(PIN_VERT));
  horizV = convert(analogRead(PIN_HORIZ));
  selV = convert(analogRead(PIN_SEL));  

  
  prevLED = currentLED;

  if(vertV == 5.0){
    currentLED = validNeighbor(prevLED, ledNeighbor[prevLED].up);
  }else if(vertV == 0){
    currentLED = validNeighbor(prevLED, ledNeighbor[prevLED].down);
  }else if(horizV == 5.0){
    currentLED = validNeighbor(prevLED, ledNeighbor[prevLED].left);
  }else if(horizV == 0.0){
    currentLED = validNeighbor(prevLED, ledNeighbor[prevLED].right);
  }

  toggleLED(currentLED);

  delay(delayTime);
}

void toggleLED(int index){
  for(int i = 0; i < PIN_LED_SIZE; i++){
    if(i == index){
      digitalWrite(PIN_LED[i], HIGH);
    }else{
      digitalWrite(PIN_LED[i], LOW);
    }
  }
}

float convert(float v){
  return (5.0 / 1023.0) * v;
}

int validNeighbor(int current, int next){
  if(next < 0){
    return current;
  }else{
    return next;
  }
}