int oldx, oldy;
bool isMovedX = false;
bool isMovedY = false;
int led_pin[] = {11, 10, 9, 6, 5, 3};
int active_pin = 0;
int active_bright = 250;
int lim = 25;
int lastButton = LOW;
int currButton = LOW;

void setup() {
  pinMode(led_pin[active_pin], OUTPUT);
  digitalWrite(led_pin[active_pin], HIGH);
  for(int i = 1; i < 6; i++)
  {
    pinMode(led_pin[i], OUTPUT);
    digitalWrite(led_pin[i], LOW);
  }  

  pinMode(2, INPUT_PULLUP);
  pinMode(A1, INPUT);
  pinMode(A2, INPUT);
}

void loop() {
  int x = analogRead(A1);
  int y = analogRead(A2);

  isMovedX = (((x < 512 - lim) || (x > 512 + lim)) && (x != oldx)) ? true : false;
  isMovedY = (((y < 512 - lim) || (y > 512 + lim)) && (y != oldy)) ? true : false;

  if(isMovedX)
  {
    LedShift(x);
  }
  if(isMovedY)
  {
    Brightness(y);
  }

  PressButton();

  oldx = x;
  oldy = y;
  delay(100);
}

void PressButton()
{
  static unsigned long timer;
  if(timer + 50 > millis()) return;

  currButton = digitalRead(2);
  if(currButton == LOW && lastButton == HIGH)
  {
    digitalWrite(led_pin[active_pin], LOW);
    active_pin = 0;
    analogWrite(led_pin[active_pin], active_bright);
  }
  lastButton = currButton;
  timer = millis();
}

void Brightness (int y)
{
  if((y > 512) && (active_bright < 241))
  {
    active_bright += 10;
    analogWrite(led_pin[active_pin], active_bright);
  }
  if((y < 512) && (active_bright > 9))
  {
    active_bright -= 10;
    analogWrite(led_pin[active_pin], active_bright);
  } 
}

void LedShift(int x)
{
  if((x > 512) && (active_pin > 0))
  {
    digitalWrite(led_pin[active_pin], LOW);
    analogWrite(led_pin[active_pin - 1], active_bright);
    active_pin--;
  }

  if((x < 512) && (active_pin < 5))
  {
    digitalWrite(led_pin[active_pin], LOW);
    analogWrite(led_pin[active_pin + 1], active_bright);
    active_pin++;
  }
}