const byte leftLEDs[3] = {11, 10, 9};
const byte rightLEDs[3] = {6, 5, 3};

const byte allLEDs[6] = {11, 10, 9, 6, 5, 3};

const byte buttonPin = 2;

void setup() {
  Serial.begin(9600);
  randomSeed(analogRead(0));
  for (int i = 0; i < 3; i++)
  {
    pinMode(leftLEDs[i], OUTPUT);
    pinMode(rightLEDs[i], OUTPUT);
  }
  pinMode(buttonPin, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(buttonPin), buttonHandler, FALLING);
}

bool interrupted = false;
void buttonHandler()
{
  if (!interrupted)
  {
    interrupted = true;
    Serial.println("Interrupted");
  }
}

void Fading()
{
  for (int level = 0; level <= 255; level++)
  {
    for (int i = 0; i < 3; i++)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
    }
    delay(10);
  }
  delay(2000);
  for (int level = 255; level >= 0; level--)
  {
    for (int i = 0; i < 3; i++)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
    }
    delay(10);
  }
}

void Running_Lights_1_Forward()
{
  for (int i = 0; i < 3; i++)
  {
    for (int level = 0; level <= 255; level++)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
      delay(3);
    }
  }
  for (int i = 0; i < 3; i++)
  {
    for (int level = 255; level >= 0; level--)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
      delay(3);
    }
  }
}

void Running_Lights_1_Backward()
{
  for (int i = 2; i >= 0; i--)
  {
    for (int level = 0; level <= 255; level++)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
      delay(3);
    }
  }
  for (int i = 2; i >= 0; i--)
  {
    for (int level = 255; level >= 0; level--)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
      delay(3);
    }
  }
}

void Running_Lights_2_Forward()
{
  for (int i = 0; i < 3; i++)
  {
    for (int level = 0; level <= 255; level++)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
      delay(3);
    }
    for (int level = 255; level >= 0; level--)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
      delay(3);
    }
  }
}

void Running_Lights_2_Backward()
{
  for (int i = 2; i >= 0; i--)
  {
    for (int level = 0; level <= 255; level++)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
      delay(3);
    }
    for (int level = 255; level >= 0; level--)
    {
      analogWrite(leftLEDs[i], level);
      analogWrite(rightLEDs[i], level);
      delay(3);
    }
  }
}

void Random_Lightning()
{
  int LED_number = random(6);
  digitalWrite(allLEDs[LED_number], HIGH);
  delay(500);
  digitalWrite(allLEDs[LED_number], LOW);
}

void Static_Light()
{
  for (int i = 0; i < 6; i++)
  {
    digitalWrite(allLEDs[i], HIGH);
  }
}

void Glimmering()
{
  for (int i = 0; i < 6; i++)
  {
    int random_level = random(100, 256);
    analogWrite(allLEDs[i], random_level);
    delay(10);
  }
}

int mode = 1;
void changeMode()
{
  if (mode < 8)
  {
    mode++;
  }
  else if (mode == 8)
  {
    mode = 1;
  }
}

void loop() {
  if (interrupted)
  {
    noInterrupts();
    changeMode();
    Serial.println(mode);
    interrupted = false;
    interrupts();
  }

  switch (mode)
  {
    case 1:
      Fading();
      break;
    case 2:
      Running_Lights_1_Forward();
      break;
    case 3:
      Running_Lights_1_Backward();
      break;
    case 4:
      Running_Lights_2_Forward();
      break;
    case 5:
      Running_Lights_2_Backward();
      break;
    case 6:
      Random_Lightning();
      break;
    case 7:
      Static_Light();
      break;
    case 8:
      Glimmering();
      break;
  }
}