const int buttonPins[] = {2, 3, 4, 5};  // Blue, Red, Green, Yellow buttons
const int ledPins[] = {6, 7, 8, 9};     // Blue, Red, Green, Yellow LEDs
const int activeLED = 13;
int sequence[50]; //sets length of input list
int userInput[50]; //Set length of user input list
int roundNumber = 1; //set round to round 1
int userInputIndex = 0;
bool isGameOver = false; //keeps track of state of game
bool isCorrect = true;
void setup() { //setup uses for loop to set the pinmodes for the led's and buttonPins
  for (int i = 0; i < 4; i++) {
    pinMode(ledPins[i], OUTPUT);
    pinMode(buttonPins[i], INPUT_PULLUP);
  }
  pinMode(activeLED, OUTPUT);
  Serial.begin(9600);
  randomSeed(analogRead(0)); //ensures the random sequence does not repeat itself each time the game runs
}

void loop() {
  if (isGameOver) {// if the player loses the game, these three for loops run so that
    				// every LED will flash three times, indicating the player has lost
    for (int i = 0; i < 3; i++) {
      for (int j = 0; j < 4; j++) digitalWrite(ledPins[j], HIGH);
      delay(500);
      for (int j = 0; j < 4; j++) digitalWrite(ledPins[j], LOW);
      delay(500);
    }
    isGameOver = false; //reset game status and round number to 1 if the if statement in line 20 is true
    isCorrect = true;
    roundNumber = 1;
    userInputIndex = 0;
    return;
  }

  for (int i = 0; i < roundNumber; i++) { //for loop runs based off round number
    if (i == roundNumber - 1) sequence[i] = random(0, 4); // checks the round number, and adds another value to the sequence list
    digitalWrite(ledPins[sequence[i]], HIGH);//the following lines flash the lights using the sequence list
    delay(500);
    digitalWrite(ledPins[sequence[i]], LOW);
    delay(500);
  }

  digitalWrite(activeLED, HIGH); // turn on LED to indicate when the user should press buttons
  for (int i = 0; i < roundNumber; i++) { //for loop runs based off round number
    bool buttonPressed = false;
    while (!buttonPressed) { //while button is not pressed, the if statement checks which button was pressed
      for (int j = 0; j < 4; j++) {
        if (digitalRead(buttonPins[j]) == LOW) {
          delay(50);
          userInput[userInputIndex++] = j;
          Serial.println(j);
          while (digitalRead(buttonPins[j]) == LOW);
          buttonPressed = true;
        }
      }
    }
	// for loop compares the list values of sequence and userinput. if values are not equal, player loses
    if (sequence[userInputIndex-1] != userInput[userInputIndex - 1]) {
      isCorrect = false;
      break;
    }
  }
  digitalWrite(activeLED, LOW);
	// for loop compares the list values of sequence and userinput. if values are not equal, player loses
  for (int i = 0; i < roundNumber; i++) {
    if (sequence[i] != userInput[i]) {
      isCorrect = false;
      break;
    }
  }

  if (isCorrect) { //If player input matches the sequence, then round number is increased
    				//if "isCorrect is false, the player loses
    roundNumber++;
    userInputIndex = 0;
  } else {
    isGameOver = true;
  }
  delay(1000);
}