// ---------------------------
// LED pin assignments
// ---------------------------
const int aled = 4;   // RED   (top-left)
const int bled = 2;   // GREEN (top-right)
const int cled = A3;  // BLUE  (bottom-left)
const int dled = A5;  // YELLOW(bottom-right)

// Array of LED pins in the order A B C D
int leds[4] = { aled, bled, cled, dled };

// ---------------------------
// Active-low LED functions
// (because you wired 5V → LED → R → PIN)
// ---------------------------
void ledOn(int pin) {
  digitalWrite(pin, LOW);   // pin LOW = LED ON
}

void ledOff(int pin) {
  digitalWrite(pin, HIGH);  // pin HIGH = LED OFF
}

// Display a 4-bit number like 1010 on the serial monitor
void print4bit(int value) {
  for (int bit = 3; bit >= 0; bit--) {
    Serial.print((value >> bit) & 1);
  }
  Serial.println();
}

// Light LEDs according to a 4-bit pattern (ABCD)
void showPattern(int pattern) {
  for (int i = 0; i < 4; i++) {
    int bit = (pattern >> (3 - i)) & 1;  // get bit 3→0

    if (bit == 1)
      ledOn(leds[i]);
    else
      ledOff(leds[i]);
  }
}

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

  // Set LED pins as OUTPUT and turn them off
  for (int i = 0; i < 4; i++) {
    pinMode(leds[i], OUTPUT);
    ledOff(leds[i]);
  }

  randomSeed(analogRead(A0));  // randomness
}

void loop() {
  // Example: generate 4 actions
  const int ACTION_COUNT = 4;
  int actions[ACTION_COUNT];

  Serial.println("Generated pattern:");

  for (int i = 0; i < ACTION_COUNT; i++) {

    // Allowed patterns (no diagonals, no singles)
    int validActions[5] = {
      0b1100, // A + B
      0b0011, // C + D
      0b1111, // all 4
      0b1010, // A + C (vertical left)
      0b0101  // B + D (vertical right)
    };

    actions[i] = validActions[random(0, 5)];

    print4bit(actions[i]);   // show in Serial
  }

  Serial.println("Showing pattern...");

  for (int i = 0; i < ACTION_COUNT; i++) {
    showPattern(actions[i]);  // turn LEDs on
    delay(500);

    // turn them all off between flashes
    for (int j = 0; j < 4; j++) ledOff(leds[j]);
    delay(300);
  }

  Serial.println("---- NEW ROUND ----\n");

  delay(1500);
}