// pin tombol
const int buttonPin1 = 2; 
const int buttonPin2 = 3;  
const int buttonPin3 = 4;  


const int ledPin1 = 12;  
const int ledPin2 = 11;  
const int ledPin3 = 10;  
const int ledPin4 = 5;   

// Variabel status tombol
bool lastButton1State = HIGH; 
bool lastButton2State = HIGH; 
bool lastButton3State = HIGH; 

// Variabel untuk status LED
bool led1State = LOW; 
bool led2State = LOW;
bool led3State = LOW; 
bool led4State = LOW; 


int currentTask = 0; // 0 = Greeting, 1 = Selection, 2 = Task A, 3 = Task B, 4 = Task C

// Timer untuk Task B
unsigned long previousMillis = 0;
const long interval = 1000; // Interval perubahan 1 detik untuk Task B
int counter = 0; 

void setup() {
  // Set pin tombol sebagai input dengan pull-up internal
  pinMode(buttonPin1, INPUT_PULLUP);
  pinMode(buttonPin2, INPUT_PULLUP);
  pinMode(buttonPin3, INPUT_PULLUP);

  // Set pin LED sebagai output
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  pinMode(ledPin4, OUTPUT);

  // Matikan semua LED di awal
  digitalWrite(ledPin1, LOW);
  digitalWrite(ledPin2, LOW);
  digitalWrite(ledPin3, LOW);
  digitalWrite(ledPin4, LOW);

  // Greeting
  greeting();
}

void loop() {
  // Baca status tombol
  bool button1State = digitalRead(buttonPin1);
  bool button2State = digitalRead(buttonPin2);
  bool button3State = digitalRead(buttonPin3);

  switch (currentTask) {
    case 0: // Greeting
      // Tidak ada interaksi tombol saat greeting
      return;

    case 1: // Selection
      // LED kuning menyala untuk menandakan masuk ke task
      digitalWrite(ledPin4, HIGH);

      // Pindah ke task berikutnya jika tombol ditekan
      if (button1State == LOW && lastButton1State == HIGH) {
        delay(50); // Debounce delay
        currentTask = 2; // Pindah ke Task A
      } else if (button2State == LOW && lastButton2State == HIGH) {
        delay(50); // Debounce delay
        currentTask = 3; // Pindah ke Task B
      } else if (button3State == LOW && lastButton3State == HIGH) {
        delay(50); // Debounce delay
        currentTask = 4; // Pindah ke Task C
      }
      lastButton1State = button1State;
      lastButton2State = button2State;
      lastButton3State = button3State;
      break;

    case 2: // Task A
      // Toggle LED1 dengan Button 1
      if (button1State == LOW && lastButton1State == HIGH) {
        led1State = !led1State;
        digitalWrite(ledPin1, led1State);
        delay(50); // Debounce delay
      }
      lastButton1State = button1State;

      // Toggle LED2 dengan Button 2
      if (button2State == LOW && lastButton2State == HIGH) {
        led2State = !led2State;
        digitalWrite(ledPin2, led2State);
        delay(50); // Debounce delay
      }
      lastButton2State = button2State;

      // Toggle LED3 dan LED4 dengan Button 3
      if (button3State == LOW && lastButton3State == HIGH) {
        led3State = !led3State;
        led4State = !led4State; // LED4 mengikuti LED3
        digitalWrite(ledPin3, led3State);
        digitalWrite(ledPin4, led4State);
        delay(50); // Debounce delay
      }
      lastButton3State = button3State;
      break;

    case 3: // Task B
      // Binary counter 4-bit
      unsigned long currentMillis = millis();
      if (currentMillis - previousMillis >= interval) {
        previousMillis = currentMillis;
        counter++;
        if (counter > 15) counter = 0; // Reset counter jika lebih dari 15 (4-bit)

        // Update LED status sesuai counter
        digitalWrite(ledPin4, HIGH); // MSB
        digitalWrite(ledPin3, counter & 1); // LSB
        // Update LED lainnya sesuai bit counter
      }
      break;

    case 4: // Task C
      // Toggle LED1 dengan Button 1
      if (button1State == LOW && lastButton1State == HIGH) {
        led1State = !led1State;
        digitalWrite(ledPin1, led1State);
        delay(50); // Debounce delay
      }

      // Toggle LED2 dengan Button 2 (LED1 harus menyala)
      if (led1State == HIGH && button2State == LOW && lastButton2State == HIGH) {
        led2State = !led2State;
        digitalWrite(ledPin2, led2State);
        delay(50); // Debounce delay
      }

      // Toggle LED3 dan LED4 dengan Button 3 (LED1 mati dan LED2 menyala)
      if (led1State == LOW && led2State == HIGH && button3State == LOW && lastButton3State == HIGH) {
        led3State = !led3State;
        led4State = !led4State;
        digitalWrite(ledPin3, led3State);
        digitalWrite(ledPin4, led4State);
        delay(50); // Debounce delay
      }

      lastButton1State = button1State;
      lastButton2State = button2State;
      lastButton3State = button3State;
      break;
  }
}

void greeting() {
  // Menyalakan LED sesuai urutan dengan delay 2 detik
  digitalWrite(ledPin1, HIGH);
  delay(2000);
  digitalWrite(ledPin1, LOW);
  
  digitalWrite(ledPin2, HIGH);
  delay(2000);
  digitalWrite(ledPin2, LOW);
  
  digitalWrite(ledPin3, HIGH);
  delay(2000);
  digitalWrite(ledPin3, LOW);
  
  digitalWrite(ledPin4, HIGH);
  delay(2000);
  digitalWrite(ledPin4, LOW);

  // Setelah greeting, pindah ke task selection
  currentTask = 1;
}