// Pin definitions
const int GoingDownLED = 1;
const int GoingUpLED = 2;
const int Floor0LED = 3;
const int Floor1LED = 4;
const int EmergencyLED = 5;
const int MotorForwards = 13;
const int MotorBackwards = 14;

const int CallButton = 6;
const int Level0Button = 7;
const int Level1Button = 8;
const int DoorsClosed1Sensor = 9;
const int DoorsClosed0Sensor = 10;
const int Floor1Sensor = 11;
const int Floor0Sensor = 12;

enum ElevatorState {
  IDLE,
  MOVING_UP,
  MOVING_DOWN,
  EMERGENCY
};

ElevatorState currentState = IDLE;
bool callButtonHandled = false;
bool level0ButtonHandled = false;
bool level1ButtonHandled = false;

void setup() {
  // Initialize all pins
  pinMode(GoingDownLED, OUTPUT);
  pinMode(GoingUpLED, OUTPUT);
  pinMode(Floor0LED, OUTPUT);
  pinMode(Floor1LED, OUTPUT);
  pinMode(EmergencyLED, OUTPUT);
  pinMode(MotorForwards, OUTPUT);
  pinMode(MotorBackwards, OUTPUT);

  pinMode(CallButton, INPUT);
  pinMode(Level0Button, INPUT);
  pinMode(Level1Button, INPUT);
  pinMode(DoorsClosed1Sensor, INPUT);
  pinMode(DoorsClosed0Sensor, INPUT);
  pinMode(Floor1Sensor, INPUT);
  pinMode(Floor0Sensor, INPUT);

  // Set initial states
  initializeOutputs();
}

void loop() {
  updateFloorLEDs();

  if (handleEmergency()) {
    currentState = EMERGENCY;
    return;
  }

  if (currentState == IDLE) {
    if (digitalRead(CallButton) == HIGH && !callButtonHandled && digitalRead(DoorsClosed1Sensor) == HIGH && digitalRead(DoorsClosed0Sensor) == HIGH) {
      callButtonHandled = true;
      if (digitalRead(Floor1Sensor) == HIGH) {
        currentState = MOVING_DOWN;
        moveDown();
      } else if (digitalRead(Floor0Sensor) == HIGH) {
        currentState = MOVING_UP;
        moveUp();
      }
    } else if (digitalRead(CallButton) == LOW) {
      callButtonHandled = false;
    }

    if (digitalRead(Level1Button) == HIGH && !level1ButtonHandled && digitalRead(DoorsClosed1Sensor) == HIGH && digitalRead(DoorsClosed0Sensor) == HIGH && digitalRead(Floor0Sensor) == HIGH) {
      level1ButtonHandled = true;
      currentState = MOVING_UP;
      moveUp();
    } else if (digitalRead(Level1Button) == LOW) {
      level1ButtonHandled = false;
    }

    if (digitalRead(Level0Button) == HIGH && !level0ButtonHandled && digitalRead(DoorsClosed1Sensor) == HIGH && digitalRead(DoorsClosed0Sensor) == HIGH && digitalRead(Floor1Sensor) == HIGH) {
      level0ButtonHandled = true;
      currentState = MOVING_DOWN;
      moveDown();
    } else if (digitalRead(Level0Button) == LOW) {
      level0ButtonHandled = false;
    }
  }
}

// Function to initialize outputs
void initializeOutputs() {
  digitalWrite(GoingDownLED, LOW);
  digitalWrite(GoingUpLED, LOW);
  digitalWrite(Floor0LED, LOW);
  digitalWrite(Floor1LED, LOW);
  digitalWrite(EmergencyLED, LOW);
  digitalWrite(MotorForwards, LOW);
  digitalWrite(MotorBackwards, LOW);
}

// Function to update LEDs based on floor and door sensors
void updateFloorLEDs() {
  if (digitalRead(Floor1Sensor) == HIGH && digitalRead(DoorsClosed1Sensor) == HIGH) {
    digitalWrite(Floor1LED, HIGH);
    digitalWrite(Floor0LED, LOW);
    digitalWrite(GoingUpLED, LOW);
    digitalWrite(GoingDownLED, LOW);
    currentState = IDLE;
  } else if (digitalRead(Floor0Sensor) == HIGH && digitalRead(DoorsClosed0Sensor) == HIGH) {
    digitalWrite(Floor1LED, LOW);
    digitalWrite(Floor0LED, HIGH);
    digitalWrite(GoingUpLED, LOW);
    digitalWrite(GoingDownLED, LOW);
    currentState = IDLE;
  } else if (digitalRead(DoorsClosed1Sensor) == LOW) {
    digitalWrite(Floor1LED, LOW);
  } else if (digitalRead(DoorsClosed0Sensor) == LOW) {
    digitalWrite(Floor0LED, LOW);
  }
}

// Function to handle emergency state
bool handleEmergency() {
  if (digitalRead(Floor1Sensor) == LOW && digitalRead(Floor0Sensor) == LOW) {
    digitalWrite(EmergencyLED, HIGH);
    delay(500);
    digitalWrite(EmergencyLED, LOW);
    delay(500);
    digitalWrite(GoingDownLED, LOW);
    digitalWrite(GoingUpLED, LOW);
    digitalWrite(Floor0LED, LOW);
    digitalWrite(Floor1LED, LOW);
    currentState = IDLE;
    return true;
  }
  return false;
}

// Function to move elevator up
void moveUp() {
  digitalWrite(Floor0LED, LOW);
  digitalWrite(GoingUpLED, HIGH);
  delay(2000);
  digitalWrite(MotorForwards, HIGH);
  delay(10000);
  digitalWrite(MotorForwards, LOW);
  delay(1000);
  digitalWrite(Floor1LED, HIGH);
  digitalWrite(GoingUpLED, LOW);
}

// Function to move elevator down
void moveDown() {
  digitalWrite(Floor1LED, LOW);
  digitalWrite(GoingDownLED, HIGH);
  delay(2000);
  digitalWrite(MotorBackwards, HIGH);
  delay(10000);
  digitalWrite(MotorBackwards, LOW);
  delay(1000);
  digitalWrite(Floor0LED, HIGH);
  digitalWrite(GoingDownLED, LOW);
}