#include <ArduinoQueue.h>

#define DOORCLOSED 0
#define SEAT1 4
#define SEAT2 7
#define SEAT3 10
#define SEAT4 13

#define RED1 3
#define GREEN1 2
#define RED2 6
#define GREEN2 5
#define RED3 9
#define GREEN3 8
#define RED4 12
#define GREEN4 11

#define GREENDURATION 3000 // 3 seconds



// Structure to store button press information
struct ButtonPress {
  int buttonNumber;
};

// Create a queue of ButtonPress structures with a maximum capacity of 10 items
ArduinoQueue<ButtonPress> buttonQueue(10);

unsigned long previousGreenMillis = 0;
bool doorClosedState = false;
bool prevDoorState = false; // Variable to keep track of the previous state of the door button
int currentGreenLedPin = -1;
bool greenLedOff = true;


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

  // Initialize button pins
  pinMode(DOORCLOSED, INPUT_PULLUP);
  pinMode(SEAT1, INPUT_PULLUP);
  pinMode(SEAT2, INPUT_PULLUP);
  pinMode(SEAT3, INPUT_PULLUP);
  pinMode(SEAT4, INPUT_PULLUP);

  // Initialize LED pins
  pinMode(RED1, OUTPUT);
  pinMode(GREEN1, OUTPUT);
  pinMode(RED2, OUTPUT);
  pinMode(GREEN2, OUTPUT);
  pinMode(RED3, OUTPUT);
  pinMode(GREEN3, OUTPUT);
  pinMode(RED4, OUTPUT);
  pinMode(GREEN4, OUTPUT);

  // Turn off all LEDs initially
  digitalWrite(RED1, LOW);
  digitalWrite(GREEN1, LOW);
  digitalWrite(RED2, LOW);
  digitalWrite(GREEN2, LOW);
  digitalWrite(RED3, LOW);
  digitalWrite(GREEN3, LOW);
  digitalWrite(RED4, LOW);
  digitalWrite(GREEN4, LOW);
    // Read the initial state of the door and set prevDoorState accordingly
  prevDoorState = digitalRead(DOORCLOSED);
}

void loop() {
  // Check button presses
  checkButton(SEAT1, 1, RED1, GREEN1);
  checkButton(SEAT2, 2, RED2, GREEN2);
  checkButton(SEAT3, 3, RED3, GREEN3);
  checkButton(SEAT4, 4, RED4, GREEN4);

  // Check if door button state has changed
  bool doorState = digitalRead(DOORCLOSED);
  if (doorState != prevDoorState && doorState == LOW) { // Door button pressed
    doorClosedState = !doorClosedState; // Toggle the state
    Serial.print("Door closed state: ");
    Serial.println(doorClosedState ? "LOCKED" : "UNLOCKED");
    if (!doorClosedState && !buttonQueue.isEmpty()) {
      buttonQueue.dequeue();
      Serial.print("Queue advanced. ");
      Serial.print(buttonQueue.itemCount());
      Serial.println(" in queue.");
      // Reset the timer for turning off the previous green LED
      previousGreenMillis = millis();
      // Turn off the current green LED
      if (currentGreenLedPin != -1) {
        digitalWrite(currentGreenLedPin, LOW);
        currentGreenLedPin = -1;
        greenLedOff = true; // Set the flag indicating the green LED is off
      }
    }
  }
  prevDoorState = doorState;

  // Check if any green LEDs need to be turned off after 3 seconds
  if (millis() - previousGreenMillis >= GREENDURATION) {
    // Turn off the current green LED
    if (currentGreenLedPin != -1) {
      digitalWrite(currentGreenLedPin, LOW);
      currentGreenLedPin = -1;
      greenLedOff = true; // Set the flag indicating the green LED is off
    }
  }

  // Check if the green LED is confirmed to be off before proceeding
  if (greenLedOff) {
    // Proceed with checking other button presses or any other necessary tasks
    // Reset the flag
    greenLedOff = false;
  }

  delay(100); // Small delay for stability
}

// Function to check a button for a press and enqueue it if pressed
// Define debounce delay in milliseconds
#define DEBOUNCE_DELAY 500

// Function to check a button for a press and enqueue it if pressed
// Function to check a button for a press and enqueue it if pressed
void checkButton(int buttonPin, int buttonNumber, int redLedPin, int greenLedPin) {
    int buttonState = digitalRead(buttonPin);

    // Check if the button state is LOW, indicating a press
    if (buttonState == LOW) {
        if (!buttonQueue.isFull()) {
            ButtonPress newPress;
            newPress.buttonNumber = buttonNumber;
            buttonQueue.enqueue(newPress); // Enqueue the button press

            // Turn on the red LED
            digitalWrite(redLedPin, HIGH);
            digitalWrite(greenLedPin, LOW); // Ensure green LED is off
        } else {
            Serial.println("Queue is full! Cannot add more.");
        }

        // Print the number of items in the queue
        Serial.print("Number of items in the queue: ");
        Serial.println(buttonQueue.itemCount());
    }

    // Check if the front of the queue matches this button press and activate respective green LED
    if (!buttonQueue.isEmpty() && buttonQueue.front().buttonNumber == buttonNumber) {
        // Turn off the currently lit green LED
        if (currentGreenLedPin != -1) {
            digitalWrite(currentGreenLedPin, LOW);
        }
        // Turn on the new green LED
        digitalWrite(greenLedPin, HIGH);
        digitalWrite(redLedPin, LOW); // Turn off the red LED
        currentGreenLedPin = greenLedPin; // Update the current green LED pin
    }
}