#include <Keypad.h>
#include <LiquidCrystal.h>

// Pins for the RGB LED and Buzzer
const int PIN_R = 3;
const int PIN_G = 4;
const int PIN_B = 5;
const int BUZZER_PIN = 6;
const int FIRE_SENSOR_PIN = 7; // Fire detection sensor input

// Initialize the LCD with the correct pins
LiquidCrystal lcd(52, 50, 48, 46, 44, 42);  // RS=52, E=50, D4=48, D5=46, D6=44, D7=42

// Define the Keypad setup
const byte ROWS = 4;  // Four rows
const byte COLS = 3;  // Three columns

// Define the keys on the keypad
char keys[ROWS][COLS] = {
  {'1', '2', '3'},
  {'4', '5', '6'},
  {'7', '8', '9'},
  {'*', '0', '#'}
};

// Connect keypad rows and columns to these pins
byte rowPins[ROWS] = {37, 39, 41, 43};  // Update these pins as necessary
byte colPins[COLS] = {45, 47, 49};      // Update these pins as necessary

// Create the keypad object
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// Set the correct password
String correctPassword = "1234";
String enteredPassword = "";

// State variable to keep track of system mode
enum SystemState {READY, FIRE_DETECTION, STANDBY} systemState = READY;

// Function to control the RGB LED
void setRGB(int r, int g, int b) {
  analogWrite(PIN_R, r);
  analogWrite(PIN_G, g);
  analogWrite(PIN_B, b);
}

// Function to control the Buzzer
void beep(int times, int duration = 200) {
  for (int i = 0; i < times; i++) {
    tone(BUZZER_PIN, 1000, duration);
    delay(duration);
    noTone(BUZZER_PIN);
    delay(duration);
  }
}

// Smooth scrolling text function
void scrollTextNonBlocking(String message, unsigned long scrollSpeed = 300) {
  static unsigned long lastScrollTime = 0;
  static int currentPos = 0;
  static String scrollMessage;

  if (message != scrollMessage) {
    scrollMessage = "                " + message;  // Add 16 spaces at the start
    currentPos = 0;
  }

  if (millis() - lastScrollTime >= scrollSpeed) {
    lastScrollTime = millis();
    lcd.setCursor(0, 1);  // Set cursor to second line
    lcd.print(scrollMessage.substring(currentPos, currentPos + 16));  // Print 16 chars of the message
    currentPos++;
    if (currentPos >= scrollMessage.length()) {
      currentPos = 0;
    }
  }
}

void setup() {
  // Initialize the RGB LED and Buzzer pins
  pinMode(PIN_R, OUTPUT);
  pinMode(PIN_G, OUTPUT);
  pinMode(PIN_B, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(FIRE_SENSOR_PIN, INPUT); // Set fire sensor pin as input

  // System Initialization
  setRGB(0, 0, 255);  // Blue LED for system ready
  beep(2);  // 2 beeps for initialization

  // Initialize the LCD
  lcd.begin(16, 2);
  lcd.clear();
  lcd.print("System Ready");
  delay(2000);
  
  // Display the initial message
  lcd.clear();
  lcd.print("Enter Security");
  lcd.setCursor(0, 1);
  lcd.print("Code:");
}

void loop() {
  char key = keypad.getKey();  // Read the key pressed

  if (key) {  // If a key is pressed
    if (key == '#') {  // If the key is the '#' key, check the password
      lcd.clear();
      if (enteredPassword == correctPassword) {
        switch (systemState) {
          case READY:
            // Prompt user to arm or standby
            setRGB(0, 255, 0);  // Green LED for success
            beep(3);  // 3 beeps for correct input
            lcd.print("Access Granted");
            delay(2000);
            lcd.clear();
            lcd.print("1: Arm Fire");
            lcd.setCursor(0, 1);
            lcd.print("2: Standby");

            // Wait for the user to select an option
            while (true) {
              char option = keypad.getKey();
              if (option == '1') {
                setRGB(255, 0, 0);  // Constant Red for Fire Detection Activated
                lcd.clear();
                lcd.print("Fire Detect Mode");
                systemState = FIRE_DETECTION;
                break;
              } else if (option == '2') {
                setRGB(0, 0, 255);  // Constant Blue for system standby
                lcd.clear();
                lcd.print("System Standby");
                systemState = STANDBY;
                break;
              }
            }
            break;

          case FIRE_DETECTION:
          case STANDBY:
            // Neutralize and return to ready state
            setRGB(0, 0, 255);  // Blue for system ready
            beep(1);  // 1 beep for disarming
            lcd.clear();
            lcd.print("System Disarmed");
            systemState = READY;
            delay(2000);
            lcd.clear();
            lcd.print("Enter Security");
            lcd.setCursor(0, 1);
            lcd.print("Code:");
            break;
        }
      } else {
        setRGB(255, 0, 0);  // Constant Red LED for failure
        tone(BUZZER_PIN, 1000);  // Continuous beep for incorrect input
        lcd.print("Access Denied");
        delay(3000);
        noTone(BUZZER_PIN);  // Stop the beep
        lcd.clear();
        lcd.print("Enter Security");
        lcd.setCursor(0, 1);
        lcd.print("Code:");
      }
      enteredPassword = "";  // Clear the entered password
    } else if (key == '*') {  // If the key is the '*' key, clear the current entry
      enteredPassword = "";
      lcd.setCursor(0, 1);
      lcd.print("                ");  // Clear the second line of the LCD
    } else {
      // Add the pressed key to the password
      enteredPassword += key;
      lcd.setCursor(0, 1);
      lcd.print(enteredPassword);
    }
  }

  // Handle the states as per logic
  switch (systemState) {
    case FIRE_DETECTION:
      setRGB(255, 0, 0);  // Constant Red for fire detection
      lcd.setCursor(0, 0);
      lcd.print("Fire Detect Mode");
      scrollTextNonBlocking("Fire Detect Active");
      
      // Check the fire detection sensor
      if (digitalRead(FIRE_SENSOR_PIN) == HIGH) {
        tone(BUZZER_PIN, 1000);  // Continuous beep if fire is detected
      } else {
        noTone(BUZZER_PIN);  // Stop the beep if no fire is detected
      }
      break;

    case STANDBY:
      setRGB(0, 0, 255);  // Constant Blue for standby
      lcd.setCursor(0, 0);
      lcd.print("System Standby");
      scrollTextNonBlocking("System in Standby");
      break;

    case READY:
    default:
      // No action needed in READY state
      break;
  }
}