#include <Keypad.h>
#include <LiquidCrystal.h>
#include <Preferences.h>
#include <Ticker.h>
#include <ESP32Servo.h>
#include <DHT11.h>

Ticker timer; // Create a Ticker object

// Initialize the LCD
LiquidCrystal lcd(12, 13, 14, 27, 26, 25); // Pins for RS, E, D4, D5, D6, D7

// Initialize servo motor
const int servoPin = 20;
Servo myServo;

// Initialize Gas sensor
const int gasSensorPin = 34;
const int threshold = 300; // is the start gas sensor value to alarm

// Initialize Temperature sensor
const int DHTPin = 4;
DHT11 dht11;

// Initialize Buzzer 
const int buzzerPin = 6;

// Initialize IR sensor
const int IRPin = 8

const byte ROWS = 4; // Four rows
const byte COLS = 4; // Four columns
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};
byte rowPins[ROWS] = {19, 18, 5, 17}; // Connect to the row pinouts of the keypad
byte colPins[COLS] = {16, 4, 0, 2};    // Connect to the column pinouts of the keypad

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);
String pass = "156879";

Preferences preferences; // Create a Preferences object

void deleteOTPPassword() {
  preferences.begin("passwords", false);
  preferences.remove("password"); // Remove the password from preferences
  preferences.end();
  Serial.println("Password deleted!");
}

void get_password(){
  String enteredPass = "";
  lcd.clear(); // Clear the LCD
  lcd.setCursor(0, 0);
  lcd.print("Enter password:");
  lcd.setCursor(0, 1);
  int passIndex = 0; // Variable to keep track of the current index of the entered password
  while(true){
    // Read from keypad
    char key = keypad.getKey();
    
    if (key && passIndex < pass.length()) {
      Serial.println(key);
      if (key == 'C' && passIndex > 0) {
        // Clear the last entered key
        lcd.setCursor(passIndex - 1, 1); // Set cursor to the previous position
        lcd.print(' '); // Clear the character
        lcd.setCursor(passIndex - 1, 1);
        enteredPass.remove(enteredPass.length() - 1); // Remove the last character from the entered password
        passIndex--; // Decrement the index of the entered password
      } else if (key != 'C') {
        // Append the key to the entered password
        enteredPass += key;
        lcd.print('*'); // Print * to represent each entered character
        passIndex++; // Increment the index of the entered password
      }
    }
    
    // Check if the entered password matches the predefined one
    if (enteredPass == pass) {
      lcd.clear(); // Clear the LCD
      lcd.setCursor(0, 0); // Set cursor to the first row, first column
      lcd.print("Correct pass"); // Display message for correct password
      delay(2000); // Wait for 2 seconds
      lcd.clear(); // Clear the LCD
      return;
    }
    else if(enteredPass.length() == pass.length() && enteredPass!=pass){
      lcd.clear(); // Clear the LCD
      lcd.setCursor(0, 0); // Set cursor to the first row, first column
      lcd.print("Invalid pass"); // Display message for correct password
      delay(2000); // Wait for 2 seconds
      lcd.clear(); // Clear the LCD
      return;
    }
    
    delay(100); // Slight delay to debounce the keypad

  }
}

// Function to handle the password received from the broker
void OTP_pass(String password) {
  preferences.begin("passwords", false);
  preferences.putString("password", password); // Save the password in preferences
  preferences.end();
  Serial.println("Password stored successfully!");

  // Set up the timer to delete the password after 15 minutes (900,000 milliseconds)
  timer.attach(900000, deleteOTPPassword); // Attach the deletePassword function to run after 15 minutes
}

// Function to set the servo angle
void setServoAngle(int angle) {
  // Ensure the angle is within the valid range
  if (angle < 0) angle = 0;
  if (angle > 180) angle = 180;

  // Write the angle to the servo
  myServo.write(angle);
}

// Function to check if gas is detected
bool isGasDetected() {
  // Read the analog value from the MQ-5 sensor
  int sensorValue = analogRead(mq5Pin);
  
  // Print the sensor value for debugging
  Serial.print("Sensor value: ");
  Serial.println(sensorValue);
  
  // Compare the sensor value with the threshold
  if (sensorValue > threshold) {
    buzerrON();
    return true;
  } else {
    return false;
  }
}

// Function to get temperature and humidity
void getTemperatureAndHumidity(float &temperature, float &humidity) {
  // Read temperature and humidity
  int chk = dht11.read(DHTPin, &temperature, &humidity, NULL);
  
  // Check if the Reading failed
  if (chk != DHTLIB_OK) {
    temperature = -1;  // Indicate failure with a specific value
    humidity = -1;     // Indicate failure with a specific value
  }
}

void buzerrON(){
  digitalWrite(buzzerPin, HIGH);
}
void buzerrOFF(){
  digitalWrite(buzzerPin, LOW);
}

bool isDoorOpen(){
  if(digitalRead(IRPin) == 1){
    // Door Closed 
    return false;
  }else{
    return true;
  }
}

void setup() {
  Serial.begin(115200);.

  // Initialize the Servo motor
  myServo.attach(servoPin);

  pinMode(buzzerPin, OUTPUT);

  pinMode(IRPin, INPUT);

  pinMode(gasSensorPin, INPUT);

  lcd.begin(16, 2); // Initialize the LCD with 16 columns and 2 rows
  lcd.clear(); // Clear the LCD
  
  preferences.begin("passwords", false); // Begin preferences with the namespace "passwords"

  // Retrieve and display the stored password (if any)
  String storedPass = preferences.getString("password", "No password stored");
  Serial.println("Stored Password: " + storedPass);
}

void loop() {
  char key = keypad.getKey();
  
  if (key) {
    get_password();
    Serial.println("End get pass");
    pinMode(21, OUTPUT);
    digitalWrite(21, HIGH);
    delay(1000);
    digitalWrite(21, LOW);
  }
  }