#include <Keypad.h>
#include <ESP32Servo.h>
#include <WiFi.h>
#include <PubSubClient.h>

// Wi-Fi credentials
const char* ssid = "Wokwi-GUEST";
const char* password = "iotappsec";

// MQTT broker details
const char* mqtt_server = "mqtt-dashboard.com";
const int mqtt_port = 8884; // Use non-encrypted MQTT port
const char* mqtt_client_id = "clientId-Yc21ABPqDs";
const char* mqtt_topic = "smartlock/status";

// Define keypad settings
const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};
byte rowPins[ROWS] = {21, 19, 18, 5};
byte colPins[COLS] = {17, 16, 4, 0};

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// Define servo
Servo doorLock;

// GPIO pins for LEDs and buzzer
const int greenLED = 26;
const int redLED = 27;
const int buzzer = 25;

// PIN and state variables
String correctPIN = "1234";
String enteredPIN = "";
bool doorUnlocked = false;
unsigned long lockTimeout = 5000; // 5 seconds
unsigned long unlockTime;

// Wi-Fi and MQTT clients
WiFiClient espClient;
PubSubClient client(espClient);

// Function prototypes
void reconnect();
void unlockDoor();
void lockDoor();
void incorrectPIN();
void playHarmony();
void playEvilTone();

void setup() {
  // Initialize servo
  doorLock.attach(23); // Servo connected to GPIO 23
  lockDoor();

  // Initialize LEDs and buzzer
  pinMode(greenLED, OUTPUT);
  pinMode(redLED, OUTPUT);
  pinMode(buzzer, OUTPUT);

  // Start serial communication
  Serial.begin(115200);

  // Connect to Wi-Fi
  Serial.println("Connecting to Wi-Fi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.print(".");
  }
  Serial.println("\nWi-Fi Connected!");

  // Setup MQTT
  client.setServer(mqtt_server, mqtt_port);
}

void loop() {
  // Ensure MQTT connection
  if (!client.connected()) {
    reconnect();
  }
  client.loop();

  // Handle keypad input
  char key = keypad.getKey();
  if (key) {
    Serial.println(key);
    if (key == '#') {
      // Submit the PIN
      if (enteredPIN == correctPIN) {
        unlockDoor();  // Unlock the door if the PIN is correct
        unlockTime = millis();
        client.publish(mqtt_topic, "Door Unlocked");
      } else {
        incorrectPIN();  // Trigger alarm if the PIN is incorrect
        client.publish(mqtt_topic, "Incorrect PIN");
      }
      enteredPIN = ""; // Reset the entered PIN
    } else if (key == '*') {
      // Clear the entered PIN
      enteredPIN = "";
      Serial.println("PIN cleared");
    } else {
      // Append the pressed key to the entered PIN
      enteredPIN += key;
    }
  }

  // Auto-lock the door after timeout
  if (doorUnlocked && (millis() - unlockTime > lockTimeout)) {
    lockDoor();
    client.publish(mqtt_topic, "Door Locked");
  }
}

void reconnect() {
  // Attempt to reconnect to MQTT
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    if (client.connect("ESP32Client")) {
      Serial.println("connected");
      client.publish(mqtt_topic, "Device Connected");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void unlockDoor() {
  Serial.println("Door Unlocked!");
  doorLock.write(90); // Rotate servo to unlock position
  digitalWrite(greenLED, HIGH); // Turn on green LED
  digitalWrite(redLED, LOW); // Turn off red LED
  playHarmony(); // Play harmony sound for correct PIN
  doorUnlocked = true;
}

void lockDoor() {
  Serial.println("Door Locked!");
  doorLock.write(0); // Rotate servo to lock position
  digitalWrite(greenLED, LOW); // Turn off green LED
  digitalWrite(redLED, HIGH); // Turn on red LED
  doorUnlocked = false;
}

void incorrectPIN() {
  Serial.println("Incorrect PIN!");
  digitalWrite(redLED, HIGH);
  playEvilTone();
  delay(2000);
  digitalWrite(redLED, LOW);
}

void playHarmony() {
  tone(buzzer, 523, 300);
  delay(300);
  tone(buzzer, 659, 300);
  delay(300);
  tone(buzzer, 784, 300);
  delay(300);
  noTone(buzzer);
}

void playEvilTone() {
  tone(buzzer, 300, 500);
  delay(500);
  tone(buzzer, 250, 500);
  delay(500);
  tone(buzzer, 200, 500);
  delay(500);
  noTone(buzzer);
}