#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>
#include <ESP32Servo.h>
#include <MFRC522.h>
#include <SPI.h>
#include "RTClib.h"

// --- Configuration Pins ---
#define LIGHT_PIN 4
#define FAN_PIN 15
#define POT_PIN 34
#define SERVO_PIN 17 
#define BUZZER_PIN 2
#define RST_PIN 0
#define SS_PIN 5

// --- Timezone Offset ---
#define TIME_OFFSET 19800 

// --- Objects ---
LiquidCrystal_I2C lcd(0x27, 16, 2);
Servo myServo;
MFRC522 rfid(SS_PIN, RST_PIN);
RTC_DS1307 rtc;

// --- Keypad Setup ---
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] = {13, 12, 14, 27}; 
byte colPins[COLS] = {26, 25, 33, 32}; 
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// --- Variables ---
String inputCode = "";
const String masterCode = "1234";
bool lightState = false;
bool fanState = false;
bool autoTriggered = false; 

void setup() {
  Serial.begin(115200);
  SPI.begin();
  rfid.PCD_Init();
  
  lcd.init();
  lcd.backlight();
  
  if (!rtc.begin()) {
    Serial.println("Couldn't find RTC");
  }

  DateTime compileTime = DateTime(F(__DATE__), F(__TIME__));
  rtc.adjust(DateTime(compileTime.unixtime() + TIME_OFFSET));

  pinMode(LIGHT_PIN, OUTPUT);
  pinMode(FAN_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  
  myServo.attach(SERVO_PIN);
  myServo.write(0); 

  lcd.setCursor(0,0);
  lcd.print("SMART HOME START");
  delay(1500);
  lcd.clear();
}

void unlockDoor() {
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("ACCESS GRANTED");
  
  // Single beep for success
  digitalWrite(BUZZER_PIN, HIGH);
  delay(300);
  digitalWrite(BUZZER_PIN, LOW);
  
  myServo.write(90);
  delay(3000);
  myServo.write(0);
  lcd.clear();
}

void wrongPasswordAlert() {
  lcd.setCursor(0,0);
  lcd.print("INVALID CODE!   ");
  
  // Two short beeps for failure
  digitalWrite(BUZZER_PIN, HIGH);
  delay(100);
  digitalWrite(BUZZER_PIN, LOW);
  delay(100);
  digitalWrite(BUZZER_PIN, HIGH);
  delay(100);
  digitalWrite(BUZZER_PIN, LOW);
  
  delay(1000);
  lcd.clear();
}

void loop() {
  DateTime now = rtc.now();

  // --- 1. Automation (Trigger at 4:00 PM / 16:00) ---
  if (now.hour() >= 16 && !autoTriggered) {
    lightState = true;
    fanState = true;
    digitalWrite(LIGHT_PIN, HIGH);
    digitalWrite(FAN_PIN, HIGH);
    autoTriggered = true; 
  }
  
  if (now.hour() == 0) autoTriggered = false;

  // --- 2. Manual Controls ---
  char key = keypad.getKey();
  if (key) {
    if (key == 'A') {
      lightState = !lightState;
      digitalWrite(LIGHT_PIN, lightState);
    } 
    else if (key == 'B') {
      fanState = !fanState;
      digitalWrite(FAN_PIN, fanState);
    }
    else if (key == '#') {
      if (inputCode == masterCode) {
        unlockDoor();
      } else {
        wrongPasswordAlert(); // Updated to beep on failure
      }
      inputCode = "";
    } 
    else if (isdigit(key)) {
      inputCode += key;
    }
  }

  // --- 3. RFID Check ---
  if (rfid.PICC_IsNewCardPresent() && rfid.PICC_ReadCardSerial()) {
    unlockDoor();
    rfid.PICC_HaltA();
  }

  // --- 4. LCD Display ---
  lcd.setCursor(0, 0);
  if (inputCode == "") {
    char timeStr[17];
    sprintf(timeStr, "%02d:%02d:%02d L:%d F:%d", 
            now.hour(), now.minute(), now.second(), 
            lightState, fanState);
    lcd.print(timeStr);
  } else {
    lcd.print("CODE: " + inputCode + "    ");
  }

  // Energy Meter (Row 1)
  int raw = analogRead(POT_PIN);
  float watts = (raw / 4095.0) * 500.0; 
  lcd.setCursor(0, 1);
  lcd.print("USAGE: ");
  lcd.print(watts, 1);
  lcd.print("W      ");
  
  delay(100);
}