#include <WiFi.h>
#include <WiFiClientSecure.h>
#include <HTTPClient.h>
#include "time.h"
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <ESP32Servo.h>

#define PIR_PIN 14
#define LED_PIN 2
#define BUZZER_PIN 18
#define SERVO_PIN 25

const char* ssid = "Wokwi-GUEST";
const char* password = "";

String firebaseURL = "https://realtime-database-d6755-default-rtdb.firebaseio.com/intrusions.json";
String BOT_TOKEN   = "8053069579:AAG1mejRaKhKYsACOfPKwedwnism00rvo-A";
String CHAT_ID     = "7241417929";

const char* ntpServer = "pool.ntp.org";
const long gmtOffset_sec = 19800;
const int daylightOffset_sec = 0;

bool intrusionSent = false;

LiquidCrystal_I2C lcd(0x27, 16, 2);
Servo myServo;

// ===== GET DATE & TIME =====
String getFormattedDateTime() {
  struct tm timeinfo;
  if (!getLocalTime(&timeinfo)) {
    return "Time_Error";
  }

  char buffer[40];
  strftime(buffer, sizeof(buffer), "%d-%m-%Y %I:%M:%S %p", &timeinfo);
  return String(buffer);
}

// ===== FIREBASE =====
void sendToFirebase(String dateTime) {
  WiFiClientSecure client;
  client.setInsecure();

  HTTPClient https;
  https.begin(client, firebaseURL);
  https.addHeader("Content-Type", "application/json");

  String jsonData = "{\"status\":\"Intrusion Detected\",\"datetime\":\"" + dateTime + "\"}";

  int responseCode = https.POST(jsonData);

  Serial.print("Firebase Response: ");
  Serial.println(responseCode);

  https.end();
}

// ===== TELEGRAM =====
void sendTelegram(String dateTime) {

  WiFiClientSecure client;
  client.setInsecure();

  HTTPClient https;

  String message = "INTRUSION ALERT - " + dateTime;

  String encodedMessage = "";
  char c;
  char buf[4];

  for (int i = 0; i < message.length(); i++) {
    c = message.charAt(i);
    if (isalnum(c)) {
      encodedMessage += c;
    } else {
      sprintf(buf, "%%%02X", c);
      encodedMessage += buf;
    }
  }

  String url = "https://api.telegram.org/bot" + BOT_TOKEN +
               "/sendMessage?chat_id=" + CHAT_ID +
               "&text=" + encodedMessage;

  https.begin(client, url);
  int responseCode = https.GET();

  Serial.print("Telegram Response: ");
  Serial.println(responseCode);

  https.end();
}

// ===== SETUP =====
void setup() {

  Serial.begin(115200);

  pinMode(PIR_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);

  myServo.attach(SERVO_PIN);
  myServo.write(0);

  lcd.init();
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print("System Starting");

  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }

  configTime(gmtOffset_sec, daylightOffset_sec, ntpServer);
  delay(2000);

  lcd.clear();
  lcd.print("System Ready");
}

// ===== LOOP =====
void loop() {

  int motion = digitalRead(PIR_PIN);

  if (motion == HIGH && !intrusionSent) {

    String currentDateTime = getFormattedDateTime();

    Serial.println("Motion Detected!");
    Serial.println(currentDateTime);

    // 🔴 Activate Devices
    digitalWrite(LED_PIN, HIGH);
    digitalWrite(BUZZER_PIN, HIGH);
    myServo.write(90);

    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("INTRUSION!");
    lcd.setCursor(0,1);
    lcd.print(currentDateTime.substring(11)); // show time only

    sendToFirebase(currentDateTime);
    sendTelegram(currentDateTime);

    intrusionSent = true;
  }

  if (motion == LOW) {
    digitalWrite(LED_PIN, LOW);
    digitalWrite(BUZZER_PIN, LOW);
    myServo.write(0);
    intrusionSent = false;
  }

  delay(500);
}