// ============================================================
//  SISTEM MONITORING SUHU & KELEMBABAN RUANG KELAS
//  Hardware : ESP32-C3 DevKitM-1 + DHT22 + LCD 16x2 I2C
//  Author   : Dimas Nugroho (NIM: 23171065005)
//  Institusi: ITBU Jakarta
//  Simulasi : https://wokwi.com
// ============================================================

#include <WiFi.h>              // ✅ Ganti dari ESP8266WiFi.h
#include <WiFiClientSecure.h>
#include <Wire.h>              // ✅ Wajib untuk I2C (LCD)
#include <DHTesp.h>
#include <LiquidCrystal_I2C.h>

// ========================== CONFIG WI-FI ==========================
const char* ssid     = "Wokwi-GUEST";
const char* password = "";

// ======================== CONFIG TELEGRAM =========================
const String BOT_TOKEN = "7316018385:AAFAUR3-qhJ1ZQNDDgvSbRTLO9X1UWbkRMM";
const String CHAT_ID   = "303031334";

// ========================= KONFIGURASI PIN =============================
#define DHT_PIN   4   // GPIO4  → Pin DATA sensor DHT22
#define LED_RED   5   // GPIO5  → LED merah (indikator tidak normal)
#define LED_GREEN 6   // GPIO6  → LED hijau (indikator normal)

#define I2C_SDA   2
#define I2C_SCL   1 

// ========================= THRESHOLD SUHU ==============================
#define SUHU_MAX       30.0   // Suhu terlalu panas (°C)
#define SUHU_MIN       18.0   // Suhu terlalu dingin (°C)
#define KELEMBABAN_MAX 80.0   // Kelembaban terlalu tinggi (%)

// ====================== INISIALISASI OBJEK ============================
DHTesp dht;
LiquidCrystal_I2C lcd(0x27, 16, 2);  // Alamat I2C LCD = 0x27

// ========================= VARIABEL GLOBAL ============================
unsigned long waktuCekTerakhir   = 0;
unsigned long waktuKirimTerakhir = 0;
const long    INTERVAL_CEK       = 5000;   // Baca sensor setiap 5 detik
const long    INTERVAL_KIRIM     = 60000;  // Kirim status tiap 1 menit
bool          statusTerakhirNormal = true;

// ======================================================================
void setup() {
  Serial.begin(115200);
  delay(500);

  // ✅ Inisialisasi I2C dengan pin eksplisit untuk ESP32-C3
  Wire.begin(I2C_SDA, I2C_SCL);

  // Inisialisasi pin LED
  pinMode(LED_RED,   OUTPUT);
  pinMode(LED_GREEN, OUTPUT);
  digitalWrite(LED_RED,   LOW);
  digitalWrite(LED_GREEN, LOW);

  // Inisialisasi sensor DHT22
  dht.setup(DHT_PIN, DHTesp::DHT22);
  Serial.println("Sensor DHT22 siap...");

  // Inisialisasi LCD
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Sistem Monitoring");
  lcd.setCursor(0, 1);
  lcd.print("Ruang Kelas IoT");
  delay(2000);
  lcd.clear();

  // Koneksi Wi-Fi
  lcd.setCursor(0, 0);
  lcd.print("Konek WiFi...");
  Serial.print("Menghubungkan ke WiFi: ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);
  int percobaan = 0;
  while (WiFi.status() != WL_CONNECTED && percobaan < 20) {
    delay(500);
    Serial.print(".");
    percobaan++;
  }

  if (WiFi.status() == WL_CONNECTED) {
    Serial.println("\nWiFi Terhubung!");
    Serial.print("IP Address: ");
    Serial.println(WiFi.localIP());
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("WiFi Terhubung!");
    lcd.setCursor(0, 1);
    lcd.print(WiFi.localIP());
    delay(2000);

    kirimTelegram("*Sistem Monitoring Aktif!*\nMonitoring suhu ruang kelas telah dimulai.\nThreshold: " + String(SUHU_MIN) + "C - " + String(SUHU_MAX) + "C");
  } else {
    Serial.println("\nGagal konek WiFi. Mode Offline.");
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("WiFi Gagal!");
    lcd.setCursor(0, 1);
    lcd.print("Mode Offline");
    delay(2000);
  }

  lcd.clear();
}

// ======================================================================
void loop() {
  unsigned long waktuSekarang = millis();

  // ---- Baca sensor setiap INTERVAL_CEK ----
  if (waktuSekarang - waktuCekTerakhir >= INTERVAL_CEK) {
    waktuCekTerakhir = waktuSekarang;

    float suhu       = dht.getTemperature();
    float kelembaban = dht.getHumidity();

    if (isnan(suhu) || isnan(kelembaban)) {
      Serial.println("ERROR: Gagal membaca sensor DHT22!");
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Sensor Error!");
      lcd.setCursor(0, 1);
      lcd.print("Cek koneksi DHT");
      return;
    }

    Serial.println("----------------------------");
    Serial.print("Suhu       : "); Serial.print(suhu);       Serial.println(" C");
    Serial.print("Kelembaban : "); Serial.print(kelembaban); Serial.println(" %RH");

    lcd.setCursor(0, 0);
    lcd.print("Suhu: ");
    lcd.print(suhu, 1);
    lcd.print((char)223);
    lcd.print("C   ");

    lcd.setCursor(0, 1);
    lcd.print("Lembab: ");
    lcd.print(kelembaban, 1);
    lcd.print("%   ");

    bool kondisiNormal = (suhu >= SUHU_MIN && suhu <= SUHU_MAX && kelembaban <= KELEMBABAN_MAX);

    if (kondisiNormal) {
      digitalWrite(LED_GREEN, HIGH);
      digitalWrite(LED_RED,   LOW);
      Serial.println(">>> STATUS: NORMAL");
    } else {
      digitalWrite(LED_GREEN, LOW);
      digitalWrite(LED_RED,   HIGH);
      Serial.println(">>> STATUS: TIDAK NORMAL - PERINGATAN!");
    }

    if (!kondisiNormal && statusTerakhirNormal) {
      String pesan = "PERINGATAN RUANG KELAS!\n";
      if (suhu > SUHU_MAX)
        pesan += "Suhu TERLALU PANAS: " + String(suhu, 1) + "C (Max: " + String(SUHU_MAX) + "C)\n";
      else if (suhu < SUHU_MIN)
        pesan += "Suhu TERLALU DINGIN: " + String(suhu, 1) + "C (Min: " + String(SUHU_MIN) + "C)\n";
      if (kelembaban > KELEMBABAN_MAX)
        pesan += "Kelembaban TERLALU TINGGI: " + String(kelembaban, 1) + "% (Max: " + String(KELEMBABAN_MAX) + "%)\n";
      pesan += "Segera periksa kondisi ruangan!";
      kirimTelegram(pesan);
      statusTerakhirNormal = false;
    }

    if (kondisiNormal && !statusTerakhirNormal) {
      String pesan = "Kondisi Ruang Kelas Normal\n";
      pesan += "Suhu: " + String(suhu, 1) + "C\n";
      pesan += "Kelembaban: " + String(kelembaban, 1) + "%\n";
      pesan += "Ruangan kembali dalam kondisi ideal.";
      kirimTelegram(pesan);
      statusTerakhirNormal = true;
    }
  }

  // ---- Kirim laporan berkala setiap INTERVAL_KIRIM ----
  if (waktuSekarang - waktuKirimTerakhir >= INTERVAL_KIRIM && waktuKirimTerakhir != 0) {
    waktuKirimTerakhir = waktuSekarang;

    float suhu       = dht.getTemperature();
    float kelembaban = dht.getHumidity();

    if (!isnan(suhu) && !isnan(kelembaban)) {
      String pesan = "Laporan Berkala Ruang Kelas\n";
      pesan += "Suhu       : " + String(suhu, 1) + " C\n";
      pesan += "Kelembaban : " + String(kelembaban, 1) + " %RH\n";
      pesan += "Status WiFi: Terhubung\n";
      bool normal = (suhu >= SUHU_MIN && suhu <= SUHU_MAX);
      pesan += normal ? "Kondisi: NORMAL" : "Kondisi: PERIKSA!";
      kirimTelegram(pesan);
    }
  }

  if (waktuKirimTerakhir == 0) {
    waktuKirimTerakhir = millis();
  }
}

// ======================================================================
//  FUNGSI: Kirim pesan ke Bot Telegram
// ======================================================================
void kirimTelegram(String pesan) {
  if (WiFi.status() != WL_CONNECTED) {
    Serial.println("WiFi tidak terhubung. Notifikasi Telegram dibatalkan.");
    return;
  }

  WiFiClientSecure klien;
  klien.setInsecure();

  Serial.println("Mengirim ke Telegram...");

  if (klien.connect("api.telegram.org", 443)) {
    String url = "/bot" + BOT_TOKEN + "/sendMessage";
    String payload = "{\"chat_id\":\"" + CHAT_ID + "\","
                     "\"text\":\"" + pesan + "\","
                     "\"parse_mode\":\"Markdown\"}";

    klien.println("POST " + url + " HTTP/1.1");
    klien.println("Host: api.telegram.org");
    klien.println("Content-Type: application/json");
    klien.println("Content-Length: " + String(payload.length()));
    klien.println("Connection: close");
    klien.println();
    klien.println(payload);

    unsigned long batasWaktu = millis() + 5000;
    while (klien.connected() && millis() < batasWaktu) {
      if (klien.available()) {
        String baris = klien.readStringUntil('\n');
        if (baris.indexOf("\"ok\":true") > 0) {
          Serial.println("Pesan Telegram berhasil dikirim!");
          break;
        }
      }
    }
    klien.stop();
  } else {
    Serial.println("Gagal terkoneksi ke api.telegram.org");
  }
}