#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>

// Definisi PIN Sensor
#define DHTPIN 2
#define DHTTYPE DHT22
#define TMP_PIN A1
#define MQ135_PIN A2

// Inisialisasi Library
DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  // Inisialisasi LCD & DHT
  lcd.init();
  lcd.backlight();
  dht.begin();
  
  // Setup Pin Mode Sensor Analog
  pinMode(TMP_PIN, INPUT);
  pinMode(MQ135_PIN, INPUT);

  // Tampilan Awal (Booting)
  lcd.setCursor(0, 0);
  lcd.print("Menginisialisasi");
  lcd.setCursor(0, 1);
  lcd.print("Sistem Sensor...");
  delay(2000);
  lcd.clear();
}

void loop() {
  // --- 1. MEMBACA DATA SEMUA SENSOR ---
  
  // Baca DHT22
  float humDHT = dht.readHumidity();
  float tempDHT = dht.readTemperature();

  // Baca TMP36 (Sensor Suhu Analog)
  int tmpRaw = analogRead(TMP_PIN);
  float voltage = tmpRaw * (5.0 / 1023.0);
  float tempAnalog = (voltage - 0.5) * 100.0; // Rumus konversi TMP36 ke Celcius

  // Baca Sensor Gas MQ-135
  int nilaiGas = analogRead(MQ135_PIN);


  // --- 2. MENAMPILKAN DATA DI LCD (Sistem Halaman bergantian) ---

  // HALAMAN 1: Menampilkan Data Suhu (DHT22 vs TMP36)
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("T.DHT22 : ");
  if (isnan(tempDHT)) {
    lcd.print("Error");
  } else {
    lcd.print(tempDHT, 1);
    lcd.print((char)223); lcd.print("C"); // Simbol derajat
  }

  lcd.setCursor(0, 1);
  lcd.print("T.Analg : ");
  lcd.print(tempAnalog, 1);
  lcd.print((char)223); lcd.print("C");
  
  delay(3000); // Tampilkan Halaman 1 selama 3 detik


  // HALAMAN 2: Menampilkan Kelembapan & Kadar Gas
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Lembab  : ");
  if (isnan(humDHT)) {
    lcd.print("Error");
  } else {
    lcd.print(humDHT, 1);
    lcd.print("%");
  }

  lcd.setCursor(0, 1);
  lcd.print("Gas/PPM : ");
  lcd.print(nilaiGas);
  
  // Keterangan kondisi gas singkat
  if (nilaiGas < 300) {
    lcd.print(" (Aman)");
  } else if (nilaiGas < 600) {
    lcd.print(" (Waspada)");
  } else {
    lcd.print(" (Bahaya)");
  }

  delay(3000); // Tampilkan Halaman 2 selama 3 detik
}