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

// กำหนดขา Pin
#define DHTPIN 19
#define DHTTYPE DHT22
#define RELAY1 12
#define RELAY2 13
#define RELAY3 14
#define TRIG_PIN 5
#define ECHO_PIN 4
#define PIR_PIN 15
#define LED_PIN 27

// ประกาศตัวแปรอุปกรณ์
LiquidCrystal_I2C lcd(0x27, 20, 4); 
RTC_DS1307 rtc;
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200);

  pinMode(RELAY1, OUTPUT);
  pinMode(RELAY2, OUTPUT);
  pinMode(RELAY3, OUTPUT);
  pinMode(LED_PIN, OUTPUT);
  
  digitalWrite(RELAY1, LOW); 
  digitalWrite(RELAY2, LOW);
  digitalWrite(RELAY3, LOW);
  digitalWrite(LED_PIN, LOW);

  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(PIR_PIN, INPUT);

  lcd.init();
  lcd.backlight();
  dht.begin();
  
  if (!rtc.begin()) {
    while (1);
  }
}

void loop() { // เริ่มต้นฟังก์ชัน loop
  DateTime now = rtc.now();
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  int pirStatus = digitalRead(PIR_PIN);

  // คำนวณระยะทาง Ultrasonic
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  long duration = pulseIn(ECHO_PIN, HIGH);
  float distanceCm = duration * 0.034 / 2;

  // เงื่อนไข LED จาก PIR
  if (pirStatus == HIGH) {
    digitalWrite(LED_PIN, HIGH);
  } else {
    digitalWrite(LED_PIN, LOW);
  }

  // จัดการสถานะ Relay
  String r1_st, r2_st, r3_st;

  if (t > 30) { digitalWrite(RELAY1, HIGH); r1_st = "ON "; } 
  else { digitalWrite(RELAY1, LOW); r1_st = "OFF"; }

  if (h < 50) { digitalWrite(RELAY2, HIGH); r2_st = "ON "; } 
  else { digitalWrite(RELAY2, LOW); r2_st = "OFF"; }

  if (distanceCm < 30) { digitalWrite(RELAY3, HIGH); r3_st = "ON "; } 
  else { digitalWrite(RELAY3, LOW); r3_st = "OFF"; }

  // แสดงผลบนจอ LCD 2004
  lcd.setCursor(0, 0);
  char timeBuf[20];
  sprintf(timeBuf, "Time: %02d:%02d:%02d", now.hour(), now.minute(), now.second());
  lcd.print(timeBuf);

  lcd.setCursor(0, 1);
  lcd.print("Dist: "); 
  lcd.print(distanceCm, 1); 
  lcd.print(" cm.      ");

  lcd.setCursor(0, 2);
  lcd.print("T:"); lcd.print(t, 1); lcd.print("C  H:"); lcd.print(h, 1); lcd.print("%   ");

  lcd.setCursor(0, 3);
  lcd.print("R1:"); lcd.print(r1_st);
  lcd.print(" R2:"); lcd.print(r2_st);
  lcd.print(" R3:"); lcd.print(r3_st);

  delay(500); 
} // ปิดฟังก์ชัน loop (จุดที่เคย Error)