#include <LCD_I2C.h>
#include <DHT.h>

LCD_I2C lcd(0x27, 20, 4);

#define DHTPIN1 26
#define DHTTYPE1 DHT22

#define DHTPIN2 25
#define DHTTYPE2 DHT22

#define DHTPIN3 14
#define DHTTYPE3 DHT22

DHT dht1(DHTPIN1,DHTTYPE1);
DHT dht2(DHTPIN2,DHTTYPE2);
DHT dht3(DHTPIN3,DHTTYPE3);
int relay1 = 18;
int relay2 = 19;
int relay3 = 23;

void setup() {

  pinMode(relay1,OUTPUT);
  pinMode(relay2,OUTPUT);
  pinMode(relay3,OUTPUT);

  dht1.begin();
  dht2.begin();
  dht3.begin();
  lcd.begin();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("T1:");
  lcd.setCursor(10, 0);
  lcd.print("H1:");
  lcd.setCursor(0, 1);
  lcd.print("T2:");
  lcd.setCursor(10, 1);
  lcd.print("H2:");
  lcd.setCursor(0, 2);
  lcd.print("T3:");
  lcd.setCursor(10, 2);
  lcd.print("H3:");

}

void loop() {
  delay(2000);
  float h1 = dht1.readHumidity();
  float t1 = dht1.readTemperature();
  
  float h2 = dht2.readHumidity();
  float t2 = dht2.readTemperature();

  float h3 = dht3.readHumidity();
  float t3 = dht3.readTemperature();
  
  if (isnan(h1) || isnan(t1)) {
    lcd.println("Failed to read from DHT1 sensor!");
  }
  else
  {
  lcd.setCursor(0, 0);
  lcd.print("T1: ");
  lcd.setCursor(3, 0);
  lcd.print(t1,1);
  lcd.print(" C ");
  lcd.setCursor(10, 0);
  lcd.print("H1:");
  lcd.setCursor(13, 0);
  lcd.print(h1,1);
  lcd.print(" % ");
  if (t1 >= 20){
    digitalWrite(relay1, HIGH);
  }
  else{
    digitalWrite(relay1, LOW);
  }
  }
  if (isnan(h2) || isnan(t2)) {
    lcd.println("Failed to read from DHT2 sensor!");
  }
  else
  {
  lcd.setCursor(0, 1);
  lcd.print("T2:");
  lcd.setCursor(3, 1);
  lcd.print(t2,1);
  lcd.print(" C ");
  lcd.setCursor(10, 1);
  lcd.print("H2:");
  lcd.setCursor(13, 1);
  lcd.print(h2,1);
  lcd.print(" % ");
  if (t2 >= 30){
    digitalWrite(relay2, HIGH);
  }
  else{
    digitalWrite(relay2, LOW);
  }
  }
  if (isnan(h3) || isnan(t3)) {
    lcd.println("Failed to read from DHT2 sensor!");
  }
  else
  {
  lcd.setCursor(0, 2);
  lcd.print("T3:");
  lcd.setCursor(3, 2);
  lcd.print(t3,1);
  lcd.print(" C ");
  lcd.setCursor(10, 2);
  lcd.print("H3:");
  lcd.setCursor(13, 2);
  lcd.print(h3,1);
  lcd.print(" % ");
  if (t3 >= 35){
    digitalWrite(relay3, HIGH);
  }
  else{
    digitalWrite(relay3, LOW);
  }
  }
}