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

LiquidCrystal_I2C lcd(0x27, 16, 2);

#define DHTPIN 2     // Digital pin connected to the DHT sensor
#define DHTTYPE DHT11   // DHT 11
const int trigPin = 7; // Trigger Pin of Ultrasonic Sensor
const int echoPin = 6; // Echo Pin of Ultrasonic Sensor
int sensor = 4;              // the pin that the sensor is atteched to
int state = LOW;             // by default, no motion detected
int val = 0;
DHT dht(DHTPIN, DHTTYPE);
long duration;
int distance;
void setup()
{
  pinMode(A0, INPUT);
  Serial.begin(9600);
  lcd.init();
  lcd.backlight();
  dht.begin();
  pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
  pinMode(echoPin, INPUT); // Sets the echoPin as an Input
  lcd.clear();
}

void loop()
{
  // Reading temperature or humidity takes about 250 milliseconds!
  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
  float h = dht.readHumidity();
  // Read temperature as Celsius (the default)
  float t = dht.readTemperature();
  // Read temperature as Fahrenheit (isFahrenheit = true)
  float f = dht.readTemperature(true);

  // Check if any reads failed and exit early (to try again).
  if (isnan(h) || isnan(t) || isnan(f)) {
    Serial.println(F("Failed to read from DHT sensor!"));
    return;
  }

  int analogSensor = analogRead(A0);
  Serial.print("Gas: ");
  Serial.println(analogSensor);



  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = duration * 0.034 / 2;
  Serial.print("Distance: ");
  Serial.println(distance);

  float hif = dht.computeHeatIndex(f, h);
  float hic = dht.computeHeatIndex(t, h, false);

  Serial.print(F("Humidity: "));
  Serial.print(h);
  Serial.print(F("%  Temperature: "));
  Serial.print(t);
  Serial.print(F("°C "));
  Serial.print(f);
  Serial.print(F("°F  Heat index: "));
  Serial.print(hic);
  Serial.print(F("°C "));
  Serial.print(hif);
  Serial.println(F("°F"));

  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(t);
  lcd.print("*C");
  lcd.setCursor(0, 1);
  lcd.print("Humi: ");
  lcd.print(h);
  lcd.print("%");
  delay(2000);
  lcd.clear();
  delay(2000);
  lcd.print("Gas: ");
  lcd.print(analogSensor);
  delay(2000);
  lcd.clear();
  delay(2000);
  lcd.print("Distance: ");
  lcd.print(distance);
  delay(2000);
  lcd.clear();

  val = digitalRead(sensor);
  if (val == HIGH) {
    delay(100);
    if (state == LOW) {
      lcd.print("Motion detected! ");
      delay(2000);
      lcd.clear();
      Serial.println("Motion detected!");
      state = HIGH;
    }
  }
  else {
    delay(200);
    if (state == HIGH) {
      Serial.println("Motion stopped!");
      state = LOW;
      lcd.print("Motion stopped! ");
      delay(2000);
      lcd.clear();
    }
  }
}