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

#define DHTPIN 4
#define DHTTYPE DHT11
#define TRIG_PIN 5
#define ECHO_PIN 18

#define LIGHT_PIN 23

#define PIR_PIN 19


LiquidCrystal_I2C lcd (0x27, 16, 2); 
const char* ssid = "Wokwi-GUEST";
const char* password = "";
unsigned long myChannelNumber = 2597177;
const char* myWriteAPIKey = "RTMWEN8VLSD9R8T0";
WiFiClient client;

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

  dht.begin();

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

  
  pinMode(LIGHT_PIN, OUTPUT);

  
  pinMode(PIR_PIN, INPUT);

  
  Wire.begin(21, 22); 
  lcd.init();
  lcd.backlight();

  
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");

  
  ThingSpeak.begin(client);

  Serial.println("Setup complete");
}

void loop() {
  
  float h = dht.readHumidity();
  float t = dht.readTemperature();

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

  
  int pirState = digitalRead(PIR_PIN);

  
  if (t > 25) { // Fan ON if temperature > 25 degrees Celsius
    fanStatus = "ON";
  } else {
    fanStatus = "OFF";
  }

  
  String doorStatus;
  if (distance > 20 && distance < 40) {
    doorStatus = "DOOR OPEN";
  } else {
    doorStatus = "DOOR CLOSE";
  }


  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(t);
  lcd.print(" C");
  
  lcd.setCursor(0, 1);
  lcd.print("Fan:");
  lcd.print(fanStatus);

  if (pirState == HIGH) {
    lcd.setCursor(8, 1);
    lcd.print("MOTION:D"); // D for Detected
    digitalWrite(LIGHT_PIN, HIGH);
    Serial.println("People found in room, lights on");
  } else {
    lcd.setCursor(8, 1);
    lcd.print("MOTION:N"); // N for Not detected
    digitalWrite(LIGHT_PIN, LOW);
  }

  // Display door status on LCD
  lcd.setCursor(0, 2);
  lcd.print(doorStatus);

  // Print details to Serial Monitor
  Serial.print("Temperature: ");
  Serial.print(t);
  Serial.println(" C");
  
  Serial.print("Humidity: ");
  Serial.print(h);
  Serial.println(" %");

  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  if (pirState == HIGH) {
    Serial.println("Motion Detected: YES");
  } else {
    Serial.println("Motion Detected: NO");
  }

  Serial.print("Fan: ");
  Serial.println(fanStatus);

  Serial.print("Door: ");
  Serial.println(doorStatus);

  // Upload data to ThingSpeak
  if (WiFi.status() == WL_CONNECTED) {
    ThingSpeak.setField(1, t);
    ThingSpeak.setField(2, pirState);
    ThingSpeak.setField(3, doorStatus == "DOOR OPEN" ? 1 : 0);
    ThingSpeak.setField(4, distance);
    int x = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
    
    if (x == 200) {
      Serial.println("Channel Update Successful");
    } else {
      Serial.println("Problem Updating channel. HTTP error code " + String(x));
    }
  } else {
    Serial.println("WiFi not connected");
  }

  delay(2000); // Wait for 2 seconds before next loop
}