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

// Sensor Pins
#define DHTPIN        4
#define DHTTYPE       DHT22
#define TRIG_PIN      5
#define ECHO_PIN      18
#define LDR_PIN       19
#define GAS_PIN       34
#define PIR_PIN       21

// Sensor Objects
DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16, 2); // I2C address might be 0x3F on some modules

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

    // Initialize LCD
      lcd.init();
        lcd.backlight();

          // Initialize Sensors
            dht.begin();
              pinMode(TRIG_PIN, OUTPUT);
                pinMode(ECHO_PIN, INPUT);
                  pinMode(LDR_PIN, INPUT);
                    pinMode(GAS_PIN, INPUT);
                      pinMode(PIR_PIN, INPUT);

                        lcd.setCursor(0, 0);
                          lcd.print("ESP32 Sensors");
                            delay(2000);
                              lcd.clear();
                              }

                              void loop() {
                                // DHT22
                                  float temp = dht.readTemperature();
                                    float humidity = dht.readHumidity();

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

                                                          // Digital LDR
                                                            bool isLight = digitalRead(LDR_PIN);

                                                              // Analog Gas Sensor
                                                                int gasValue = analogRead(GAS_PIN);

                                                                  // PIR Motion Sensor
                                                                    bool motionDetected = digitalRead(PIR_PIN);

                                                                      // Debugging via Serial Monitor
                                                                        Serial.println("----------");
                                                                          Serial.print("Temp: "); Serial.println(temp);
                                                                            Serial.print("Humidity: "); Serial.println(humidity);
                                                                              Serial.print("Distance: "); Serial.print(distance); Serial.println(" cm");
                                                                                Serial.print("Light: "); Serial.println(isLight ? "Bright" : "Dark");
                                                                                  Serial.print("Gas: "); Serial.println(gasValue);
                                                                                    Serial.print("Motion: "); Serial.println(motionDetected ? "YES" : "NO");

                                                                                      // Display on LCD
                                                                                        lcd.clear();
                                                                                          lcd.setCursor(0, 0);
                                                                                            lcd.print("T:"); lcd.print(temp, 1); lcd.print("C ");
                                                                                              lcd.print("H:"); lcd.print(humidity, 0);

                                                                                                lcd.setCursor(0, 1);
                                                                                                  if (motionDetected) {
                                                                                                      lcd.print("M:Yes ");
                                                                                                        } else {
                                                                                                            lcd.print("M:No  ");
                                                                                                              }

                                                                                                                lcd.print("L:"); lcd.print(isLight ? "Bright" : "Dark");

                                                                                                                  delay(2000); // Delay between readings
                                                                                                                  }