#define BLYNK_TEMPLATE_ID "TMPL3I2IanZ2T"
#define BLYNK_TEMPLATE_NAME "EmbedX Smart Greenhouse Management System"
#define BLYNK_AUTH_TOKEN "KuahdvzJoEp3JOzDULw6JkEJbjYPA8mZ"

#define BLYNK_PRINT Serial
#include <WiFi.h>
#include <BlynkSimpleEsp32.h>
#include <HX711.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>

char ssid[] = "Wokwi-GUEST";
char pass[] = "";
char auth[] = "KuahdvzJoEp3JOzDULw6JkEJbjYPA8mZ";

#define LED 2
#define GAS_SENSOR 34
#define LOADCELL_DOUT_PIN 21
#define LOADCELL_SCK_PIN 22
#define RELAY_PIN 4
#define DHT22PIN 15
#define DHTTYPE DHT22

#define I2C_ADDR 0x27
#define LCD_COLUMNS 16
#define LCD_ROWS 2

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_ROWS);
HX711 scale;
DHT dht(DHT22PIN, DHTTYPE);
BlynkTimer timer;

int gasValue;
int screen = 0;
float temp, hum;
float weightKg;

// ✅ Your original calibration logic restored
float calibration_factor = 419.8;

const int temp_threshold = 29;

void setup() {
  pinMode(LED, OUTPUT);
  pinMode(RELAY_PIN, OUTPUT);
  digitalWrite(RELAY_PIN, LOW);

  Serial.begin(115200);
  Serial.println("ESP32 Multi-Sensor Start");

  Wire.begin(5, 23);
  lcd.init();
  lcd.backlight();

  lcd.setCursor(0, 0);
  lcd.print("System Starting");
  delay(1500);
  lcd.clear();

  // ✅ Original HX711 logic restored
  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
  scale.set_scale(calibration_factor);
  scale.tare();

  dht.begin();

  lcd.setCursor(0, 0);
  lcd.print("Connecting...");
  Blynk.begin(auth, ssid, pass);

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Connected!");
  delay(1000);

  timer.setInterval(3000, sendToBlynk);
}

void loop() {
  Blynk.run();
  timer.run();

  hum = dht.readHumidity();
  temp = dht.readTemperature();

  // Gas logic unchanged
  int rawGas = analogRead(GAS_SENSOR);
  gasValue = map(rawGas, 0, 4095, 0, 4040);

  if (gasValue < 0) gasValue = 0;
  if (gasValue > 4040) gasValue = 4040;

  if (isnan(hum) || isnan(temp)) {
    Serial.println("DHT Error!");
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("DHT Error");
    delay(2000);
    return;
  }

  // ✅ Original weight logic restored
  if (scale.is_ready()) {

    weightKg = scale.get_units(10);   // average of 10 readings

    if (weightKg < 0.02) weightKg = 0;
    if (weightKg < 0) weightKg = 0;
    if (weightKg > 5) weightKg = 5;

  } else {
    Serial.println("Scale not ready");
    weightKg = 0;
  }

  Serial.printf("Temp: %.1f Hum: %.1f Gas: %d Weight: %.2f\n",
                temp, hum, gasValue, weightKg);

  // LED logic unchanged
  if (temp > temp_threshold) {
    digitalWrite(LED, HIGH);
  } else {
    digitalWrite(LED, LOW);
  }

  // Relay logic unchanged
  if (temp > temp_threshold) {
    digitalWrite(RELAY_PIN, HIGH);
  } else {
    digitalWrite(RELAY_PIN, LOW);
  }

  // LCD display unchanged
  lcd.clear();

  if (screen == 0) {
    lcd.setCursor(0, 0);
    lcd.print("Temp:");
    lcd.print(temp, 1);
    lcd.print((char)223);
    lcd.print("C");

    lcd.setCursor(0, 1);
    lcd.print("Hum:");
    lcd.print(hum, 0);
    lcd.print("%");

  } else {
    lcd.setCursor(0, 0);
    lcd.print("Gas:");
    lcd.print(gasValue);

    lcd.setCursor(0, 1);
    lcd.print("Weight:");
    lcd.print(weightKg, 1);
    lcd.print("kg");
  }

  screen = (screen + 1) % 2;
  delay(1500);
}

// Blynk send logic unchanged
void sendToBlynk() {
  Blynk.virtualWrite(V0, temp);
  Blynk.virtualWrite(V1, hum);
  Blynk.virtualWrite(V2, weightKg);
  Blynk.virtualWrite(V3, gasValue);
}

// Manual relay control
BLYNK_WRITE(V4) {
  int fanState = param.asInt();
  digitalWrite(RELAY_PIN, fanState);
}