#include "HX711.h"
#include <LiquidCrystal.h>
#include <ArduinoJson.h>

// HX711 circuit wiring for 4 load cells
const int LOADCELL_DOUT_PIN_1 = 2;
const int LOADCELL_SCK_PIN_1 = 3;

const int LOADCELL_DOUT_PIN_2 = 4;
const int LOADCELL_SCK_PIN_2 = 5;

const int LOADCELL_DOUT_PIN_3 = 6;
const int LOADCELL_SCK_PIN_3 = 7;

const int LOADCELL_DOUT_PIN_4 = 8;
const int LOADCELL_SCK_PIN_4 = 9;

HX711 scale1;
HX711 scale2;
HX711 scale3;
HX711 scale4;

// LCD pin configuration
const int rs = 10, en = 11, d4 = 12, d5 = 13, d6 = A0, d7 = A1;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

void setup() {
  Serial.begin(9600);
  lcd.begin(16, 2);  // Initialize a 16x2 LCD
  lcd.print("Initializing...");

  scale1.begin(LOADCELL_DOUT_PIN_1, LOADCELL_SCK_PIN_1);
  scale2.begin(LOADCELL_DOUT_PIN_2, LOADCELL_SCK_PIN_2);
  scale3.begin(LOADCELL_DOUT_PIN_3, LOADCELL_SCK_PIN_3);
  scale4.begin(LOADCELL_DOUT_PIN_4, LOADCELL_SCK_PIN_4);

  lcd.clear();
  lcd.print("Ready");
}

void loop() {
  if (scale1.is_ready() && scale2.is_ready() && scale3.is_ready() && scale4.is_ready()) {
    long reading1 = scale1.read() / 2100.0 * 5000.0;
    long reading2 = scale2.read() / 2100.0 * 5000.0;
    long reading3 = scale3.read() / 2100.0 * 5000.0;
    long reading4 = scale4.read() / 2100.0 * 5000.0;

    long totalWeight = reading1 + reading2 + reading3 + reading4;
    float totalKg = totalWeight / 1000.0;  // Convert to kilograms

    // Create a JSON document
    StaticJsonDocument<200> doc;
    doc["Reading1"] = reading1;
    doc["Reading2"] = reading2;
    doc["Reading3"] = reading3;
    doc["Reading4"] = reading4;
    doc["TotalKg"] = totalKg;

    // Serialize the JSON document to a string
    String jsonString;
    serializeJson(doc, jsonString);

    // Print the JSON string to Serial Monitor
    Serial.println(jsonString);

    // Display the total weight on the LCD
    lcd.clear();
    lcd.print("Weight: ");
    lcd.print(totalKg);
    lcd.print(" kg");

  } else {
    Serial.println("One or more HX711 modules not found.");
    lcd.clear();
    lcd.print("Error: HX711");
  }
  delay(2000);
}