#include <Arduino.h>
#include "HX711.h"
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// HX711 circuit wiring
const int LOADCELL_DOUT_PIN = 2;
const int LOADCELL_SCK_PIN = 0;

HX711 scale;

void calibrateScale();

// Known weight in grams for calibration
const float knownWeight = 5000;  // Change this to your known weight

void setup() {
  Serial.begin(115200);
  while (!Serial) {
    ; // Wait for serial port to connect
  }

  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
  scale.set_scale(0.424);
  calibrateScale();

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 10);
  // Display static text
  display.println("Testing");
  display.display(); 
}

void loop() {
  if (scale.is_ready()) {
    long reading = scale.get_units();
    Serial.print("HX711 reading: ");
    Serial.println(reading);

    display.clearDisplay();
    display.setCursor(0, 10);
    // Display static text
    display.print("Reading : ");
    display.println(reading);
    display.display();

  } else {
    Serial.println("HX711 not found.");
  }

  
  
}

// Calibration function
void calibrateScale() {
  float scaleFactor = 1.0;  // Initial scale factor

  // Set up the scale
  scale.set_scale();

  // Tare the scale to zero
  scale.tare();

  // Place the known weight on the scale and measure it
  Serial.println("Place the known weight on the scale.");

  while (Serial.peek() != '\n');

  float measuredWeight = scale.get_units(10); // Read the weight
  Serial.print("Measured weight: ");
  Serial.print(measuredWeight);
  Serial.println(" g");

  // Calculate the scale factor
  scaleFactor = measuredWeight / knownWeight;

  // Apply the scale factor to the HX711 instance
  scale.set_scale(scaleFactor);

  // Print the calibration factor for reference
  Serial.print("Calibration factor: ");
  Serial.println(scaleFactor);
}