#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <HX711.h>

// LCD initialization 
LiquidCrystal_I2C lcd(0x27, 16, 2);

// HX711 Pin assignments
const int DT1 = 3; // Data pin for HX711 #1
const int SCK1 = 2; // Clock pin for HX711 #1
const int DT2 = 5; // Data pin for HX711 #2
const int SCK2 = 4; // Clock pin for HX711 #2

HX711 scale1; // HX711 object for Part A
HX711 scale2; // HX711 object for Part B

// Button pin and potentiometer assignments
const int incrementButtonPin = 6; // Blue button
const int selectButtonPin = 7;    // Red button
const int pot = A0;               // Potentiometer pin

// A4988 Stepper Motor Driver pin assignments
const int stepPinA = 11; // STEP for motor A
const int dirPinA = 10;  // DIR for motor A
const int stepPinB = 9;  // STEP for motor B
const int dirPinB = 8;   // DIR for motor B

// Variables
int currentOption = 10;           // Initial option (10ml)
const int minOption = 10;         // Minimum value
const int maxOption = 700;        // Maximum value
const int stepSize = 5;           // Step increment after 5ml

bool isSelected = false;          // Flag to check if TOTAL is selected
bool partASelected = false;       // Flag for Part A
bool partBSelected = false;       // Flag for Part B
int totalSelected = 0;            // Store the selected TOTAL
const float density = 1.07;       // Density of the product (g/ml)

void setup() {
  pinMode(incrementButtonPin, INPUT_PULLUP);
  pinMode(selectButtonPin, INPUT_PULLUP);
  pinMode(pot, INPUT);

  // Initialize stepper motor driver pins
  pinMode(stepPinA, OUTPUT);
  pinMode(dirPinA, OUTPUT);
  pinMode(stepPinB, OUTPUT);
  pinMode(dirPinB, OUTPUT);

  // Initialize HX711 scales
  scale1.begin(DT1, SCK1); // Setup HX711 #1
  scale2.begin(DT2, SCK2); // Setup HX711 #2

  lcd.init();
  lcd.backlight();

  updateLCD(); // Display the initial selection screen
}

void loop() {
  // Read potentiometer value and map to ml range
  int potValue = analogRead(pot);  // Read potentiometer value (0-1023)
  currentOption = map(potValue, 0, 1023, minOption, maxOption);
  currentOption = (currentOption / stepSize) * stepSize;  // Round to nearest stepSize

  // Increment button logic
  if (digitalRead(incrementButtonPin) == LOW) {
    delay(200); // Debounce delay
    if (!isSelected) {
      incrementOption();   // Navigate TOTAL options
      updateLCD();         // Update the screen
    }
  }

  // Select button logic
  if (digitalRead(selectButtonPin) == LOW) {
    delay(200); // Debounce delay
    if (!isSelected) {
      totalSelected = currentOption; // Store the selected TOTAL
      isSelected = true;             // Mark as selected
      displayPartSelection("Part A"); // Show Part A selection
    } else if (!partASelected) {
      partASelected = true;          // Mark Part A as completed
      moveStepper(stepPinA, dirPinA, "Part A"); // Move stepper for Part A
      displayPartSelection("Part B"); // Show Part B selection
    } else if (!partBSelected) {
      partBSelected = true;          // Mark Part B as completed
      moveStepper(stepPinB, dirPinB, "Part B"); // Move stepper for Part B
      displayFinished();             // Show finished message
    } else {
      resetSelection();              // Restart the process
    }
  }

  delay(100); // Small delay to reduce flickering on LCD
}

// Increment through the dispensing options (this can be adjusted to work with the potentiometer)
void incrementOption() {
  currentOption += stepSize;
  if (currentOption > maxOption) {
    currentOption = minOption; // Wrap around to the minimum value (10ml)
  }
}

// Update LCD for navigating TOTAL options
void updateLCD() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Select Amount:");
  lcd.setCursor(0, 1);
  lcd.print(currentOption);
  lcd.print("ml");
}

// Display part selection (Part A or Part B)
void displayPartSelection(String part) {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Select:");
  lcd.setCursor(0, 1);
  lcd.print(part);
}

// Move the stepper motor for a specific part
void moveStepper(int stepPin, int dirPin, String part) {
  int stepsToMove = calculateSteps(totalSelected / 2); // Calculate steps (half of TOTAL)
  long initialWeight = 0;

  // Read initial weight from the corresponding load cell
  if (part == "Part A" && scale1.is_ready()) {
    initialWeight = scale1.get_units();
  } else if (part == "Part B" && scale2.is_ready()) {
    initialWeight = scale2.get_units();
  }

  // Set direction (change HIGH/LOW for direction as needed)
  digitalWrite(dirPin, HIGH); 

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print(part + " Dispensing");

  // Move the motor and update the LCD with dispensed volume in ml
  for (int i = 0; i < stepsToMove; i++) {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(800); // Adjust speed (lower value = faster)
    digitalWrite(stepPin, LOW);
    delayMicroseconds(800); // Adjust speed (lower value = faster)

    // Update dispensed volume on the LCD
    if (i % 10 == 0) { // Update LCD every 10 steps for efficiency
      long currentWeight = 0;
      if (part == "Part A" && scale1.is_ready()) {
        currentWeight = scale1.get_units();
      } else if (part == "Part B" && scale2.is_ready()) {
        currentWeight = scale2.get_units();
      }

      long dispensedWeight = currentWeight - initialWeight;
      float dispensedVolume = dispensedWeight / density; // Convert g to ml
      lcd.setCursor(0, 1);
      lcd.print("Dispensing:");
      lcd.print(dispensedVolume, 1); // Show 1 decimal place
      lcd.print("ml ");
    }
  }

  delay(1000); // Pause after dispensing
}

// Calculate steps from ml (placeholder for your equation)
int calculateSteps(int ml) {
  return ml * 10; // Example conversion (adjust as per your system)
}

// Display finished message
void displayFinished() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Dispensing Done!");
  lcd.setCursor(0, 1);
  lcd.print("Press to Restart");
}

// Reset the selection process
void resetSelection() {
  isSelected = false;
  partASelected = false;
  partBSelected = false;
  currentOption = minOption;
  updateLCD();
}