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

int DT = 2;   // GPIO #4-DT on encoder (Output B)
int CLK = 3;  // GPIO #5-CLK on encoder (Output A)

float distanceTraveled = 0;
float deltaFlow = 0;
float bentFlow = 0;
float D_machine = 4.041;
float A_machine = PI * D_machine * D_machine / 4.0;
float D_pipe = 3.996;
float AOC = PI * (D_machine * D_machine - D_pipe * D_pipe) / 4.0;
int aState;
int aLastState;

unsigned long lastDebounceTime = 0;
unsigned long debounceDelay = 75;
unsigned long previousMillis = 0;

// Define LCD dimensions and address
LiquidCrystal_I2C lcd(0x27, 20, 4);  // Set the LCD I2C address and the LCD dimensions (20x4)

void setup() {
  Serial.begin(9600);
  pinMode(CLK, INPUT_PULLUP);
  pinMode(DT, INPUT_PULLUP);
  aLastState = digitalRead(CLK);
  
  // Initialize LCD
  lcd.init();
  lcd.backlight();

  // Display static text on LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("mm/min:");

  lcd.setCursor(0, 1);
  lcd.print("m:");

  lcd.setCursor(0, 2);
  lcd.print("m^3/hr:");

  lcd.setCursor(0, 3);
  lcd.print("L/min:");
}

void loop() {
  aState = digitalRead(CLK);

  if (aState != aLastState) {
    if (millis() - lastDebounceTime > debounceDelay) {
      if (digitalRead(DT) != aState) {
        distanceTraveled += 00.5236;
      } else {
        distanceTraveled -= 0.5236;
      }

      unsigned long currentMillis = millis();
      unsigned long timeDiff = currentMillis - previousMillis;

      float distancePerPulse = 0.5;
      float speed_mm_min = (distancePerPulse / timeDiff) * 60000;
      float speed_m_hr = speed_mm_min * 60 / 1000.0;

      deltaFlow = speed_m_hr * A_machine;
      bentFlow = speed_m_hr * AOC;
      float bentFlow_L_min = bentFlow * 1000 / 60;
      
      lastDebounceTime = millis();
      previousMillis = currentMillis;
      
      // Print to serial
      Serial.print("Speed (mm/min): ");
      Serial.println(speed_mm_min);
      Serial.print("Dist (m): ");
      Serial.println(distanceTraveled / 1000);
      Serial.print("DeltaF (m³/hr): ");
      Serial.println(deltaFlow);
      Serial.print("BentF (L/min): ");
      Serial.println(bentFlow_L_min);

      // Update LCD with new values
      lcd.setCursor(7, 0);  // Adjust the position based on your preference
      lcd.print("   "); // Round to nearest integer for better fit
      lcd.setCursor(7, 0);  // Adjust the position based on your preference
      lcd.print(round(speed_mm_min)); // Round to nearest integer for better fit

      lcd.setCursor(2, 1);  // Adjust the position based on your preference
      lcd.print("   "); // Round to nearest integer for better fit
      lcd.setCursor(2, 1);  // Adjust the position based on your preference
      lcd.print(distanceTraveled / 1000); // Round to nearest integer for better fit

      lcd.setCursor(7, 2);  // Adjust the position based on your preference
      lcd.print("   "); // Round to nearest integer for better fit
      lcd.setCursor(7, 2);  // Adjust the position based on your preference
      lcd.print(round(deltaFlow)); // Round to nearest integer for better fit

      lcd.setCursor(6, 3);  // Adjust the position based on your preference
      lcd.print("   "); // Round to nearest integer for better fit
      lcd.setCursor(6, 3);  // Adjust the position based on your preference
      lcd.print(round(bentFlow_L_min)); // Round to nearest integer for better fit
    }
  }

  aLastState = aState;
}