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

// LCD Initialization (20x4, I2C address 0x27)
LiquidCrystal_I2C lcd(0x27, 20, 4);

// Button Pins
#define UP 26
#define DOWN 27
#define LEFT 28
#define RIGHT 29
#define ENTER 30

// Parameters
float voltage = 12.8; // Voltage
int holeInterval = 2; // Hole Interval
int plotDistance = 30; // Plot Distance
int movementSpeed = 50; // Movement Speed
int dispenseSpeed = 50; // Dispense Speed

// Menu Options Array
const char *option[] = {"Config", "AR", "Man"};
const int menuSize = sizeof(option) / sizeof(option[0]); // Calculate menu size
int currentParametersOption = 0; // Selected Option (Configuration, Auto Run, Manual Controller)
bool parametersSelected = false; // Enter Button State

void setup() {
  // Initialize LCD
  lcd.init();
  lcd.backlight();
  
  // Display Startup Screen
  lcd.setCursor(0, 0); lcd.print(" Seed Sowing Robot  ");
  lcd.setCursor(0, 1); lcd.print("     Version 1.0    ");
  lcd.setCursor(0, 2); lcd.print("Southern Luzon State");
  lcd.setCursor(0, 3); lcd.print("     University     ");

  // Keypad Button Setup
  pinMode(UP, INPUT_PULLUP);
  pinMode(DOWN, INPUT_PULLUP);
  pinMode(LEFT, INPUT_PULLUP);
  pinMode(RIGHT, INPUT_PULLUP);
  pinMode(ENTER, INPUT_PULLUP);

  delay(1000);
  parametersMainScreen();
}

void loop() {
  // Move Left
  if (digitalRead(LEFT) == LOW) {
    moveLeft();
    delay(300);
  }

  // Move Right
  if (digitalRead(RIGHT) == LOW) {
    moveRight();
    delay(300);
  }

  // Enter Selection
  if (digitalRead(ENTER) == LOW) {
    selectOption();
    delay(300);
  }
}

// Display Parameters Screen
void parametersMainScreen() {
  lcd.clear();
  lcd.backlight();
  
  // Display Titles
  lcd.setCursor(0, 0); lcd.print("     Parameters     ");
  
  // Display Values
  lcd.setCursor(0, 1); lcd.print("V= "); lcd.print(voltage); lcd.print("V HI= "); lcd.print(holeInterval); lcd.print("ft.");
  lcd.setCursor(0, 2); lcd.print("L= "); lcd.print(plotDistance); lcd.print("ft.  SL= "); lcd.print(movementSpeed); lcd.print("%");

  // Display Menu Options
  lcd.setCursor(0, 3);
  for (int i = 0; i < menuSize; i++) {
    if (i == currentParametersOption) {
      lcd.print(">"); // Highlight current selection
    } else {
      lcd.print(" ");
    }
    lcd.print(option[i]);
    lcd.print("  "); // Space between options
  }
}

// Move Selection Left
void moveLeft() {
  if (currentParametersOption == 0) {
    currentParametersOption = menuSize - 1; // Loop back to last option
  } else {
    currentParametersOption--; // Move left
  }
  parametersMainScreen(); // Refresh LCD
}

// Move Selection Right
void moveRight() {
  if (currentParametersOption == menuSize - 1) {
    currentParametersOption = 0; // Loop back to first option
  } else {
    currentParametersOption++; // Move right
  }
  parametersMainScreen(); // Refresh LCD
}

// Select Current Option
void selectOption() {
  lcd.clear();
  lcd.setCursor(4, 1);
  lcd.print("Selected:");
  lcd.setCursor(8, 2);
  lcd.print(option[currentParametersOption]);

  delay(2000); // Display selection confirmation
  parametersMainScreen(); // Return to menu
}