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

// Define the number of rows and columns for the keypad
const byte ROWS = 4;
const byte COLS = 4;

// Define the symbols on the buttons of the keypad
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};

// Connect keypad ROW0, ROW1, ROW2, ROW3 to these Arduino pins
byte rowPins[ROWS] = {9, 8, 7, 6}; 
// Connect keypad COL0, COL1, COL2, COL3 to these Arduino pins
byte colPins[COLS] = {5, 4, 3, 2}; 

// Create the Keypad object
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// Create the LCD object (using I2C address 0x27)
LiquidCrystal_I2C lcd(0x27, 16, 4);

// LED pins
const int ledPins[8] = {10, 11, 12, 13, 14, 15, 16, 17};

// Command and state variables
String command = "";
String currentA = "";
String currentB = "";
String currentC = "";
bool ledState[8] = {false, false, false, false, false, false, false, false};
bool inCMode = false;

void setup() {
  // Initialize the LCD
  lcd.init();
  lcd.backlight();
  
  // Initialize the LED pins as outputs
  for (int i = 0; i < 8; i++) {
    pinMode(ledPins[i], OUTPUT);
    digitalWrite(ledPins[i], LOW);
  }
  
  // Display initial prompt on the LCD
  lcd.setCursor(0, 0);
  lcd.print("A:    B:    ");
  lcd.setCursor(0, 1);
  lcd.print(">");
}

void loop() {
  char key = keypad.getKey();
  
  if (key) {
    if (key == '*') {
      // Clear input, retain last A, B, and C values
      command = "";
      lcd.setCursor(1, 1);
      lcd.print("                "); // Clear the command area
      lcd.setCursor(1, 1);
    } else if (key == '#') {
      // Refresh LCD
      refreshLCD();
    } else if (key == 'D') {
      // Execute command
      lcd.setCursor(0, 2);
      lcd.print("Executing...");
      executeCommand();
      delay(1000);  // Delay to display "Executing..." message
      lcd.setCursor(0, 2);
      lcd.print("                "); // Clear "Executing..." message
    } else {
      // Append key to the command
      if (command.length() < 8) {
        command += key;
        lcd.setCursor(1, 1);
        lcd.print(command);
        updateLCD();
      }
    }
  }
}

void refreshLCD() {
  lcd.clear();
  if (inCMode) {
    lcd.setCursor(0, 0);
    lcd.print("C:    ");
    lcd.setCursor(2, 0);
    lcd.print(currentC);
  } else {
    lcd.setCursor(0, 0);
    lcd.print("A:    B:    ");
    lcd.setCursor(2, 0);
    lcd.print(currentA);
    lcd.setCursor(8, 0);
    lcd.print(currentB);
  }
  lcd.setCursor(0, 1);
  lcd.print(">");
  lcd.setCursor(1, 1);
  lcd.print(command);
}

void updateLCD() {
  if (command.length() >= 3) {
    lcd.setCursor(2, 0);
    if (command[0] == 'C') {
      lcd.print(command.substring(1, 3));
    } else {
      lcd.print(command.substring(1, 3));
    }
  }
  if (command.length() >= 6 && !inCMode) {
    lcd.setCursor(8, 0);
    lcd.print(command.substring(4, 6));
  }
}

void toggleLED(int index) {
  if (ledState[index]) {
    digitalWrite(ledPins[index], LOW);
    ledState[index] = false;
  } else {
    digitalWrite(ledPins[index], HIGH);
    ledState[index] = true;
  }
}

void executeCommand() {
  String cmd = command;

  if (!inCMode) {
    if (cmd == "A01B01") {
      toggleLED(0);
      currentA = "01";
      currentB = "01";
    } else if (cmd == "A01B02") {
      toggleLED(1);
      currentA = "01";
      currentB = "02";
    } else if (cmd == "A01B03") {
      toggleLED(2);
      currentA = "01";
      currentB = "03";
    } else if (cmd == "A01B04") {
      toggleLED(3);
      currentA = "01";
      currentB = "04";
    } else if (cmd == "A01B05") {
      toggleLED(4);
      currentA = "01";
      currentB = "05";
    } else if (cmd == "A01B06") {
      toggleLED(5);
      currentA = "01";
      currentB = "06";
    } else if (cmd == "A01B07") {
      toggleLED(6);
      currentA = "01";
      currentB = "07";
    } else if (cmd == "A01B08") {
      toggleLED(7);
      currentA = "01";
      currentB = "08";
    } else if (cmd == "A00B99") {
      // Light all LEDs
      for (int i = 0; i < 8; i++) {
        digitalWrite(ledPins[i], HIGH);
        ledState[i] = true;
      }
      currentA = "00";
      currentB = "99";
    } else if (cmd == "A00B00") {
      // Turn off all LEDs
      for (int i = 0; i < 8; i++) {
        digitalWrite(ledPins[i], LOW);
        ledState[i] = false;
      }
      currentA = "00";
      currentB = "00";
    } else if (cmd == "C") {
      inCMode = true;
      currentC = "";
      command = "";
      refreshLCD();
      return;
    } else {
      lcd.setCursor(0, 2);
      lcd.print("Invalid Command");
    }

    lcd.setCursor(2, 0);
    lcd.print(currentA);
    lcd.setCursor(8, 0);
    lcd.print(currentB);
  } else {
    if (cmd == "C00") {
      for (int i = 0; i < 8; i++) {
        digitalWrite(ledPins[i], LOW);
        ledState[i] = false;
      }
      currentC = "00";
    } else if (cmd == "C01") {
      digitalWrite(ledPins[0], HIGH);
      digitalWrite(ledPins[3], HIGH);
      ledState[0] = true;
      ledState[3] = true;
      currentC = "01";
    } else if (cmd == "C02") {
      digitalWrite(ledPins[1], HIGH);
      digitalWrite(ledPins[2], HIGH);
      ledState[1] = true;
      ledState[2] = true;
      currentC = "02";
    } else if (cmd == "C03") {
      digitalWrite(ledPins[0], HIGH);
      digitalWrite(ledPins[1], HIGH);
      ledState[0] = true;
      ledState[1] = true;
      currentC = "03";
    } else if (cmd == "C04") {
      digitalWrite(ledPins[2], HIGH);
      digitalWrite(ledPins[3], HIGH);
      ledState[2] = true;
      ledState[3] = true;
      currentC = "04";
    } else if (cmd == "C05") {
      digitalWrite(ledPins[0], HIGH);
      digitalWrite(ledPins[1], HIGH);
      digitalWrite(ledPins[2], HIGH);
      digitalWrite(ledPins[3], HIGH);
      ledState[0] = true;
      ledState[1] = true;
      ledState[2] = true;
      ledState[3] = true;
      currentC = "05";
    } else if (cmd == "C06") {
      for (int i = 0; i < 6; i++) {
        digitalWrite(ledPins[i], HIGH);
        ledState[i] = true;
      }
      currentC = "06";
    } else if (cmd == "C07") {
      for (int i = 0; i < 7; i++) {
        digitalWrite(ledPins[i], HIGH);
        ledState[i] = true;
      }
      currentC = "07";
    } else if (cmd == "C08") {
      for (int i = 0; i < 8; i++) {
        digitalWrite(ledPins[i], HIGH);
        ledState[i] = true;
      }
      currentC = "08";
    } else if (cmd == "C09") {
      for (int i = 0; i < 8; i++) {
        digitalWrite(ledPins[i], LOW);
        ledState[i] = false;
      }
      currentC = "09";
    } else if (cmd == "C10") {
      for (int i = 0; i < 8; i++) {
        digitalWrite(ledPins[i], HIGH);
        ledState[i] = true;
      }
      currentC = "10";
    } else if (cmd == "C") {
      inCMode = false;
      command = "";
      refreshLCD();
      return;
    } else {
      lcd.setCursor(0, 2);
      lcd.print("Invalid Command");
    }

    lcd.setCursor(2, 0);
    lcd.print(currentC);
  }

  command = "";
  lcd.setCursor(1, 1);
  lcd.print("                "); // Clear the command area
  lcd.setCursor(1, 1);
}