#include <LiquidCrystal.h>
#include <Keypad.h>
#include <RotaryEncoder.h>

// Initialize the LCD with the specified pins
LiquidCrystal lcd(7, 8, 9, 10, 11, 12);

// Keypad configuration
const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
    {'1', '2', '3', 'A'},
    {'4', '5', '6', 'B'},
    {'7', '8', '9', 'C'},
    {'*', '0', '#', 'D'}
};
byte rowPins[ROWS] = {2, 3, 4, 5};
byte colPins[COLS] = {6, A0, A1, A2};
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// Rotary encoder configuration
#define ENCODER_CLK A3
#define ENCODER_DT A4
#define ENCODER_SW A5
RotaryEncoder encoder(ENCODER_CLK, ENCODER_DT);

// Variables for dispensing
int mlToDispense = 0;
bool dispensing = false;
unsigned long dispensingStartTime = 0;

void setup() {
    Serial.begin(9600); // Initialize serial communication for debugging
    lcd.begin(16, 2);
    displayWelcomeMessage();
    displayEnterQuantity();
}

void loop() {
    char key = keypad.getKey();
    if (!dispensing && key) {
        if (key >= '0' && key <= '9') {
            mlToDispense = mlToDispense * 10 + (key - '0');
            lcd.print(key);
        } else if (key == '#') {
            startDispensing();
        } else if (key == '*') {
            mlToDispense = 0;
            displayEnterQuantity();
        }
    }

    if (dispensing) {
        if (millis() - dispensingStartTime >= 4000) { // Dispense for 4 seconds
            stopDispensing();
        }
    }
}

void displayWelcomeMessage() {
    lcd.clear();
    lcd.print("Welcome to");
    lcd.setCursor(0, 1);
    lcd.print("Milk Dispenser!");
    delay(2000); // Display message for 2 seconds
}

void displayEnterQuantity() {
    lcd.clear();
    lcd.print("Enter quantity");
    lcd.setCursor(0, 1);
    lcd.print("of milk: ");
}

void startDispensing() {
    Serial.println("Dispensing started"); // Debug statement
    lcd.clear();
    lcd.print("Dispensing ");
    lcd.print(mlToDispense);
    lcd.print(" ml");
    dispensingStartTime = millis();
    dispensing = true;
    // Here you would turn on the pump or valve
    attachInterrupt(digitalPinToInterrupt(ENCODER_CLK), readEncoder, CHANGE);
    attachInterrupt(digitalPinToInterrupt(ENCODER_DT), readEncoder, CHANGE);
    Serial.println("Interrupts attached"); // Debug statement
}

void stopDispensing() {
    // Here you would turn off the pump or valve
    lcd.clear();
    lcd.print(mlToDispense);
    lcd.print(" ml dispensed");
    lcd.setCursor(0, 1);
    lcd.print("Thank you!");
    Serial.println("Dispensing stopped"); // Debug statement
    dispensing = false;
    mlToDispense = 0;
    delay(10000); // Display message for 10 seconds
    detachInterrupt(digitalPinToInterrupt(ENCODER_CLK));
    detachInterrupt(digitalPinToInterrupt(ENCODER_DT));
    Serial.println("Interrupts detached"); // Debug statement
    displayEnterQuantity();
}

void readEncoder() {
    encoder.tick();
}