src/main/java/dev/service/AuthService.java

@@ -1,23 +1,51 @@
 package dev.service;
 
+import dev.dao.UserDao;
 import dev.model.User;
 
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
 public class AuthService {
 
+    private final UserDao userDao = new UserDao();
+
+
+    private String hashPassword(String password) {
+        try {
+            MessageDigest md = MessageDigest.getInstance("SHA-256");
+            byte[] hash = md.digest(password.getBytes());
+            StringBuilder sb = new StringBuilder();
+            for (byte b : hash) sb.append(String.format("%02x", b));
+            return sb.toString();
+        } catch (NoSuchAlgorithmException e) {
+            throw new RuntimeException("Hashing error", e);
+        }
+    }
+
     public boolean register(String username, String password, String email) {
-
-        // TODO:
-        // Validate and register user
-
-        return false;
+        if (username == null || username.isBlank() || password == null || password.isBlank()) {
+            System.out.println("Username and password are required.");
+            return false;
+        }
+        if (userDao.findByUsername(username) != null) {
+            System.out.println("Username already taken.");
+            return false;
+        }
+        User user = new User(username, hashPassword(password), email.isBlank() ? null : email);
+        return userDao.save(user);
     }
 
     public User login(String username, String password) {
-
-        // TODO:
-        // Authenticate user
-
-        return null;
+        User user = userDao.findByUsername(username);
+        if (user == null) {
+            System.out.println("User not found.");
+            return null;
+        }
+        if (!user.getPassword().equals(hashPassword(password))) {
+            System.out.println("Incorrect password.");
+            return null;
+        }
+        return user;
     }
-
 }

src/main/java/dev/service/MenuService.java

@@ -1,12 +1,27 @@
 package dev.service;
 
+import dev.dao.MenuItemDao;
+import dev.model.MenuItem;
+
+import java.util.List;
+
 public class MenuService {
 
-    public void showMenu() {
-
-        // TODO:
-        // Display menu items
+    private final MenuItemDao menuItemDao = new MenuItemDao();
 
+    public List<MenuItem> getMenuItems() {
+        return menuItemDao.findAll();
     }
 
+    public void showMenu() {
+        List<MenuItem> items = getMenuItems();
+        System.out.println("\n--- MENU ---");
+        System.out.printf("%-5s %-25s %-12s %s%n", "ID", "Name", "Price", "Category");
+        System.out.println("-".repeat(55));
+        for (MenuItem item : items) {
+            System.out.printf("%-5d %-25s $%-11.2f %s%n",
+                    item.getId(), item.getName(), item.getPrice(), item.getCategory());
+        }
+        System.out.println("-".repeat(55));
+    }
 }

src/main/java/dev/service/OrderService.java

@@ -1,26 +1,101 @@
 package dev.service;
 
+import dev.dao.MenuItemDao;
+import dev.dao.OrderDao;
+import dev.dao.OrderDetailDao;
+import dev.model.MenuItem;
+import dev.model.Order;
+import dev.model.OrderDetail;
+
+import java.util.*;
+
 public class OrderService {
 
+    private final MenuItemDao    menuItemDao    = new MenuItemDao();
+    private final OrderDao       orderDao       = new OrderDao();
+    private final OrderDetailDao orderDetailDao = new OrderDetailDao();
+    private final MenuService    menuService    = new MenuService();
+    private final Scanner        scanner        = new Scanner(System.in);
+
     public void placeOrder(int userId) {
+        menuService.showMenu();
+        
+        Map<Integer, int[]> cart = new LinkedHashMap<>();  // int[] = {quantity}
+        Map<Integer, MenuItem> itemMap = new HashMap<>();
 
-        // TODO:
-        // Create order
+        while (true) {
+            System.out.print("\nEnter item ID to add (0 to finish): ");
+            int id = scanner.nextInt();
+            if (id == 0) break;
 
+            MenuItem item = menuItemDao.findById(id);
+            if (item == null) {
+                System.out.println("Item not found, try again.");
+                continue;
+            }
+            System.out.print("Enter quantity: ");
+            int qty = scanner.nextInt();
+            if (qty <= 0) { System.out.println("Quantity must be > 0."); continue; }
+
+            cart.merge(id, new int[]{qty}, (a, b) -> new int[]{a[0] + b[0]});
+            itemMap.put(id, item);
+            System.out.printf("Added %dx %s%n", qty, item.getName());
+        }
+
+        if (cart.isEmpty()) { System.out.println("No items selected."); return; }
+
+        // Calculate total
+        double total = cart.entrySet().stream()
+                .mapToDouble(e -> itemMap.get(e.getKey()).getPrice() * e.getValue()[0])
+                .sum();
+
+        // Save order
+        Order order = new Order(userId, total);
+        int orderId = orderDao.save(order);
+        if (orderId == -1) { System.out.println("Failed to save order."); return; }
+
+        // Save order details
+        for (Map.Entry<Integer, int[]> entry : cart.entrySet()) {
+            MenuItem item = itemMap.get(entry.getKey());
+            OrderDetail detail = new OrderDetail(orderId, item.getId(), entry.getValue()[0], item.getPrice());
+            orderDetailDao.save(detail);
+        }
+
+        printReceipt(orderId);
     }
 
     public void printReceipt(int orderId) {
+        List<OrderDetail> details = orderDetailDao.findByOrderId(orderId);
+        System.out.println("\n--- RECEIPT ---");
+        System.out.printf("%-20s %5s  %8s  %8s%n", "Item", "Qty", "Unit", "Total");
+        System.out.println("-".repeat(47));
 
-        // TODO:
-        // Print order receipt
+        double grandTotal = 0;
+        for (OrderDetail d : details) {
+            MenuItem item = menuItemDao.findById(d.getMenuItemId());
+            String name = (item != null) ? item.getName() : "Unknown";
+            double subtotal = d.getPrice() * d.getQuantity();
+            grandTotal += subtotal;
+            System.out.printf("%-20s %5d  $%7.2f  $%7.2f%n",
+                    name, d.getQuantity(), d.getPrice(), subtotal);
+        }
 
+        System.out.println("-".repeat(47));
+        System.out.printf("%-20s %18s $%7.2f%n", "TOTAL", "", grandTotal);
+        System.out.println("Order saved successfully!");
     }
 
     public void showOrderHistory(int userId) {
+        List<Order> orders = orderDao.findByUserId(userId);
+        if (orders.isEmpty()) { System.out.println("No past orders."); return; }
 
-        // TODO:
-        // Display user's order history
-
+        System.out.println("\n--- ORDER HISTORY ---");
+        System.out.printf("%-8s %-25s %s%n", "Order#", "Date", "Total");
+        System.out.println("-".repeat(45));
+        for (Order o : orders) {
+            System.out.printf("%-8d %-25s $%.2f%n",
+                    o.getId(), o.getCreatedAt().toString().replace("T", " "), o.getTotalPrice());
+        }
+        System.out.println("-".repeat(45));
     }
-
 }