WS10

.idea/.gitignore

@@ -0,0 +1,10 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Ignored default folder with query files
+/queries/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml
+# Editor-based HTTP Client requests
+/httpRequests/

.idea/compiler.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CompilerConfiguration">
+    <annotationProcessing>
+      <profile name="Maven default annotation processors profile" enabled="true">
+        <sourceOutputDir name="target/generated-sources/annotations" />
+        <sourceTestOutputDir name="target/generated-test-sources/test-annotations" />
+        <outputRelativeToContentRoot value="true" />
+        <module name="WS-10-Database" />
+      </profile>
+    </annotationProcessing>
+  </component>
+</project>

.idea/encodings.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Encoding">
+    <file url="file://$PROJECT_DIR$/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/src/main/resources" charset="UTF-8" />
+  </component>
+</project>

.idea/jarRepositories.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="RemoteRepositoriesConfiguration">
+    <remote-repository>
+      <option name="id" value="central" />
+      <option name="name" value="Maven Central repository" />
+      <option name="url" value="https://repo1.maven.org/maven2" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="jboss.community" />
+      <option name="name" value="JBoss Community repository" />
+      <option name="url" value="https://repository.jboss.org/nexus/content/repositories/public/" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="central" />
+      <option name="name" value="Central Repository" />
+      <option name="url" value="https://mirror-maven.runflare.com/maven2" />
+    </remote-repository>
+  </component>
+</project>

.idea/misc.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ExternalStorageConfigurationManager" enabled="true" />
+  <component name="MavenProjectsManager">
+    <option name="originalFiles">
+      <list>
+        <option value="$PROJECT_DIR$/pom.xml" />
+      </list>
+    </option>
+  </component>
+  <component name="ProjectRootManager" version="2" project-jdk-name="25" project-jdk-type="JavaSDK" />
+</project>

.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>

src/main/java/dev/Main.java

@@ -8,7 +8,5 @@ public class Main {
 
         ConsoleMenu menu = new ConsoleMenu();
         menu.start();
-
     }
-
 }

src/main/java/dev/dao/MenuItemDao.java

@@ -1,7 +1,14 @@
 package dev.dao;
 
+import dev.database.DatabaseConnection;
 import dev.model.MenuItem;
 
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.ArrayList;
 import java.util.List;
 
 public class MenuItemDao {
@@ -11,7 +18,30 @@ public class MenuItemDao {
         // TODO:
         // Retrieve all menu items
 
-        return null;
+        String sql = "SELECT id, name, description, price, category FROM menu_items ORDER BY id";
+
+        List<MenuItem> menuItems = new ArrayList<>();
+
+        try (Connection connection = DatabaseConnection.getConnection();
+             Statement statement = connection.createStatement();
+             ResultSet resultSet = statement.executeQuery(sql)) {
+
+            while (resultSet.next()) {
+                menuItems.add(new MenuItem(
+                        resultSet.getInt("id"),
+                        resultSet.getString("name"),
+                        resultSet.getString("description"),
+                        resultSet.getDouble("price"),
+                        resultSet.getString("category")
+                ));
+            }
+
+            return menuItems;
+
+        } catch (SQLException e) {
+            System.out.println("Error retrieving menu items: " + e.getMessage());
+            return menuItems;
+        }
     }
 
     public MenuItem findById(int id) {
@@ -19,7 +49,32 @@ public class MenuItemDao {
         // TODO:
         // Find menu item by id
 
-        return null;
+        String sql = "SELECT id, name, description, price, category FROM menu_items WHERE id = ?";
+
+        try (Connection connection = DatabaseConnection.getConnection();
+             PreparedStatement statement = connection.prepareStatement(sql)) {
+
+            statement.setInt(1, id);
+
+            try (ResultSet resultSet = statement.executeQuery()) {
+
+                if (resultSet.next()) {
+                    return new MenuItem(
+                            resultSet.getInt("id"),
+                            resultSet.getString("name"),
+                            resultSet.getString("description"),
+                            resultSet.getDouble("price"),
+                            resultSet.getString("category")
+                    );
+                }
+
+                return null;
+            }
+
+        } catch (SQLException e) {
+            System.out.println("Error finding menu item: " + e.getMessage());
+            return null;
+        }
     }
 
 }

src/main/java/dev/dao/OrderDao.java

@@ -1,7 +1,15 @@
 package dev.dao;
 
+import dev.database.DatabaseConnection;
 import dev.model.Order;
 
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.sql.Timestamp;
+import java.util.ArrayList;
 import java.util.List;
 
 public class OrderDao {
@@ -11,7 +19,30 @@ public class OrderDao {
         // TODO:
         // Insert order and return generated id
 
-        return -1;
+        String sql = "INSERT INTO orders (user_id, created_at, total_price) VALUES (?, ?, ?)";
+
+        try (Connection connection = DatabaseConnection.getConnection();
+             PreparedStatement statement = connection.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS)) {
+
+            statement.setInt(1, order.getUserId());
+            statement.setTimestamp(2, Timestamp.valueOf(order.getCreatedAt()));
+            statement.setDouble(3, order.getTotalPrice());
+
+            statement.executeUpdate();
+
+            try (ResultSet generatedKeys = statement.getGeneratedKeys()) {
+
+                if (generatedKeys.next()) {
+                    return generatedKeys.getInt(1);
+                }
+
+                return -1;
+            }
+
+        } catch (SQLException e) {
+            System.out.println("Error saving order: " + e.getMessage());
+            return -1;
+        }
     }
 
     public List<Order> findByUserId(int userId) {
@@ -19,7 +50,33 @@ public class OrderDao {
         // TODO:
         // Retrieve all orders of a user
 
-        return null;
+        String sql = "SELECT id, user_id, created_at, total_price FROM orders WHERE user_id = ? ORDER BY created_at";
+
+        List<Order> orders = new ArrayList<>();
+
+        try (Connection connection = DatabaseConnection.getConnection();
+             PreparedStatement statement = connection.prepareStatement(sql)) {
+
+            statement.setInt(1, userId);
+
+            try (ResultSet resultSet = statement.executeQuery()) {
+
+                while (resultSet.next()) {
+                    orders.add(new Order(
+                            resultSet.getInt("id"),
+                            resultSet.getInt("user_id"),
+                            resultSet.getTimestamp("created_at").toLocalDateTime(),
+                            resultSet.getDouble("total_price")
+                    ));
+                }
+
+                return orders;
+            }
+
+        } catch (SQLException e) {
+            System.out.println("Error retrieving orders: " + e.getMessage());
+            return orders;
+        }
     }
 
 }

src/main/java/dev/dao/OrderDetailDao.java

@@ -1,7 +1,13 @@
 package dev.dao;
 
+import dev.database.DatabaseConnection;
 import dev.model.OrderDetail;
 
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.ArrayList;
 import java.util.List;
 
 public class OrderDetailDao {
@@ -11,6 +17,21 @@ public class OrderDetailDao {
         // TODO:
         // Insert order detail
 
+        String sql = "INSERT INTO order_details (order_id, menu_item_id, quantity, price) VALUES (?, ?, ?, ?)";
+
+        try (Connection connection = DatabaseConnection.getConnection();
+             PreparedStatement statement = connection.prepareStatement(sql)) {
+
+            statement.setInt(1, detail.getOrderId());
+            statement.setInt(2, detail.getMenuItemId());
+            statement.setInt(3, detail.getQuantity());
+            statement.setDouble(4, detail.getPrice());
+
+            statement.executeUpdate();
+
+        } catch (SQLException e) {
+            System.out.println("Error saving order detail: " + e.getMessage());
+        }
     }
 
     public List<OrderDetail> findByOrderId(int orderId) {
@@ -18,7 +39,34 @@ public class OrderDetailDao {
         // TODO:
         // Retrieve order details
 
-        return null;
+        String sql = "SELECT id, order_id, menu_item_id, quantity, price FROM order_details WHERE order_id = ?";
+
+        List<OrderDetail> details = new ArrayList<>();
+
+        try (Connection connection = DatabaseConnection.getConnection();
+             PreparedStatement statement = connection.prepareStatement(sql)) {
+
+            statement.setInt(1, orderId);
+
+            try (ResultSet resultSet = statement.executeQuery()) {
+
+                while (resultSet.next()) {
+                    details.add(new OrderDetail(
+                            resultSet.getInt("id"),
+                            resultSet.getInt("order_id"),
+                            resultSet.getInt("menu_item_id"),
+                            resultSet.getInt("quantity"),
+                            resultSet.getDouble("price")
+                    ));
+                }
+
+                return details;
+            }
+
+        } catch (SQLException e) {
+            System.out.println("Error retrieving order details: " + e.getMessage());
+            return details;
+        }
     }
 
 }

src/main/java/dev/dao/UserDao.java

@@ -1,7 +1,13 @@
 package dev.dao;
 
+import dev.database.DatabaseConnection;
 import dev.model.User;
 
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
 public class UserDao {
 
     public boolean save(User user) {
@@ -9,7 +15,17 @@ public class UserDao {
         // TODO:
         // Insert user into database
 
-        return false;
+        String sql = "INSERT INTO users (username, password, email) VALUES (?, ?, ?)";
+        try (Connection connection = DatabaseConnection.getConnection();
+             PreparedStatement statement = connection.prepareStatement(sql)) {
+            statement.setString(1, user.getUsername());
+            statement.setString(2, user.getPassword());
+            statement.setString(3, user.getEmail());
+            return statement.executeUpdate() > 0;
+        } catch (SQLException e) {
+            System.out.println("Error saving user: " + e.getMessage());
+            return false;
+        }
     }
 
     public User findByUsername(String username) {
@@ -17,7 +33,27 @@ public class UserDao {
         // TODO:
         // Find a user by username
 
-        return null;
+        String sql = "SELECT id, username, password, email FROM users WHERE username = ?";
+
+        try (Connection connection = DatabaseConnection.getConnection();
+             PreparedStatement statement = connection.prepareStatement(sql)) {
+            statement.setString(1, username);
+            try (ResultSet resultSet = statement.executeQuery()) {
+                if (resultSet.next()) {
+                    return new User(
+                            resultSet.getInt("id"),
+                            resultSet.getString("username"),
+                            resultSet.getString("password"),
+                            resultSet.getString("email")
+                    );
+                }
+                return null;
+            }
+
+        } catch (SQLException e) {
+            System.out.println("Error finding user: " + e.getMessage());
+            return null;
+        }
     }
 
 }

src/main/java/dev/database/DatabaseConnection.java

@@ -19,9 +19,6 @@ public class DatabaseConnection {
             throws SQLException {
 
         // TODO:
-        // Return a valid PostgreSQL connection
+        return java.sql.DriverManager.getConnection(URL, USER, PASSWORD);
-
-        return null;
     }
-
 }

src/main/java/dev/model/MenuItem.java

@@ -12,4 +12,56 @@ public class MenuItem {
 
     private String category;
 
+    public MenuItem() {
+
+    }
+
+    public MenuItem(int id, String name, String description, double price, String category) {
+        this.id = id;
+        this.name = name;
+        this.description = description;
+        this.price = price;
+        this.category = category;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    public double getPrice() {
+        return price;
+    }
+
+    public void setPrice(double price) {
+        this.price = price;
+    }
+
+    public String getCategory() {
+        return category;
+    }
+
+    public void setCategory(String category) {
+        this.category = category;
+    }
+
 }

src/main/java/dev/model/Order.java

@@ -12,4 +12,47 @@ public class Order {
 
     private double totalPrice;
 
+    public Order() {
+
+    }
+
+    public Order(int id, int userId, LocalDateTime createdAt, double totalPrice) {
+        this.id = id;
+        this.userId = userId;
+        this.createdAt = createdAt;
+        this.totalPrice = totalPrice;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public int getUserId() {
+        return userId;
+    }
+
+    public void setUserId(int userId) {
+        this.userId = userId;
+    }
+
+    public LocalDateTime getCreatedAt() {
+        return createdAt;
+    }
+
+    public void setCreatedAt(LocalDateTime createdAt) {
+        this.createdAt = createdAt;
+    }
+
+    public double getTotalPrice() {
+        return totalPrice;
+    }
+
+    public void setTotalPrice(double totalPrice) {
+        this.totalPrice = totalPrice;
+    }
+
 }

src/main/java/dev/model/OrderDetail.java

@@ -12,4 +12,55 @@ public class OrderDetail {
 
     private double price;
 
+    public OrderDetail() {
+    }
+
+    public OrderDetail(int id, int orderId, int menuItemId, int quantity, double price) {
+        this.id = id;
+        this.orderId = orderId;
+        this.menuItemId = menuItemId;
+        this.quantity = quantity;
+        this.price = price;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public int getOrderId() {
+        return orderId;
+    }
+
+    public void setOrderId(int orderId) {
+        this.orderId = orderId;
+    }
+
+    public int getMenuItemId() {
+        return menuItemId;
+    }
+
+    public void setMenuItemId(int menuItemId) {
+        this.menuItemId = menuItemId;
+    }
+
+    public int getQuantity() {
+        return quantity;
+    }
+
+    public void setQuantity(int quantity) {
+        this.quantity = quantity;
+    }
+
+    public double getPrice() {
+        return price;
+    }
+
+    public void setPrice(double price) {
+        this.price = price;
+    }
+
 }

src/main/java/dev/model/User.java

@@ -10,4 +10,47 @@ public class User {
 
     private String email;
 
+    public User() {
+
+    }
+
+    public User(int id, String username, String password, String email) {
+        this.id = id;
+        this.username = username;
+        this.password = password;
+        this.email = email;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    public void setPassword(String password) {
+        this.password = password;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
 }

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

@@ -1,15 +1,33 @@
 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();
+
     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 exists.");
+            return false;
+        }
+
+        User user = new User(0, username, hashPassword(password), email);
+
+        return userDao.save(user);
     }
 
     public User login(String username, String password) {
@@ -17,7 +35,44 @@ public class AuthService {
         // TODO:
         // Authenticate user
 
-        return null;
+        User user = userDao.findByUsername(username);
+
+        if (user == null) {
+            System.out.println("Invalid username or password.");
+            return null;
+        }
+
+        if (!user.getPassword().equals(hashPassword(password))) {
+            System.out.println("Invalid username or password.");
+            return null;
+        }
+
+        return user;
+    }
+
+    private String hashPassword(String password) {
+
+        try {
+            MessageDigest digest = MessageDigest.getInstance("SHA-256");
+            byte[] hashedBytes = digest.digest(password.getBytes());
+
+            StringBuilder hexString = new StringBuilder();
+
+            for (byte b : hashedBytes) {
+                String hex = Integer.toHexString(0xff & b);
+
+                if (hex.length() == 1) {
+                    hexString.append('0');
+                }
+
+                hexString.append(hex);
+            }
+
+            return hexString.toString();
+
+        } catch (NoSuchAlgorithmException e) {
+            throw new RuntimeException(e);
+        }
     }
 
 }

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

@@ -1,12 +1,31 @@
 package dev.service;
 
+import dev.dao.MenuItemDao;
+import dev.model.MenuItem;
+
+import java.util.List;
+
 public class MenuService {
 
+    private final MenuItemDao menuItemDao = new MenuItemDao();
+
     public void showMenu() {
 
         // TODO:
         // Display menu items
 
+        List<MenuItem> menuItems = menuItemDao.findAll();
+
+        System.out.println("Available Items:");
+
+        for (MenuItem item : menuItems) {
+            System.out.printf("%d. %s - $%.2f%n", item.getId(), item.getName(), item.getPrice());
+        }
+    }
+
+    public List<MenuItem> getMenu() {
+
+        return menuItemDao.findAll();
     }
 
 }

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

@@ -1,12 +1,97 @@
 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.time.LocalDateTime;
+import java.util.List;
+import java.util.Scanner;
+
 public class OrderService {
 
+    private final MenuItemDao menuItemDao = new MenuItemDao();
+
+    private final OrderDao orderDao = new OrderDao();
+
+    private final OrderDetailDao orderDetailDao = new OrderDetailDao();
+
+    private final Scanner scanner = new Scanner(System.in);
+
     public void placeOrder(int userId) {
 
         // TODO:
         // Create order
 
+        List<MenuItem> menuItems = menuItemDao.findAll();
+
+        System.out.println("Available Items:");
+
+        for (MenuItem item : menuItems) {
+            System.out.printf("%d. %s - $%.2f%n", item.getId(), item.getName(), item.getPrice());
+        }
+
+        List<OrderDetail> cart = new java.util.ArrayList<>();
+
+        double total = 0;
+
+        while (true) {
+
+            System.out.print("Enter the ID of the item to add (or 0 to finish): ");
+            int itemId = scanner.nextInt();
+
+            if (itemId == 0) {
+                break;
+            }
+
+            MenuItem selected = menuItemDao.findById(itemId);
+
+            if (selected == null) {
+                System.out.println("Invalid item ID.");
+                continue;
+            }
+
+            System.out.print("Enter quantity: ");
+            int quantity = scanner.nextInt();
+
+            if (quantity <= 0) {
+                System.out.println("Quantity must be greater than zero.");
+                continue;
+            }
+
+            OrderDetail detail = new OrderDetail(0, 0, selected.getId(), quantity, selected.getPrice());
+            cart.add(detail);
+
+            total += selected.getPrice() * quantity;
+
+            System.out.printf("Added %dx %s to your cart.%n", quantity, selected.getName());
+        }
+
+        if (cart.isEmpty()) {
+            System.out.println("No items were added to the order.");
+            return;
+        }
+
+        Order order = new Order(0, userId, LocalDateTime.now(), total);
+
+        int orderId = orderDao.save(order);
+
+        if (orderId == -1) {
+            System.out.println("Failed to save order.");
+            return;
+        }
+
+        for (OrderDetail detail : cart) {
+            detail.setOrderId(orderId);
+            orderDetailDao.save(detail);
+        }
+
+        System.out.println("Order saved successfully!");
+
+        printReceipt(orderId);
     }
 
     public void printReceipt(int orderId) {
@@ -14,6 +99,26 @@ public class OrderService {
         // TODO:
         // Print order receipt
 
+        List<OrderDetail> details = orderDetailDao.findByOrderId(orderId);
+
+        System.out.println("---------------------------------------");
+        System.out.printf("%-12s %-7s %-9s %-9s%n", "Item", "Qty", "Unit", "Total");
+        System.out.println("---------------------------------------");
+
+        double grandTotal = 0;
+
+        for (OrderDetail detail : details) {
+
+            MenuItem item = menuItemDao.findById(detail.getMenuItemId());
+            double subtotal = detail.getPrice() * detail.getQuantity();
+            grandTotal += subtotal;
+
+            System.out.printf("%-12s %-7d $%-8.2f $%-8.2f%n",
+                    item.getName(), detail.getQuantity(), detail.getPrice(), subtotal);
+        }
+
+        System.out.println("---------------------------------------");
+        System.out.printf("Final Total: $%.2f%n", grandTotal);
     }
 
     public void showOrderHistory(int userId) {
@@ -21,6 +126,19 @@ public class OrderService {
         // TODO:
         // Display user's order history
 
+        List<Order> orders = orderDao.findByUserId(userId);
+
+        if (orders.isEmpty()) {
+            System.out.println("No orders found.");
+            return;
+        }
+
+        System.out.println("Order History:");
+
+        for (Order order : orders) {
+            System.out.printf("Order #%d - %s - Total: $%.2f%n",
+                    order.getId(), order.getCreatedAt(), order.getTotalPrice());
+        }
     }
 
 }

src/main/java/dev/ui/ConsoleMenu.java

@@ -1,5 +1,10 @@
 package dev.ui;
 
+import dev.model.User;
+import dev.service.AuthService;
+import dev.service.MenuService;
+import dev.service.OrderService;
+
 import java.util.Scanner;
 
 public class ConsoleMenu {
@@ -7,6 +12,12 @@ public class ConsoleMenu {
     private final Scanner scanner =
             new Scanner(System.in);
 
+    private final AuthService authService = new AuthService();
+
+    private final MenuService menuService = new MenuService();
+
+    private final OrderService orderService = new OrderService();
+
     public void start() {
 
         while (true) {
@@ -23,10 +34,12 @@ public class ConsoleMenu {
 
                 case 1:
                     // TODO
+                    login();
                     break;
 
                 case 2:
                     // TODO
+                    register();
                     break;
 
                 case 3:
@@ -41,4 +54,88 @@ public class ConsoleMenu {
 
     }
 
+    private void register() {
+
+        System.out.println();
+        System.out.println("[Register]");
+
+        System.out.print("Enter username: ");
+        String username = scanner.next();
+
+        System.out.print("Enter password: ");
+        String password = scanner.next();
+
+        System.out.print("Enter email (optional, press enter to skip): ");
+        scanner.nextLine();
+        String email = scanner.nextLine();
+
+        if (email.isBlank()) {
+            email = null;
+        }
+
+        if (authService.register(username, password, email)) {
+            System.out.println("Registration successful! You can now login.");
+        }
+
+    }
+
+    private void login() {
+
+        System.out.println();
+        System.out.println("[Login]");
+
+        System.out.print("Enter username: ");
+        String username = scanner.next();
+
+        System.out.print("Enter password: ");
+        String password = scanner.next();
+
+        User user = authService.login(username, password);
+
+        if (user != null) {
+            System.out.println("Login successful! Welcome, " + user.getUsername() + "!");
+            showMainMenu(user);
+        }
+
+    }
+
+    private void showMainMenu(User user) {
+
+        while (true) {
+
+            System.out.println();
+            System.out.println("===== MAIN MENU =====");
+            System.out.println("1. View Menu");
+            System.out.println("2. Place a New Order");
+            System.out.println("3. View Order History");
+            System.out.println("4. Logout");
+
+            int choice = scanner.nextInt();
+
+            switch (choice) {
+
+                case 1:
+                    menuService.showMenu();
+                    break;
+
+                case 2:
+                    orderService.placeOrder(user.getId());
+                    break;
+
+                case 3:
+                    orderService.showOrderHistory(user.getId());
+                    break;
+
+                case 4:
+                    return;
+
+                default:
+                    System.out.println("Invalid choice");
+
+            }
+
+        }
+
+    }
+
 }