adding codes

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

@@ -1,7 +1,14 @@
 package dev.dao;
 
 import dev.model.MenuItem;
+import dev.database.DatabaseConnection;
 
+import java.math.BigDecimal;
+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 MenuItemDao {
@@ -11,7 +18,23 @@ public class MenuItemDao {
         // TODO:
         // Retrieve all menu items
 
-        return null;
+       // return null;
+        List<MenuItem> menuItems = new ArrayList<>();
+        String sql = "SELECT id, name, description, price, category FROM menu_items";
+
+        try (Connection conn = DatabaseConnection.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql);
+             ResultSet rs = stmt.executeQuery()) {
+
+            while (rs.next()) {
+                menuItems.add(mapRowToMenuItem(rs));
+            }
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+
+        return menuItems;
     }
 
     public MenuItem findById(int id) {
@@ -19,7 +42,32 @@ public class MenuItemDao {
         // TODO:
         // Find menu item by id
 
+        String sql = "SELECT id, name, description, price, category FROM menu_items WHERE id = ?";
+
+        try (Connection conn = DatabaseConnection.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql)) {
+
+            stmt.setInt(1, id);
+
+            try (ResultSet rs = stmt.executeQuery()) {
+                if (rs.next()) {
+                    return mapRowToMenuItem(rs);
+                }
+            }
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+
         return null;
     }
+    private MenuItem mapRowToMenuItem(ResultSet rs) throws SQLException {
+        int id = rs.getInt("id");
+        String name = rs.getString("name");
+        String description = rs.getString("description");
+        BigDecimal price = rs.getBigDecimal("price");
+        String category = rs.getString("category");
 
-}
+        return new MenuItem(id, name, description, price, category);
+    }
+}

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

@@ -1,7 +1,16 @@
 package dev.dao;
 
 import dev.model.Order;
+import dev.database.DatabaseConnection;
 
+import java.math.BigDecimal;
+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 {
@@ -10,6 +19,25 @@ public class OrderDao {
 
         // TODO:
         // Insert order and return generated id
+        String sql = "INSERT INTO orders (user_id, total_price) VALUES (?, ?)";
+
+        try (Connection conn = DatabaseConnection.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS)) {
+
+            stmt.setInt(1, order.getUserId());
+            stmt.setBigDecimal(2, order.getTotalPrice());
+
+            stmt.executeUpdate();
+
+            try (ResultSet rs = stmt.getGeneratedKeys()) {
+                if (rs.next()) {
+                    return rs.getInt(1);
+                }
+            }
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
 
         return -1;
     }
@@ -18,8 +46,30 @@ public class OrderDao {
 
         // TODO:
         // Retrieve all orders of a user
+        List<Order> orders = new ArrayList<>();
+        String sql = "SELECT id, user_id, created_at, total_price FROM orders WHERE user_id = ?";
 
-        return null;
+        try (Connection conn = DatabaseConnection.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql)) {
+
+            stmt.setInt(1, userId);
+
+            try (ResultSet rs = stmt.executeQuery()) {
+                while (rs.next()) {
+                    int id = rs.getInt("id");
+                    int uId = rs.getInt("user_id");
+                    Timestamp createdAt = rs.getTimestamp("created_at");
+                    BigDecimal totalPrice = rs.getBigDecimal("total_price");
+
+                    orders.add(new Order(id, uId, createdAt.toLocalDateTime(), totalPrice));
+                }
+            }
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+
+        return orders;
     }
 
 }

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

@@ -1,7 +1,14 @@
 package dev.dao;
 
 import dev.model.OrderDetail;
+import dev.database.DatabaseConnection;
 
+import java.math.BigDecimal;
+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 {
@@ -10,15 +17,52 @@ public class OrderDetailDao {
 
         // TODO:
         // Insert order detail
+        String sql = "INSERT INTO order_details (order_id, menu_item_id, quantity, unit_price) VALUES (?, ?, ?, ?)";
 
+        try (Connection conn = DatabaseConnection.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql)) {
+
+            stmt.setInt(1, detail.getOrderId());
+            stmt.setInt(2, detail.getMenuItemId());
+            stmt.setInt(3, detail.getQuantity());
+            stmt.setBigDecimal(4, detail.getPrice());
+
+            stmt.executeUpdate();
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
     }
 
     public List<OrderDetail> findByOrderId(int orderId) {
 
         // TODO:
         // Retrieve order details
+        List<OrderDetail> details = new ArrayList<>();
+        String sql = "SELECT id, order_id, menu_item_id, quantity, unit_price FROM order_details WHERE order_id = ?";
 
-        return null;
+        try (Connection conn = DatabaseConnection.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql)) {
+
+            stmt.setInt(1, orderId);
+
+            try (ResultSet rs = stmt.executeQuery()) {
+                while (rs.next()) {
+                    int id = rs.getInt("id");
+                    int oId = rs.getInt("order_id");
+                    int menuItemId = rs.getInt("menu_item_id");
+                    int quantity = rs.getInt("quantity");
+                    BigDecimal price = rs.getBigDecimal("unit_price");
+
+                    details.add(new OrderDetail(id, oId, menuItemId, quantity, price));
+                }
+            }
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+
+        return details;
     }
 
 }

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

@@ -1,21 +1,61 @@
 package dev.dao;
 
 import dev.model.User;
+import dev.database.DatabaseConnection;
 
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
 public class UserDao {
 
     public boolean save(User user) {
 
         // TODO:
         // Insert user into database
+        String sql = "INSERT INTO users (username, password_hash, email) VALUES (?, ?, ?)";
 
-        return false;
+        try (Connection conn = DatabaseConnection.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql)) {
+
+            stmt.setString(1, user.getUsername());
+            stmt.setString(2, user.getPassword());
+            stmt.setString(3, user.getEmail());
+
+            stmt.executeUpdate();
+            return true;
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+            return false;
+        }
     }
 
     public User findByUsername(String username) {
 
         // TODO:
         // Find a user by username
+        String sql = "SELECT id, username, password_hash, email FROM users WHERE username = ?";
+
+        try (Connection conn = DatabaseConnection.getConnection();
+             PreparedStatement stmt = conn.prepareStatement(sql)) {
+
+            stmt.setString(1, username);
+
+            try (ResultSet rs = stmt.executeQuery()) {
+                if (rs.next()) {
+                    int id = rs.getInt("id");
+                    String uname = rs.getString("username");
+                    String passwordHash = rs.getString("password_hash");
+                    String email = rs.getString("email");
+
+                    return new User(id, uname, passwordHash, email);
+                }
+            }
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
 
         return null;
     }

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

@@ -1,15 +1,16 @@
 package dev.database;
 
 import java.sql.Connection;
+import java.sql.DriverManager;
 import java.sql.SQLException;
 
 public class DatabaseConnection {
+    private static final String URL = "jdbc:postgresql://localhost:5432/restaurant_db";
 
-    private static final String URL = "jdbc:postgresql://localhost:5432/restaurant_db"; // DB Server
+    private static final String USER = "avasanatkar";
 
-    private static final String USER = "postgres"; // Your Username
+    private static final String PASSWORD = "";
 
-    private static final String PASSWORD = "password"; // Your Password
 
     private DatabaseConnection() {
 
@@ -21,7 +22,9 @@ public class DatabaseConnection {
         // TODO:
         // Return a valid PostgreSQL connection
 
-        return null;
+       // return null;
+        return DriverManager.getConnection(URL, USER, PASSWORD);
+
     }
 
 }

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

@@ -1,15 +1,45 @@
 package dev.model;
 
+import java.math.BigDecimal;
+
 public class MenuItem {
 
     private int id;
-
     private String name;
-
     private String description;
-
-    private double price;
-
+    private BigDecimal price;
     private String category;
 
+    public MenuItem() {}
+
+    public MenuItem(int id, String name, String description, BigDecimal price, String category) {
+        this.id = id;
+        this.name = name;
+        this.description = description;
+        this.price = price;
+        this.category = category;
+    }
+
+    public MenuItem(String name, String description, BigDecimal price, String category) {
+        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 BigDecimal getPrice() { return price; }
+    public void setPrice(BigDecimal price) { this.price = price; }
+    public String getCategory() { return category; }
+    public void setCategory(String category) { this.category = category; }
+
+    @Override
+    public String toString() {
+        return id + ". " + name + " - $" + price + (category != null ? " (" + category + ")" : "");
+    }
 }

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

@@ -1,15 +1,40 @@
 package dev.model;
 
+import java.math.BigDecimal;
 import java.time.LocalDateTime;
 
 public class Order {
 
     private int id;
-
     private int userId;
-
     private LocalDateTime createdAt;
+    private BigDecimal totalPrice;
 
-    private double totalPrice;
+    public Order() {}
 
+    public Order(int id, int userId, LocalDateTime createdAt, BigDecimal totalPrice) {
+        this.id = id;
+        this.userId = userId;
+        this.createdAt = createdAt;
+        this.totalPrice = totalPrice;
+    }
+
+    public Order(int userId, BigDecimal totalPrice) {
+        this.userId = userId;
+        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 BigDecimal getTotalPrice() { return totalPrice; }
+    public void setTotalPrice(BigDecimal totalPrice) { this.totalPrice = totalPrice; }
+
+    @Override
+    public String toString() {
+        return "Order #" + id + " - " + createdAt + " - Total: $" + totalPrice;
+    }
 }

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

@@ -1,15 +1,44 @@
 package dev.model;
 
+import java.math.BigDecimal;
+
 public class OrderDetail {
 
     private int id;
-
     private int orderId;
-
     private int menuItemId;
-
     private int quantity;
+    private BigDecimal price;
 
-    private double price;
+    public OrderDetail() {}
 
+    public OrderDetail(int id, int orderId, int menuItemId, int quantity, BigDecimal price) {
+        this.id = id;
+        this.orderId = orderId;
+        this.menuItemId = menuItemId;
+        this.quantity = quantity;
+        this.price = price;
+    }
+
+    public OrderDetail(int orderId, int menuItemId, int quantity, BigDecimal price) {
+        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 BigDecimal getPrice() { return price; }
+    public void setPrice(BigDecimal price) { this.price = price; }
+
+    public BigDecimal getSubtotal() {
+        return price.multiply(BigDecimal.valueOf(quantity));
+    }
 }

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

@@ -3,11 +3,36 @@ package dev.model;
 public class User {
 
     private int id;
-
     private String username;
-
     private String password;
-
     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 User(String username, String password, String email) {
+        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; }
+
+    @Override
+    public String toString() {
+        return "User{id=" + id + ", username='" + username + "', email='" + email + "'}";
+    }
 }

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

@@ -1,21 +1,42 @@
 package dev.service;
 
 import dev.model.User;
+import dev.dao.UserDao;
+import org.mindrot.jbcrypt.BCrypt;
 
 public class AuthService {
-
+    private final UserDao userDao = new UserDao();
     public boolean register(String username, String password, String email) {
 
         // TODO:
         // Validate and register user
+        if (username == null || username.isBlank() || password == null || password.isBlank()) {
+            return false;
+        }
 
-        return false;
+        if (userDao.findByUsername(username) != null) {
+            return false;
+        }
+
+        String hashedPassword = BCrypt.hashpw(password, BCrypt.gensalt());
+        User newUser = new User(username, hashedPassword, email);
+
+        return userDao.save(newUser);
     }
 
     public User login(String username, String password) {
 
         // TODO:
         // Authenticate user
+        User user = userDao.findByUsername(username);
+
+        if (user == null) {
+            return null;
+        }
+
+        if (BCrypt.checkpw(password, user.getPassword())) {
+            return user;
+        }
 
         return null;
     }

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

@@ -1,12 +1,30 @@
 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> items = menuItemDao.findAll();
 
+        if (items.isEmpty()) {
+            System.out.println("No menu items available.");
+            return;
+        }
+
+        System.out.println("=======================================");
+        System.out.println("          MENU");
+        System.out.println("=======================================");
+
+        for (MenuItem item : items) {
+            System.out.println(item);
+        }
+
+        System.out.println("=======================================");
     }
 
 }

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

@@ -1,26 +1,108 @@
 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.math.BigDecimal;
+import java.util.List;
+import java.util.Map;
 public class OrderService {
+    private final OrderDao orderDao = new OrderDao();
+    private final OrderDetailDao orderDetailDao = new OrderDetailDao();
+    private final MenuItemDao menuItemDao = new MenuItemDao();
 
-    public void placeOrder(int userId) {
+    public int placeOrder(int userId, Map<Integer, Integer> itemQuantities) {
 
         // TODO:
         // Create order
 
+        if (itemQuantities == null || itemQuantities.isEmpty()) {
+            return -1;
+        }
+
+        BigDecimal total = BigDecimal.ZERO;
+
+        for (Map.Entry<Integer, Integer> entry : itemQuantities.entrySet()) {
+            MenuItem item = menuItemDao.findById(entry.getKey());
+            if (item == null) {
+                continue;
+            }
+            int quantity = entry.getValue();
+            total = total.add(item.getPrice().multiply(BigDecimal.valueOf(quantity)));
+        }
+
+        Order order = new Order(userId, total);
+        int orderId = orderDao.save(order);
+
+        if (orderId == -1) {
+            return -1;
+        }
+
+        for (Map.Entry<Integer, Integer> entry : itemQuantities.entrySet()) {
+            MenuItem item = menuItemDao.findById(entry.getKey());
+            if (item == null) {
+                continue;
+            }
+            int quantity = entry.getValue();
+
+            OrderDetail detail = new OrderDetail(orderId, item.getId(), quantity, item.getPrice());
+            orderDetailDao.save(detail);
+        }
+
+        return orderId;
     }
 
     public void printReceipt(int orderId) {
 
         // TODO:
         // Print order receipt
+        List<OrderDetail> details = orderDetailDao.findByOrderId(orderId);
 
+        if (details.isEmpty()) {
+            System.out.println("No details found for order #" + orderId);
+            return;
+        }
+
+        System.out.println("---------------------------------------");
+        System.out.printf("%-12s %-6s %-10s %-10s%n", "Item", "Qty", "Unit", "Total");
+        System.out.println("---------------------------------------");
+
+        BigDecimal grandTotal = BigDecimal.ZERO;
+
+        for (OrderDetail detail : details) {
+            MenuItem item = menuItemDao.findById(detail.getMenuItemId());
+            String name = (item != null) ? item.getName() : "Unknown item";
+            BigDecimal subtotal = detail.getSubtotal();
+            grandTotal = grandTotal.add(subtotal);
+
+            System.out.printf("%-12s %-6d $%-9.2f $%-9.2f%n",
+                    name, detail.getQuantity(), detail.getPrice(), subtotal);
+        }
+
+        System.out.println("---------------------------------------");
+        System.out.println("Final Total: $" + grandTotal);
     }
 
     public void showOrderHistory(int userId) {
 
         // TODO:
         // Display user's order history
+        List<Order> orders = orderDao.findByUserId(userId);
 
+        if (orders.isEmpty()) {
+            System.out.println("No past orders found.");
+            return;
+        }
+
+        System.out.println("=======================================");
+        System.out.println("          ORDER HISTORY");
+        System.out.println("=======================================");
+
+        for (Order order : orders) {
+            System.out.println(order);
+        }
     }
-
 }

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

@@ -1,12 +1,23 @@
 package dev.ui;
 
 import java.util.Scanner;
+import dev.model.MenuItem;
+import dev.model.User;
+import dev.service.AuthService;
+import dev.service.MenuService;
+import dev.service.OrderService;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 
 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
+                    handleLogin();
                     break;
 
                 case 2:
                     // TODO
+                    handleRegister();
                     break;
 
                 case 3:
@@ -40,5 +53,138 @@ public class ConsoleMenu {
         }
 
     }
+    private void handleRegister() {
+
+        System.out.println();
+        System.out.println("[Register New Account]");
+        System.out.print("Choose a username: ");
+        String username = scanner.next();
+        System.out.print("Choose a password: ");
+        String password = scanner.next();
+        scanner.nextLine();
+        System.out.print("Email (optional, press enter to skip): ");
+        String email = scanner.nextLine();
+
+        if (email.isBlank()) {
+            email = null;
+        }
+
+        boolean success = authService.register(username, password, email);
+
+        if (success) {
+            System.out.println("Registration successful! You can now login.");
+        } else {
+            System.out.println("Registration failed. Username may already be taken.");
+        }
+    }
+
+    private void handleLogin() {
+
+        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("Invalid username or password.");
+            return;
+        }
+
+        System.out.println("Welcome, " + user.getUsername() + "!");
+        showMainMenu(user);
+    }
+
+    private void showMainMenu(User user) {
+
+        boolean loggedIn = true;
+
+        while (loggedIn) {
+
+            System.out.println();
+            System.out.println("=======================================");
+            System.out.println("          MAIN MENU");
+            System.out.println("=======================================");
+            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:
+                    handlePlaceOrder(user);
+                    break;
+
+                case 3:
+                    orderService.showOrderHistory(user.getId());
+                    break;
+
+                case 4:
+                    loggedIn = false;
+                    System.out.println("Logged out.");
+                    break;
+
+                default:
+                    System.out.println("Invalid choice");
+            }
+        }
+    }
+
+    private void handlePlaceOrder(User user) {
+
+        menuService.showMenu();
+
+        Map<Integer, Integer> itemQuantities = new HashMap<>();
+
+        System.out.println();
+        System.out.println("[Placing Order]");
+
+        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;
+            }
+
+            System.out.print("Enter quantity: ");
+            int quantity = scanner.nextInt();
+
+            if (quantity <= 0) {
+                System.out.println("Quantity must be greater than zero.");
+                continue;
+            }
+
+            itemQuantities.merge(itemId, quantity, Integer::sum);
+            System.out.println("Added " + quantity + "x item #" + itemId + " to your cart.");
+        }
+
+        if (itemQuantities.isEmpty()) {
+            System.out.println("No items added. Order cancelled.");
+            return;
+        }
+
+        int orderId = orderService.placeOrder(user.getId(), itemQuantities);
+
+        if (orderId == -1) {
+            System.out.println("Failed to place order.");
+            return;
+        }
+
+        System.out.println();
+        System.out.println("[Order Summary / Receipt]");
+        orderService.printReceipt(orderId);
+        System.out.println("Order saved successfully!");
+    }
 
 }