import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;

// 图书类
class Book {
    private String id;
    private String title;
    private String author;
    private String isbn;
    private String category;
    private boolean available;

    public Book(String id, String title, String author, String isbn, String category) {
        this.id = id;
        this.title = title;
        this.author = author;
        this.isbn = isbn;
        this.category = category;
        this.available = true;
    }

    // Getter和Setter方法
    public String getId() { return id; }
    public void setId(String id) { this.id = id; }
    
    public String getTitle() { return title; }
    public void setTitle(String title) { this.title = title; }
    
    public String getAuthor() { return author; }
    public void setAuthor(String author) { this.author = author; }
    
    public String getIsbn() { return isbn; }
    public void setIsbn(String isbn) { this.isbn = isbn; }
    
    public String getCategory() { return category; }
    public void setCategory(String category) { this.category = category; }
    
    public boolean isAvailable() { return available; }
    public void setAvailable(boolean available) { this.available = available; }
    
    @Override
    public String toString() {
        return "ID: " + id + ", 书名: " + title + ", 作者: " + author + 
               ", ISBN: " + isbn + ", 类别: " + category + 
               ", 状态: " + (available ? "可借" : "已借出");
    }
}

// 用户类
class User {
    private String username;
    private String password;
    private String email;
    
    public User(String username, String password, String email) {
        this.username = username;
        this.password = password;
        this.email = email;
    }
    
    // Getter和Setter方法
    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; }
}

// 图书管理系统类
class LibraryManagementSystem {
    private List<Book> books;
    private List<User> users;
    private User currentUser;
    
    public LibraryManagementSystem() {
        books = new ArrayList<>();
        users = new ArrayList<>();
        // 添加一些初始图书
        books.add(new Book("B001", "Java编程思想", "Bruce Eckel", "9787111213826", "编程"));
        books.add(new Book("B002", "设计模式", "Erich Gamma", "9787111075647", "编程"));
        books.add(new Book("B003", "算法导论", "Thomas H. Cormen", "9787111407010", "算法"));
    }
    
    // 用户注册
    public boolean registerUser(String username, String password, String email) {
        // 检查用户名是否已存在
        for (User user : users) {
            if (user.getUsername().equals(username)) {
                return false;
            }
        }
        
        users.add(new User(username, password, email));
        return true;
    }
    
    // 用户登录
    public boolean loginUser(String username, String password) {
        for (User user : users) {
            if (user.getUsername().equals(username) && user.getPassword().equals(password)) {
                currentUser = user;
                return true;
            }
        }
        return false;
    }
    
    // 获取当前用户
    public User getCurrentUser() {
        return currentUser;
    }
    
    // 添加图书
    public boolean addBook(Book book) {
        // 检查ID是否已存在
        for (Book b : books) {
            if (b.getId().equals(book.getId())) {
                return false;
            }
        }
        books.add(book);
        return true;
    }
    
    // 删除图书
    public boolean deleteBook(String bookId) {
        for (int i = 0; i < books.size(); i++) {
            if (books.get(i).getId().equals(bookId)) {
                books.remove(i);
                return true;
            }
        }
        return false;
    }
    
    // 更新图书
    public boolean updateBook(String bookId, Book updatedBook) {
        for (int i = 0; i < books.size(); i++) {
            if (books.get(i).getId().equals(bookId)) {
                books.set(i, updatedBook);
                return true;
            }
        }
        return false;
    }
    
    // 查找图书
    public List<Book> searchBooks(String keyword) {
        List<Book> result = new ArrayList<>();
        for (Book book : books) {
            if (book.getTitle().contains(keyword) || 
                book.getAuthor().contains(keyword) || 
                book.getCategory().contains(keyword) ||
                book.getId().contains(keyword)) {
                result.add(book);
            }
        }
        return result;
    }
    
    // 获取所有图书
    public List<Book> getAllBooks() {
        return new ArrayList<>(books);
    }
    
    // 根据ID获取图书
    public Book getBookById(String bookId) {
        for (Book book : books) {
            if (book.getId().equals(bookId)) {
                return book;
            }
        }
        return null;
    }
}

// 主界面
public class LibrarySystemGUI extends JFrame {
    private LibraryManagementSystem librarySystem;
    private JPanel mainPanel;
    private CardLayout cardLayout;
    
    // 登录面板组件
    private JTextField loginUsernameField;
    private JPasswordField loginPasswordField;
    
    // 注册面板组件
    private JTextField registerUsernameField;
    private JPasswordField registerPasswordField;
    private JTextField registerEmailField;
    
    // 主功能面板组件
    private JTextArea bookListArea;
    private JTextField searchField;
    private DefaultListModel<String> bookListModel;
    private JList<String> bookList;
    
    public LibrarySystemGUI() {
        librarySystem = new LibraryManagementSystem();
        initializeGUI();
    }
    
    private void initializeGUI() {
        setTitle("图书管理系统");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(800, 600);
        setLocationRelativeTo(null);
        
        // 创建主面板和卡片布局
        cardLayout = new CardLayout();
        mainPanel = new JPanel(cardLayout);
        
        // 添加各个面板
        mainPanel.add(createLoginPanel(), "login");
        mainPanel.add(createRegisterPanel(), "register");
        mainPanel.add(createMainPanel(), "main");
        
        add(mainPanel);
        cardLayout.show(mainPanel, "login");
        
        setVisible(true);
    }
    
    // 创建登录面板
    private JPanel createLoginPanel() {
        JPanel panel = new JPanel(new BorderLayout());
        panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
        
        // 标题
        JLabel titleLabel = new JLabel("图书管理系统", JLabel.CENTER);
        titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 24));
        panel.add(titleLabel, BorderLayout.NORTH);
        
        // 表单面板
        JPanel formPanel = new JPanel(new GridLayout(3, 2, 10, 10));
        formPanel.setBorder(BorderFactory.createEmptyBorder(50, 100, 50, 100));
        
        JLabel usernameLabel = new JLabel("用户名:");
        loginUsernameField = new JTextField();
        JLabel passwordLabel = new JLabel("密码:");
        loginPasswordField = new JPasswordField();
        
        formPanel.add(usernameLabel);
        formPanel.add(loginUsernameField);
        formPanel.add(passwordLabel);
        formPanel.add(loginPasswordField);
        
        // 按钮面板
        JPanel buttonPanel = new JPanel(new FlowLayout());
        JButton loginButton = new JButton("登录");
        JButton registerButton = new JButton("注册");
        
        loginButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                String username = loginUsernameField.getText();
                String password = new String(loginPasswordField.getPassword());
                
                if (username.isEmpty() || password.isEmpty()) {
                    JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                        "用户名和密码不能为空!", "错误", JOptionPane.ERROR_MESSAGE);
                    return;
                }
                
                if (librarySystem.loginUser(username, password)) {
                    JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                        "登录成功!", "成功", JOptionPane.INFORMATION_MESSAGE);
                    refreshBookList();
                    cardLayout.show(mainPanel, "main");
                } else {
                    JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                        "用户名或密码错误!", "错误", JOptionPane.ERROR_MESSAGE);
                }
            }
        });
        
        registerButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                cardLayout.show(mainPanel, "register");
            }
        });
        
        buttonPanel.add(loginButton);
        buttonPanel.add(registerButton);
        
        formPanel.add(new JLabel()); // 占位
        formPanel.add(buttonPanel);
        
        panel.add(formPanel, BorderLayout.CENTER);
        
        return panel;
    }
    
    // 创建注册面板
    private JPanel createRegisterPanel() {
        JPanel panel = new JPanel(new BorderLayout());
        panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
        
        // 标题
        JLabel titleLabel = new JLabel("用户注册", JLabel.CENTER);
        titleLabel.setFont(new Font("微软雅黑", Font.BOLD, 24));
        panel.add(titleLabel, BorderLayout.NORTH);
        
        // 表单面板
        JPanel formPanel = new JPanel(new GridLayout(4, 2, 10, 10));
        formPanel.setBorder(BorderFactory.createEmptyBorder(50, 100, 50, 100));
        
        JLabel usernameLabel = new JLabel("用户名:");
        registerUsernameField = new JTextField();
        JLabel passwordLabel = new JLabel("密码:");
        registerPasswordField = new JPasswordField();
        JLabel emailLabel = new JLabel("邮箱:");
        registerEmailField = new JTextField();
        
        formPanel.add(usernameLabel);
        formPanel.add(registerUsernameField);
        formPanel.add(passwordLabel);
        formPanel.add(registerPasswordField);
        formPanel.add(emailLabel);
        formPanel.add(registerEmailField);
        
        // 按钮面板
        JPanel buttonPanel = new JPanel(new FlowLayout());
        JButton registerButton = new JButton("注册");
        JButton backButton = new JButton("返回登录");
        
        registerButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                String username = registerUsernameField.getText();
                String password = new String(registerPasswordField.getPassword());
                String email = registerEmailField.getText();
                
                if (username.isEmpty() || password.isEmpty() || email.isEmpty()) {
                    JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                        "所有字段都不能为空!", "错误", JOptionPane.ERROR_MESSAGE);
                    return;
                }
                
                if (librarySystem.registerUser(username, password, email)) {
                    JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                        "注册成功! 请登录.", "成功", JOptionPane.INFORMATION_MESSAGE);
                    cardLayout.show(mainPanel, "login");
                } else {
                    JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                        "用户名已存在!", "错误", JOptionPane.ERROR_MESSAGE);
                }
            }
        });
        
        backButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                cardLayout.show(mainPanel, "login");
            }
        });
        
        buttonPanel.add(registerButton);
        buttonPanel.add(backButton);
        
        formPanel.add(new JLabel()); // 占位
        formPanel.add(buttonPanel);
        
        panel.add(formPanel, BorderLayout.CENTER);
        
        return panel;
    }
    
    // 创建主功能面板
    private JPanel createMainPanel() {
        JPanel panel = new JPanel(new BorderLayout());
        
        // 顶部面板 - 欢迎信息和搜索
        JPanel topPanel = new JPanel(new BorderLayout());
        topPanel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
        
        JLabel welcomeLabel = new JLabel("欢迎使用图书管理系统");
        welcomeLabel.setFont(new Font("微软雅黑", Font.BOLD, 18));
        topPanel.add(welcomeLabel, BorderLayout.WEST);
        
        JPanel searchPanel = new JPanel(new FlowLayout());
        searchField = new JTextField(20);
        JButton searchButton = new JButton("搜索");
        JButton logoutButton = new JButton("退出登录");
        
        searchButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                String keyword = searchField.getText();
                if (keyword.isEmpty()) {
                    refreshBookList();
                } else {
                    List<Book> searchResult = librarySystem.searchBooks(keyword);
                    updateBookList(searchResult);
                }
            }
        });
        
        logoutButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                int result = JOptionPane.showConfirmDialog(LibrarySystemGUI.this, 
                    "确定要退出登录吗?", "确认", JOptionPane.YES_NO_OPTION);
                if (result == JOptionPane.YES_OPTION) {
                    cardLayout.show(mainPanel, "login");
                    // 清空登录信息
                    loginUsernameField.setText("");
                    loginPasswordField.setText("");
                }
            }
        });
        
        searchPanel.add(new JLabel("搜索:"));
        searchPanel.add(searchField);
        searchPanel.add(searchButton);
        searchPanel.add(logoutButton);
        
        topPanel.add(searchPanel, BorderLayout.EAST);
        panel.add(topPanel, BorderLayout.NORTH);
        
        // 中央面板 - 图书列表
        JPanel centerPanel = new JPanel(new BorderLayout());
        centerPanel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
        
        bookListModel = new DefaultListModel<>();
        bookList = new JList<>(bookListModel);
        JScrollPane scrollPane = new JScrollPane(bookList);
        
        centerPanel.add(new JLabel("图书列表:"), BorderLayout.NORTH);
        centerPanel.add(scrollPane, BorderLayout.CENTER);
        
        panel.add(centerPanel, BorderLayout.CENTER);
        
        // 底部面板 - 功能按钮
        JPanel bottomPanel = new JPanel(new FlowLayout());
        bottomPanel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
        
        JButton addButton = new JButton("添加图书");
        JButton editButton = new JButton("编辑图书");
        JButton deleteButton = new JButton("删除图书");
        JButton refreshButton = new JButton("刷新列表");
        
        addButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                showAddBookDialog();
            }
        });
        
        editButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                int selectedIndex = bookList.getSelectedIndex();
                if (selectedIndex == -1) {
                    JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                        "请先选择一本图书!", "提示", JOptionPane.WARNING_MESSAGE);
                    return;
                }
                
                String selectedBookInfo = bookListModel.getElementAt(selectedIndex);
                String bookId = selectedBookInfo.split(",")[0].split(":")[1].trim();
                
                Book book = librarySystem.getBookById(bookId);
                if (book != null) {
                    showEditBookDialog(book);
                }
            }
        });
        
        deleteButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                int selectedIndex = bookList.getSelectedIndex();
                if (selectedIndex == -1) {
                    JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                        "请先选择一本图书!", "提示", JOptionPane.WARNING_MESSAGE);
                    return;
                }
                
                String selectedBookInfo = bookListModel.getElementAt(selectedIndex);
                String bookId = selectedBookInfo.split(",")[0].split(":")[1].trim();
                
                int result = JOptionPane.showConfirmDialog(LibrarySystemGUI.this, 
                    "确定要删除这本图书吗?", "确认删除", JOptionPane.YES_NO_OPTION);
                
                if (result == JOptionPane.YES_OPTION) {
                    if (librarySystem.deleteBook(bookId)) {
                        JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                            "图书删除成功!", "成功", JOptionPane.INFORMATION_MESSAGE);
                        refreshBookList();
                    } else {
                        JOptionPane.showMessageDialog(LibrarySystemGUI.this, 
                            "图书删除失败!", "错误", JOptionPane.ERROR_MESSAGE);
                    }
                }
            }
        });
        
        refreshButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                refreshBookList();
            }
        });
        
        bottomPanel.add(addButton);
        bottomPanel.add(editButton);
        bottomPanel.add(deleteButton);
        bottomPanel.add(refreshButton);
        
        panel.add(bottomPanel, BorderLayout.SOUTH);
        
        return panel;
    }
    
    // 显示添加图书对话框
    private void showAddBookDialog() {
        JTextField idField = new JTextField();
        JTextField titleField = new JTextField();
        JTextField authorField = new JTextField();
        JTextField isbnField = new JTextField();
        JTextField categoryField = new JTextField();
        
        JPanel panel = new JPanel(new GridLayout(5, 2, 10, 10));
        panel.add(new JLabel("图书ID:"));
        panel.add(idField);
        panel.add(new JLabel("书名:"));
        panel.add(titleField);
        panel.add(new JLabel("作者:"));
        panel.add(authorField);
        panel.add(new JLabel("ISBN:"));
        panel.add(isbnField);
        panel.add(new JLabel("类别:"));
        panel.add(categoryField);
        
        int result = JOptionPane.showConfirmDialog(this, panel, "添加图书", 
            JOptionPane.OK_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE);
        
        if (result == JOptionPane.OK_OPTION) {
            String id = idField.getText();
            String title = titleField.getText();
            String author = authorField.getText();
            String isbn = isbnField.getText();
            String category = categoryField.getText();
            
            if (id.isEmpty() || title.isEmpty() || author.isEmpty() || 
                isbn.isEmpty() || category.isEmpty()) {
                JOptionPane.showMessageDialog(this, "所有字段都不能为空!", "错误", JOptionPane.ERROR_MESSAGE);
                return;
            }
            
            Book newBook = new Book(id, title, author, isbn, category);
            if (librarySystem.addBook(newBook)) {
                JOptionPane.showMessageDialog(this, "图书添加成功!", "成功", JOptionPane.INFORMATION_MESSAGE);
                refreshBookList();
            } else {
                JOptionPane.showMessageDialog(this, "图书ID已存在!", "错误", JOptionPane.ERROR_MESSAGE);
            }
        }
    }
    
    // 显示编辑图书对话框
    private void showEditBookDialog(Book book) {
        JTextField idField = new JTextField(book.getId());
        idField.setEditable(false); // ID不可编辑
        JTextField titleField = new JTextField(book.getTitle());
        JTextField authorField = new JTextField(book.getAuthor());
        JTextField isbnField = new JTextField(book.getIsbn());
        JTextField categoryField = new JTextField(book.getCategory());
        
        JPanel panel = new JPanel(new GridLayout(5, 2, 10, 10));
        panel.add(new JLabel("图书ID:"));
        panel.add(idField);
        panel.add(new JLabel("书名:"));
        panel.add(titleField);
        panel.add(new JLabel("作者:"));
        panel.add(authorField);
        panel.add(new JLabel("ISBN:"));
        panel.add(isbnField);
        panel.add(new JLabel("类别:"));
        panel.add(categoryField);
        
        int result = JOptionPane.showConfirmDialog(this, panel, "编辑图书", 
            JOptionPane.OK_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE);
        
        if (result == JOptionPane.OK_OPTION) {
            String title = titleField.getText();
            String author = authorField.getText();
            String isbn = isbnField.getText();
            String category = categoryField.getText();
            
            if (title.isEmpty() || author.isEmpty() || isbn.isEmpty() || category.isEmpty()) {
                JOptionPane.showMessageDialog(this, "所有字段都不能为空!", "错误", JOptionPane.ERROR_MESSAGE);
                return;
            }
            
            Book updatedBook = new Book(book.getId(), title, author, isbn, category);
            updatedBook.setAvailable(book.isAvailable());
            
            if (librarySystem.updateBook(book.getId(), updatedBook)) {
                JOptionPane.showMessageDialog(this, "图书更新成功!", "成功", JOptionPane.INFORMATION_MESSAGE);
                refreshBookList();
            } else {
                JOptionPane.showMessageDialog(this, "图书更新失败!", "错误", JOptionPane.ERROR_MESSAGE);
            }
        }
    }
    
    // 刷新图书列表
    private void refreshBookList() {
        List<Book> books = librarySystem.getAllBooks();
        updateBookList(books);
    }
    
    // 更新图书列表显示
    private void updateBookList(List<Book> books) {
        bookListModel.clear();
        for (Book book : books) {
            bookListModel.addElement(book.toString());
        }
    }
    
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new LibrarySystemGUI();
            }
        });
    }
}