AddBook.java

import javax.swing.*;
import java.awt.*;
import java.sql.*;

public class AddBook extends JFrame {
    JTextField name;
    JTextField author;
    JTextArea info;

    AddBook() {
        setTitle("Add Book");
        setSize(520, 360);
        setLocationRelativeTo(null);
        setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

        JPanel root = LibraryUI.createContentPanel();
        root.setLayout(new BorderLayout(0, 16));
        setContentPane(root);

        JPanel header = new JPanel();
        header.setOpaque(false);
        header.setLayout(new BoxLayout(header, BoxLayout.Y_AXIS));
        header.add(LibraryUI.createTitle("Add Book"));
        header.add(Box.createVerticalStrut(4));
        header.add(LibraryUI.createSubtitle("Create a new library record and avoid duplicate entries."));
        root.add(header, BorderLayout.NORTH);

        JPanel card = LibraryUI.createCardPanel();
        card.setLayout(new BoxLayout(card, BoxLayout.Y_AXIS));
        root.add(card, BorderLayout.CENTER);

        JLabel nameLabel = new JLabel("Book Name");
        nameLabel.setFont(LibraryUI.LABEL_FONT);
        nameLabel.setForeground(LibraryUI.TEXT);
        card.add(nameLabel);
        card.add(Box.createVerticalStrut(8));

        name = LibraryUI.createTextField(26);
        card.add(name);
        card.add(Box.createVerticalStrut(14));

        JLabel authorLabel = new JLabel("Author");
        authorLabel.setFont(LibraryUI.LABEL_FONT);
        authorLabel.setForeground(LibraryUI.TEXT);
        card.add(authorLabel);
        card.add(Box.createVerticalStrut(8));

        author = LibraryUI.createTextField(26);
        card.add(author);
        card.add(Box.createVerticalStrut(16));

        JPanel buttonRow = new JPanel(new FlowLayout(FlowLayout.LEFT, 0, 0));
        buttonRow.setOpaque(false);
        JButton addBtn = LibraryUI.createPrimaryButton("Add Book");
        buttonRow.add(addBtn);
        card.add(buttonRow);
        card.add(Box.createVerticalStrut(16));

        info = LibraryUI.createInfoArea(5, 30);
        info.setText("Enter a book name and author. If the same book already exists, the app will show it instead of adding another copy.");
        card.add(LibraryUI.wrap(info));

        addBtn.addActionListener(e -> addBook());

        setVisible(true);
    }

    private void addBook() {
        String bookName = name.getText().trim();
        String authorName = author.getText().trim();

        if (bookName.isEmpty() || authorName.isEmpty()) {
            JOptionPane.showMessageDialog(this, "Please enter both book name and author.");
            return;
        }

        Connection con = DBConnection.getConnection();
        if (con == null) {
            return;
        }

        try (
            PreparedStatement check = con.prepareStatement(
                "SELECT * FROM books WHERE LOWER(name)=LOWER(?) AND LOWER(author)=LOWER(?)"
            );
            PreparedStatement insert = con.prepareStatement(
                "INSERT INTO books(name, author, issued) VALUES(?,?,false)"
            )
        ) {
            check.setString(1, bookName);
            check.setString(2, authorName);
            ResultSet existing = check.executeQuery();

            if (existing.next()) {
                info.setText(
                    "This book already exists.\n\n"
                        + "ID: " + existing.getInt("id") + "\n"
                        + "Name: " + existing.getString("name") + "\n"
                        + "Author: " + existing.getString("author") + "\n"
                        + "Status: " + (existing.getBoolean("issued") ? "Issued" : "Available")
                );
                JOptionPane.showMessageDialog(this, "This book already exists in the library.");
                return;
            }

            insert.setString(1, bookName);
            insert.setString(2, authorName);
            int rows = insert.executeUpdate();

            if (rows > 0) {
                info.setText("Book added successfully.\n\nName: " + bookName + "\nAuthor: " + authorName + "\nStatus: Available");
                name.setText("");
                author.setText("");
                JOptionPane.showMessageDialog(this, "Book added successfully.");
            } else {
                info.setText("Book could not be added.");
            }
        } catch (Exception ex) {
            JOptionPane.showMessageDialog(this, "Unable to add book.\n" + ex.getMessage());
        }
    }
}