MainScreen.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

/**
 * MainScreen class - Main ATM interface after login
 */
public class MainScreen extends JFrame {
    private BankAccount currentAccount;
    private BasicATM atm;
    private JLabel balanceLabel;
    private JLabel accountTypeLabel;
    private JLabel accountNumberLabel;

    public MainScreen(BankAccount account) {
        this.currentAccount = account;
        this.atm = BasicATM.getInstance();

        setTitle("ATM Simulation - Main Menu");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(600, 400);
        setLocationRelativeTo(null);

        JPanel mainPanel = new JPanel(new BorderLayout(10, 10));
        mainPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));

        // Header section
        JPanel headerPanel = new JPanel(new GridLayout(3, 1));
        accountTypeLabel = new JLabel("Account Type: " + account.getAccountType());
        accountTypeLabel.setFont(new Font("Arial", Font.BOLD, 16));

        String maskedNumber = "xxxx-xxxx-xxxx-" + account.getAccountNumber().substring(12);
        accountNumberLabel = new JLabel("Account: " + maskedNumber);

        balanceLabel = new JLabel("Balance: $" + String.format("%.2f", account.getBalance()));
        balanceLabel.setFont(new Font("Arial", Font.BOLD, 16));

        headerPanel.add(accountTypeLabel);
        headerPanel.add(accountNumberLabel);
        headerPanel.add(balanceLabel);

        // Button section
        JPanel buttonPanel = new JPanel(new GridLayout(2, 2, 10, 10));
        JButton checkBalanceButton = createMenuButton("Check Balance");
        JButton withdrawButton = createMenuButton("Withdraw Cash");
        JButton depositButton = createMenuButton("Deposit Funds");
        JButton historyButton = createMenuButton("Transaction History");

        buttonPanel.add(checkBalanceButton);
        buttonPanel.add(withdrawButton);
        buttonPanel.add(depositButton);
        buttonPanel.add(historyButton);

        // Footer section
        JPanel footerPanel = new JPanel(new FlowLayout(FlowLayout.RIGHT));
        JButton logoutButton = new JButton("Logout");
        footerPanel.add(logoutButton);

        // Action listeners
        checkBalanceButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                showBalanceDetails();
            }
        });

        withdrawButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                showWithdrawScreen();
            }
        });

        depositButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                showDepositScreen();
            }
        });

        historyButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                showTransactionHistory();
            }
        });

        logoutButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                logout();
            }
        });

        // Layout structure
        mainPanel.add(headerPanel, BorderLayout.NORTH);
        mainPanel.add(buttonPanel, BorderLayout.CENTER);
        mainPanel.add(footerPanel, BorderLayout.SOUTH);
        add(mainPanel);
    }

    private JButton createMenuButton(String text) {
        JButton button = new JButton(text);
        button.setFont(new Font("Arial", Font.PLAIN, 14));
        return button;
    }

    private void showBalanceDetails() {
        JDialog dialog = new JDialog(this, "Account Balance", true);
        dialog.setSize(400, 300);
        dialog.setLocationRelativeTo(this);

        JPanel panel = new JPanel(new BorderLayout(10, 10));
        panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));

        JPanel infoPanel = new JPanel(new GridLayout(0, 1, 5, 10));
        infoPanel.add(new JLabel("Account Type: " + currentAccount.getAccountType()));
        infoPanel.add(new JLabel("Current Balance: $" + String.format("%.2f", currentAccount.getBalance())));

        if (currentAccount instanceof SavingsAccount) {
            SavingsAccount sa = (SavingsAccount) currentAccount;
            infoPanel.add(new JLabel("Interest Rate: " + sa.getInterestRate() + "%"));
            infoPanel.add(new JLabel("Estimated Monthly Interest: $" + String.format("%.2f", sa.calculateInterest())));
        } else if (currentAccount instanceof CheckingAccount) {
            CheckingAccount ca = (CheckingAccount) currentAccount;
            infoPanel.add(new JLabel("Overdraft Limit: $" + String.format("%.2f", ca.getOverdraftLimit())));
        }

        JButton closeButton = new JButton("Close");
        closeButton.addActionListener(e -> dialog.dispose());

        panel.add(infoPanel, BorderLayout.CENTER);
        panel.add(closeButton, BorderLayout.SOUTH);

        dialog.add(panel);
        dialog.setVisible(true);
    }

    private void showWithdrawScreen() {
        WithdrawScreen ws = new WithdrawScreen(this, currentAccount, atm);
        ws.setVisible(true);
        updateBalanceLabel();
    }

    private void showDepositScreen() {
        DepositScreen ds = new DepositScreen(this, currentAccount, atm);
        ds.setVisible(true);
        updateBalanceLabel();
    }

    private void showTransactionHistory() {
        TransactionHistoryScreen ts = new TransactionHistoryScreen(this, currentAccount);
        ts.setVisible(true);
    }

    private void logout() {
        LoginScreen login = new LoginScreen();
        login.setVisible(true);
        dispose();
    }

    public void updateBalanceLabel() {
        balanceLabel.setText("Balance: $" + String.format("%.2f", currentAccount.getBalance()));
    }
}