import java.awt.*;      
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
import java.util.*;
import javax.swing.border.*;

/**
 * Class representing the Order UI dialog. 
 * Responsible for collecting user input, 
 * creating Order and Pizza objects, and 
 * updating the order queue.
 */
public class OrderUI extends JFrame {
    private final OrderQueue _queue;  // The central queue of active orders
    private final OrderPrinter _printer; // Printer to print pizza labels on

    //--> These fields and buttons need to be referenced throughout
    //--> the lifetime of the OrderUI, so they're created at
    //--> construction time and kept track of with reference fields.
    private final JTextField _sizeField = new JTextField(2);
    private final JTextField _toppingsField = new JTextField(12);
    private final JTextField _nameField = new JTextField(30);
    private final JTextField _addressField = new JTextField(45);
    private final JTextField _phoneField = new JTextField(14);
    private final JLabel _statusField = new JLabel(" ");
    private final JButton _addButton = new JButton("Add");
    private final JButton _cancelButton = new JButton("Cancel");
    private final JButton _doneButton = new JButton("Done");

    //--> The _order represents the current (partially complete)
    //--> order; it starts out empty and returns to that state
    //--> after each order is put onto the queue.
    private Order _order = new Order();

    /** Constructor; creates UI given an OrderQueue to place orders
        and an OrderPrinter to print orders. */
    public OrderUI(OrderQueue queue, OrderPrinter printer) {
        //--> Superclass JFrame constructor sets text of title bar from argument:
        super("APDTS - Order");

        // Keep track of queue and printer:
        _queue = queue;
        _printer = printer;

        setupLayout();

        _addButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                addPizzaToOrder();
            }
        });

        _cancelButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                resetUI();
            }
        });

        _doneButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                recordOrder();
            }
        });

        // Shut down system when user closes window.
        this.addWindowListener(new WindowAdapter() {
                public void windowClosing(WindowEvent e) {
                    System.out.println("Shutting down APDTS.");
                    System.exit(0);
                }
            }
        );
    }

    // Reset UI back to initial state
    private void resetUI() {
        _sizeField.setText("");
        _toppingsField.setText("");
        _nameField.setText("");
        _addressField.setText("");
        _phoneField.setText("");
        _order = new Order();            
        updateUI();
    }

    // Record order w/current customer info, putting information on the queue.
    private void recordOrder() {
        // If there's information in the pizza fields, assume
        // it's supposed to go into the order:
        if (!_sizeField.getText().equals("")) 
            addPizzaToOrder();

        /* Suggested interface:

        // Copy customer information to Order:
        _order.setCustomer(_nameField.getText(),
                           _addressField.getText(),
                           _phoneField.getText());

        // Move the order onto the central queue:
        _queue.add(_order);
        */

        printOrder();

        resetUI();
    }

    // Print current order's pizzas onto label printer
    private void printOrder() {
        /* Suggested interface: 
        Iterator i = _order.pizzaIterator();
        while (i.hasNext()) {
            Pizza p = (Pizza)i.next();
            _printer.printLabel(_order,p);
        }
        */
    }

    // Add the current pizza (specified in UI fields) to the order.
    private void addPizzaToOrder() {
        /* Suggested interface: 
        Pizza p = new Pizza(_sizeField.getText(),_toppingsField.getText());
        _order.add(p);
        */
        _sizeField.setText("");
        _toppingsField.setText("");
        updateUI();
    }

    // Updates all parts of the UI that depend on the current incomplete
    // order
    private void updateUI() {
        /* Suggested interface:
        int numPizzas = _order.getNumPizzas();
        double totalPrice = _order.getTotalPrice();
        _statusField.setText(""+numPizzas+" pizzas, total: $"+totalPrice);
        */
    }

    // Create a combination label/edit field component made out of
    // a panel + subcomponents:
    private JComponent makeLabelledField(String label, JTextComponent field) {
        JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT));
        JLabel l = new JLabel(label);
        panel.add(l);
        panel.add(field);
        panel.add(Box.createHorizontalGlue());
        panel.setAlignmentX(Component.LEFT_ALIGNMENT);
        return panel;
    }

    // Set up UI layout for all the AWT/Swing components.
    private void setupLayout() {
        Border paneEdge = BorderFactory.createEmptyBorder(5,5,5,5);

        getContentPane().setLayout(new BoxLayout(getContentPane(),BoxLayout.Y_AXIS));
        JPanel orderPane = new JPanel();
        orderPane.setLayout(new BoxLayout(orderPane,BoxLayout.Y_AXIS));
        orderPane.setBorder(paneEdge);
        getContentPane().add(orderPane);

        JPanel customerPane = new JPanel();
        customerPane.setLayout(new BoxLayout(customerPane,BoxLayout.Y_AXIS));
        customerPane.setBorder(paneEdge);
        getContentPane().add(customerPane);

        _statusField.setBorder(paneEdge);
        getContentPane().add(_statusField);  

        //---Set up orderPane---

        orderPane.add(new JLabel("Enter Order"));
        orderPane.add(makeLabelledField("Size",_sizeField));
        orderPane.add(makeLabelledField("Toppings",_toppingsField));
        JPanel buttonPanel1 = new JPanel(new FlowLayout(FlowLayout.RIGHT));
        buttonPanel1.setAlignmentX(Component.LEFT_ALIGNMENT);
        orderPane.add(buttonPanel1);
        buttonPanel1.add(_addButton);

        //---Set up customerPane---

        customerPane.add(makeLabelledField("Name",_nameField));
        customerPane.add(makeLabelledField("Address",_addressField));
        customerPane.add(makeLabelledField("Phone",_phoneField));
        JPanel buttonPanel2 = new JPanel(new FlowLayout(FlowLayout.RIGHT));
        buttonPanel2.setAlignmentX(Component.LEFT_ALIGNMENT);
        customerPane.add(buttonPanel2);
        buttonPanel2.add(_cancelButton);
        buttonPanel2.add(_doneButton);

        pack();
    }

    // Unit test
    public static void main(String[] args) {
        new OrderUI(new OrderQueue(), new OrderPrinter()).show();
    }
};