package edu.princeton.toy.choosers;

import java.awt.*;
import java.awt.event.*;

import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;

import edu.princeton.swing.*;
import edu.princeton.swing.text.*;

/**
 * TStyleChooserPane manages a set of styles for various indices and allows the user to change the
 * colors for those indices.
 *
 * @author btsang
 * @version 7.1
 */
public class TStyleChooserPane extends JPanel implements ActionListener, ListSelectionListener
{
    private static final String CLASS_STRING = TStyleChooserPane.class.toString();

    /**
     * The command that causes the TStyleChooserPane to update its components with the internal
     * data.
     */
    public static final String UPDATE_COMMAND = CLASS_STRING + "#updateCommand";

    /**
     * The command that causes the TStyleChooserPane to open a color chooser dialog.
     */
    public static final String CHANGE_COMMAND = CLASS_STRING + "#changeCommand";

    private static final Border BLACK_BORDER = LineBorder.createBlackLineBorder();
    private static final Border ETCHED_BORDER = new EtchedBorder();

    private PList styleList;
    private JLabel previewLabel;
    private JPanel previewPanel;
    private JButton changeButton;
    private JCheckBox boldCheckbox;
    private JCheckBox italicCheckbox;

    private HighlightStyle styles[];
    private Color colors[];
    private boolean bold[];
    private boolean italic[];

    private String styleNames[];

    /**
     * Creates a new TStyleChooserPane.
     */
    public TStyleChooserPane(String styleNames[])
    {
        super(new GridBagLayout());

        int length = styleNames.length;

        this.styleNames = new String[length];
        this.styles = new HighlightStyle[length];
        this.colors = new Color[length];
        this.bold = new boolean[length];
        this.italic = new boolean[length];

        for (int ctr = 0; ctr < length; ctr++)
        {
            this.styleNames[ctr] = styleNames[ctr];
        }

        {   // Prepare the inner panel
            JPanel innerPanel = new JPanel(new GridBagLayout());
            innerPanel.setBorder(ETCHED_BORDER);

            {   // Prepare the style list
                styleList = new PList(this.styleNames);
                styleList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
                styleList.setSelectedIndex(0);
                styleList.addListSelectionListener(this);

                JScrollPane scrollPane = new JScrollPane(
                        styleList,
                        JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
                        JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED
                        );

                Dimension preferredSize = scrollPane.getPreferredSize();
                preferredSize.width = 150;
                scrollPane.setPreferredSize(preferredSize);

                innerPanel.add(
                    scrollPane,
                    new GridBagConstraints(
                        0, 0, 1, 5,
                        0.0, 2.0,
                        GridBagConstraints.NORTHWEST,
                        GridBagConstraints.BOTH,
                        new Insets(2, 2, 2, 2),
                        0, 0
                        )
                    );
            }

            {   // Prepare the preview label
                previewLabel = new JLabel("Current color");

                innerPanel.add(
                    previewLabel,
                    new GridBagConstraints(
                        1, 0, 1, 1,
                        1.0, 0.0,
                        GridBagConstraints.NORTHWEST,
                        GridBagConstraints.NONE,
                        new Insets(2, 2, 2, 2),
                        0, 0
                        )
                    );
            }

            {   // Prepare the preview panel
                previewPanel = new JPanel();

                previewPanel.setPreferredSize(new Dimension(100, 100));
                previewPanel.setBorder(BLACK_BORDER);

                innerPanel.add(
                    previewPanel,
                    new GridBagConstraints(
                        1, 1, 1, 1,
                        1.0, 1.0,
                        GridBagConstraints.SOUTH,
                        GridBagConstraints.NONE,
                        new Insets(2, 2, 2, 2),
                        0, 0
                        )
                    );
            }

            {   // Prepare the change button
                changeButton = new JButton("Change...");
                changeButton.setActionCommand(CHANGE_COMMAND);
                changeButton.addActionListener(this);

                innerPanel.add(
                    changeButton,
                    new GridBagConstraints(
                        1, 2, 1, 1,
                        1.0, 1.0,
                        GridBagConstraints.NORTH,
                        GridBagConstraints.NONE,
                        new Insets(2, 2, 2, 2),
                        0, 0
                        )
                    );
            }

            {   // Prepare the bold checkbox
                boldCheckbox = new JCheckBox("Bold");
                boldCheckbox.setActionCommand(UPDATE_COMMAND);
                boldCheckbox.addActionListener(this);

                innerPanel.add(
                    boldCheckbox,
                    new GridBagConstraints(
                        1, 3, 1, 1,
                        1.0, 0.0,
                        GridBagConstraints.NORTHWEST,
                        GridBagConstraints.NONE,
                        new Insets(2, 2, 2, 2),
                        0, 0
                        )
                    );
            }

            {   // Prepare the italic checkbox
                italicCheckbox = new JCheckBox("Italic");
                italicCheckbox.setActionCommand(UPDATE_COMMAND);
                italicCheckbox.addActionListener(this);

                innerPanel.add(
                    italicCheckbox,
                    new GridBagConstraints(
                        1, 4, 1, 1,
                        1.0, 0.0,
                        GridBagConstraints.NORTHWEST,
                        GridBagConstraints.NONE,
                        new Insets(2, 2, 2, 2),
                        0, 0
                        )
                    );
            }

            add(
                innerPanel,
                new GridBagConstraints(
                    0, 0, 1, 1,
                    1.0, 1.0,
                    GridBagConstraints.CENTER,
                    GridBagConstraints.BOTH,
                    new Insets(50, 25, 50, 25),
                    0, 0
                    )
                );
        }

        doCommand(UPDATE_COMMAND, null);
    }

    /**
     * Gets the style for a given index.
     *
     * @param index The index of the requested style.  An invalid value will result in an
     * ArrayIndexOutOfBoundsException.
     * @return The style for that index.
     */
    public HighlightStyle getStyle(int index)
    {
        if (styles[index] == null)
            styles[index] = new HighlightStyle(colors[index], bold[index], italic[index]);

        return styles[index];
    }

    /**
     * Sets the style for a given index.
     *
     * @param style The new style for the given index.  A null value will result in a
     * NullPointerException.
     * @param index The index of the style we're setting.  An invalid value will result in an
     * ArrayIndexOutOfBoundsException.
     */
    public void setStyle(HighlightStyle style, int index)
    {
        if (style == null)
            throw new NullPointerException();

        styles[index] = style;
        colors[index] = style.getColor();
        bold[index]   = style.isBold();
        italic[index] = style.isItalic();

        if (styleList.getSelectedIndex() == index)
        {
            doCommand(UPDATE_COMMAND, null);
        }
    }

    /**
     * Performs a command based on the argument.
     *
     * @param command A string representing the command.  Note that pointer equality (not string
     * equality) is tested here, so it is important to use the string constants defined in this
     * class.  An IllegalArgumentException will be thrown if the argument is invalid.
     * @return True iff the command was executed sucessfully.
     */
    public synchronized boolean doCommand(String command, Object extraInfo)
    {
        ////////////////////////////////////////////////////////////////////////////////////////////
        if (command == UPDATE_COMMAND)
        {
            int index = styleList.getSelectedIndex();

            if (index == -1)
            {
                index = 0;
                styleList.setSelectedIndex(0);
            }

            previewPanel.setBackground(colors[index]);
            boldCheckbox.getModel().setSelected(bold[index]);
            italicCheckbox.getModel().setSelected(italic[index]);

            return true;
        }
        ////////////////////////////////////////////////////////////////////////////////////////////
        if (command == CHANGE_COMMAND)
        {
            int index = styleList.getSelectedIndex();

            if (index == -1)
            {
                index = 0;
                styleList.setSelectedIndex(0);
            }

            Component comp = this;

            while (comp != null && !(comp instanceof Window))
                comp = comp.getParent();

            Color selection = JColorChooser.showDialog(
                comp,
                "Color selection for " + styleNames[index],
                colors[index]
                );

            if (selection != null && !colors[index].equals(selection))
            {
                colors[index] = selection;
                styles[index] = null;
            }

            doCommand(UPDATE_COMMAND, null);

            return true;
        }

        throw new IllegalArgumentException();
    }

    /**
     * Implement ActionListener to pay attention to changes in the boldCheckbox and
     * changeButton.
     */
    public void actionPerformed(ActionEvent e)
    {
        int index = styleList.getSelectedIndex();

        if (index != -1)
        {
            if (bold[index] != boldCheckbox.getModel().isSelected())
            {
                bold[index] = !bold[index];
                styles[index] = null;
            }

            if (italic[index] != italicCheckbox.getModel().isSelected())
            {
                italic[index] = !italic[index];
                styles[index] = null;
            }
        }

        doCommand(e.getActionCommand(), null);
    }

    /**
     * Implement ListSelectionListener to pay attention to changes in the styleList.
     */
    public void valueChanged(ListSelectionEvent e)
    {
        doCommand(UPDATE_COMMAND, null);
    }
}