package edu.princeton.toy.choosers;

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

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

import edu.princeton.swing.*;

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

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

    /**
     * A list of all font families.  This will later be rearranged so that "Default" is
     * at the top.
     */
    public static final String FONT_FAMILIES[] =
        GraphicsEnvironment.getLocalGraphicsEnvironment().getAvailableFontFamilyNames();

    /**
     * Strings corresponding to the styles available.
     */
    public static final String FONT_STYLES[] =
    {
        "Plain",
        "Bold",
        "Italic",
        "Bold Italic"
    };

    /**
     * Font style masks corresponding to the FONT_STYLES array.
     */
    public static final int FONT_STYLE_MASKS[] =
    {
        Font.PLAIN,
        Font.BOLD,
        Font.ITALIC,
        Font.BOLD | Font.ITALIC
    };

    /**
     * A list of all font sizes.  This is assumed to be in ascending order.
     */
    public static final int FONT_SIZES[] =
    {
         8,  9, 10, 11,
        12, 14, 16, 18,
        20, 22, 24, 26,
        28, 36, 48, 72
    };

    private JComboBox areaComboBox;

    private PList fontList;
    private PList styleList;
    private PList sizeList;

    private JLabel previewLabel;

    private int areaCount;
    private String fontAreas[];

    private int familyIndices[];
    private int styleIndices[];
    private int sizeIndices[];

    private Font fonts[];
    private boolean ignoreUpdate;

    /**
     * Move the default font to the of the FONT_FAMILIES array.
     */
    static
    {
        int index = -1;

        for (int ctr = 0; ctr < FONT_FAMILIES.length && index == -1; ctr++)
        {
            if ("Default".equals(FONT_FAMILIES[ctr]))
                index = ctr;
        }

        if (index != -1)
        {
            for (int ctr = index; ctr > 0; ctr--)
                FONT_FAMILIES[ctr] = FONT_FAMILIES[ctr - 1];

            FONT_FAMILIES[0] = "Default";
        }
    }


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

        int areaCount = fontAreas.length;
        this.fontAreas = new String[areaCount];

        for (int ctr = 0; ctr < areaCount; ctr++)
        {
            if (fontAreas[ctr] == null)
                throw new NullPointerException();

            this.fontAreas[ctr] = fontAreas[ctr];
        }

        this.areaCount = areaCount;

        familyIndices = new int[areaCount];
        styleIndices = new int[areaCount];
        sizeIndices = new int[areaCount];

        fonts = new Font[areaCount];

        ignoreUpdate = false;

        add(
            new JLabel("Area"),
            new GridBagConstraints(
                0, 0, 1, 1,
                0.0, 0.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.VERTICAL,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        {   // Prepare the area combo box
            areaComboBox = new JComboBox(this.fontAreas);
            areaComboBox.addActionListener(this);

            add(
                areaComboBox,
                new GridBagConstraints(
                    1, 0, 3, 1,
                    1.0, 0.0,
                    GridBagConstraints.NORTHWEST,
                    GridBagConstraints.VERTICAL,
                    new Insets(2, 2, 2, 2),
                    0, 0
                    )
                );
        }

        add(
            new JLabel("Font"),
            new GridBagConstraints(
                0, 1, 2, 1,
                2.0, 0.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.VERTICAL,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        add(
            new JLabel("Style"),
            new GridBagConstraints(
                2, 1, 1, 1,
                1.0, 0.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.VERTICAL,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        add(
            new JLabel("Size"),
            new GridBagConstraints(
                3, 1, 1, 1,
                1.0, 0.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.VERTICAL,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        {   // Prepare the font list
            fontList = new PList(FONT_FAMILIES);
            fontList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
            fontList.setSelectedIndex(0);
            fontList.addListSelectionListener(this);

            add(
                new JScrollPane(
                    fontList,
                    JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
                    JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED
                    ),
                new GridBagConstraints(
                    0, 2, 2, 2,
                    2.0, 1.0,
                    GridBagConstraints.NORTHWEST,
                    GridBagConstraints.BOTH,
                    new Insets(2, 2, 2, 2),
                    0, 0
                    )
                );
        }

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

            add(
                new JScrollPane(
                    styleList,
                    JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
                    JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED
                    ),
                new GridBagConstraints(
                    2, 2, 1, 1,
                    1.0, 1.0,
                    GridBagConstraints.NORTHWEST,
                    GridBagConstraints.BOTH,
                    new Insets(2, 2, 2, 2),
                    0, 0
                    )
                );
        }

        {   // Prepare the size list
            Integer objectArray[] = new Integer[FONT_SIZES.length];

            for (int ctr = 0; ctr < objectArray.length; ctr++)
                objectArray[ctr] = new Integer(FONT_SIZES[ctr]);

            sizeList = new PList(objectArray);
            sizeList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
            sizeList.setSelectedIndex(0);
            sizeList.addListSelectionListener(this);

            add(
                new JScrollPane(
                    sizeList,
                    JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
                    JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED
                    ),
                new GridBagConstraints(
                    3, 2, 1, 1,
                    1.0, 1.0,
                    GridBagConstraints.NORTHWEST,
                    GridBagConstraints.BOTH,
                    new Insets(2, 2, 2, 2),
                    0, 0
                    )
                );
        }

        {   // Prepare the preview box
            previewLabel = new JLabel("AaBb YyZz 123", SwingConstants.CENTER);
            previewLabel.setMinimumSize(new Dimension(140, 100));
            previewLabel.setPreferredSize(new Dimension(140, 100));
            previewLabel.setBorder(new EtchedBorder());

            add(
                previewLabel,
                new GridBagConstraints(
                    2, 3, 2, 1,
                    2.0, 0.0,
                    GridBagConstraints.NORTHWEST,
                    GridBagConstraints.BOTH,
                    new Insets(2, 2, 2, 2),
                    0, 0
                    )
                );
        }

        doCommand(UPDATE_COMMAND, null);
    }

    /**
     * Gets the font for a given area.
     *
     * @param areaIndex The index of the area whose font we're getting.  An invalid value will
     * result in an ArrayIndexOutOfBoundsException.
     * @return The font for that area.
     */
    public Font getFont(int areaIndex)
    {
        return fonts[areaIndex];
    }

    /**
     * Sets the font for a given area.
     *
     * @param font The new font for the given area.  A null value will result in a
     * NullPointerException.
     * @param areaIndex The index of the area whose font we're setting.  An invalid value will
     * result in an ArrayIndexOutOfBoundsException.
     */
    public void setFont(Font font, int areaIndex)
    {
        setFont(font.getFamily(), font.isBold(), font.isItalic(), font.getSize(), areaIndex);
    }

    /**
     * Sets the font for a given area.
     *
     * @param family The family of the font.  If null was passed or the family was not found, then
     & &quot;Default&quot; will be used.
     * @param bold Wheter or not the font is bold.
     * @param italic Wheter or not the font is italic.
     * @param size The size of the font.  The font size will be adjusted to the closest available
     * size.
     * @param areaIndex The index of the area whose font we're setting.
     */
    public synchronized void setFont(String family, boolean bold, boolean italic, int size,
                                     int areaIndex)
    {
        if (areaIndex < 0 || areaIndex >= areaCount)
            throw new ArrayIndexOutOfBoundsException();

        // Get the family's index
        int index = -1;
        if (family != null)
        {
            for (int ctr = 0; ctr < FONT_FAMILIES.length && index == -1; ctr++)
            {
                if (FONT_FAMILIES[ctr].equalsIgnoreCase(family))
                    index = ctr;
            }
        }

        if (index == -1)
            familyIndices[areaIndex] = 0;
        else
            familyIndices[areaIndex] = index;

        // Get the style's index
        styleIndices[areaIndex] = (bold?1:0) | (italic?2:0);

        // Get the size's index
        index = 0;
        while (index < FONT_SIZES.length && FONT_SIZES[index] < size)
        {
            index++;
        }

        if (index == FONT_SIZES.length)
        {
            sizeIndices[areaIndex] = FONT_SIZES.length - 1;
        }
        else if (index == 0)
        {
            sizeIndices[areaIndex] = 0;
        }
        else {
            if (FONT_SIZES[index] - size <= size - FONT_SIZES[index - 1])
            {
                sizeIndices[areaIndex] = index;
            }
            else {
                sizeIndices[areaIndex] = index - 1;
            }
        }

        if (areaComboBox.getSelectedIndex() == areaIndex)
        {
            doCommand(UPDATE_COMMAND, null);

            fontList.ensureIndexIsVisible(familyIndices[areaIndex]);
            styleList.ensureIndexIsVisible(styleIndices[areaIndex]);
            sizeList.ensureIndexIsVisible(sizeIndices[areaIndex]);
        }
        else {
            fonts[areaIndex] = new Font(
                FONT_FAMILIES[familyIndices[areaIndex]],
                FONT_STYLE_MASKS[styleIndices[areaIndex]],
                FONT_SIZES[sizeIndices[areaIndex]]
                );
        }
    }

    /**
     * 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)
        {
            ignoreUpdate = true;
            try
            {
                int areaIndex = areaComboBox.getSelectedIndex();

                if (areaIndex == -1)
                {
                    areaIndex = 0;
                    areaComboBox.setSelectedIndex(0);
                }

                fontList.setSelectedIndex(familyIndices[areaIndex]);
                styleList.setSelectedIndex(styleIndices[areaIndex]);
                sizeList.setSelectedIndex(sizeIndices[areaIndex]);

                fonts[areaIndex] = new Font(
                    FONT_FAMILIES[familyIndices[areaIndex]],
                    FONT_STYLE_MASKS[styleIndices[areaIndex]],
                    FONT_SIZES[sizeIndices[areaIndex]]
                    );

                previewLabel.setFont(fonts[areaIndex]);
            }
            finally
            {
                ignoreUpdate = false;
            }
            return true;
        }

        throw new IllegalArgumentException();
    }

    /**
     * Implement ActionListener to pay attention to changes in the areaComboBox.
     */
    public void actionPerformed(ActionEvent e)
    {
        if (ignoreUpdate)
            return;

        int areaIndex = areaComboBox.getSelectedIndex();
        doCommand(UPDATE_COMMAND, null);

        if (areaIndex != -1)
        {
            fontList.ensureIndexIsVisible(familyIndices[areaIndex]);
            styleList.ensureIndexIsVisible(styleIndices[areaIndex]);
            sizeList.ensureIndexIsVisible(sizeIndices[areaIndex]);
        }
    }

    /**
     * Implement ListSelectionListener to pay attention to changes in the fontList, styleList, and
     * sizeList.
     */
    public void valueChanged(ListSelectionEvent e)
    {
        if (ignoreUpdate)
            return;

        int areaIndex = areaComboBox.getSelectedIndex();

        if (areaIndex != -1)
        {
            int index = fontList.getSelectedIndex();
            if (index != -1)
                familyIndices[areaIndex] = index;

            index = styleList.getSelectedIndex();
            if (index != -1)
                styleIndices[areaIndex] = index;

            index = sizeList.getSelectedIndex();
            if (index != -1)
                sizeIndices[areaIndex] = index;
        }

        doCommand(UPDATE_COMMAND, null);
    }
}