/* copyright

This file is part of JKomasto2.
Written in 2022 by Usawashi <usawashi16@yahoo.co.jp>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.

copyright */

import javax.swing.AbstractButton;
import javax.swing.DefaultButtonModel;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import java.awt.Image;
import java.awt.Graphics;
import java.awt.Dimension;
import java.awt.Shape;
import java.awt.Rectangle;
import java.awt.Component;
import java.awt.image.BufferedImage;
import java.awt.geom.Ellipse2D;
import java.awt.event.MouseListener;
import java.awt.event.MouseEvent;
import java.awt.event.KeyListener;
import java.awt.event.KeyEvent;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.FocusListener;
import java.awt.event.FocusEvent;
import java.net.URL;

import javax.swing.JFrame;

class
TwoToggleButton extends AbstractButton
implements KeyListener, MouseListener, FocusListener {

    private String
    primaryName,
    secondaryName;

//   -  -%-  -

    private boolean
    primaryToggled = false,
    secondaryToggled = false;

    private Image
    primaryToggledIcon,
    secondaryToggledIcon,
    primaryUntoggledIcon,
    secondaryUntoggledIcon;

    private int
    nextEventID = ActionEvent.ACTION_FIRST;

//   -  -%-  -

    private static Image
    button,
    selectedOverlay,
    disabledOverlay;

//  ---%-@-%---

    public void
    togglePrimary()
    {
        setPrimaryToggled(!primaryToggled);
    }

    public void
    toggleSecondary()
    {
        setSecondaryToggled(!secondaryToggled);
    }

    public void
    setPrimaryToggled(boolean toggled)
    {
        primaryToggled = toggled;
        repaint();
        announce(primaryName, toggled);
    }

    public void
    setSecondaryToggled(boolean toggled)
    {
        secondaryToggled = toggled;
        repaint();
        announce(secondaryName, toggled);
    }

    public boolean
    getPrimaryToggled()
    {
        return primaryToggled;
    }

    public boolean
    getSecondaryToggled()
    {
        return secondaryToggled;
    }

//   -  -%-  -

    private void
    announce(String name, boolean toggled)
    {
        ActionEvent eA = new ActionEvent(
            this, nextEventID++,
            name + (toggled ? "On" : "Off")
        );
        for (ActionListener listener: getActionListeners())
            listener.actionPerformed(eA);
    }


    protected void
    paintComponent(Graphics g)
    {
        g.drawImage(button, 0, 0, this);
        if (!isEnabled())
            g.drawImage(disabledOverlay, 0, 0, this);
        if (isFocusOwner())
            g.drawImage(selectedOverlay, 0, 0, this);

        if (secondaryToggled)
            g.drawImage(secondaryToggledIcon, 0, 0, this);
        else
            g.drawImage(secondaryUntoggledIcon, 0, 0, this);
        if (primaryToggled)
            g.drawImage(primaryToggledIcon, 0, 0, this);
        else
            g.drawImage(primaryUntoggledIcon, 0, 0, this);
    }


    public void
    mousePressed(MouseEvent eM)
    {
        boolean shift = eM.isShiftDown();
        boolean prim = eM.getButton() == MouseEvent.BUTTON1;
        boolean secon = eM.getButton() == MouseEvent.BUTTON3;
        secon |= shift && prim;

        if (secon) toggleSecondary();
        else if (prim) togglePrimary();

        requestFocusInWindow();
    }

    public void
    keyPressed(KeyEvent eK)
    {
        boolean shift = eK.isShiftDown();
        boolean prim = eK.getKeyCode() == KeyEvent.VK_SPACE;
        boolean secon = eK.getKeyCode() == KeyEvent.VK_ENTER;
        secon |= shift && prim;

        if (secon) toggleSecondary();
        else if (prim) togglePrimary();

        requestFocusInWindow();
    }

    public void
    focusGained(FocusEvent eF) { repaint(); }

    public void
    focusLost(FocusEvent eF) { repaint(); }


    public void
    mouseClicked(MouseEvent eM) { }

    public void
    mouseReleased(MouseEvent eM) { }

    public void
    mouseEntered(MouseEvent eM) { }

    public void
    mouseExited(MouseEvent eM) { }

    public void
    keyReleased(KeyEvent eK) { }

    public void
    keyTyped(KeyEvent eK) { }

    // (悪) If we don't have the 'armed' behaviour of JButton,
    // we really need to rectify that, it's important for this
    // use case.

//  ---%-@-%---

    TwoToggleButton(String primaryName, String secondaryName)
    {
        if (button == null) loadCommonImages();
        this.primaryName = primaryName;
        this.secondaryName = secondaryName;

        setModel(new DefaultButtonModel());
        setFocusable(true);
        setOpaque(false);

        int w = button.getWidth(null);
        int h = button.getHeight(null);
        setPreferredSize(new Dimension(w, h));
        loadSpecificImages();

        this.addKeyListener(this);
        this.addMouseListener(this);
        this.addFocusListener(this);
    }

    private void
    loadSpecificImages()
    {
        String p1 = "graphics/" + primaryName + "Toggled.png";
        String p2 = "graphics/" + secondaryName + "Toggled.png";
        String p3 = "graphics/" + primaryName + "Untoggled.png";
        String p4 = "graphics/" + secondaryName + "Untoggled.png";
        URL u1 = getClass().getResource(p1);
        URL u2 = getClass().getResource(p2);
        URL u3 = getClass().getResource(p3);
        URL u4 = getClass().getResource(p4);
        if (u1 == null) primaryToggledIcon = null;
        else primaryToggledIcon = new ImageIcon(u1).getImage();
        if (u2 == null) secondaryToggledIcon = null;
        else secondaryToggledIcon = new ImageIcon(u2).getImage();
        if (u3 == null) primaryUntoggledIcon = null;
        else primaryUntoggledIcon = new ImageIcon(u3).getImage();
        if (u4 == null) secondaryUntoggledIcon = null;
        else secondaryUntoggledIcon = new ImageIcon(u4).getImage();
    }

//   -  -%-  -

    private static void
    loadCommonImages()
    {
        Class c = TwoToggleButton.class;
        URL u1 = c.getResource("graphics/button.png");
        URL u2 = c.getResource("graphics/disabledOverlay.png");
        URL u3 = c.getResource("graphics/selectedOverlay.png");
        assert u1 != null && u2 != null && u3 != null;
        button = new ImageIcon(u1).getImage();
        disabledOverlay = new ImageIcon(u2).getImage();
        selectedOverlay = new ImageIcon(u3).getImage();
    }

}


class
RoundButton extends AbstractButton
implements KeyListener, MouseListener, FocusListener {

    private Image
    image;

//     -    -%-     -

    private Image
    copy,
    scaled;

    private int
    nextEventID = ActionEvent.ACTION_FIRST;

//   -  -%-  -

    private static Image
    button,
    selectedOverlay,
    disabledOverlay;

    private static Shape
    roundClip;

//  ---%-@-%---

    public void
    setImage(Image n)
    {
        image = n;
        copy = null;
        scaled = null;

        if (image != null)
        {
            image.flush();
            prepareImage(image, this);
        }
    }

//     -    -%-     -

    public boolean
    imageUpdate(Image img, int f, int x, int y, int w, int h)
    {
         // AbstractButton overrode this to refuse updates for
        // images that aren't the button's icon. We don't use
        // the icon, so we're overriding it back. Also, we have
        // some async work to do regarding the images.

        if ((f & (ABORT|ERROR)) != 0) return false;

        boolean all = (f & ALLBITS) != 0;
        boolean frame = (f & FRAMEBITS) != 0;
        boolean some = (f & SOMEBITS) != 0;

        if (frame && img != this.image) return false;

        if (img == this.image && (all || frame))
        {
            int ow = img.getWidth(null);
            int oh = img.getHeight(null);

            if (copy == null)
            {
                int type = BufferedImage.TYPE_INT_ARGB;
                copy = new BufferedImage(ow, oh, type);
            }

            Graphics g = copy.getGraphics();
            g.drawImage(img, 0, 0, null);
            g.dispose();

            int algo = Image.SCALE_SMOOTH;
            Rectangle b = roundClip.getBounds();
            int sw = ow > oh ? -1 : b.width;
            int sh = oh > ow ? -1 : b.height;
            scaled = copy.getScaledInstance(sw, sh, algo);
            /*
            * We create a scaled instance from a BufferedImage copy
            * rather than this.image directly, to avoid a ClassCast
            * Exception bug in the JDK, where ColorModel was
            * incorrectly casting an int array of input data into
            * a byte array. I'm not sure why that bug exists nor
            * why they haven't noticed it, but.
            */
            repaint();
        }
        if (img == scaled && (some || all))
        {
            repaint();
        }
        return all ? false : true;
    }

    protected void
    paintComponent(Graphics g)
    {
        g.drawImage(button, 0, 0, this);
        if (!isEnabled())
            g.drawImage(disabledOverlay, 0, 0, this);
        if (isFocusOwner())
            g.drawImage(selectedOverlay, 0, 0, this);

        if (scaled == null) return;

        Rectangle b = roundClip.getBounds();
        Shape defaultClip = g.getClip();
        g.setClip(roundClip);
        g.drawImage(scaled, b.x, b.y, this);
        getParent().repaint();
        // I don't know why, but when we repaint ourselves, our
        // parent doesn't repaint, so nothing seems to happen.
        g.setClip(defaultClip);
    }

    private void
    announce()
    {
        ActionEvent eA = new ActionEvent(this, nextEventID++, null);
        for (ActionListener listener: getActionListeners())
            listener.actionPerformed(eA);
    }


    public void
    keyPressed(KeyEvent eK)
    {
        if (eK.getKeyCode() != KeyEvent.VK_SPACE) return;
        doClick();
    }

    public void
    mouseClicked(MouseEvent eM) { announce(); }

    public void
    focusGained(FocusEvent eF) { repaint(); }

    public void
    focusLost(FocusEvent eF) { repaint(); }


    public void
    mousePressed(MouseEvent eM) { }

    public void
    mouseReleased(MouseEvent eM) { }

    public void
    mouseEntered(MouseEvent eM) { }

    public void
    mouseExited(MouseEvent eM) { }

    public void
    keyReleased(KeyEvent eK) { }

    public void
    keyTyped(KeyEvent eK) { }

    // (悪) Again, armed?

//  ---%-@-%---

    RoundButton()
    {
        if (button == null) loadCommonImages();

        setModel(new DefaultButtonModel());
        setFocusable(true);
        setOpaque(false);

        int w = button.getWidth(null);
        int h = button.getHeight(null);
        setPreferredSize(new Dimension(w, h));

        this.addKeyListener(this);
        this.addMouseListener(this);
        this.addFocusListener(this);
    }

//   -  -%-  -

    private static void
    loadCommonImages()
    {
        Class c = TwoToggleButton.class;
        URL u1 = c.getResource("graphics/button.png");
        URL u2 = c.getResource("graphics/disabledOverlay.png");
        URL u3 = c.getResource("graphics/selectedOverlay.png");
        assert u1 != null && u2 != null && u3 != null;
        button = new ImageIcon(u1).getImage();
        disabledOverlay = new ImageIcon(u2).getImage();
        selectedOverlay = new ImageIcon(u3).getImage();

        int radius = 6;
        roundClip = new Ellipse2D.Float(
            radius,
            radius,
            button.getWidth(null) - (2 * radius),
            button.getHeight(null) - (2 * radius)
        );
    }

}


class
TwoToggleButtonTest {

    public static void
    main(String... args)
    {
        if (args.length != 2)
        {
            String err = "Please give two toggle names.";
            System.err.println(err);
            System.exit(1);
        }

        String p = args[0], s = args[1];
        TwoToggleButton t1 = new TwoToggleButton(p, s);
        TwoToggleButton t2 = new TwoToggleButton(p, s);
        TwoToggleButton t3 = new TwoToggleButton(p, s);

        JFrame mainframe = new JFrame("Two-toggle button test");
        mainframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        mainframe.setLocationByPlatform(true);
        mainframe.add(t1, java.awt.BorderLayout.WEST);
        mainframe.add(t2);
        mainframe.add(t3, java.awt.BorderLayout.EAST);
        mainframe.pack();
        t2.setEnabled(false);
        t3.requestFocusInWindow();
        mainframe.setVisible(true);
    }

}