/*
 * @(#)SynthScrollPaneUI.java	1.12 03/12/19
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.swing.plaf.synth;

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

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeEvent;

import java.awt.*;
import java.awt.event.*;
import sun.swing.plaf.synth.SynthUI;


/**
 * Synth's ScrollPaneUI.
 *
 * @version 1.12, 12/19/03
 * @author Scott Violet
 */
class SynthScrollPaneUI extends BasicScrollPaneUI implements
                 PropertyChangeListener, SynthUI {
    private SynthStyle style;

    public static ComponentUI createUI(JComponent x) {
	return new SynthScrollPaneUI();
    }

    public void update(Graphics g, JComponent c) {
        SynthContext context = getContext(c);

        SynthLookAndFeel.update(context, g);
        context.getPainter().paintScrollPaneBackground(context,
                          g, 0, 0, c.getWidth(), c.getHeight());
        paint(context, g);
        context.dispose();
    }

    public void paint(Graphics g, JComponent c) {
        SynthContext context = getContext(c);

        paint(context, g);
        context.dispose();
    }

    protected void paint(SynthContext context, Graphics g) {
	Border vpBorder = scrollpane.getViewportBorder();
	if (vpBorder != null) {
	    Rectangle r = scrollpane.getViewportBorderBounds();
	    vpBorder.paintBorder(scrollpane, g, r.x, r.y, r.width, r.height);
	}
    }


    public void paintBorder(SynthContext context, Graphics g, int x,
                            int y, int w, int h) {
        context.getPainter().paintScrollPaneBorder(context, g, x, y, w, h);
    }

    protected void installDefaults(JScrollPane scrollpane) {
        updateStyle(scrollpane);
    }

    private void updateStyle(JScrollPane c) {
        SynthContext context = getContext(c, ENABLED);
        SynthStyle oldStyle = style;

        style = SynthLookAndFeel.updateStyle(context, this);
        if (style != oldStyle) {
            Border vpBorder = scrollpane.getViewportBorder();
            if ((vpBorder == null) ||( vpBorder instanceof UIResource)) {
                scrollpane.setViewportBorder(new ViewportBorder(context));
            }
            if (oldStyle != null) {
                uninstallKeyboardActions(c);
                installKeyboardActions(c);
            }
        }
        context.dispose();
    }


    protected void installListeners(JScrollPane c) {
        super.installListeners(c);
        c.addPropertyChangeListener(this);
    }

    protected void uninstallDefaults(JScrollPane c) {
        SynthContext context = getContext(c, ENABLED);

        style.uninstallDefaults(context);
        context.dispose();

        if (scrollpane.getViewportBorder() instanceof UIResource) {
            scrollpane.setViewportBorder(null);
        }
    }


    protected void uninstallListeners(JComponent c) {
        super.uninstallListeners(c);
        c.removePropertyChangeListener(this);
    }


    public SynthContext getContext(JComponent c) {
        return getContext(c, getComponentState(c));
    }

    private SynthContext getContext(JComponent c, int state) {
        return SynthContext.getContext(SynthContext.class, c,
                    SynthLookAndFeel.getRegion(c), style, state);
    }


    private Region getRegion(JComponent c) {
        return SynthLookAndFeel.getRegion(c);
    }


    private int getComponentState(JComponent c) {
        return SynthLookAndFeel.getComponentState(c);
    }

    public void propertyChange(PropertyChangeEvent e) {
        if (SynthLookAndFeel.shouldUpdateStyle(e)) {
            updateStyle(scrollpane);
        }
    }



    private class ViewportBorder extends AbstractBorder implements UIResource {
        private Insets insets;

        ViewportBorder(SynthContext context) {
            this.insets = (Insets)context.getStyle().get(context,
                                            "ScrollPane.viewportBorderInsets");
            if (this.insets == null) {
                this.insets = SynthLookAndFeel.EMPTY_UIRESOURCE_INSETS;
            }
        }

        public void paintBorder(Component c, Graphics g, int x, int y,
                            int width, int height) {
            JComponent jc = (JComponent)c;
            SynthContext context = getContext(jc);
            SynthStyle style = context.getStyle();
            if (style == null) {
                assert false: "SynthBorder is being used outside after the " +
                              " UI has been uninstalled";
                return;
            }
            context.getPainter().paintViewportBorder(context, g, x, y, width,
                                                     height);
            context.dispose();
        }

        public Insets getBorderInsets(Component c) { 
            return getBorderInsets(c, null);
        }

        public Insets getBorderInsets(Component c, Insets insets) {
            if (insets == null) {
                return new Insets(this.insets.top, this.insets.left,
                                  this.insets.bottom, this.insets.right);
            }
            insets.top = this.insets.top;
            insets.bottom = this.insets.bottom;
            insets.left = this.insets.left;
            insets.right = this.insets.left;
            return insets;
        }

        public boolean isBorderOpaque() {
            return false;
        }
    }
}