/*

 * Copyright 2003-2008 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package sun.awt.X11;

import java.awt.*;

import java.awt.event.*;

import java.awt.image.BufferedImage;

import sun.awt.SunToolkit;

import sun.awt.X11GraphicsConfig;

/**

* A simple vertical scroll bar.

*/

abstract class XScrollbar {

    /**

     * The thread that asynchronously tells the scrollbar to scroll.

     * @see #startScrolling

     */

    private static XScrollRepeater scroller = new XScrollRepeater(null);

    /*

     * The repeater that used for concurrent scrolling of the vertical and horizontal scrollbar

     * And so there is not static keyword

     * See 6243382 for more information

     */

    private XScrollRepeater i_scroller = new XScrollRepeater(null);

    // Thumb length is always >= MIN_THUMB_H

    private final static int MIN_THUMB_H = 5;

    private static final int ARROW_IND = 1;

    XScrollbarClient sb;

    //Use set methods to set scrollbar parameters

    private int val;

    private int min;

    private int max;

    private int vis;

    private int line;

    private int page;

    private boolean needsRepaint = true;

    private boolean pressed = false;

    private boolean dragging = false;

    Polygon firstArrow, secondArrow;

    int width, height; // Dimensions of the visible part of the parent window

    int barWidth, barLength; // Rotation-independent values,

                             // equal to (width, height) for vertical,

                             // rotated by 90 for horizontal.

                             // That is, barLength is always the length between

                             // the tips of the arrows.

    int arrowArea;     // The area reserved for the scroll arrows

    int alignment;

    public static final int ALIGNMENT_VERTICAL = 1, ALIGNMENT_HORIZONTAL = 2;

    int mode;

    Point thumbOffset;

    private Rectangle prevThumb;

    public XScrollbar(int alignment, XScrollbarClient sb) {

        this.sb = sb;

        this.alignment = alignment;

    }

    public boolean needsRepaint() {

        return needsRepaint;

    }

    void notifyValue(int v) {

        notifyValue(v, false);

    }

    void notifyValue(int v, final boolean isAdjusting) {

        if (v < min) {

            v = min;

        } else if (v > max - vis) {

            v = max - vis;

        }

        final int value = v;

        final int mode = this.mode;

        if ((sb != null) && ((value != val)||(!pressed))) {

            SunToolkit.executeOnEventHandlerThread(sb.getEventSource(), new Runnable() {

                    public void run() {

                        sb.notifyValue(XScrollbar.this, mode, value, isAdjusting);

                    }

                });

        }

    }

    abstract protected void rebuildArrows();

    public void setSize(int width, int height) {

        this.width = width;

        this.height = height;

    }

    /**

     * Creates oriented directed arrow

     */

    protected Polygon createArrowShape(boolean vertical, boolean up) {

        Polygon arrow = new Polygon();

        // TODO: this should be done polymorphically in subclasses

        // FIXME: arrows overlap the thumb for very wide scrollbars

        if (vertical) {

            int x = width / 2 - getArrowWidth()/2;

            int y1 = (up ? ARROW_IND : barLength - ARROW_IND);

            int y2 = (up ? getArrowWidth() : barLength - getArrowWidth() - ARROW_IND);

            arrow.addPoint(x + getArrowWidth()/2, y1);

            arrow.addPoint(x + getArrowWidth(), y2);

            arrow.addPoint(x, y2);

            arrow.addPoint(x + getArrowWidth()/2, y1);

        } else {

            int y = height / 2 - getArrowWidth()/2;

            int x1 = (up ? ARROW_IND : barLength - ARROW_IND);

            int x2 = (up ? getArrowWidth() : barLength - getArrowWidth() - ARROW_IND);

            arrow.addPoint(x1, y + getArrowWidth()/2);

            arrow.addPoint(x2, y + getArrowWidth());

            arrow.addPoint(x2, y);

            arrow.addPoint(x1, y + getArrowWidth()/2);

        }

        return arrow;

    }

    /**

     * Gets the area of the scroll track

     */

    protected abstract Rectangle getThumbArea();

    /**

     * paint the scrollbar

     * @param g the graphics context to paint into

     * @param colors the colors to use when painting the scrollbar

     * @param width the width of the scrollbar

     * @param height the height of the scrollbar

     * @param paintAll paint the whole scrollbar if true, just the thumb is false

     */

    void paint(Graphics g, Color colors[], boolean paintAll) {

        boolean useBufferedImage = false;

        Graphics2D g2 = null;

        BufferedImage buffer = null;

        if (!(g instanceof Graphics2D)) {

            // Fix for 5045936, 5055171. While printing, g is an instance

            //   of sun.print.ProxyPrintGraphics which extends Graphics.

            //   So we use a separate buffered image and its graphics is

            //   always Graphics2D instance

            X11GraphicsConfig graphicsConfig = (X11GraphicsConfig)(sb.getEventSource().getGraphicsConfiguration());

            buffer = graphicsConfig.createCompatibleImage(width, height);

            g2 = buffer.createGraphics();

            useBufferedImage = true;

        } else {

            g2 = (Graphics2D)g;

        }

        try {

            Rectangle thumbRect = calculateThumbRect();

//              if (prevH == thumbH && prevY == thumbPosY) {

//                  return;

//              }

            prevThumb = thumbRect;

            // TODO: Share Motif colors

            Color back = colors[XComponentPeer.BACKGROUND_COLOR];

            Color selectColor = new Color(MotifColorUtilities.calculateSelectFromBackground(back.getRed(),back.getGreen(),back.getBlue()));

            Color darkShadow = new Color(MotifColorUtilities.calculateBottomShadowFromBackground(back.getRed(),back.getGreen(),back.getBlue()));

            Color lightShadow = new Color(MotifColorUtilities.calculateTopShadowFromBackground(back.getRed(),back.getGreen(),back.getBlue()));

            XToolkit.awtLock();

            try {

                XlibWrapper.XFlush(XToolkit.getDisplay());

            } finally {

                XToolkit.awtUnlock();

            }

            /* paint the background slightly darker */

            if (paintAll) {

                // fill the entire background

                g2.setColor(selectColor);

                if (alignment == ALIGNMENT_HORIZONTAL) {

                    g2.fillRect(0, 0, thumbRect.x, height);

                    g2.fillRect(thumbRect.x + thumbRect.width , 0, width - (thumbRect.x + thumbRect.width), height);

                } else {

                    g2.fillRect(0, 0, width, thumbRect.y);

                    g2.fillRect(0, thumbRect.y + thumbRect.height, width, height - (thumbRect.y + thumbRect.height));

                }

                // Paint edges

                // TODO: Share Motif 3d rect drawing

                g2.setColor(darkShadow);

                g2.drawLine(0, 0, width-1, 0);           // top

                g2.drawLine(0, 0, 0, height-1);          // left

                g2.setColor(lightShadow);

                g2.drawLine(1, height-1, width-1, height-1); // bottom

                g2.drawLine(width-1, 1, width-1, height-1);  // right

            } else {

                // Clear all thumb area

                g2.setColor(selectColor);

                Rectangle thumbArea = getThumbArea();

                g2.fill(thumbArea);

            }

            if (paintAll) {

                // ************ paint the arrows

                 paintArrows(g2, colors[XComponentPeer.BACKGROUND_COLOR], darkShadow, lightShadow );

            }

            // Thumb

            g2.setColor(colors[XComponentPeer.BACKGROUND_COLOR]);

            g2.fillRect(thumbRect.x, thumbRect.y, thumbRect.width, thumbRect.height);

            g2.setColor(lightShadow);

            g2.drawLine(thumbRect.x, thumbRect.y,

                       thumbRect.x + thumbRect.width, thumbRect.y); // top

            g2.drawLine(thumbRect.x, thumbRect.y,

                       thumbRect.x, thumbRect.y+thumbRect.height); // left

            g2.setColor(darkShadow);

            g2.drawLine(thumbRect.x+1,

                       thumbRect.y+thumbRect.height,

                       thumbRect.x+thumbRect.width,

                       thumbRect.y+thumbRect.height);  // bottom

            g2.drawLine(thumbRect.x+thumbRect.width,

                       thumbRect.y+1,

                       thumbRect.x+thumbRect.width,

                       thumbRect.y+thumbRect.height); // right

        } finally {

            if (useBufferedImage) {

                g2.dispose();

            }

        }

        if (useBufferedImage) {

            g.drawImage(buffer, 0, 0, null);

        }

        XToolkit.awtLock();

        try {

            XlibWrapper.XFlush(XToolkit.getDisplay());

        } finally {

            XToolkit.awtUnlock();

        }

    }

      void paintArrows(Graphics2D g, Color background, Color darkShadow, Color lightShadow) {

          g.setColor(background);

        // paint firstArrow

        if (pressed && (mode == AdjustmentEvent.UNIT_DECREMENT)) {

            g.fill(firstArrow);

            g.setColor(lightShadow);

            g.drawLine(firstArrow.xpoints[0],firstArrow.ypoints[0],

                    firstArrow.xpoints[1],firstArrow.ypoints[1]);

            g.drawLine(firstArrow.xpoints[1],firstArrow.ypoints[1],

                    firstArrow.xpoints[2],firstArrow.ypoints[2]);

            g.setColor(darkShadow);

            g.drawLine(firstArrow.xpoints[2],firstArrow.ypoints[2],

                    firstArrow.xpoints[0],firstArrow.ypoints[0]);

        }

        else {

            g.fill(firstArrow);

            g.setColor(darkShadow);

            g.drawLine(firstArrow.xpoints[0],firstArrow.ypoints[0],

                    firstArrow.xpoints[1],firstArrow.ypoints[1]);

            g.drawLine(firstArrow.xpoints[1],firstArrow.ypoints[1],

                    firstArrow.xpoints[2],firstArrow.ypoints[2]);

            g.setColor(lightShadow);

            g.drawLine(firstArrow.xpoints[2],firstArrow.ypoints[2],

                    firstArrow.xpoints[0],firstArrow.ypoints[0]);

        }

        g.setColor(background);

        // paint second Arrow

        if (pressed && (mode == AdjustmentEvent.UNIT_INCREMENT)) {

            g.fill(secondArrow);

            g.setColor(lightShadow);

            g.drawLine(secondArrow.xpoints[0],secondArrow.ypoints[0],

                    secondArrow.xpoints[1],secondArrow.ypoints[1]);

            g.setColor(darkShadow);

            g.drawLine(secondArrow.xpoints[1],secondArrow.ypoints[1],

                    secondArrow.xpoints[2],secondArrow.ypoints[2]);

            g.drawLine(secondArrow.xpoints[2],secondArrow.ypoints[2],

                    secondArrow.xpoints[0],secondArrow.ypoints[0]);

        }

        else {

            g.fill(secondArrow);

            g.setColor(darkShadow);

            g.drawLine(secondArrow.xpoints[0],secondArrow.ypoints[0],

                    secondArrow.xpoints[1],secondArrow.ypoints[1]);

            g.setColor(lightShadow);

            g.drawLine(secondArrow.xpoints[1],secondArrow.ypoints[1],

                    secondArrow.xpoints[2],secondArrow.ypoints[2]);

            g.drawLine(secondArrow.xpoints[2],secondArrow.ypoints[2],

                    secondArrow.xpoints[0],secondArrow.ypoints[0]);

        }

    }

    /**

     * Tell the scroller to start scrolling.

     */

    void startScrolling() {

        log.finer("Start scrolling on " + this);

        // Make sure that we scroll at least once

        scroll();

        // wake up the scroll repeater

        if (scroller == null) {

            // If there isn't a scroller, then create

            // one and start it.

            scroller = new XScrollRepeater(this);

        } else {

            scroller.setScrollbar(this);

        }

        scroller.start();

    }

    /**

     * Tell the instance scroller to start scrolling.

     * See 6243382 for more information

     */

    void startScrollingInstance() {

        log.finer("Start scrolling on " + this);

        // Make sure that we scroll at least once

        scroll();

        i_scroller.setScrollbar(this);

        i_scroller.start();

    }

    /**

     * Tell the instance scroller to stop scrolling.

     * See 6243382 for more information

     */

    void stopScrollingInstance() {

        log.finer("Stop scrolling on " + this);

        i_scroller.stop();

    }

    /**

     * The set method for mode property.

     * See 6243382 for more information

     */

    public void setMode(int mode){

        this.mode = mode;

    }

    /**

     * Scroll one unit.

     * @see notifyValue

     */

    void scroll() {

        switch (mode) {

          case AdjustmentEvent.UNIT_DECREMENT:

              notifyValue(val - line);

              return;

          case AdjustmentEvent.UNIT_INCREMENT:

              notifyValue(val + line);

              return;

          case AdjustmentEvent.BLOCK_DECREMENT:

              notifyValue(val - page);

              return;

          case AdjustmentEvent.BLOCK_INCREMENT:

              notifyValue(val + page);

              return;

        }

        return;

    }

    boolean isInArrow(int x, int y) {

        // Mouse is considered to be in the arrow if it is anywhere in the

        // arrow area.

        int coord = (alignment == ALIGNMENT_HORIZONTAL ? x : y);

        int arrAreaH = getArrowAreaWidth();

        if (coord < arrAreaH || coord > barLength - arrAreaH + 1) {

            return true;

        }

        return false;

    }

    /**

     * Is x,y in the scroll thumb?

     *

     * If we ever cache the thumb rect, we may need to clone the result of

     * calculateThumbRect().

     */

    boolean isInThumb(int x, int y) {

        Rectangle thumbRect = calculateThumbRect();

        // If the mouse is in the shadow of the thumb or the shadow of the

        // scroll track, treat it as hitting the thumb.  So, slightly enlarge

        // our rectangle.

        thumbRect.x -= 1;

        thumbRect.width += 3;

        thumbRect.height += 1;

        return thumbRect.contains(x,y);

    }

    abstract boolean beforeThumb(int x, int y);

    /**

     *

     * @see java.awt.event.MouseEvent

     * MouseEvent.MOUSE_CLICKED

     * MouseEvent.MOUSE_PRESSED

     * MouseEvent.MOUSE_RELEASED

     * MouseEvent.MOUSE_MOVED

     * MouseEvent.MOUSE_ENTERED

     * MouseEvent.MOUSE_EXITED

     * MouseEvent.MOUSE_DRAGGED

     */

    public void handleMouseEvent(int id, int modifiers, int x, int y) {

        if ((modifiers & InputEvent.BUTTON1_MASK) == 0) {

            return;

        }

             String type;

             switch (id) {

                case MouseEvent.MOUSE_PRESSED:

                    type = "press";

                    break;

                case MouseEvent.MOUSE_RELEASED:

                    type = "release";

                    break;

                case MouseEvent.MOUSE_DRAGGED:

                    type = "drag";

                    break;

                default:

                    type = "other";

             }

             log.finer("Mouse " + type + " event in scroll bar " + this +

                                                   "x = " + x + ", y = " + y +

                                                   ", on arrow: " + isInArrow(x, y) +

                                                   ", on thumb: " + isInThumb(x, y) + ", before thumb: " + beforeThumb(x, y)

                                                   + ", thumb rect" + calculateThumbRect());

        }

        switch (id) {

          case MouseEvent.MOUSE_PRESSED:

              if (isInArrow(x, y)) {

                  pressed = true;

                  if (beforeThumb(x, y)) {

                      mode = AdjustmentEvent.UNIT_DECREMENT;

                  } else {

                      mode = AdjustmentEvent.UNIT_INCREMENT;

                  }

                  sb.repaintScrollbarRequest(this);

                  startScrolling();

                  break;

              }

              if (isInThumb(x, y)) {

                  mode = AdjustmentEvent.TRACK;

              } else {

                  if (beforeThumb(x, y)) {

                      mode = AdjustmentEvent.BLOCK_DECREMENT;

                  } else {

                      mode = AdjustmentEvent.BLOCK_INCREMENT;

                  }

                  startScrolling();

              }

              Rectangle pos = calculateThumbRect();

              thumbOffset = new Point(x - pos.x, y - pos.y);

              break;

          case MouseEvent.MOUSE_RELEASED:

              pressed = false;

              sb.repaintScrollbarRequest(this);

              scroller.stop();

              if(dragging){

                  handleTrackEvent(x, y, false);

                  dragging=false;

              }

              break;

          case MouseEvent.MOUSE_DRAGGED:

              dragging = true;

              handleTrackEvent(x, y, true);

        }

    }

    private void handleTrackEvent(int x, int y, boolean isAdjusting){

        if (mode == AdjustmentEvent.TRACK) {

            notifyValue(calculateCursorOffset(x, y), isAdjusting);

        }

    }