/* ----------------------------------------------------------------------------
   The Kiwi Toolkit - A Java Class Library
   Copyright (C) 1998-2004 Mark A. Lindner

   This library 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 2 of the
   License, or (at your option) any later version.

   This library 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 library; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
   02111-1307, USA.
 
   The author may be contacted at: mark_a_lindner@yahoo.com
   ----------------------------------------------------------------------------
   $Log: LineChart.java,v $
   Revision 1.8  2004/05/05 22:24:14  markl
   comment block updates

   Revision 1.7  2003/11/07 19:16:52  markl
   Added get/setPointSpacing(), get/setPointRadius() methods.

   Revision 1.6  2003/01/19 09:33:21  markl
   Javadoc & comment header updates.

   Revision 1.5  2001/03/12 07:23:30  markl
   Javadoc cleanup.

   Revision 1.4  2000/10/17 20:43:10  markl
   Fixes to catch null values.

   Revision 1.3  2000/10/15 09:40:30  markl
   Added javadoc and final API polishing.

   Revision 1.2  2000/10/13 02:04:20  markl
   Added remaining classes, and integrated components with models.
   ----------------------------------------------------------------------------
*/

package kiwi.ui.graph;

import java.awt.*;
import java.util.*;
import javax.swing.*;

import kiwi.util.*;

/** A chart that renders the value of each variable as a series of points
 * connected by lines. This type of chart is used to illustrate trends across
 * data samples.
 *
 * <p><center><img src="snapshot/LineChart.gif"><br>
 * <i>An example LineChart.</i>
 * </center>
 *
 * @author Mark Lindner
 */

public class LineChart extends ChartView
  {
  private int pointSpacing = 40;
  private int pointRadius = 2;
  private int pointWidth;
  private int scaleWidth = 50;

  /** Construct a new <code>LineChart</code> for the specified chart
   * definition.
   *
   * @param chart The chart definition.
   */
  
  public LineChart(Chart chart)
    {
    super(chart);
    
    setOrientation(VERTICAL);
    setTickInterval(chart.getTickInterval());
    setPointRadius(2);
    }

  /** Set the point spacing (the space between points on the line, in pixels)
   *
   * @param spacing The new spacing. The value must be greater than zero.
   *
   * @since Kiwi 1.4.3
   */

  public void setPointSpacing(int spacing)
    {
    if(spacing > 0)
      pointSpacing = spacing;
    }

  /** Get the point spacing (the space between the points on the line, in
   * pixels.)
   *
   * @return The point spacing, in pixels.
   *
   * @since Kiwi 1.4.3
   */
  
  public int getPointSpacing()
    {
    return(pointSpacing);
    }

  /** Set the point radius (the size of a point on the line, in pixels)
   *
   * @param radius The new radius. The value must be greater than or equal
   * to zero.
   *
   * @since Kiwi 1.4.3
   */

  public void setPointRadius(int radius)
    {
    if(radius >= 0)
      pointRadius = radius;

    pointWidth = (pointRadius * 2) + 1;
    }
  
  /** Get the point radius (the size of a point on the line, in pixels)
   *
   * @return The point radius, in pixels.
   *
   * @since Kiwi 1.4.3
   */

  public int getPointRadius()
    {
    return(pointRadius);
    }
  
  /** Paint the chart.
   */
  
  protected void paintChart(Graphics gc)
    {
    int lx = 0, ly = 0, px, py;
    Dimension d = getSize();

    Enumeration e = chart.getValues();
    while(e.hasMoreElements())
      {
      boolean first = true;
      px = (horizontalPad * 2) + scaleWidth;      

      ChartValue cv = (ChartValue)e.nextElement();
      String var = cv.getName();
      gc.setColor(cv.getColor());

      Enumeration f = model.getDataSamples();
      while(f.hasMoreElements())
        {
        DataSample ds = (DataSample)f.nextElement();
        Object o = ds.getValue(var);
        double value = 0.0;
        if((o != null) && (o instanceof Number))
          value = ((Number)o).doubleValue();
          
        py = (int)(d.height - verticalPad - (value * scale));
        
        if(!first)
          gc.drawLine(lx, ly, px, py);

        gc.fillRect(px - pointRadius, py - pointRadius, pointWidth,
                    pointWidth);
        lx = px;
        ly = py;
        first = false;

        px += pointSpacing;
        }
      }

    drawVerticalScale(gc, horizontalPad + scaleWidth);    
    }

  /** Compute the maximum value.
   */

  protected double getMaxValue()
    {
    double maxval = 0.0;

    Enumeration e = chart.getValues();
    while(e.hasMoreElements())
      {
      ChartValue cv = (ChartValue)e.nextElement();
      String var = cv.getName();
      
      Enumeration f = model.getDataSamples();
      while(f.hasMoreElements())
        {
        DataSample ds = (DataSample)f.nextElement();
        Object o = ds.getValue(var);
        double value = 0.0;
        if((o != null) && (o instanceof Number))
          value = ((Number)o).doubleValue();

        if(value > maxval)
          maxval = value;
        }
      }

    return(maxval);
    }
  
  }

/* end of source file */