// (c)1996 JRad Technologies
// Free to use, can't redistribute for profit
//
// Original by Pete Yared.
// Modified by Jean-Guy Speton (speton@cs.orst.edu).
//   Version 1.0.
//   * Changed name to TabPanel to differentiate modification tree
//     from original.
//   * JDK 1.1 API compliant.
//   * CardLayout used to simplify implementation.
//   * Added getMinimumSize() and getPreferredSize().
//   * Tab Font stored in state and created only once.
//   * Tab in index 0 now default selected.
//   * No longer repaints when user reselects selected tab.
// Still free to use, still can't redistribute for profit.

import java.awt.*;
import java.awt.event.*;
import java.util.Vector;

public class TabPanel extends Panel implements MouseListener
{
  protected Vector labels = new Vector();
  protected Vector panels = new Vector();

  protected Panel cardPanel = new Panel();
  
  protected int[] tabWidths;
  protected String selectedPanel;

  protected Font tabFont = new Font("Dialog", 12, Font.PLAIN);

  protected Insets insets;
  protected int tabHeight = 21;
  protected int tabWidthBuffer = 13;

  protected int insetPadding = 14;

  public TabPanel()
  {
    insets = new Insets(insetPadding + tabHeight, insetPadding,
			insetPadding, insetPadding);
    setLayout(null);
    addMouseListener(this);

    cardPanel.setLayout(new CardLayout());
    add(cardPanel);
  }

  //
  // MouseListener interface.
  //
  
  public void mousePressed(MouseEvent event)
  {
    if (event.getY() < tabHeight) {
      int xLoc = 0;
      for (int i = 0; i < labels.size(); i++) {
	xLoc += tabWidths[i];
	if (event.getX() < xLoc) {
	  setPanel((String)labels.elementAt(i));
	  return;
	}
      }
    }
  }
  public void mouseReleased(MouseEvent event) {}
  public void mouseEntered(MouseEvent event) {}
  public void mouseExited(MouseEvent event) {}
  public void mouseClicked(MouseEvent event) {}

  //
  // Methods.
  //
  
  public Dimension getMinimumSize()
  {
    int w = 0;
    int h = 0;

    FontMetrics metrics = getFontMetrics(tabFont);
    for (int i = 0; i < labels.size(); i++) {
      w += metrics.stringWidth((String)labels.elementAt(i)) + tabWidthBuffer;
    }

    for (int i = 0; i < panels.size(); i++) {
      Dimension d = ((Panel)panels.elementAt(i)).getMinimumSize();
      w = Math.max(w, d.width + insets.left + insets.right);
      h = Math.max(h, d.height);
    }

    h += insets.top + insets.bottom;
    
    return new Dimension(w, h);
  }

  public Dimension getPreferredSize()
  {
    return getMinimumSize();
  }

  public void setBounds(int nx, int ny, int nw, int nh)
  {
    cardPanel.setBounds(insets.left,
			insets.top,
			nw - insets.left - insets.right,
			nh - insets.top - insets.bottom);
    super.setBounds(nx, ny, nw, nh);
  }

  public void addPanel(Panel panel, String label)
  {
    labels.addElement(label);
    panels.addElement(panel);
    cardPanel.add(label, panel);

    if (panels.size() == 1) {
      selectedPanel = label;
    }
  }

  public void removePanel(String label)
  {
    int index = labels.indexOf(label);
    if (index == -1) {
      throw new IllegalArgumentException(label +
					 " is not a panel in this TabPanel");
    }
    labels.removeElementAt(index);
    panels.removeElementAt(index);
    if (label.equals(selectedPanel)) {
      if (labels.size() > 0)
	setPanel((String) labels.elementAt(0));
      else
	selectedPanel = null;
    }
  }

  public void setPanel(String label)
  {
    if (label.equals(selectedPanel)) {
      return;
    }
    
    selectedPanel = label;
    ((CardLayout)cardPanel.getLayout()).show(cardPanel, label);

    repaint();
  }

  public String getSelectedPanelName()
  {
    return this.selectedPanel;
  }

  public Panel getSelectedPanel()
  {
    return (Panel)panels.elementAt(labels.indexOf(selectedPanel));
  }

  public Insets getInsets()
  {
    return insets;
  }

  public void setInsets(Insets insets)
  {
    this.insets = insets;
  }

  public int getTabHeight()
  {
    return this.tabHeight;
  }

  public void setTabHeight(int tabHeight)
  {
    this.tabHeight = tabHeight;
  }

  public int getTabWidthBuffer()
  {
    return this.tabWidthBuffer;
  }

  public void setTabWidthBuffer(int tabWidthBuffer)
  {
    this.tabWidthBuffer = tabWidthBuffer;
  }

  public void paint(Graphics g)
  {
    super.paint(g);

    int top = tabHeight - 1;
    int left = 0;
    int bottom = getSize().height - 1;
    int right = left + getSize().width - 1;

    g.setColor(Color.darkGray);
    g.drawLine(left, bottom, right - 1, bottom); // Bottom left to bottom right
    g.drawLine(right, top, right, bottom);       // Topright to bottomright

    g.setColor(Color.gray);
    g.drawLine(left + 1, bottom - 1, right - 2, bottom - 1); // Bottom left to bottom right
    g.drawLine(right - 1, top + 1, right - 1, bottom - 1);   // Topright to bottomright

    g.setColor(Color.white);
    g.drawLine(left, top, left, bottom - 1); // Topleft to bottomleft

    tabWidths = new int[labels.size()];
    int selected = -1;
    int selectedLoc = 0;
    int xLoc = 2;
    for (int i = 0; i < labels.size(); i++) {
      String label = (String) labels.elementAt(i);
      FontMetrics metrics = getFontMetrics(tabFont);
      tabWidths[i] = metrics.stringWidth(label) + tabWidthBuffer;
      if (labels.elementAt(i).equals(selectedPanel)) {
	selected = i;
	selectedLoc = xLoc;
      }
      else {
	paintTab(g, false, xLoc, 0, tabWidths[i], top, label);
      }
      xLoc += tabWidths[i] - 1;
    }
    if (selected > -1) {
      paintTab(g, true, selectedLoc, 0, tabWidths[selected], top,
	       (String) labels.elementAt(selected));
      g.setColor(Color.white);
      g.drawLine(left, top, selectedLoc - 2, top); // Topleft to topright - left side
      g.drawLine(selectedLoc + tabWidths[selected] + 2, top, right - 1,
		 top);       // Topleft to topright - right side
    }
    else {
      g.setColor(Color.white);
      g.drawLine(left, top, right - 1, top); // Topleft to topright
    }
  }

  private void paintTab(Graphics g, boolean selected, int x, int y, int
			width, int height, String label)
  {
    int left = x;
    int top = y + 2;
    int right = x + width - 1;
    int bottom = y + height - 1;

    height -= 2;

    if (selected) {
      top -= 2;
      left -= 2;
      right += 2;
      bottom += 1;
    }

    g.setColor(Color.darkGray);
    g.drawLine(right - 1, top + 2, right - 1, bottom); // Topright to bottomright
    g.drawRect(right - 2, top + 1, 0, 0);              // Topright corner

    g.setColor(Color.gray);
    g.drawLine(right - 2, top + 2, right - 2, bottom); // Topright to bottomright
    
    g.setColor(Color.white);
    g.drawLine(left, top + 2, left, bottom);   // Topleft to bottomleft
    g.drawLine(left + 2, top, right - 3, top); // Topleft to topright
    g.drawRect(left + 1, top + 1, 0, 0);       // Topleft corner

    g.setColor(Color.black);

    FontMetrics metrics = g.getFontMetrics(tabFont);
    g.setFont(tabFont);
    g.drawString(label, x + ((width - metrics.stringWidth(label)) / 2),
		 metrics.getHeight() + top + 1);

    if (selected) {
      g.setColor(getBackground());
      g.drawLine(left + 1, bottom, right - 3, bottom); // Bottomleft to bottomright
      g.drawLine(left + 1, top + 3, left + 1, bottom); // Topleft to bottomleft indented by one
    }
  }
}