/**
 * A ChoicePanel is a list of ChoiceChecks (see ChoiceCheck.java), each 
 * of which has a color that can be edited.  The background of all the
 * ChoiceCheck boxes should be that of the bgColor ChoiceCheck.  The
 * text of all the other ChoiceChecks should be the chosen color for
 * that ChoiceCheck.
 *
 * A bug in Java prevents the background of a ChoiceCheck from being
 * chosen unless that checkbox is checked.  So whenever bgColor is set,
 * we walk through all the ChoiceChecks and check them, then recheck
 * the bgColor. 
 *
 * Whatever class is actually manipulating colors doesn't know about
 * ChoicePanels.  It knows about the UseColor interface, and it is
 * handed this class as a UseColor, so that's how this gets notified
 * when colors are chosen.
 */

import java.awt.*;

final class ChoicePanel extends Panel implements UseColor {
  final int MAXCHOICES = 7;
  int numchoices;           /* number of choices the user actually asked for */
  int which;                              /* which color is being chosen now */
  ColorApplet   a;
  String      colors[];                                     /* colors chosen */
  String      names[];                                   /* names of choices */
  ChoiceCheck checks[];                                        /* checkboxes */

  ChoicePanel(ColorApplet a, int width, int height) {
    this.a = a;
    which = 0;
    colors = new String[MAXCHOICES];
    names = new String[MAXCHOICES];
    checks = new ChoiceCheck[MAXCHOICES];
    resize(width, height);
  }

  void init() {
    CheckboxGroup cbg = new CheckboxGroup();
    setBackground(Color.white);
    setLayout(new GridLayout(0, 1));
    for (numchoices = 0; names[numchoices] != null; ++numchoices) {
      if (colors[numchoices] == null)
	colors[numchoices] =
	  (names[numchoices].equals("bgColor")) ? "ffffff" : "808080";
      checks[numchoices] = new ChoiceCheck(
        names[numchoices], cbg, (numchoices==0), numchoices, this);
      add(checks[numchoices]);
    }
  }

  void setcolors() {
    if (names[which].equals("bgColor")) {
      Color nc = ColorApplet.s2c(colors[which]);
      setBackground(nc);
      if ((nc.getRGB() & 0x808080) != 0) {
	checks[which].setForeground(Color.black);
      } else {
	checks[which].setForeground(Color.white);
      }
      for (int j=0; j<numchoices; ++j) {
	checks[j].setBackground(nc);
      }
    } else {
      checks[which].setForeground(ColorApplet.s2c(colors[which]));
    }
  }

  /* callback, called by ColorPanel on each mouse click */
  public void UseColor(String newcolor) {
    colors[which] = newcolor;
    setcolors();
    for (int i=0; i<numchoices; ++i)
      checks[i].setState(i == which); 
  }
}