srecord noeq G22ChallengePanel(G22Challenge challenge) extends HasChangeListeners is Swingable {

  settableWithChange long randomSeed = 1; //randomUnsignedInt();

  //transient JPanel imagesPanel = jline();

  transient DynamicHStack imagesPanel;

  transient L<Entry> entries = syncL();

  transient JComponent imagesSection;

  transient GazelleV_LeftArrowScript.Script parsedScript;

  settableWithChange Set<Class> solutionTypes = syncSet();

  transient settable new G22Utils g22utils;

  settable double timeoutPerImage = 10.0;

  settable int imagesToPaint = 3;

  settable int interval = 100;

  settable int imageDisplaySize = 100;

  settable Color imageBorderColor1 = Color.green;

  settable Color imageBorderColor2 = Color.red;

  settable int imageBorderSize = 1;

  visualize {

    imagesPanel = (DynamicHStack) dynamicHStack().spacing(20);

    awtCalcEvery(imagesPanel, interval, r _paintAnImage);

    ret withCenteredBoldTitle(str(challenge),

      withTopMargin(jvsplit(

        northAndCenterWithMargin(

          centerAndEastWithMargin(

            centeredLiveValueLabel(

              liveValue_hasChangeListeners(this,

                -> "Looking for: " + solutionTypeDesc())),

            swing(-> JPopDownButton(menu ->

              menu.add(jMenuItem("Random seed: " + n2(randomSeed)))))

          ),

          imagesSection = jCenteredRaisedSection("Images", jBorderlessHigherScrollPane(jfullcenter(imagesPanel))),

          /*jRightAlignedLine(

            withLabel("Random seed:",

              liveValueLabel(liveValue_hasChangeListeners(this, -> randomSeed)))),*/

        ),

        jCenteredSection("Analysis",

          jTodo()

        )

      )));

  }

  void _paintAnImage {

    if (l(entries) >= imagesToPaint) ret;

    int index = l(entries)+1;

    Entry entry = new(index, (int) (randomSeed+index-1));

    entries.add(entry);

    try {

      if (parsedScript == null) {

        var parser = g22utils.leftArrowParser();

        parsedScript = parser.parse(challenge.code);

      }

      new VarContext ctx;

      var result = evalWithTimeout(timeoutPerImage, -> {

        temp tempSetRandomSeed((int) entry.seed);

        ret parsedScript.get(ctx);

      });

      if (result.isA()) {

        var returnedObject = result.a();

        if (returnedObject instanceof MakesBufferedImage

          || returnedObject instanceof Image)

          returnedObject = toBufferedImage(returnedObject);

        if (returnedObject cast BufferedImage) {

          entry.solution(ctx.get("solution"));

          updateSolutionType(entry.solution);

          addImage(entry, returnedObject);

        } else {

          addImage(entry, null, jcenteredlabel("Script did not return an image but instead " + aOrAn(className(returnedObject))));

        }

      } else {

        addImage(entry, null, jcenteredlabel("Script timed out after " + nSeconds(iceil(timeoutPerImage))));

      }

    } catch print e {

      entry.error(e);

      addImage(entry, null, jError(e));

    } finally {

      entry.calculating(false);

    }

  }

  void addImage(Entry entry, BufferedImage image, JComponent component) {

    entry.image(image).component(component);

    addAndRevalidate(imagesPanel, component);

    setSectionTitle(imagesSection, firstToUpper(nImages(entries)) + " calculated");

  }

  void addImage(Entry entry, BufferedImage image) {

    entry.image(image);

    addImage(entry, image, imageToComponent(entry));

  }

  JComponent imageToComponent(Entry entry) {

    var image = entry.image;

    // var is = g22utils.stdImageSurface(image);

    // jFixedSize(image.getWidth(), image.getHeight(), is);

    // ret is;

    double scale = calcFitScale(image, imageDisplaySize);

    var image2 = scaleImageWithOp(image, scale,

      AffineTransformOp.TYPE_NEAREST_NEIGHBOR);

    for (color : ll(imageBorderColor1, imageBorderColor2))

      image2 = addBorderToImage(image2, color, imageBorderSize);

    S toolTip = "Image " + n2(entry.index) + " of " + challenge + " (seed " + n2(entry.seed) + ", " + image.getWidth() + "*" + image.getHeight() + " px)";

    JButton b = withToolTip(toolTip, jimageButton(image2));

    setMargin(10, b);

    ret b;

  }

  class Entry {

    int index; // index in sequence starting with 1

    long seed; // seed for randomizer

    settable BufferedImage image;

    settable Throwable error;

    settable O solution;

    settable bool calculating = true;

    settable JComponent component;

    *(int *index, long *seed) {}

  }

  void updateSolutionType(O solution) {

    Class c = _getClass(solution);

    if (solutionTypes.add(c)) change();

  }

  S solutionTypeDesc() {

    LS types = map solutionTypeDesc(solutionTypes);

    ret textOut_or(types, "Calculating...");

  }

  S solutionTypeDesc(Class c) {

    if (c == null)

      ret "no solution given";

    if (c == Rect)

      ret "a rectangular area in the image";

    ret aOrAn(shortClassName(c));

  }

}