!7

static LPair<IntRange> arrows = synchroList();

p-experiment {

  S text = lines(sentencesAfterLines_withPeriodOnly(mechList_raw("Simple Wikipedia: Peafowl")));

  //jtextpane(text)

  JTextPane tp = swing(func -> JTextPane {

    ret new JTextPane {

      public void paint(Graphics _g) {

        Graphics2D g = cast _g;

        super.paint(g);

        pcall {

          Color arrowColor = colorWithAlpha(Color.red, 0.3);

          S text = getText();

          for (Pair<IntRange> p : cloneList(arrows)) {

            Rect r1 = textComponent_substringRect(this, p.a);

            Rect r2 = textComponent_substringRect(this, p.b);

            if (r1 != null && r2 != null) {

              fillRect(g, r1, colorWithAlpha(Color.green, 0.2));

              fillRect(g, r2, colorWithAlpha(Color.red, 0.2));

              //drawArrowBetweenRects(g, r1, r2, arrowColor);

              drawArrowBetweenPoints(g, centerOfRect(r1), centerOfRect(r2), arrowColor);

            } else if (r1 != null)

              drawText(g, "?", centerTextInRect(g.getFontMetrics(), "?", r1), arrowColor);

          }

        }

      }

    };

  });

  setTextCaret0(tp, text);

  L<S> tok = javaTok(text);

  addPair(arrows,

    tokenToCharRange(tok, indexOfIC(tok, "it")),

    tokenToCharRange(tok, indexOfIC(tok, "peafowl")));

  Set<S> set = mechSetCI("Backreferencing words");

  Set<IntRange> have = asHashSet(firstOfPairs(arrows));

  for (int i = 1; i < l(tok); i += 2)

    if (set.contains(tok.get(i)) && !arrows.contains(tokenToCharRange(tok, i)))

      addPair(arrows, tokenToCharRange(tok, i), null); // show question mark

  showFrame(setFontSize(30, tp));

  hideConsole();

}