!7

concept CalendarEntry {
  int year, month, day;
  S text;
}

module Calendar > DynSCP {
  int year = localYear(), month = localMonth();

  start {
    dbIndexing(CalendarEntry, 'year);
    onChange(r revisualize2);
  }
  
  visualize {
    ret northAndCenterWithMargins(rightAlignedLine(
      dm_fieldSpinner('year, 1970, 2030)),
      super.visualize());
  }
  
  visualize2 {
    setModuleName("Calendar (" + month + "/" + year + ")");
    int days = daysInMonth(year, month);
    int weekDay = dayOfWeek_nr(calendarFromYMD(year, month, 1))-1;
    print("Weekday " + year + "/" + month + "/" + 1 + ": " + weekDay);
    new LL<Component> rows;
    rows.add(map(intRangeList(7), func(int i) -> Component {
      jcenteredlabel(shortEnglishWeekdays().get(i)) }));
    rows.add(new L);
    Map<Int, CalendarEntry> entries = indexByField day(conceptsWhere(CalendarEntry, +year, +month));
    for (int i = 1; i <= days; i++) {
      if (l(last(rows)) > weekDay) rows.add(new L);
      while (weekDay > l(last(rows))) last(rows).add(jlabel());
      JLabel lbl = jcenteredlabel(str(i));
      if (entries.containsKey(i))
        setOpaqueBackground(Color.GREEN, lbl);
      last(rows).add(lbl);
      weekDay = (weekDay+1) % 7;
    }
    while (l(last(rows)) < 7) last(rows).add(jlabel());
    ret hvgrid(rows);
  }
}