!7

cmodule2 > DynPrintLogAndEnabled {
  switchable double interval = 1.0; // seconds
  
  sclass Entry {
    long threadID;
    S threadName;
    WeakRef<Thread> thread;
    StackTraceElement[] stackTrace;
    bool runnable;
  }
  
  transient L<Entry> entries;
  transient volatile Map<Thread, StackTraceElement[]> stackTraces; // weakHashMap
  transient volatile Map<Thread, StackTraceElement[]> runnableStackTraces;
  
  start {
    dm_reloadOnFieldChange enabled();
    if (enabled) dm_doEvery(interval, r {
      if (!enabled) ret;
      
      var raw = allThreadsWithStackTraces();
      setField(entries := map(raw, (t, st) -> {
        new Entry e;
        e.threadID = threadID(t);
        e.threadName = threadName(t);
        e.thread = weakRef(t);
        e.stackTrace = st;
        e.runnable = isThreadRunnable_x(t, st);
      }));
      
      setField(stackTraces := toWeakHashMap(raw));
      setField(runnableStackTraces := mapToWeakHashMap(filter(entries, e -> e.runnable), e -> pair(e.thread!, e.stackTrace)));
        
      vmBus_send freshStackTraces(stackTraces, weakRef(me()));
    });
  }
  
  S renderStats() { ret stackTraces == null ? ""
    : n2(stackTraces, "thread") + " / " + n2(runnableStackTraces) + " runnable";
  }
  
  visual dm_calculatedCenteredLabel renderStats();
}