!7

concept Slurpable {
  S videoID;
  bool slurped;
}

cmodule YouTubeSurfer > DynPrintLogAndEnabled {
  switchable double interval = 10.0;

  start-thread {
    dbIndexing(Slurpable, 'videoID);
    if (noConcepts(Slurpable)) addVideoID("GKvMhYCJA-c");
    doEvery(interval, rEnter { if (enabled) slurpOne() });
    print("URLs: " + countConcepts(Slurpable) + ", slurpable: " + l(urlsToSlurp()));
    print("Fetch interval: " + interval + " s");
  }
  
  void addVideoID(S videoID) {
    uniq Slurpable(+videoID);
  }
  
  Cl<Slurpable> urlsToSlurp() {
    ret conceptsWhere(Slurpable, slurped := false);
  }
  
  void slurpOne {
    Slurpable s = random(urlsToSlurp()), ret if null;
    for (PairS p : videoLinksFromYouTubePage(s.videoID))
      addVideoID(p.a);
    cset(s, slurped := true);
  }
}