// InitializeKeyspace sets the ipns record for the given key to
// point to an empty directory.
// TODO: this doesnt feel like it belongs here
func InitializeKeyspace(ctx context.Context, ds dag.DAGService, pub Publisher, pins pin.Pinner, key ci.PrivKey) error {
	emptyDir := &dag.Node{Data: ft.FolderPBData()}
	nodek, err := ds.Add(emptyDir)
	if err != nil {
		return err
	}

	// pin recursively because this might already be pinned
	// and doing a direct pin would throw an error in that case
	err = pins.Pin(ctx, emptyDir, true)
	if err != nil {
		return err
	}

	err = pins.Flush()
	if err != nil {
		return err
	}

	err = pub.Publish(ctx, key, path.FromKey(nodek))
	if err != nil {
		return err
	}

	return nil
}

func FilterPinned(pins pin.Pinner, out chan<- interface{}, cids []*cid.Cid) []*cid.Cid {
	stillOkay := make([]*cid.Cid, 0, len(cids))
	res, err := pins.CheckIfPinned(cids...)
	if err != nil {
		out <- &RemovedBlock{Error: fmt.Sprintf("pin check failed: %s", err)}
		return nil
	}
	for _, r := range res {
		if !r.Pinned() {
			stillOkay = append(stillOkay, r.Key)
		} else {
			out <- &RemovedBlock{
				Hash:  r.Key.String(),
				Error: r.String(),
			}
		}
	}
	return stillOkay
}

func ColoredSet(ctx context.Context, pn pin.Pinner, ds dag.DAGService, bestEffortRoots []key.Key) (key.KeySet, error) {
	// KeySet currently implemented in memory, in the future, may be bloom filter or
	// disk backed to conserve memory.
	gcs := key.NewKeySet()
	err := Descendants(ctx, ds, gcs, pn.RecursiveKeys(), false)
	if err != nil {
		return nil, err
	}

	err = Descendants(ctx, ds, gcs, bestEffortRoots, true)
	if err != nil {
		return nil, err
	}

	for _, k := range pn.DirectKeys() {
		gcs.Add(k)
	}

	err = Descendants(ctx, ds, gcs, pn.InternalPins(), false)
	if err != nil {
		return nil, err
	}

	return gcs, nil
}