// 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
}

// Publish publishes the ipns entry associated with this key
func (kr *KeyRoot) Publish(ctx context.Context) error {
	child, ok := kr.val.(FSNode)
	if !ok {
		return errors.New("child of key root not valid type")
	}

	nd, err := child.GetNode()
	if err != nil {
		return err
	}

	// Holding this lock so our child doesnt change out from under us
	child.Lock()
	k, err := kr.fs.dserv.Add(nd)
	if err != nil {
		child.Unlock()
		return err
	}
	child.Unlock()
	// Dont want to hold the lock while we publish
	// otherwise we are holding the lock through a costly
	// network operation

	kp := path.FromKey(k)

	ev := &logging.Metadata{"name": kr.name, "key": kp}
	defer log.EventBegin(ctx, "ipnsfsPublishing", ev).Done()
	log.Info("ipnsfs publishing %s -> %s", kr.name, kp)

	return kr.fs.nsys.Publish(ctx, kr.key, kp)
}

// InitializeKeyspace sets the ipns record for the given key to
// point to an empty directory.
func InitializeKeyspace(n *core.IpfsNode, key ci.PrivKey) error {
	emptyDir := &mdag.Node{Data: ft.FolderPBData()}
	nodek, err := n.DAG.Add(emptyDir)
	if err != nil {
		return err
	}

	ctx, cancel := context.WithCancel(n.Context())
	defer cancel()

	err = n.Pinning.Pin(ctx, emptyDir, false)
	if err != nil {
		return err
	}

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

	pub := nsys.NewRoutingPublisher(n.Routing, n.Repo.Datastore())
	if err := pub.Publish(ctx, key, path.FromKey(nodek)); err != nil {
		return err
	}

	return nil
}

// Publish publishes the ipns entry associated with this key
func (kr *KeyRoot) Publish(ctx context.Context) error {
	child, ok := kr.val.(FSNode)
	if !ok {
		return errors.New("child of key root not valid type")
	}

	nd, err := child.GetNode()
	if err != nil {
		return err
	}

	// Holding this lock so our child doesnt change out from under us
	child.Lock()
	k, err := kr.fs.dserv.Add(nd)
	if err != nil {
		child.Unlock()
		return err
	}
	child.Unlock()
	// Dont want to hold the lock while we publish
	// otherwise we are holding the lock through a costly
	// network operation

	fmt.Println("Publishing!")
	return kr.fs.nsys.Publish(ctx, kr.key, path.FromKey(k))
}

// resolveOnce implements resolver. Uses the IPFS routing system to
// resolve SFS-like names.
func (r *routingResolver) resolveOnce(ctx context.Context, name string) (path.Path, error) {
	log.Debugf("RoutingResolve: '%s'", name)
	hash, err := mh.FromB58String(name)
	if err != nil {
		log.Warning("RoutingResolve: bad input hash: [%s]\n", name)
		return "", err
	}
	// name should be a multihash. if it isn't, error out here.

	// use the routing system to get the name.
	// /ipns/<name>
	h := []byte("/ipns/" + string(hash))

	ipnsKey := key.Key(h)
	val, err := r.routing.GetValue(ctx, ipnsKey)
	if err != nil {
		log.Warning("RoutingResolve get failed.")
		return "", err
	}

	entry := new(pb.IpnsEntry)
	err = proto.Unmarshal(val, entry)
	if err != nil {
		return "", err
	}

	// name should be a public key retrievable from ipfs
	pubkey, err := routing.GetPublicKey(r.routing, ctx, hash)
	if err != nil {
		return "", err
	}

	hsh, _ := pubkey.Hash()
	log.Debugf("pk hash = %s", key.Key(hsh))

	// check sig with pk
	if ok, err := pubkey.Verify(ipnsEntryDataForSig(entry), entry.GetSignature()); err != nil || !ok {
		return "", fmt.Errorf("Invalid value. Not signed by PrivateKey corresponding to %v", pubkey)
	}

	// ok sig checks out. this is a valid name.

	// check for old style record:
	valh, err := mh.Cast(entry.GetValue())
	if err != nil {
		// Not a multihash, probably a new record
		return path.ParsePath(string(entry.GetValue()))
	} else {
		// Its an old style multihash record
		log.Warning("Detected old style multihash record")
		return path.FromKey(key.Key(valh)), nil
	}
}

func (node *Node) Unpin(hash multihash.Multihash) error {
	nd, err := node.proc()
	if err != nil {
		return err
	}

	paths := []string{path.FromKey(key.Key(hash)).String()}
	if _, err := corerepo.Unpin(nd, node.Context, paths, true); err != nil {
		return err
	}

	return nil
}

func (node *Node) Pin(hash multihash.Multihash) error {
	nd, err := node.proc()
	if err != nil {
		return err
	}

	defer nd.Blockstore.PinLock().Unlock()

	paths := []string{path.FromKey(key.Key(hash)).String()}
	if _, err := corerepo.Pin(nd, node.Context, paths, true); err != nil {
		return err
	}

	return nil
}

func (i *gatewayHandler) deleteHandler(w http.ResponseWriter, r *http.Request) {
	urlPath := r.URL.Path
	ctx, cancel := context.WithCancel(i.node.Context())
	defer cancel()

	ipfsNode, err := core.Resolve(ctx, i.node, path.Path(urlPath))
	if err != nil {
		// FIXME HTTP error code
		webError(w, "Could not resolve name", err, http.StatusInternalServerError)
		return
	}

	k, err := ipfsNode.Key()
	if err != nil {
		webError(w, "Could not get key from resolved node", err, http.StatusInternalServerError)
		return
	}

	h, components, err := path.SplitAbsPath(path.FromKey(k))
	if err != nil {
		webError(w, "Could not split path", err, http.StatusInternalServerError)
		return
	}

	tctx, cancel := context.WithTimeout(ctx, time.Minute)
	defer cancel()
	rootnd, err := i.node.Resolver.DAG.Get(tctx, key.Key(h))
	if err != nil {
		webError(w, "Could not resolve root object", err, http.StatusBadRequest)
		return
	}

	pathNodes, err := i.node.Resolver.ResolveLinks(tctx, rootnd, components[:len(components)-1])
	if err != nil {
		webError(w, "Could not resolve parent object", err, http.StatusBadRequest)
		return
	}

	// TODO(cyrptix): assumes len(pathNodes) > 1 - not found is an error above?
	err = pathNodes[len(pathNodes)-1].RemoveNodeLink(components[len(components)-1])
	if err != nil {
		webError(w, "Could not delete link", err, http.StatusBadRequest)
		return
	}

	newnode := pathNodes[len(pathNodes)-1]
	for i := len(pathNodes) - 2; i >= 0; i-- {
		newnode, err = pathNodes[i].UpdateNodeLink(components[i], newnode)
		if err != nil {
			webError(w, "Could not update node links", err, http.StatusInternalServerError)
			return
		}
	}

	if err := i.node.DAG.AddRecursive(newnode); err != nil {
		webError(w, "Could not add recursively new node", err, http.StatusInternalServerError)
		return
	}

	// Redirect to new path
	key, err := newnode.Key()
	if err != nil {
		webError(w, "Could not get key of new node", err, http.StatusInternalServerError)
		return
	}

	i.addUserHeaders(w) // ok, _now_ write user's headers.
	w.Header().Set("IPFS-Hash", key.String())
	http.Redirect(w, r, gopath.Join(ipfsPathPrefix+key.String(), path.Join(components[:len(components)-1])), http.StatusCreated)
}

		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		node, err := core.Resolve(req.Context(), n, p)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		key, err := node.Key()
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		res.SetOutput(&ResolvedPath{path.FromKey(key)})
	},
	Marshalers: cmds.MarshalerMap{
		cmds.Text: func(res cmds.Response) (io.Reader, error) {
			output, ok := res.Output().(*ResolvedPath)
			if !ok {
				return nil, u.ErrCast()
			}
			return strings.NewReader(output.Path.String() + "\n"), nil
		},
	},
	Type: ResolvedPath{},
}

func ipnsPubFunc(ipfs *core.IpfsNode, k ci.PrivKey) mfs.PubFunc {
	return func(ctx context.Context, key key.Key) error {
		return ipfs.Namesys.Publish(ctx, k, path.FromKey(key))
	}
}

func (i *gatewayHandler) putHandler(w http.ResponseWriter, r *http.Request) {
	// TODO(cryptix): either ask mildred about the flow of this or rewrite it
	webErrorWithCode(w, "Sorry, PUT is bugged right now, closing request", errors.New("handler disabled"), http.StatusInternalServerError)
	return
	urlPath := r.URL.Path
	pathext := urlPath[5:]
	var err error
	if urlPath == ipfsPathPrefix+"QmUNLLsPACCz1vLxQVkXqqLX5R1X345qqfHbsf67hvA3Nn/" {
		i.putEmptyDirHandler(w, r)
		return
	}

	var newnode *dag.Node
	if pathext[len(pathext)-1] == '/' {
		newnode = uio.NewEmptyDirectory()
	} else {
		newnode, err = i.newDagFromReader(r.Body)
		if err != nil {
			webError(w, "Could not create DAG from request", err, http.StatusInternalServerError)
			return
		}
	}

	ctx, cancel := context.WithCancel(i.node.Context())
	defer cancel()

	ipfsNode, err := core.Resolve(ctx, i.node, path.Path(urlPath))
	if err != nil {
		// FIXME HTTP error code
		webError(w, "Could not resolve name", err, http.StatusInternalServerError)
		return
	}

	k, err := ipfsNode.Key()
	if err != nil {
		webError(w, "Could not get key from resolved node", err, http.StatusInternalServerError)
		return
	}

	h, components, err := path.SplitAbsPath(path.FromKey(k))
	if err != nil {
		webError(w, "Could not split path", err, http.StatusInternalServerError)
		return
	}

	if len(components) < 1 {
		err = fmt.Errorf("Cannot override existing object")
		webError(w, "http gateway", err, http.StatusBadRequest)
		return
	}

	tctx, cancel := context.WithTimeout(ctx, time.Minute)
	defer cancel()
	// TODO(cryptix): could this be core.Resolve() too?
	rootnd, err := i.node.Resolver.DAG.Get(tctx, key.Key(h))
	if err != nil {
		webError(w, "Could not resolve root object", err, http.StatusBadRequest)
		return
	}

	// resolving path components into merkledag nodes. if a component does not
	// resolve, create empty directories (which will be linked and populated below.)
	pathNodes, err := i.node.Resolver.ResolveLinks(tctx, rootnd, components[:len(components)-1])
	if _, ok := err.(path.ErrNoLink); ok {
		// Create empty directories, links will be made further down the code
		for len(pathNodes) < len(components) {
			pathNodes = append(pathNodes, uio.NewDirectory(i.node.DAG).GetNode())
		}
	} else if err != nil {
		webError(w, "Could not resolve parent object", err, http.StatusBadRequest)
		return
	}

	for i := len(pathNodes) - 1; i >= 0; i-- {
		newnode, err = pathNodes[i].UpdateNodeLink(components[i], newnode)
		if err != nil {
			webError(w, "Could not update node links", err, http.StatusInternalServerError)
			return
		}
	}

	err = i.node.DAG.AddRecursive(newnode)
	if err != nil {
		webError(w, "Could not add recursively new node", err, http.StatusInternalServerError)
		return
	}

	// Redirect to new path
	key, err := newnode.Key()
	if err != nil {
		webError(w, "Could not get key of new node", err, http.StatusInternalServerError)
		return
	}

	i.addUserHeaders(w) // ok, _now_ write user's headers.
	w.Header().Set("IPFS-Hash", key.String())
	http.Redirect(w, r, ipfsPathPrefix+key.String()+"/"+strings.Join(components, "/"), http.StatusCreated)
}