// updateApply applies an update of the ipfs binary and shuts down the node if successful
func updateApply(n *core.IpfsNode) (*UpdateOutput, error) {
	// TODO: 'force bool' param that stops the daemon (if running) before update

	output := &UpdateOutput{
		OldVersion: updates.Version,
	}

	u, err := updates.CheckForUpdate()
	if err != nil {
		return nil, err
	}

	if u == nil {
		output.NewVersion = updates.Version
		return output, nil
	}

	output.NewVersion = u.Version

	if n.OnlineMode() {
		return nil, errors.New(`You must stop the IPFS daemon before updating.`)
	}

	if err = updates.Apply(u); err != nil {
		return nil, err
	}

	return output, nil
}

func AddMetadataTo(n *core.IpfsNode, skey string, m *ft.Metadata) (string, error) {
	ukey := key.B58KeyDecode(skey)

	nd, err := n.DAG.Get(n.Context(), ukey)
	if err != nil {
		return "", err
	}

	mdnode := new(dag.Node)
	mdata, err := ft.BytesForMetadata(m)
	if err != nil {
		return "", err
	}

	mdnode.Data = mdata
	if err := mdnode.AddNodeLinkClean("file", nd); err != nil {
		return "", err
	}

	nk, err := n.DAG.Add(mdnode)
	if err != nil {
		return "", err
	}

	return nk.B58String(), nil
}

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

	return nil
}

// printing self is special cased as we get values differently.
func printSelf(node *core.IpfsNode) (interface{}, error) {
	info := new(IdOutput)
	info.ID = node.Identity.Pretty()

	if node.PrivateKey == nil {
		if err := node.LoadPrivateKey(); err != nil {
			return nil, err
		}
	}

	pk := node.PrivateKey.GetPublic()
	pkb, err := ic.MarshalPublicKey(pk)
	if err != nil {
		return nil, err
	}
	info.PublicKey = base64.StdEncoding.EncodeToString(pkb)

	if node.PeerHost != nil {
		for _, a := range node.PeerHost.Addrs() {
			s := a.String() + "/ipfs/" + info.ID
			info.Addresses = append(info.Addresses, s)
		}
	}
	info.ProtocolVersion = identify.IpfsVersion
	info.AgentVersion = identify.ClientVersion
	return info, nil
}

func Cat(n *core.IpfsNode, pstr string) (*uio.DagReader, error) {
	p := path.FromString(pstr)
	dagNode, err := n.Resolver.ResolvePath(n.Context(), p)
	if err != nil {
		return nil, err
	}
	return uio.NewDagReader(n.Context(), dagNode, n.DAG)
}

// Mount mounts ipfs at a given location, and returns a mount.Mount instance.
func Mount(ipfs *core.IpfsNode, mountpoint string) (mount.Mount, error) {
	cfg, err := ipfs.Repo.Config()
	if err != nil {
		return nil, err
	}
	allow_other := cfg.Mounts.FuseAllowOther
	fsys := NewFileSystem(ipfs)
	return mount.NewMount(ipfs.Process(), fsys, mountpoint, allow_other)
}

func Dial(nd *core.IpfsNode, p peer.ID, protocol string) (net.Stream, error) {
	ctx, cancel := context.WithTimeout(nd.Context(), time.Second*30)
	defer cancel()
	err := nd.PeerHost.Connect(ctx, peer.PeerInfo{ID: p})
	if err != nil {
		return nil, err
	}
	return nd.PeerHost.NewStream(pro.ID(protocol), p)
}

func addNode(n *core.IpfsNode, node *merkledag.Node) error {
	if err := n.DAG.AddRecursive(node); err != nil { // add the file to the graph + local storage
		return err
	}
	ctx, cancel := context.WithCancel(n.Context())
	defer cancel()
	err := n.Pinning.Pin(ctx, node, true) // ensure we keep it
	return err
}

func Metadata(n *core.IpfsNode, skey string) (*ft.Metadata, error) {
	ukey := key.B58KeyDecode(skey)

	nd, err := n.DAG.Get(n.Context(), ukey)
	if err != nil {
		return nil, err
	}

	return ft.MetadataFromBytes(nd.Data)
}

func getPaths(t *testing.T, ipfs *core.IpfsNode, name string, n *dag.Node) []string {
	if len(n.Links) == 0 {
		return []string{name}
	}
	var out []string
	for _, lnk := range n.Links {
		child, err := lnk.GetNode(ipfs.Context(), ipfs.DAG)
		if err != nil {
			t.Fatal(err)
		}
		sub := getPaths(t, ipfs, path.Join(name, lnk.Name), child)
		out = append(out, sub...)
	}
	return out
}

func Serve(node *core.IpfsNode, lis net.Listener, options ...ServeOption) error {
	handler, err := makeHandler(node, lis, options...)
	if err != nil {
		return err
	}

	addr, err := manet.FromNetAddr(lis.Addr())
	if err != nil {
		return err
	}

	// if the server exits beforehand
	var serverError error
	serverExited := make(chan struct{})

	node.Process().Go(func(p goprocess.Process) {
		serverError = http.Serve(lis, handler)
		close(serverExited)
	})

	// wait for server to exit.
	select {
	case <-serverExited:

	// if node being closed before server exits, close server
	case <-node.Process().Closing():
		log.Infof("server at %s terminating...", addr)

		lis.Close()

	outer:
		for {
			// wait until server exits
			select {
			case <-serverExited:
				// if the server exited as we are closing, we really dont care about errors
				serverError = nil
				break outer
			case <-time.After(5 * time.Second):
				log.Infof("waiting for server at %s to terminate...", addr)
			}
		}
	}

	log.Infof("server at %s terminated", addr)
	return serverError
}

func Listen(nd *core.IpfsNode, protocol string) (*ipfsListener, error) {
	ctx, cancel := context.WithCancel(nd.Context())

	list := &ipfsListener{
		proto:  pro.ID(protocol),
		conCh:  make(chan net.Stream),
		ctx:    ctx,
		cancel: cancel,
	}

	nd.PeerHost.SetStreamHandler(list.proto, func(s net.Stream) {
		select {
		case list.conCh <- s:
		case <-ctx.Done():
			s.Close()
		}
	})

	return list, nil
}

func addAssetList(nd *core.IpfsNode, l []string) (*key.Key, error) {
	dirb := uio.NewDirectory(nd.DAG)

	for _, p := range l {
		d, err := Asset(p)
		if err != nil {
			return nil, fmt.Errorf("assets: could load Asset '%s': %s", p, err)
		}

		s, err := coreunix.Add(nd, bytes.NewBuffer(d))
		if err != nil {
			return nil, fmt.Errorf("assets: could not Add '%s': %s", p, err)
		}

		fname := filepath.Base(p)
		k := key.B58KeyDecode(s)
		if err := dirb.AddChild(nd.Context(), fname, k); err != nil {
			return nil, fmt.Errorf("assets: could not add '%s' as a child: %s", fname, err)
		}
	}

	dir := dirb.GetNode()
	dkey, err := nd.DAG.Add(dir)
	if err != nil {
		return nil, fmt.Errorf("assets: DAG.Add(dir) failed: %s", err)
	}

	if err := nd.Pinning.Pin(nd.Context(), dir, true); err != nil {
		return nil, fmt.Errorf("assets: Pinning on init-docu failed: %s", err)
	}

	if err := nd.Pinning.Flush(); err != nil {
		return nil, fmt.Errorf("assets: Pinning flush failed: %s", err)
	}

	return &dkey, nil
}

func setupIpnsTest(t *testing.T, node *core.IpfsNode) (*core.IpfsNode, *fstest.Mount) {
	maybeSkipFuseTests(t)

	var err error
	if node == nil {
		node, err = core.NewNode(context.Background(), nil)
		if err != nil {
			t.Fatal(err)
		}

		err = node.LoadPrivateKey()
		if err != nil {
			t.Fatal(err)
		}

		node.Routing = offroute.NewOfflineRouter(node.Repo.Datastore(), node.PrivateKey)
		node.Namesys = namesys.NewNameSystem(node.Routing)

		ipnsfs, err := nsfs.NewFilesystem(context.Background(), node.DAG, node.Namesys, node.Pinning, node.PrivateKey)
		if err != nil {
			t.Fatal(err)
		}

		node.IpnsFs = ipnsfs
	}

	fs, err := NewFileSystem(node, node.PrivateKey, "", "")
	if err != nil {
		t.Fatal(err)
	}
	mnt, err := fstest.MountedT(t, fs)
	if err != nil {
		t.Fatal(err)
	}

	return node, mnt
}