func TestQueryCallsLast(t *testing.T) {
	var d1n, d2n, d3n int
	d1 := dscb.Wrap(ds.NewMapDatastore(), func() { d1n++ })
	d2 := dscb.Wrap(ds.NewMapDatastore(), func() { d2n++ })
	d3 := dscb.Wrap(ds.NewMapDatastore(), func() { d3n++ })

	td := New(d1, d2, d3)

	td.Query(dsq.Query{})
	if d3n < 1 {
		t.Error("should call last")
	}
}

func (rs *s) ClientWithDatastore(_ context.Context, p testutil.Identity, datastore ds.Datastore) Client {
	return &client{
		peer:      p,
		datastore: ds.NewMapDatastore(),
		server:    rs,
	}
}

func TestDuplicateSemantics(t *testing.T) {
	ctx := context.Background()
	dstore := dssync.MutexWrap(ds.NewMapDatastore())
	bstore := blockstore.NewBlockstore(dstore)
	bserv := bs.New(bstore, offline.Exchange(bstore))

	dserv := mdag.NewDAGService(bserv)

	// TODO does pinner need to share datastore with blockservice?
	p := NewPinner(dstore, dserv)

	a, _ := randNode()
	_, err := dserv.Add(a)
	if err != nil {
		t.Fatal(err)
	}

	// pin is recursively
	err = p.Pin(ctx, a, true)
	if err != nil {
		t.Fatal(err)
	}

	// pinning directly should fail
	err = p.Pin(ctx, a, false)
	if err == nil {
		t.Fatal("expected direct pin to fail")
	}

	// pinning recursively again should succeed
	err = p.Pin(ctx, a, true)
	if err != nil {
		t.Fatal(err)
	}
}

func (cfg *BuildCfg) fillDefaults() error {
	if cfg.Repo != nil && cfg.NilRepo {
		return errors.New("cannot set a repo and specify nilrepo at the same time")
	}

	if cfg.Repo == nil {
		var d ds.Datastore
		d = ds.NewMapDatastore()
		if cfg.NilRepo {
			d = ds.NewNullDatastore()
		}
		r, err := defaultRepo(dsync.MutexWrap(d))
		if err != nil {
			return err
		}
		cfg.Repo = r
	}

	if cfg.Routing == nil {
		cfg.Routing = DHTOption
	}

	if cfg.Host == nil {
		cfg.Host = DefaultHostOption
	}

	return nil
}

// NewPeerstore creates a threadsafe collection of peers.
func NewPeerstore() Peerstore {
	return &peerstore{
		keybook:     *newKeybook(),
		metrics:     *(NewMetrics()).(*metrics),
		AddrManager: AddrManager{},
		ds:          dssync.MutexWrap(ds.NewMapDatastore()),
	}
}

func (pn *peernet) Adapter(p testutil.Identity) bsnet.BitSwapNetwork {
	client, err := pn.Mocknet.AddPeer(p.PrivateKey(), p.Address())
	if err != nil {
		panic(err.Error())
	}
	routing := pn.routingserver.ClientWithDatastore(context.TODO(), p, ds.NewMapDatastore())
	return bsnet.NewFromIpfsHost(client, routing)
}

func TestReturnsErrorWhenSizeNegative(t *testing.T) {
	bs := NewBlockstore(syncds.MutexWrap(ds.NewMapDatastore()))
	_, err := WriteCached(bs, -1)
	if err != nil {
		return
	}
	t.Fail()
}

func newEngine(ctx context.Context, idStr string) peerAndEngine {
	return peerAndEngine{
		Peer: peer.ID(idStr),
		//Strategy: New(true),
		Engine: NewEngine(ctx,
			blockstore.NewBlockstore(dssync.MutexWrap(ds.NewMapDatastore()))),
	}
}

func getMockDagServAndBstore(t testing.TB) (mdag.DAGService, blockstore.Blockstore, pin.ManualPinner) {
	dstore := ds.NewMapDatastore()
	tsds := sync.MutexWrap(dstore)
	bstore := blockstore.NewBlockstore(tsds)
	bserv := bs.New(bstore, offline.Exchange(bstore))
	dserv := mdag.NewDAGService(bserv)
	return dserv, bstore, pin.NewPinner(tsds, dserv).GetManual()
}

func TestGetWhenKeyNotPresent(t *testing.T) {
	bs := NewBlockstore(ds_sync.MutexWrap(ds.NewMapDatastore()))
	_, err := bs.Get(key.Key("not present"))

	if err != nil {
		t.Log("As expected, block is not present")
		return
	}
	t.Fail()
}

func getDagservAndPinner(t *testing.T) dagservAndPinner {
	db := dssync.MutexWrap(ds.NewMapDatastore())
	bs := bstore.NewBlockstore(db)
	blockserv := bserv.New(bs, offline.Exchange(bs))
	dserv := NewDAGService(blockserv)
	mpin := pin.NewPinner(db, dserv).GetManual()
	return dagservAndPinner{
		ds: dserv,
		mp: mpin,
	}
}

func (ks *DSSuite) TestBasic(c *C) {

	mpds := ds.NewMapDatastore()
	nsds := ns.Wrap(mpds, ds.NewKey("abc"))

	keys := strsToKeys([]string{
		"foo",
		"foo/bar",
		"foo/bar/baz",
		"foo/barb",
		"foo/bar/bazb",
		"foo/bar/baz/barb",
	})

	for _, k := range keys {
		err := nsds.Put(k, []byte(k.String()))
		c.Check(err, Equals, nil)
	}

	for _, k := range keys {
		v1, err := nsds.Get(k)
		c.Check(err, Equals, nil)
		c.Check(bytes.Equal(v1.([]byte), []byte(k.String())), Equals, true)

		v2, err := mpds.Get(ds.NewKey("abc").Child(k))
		c.Check(err, Equals, nil)
		c.Check(bytes.Equal(v2.([]byte), []byte(k.String())), Equals, true)
	}

	run := func(d ds.Datastore, q dsq.Query) []ds.Key {
		r, err := d.Query(q)
		c.Check(err, Equals, nil)

		e, err := r.Rest()
		c.Check(err, Equals, nil)

		return ds.EntryKeys(e)
	}

	listA := run(mpds, dsq.Query{})
	listB := run(nsds, dsq.Query{})
	c.Check(len(listA), Equals, len(listB))

	// sort them cause yeah.
	sort.Sort(ds.KeySlice(listA))
	sort.Sort(ds.KeySlice(listB))

	for i, kA := range listA {
		kB := listB[i]
		c.Check(nsds.InvertKey(kA), Equals, kB)
		c.Check(kA, Equals, nsds.ConvertKey(kB))
	}
}

func setupDHT(ctx context.Context, t *testing.T) *IpfsDHT {
	h := netutil.GenHostSwarm(t, ctx)

	dss := dssync.MutexWrap(ds.NewMapDatastore())
	d := NewDHT(ctx, h, dss)

	d.Validator["v"] = &record.ValidChecker{
		Func: func(key.Key, []byte) error {
			return nil
		},
		Sign: false,
	}
	return d
}

func TestValueTypeMismatch(t *testing.T) {
	block := blocks.NewBlock([]byte("some data"))

	datastore := ds.NewMapDatastore()
	k := BlockPrefix.Child(block.Key().DsKey())
	datastore.Put(k, "data that isn't a block!")

	blockstore := NewBlockstore(ds_sync.MutexWrap(datastore))

	_, err := blockstore.Get(block.Key())
	if err != ValueTypeMismatch {
		t.Fatal(err)
	}
}

func TestTiered(t *testing.T) {
	d1 := ds.NewMapDatastore()
	d2 := ds.NewMapDatastore()
	d3 := ds.NewMapDatastore()
	d4 := ds.NewMapDatastore()

	td := New(d1, d2, d3, d4)
	td.Put(ds.NewKey("foo"), "bar")
	testHas(t, []ds.Datastore{td}, ds.NewKey("foo"), "bar")
	testHas(t, td, ds.NewKey("foo"), "bar") // all children

	// remove it from, say, caches.
	d1.Delete(ds.NewKey("foo"))
	d2.Delete(ds.NewKey("foo"))
	testHas(t, []ds.Datastore{td}, ds.NewKey("foo"), "bar")
	testHas(t, td[2:], ds.NewKey("foo"), "bar")
	testNotHas(t, td[:2], ds.NewKey("foo"))

	// write it again.
	td.Put(ds.NewKey("foo"), "bar2")
	testHas(t, []ds.Datastore{td}, ds.NewKey("foo"), "bar2")
	testHas(t, td, ds.NewKey("foo"), "bar2")
}

func TestElideDuplicateWrite(t *testing.T) {
	cd := &callbackDatastore{f: func() {}, ds: ds.NewMapDatastore()}
	bs := NewBlockstore(syncds.MutexWrap(cd))
	cachedbs, err := WriteCached(bs, 1)
	if err != nil {
		t.Fatal(err)
	}

	b1 := blocks.NewBlock([]byte("foo"))

	cachedbs.Put(b1)
	cd.SetFunc(func() {
		t.Fatal("write hit the datastore")
	})
	cachedbs.Put(b1)
}

func TestOutboxClosedWhenEngineClosed(t *testing.T) {
	t.SkipNow() // TODO implement *Engine.Close
	e := NewEngine(context.Background(), blockstore.NewBlockstore(dssync.MutexWrap(ds.NewMapDatastore())))
	var wg sync.WaitGroup
	wg.Add(1)
	go func() {
		for nextEnvelope := range e.Outbox() {
			<-nextEnvelope
		}
		wg.Done()
	}()
	// e.Close()
	wg.Wait()
	if _, ok := <-e.Outbox(); ok {
		t.Fatal("channel should be closed")
	}
}

func newBlockStoreWithKeys(t *testing.T, d ds.Datastore, N int) (Blockstore, []key.Key) {
	if d == nil {
		d = ds.NewMapDatastore()
	}
	bs := NewBlockstore(ds_sync.MutexWrap(d))

	keys := make([]key.Key, N)
	for i := 0; i < N; i++ {
		block := blocks.NewBlock([]byte(fmt.Sprintf("some data %d", i)))
		err := bs.Put(block)
		if err != nil {
			t.Fatal(err)
		}
		keys[i] = block.Key()
	}
	return bs, keys
}

func TestPutThenGetBlock(t *testing.T) {
	bs := NewBlockstore(ds_sync.MutexWrap(ds.NewMapDatastore()))
	block := blocks.NewBlock([]byte("some data"))

	err := bs.Put(block)
	if err != nil {
		t.Fatal(err)
	}

	blockFromBlockstore, err := bs.Get(block.Key())
	if err != nil {
		t.Fatal(err)
	}
	if !bytes.Equal(block.Data, blockFromBlockstore.Data) {
		t.Fail()
	}
}

func TestPartnerWantsThenCancels(t *testing.T) {
	numRounds := 10
	if testing.Short() {
		numRounds = 1
	}
	alphabet := strings.Split("abcdefghijklmnopqrstuvwxyz", "")
	vowels := strings.Split("aeiou", "")

	type testCase [][]string
	testcases := []testCase{
		{
			alphabet, vowels,
		},
		{
			alphabet, stringsComplement(alphabet, vowels),
		},
	}

	bs := blockstore.NewBlockstore(dssync.MutexWrap(ds.NewMapDatastore()))
	for _, letter := range alphabet {
		block := blocks.NewBlock([]byte(letter))
		if err := bs.Put(block); err != nil {
			t.Fatal(err)
		}
	}

	for i := 0; i < numRounds; i++ {
		for _, testcase := range testcases {
			set := testcase[0]
			cancels := testcase[1]
			keeps := stringsComplement(set, cancels)

			e := NewEngine(context.Background(), bs)
			partner := testutil.RandPeerIDFatal(t)

			partnerWants(e, set, partner)
			partnerCancels(e, cancels, partner)
			if err := checkHandledInOrder(t, e, keeps); err != nil {
				t.Logf("run #%d of %d", i, numRounds)
				t.Fatal(err)
			}
		}
	}
}