// FilterUids filters the uids based on the corresponding values and QueryData.
func FilterUids(uids *task.List, values []*task.Value, q *QueryData) *task.List {
	x.AssertTruef(len(values) == len(uids.Uids), "lengths not matching")
	rv := &task.List{}
	for i := 0; i < len(values); i++ {
		valBytes := values[i].Val
		if bytes.Equal(valBytes, nil) {
			continue
		}
		vType := values[i].ValType
		if types.TypeID(vType) != types.GeoID {
			continue
		}
		var g types.Geo
		if err := g.UnmarshalBinary(valBytes); err != nil {
			continue
		}

		if !q.MatchesFilter(g) {
			continue
		}

		// we matched the geo filter, add the uid to the list
		rv.Uids = append(rv.Uids, uids.Uids[i])
	}
	return rv
}

func addGeoData(t *testing.T, ps *store.Store, uid uint64, p geom.T, name string) {
	g := types.Geo{p}
	value, err := g.MarshalBinary()
	require.NoError(t, err)
	addEdgeToTypedValue(t, ps, "geometry", uid, types.GeoID, value)
	addEdgeToTypedValue(t, ps, "name", uid, types.StringID, []byte(name))
}

func formDataPolygon(t *testing.T, p *geom.Polygon) string {
	d, err := wkb.Marshal(p, binary.LittleEndian)
	require.NoError(t, err)
	var g types.Geo
	require.NoError(t, g.UnmarshalBinary(d))
	gb, err := g.MarshalText()
	require.NoError(t, err)
	return string(gb)
}

func formData(t *testing.T, str string) string {
	p, err := loadPolygon(str)
	require.NoError(t, err)

	d, err := wkb.Marshal(p, binary.LittleEndian)
	require.NoError(t, err)
	var g types.Geo
	require.NoError(t, g.UnmarshalBinary(d))
	gb, err := g.MarshalText()
	require.NoError(t, err)
	return string(gb)
}

func BenchmarkKeyGeneratorPoint(b *testing.B) {
	p := geom.NewPoint(geom.XY).MustSetCoords(geom.Coord{-122.082506, 37.4249518})
	data, err := wkb.Marshal(p, binary.LittleEndian)
	if err != nil {
		b.Error(err)
	}
	var g types.Geo
	g.UnmarshalBinary(data)
	b.ResetTimer()
	for n := 0; n < b.N; n++ {
		IndexTokens(&g)
	}
}

func TestKeyGeneratorPolygon(t *testing.T) {
	p, err := loadPolygon("zip.json")
	require.NoError(t, err)
	data, err := wkb.Marshal(p, binary.LittleEndian)
	require.NoError(t, err)

	var g types.Geo
	err = g.UnmarshalBinary(data)
	require.NoError(t, err)
	keys, err := IndexTokens(&g)
	require.NoError(t, err)
	require.Len(t, keys, 65)
}

func TestKeyGeneratorPoint(t *testing.T) {
	p := geom.NewPoint(geom.XY).MustSetCoords(geom.Coord{-122.082506, 37.4249518})
	data, err := wkb.Marshal(p, binary.LittleEndian)
	require.NoError(t, err)

	var g types.Geo
	err = g.UnmarshalBinary(data)
	require.NoError(t, err)

	keys, err := IndexTokens(&g)
	require.NoError(t, err)
	require.Len(t, keys, MaxCellLevel-MinCellLevel+1+1) // +1 for the cover
}

func BenchmarkKeyGeneratorPolygon(b *testing.B) {
	p, err := loadPolygon("zip.json")
	if err != nil {
		b.Error(err)
	}
	data, err := wkb.Marshal(p, binary.LittleEndian)
	if err != nil {
		b.Error(err)
	}
	var g types.Geo
	g.UnmarshalBinary(data)
	b.ResetTimer()
	for n := 0; n < b.N; n++ {
		IndexTokens(&g)
	}
}

// IndexCells returns two cellunions. The first is a list of parents, which are all the cells upto
// the min level that contain this geometry. The second is the cover, which are the smallest
// possible cells required to cover the region. This makes it easier at query time to query only the
// parents or only the cover or both depending on whether it is a within, contains or intersects
// query.
func indexCells(g types.Geo) (parents, cover s2.CellUnion, err error) {
	if g.Stride() != 2 {
		return nil, nil, x.Errorf("Covering only available for 2D co-ordinates.")
	}
	switch v := g.T.(type) {
	case *geom.Point:
		p, c := indexCellsForPoint(v, MinCellLevel, MaxCellLevel)
		return p, c, nil
	case *geom.Polygon:
		l, err := loopFromPolygon(v)
		if err != nil {
			return nil, nil, err
		}
		cover := coverLoop(l, MinCellLevel, MaxCellLevel, MaxCells)
		parents := getParentCells(cover, MinCellLevel)
		return parents, cover, nil
	default:
		return nil, nil, x.Errorf("Cannot index geometry of type %T", v)
	}
}

func typeValueFromNQuad(nq *graph.NQuad) (types.Value, error) {
	if nq.Value == nil || nq.Value.Val == nil {
		return nil, nil
	}
	switch v := nq.Value.Val.(type) {
	case *graph.Value_BytesVal:
		b := types.Bytes(v.BytesVal)
		return &b, nil
	case *graph.Value_IntVal:
		i := types.Int32(v.IntVal)
		return &i, nil
	case *graph.Value_StrVal:
		s := types.String(v.StrVal)
		return &s, nil
	case *graph.Value_BoolVal:
		b := types.Bool(v.BoolVal)
		return &b, nil
	case *graph.Value_DoubleVal:
		f := types.Float(v.DoubleVal)
		return &f, nil
	case *graph.Value_GeoVal:
		var geom types.Geo
		err := geom.UnmarshalBinary(v.GeoVal)
		if err != nil {
			return nil, err
		}
		return &geom, nil

	case nil:
		log.Fatalf("Val being nil is already handled")
		return nil, nil
	default:
		// Unknown type
		return nil, x.Errorf("Unknown value type %T", v)
	}
}

func populateGraph(t *testing.T) (string, string, *store.Store) {
	// logrus.SetLevel(logrus.DebugLevel)
	dir, err := ioutil.TempDir("", "storetest_")
	require.NoError(t, err)

	ps, err := store.NewStore(dir)
	require.NoError(t, err)

	schema.ParseBytes([]byte(schemaStr))
	posting.Init(ps)
	worker.Init(ps)

	group.ParseGroupConfig("")
	dir2, err := ioutil.TempDir("", "wal_")
	require.NoError(t, err)
	worker.StartRaftNodes(dir2)

	// So, user we're interested in has uid: 1.
	// She has 5 friends: 23, 24, 25, 31, and 101
	addEdgeToUID(t, ps, "friend", 1, 23)
	addEdgeToUID(t, ps, "friend", 1, 24)
	addEdgeToUID(t, ps, "friend", 1, 25)
	addEdgeToUID(t, ps, "friend", 1, 31)
	addEdgeToUID(t, ps, "friend", 1, 101)

	// Now let's add a few properties for the main user.
	addEdgeToValue(t, ps, "name", 1, "Michonne")
	addEdgeToValue(t, ps, "gender", 1, "female")
	var coord types.Geo
	err = coord.UnmarshalText([]byte("{\"Type\":\"Point\", \"Coordinates\":[1.1,2.0]}"))
	require.NoError(t, err)
	gData, err := coord.MarshalBinary()
	require.NoError(t, err)
	addEdgeToTypedValue(t, ps, "loc", 1, types.GeoID, gData)
	data, err := types.Int32(15).MarshalBinary()
	require.NoError(t, err)

	addEdgeToTypedValue(t, ps, "age", 1, types.Int32ID, data)
	addEdgeToValue(t, ps, "address", 1, "31, 32 street, Jupiter")
	data, err = types.Bool(true).MarshalBinary()
	require.NoError(t, err)
	addEdgeToTypedValue(t, ps, "alive", 1, types.BoolID, data)
	addEdgeToValue(t, ps, "age", 1, "38")
	addEdgeToValue(t, ps, "survival_rate", 1, "98.99")
	addEdgeToValue(t, ps, "sword_present", 1, "true")
	addEdgeToValue(t, ps, "_xid_", 1, "mich")

	// Now let's add a name for each of the friends, except 101.
	addEdgeToTypedValue(t, ps, "name", 23, types.StringID, []byte("Rick Grimes"))
	addEdgeToValue(t, ps, "age", 23, "15")

	err = coord.UnmarshalText([]byte(`{"Type":"Polygon", "Coordinates":[[[0.0,0.0], [2.0,0.0], [2.0, 2.0], [0.0, 2.0]]]}`))
	require.NoError(t, err)
	gData, err = coord.MarshalBinary()
	require.NoError(t, err)
	addEdgeToTypedValue(t, ps, "loc", 23, types.GeoID, gData)

	addEdgeToValue(t, ps, "address", 23, "21, mark street, Mars")
	addEdgeToValue(t, ps, "name", 24, "Glenn Rhee")
	addEdgeToValue(t, ps, "name", 25, "Daryl Dixon")
	addEdgeToValue(t, ps, "name", 31, "Andrea")

	addEdgeToValue(t, ps, "dob", 23, "1910-01-02")
	addEdgeToValue(t, ps, "dob", 24, "1909-05-05")
	addEdgeToValue(t, ps, "dob", 25, "1909-01-10")
	addEdgeToValue(t, ps, "dob", 31, "1901-01-15")

	return dir, dir2, ps
}

func TestSchema(t *testing.T) {
	dir, dir2, _ := populateGraph(t)
	defer os.RemoveAll(dir)
	defer os.RemoveAll(dir2)

	query := `
		{
			debug(_uid_:0x1) {
				_xid_
				name
				gender
				alive
				loc
				friend {
					name
				}
				friend {
				}
			}
		}
  `

	gq, _, err := gql.Parse(query)
	require.NoError(t, err)

	ctx := context.Background()
	sg, err := ToSubGraph(ctx, gq)
	require.NoError(t, err)

	ch := make(chan error)
	go ProcessGraph(ctx, sg, nil, ch)
	err = <-ch
	require.NoError(t, err)

	var l Latency
	gr, err := sg.ToProtocolBuffer(&l)
	require.NoError(t, err)

	require.EqualValues(t, "debug", gr.Children[0].Attribute)
	require.EqualValues(t, 1, gr.Children[0].Uid)
	require.EqualValues(t, "mich", gr.Children[0].Xid)
	require.Len(t, gr.Children[0].Properties, 4)

	require.EqualValues(t, "Michonne",
		getProperty(gr.Children[0].Properties, "name").GetStrVal())
	var g types.Geo
	x.Check(g.UnmarshalBinary(getProperty(gr.Children[0].Properties, "loc").GetGeoVal()))
	received, err := g.MarshalText()
	require.EqualValues(t, "{'type':'Point','coordinates':[1.1,2]}", string(received))

	require.Len(t, gr.Children[0].Children, 5)

	child := gr.Children[0].Children[0]
	require.EqualValues(t, 23, child.Uid)
	require.EqualValues(t, "friend", child.Attribute)

	require.Len(t, child.Properties, 1)
	require.EqualValues(t, "Rick Grimes",
		getProperty(child.Properties, "name").GetStrVal())
	require.Empty(t, child.Children)

	child = gr.Children[0].Children[1]
	require.EqualValues(t, 24, child.Uid)
	require.EqualValues(t, "friend", child.Attribute)

	require.Len(t, child.Properties, 1)
	require.EqualValues(t, "Glenn Rhee",
		getProperty(child.Properties, "name").GetStrVal())
	require.Empty(t, child.Children)

	child = gr.Children[0].Children[4]
	require.EqualValues(t, 101, child.Uid)
	require.EqualValues(t, "friend", child.Attribute)

	require.Len(t, child.Properties, 0)
}

// queryTokens returns the tokens to be used to look up the geo index for a given filter.
func queryTokens(qt QueryType, data string, maxDistance float64) ([]string, *QueryData, error) {
	// Try to parse the data as geo type.
	var g types.Geo
	geoData := strings.Replace(data, "'", "\"", -1)
	err := g.UnmarshalText([]byte(geoData))
	if err != nil {
		return nil, nil, x.Wrapf(err, "Cannot decode given geoJson input")
	}

	var l *s2.Loop
	var pt *s2.Point
	switch v := g.T.(type) {
	case *geom.Point:
		p := pointFromPoint(v)
		pt = &p

	case *geom.Polygon:
		l, err = loopFromPolygon(v)
		if err != nil {
			return nil, nil, err
		}

	default:
		return nil, nil, x.Errorf("Cannot query using a geometry of type %T", v)
	}

	x.AssertTruef(l != nil || pt != nil, "We should have a point or a loop.")

	parents, cover, err := indexCells(g)
	if err != nil {
		return nil, nil, err
	}

	switch qt {
	case QueryTypeWithin:
		// For a within query we only need to look at the objects whose parents match our cover.
		// So we take our cover and prefix with the parentPrefix to look in the index.
		toks := toTokens(cover, parentPrefix)
		return toks, &QueryData{pt: pt, loop: l, qtype: qt}, nil

	case QueryTypeContains:
		if l != nil {
			return nil, nil, x.Errorf("Cannot use a polygon in a contains query")
		}
		// For a contains query, we only need to look at the objects whose cover matches our
		// parents. So we take our parents and prefix with the coverPrefix to look in the index.
		return toTokens(parents, coverPrefix), &QueryData{pt: pt, qtype: qt}, nil

	case QueryTypeNear:
		if l != nil {
			return nil, nil, x.Errorf("Cannot use a polygon in a near query")
		}
		return nearQueryKeys(*pt, maxDistance)

	case QueryTypeIntersects:
		// An intersects query is essentially the union of contains and within. So we look at all
		// the objects whose parents match our cover as well as all the objects whose cover matches
		// our parents.
		toks := parentCoverTokens(parents, cover)
		return toks, &QueryData{pt: pt, loop: l, qtype: qt}, nil

	default:
		return nil, nil, x.Errorf("Unknown query type")
	}
}