package coordinator_test

import (
	"context"
	"github.com/influxdata/influx-cli/v2/api"
	"reflect"
	"testing"
	"time"

	"github.com/golang/mock/gomock"
	"github.com/influxdata/influxdb/v2"
	"github.com/influxdata/influxdb/v2/dbrp/mocks"
	"github.com/influxdata/influxdb/v2/influxql/query"
	"github.com/influxdata/influxdb/v2/internal"
	"github.com/influxdata/influxdb/v2/kit/platform"
	"github.com/influxdata/influxdb/v2/tsdb"
	"github.com/influxdata/influxdb/v2/v1/coordinator"
	"github.com/influxdata/influxdb/v2/v1/services/meta"
	"github.com/influxdata/influxql"
)

func TestLocalShardMapper(t *testing.T) {
	orgID := platform.ID(0xff00)
	bucketID := platform.ID(0xffee)

	tests := []struct {
		name    string
		db      string
		rp      string
		filt    influxdb.DBRPMappingFilter
		mapping []*influxdb.DBRPMapping
	}{
		{
			name:    "Physical DBRP Mapping",
			db:      "db0",
			rp:      "rp0",
			filt:    influxdb.DBRPMappingFilter{OrgID: &orgID, Database: api.PtrString("db0"), RetentionPolicy: api.PtrString("rp0"), Virtual: nil},
			mapping: []*influxdb.DBRPMapping{{Database: "db0", RetentionPolicy: "rp0", OrganizationID: orgID, BucketID: bucketID}},
		},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			ctrl := gomock.NewController(t)
			defer ctrl.Finish()

			dbrp := mocks.NewMockDBRPMappingService(ctrl)
			dbrp.EXPECT().
				FindMany(gomock.Any(), tc.filt).
				Times(2).
				Return(tc.mapping, len(tc.mapping), nil)

			var metaClient MetaClient
			metaClient.ShardGroupsByTimeRangeFn = func(database, policy string, min, max time.Time) ([]meta.ShardGroupInfo, error) {
				if database != bucketID.String() {
					t.Errorf("unexpected database: %s", database)
				}
				if policy != meta.DefaultRetentionPolicyName {
					t.Errorf("unexpected retention policy: %s", policy)
				}
				return []meta.ShardGroupInfo{
					{ID: 1, Shards: []meta.ShardInfo{
						{ID: 1, Owners: []meta.ShardOwner{{NodeID: 0}}},
						{ID: 2, Owners: []meta.ShardOwner{{NodeID: 0}}},
					}},
					{ID: 2, Shards: []meta.ShardInfo{
						{ID: 3, Owners: []meta.ShardOwner{{NodeID: 0}}},
						{ID: 4, Owners: []meta.ShardOwner{{NodeID: 0}}},
					}},
				}, nil
			}

			tsdbStore := &internal.TSDBStoreMock{}
			tsdbStore.ShardGroupFn = func(ids []uint64) tsdb.ShardGroup {
				if !reflect.DeepEqual(ids, []uint64{1, 2, 3, 4}) {
					t.Errorf("unexpected shard ids: %#v", ids)
				}

				var sh MockShard
				sh.CreateIteratorFn = func(ctx context.Context, measurement *influxql.Measurement, opt query.IteratorOptions) (query.Iterator, error) {
					if measurement.Name != "cpu" {
						t.Errorf("unexpected measurement: %s", measurement.Name)
					}
					return &FloatIterator{}, nil
				}
				return &sh
			}

			// Initialize the shard mapper.
			shardMapper := &coordinator.LocalShardMapper{
				MetaClient: &metaClient,
				TSDBStore:  tsdbStore,
				DBRP:       dbrp,
			}

			// Normal measurement.
			measurement := &influxql.Measurement{
				Database:        tc.db,
				RetentionPolicy: tc.rp,
				Name:            "cpu",
			}
			ic, err := shardMapper.MapShards(context.Background(), []influxql.Source{measurement}, influxql.TimeRange{}, query.SelectOptions{OrgID: orgID})
			if err != nil {
				t.Fatalf("unexpected error: %s", err)
			}

			// This should be a LocalShardMapping.
			m, ok := ic.(*coordinator.LocalShardMapping)
			if !ok {
				t.Fatalf("unexpected mapping type: %T", ic)
			} else if len(m.ShardMap) != 1 {
				t.Fatalf("unexpected number of shard mappings: %d", len(m.ShardMap))
			}

			if _, err := ic.CreateIterator(context.Background(), measurement, query.IteratorOptions{OrgID: orgID}); err != nil {
				t.Fatalf("unexpected error: %s", err)
			}

			// Subquery.
			subquery := &influxql.SubQuery{
				Statement: &influxql.SelectStatement{
					Sources: []influxql.Source{measurement},
				},
			}
			ic, err = shardMapper.MapShards(context.Background(), []influxql.Source{subquery}, influxql.TimeRange{}, query.SelectOptions{OrgID: orgID})
			if err != nil {
				t.Fatalf("unexpected error: %s", err)
			}

			// This should be a LocalShardMapping.
			m, ok = ic.(*coordinator.LocalShardMapping)
			if !ok {
				t.Fatalf("unexpected mapping type: %T", ic)
			} else if len(m.ShardMap) != 1 {
				t.Fatalf("unexpected number of shard mappings: %d", len(m.ShardMap))
			}

			if _, err := ic.CreateIterator(context.Background(), measurement, query.IteratorOptions{OrgID: orgID}); err != nil {
				t.Fatalf("unexpected error: %s", err)
			}
		})
	}
}