package sqleng

import (
	"fmt"
	"net"
	"testing"
	"time"

	"github.com/grafana/grafana-plugin-sdk-go/backend"
	"github.com/grafana/grafana-plugin-sdk-go/data"
	"github.com/grafana/grafana-plugin-sdk-go/data/sqlutil"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/grafana/grafana/pkg/infra/log"
	"github.com/grafana/grafana/pkg/tsdb/sqleng/util"
)

func TestSQLEngine(t *testing.T) {
	dt := time.Date(2018, 3, 14, 21, 20, 6, int(527345*time.Microsecond), time.UTC)

	t.Run("Given a time range between 2018-04-12 00:00 and 2018-04-12 00:05", func(t *testing.T) {
		from := time.Date(2018, 4, 12, 18, 0, 0, 0, time.UTC)
		to := from.Add(5 * time.Minute)
		timeRange := backend.TimeRange{From: from, To: to}
		query := backend.DataQuery{JSON: []byte("{}")}

		t.Run("interpolate $__interval", func(t *testing.T) {
			sql, err := Interpolate(query, timeRange, "", "select $__interval ")
			require.NoError(t, err)
			require.Equal(t, "select 1m ", sql)
		})

		t.Run("interpolate $__interval in $__timeGroup", func(t *testing.T) {
			sql, err := Interpolate(query, timeRange, "", "select $__timeGroupAlias(time,$__interval)")
			require.NoError(t, err)
			require.Equal(t, "select $__timeGroupAlias(time,1m)", sql)
		})

		t.Run("interpolate $__interval_ms", func(t *testing.T) {
			sql, err := Interpolate(query, timeRange, "", "select $__interval_ms ")
			require.NoError(t, err)
			require.Equal(t, "select 60000 ", sql)
		})

		t.Run("interpolate __unixEpochFrom function", func(t *testing.T) {
			sql, err := Interpolate(query, timeRange, "", "select $__unixEpochFrom()")
			require.NoError(t, err)
			require.Equal(t, fmt.Sprintf("select %d", from.Unix()), sql)
		})

		t.Run("interpolate __unixEpochTo function", func(t *testing.T) {
			sql, err := Interpolate(query, timeRange, "", "select $__unixEpochTo()")
			require.NoError(t, err)
			require.Equal(t, fmt.Sprintf("select %d", to.Unix()), sql)
		})
	})

	t.Run("Given row values with int64 as time columns", func(t *testing.T) {
		tSeconds := dt.Unix()
		tMilliseconds := dt.UnixNano() / 1e6
		tNanoSeconds := dt.UnixNano()
		var nilPointer *int64

		originFrame := data.NewFrame("",
			data.NewField("time1", nil, []int64{
				tSeconds,
			}),
			data.NewField("time2", nil, []*int64{
				util.Pointer(tSeconds),
			}),
			data.NewField("time3", nil, []int64{
				tMilliseconds,
			}),
			data.NewField("time4", nil, []*int64{
				util.Pointer(tMilliseconds),
			}),
			data.NewField("time5", nil, []int64{
				tNanoSeconds,
			}),
			data.NewField("time6", nil, []*int64{
				util.Pointer(tNanoSeconds),
			}),
			data.NewField("time7", nil, []*int64{
				nilPointer,
			}),
		)

		for i := 0; i < len(originFrame.Fields); i++ {
			err := convertSQLTimeColumnToEpochMS(originFrame, i)
			require.NoError(t, err)
		}

		require.Equal(t, dt.Unix(), (*originFrame.Fields[0].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[1].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[2].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[3].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[4].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[5].At(0).(*time.Time)).Unix())
		require.Nil(t, originFrame.Fields[6].At(0))
	})

	t.Run("Given row values with uint64 as time columns", func(t *testing.T) {
		tSeconds := uint64(dt.Unix())
		tMilliseconds := uint64(dt.UnixNano() / 1e6)
		tNanoSeconds := uint64(dt.UnixNano())
		var nilPointer *uint64

		originFrame := data.NewFrame("",
			data.NewField("time1", nil, []uint64{
				tSeconds,
			}),
			data.NewField("time2", nil, []*uint64{
				util.Pointer(tSeconds),
			}),
			data.NewField("time3", nil, []uint64{
				tMilliseconds,
			}),
			data.NewField("time4", nil, []*uint64{
				util.Pointer(tMilliseconds),
			}),
			data.NewField("time5", nil, []uint64{
				tNanoSeconds,
			}),
			data.NewField("time6", nil, []*uint64{
				util.Pointer(tNanoSeconds),
			}),
			data.NewField("time7", nil, []*uint64{
				nilPointer,
			}),
		)

		for i := 0; i < len(originFrame.Fields); i++ {
			err := convertSQLTimeColumnToEpochMS(originFrame, i)
			require.NoError(t, err)
		}

		require.Equal(t, dt.Unix(), (*originFrame.Fields[0].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[1].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[2].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[3].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[4].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[5].At(0).(*time.Time)).Unix())
		require.Nil(t, originFrame.Fields[6].At(0))
	})

	t.Run("Given row values with int32 as time columns", func(t *testing.T) {
		tSeconds := int32(dt.Unix())
		var nilInt *int32

		originFrame := data.NewFrame("",
			data.NewField("time1", nil, []int32{
				tSeconds,
			}),
			data.NewField("time2", nil, []*int32{
				util.Pointer(tSeconds),
			}),
			data.NewField("time7", nil, []*int32{
				nilInt,
			}),
		)
		for i := 0; i < 3; i++ {
			err := convertSQLTimeColumnToEpochMS(originFrame, i)
			require.NoError(t, err)
		}

		require.Equal(t, dt.Unix(), (*originFrame.Fields[0].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[1].At(0).(*time.Time)).Unix())
		require.Nil(t, originFrame.Fields[2].At(0))
	})

	t.Run("Given row values with uint32 as time columns", func(t *testing.T) {
		tSeconds := uint32(dt.Unix())
		var nilInt *uint32

		originFrame := data.NewFrame("",
			data.NewField("time1", nil, []uint32{
				tSeconds,
			}),
			data.NewField("time2", nil, []*uint32{
				util.Pointer(tSeconds),
			}),
			data.NewField("time7", nil, []*uint32{
				nilInt,
			}),
		)
		for i := 0; i < len(originFrame.Fields); i++ {
			err := convertSQLTimeColumnToEpochMS(originFrame, i)
			require.NoError(t, err)
		}
		require.Equal(t, dt.Unix(), (*originFrame.Fields[0].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[1].At(0).(*time.Time)).Unix())
		require.Nil(t, originFrame.Fields[2].At(0))
	})

	t.Run("Given row values with float64 as time columns", func(t *testing.T) {
		tSeconds := float64(dt.UnixNano()) / float64(time.Second)
		tMilliseconds := float64(dt.UnixNano()) / float64(time.Millisecond)
		tNanoSeconds := float64(dt.UnixNano())
		var nilPointer *float64

		originFrame := data.NewFrame("",
			data.NewField("time1", nil, []float64{
				tSeconds,
			}),
			data.NewField("time2", nil, []*float64{
				util.Pointer(tSeconds),
			}),
			data.NewField("time3", nil, []float64{
				tMilliseconds,
			}),
			data.NewField("time4", nil, []*float64{
				util.Pointer(tMilliseconds),
			}),
			data.NewField("time5", nil, []float64{
				tNanoSeconds,
			}),
			data.NewField("time6", nil, []*float64{
				util.Pointer(tNanoSeconds),
			}),
			data.NewField("time7", nil, []*float64{
				nilPointer,
			}),
		)

		for i := 0; i < len(originFrame.Fields); i++ {
			err := convertSQLTimeColumnToEpochMS(originFrame, i)
			require.NoError(t, err)
		}

		require.Equal(t, dt.Unix(), (*originFrame.Fields[0].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[1].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[2].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[3].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[4].At(0).(*time.Time)).Unix())
		require.Equal(t, dt.Unix(), (*originFrame.Fields[5].At(0).(*time.Time)).Unix())
		require.Nil(t, originFrame.Fields[6].At(0))
	})

	t.Run("Given row values with float32 as time columns", func(t *testing.T) {
		tSeconds := float32(dt.Unix())
		var nilInt *float32

		originFrame := data.NewFrame("",
			data.NewField("time1", nil, []float32{
				tSeconds,
			}),
			data.NewField("time2", nil, []*float32{
				util.Pointer(tSeconds),
			}),
			data.NewField("time7", nil, []*float32{
				nilInt,
			}),
		)
		for i := 0; i < len(originFrame.Fields); i++ {
			err := convertSQLTimeColumnToEpochMS(originFrame, i)
			require.NoError(t, err)
		}
		require.Equal(t, int64(tSeconds), (*originFrame.Fields[0].At(0).(*time.Time)).Unix())
		require.Equal(t, int64(tSeconds), (*originFrame.Fields[1].At(0).(*time.Time)).Unix())
		require.Nil(t, originFrame.Fields[2].At(0))
	})

	t.Run("Given row with value columns, would be converted to float64", func(t *testing.T) {
		originFrame := data.NewFrame("",
			data.NewField("value1", nil, []int64{
				int64(1),
			}),
			data.NewField("value2", nil, []*int64{
				util.Pointer(int64(1)),
			}),
			data.NewField("value3", nil, []int32{
				int32(1),
			}),
			data.NewField("value4", nil, []*int32{
				util.Pointer(int32(1)),
			}),
			data.NewField("value5", nil, []int16{
				int16(1),
			}),
			data.NewField("value6", nil, []*int16{
				util.Pointer(int16(1)),
			}),
			data.NewField("value7", nil, []int8{
				int8(1),
			}),
			data.NewField("value8", nil, []*int8{
				util.Pointer(int8(1)),
			}),
			data.NewField("value9", nil, []float64{
				float64(1),
			}),
			data.NewField("value10", nil, []*float64{
				util.Pointer(1.0),
			}),
			data.NewField("value11", nil, []float32{
				float32(1),
			}),
			data.NewField("value12", nil, []*float32{
				util.Pointer(float32(1)),
			}),
			data.NewField("value13", nil, []uint64{
				uint64(1),
			}),
			data.NewField("value14", nil, []*uint64{
				util.Pointer(uint64(1)),
			}),
			data.NewField("value15", nil, []uint32{
				uint32(1),
			}),
			data.NewField("value16", nil, []*uint32{
				util.Pointer(uint32(1)),
			}),
			data.NewField("value17", nil, []uint16{
				uint16(1),
			}),
			data.NewField("value18", nil, []*uint16{
				util.Pointer(uint16(1)),
			}),
			data.NewField("value19", nil, []uint8{
				uint8(1),
			}),
			data.NewField("value20", nil, []*uint8{
				util.Pointer(uint8(1)),
			}),
		)
		for i := 0; i < len(originFrame.Fields); i++ {
			_, err := convertSQLValueColumnToFloat(originFrame, i)
			require.NoError(t, err)
			if i == 8 {
				require.Equal(t, float64(1), originFrame.Fields[i].At(0).(float64))
			} else {
				require.NotNil(t, originFrame.Fields[i].At(0).(*float64))
				require.Equal(t, float64(1), *originFrame.Fields[i].At(0).(*float64))
			}
		}
	})

	t.Run("Given row with nil value columns", func(t *testing.T) {
		var int64NilPointer *int64
		var int32NilPointer *int32
		var int16NilPointer *int16
		var int8NilPointer *int8
		var float64NilPointer *float64
		var float32NilPointer *float32
		var uint64NilPointer *uint64
		var uint32NilPointer *uint32
		var uint16NilPointer *uint16
		var uint8NilPointer *uint8

		originFrame := data.NewFrame("",
			data.NewField("value1", nil, []*int64{
				int64NilPointer,
			}),
			data.NewField("value2", nil, []*int32{
				int32NilPointer,
			}),
			data.NewField("value3", nil, []*int16{
				int16NilPointer,
			}),
			data.NewField("value4", nil, []*int8{
				int8NilPointer,
			}),
			data.NewField("value5", nil, []*float64{
				float64NilPointer,
			}),
			data.NewField("value6", nil, []*float32{
				float32NilPointer,
			}),
			data.NewField("value7", nil, []*uint64{
				uint64NilPointer,
			}),
			data.NewField("value8", nil, []*uint32{
				uint32NilPointer,
			}),
			data.NewField("value9", nil, []*uint16{
				uint16NilPointer,
			}),
			data.NewField("value10", nil, []*uint8{
				uint8NilPointer,
			}),
		)
		for i := 0; i < len(originFrame.Fields); i++ {
			t.Run("", func(t *testing.T) {
				_, err := convertSQLValueColumnToFloat(originFrame, i)
				require.NoError(t, err)
				require.Nil(t, originFrame.Fields[i].At(0))
			})
		}
	})

	t.Run("Should handle connection errors", func(t *testing.T) {
		randomErr := fmt.Errorf("random error")

		tests := []struct {
			err                                   error
			expectedErr                           error
			expectQueryResultTransformerWasCalled bool
		}{
			{err: &net.OpError{Op: "Dial"}, expectedErr: ErrConnectionFailed, expectQueryResultTransformerWasCalled: false},
			{err: randomErr, expectedErr: randomErr, expectQueryResultTransformerWasCalled: true},
		}

		for _, tc := range tests {
			transformer := &testQueryResultTransformer{}
			dp := DataSourceHandler{
				log:                    log.New("test"),
				queryResultTransformer: transformer,
			}
			resultErr := dp.TransformQueryError(dp.log, tc.err)
			assert.ErrorIs(t, resultErr, tc.expectedErr)
			assert.Equal(t, tc.expectQueryResultTransformerWasCalled, transformer.transformQueryErrorWasCalled)
		}
	})
}

type testQueryResultTransformer struct {
	transformQueryErrorWasCalled bool
}

func (t *testQueryResultTransformer) TransformQueryError(_ log.Logger, err error) error {
	t.transformQueryErrorWasCalled = true
	return err
}

func (t *testQueryResultTransformer) GetConverterList() []sqlutil.StringConverter {
	return nil
}