package main

import (
	"context"
	"testing"
	"time"

	"github.com/DATA-DOG/go-sqlmock"
	"lingniu-vehicle-ingest/go/vehicle-gateway/internal/envelope"
	"lingniu-vehicle-ingest/go/vehicle-gateway/internal/stats"
)

func TestChooseTrustedSourceKeepsContinuingSourceAndRejectsNewJump(t *testing.T) {
	previous := []dailySourceLast{{
		VIN:            "LA9GG64L7PBAF4001",
		SourceKey:      normalizedSourceKey("JT808", "13307765812", "", "115.231.168.135:42630"),
		Phone:          "13307765812",
		SourceEndpoint: "115.231.168.135:42630",
		TotalKM:        4100.8,
	}}
	current := []dailySourceLast{
		{
			VIN:            "LA9GG64L7PBAF4001",
			SourceKey:      normalizedSourceKey("JT808", "13307765812", "", "115.159.85.149:28316"),
			Phone:          "13307765812",
			SourceEndpoint: "115.159.85.149:28316",
			TotalKM:        42447.2,
		},
		{
			VIN:            "LA9GG64L7PBAF4001",
			SourceKey:      normalizedSourceKey("JT808", "13307765812", "", "115.231.168.135:20215"),
			Phone:          "13307765812",
			SourceEndpoint: "115.231.168.135:20215",
			TotalKM:        4123.9,
		},
	}

	chosen, ok := chooseTrustedSource(current, previous)
	if !ok {
		t.Fatal("chooseTrustedSource() did not choose a source")
	}
	if chosen.current.SourceKey != normalizedSourceKey("JT808", "13307765812", "", "115.231.168.135:20215") {
		t.Fatalf("chosen source = %q", chosen.current.SourceKey)
	}
	if delta := chosen.current.TotalKM - chosen.previous.TotalKM; delta < 23 || delta > 24 {
		t.Fatalf("delta = %v, want about 23.1", delta)
	}
}

func TestDailySourceLastBuildsCandidateKeysBySourceIP(t *testing.T) {
	sourceA := dailySourceLast{
		VIN:            "LA9GG64L7PBAF4001",
		SourceKey:      normalizedSourceKey("JT808", "13307765812", "", "115.231.168.135:20215"),
		Phone:          "13307765812",
		SourceEndpoint: "115.231.168.135:20215",
		TotalKM:        4123.9,
	}
	sourceB := dailySourceLast{
		VIN:            "LA9GG64L7PBAF4001",
		SourceKey:      normalizedSourceKey("JT808", "13307765812", "", "115.231.168.135:42630"),
		Phone:          "13307765812",
		SourceEndpoint: "115.231.168.135:42630",
		TotalKM:        4100.8,
	}
	if sourceA.SourceKey != sourceB.SourceKey {
		t.Fatalf("same source IP should produce same source key: %q vs %q", sourceA.SourceKey, sourceB.SourceKey)
	}
}

func TestAggregateFromDailySourceUsesOlderHistoricalBaseline(t *testing.T) {
	current := dailySourceLast{
		VIN:            "LMRKH9AC2R1004087",
		SourceKey:      normalizedSourceKey("YUTONG_MQTT", "", "LMRKH9AC2R1004087", "mqtt://yutong/ytforward/shln/3"),
		DeviceID:       "LMRKH9AC2R1004087",
		SourceEndpoint: "mqtt://yutong/ytforward/shln/3",
		FirstTS:        time.Date(2026, 7, 8, 8, 0, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600)),
		TS:             time.Date(2026, 7, 8, 17, 0, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600)),
		FirstTotalKM:   120778,
		TotalKM:        120788,
		RawSampleCount: 15,
	}
	previous := dailySourceLast{
		VIN:            "LMRKH9AC2R1004087",
		SourceKey:      current.SourceKey,
		DeviceID:       "LMRKH9AC2R1004087",
		SourceEndpoint: "mqtt://yutong/ytforward/shln/3",
		TS:             time.Date(2026, 7, 4, 23, 58, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600)),
		TotalKM:        120672,
	}

	agg := aggregateFromDailySource("2026-07-08", envelope.ProtocolYutongMQTT, current, previous, true)

	if agg.FirstKM != 120672 || agg.LatestKM != 120788 {
		t.Fatalf("km range = %v -> %v", agg.FirstKM, agg.LatestKM)
	}
	if agg.FirstEventTime != previous.TS || agg.LatestEventTime != current.TS {
		t.Fatalf("event range = %v -> %v", agg.FirstEventTime, agg.LatestEventTime)
	}
	if agg.QualityStatus != stats.QualityOK || agg.QualityReason != "historical_source_baseline" {
		t.Fatalf("quality = %s/%s", agg.QualityStatus, agg.QualityReason)
	}
	if agg.Count != 15 {
		t.Fatalf("sample count = %d, want 15", agg.Count)
	}
}

func TestAggregateFromDailySourceUsesCurrentFirstSampleWithoutHistory(t *testing.T) {
	current := dailySourceLast{
		VIN:            "LMRKH9AC2R1004087",
		SourceKey:      normalizedSourceKey("YUTONG_MQTT", "", "LMRKH9AC2R1004087", "mqtt://yutong/ytforward/shln/3"),
		DeviceID:       "LMRKH9AC2R1004087",
		SourceEndpoint: "mqtt://yutong/ytforward/shln/3",
		FirstTS:        time.Date(2026, 7, 8, 8, 0, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600)),
		TS:             time.Date(2026, 7, 8, 17, 0, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600)),
		FirstTotalKM:   120778,
		TotalKM:        120788,
		RawSampleCount: 15,
	}

	agg := aggregateFromDailySource("2026-07-08", envelope.ProtocolYutongMQTT, current, dailySourceLast{}, false)

	if agg.FirstKM != 120778 || agg.LatestKM != 120788 {
		t.Fatalf("km range = %v -> %v", agg.FirstKM, agg.LatestKM)
	}
	if agg.FirstEventTime != current.FirstTS || agg.LatestEventTime != current.TS {
		t.Fatalf("event range = %v -> %v", agg.FirstEventTime, agg.LatestEventTime)
	}
	if agg.QualityStatus != stats.QualityOK || agg.QualityReason != "current_day_first_sample" {
		t.Fatalf("quality = %s/%s", agg.QualityStatus, agg.QualityReason)
	}
}

func TestClearBackfillTargetMileageClearsExactKey(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("sqlmock.New() error = %v", err)
	}
	defer db.Close()
	mock.ExpectExec(`DELETE FROM vehicle_daily_mileage_source WHERE vin = \? AND stat_date = \? AND protocol = \?`).
		WithArgs("LA9GG64L7PBAF4001", "2026-07-08", "JT808").
		WillReturnResult(sqlmock.NewResult(0, 1))
	mock.ExpectExec(`DELETE FROM vehicle_daily_mileage WHERE vin = \? AND stat_date = \? AND protocol = \?`).
		WithArgs("LA9GG64L7PBAF4001", "2026-07-08", "JT808").
		WillReturnResult(sqlmock.NewResult(0, 1))
	if err := clearBackfillTargetMileage(context.Background(), db, "LA9GG64L7PBAF4001", "2026-07-08", envelope.ProtocolJT808); err != nil {
		t.Fatalf("clearBackfillTargetMileage() error = %v", err)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatalf("sql expectations: %v", err)
	}
}

func TestWriteAggregatesClearsTargetRowsBeforeStaleCandidateUpsert(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("sqlmock.New() error = %v", err)
	}
	defer db.Close()
	mock.MatchExpectationsInOrder(true)

	projNow := time.Date(2026, 7, 8, 12, 0, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600))
	aggregates := map[string]*metricAgg{
		"LA9GG64L7PBAF4001|2026-07-08|JT808|JT808:13307765812@115.231.168.135": {
			VIN:             "LA9GG64L7PBAF4001",
			Date:            "2026-07-08",
			Protocol:        envelope.ProtocolJT808,
			FirstKM:         4100,
			LatestKM:        4101,
			Count:           1,
			SourceKey:       "JT808:13307765812@115.231.168.135",
			Phone:           "13307765812",
			SourceEndpoint:  "115.231.168.135:20215",
			FirstEventTime:  projNow,
			LatestEventTime: projNow,
			QualityStatus:   stats.QualityInvalidDelta,
			QualityReason:   "outside_daily_range",
		},
	}

	mock.ExpectExec(`DELETE FROM vehicle_daily_mileage_source WHERE vin = \? AND stat_date = \? AND protocol = \?`).
		WithArgs("LA9GG64L7PBAF4001", "2026-07-08", "JT808").
		WillReturnResult(sqlmock.NewResult(0, 1))
	mock.ExpectExec(`DELETE FROM vehicle_daily_mileage WHERE vin = \? AND stat_date = \? AND protocol = \?`).
		WithArgs("LA9GG64L7PBAF4001", "2026-07-08", "JT808").
		WillReturnResult(sqlmock.NewResult(0, 1))
	mock.ExpectExec(`INSERT INTO vehicle_data_source`).
		WithArgs("JT808", "115.231.168.135", "115.231.168.135:20215", sqlmock.AnyArg(), sqlmock.AnyArg()).
		WillReturnResult(sqlmock.NewResult(0, 1))
	mock.ExpectExec(`INSERT INTO vehicle_daily_mileage_source`).
		WithArgs(
			"LA9GG64L7PBAF4001",
			"2026-07-08",
			"JT808",
			"JT808:13307765812@115.231.168.135",
			"115.231.168.135",
			"115.231.168.135:20215",
			"13307765812",
			"",
			"",
			float64(4100),
			float64(4101),
			float64(1),
			int64(1),
			projNow,
			projNow,
			stats.QualityInvalidDelta,
			"outside_daily_range",
		).
		WillReturnResult(sqlmock.NewResult(0, 1))
	mock.ExpectExec(`UPDATE vehicle_daily_mileage_source`).
		WithArgs("LA9GG64L7PBAF4001", "2026-07-08", "JT808").
		WillReturnResult(sqlmock.NewResult(0, 0))
	mock.ExpectExec(`INSERT INTO vehicle_daily_mileage`).
		WithArgs("LA9GG64L7PBAF4001", "2026-07-08", "JT808", int64(1000)).
		WillReturnResult(sqlmock.NewResult(1, 0))
	mock.ExpectExec(`UPDATE vehicle_daily_mileage_source s`).
		WithArgs(
			"LA9GG64L7PBAF4001",
			"2026-07-08",
			"JT808",
			int64(1000),
			"LA9GG64L7PBAF4001",
			"2026-07-08",
			"JT808",
		).
		WillReturnResult(sqlmock.NewResult(0, 0))
	mock.ExpectExec(`DELETE FROM vehicle_daily_mileage`).
		WithArgs(
			"LA9GG64L7PBAF4001",
			"2026-07-08",
			"JT808",
			"LA9GG64L7PBAF4001",
			"2026-07-08",
			"JT808",
		).
		WillReturnResult(sqlmock.NewResult(0, 1))

	written, err := writeAggregates(context.Background(), db, aggregates, 500)
	if err != nil {
		t.Fatalf("writeAggregates() error = %v", err)
	}
	if written != 1 {
		t.Fatalf("written = %d, want 1", written)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatalf("sql expectations: %v", err)
	}
}

func TestWriteAggregatesSkipsBlankSourceBeforeClearingTarget(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatalf("sqlmock.New() error = %v", err)
	}
	defer db.Close()

	written, err := writeAggregates(context.Background(), db, map[string]*metricAgg{
		"LA9GG64L7PBAF4001|2026-07-08|JT808|JT808:13307765812@": {
			VIN:             "LA9GG64L7PBAF4001",
			Date:            "2026-07-08",
			Protocol:        envelope.ProtocolJT808,
			FirstKM:         4100,
			LatestKM:        4101,
			Count:           1,
			SourceKey:       "JT808:13307765812@",
			Phone:           "13307765812",
			SourceEndpoint:  "",
			FirstEventTime:  time.Date(2026, 7, 8, 12, 0, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600)),
			LatestEventTime: time.Date(2026, 7, 8, 12, 0, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600)),
			QualityStatus:   stats.QualityNoPreviousBaseline,
			QualityReason:   "missing_previous_source",
		},
	}, 500)
	if err != nil {
		t.Fatalf("writeAggregates() error = %v", err)
	}
	if written != 0 {
		t.Fatalf("written = %d, want 0", written)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatalf("sql expectations: %v", err)
	}
}

func TestAddSamplesUsesCurrentDayFirstSampleBaseline(t *testing.T) {
	loc := time.FixedZone("Asia/Shanghai", 8*3600)
	firstSamples, err := stats.SamplesFromEnvelope(envelope.FrameEnvelope{
		Protocol:       envelope.ProtocolJT808,
		VIN:            "LA9GG64L7PBAF4001",
		Phone:          "13307765812",
		SourceEndpoint: "115.231.168.135:20215",
		EventTimeMS:    time.Date(2026, 7, 8, 12, 0, 0, 0, loc).UnixMilli(),
		Fields: map[string]any{
			"jt808.location.total_mileage_km": 4123.9,
		},
	}, loc)
	if err != nil {
		t.Fatalf("SamplesFromEnvelope() error = %v", err)
	}
	secondSamples, err := stats.SamplesFromEnvelope(envelope.FrameEnvelope{
		Protocol:       envelope.ProtocolJT808,
		VIN:            "LA9GG64L7PBAF4001",
		Phone:          "13307765812",
		SourceEndpoint: "115.231.168.135:20215",
		EventTimeMS:    time.Date(2026, 7, 8, 13, 0, 0, 0, loc).UnixMilli(),
		Fields: map[string]any{
			"jt808.location.total_mileage_km": 4129.9,
		},
	}, loc)
	if err != nil {
		t.Fatalf("SamplesFromEnvelope() error = %v", err)
	}
	aggregates := map[string]*metricAgg{}
	addSamples(aggregates, firstSamples)
	addSamples(aggregates, secondSamples)
	if len(aggregates) != 1 {
		t.Fatalf("aggregate count = %d, want 1", len(aggregates))
	}
	for _, agg := range aggregates {
		if agg.QualityStatus != stats.QualityOK {
			t.Fatalf("quality = %q, want %q", agg.QualityStatus, stats.QualityOK)
		}
		if agg.QualityReason != "current_day_first_sample" {
			t.Fatalf("quality reason = %q", agg.QualityReason)
		}
		if agg.FirstKM != 4123.9 || agg.LatestKM != 4129.9 {
			t.Fatalf("km range = %v -> %v", agg.FirstKM, agg.LatestKM)
		}
		if agg.FirstEventTime != time.Date(2026, 7, 8, 12, 0, 0, 0, loc) {
			t.Fatalf("first event time = %v", agg.FirstEventTime)
		}
	}
}

func TestLoadConfigDefaultsBackfillMethodToLastDiff(t *testing.T) {
	t.Setenv("BACKFILL_METHOD", "")
	t.Setenv("BACKFILL_DATE_FROM", "2026-07-08")
	t.Setenv("BACKFILL_DATE_TO", "2026-07-08")
	t.Setenv("BACKFILL_PROTOCOLS", "JT808")
	t.Setenv("LOCAL_TZ", "Asia/Shanghai")

	cfg, err := loadConfig()
	if err != nil {
		t.Fatalf("loadConfig() error = %v", err)
	}
	if cfg.Method != "last_diff" {
		t.Fatalf("method = %q, want last_diff", cfg.Method)
	}
}