package main

import (
	"context"
	"errors"
	"reflect"
	"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 TestDurableGPSBoundariesSurviveIncompleteRawAndRepeatedBackfill(t *testing.T) {
	loc := time.FixedZone("Asia/Shanghai", 8*3600)
	previous := time.Date(2026, 10, 20, 23, 59, 0, 0, loc)
	last := time.Date(2026, 10, 21, 23, 59, 0, 0, loc)
	old := stats.SourceMileageSample{VIN: "VIN", StatDate: "2026-10-21", Protocol: envelope.ProtocolJT808, SourceKey: "JT808:phone@PLATFORM:g7s", SourceEndpoint: "1.2.3.4:1", FirstEventTime: previous, FirstTotalKM: 100, LatestEventTime: last, LatestTotalKM: 120, DailyKM: 20, SampleCount: 200, QualityStatus: stats.QualityOK, QualityReason: stats.QualityReasonHistorical}
	partial := old
	partial.FirstEventTime, partial.FirstTotalKM = previous.Add(-24*time.Hour), 90
	partial.LatestEventTime, partial.LatestTotalKM = last.Add(-time.Hour), 115
	partial.SampleCount = 100
	for i := 0; i < 3; i++ {
		got := mergeProtectedGPSCandidate(old, partial)
		if !reflect.DeepEqual(got, old) {
			t.Fatalf("run %d replaced durable boundaries or double-counted: got=%+v old=%+v", i, got, old)
		}
		old = got
	}
	newer := partial
	newer.FirstEventTime, newer.FirstTotalKM = previous, 100
	newer.LatestEventTime, newer.LatestTotalKM = last.Add(time.Minute), 119
	got := mergeProtectedGPSCandidate(old, newer)
	if got.LatestTotalKM != 119 || got.DailyKM != 19 {
		t.Fatalf("event ordering incorrectly replaced with maximum odometer: %+v", got)
	}
}

func TestBackfillCurrentDayFirstBoundaryRetainsEarliestEvent(t *testing.T) {
	day := time.Date(2026, 10, 21, 8, 0, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600))
	if !preferDurableGPSFirst(day, day.Add(time.Hour), "2026-10-21") {
		t.Fatal("earliest current-day event lost")
	}
	if preferDurableGPSFirst(day.Add(-48*time.Hour), day.Add(-24*time.Hour), "2026-10-21") {
		t.Fatal("older previous-day baseline won")
	}
}

func gpsLockedRows() *sqlmock.Rows {
	return sqlmock.NewRows([]string{"source_key", "source_ip", "endpoint", "phone", "device", "platform", "first_km", "last_km", "daily_km", "hydrogen_km", "count", "hydrogen_count", "first_time", "last_time", "active", "known", "status", "reason", "selected"})
}

func TestGPSBackfillKeepsManualFinalAndRollsBackPartialWrites(t *testing.T) {
	for _, fail := range []bool{false, true} {
		db, mock, err := sqlmock.New()
		if err != nil {
			t.Fatal(err)
		}
		stamp := time.Date(2026, 10, 21, 23, 59, 0, 0, time.FixedZone("Asia/Shanghai", 8*3600))
		agg := &metricAgg{VIN: "VIN", Date: "2026-10-21", Protocol: envelope.ProtocolJT808, SourceKey: "JT808:phone@PLATFORM:g7s", SourceEndpoint: "1.2.3.4:123", FirstKM: 100, LatestKM: 120, FirstEventTime: stamp.Add(-24 * time.Hour), LatestEventTime: stamp, Count: 5, QualityStatus: stats.QualityOK, QualityReason: stats.QualityReasonHistorical}
		mock.ExpectBegin()
		mock.ExpectQuery("(?s)SELECT source_key.*FOR UPDATE").WithArgs("VIN", "2026-10-21").WillReturnRows(gpsLockedRows().AddRow("manual-report", "manual-import", "", "", "", "G7s", nil, nil, 88, 0, 1, 0, nil, nil, false, false, "OK", "manual_gps_report", true))
		mock.ExpectExec("INSERT INTO vehicle_data_source").WillReturnResult(sqlmock.NewResult(0, 1))
		if fail {
			mock.ExpectExec("INSERT INTO vehicle_daily_mileage_source").WillReturnError(errors.New("write failed"))
			mock.ExpectRollback()
		} else {
			mock.ExpectExec("(?s)INSERT INTO vehicle_daily_mileage_source.*sample_count=VALUES\\(sample_count\\)").WillReturnResult(sqlmock.NewResult(0, 1))
			// No clearing other candidates, source-count increment or final
			// projection is permitted over a selected manual report.
			mock.ExpectCommit()
		}
		n, err := writeAggregates(context.Background(), db, map[string]*metricAgg{"target": agg}, 500)
		if fail && (err == nil || n != 0) {
			t.Fatalf("failed target committed: n=%d err=%v", n, err)
		}
		if !fail && (err != nil || n != 1) {
			t.Fatalf("manual override write: n=%d err=%v", n, err)
		}
		if err := mock.ExpectationsWereMet(); err != nil {
			t.Fatal(err)
		}
		db.Close()
	}
}

func TestGPSNormalizationDoesNotRewriteSelectedManualEvidence(t *testing.T) {
	db, mock, err := sqlmock.New()
	if err != nil {
		t.Fatal(err)
	}
	defer db.Close()
	mock.ExpectBegin()
	mock.ExpectQuery("(?s)SELECT source_key.*FOR UPDATE").WithArgs("VIN", "2026-07-01").WillReturnRows(gpsLockedRows().AddRow("manual-report", "manual-import", "", "", "", "G7s", nil, nil, 88, 0, 1, 0, nil, nil, false, false, "OK", "manual_gps_report", true))
	// Do not normalize/delete the selected manual source, lose its selection
	// flag, or reproject over the manual final result.
	mock.ExpectCommit()
	if err := normalizeProtectedGPSDay(context.Background(), db, "VIN", "2026-07-01"); err != nil {
		t.Fatal(err)
	}
	if err := mock.ExpectationsWereMet(); err != nil {
		t.Fatal(err)
	}
}