package postgres

import (
	"context"
	"encoding/json"
	"strings"
	"testing"
	"time"

	fkevent "gitea.maximumdirect.net/ejr/feedkit/event"
	fksinks "gitea.maximumdirect.net/ejr/feedkit/sinks"
	"gitea.maximumdirect.net/ejr/weatherfeeder/model"
	"gitea.maximumdirect.net/ejr/weatherfeeder/standards"
)

func TestMapPostgresEventObservationStructPayload(t *testing.T) {
	isDay := true
	temp := 21.5
	obs := model.WeatherObservation{
		StationID:       "KSTL",
		StationName:     "St. Louis",
		Timestamp:       time.Date(2026, 3, 16, 19, 0, 0, 0, time.UTC),
		ConditionCode:   model.WMOCode(1),
		IsDay:           &isDay,
		TextDescription: "few clouds",
		TemperatureC:    &temp,
		PresentWeather:  []model.PresentWeather{{Raw: map[string]any{"a": 1, "b": "x"}}},
	}

	writes, err := mapPostgresEvent(context.Background(), testEvent(standards.SchemaWeatherObservationV1, "observation", obs))
	if err != nil {
		t.Fatalf("mapPostgresEvent() error = %v", err)
	}
	if len(writes) != 2 {
		t.Fatalf("mapPostgresEvent() writes len = %d, want 2", len(writes))
	}
	if writes[0].Table != tableObservations {
		t.Fatalf("writes[0].Table = %q, want %q", writes[0].Table, tableObservations)
	}
	if got := writes[0].Values["station_id"]; got != "KSTL" {
		t.Fatalf("observations station_id = %#v, want KSTL", got)
	}
	if writes[1].Table != tableObservationPresentWeather {
		t.Fatalf("writes[1].Table = %q, want %q", writes[1].Table, tableObservationPresentWeather)
	}
	if got := writes[1].Values["raw_text"]; got != `{"a":1,"b":"x"}` {
		t.Fatalf("present_weather raw_text = %#v, want compact JSON", got)
	}

	assertAllWritesIncludeAllColumns(t, writes)
}

func TestMapPostgresEventForecastStructPayload(t *testing.T) {
	isDay := true
	temp := 10.5
	run := model.WeatherForecastRun{
		LocationID:   "LOC-1",
		LocationName: "St. Louis",
		IssuedAt:     time.Date(2026, 3, 16, 18, 0, 0, 0, time.UTC),
		Product:      model.ForecastProductHourly,
		Periods: []model.WeatherForecastPeriod{
			{
				StartTime:     time.Date(2026, 3, 16, 19, 0, 0, 0, time.UTC),
				EndTime:       time.Date(2026, 3, 16, 20, 0, 0, 0, time.UTC),
				IsDay:         &isDay,
				ConditionCode: model.WMOCode(2),
				TemperatureC:  &temp,
			},
			{
				StartTime:     time.Date(2026, 3, 16, 20, 0, 0, 0, time.UTC),
				EndTime:       time.Date(2026, 3, 16, 21, 0, 0, 0, time.UTC),
				ConditionCode: model.WMOCode(3),
			},
		},
	}

	writes, err := mapPostgresEvent(context.Background(), testEvent(standards.SchemaWeatherForecastV1, "forecast", run))
	if err != nil {
		t.Fatalf("mapPostgresEvent() error = %v", err)
	}
	if len(writes) != 3 {
		t.Fatalf("mapPostgresEvent() writes len = %d, want 3", len(writes))
	}

	if writes[0].Table != tableForecasts {
		t.Fatalf("writes[0].Table = %q, want %q", writes[0].Table, tableForecasts)
	}
	if got := writes[0].Values["period_count"]; got != 2 {
		t.Fatalf("forecasts period_count = %#v, want 2", got)
	}
	if writes[1].Table != tableForecastPeriods || writes[2].Table != tableForecastPeriods {
		t.Fatalf("forecast period writes not in expected order")
	}
	if got := writes[1].Values["period_index"]; got != 0 {
		t.Fatalf("first period index = %#v, want 0", got)
	}

	assertAllWritesIncludeAllColumns(t, writes)
}

func TestMapPostgresEventAlertStructPayload(t *testing.T) {
	sent := time.Date(2026, 3, 16, 17, 0, 0, 0, time.UTC)
	run := model.WeatherAlertRun{
		AsOf: time.Date(2026, 3, 16, 18, 0, 0, 0, time.UTC),
		Alerts: []model.WeatherAlert{
			{
				ID:       "urn:alert:1",
				Headline: "Winter Weather Advisory",
				Severity: "Moderate",
				References: []model.AlertReference{
					{ID: "urn:ref:1", Sent: &sent},
					{Identifier: "ref-two"},
				},
			},
			{
				ID:       "urn:alert:2",
				Headline: "Second alert",
			},
		},
	}

	writes, err := mapPostgresEvent(context.Background(), testEvent(standards.SchemaWeatherAlertV1, "alert", run))
	if err != nil {
		t.Fatalf("mapPostgresEvent() error = %v", err)
	}
	if len(writes) != 5 {
		t.Fatalf("mapPostgresEvent() writes len = %d, want 5", len(writes))
	}

	counts := map[string]int{}
	for _, w := range writes {
		counts[w.Table]++
	}
	if counts[tableAlertRuns] != 1 || counts[tableAlerts] != 2 || counts[tableAlertReferences] != 2 {
		t.Fatalf("unexpected table write counts: %#v", counts)
	}

	firstAlert, ok := firstWriteForTable(writes, tableAlerts)
	if !ok {
		t.Fatalf("missing alerts write")
	}
	if got := firstAlert.Values["reference_count"]; got != 2 {
		t.Fatalf("alerts reference_count = %#v, want 2", got)
	}

	assertAllWritesIncludeAllColumns(t, writes)
}

func TestMapPostgresEventMapPayload(t *testing.T) {
	run := model.WeatherForecastRun{
		IssuedAt: time.Date(2026, 3, 16, 18, 0, 0, 0, time.UTC),
		Product:  model.ForecastProductHourly,
		Periods: []model.WeatherForecastPeriod{
			{
				StartTime:     time.Date(2026, 3, 16, 19, 0, 0, 0, time.UTC),
				EndTime:       time.Date(2026, 3, 16, 20, 0, 0, 0, time.UTC),
				ConditionCode: model.WMOCode(2),
			},
		},
	}
	b, err := json.Marshal(run)
	if err != nil {
		t.Fatalf("json.Marshal() error = %v", err)
	}
	var payload map[string]any
	if err := json.Unmarshal(b, &payload); err != nil {
		t.Fatalf("json.Unmarshal() error = %v", err)
	}

	writes, err := mapPostgresEvent(context.Background(), testEvent(standards.SchemaWeatherForecastV1, "forecast", payload))
	if err != nil {
		t.Fatalf("mapPostgresEvent() error = %v", err)
	}
	if len(writes) != 2 {
		t.Fatalf("mapPostgresEvent() writes len = %d, want 2", len(writes))
	}
	if writes[0].Table != tableForecasts {
		t.Fatalf("writes[0].Table = %q, want %q", writes[0].Table, tableForecasts)
	}

	assertAllWritesIncludeAllColumns(t, writes)
}

func TestMapPostgresEventUnknownSchemaNoOp(t *testing.T) {
	writes, err := mapPostgresEvent(context.Background(), testEvent("weather.unknown.v1", "observation", map[string]any{"x": 1}))
	if err != nil {
		t.Fatalf("mapPostgresEvent() error = %v", err)
	}
	if len(writes) != 0 {
		t.Fatalf("mapPostgresEvent() writes len = %d, want 0", len(writes))
	}
}

func TestMapPostgresEventMalformedPayload(t *testing.T) {
	_, err := mapPostgresEvent(context.Background(), testEvent(standards.SchemaWeatherForecastV1, "forecast", "bad"))
	if err == nil {
		t.Fatalf("mapPostgresEvent() expected error for malformed payload")
	}
	if !strings.Contains(err.Error(), "decode forecast payload") {
		t.Fatalf("error = %q, want decode forecast payload context", err)
	}
}

func testEvent(schema string, kind fkevent.Kind, payload any) fkevent.Event {
	effectiveAt := time.Date(2026, 3, 16, 18, 30, 0, 0, time.UTC)
	return fkevent.Event{
		ID:          "evt-1",
		Kind:        kind,
		Source:      "test-source",
		Schema:      schema,
		EmittedAt:   time.Date(2026, 3, 16, 18, 31, 0, 0, time.UTC),
		EffectiveAt: &effectiveAt,
		Payload:     payload,
	}
}

func firstWriteForTable(writes []fksinks.PostgresWrite, table string) (fksinks.PostgresWrite, bool) {
	for _, w := range writes {
		if w.Table == table {
			return w, true
		}
	}
	return fksinks.PostgresWrite{}, false
}

func assertAllWritesIncludeAllColumns(t *testing.T, writes []fksinks.PostgresWrite) {
	t.Helper()
	colCounts := tableColumnCounts()
	for i, w := range writes {
		expectedCount, ok := colCounts[w.Table]
		if !ok {
			t.Fatalf("writes[%d] references unknown table %q", i, w.Table)
		}
		if len(w.Values) != expectedCount {
			t.Fatalf("writes[%d] table=%q has %d values, want %d", i, w.Table, len(w.Values), expectedCount)
		}
	}
}

func tableColumnCounts() map[string]int {
	s := weatherPostgresSchema()
	m := make(map[string]int, len(s.Tables))
	for _, tbl := range s.Tables {
		m[tbl.Name] = len(tbl.Columns)
	}
	return m
}