package redisstate

import (
	"context"
	"io"
	"log/slog"
	"testing"
	"time"

	"galaxy/notification/internal/api/intentstream"
	"galaxy/notification/internal/config"
	"galaxy/notification/internal/service/acceptintent"
	"galaxy/notification/internal/service/malformedintent"

	"github.com/alicebob/miniredis/v2"
	"github.com/redis/go-redis/v9"
	"github.com/stretchr/testify/require"
)

func TestAcceptanceStoreCreateAcceptancePersistsNotificationRoutesAndSchedule(t *testing.T) {
	t.Parallel()

	server := miniredis.RunT(t)
	client := newTestRedisClient(t, server)

	store, err := NewAcceptanceStore(client, AcceptanceConfig{
		RecordTTL:      24 * time.Hour,
		DeadLetterTTL:  72 * time.Hour,
		IdempotencyTTL: 7 * 24 * time.Hour,
	})
	require.NoError(t, err)

	now := time.UnixMilli(1775121700000).UTC()
	input := validAdminAcceptanceInput(now)

	require.NoError(t, store.CreateAcceptance(context.Background(), input))

	notificationRecord, found, err := store.GetNotification(context.Background(), input.Notification.NotificationID)
	require.NoError(t, err)
	require.True(t, found)
	require.Equal(t, input.Notification.NotificationID, notificationRecord.NotificationID)

	idempotencyRecord, found, err := store.GetIdempotency(context.Background(), input.Idempotency.Producer, input.Idempotency.IdempotencyKey)
	require.NoError(t, err)
	require.True(t, found)
	require.Equal(t, input.Idempotency.RequestFingerprint, idempotencyRecord.RequestFingerprint)

	pushRoutePayload, err := client.Get(context.Background(), Keyspace{}.Route(input.Notification.NotificationID, "push:email:owner@example.com")).Bytes()
	require.NoError(t, err)
	pushRoute, err := UnmarshalRoute(pushRoutePayload)
	require.NoError(t, err)
	require.Equal(t, acceptintent.RouteStatusSkipped, pushRoute.Status)

	emailRouteKey := Keyspace{}.Route(input.Notification.NotificationID, "email:email:owner@example.com")
	emailRoutePayload, err := client.Get(context.Background(), emailRouteKey).Bytes()
	require.NoError(t, err)
	emailRoute, err := UnmarshalRoute(emailRoutePayload)
	require.NoError(t, err)
	require.Equal(t, acceptintent.RouteStatusPending, emailRoute.Status)

	scheduled, err := client.ZRangeWithScores(context.Background(), Keyspace{}.RouteSchedule(), 0, -1).Result()
	require.NoError(t, err)
	require.Len(t, scheduled, 1)
	require.Equal(t, emailRouteKey, scheduled[0].Member)
	require.Equal(t, float64(now.UnixMilli()), scheduled[0].Score)

	notificationTTL, err := client.PTTL(context.Background(), Keyspace{}.Notification(input.Notification.NotificationID)).Result()
	require.NoError(t, err)
	require.Greater(t, notificationTTL, 23*time.Hour)
	require.LessOrEqual(t, notificationTTL, 24*time.Hour)

	routeTTL, err := client.PTTL(context.Background(), emailRouteKey).Result()
	require.NoError(t, err)
	require.Greater(t, routeTTL, 23*time.Hour)
	require.LessOrEqual(t, routeTTL, 24*time.Hour)

	idempotencyTTL, err := client.PTTL(context.Background(), Keyspace{}.Idempotency(input.Idempotency.Producer, input.Idempotency.IdempotencyKey)).Result()
	require.NoError(t, err)
	require.Greater(t, idempotencyTTL, 6*24*time.Hour)
	require.LessOrEqual(t, idempotencyTTL, 7*24*time.Hour)
}

func TestMalformedIntentStoreRecordPersistsEntry(t *testing.T) {
	t.Parallel()

	server := miniredis.RunT(t)
	client := newTestRedisClient(t, server)

	store, err := NewMalformedIntentStore(client, 72*time.Hour)
	require.NoError(t, err)

	entry := malformedintent.Entry{
		StreamEntryID:    "1775121700000-0",
		NotificationType: "game.turn.ready",
		Producer:         "game_master",
		IdempotencyKey:   "game-123:turn-54",
		FailureCode:      malformedintent.FailureCodeInvalidPayload,
		FailureMessage:   "payload_json.turn_number is required",
		RawFields: map[string]any{
			"notification_type": "game.turn.ready",
		},
		RecordedAt: time.UnixMilli(1775121700000).UTC(),
	}

	require.NoError(t, store.Record(context.Background(), entry))

	payload, err := client.Get(context.Background(), Keyspace{}.MalformedIntent(entry.StreamEntryID)).Bytes()
	require.NoError(t, err)
	recordedEntry, err := UnmarshalMalformedIntent(payload)
	require.NoError(t, err)
	require.Equal(t, entry.StreamEntryID, recordedEntry.StreamEntryID)
	require.Equal(t, entry.FailureCode, recordedEntry.FailureCode)

	ttl, err := client.PTTL(context.Background(), Keyspace{}.MalformedIntent(entry.StreamEntryID)).Result()
	require.NoError(t, err)
	require.Greater(t, ttl, 71*time.Hour)
	require.LessOrEqual(t, ttl, 72*time.Hour)
}

func TestStreamOffsetStoreLoadAndSave(t *testing.T) {
	t.Parallel()

	server := miniredis.RunT(t)
	client := newTestRedisClient(t, server)

	store, err := NewStreamOffsetStore(client)
	require.NoError(t, err)

	_, found, err := store.Load(context.Background(), "notification:intents")
	require.NoError(t, err)
	require.False(t, found)

	require.NoError(t, store.Save(context.Background(), "notification:intents", "1775121700000-0"))

	entryID, found, err := store.Load(context.Background(), "notification:intents")
	require.NoError(t, err)
	require.True(t, found)
	require.Equal(t, "1775121700000-0", entryID)
}

func TestIntentStreamLagReaderReadsOldestUnprocessedEntry(t *testing.T) {
	t.Parallel()

	server := miniredis.RunT(t)
	client := newTestRedisClient(t, server)

	store, err := NewStreamOffsetStore(client)
	require.NoError(t, err)
	reader, err := NewIntentStreamLagReader(store, "notification:intents")
	require.NoError(t, err)

	firstID, err := client.XAdd(context.Background(), &redis.XAddArgs{
		Stream: "notification:intents",
		ID:     "1775121700000-0",
		Values: map[string]any{"payload": "first"},
	}).Result()
	require.NoError(t, err)
	secondID, err := client.XAdd(context.Background(), &redis.XAddArgs{
		Stream: "notification:intents",
		ID:     "1775121701000-0",
		Values: map[string]any{"payload": "second"},
	}).Result()
	require.NoError(t, err)

	snapshot, err := reader.ReadIntentStreamLagSnapshot(context.Background())
	require.NoError(t, err)
	require.NotNil(t, snapshot.OldestUnprocessedAt)
	require.Equal(t, time.UnixMilli(1775121700000).UTC(), *snapshot.OldestUnprocessedAt)

	require.NoError(t, store.Save(context.Background(), "notification:intents", firstID))
	snapshot, err = reader.ReadIntentStreamLagSnapshot(context.Background())
	require.NoError(t, err)
	require.NotNil(t, snapshot.OldestUnprocessedAt)
	require.Equal(t, time.UnixMilli(1775121701000).UTC(), *snapshot.OldestUnprocessedAt)

	require.NoError(t, store.Save(context.Background(), "notification:intents", secondID))
	snapshot, err = reader.ReadIntentStreamLagSnapshot(context.Background())
	require.NoError(t, err)
	require.Nil(t, snapshot.OldestUnprocessedAt)
}

func TestAcceptanceStoreWorksWithAcceptIntentService(t *testing.T) {
	t.Parallel()

	server := miniredis.RunT(t)
	client := newTestRedisClient(t, server)

	store, err := NewAcceptanceStore(client, AcceptanceConfig{
		RecordTTL:      24 * time.Hour,
		DeadLetterTTL:  72 * time.Hour,
		IdempotencyTTL: 7 * 24 * time.Hour,
	})
	require.NoError(t, err)

	service, err := acceptintent.New(acceptintent.Config{
		Store:            store,
		UserDirectory:    staticUserDirectory{},
		Clock:            fixedClock{now: time.UnixMilli(1775121700000).UTC()},
		Logger:           slog.New(slog.NewTextHandler(io.Discard, nil)),
		PushMaxAttempts:  3,
		EmailMaxAttempts: 7,
		IdempotencyTTL:   7 * 24 * time.Hour,
		AdminRouting: config.AdminRoutingConfig{
			LobbyApplicationSubmitted: []string{"owner@example.com"},
		},
	})
	require.NoError(t, err)

	result, err := service.Execute(context.Background(), acceptintent.AcceptInput{
		NotificationID: "1775121700000-0",
		Intent: intentstream.Intent{
			NotificationType: intentstream.NotificationTypeLobbyApplicationSubmitted,
			Producer:         intentstream.ProducerGameLobby,
			AudienceKind:     intentstream.AudienceKindAdminEmail,
			IdempotencyKey:   "game-456:application-submitted:user-42",
			OccurredAt:       time.UnixMilli(1775121700002).UTC(),
			PayloadJSON:      `{"applicant_name":"Nova Pilot","applicant_user_id":"user-42","game_id":"game-456","game_name":"Orion Front"}`,
		},
	})
	require.NoError(t, err)
	require.Equal(t, acceptintent.OutcomeAccepted, result.Outcome)

	record, found, err := store.GetNotification(context.Background(), "1775121700000-0")
	require.NoError(t, err)
	require.True(t, found)
	require.Equal(t, "1775121700000-0", record.NotificationID)
}

type fixedClock struct {
	now time.Time
}

func (clock fixedClock) Now() time.Time {
	return clock.now
}

func validAdminAcceptanceInput(now time.Time) acceptintent.CreateAcceptanceInput {
	return acceptintent.CreateAcceptanceInput{
		Notification: acceptintent.NotificationRecord{
			NotificationID:     "1775121700000-0",
			NotificationType:   intentstream.NotificationTypeLobbyApplicationSubmitted,
			Producer:           intentstream.ProducerGameLobby,
			AudienceKind:       intentstream.AudienceKindAdminEmail,
			PayloadJSON:        `{"applicant_name":"Nova Pilot","applicant_user_id":"user-42","game_id":"game-456","game_name":"Orion Front"}`,
			IdempotencyKey:     "game-456:application-submitted:user-42",
			RequestFingerprint: "sha256:deadbeef",
			OccurredAt:         now,
			AcceptedAt:         now,
			UpdatedAt:          now,
		},
		Routes: []acceptintent.NotificationRoute{
			{
				NotificationID: "1775121700000-0",
				RouteID:        "push:email:owner@example.com",
				Channel:        intentstream.ChannelPush,
				RecipientRef:   "email:owner@example.com",
				Status:         acceptintent.RouteStatusSkipped,
				AttemptCount:   0,
				MaxAttempts:    3,
				ResolvedEmail:  "owner@example.com",
				ResolvedLocale: "en",
				CreatedAt:      now,
				UpdatedAt:      now,
				SkippedAt:      now,
			},
			{
				NotificationID: "1775121700000-0",
				RouteID:        "email:email:owner@example.com",
				Channel:        intentstream.ChannelEmail,
				RecipientRef:   "email:owner@example.com",
				Status:         acceptintent.RouteStatusPending,
				AttemptCount:   0,
				MaxAttempts:    7,
				NextAttemptAt:  now,
				ResolvedEmail:  "owner@example.com",
				ResolvedLocale: "en",
				CreatedAt:      now,
				UpdatedAt:      now,
			},
		},
		Idempotency: acceptintent.IdempotencyRecord{
			Producer:           intentstream.ProducerGameLobby,
			IdempotencyKey:     "game-456:application-submitted:user-42",
			NotificationID:     "1775121700000-0",
			RequestFingerprint: "sha256:deadbeef",
			CreatedAt:          now,
			ExpiresAt:          now.Add(7 * 24 * time.Hour),
		},
	}
}

func newTestRedisClient(t *testing.T, server *miniredis.Miniredis) *redis.Client {
	t.Helper()

	client := redis.NewClient(&redis.Options{
		Addr:            server.Addr(),
		Protocol:        2,
		DisableIdentity: true,
	})
	t.Cleanup(func() {
		require.NoError(t, client.Close())
	})

	return client
}

type staticUserDirectory struct{}

func (staticUserDirectory) GetUserByID(context.Context, string) (acceptintent.UserRecord, error) {
	return acceptintent.UserRecord{}, acceptintent.ErrRecipientNotFound
}