package approveapplication_test

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

	"galaxy/lobby/internal/adapters/applicationinmem"
	"galaxy/lobby/internal/adapters/gameinmem"
	"galaxy/lobby/internal/adapters/gapactivationinmem"
	"galaxy/lobby/internal/adapters/membershipinmem"
	"galaxy/lobby/internal/adapters/mocks"
	"galaxy/lobby/internal/adapters/racenameinmem"
	"galaxy/lobby/internal/domain/application"
	"galaxy/lobby/internal/domain/common"
	"galaxy/lobby/internal/domain/game"
	"galaxy/lobby/internal/domain/membership"
	"galaxy/lobby/internal/ports"
	"galaxy/lobby/internal/service/approveapplication"
	"galaxy/lobby/internal/service/shared"
	"galaxy/notificationintent"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"go.uber.org/mock/gomock"
)

type intentRec struct {
	mu        sync.Mutex
	published []notificationintent.Intent
	err       error
}

func (r *intentRec) record(_ context.Context, intent notificationintent.Intent) (string, error) {
	r.mu.Lock()
	defer r.mu.Unlock()
	if r.err != nil {
		return "", r.err
	}
	r.published = append(r.published, intent)
	return "1", nil
}

func (r *intentRec) snapshot() []notificationintent.Intent {
	r.mu.Lock()
	defer r.mu.Unlock()
	return append([]notificationintent.Intent(nil), r.published...)
}

func (r *intentRec) setErr(err error) {
	r.mu.Lock()
	defer r.mu.Unlock()
	r.err = err
}

func newIntentMock(t *testing.T, rec *intentRec) *mocks.MockIntentPublisher {
	t.Helper()
	m := mocks.NewMockIntentPublisher(gomock.NewController(t))
	m.EXPECT().Publish(gomock.Any(), gomock.Any()).DoAndReturn(rec.record).AnyTimes()
	return m
}

func silentLogger() *slog.Logger { return slog.New(slog.NewTextHandler(io.Discard, nil)) }

func fixedClock(at time.Time) func() time.Time { return func() time.Time { return at } }

type fixedIDs struct {
	gameID        common.GameID
	applicationID common.ApplicationID
	membershipID  common.MembershipID
}

func (f fixedIDs) NewGameID() (common.GameID, error)               { return f.gameID, nil }
func (f fixedIDs) NewApplicationID() (common.ApplicationID, error) { return f.applicationID, nil }
func (f fixedIDs) NewInviteID() (common.InviteID, error)           { return "", errors.New("not used") }
func (f fixedIDs) NewMembershipID() (common.MembershipID, error)   { return f.membershipID, nil }

type fixture struct {
	now              time.Time
	games            *gameinmem.Store
	memberships      *membershipinmem.Store
	applications     *applicationinmem.Store
	directory        *racenameinmem.Directory
	gapStore         *gapactivationinmem.Store
	intentRec        *intentRec
	intents          *mocks.MockIntentPublisher
	ids              fixedIDs
	openPublicGameID common.GameID
}

func newFixture(t *testing.T, maxPlayers, gapPlayers int) *fixture {
	t.Helper()
	now := time.Date(2026, 4, 25, 10, 0, 0, 0, time.UTC)
	dir, err := racenameinmem.NewDirectory(racenameinmem.WithClock(fixedClock(now)))
	require.NoError(t, err)
	games := gameinmem.NewStore()
	memberships := membershipinmem.NewStore()
	applications := applicationinmem.NewStore()

	gameRecord, err := game.New(game.NewGameInput{
		GameID:              "game-public",
		GameName:            "Galactic Open",
		GameType:            game.GameTypePublic,
		MinPlayers:          2,
		MaxPlayers:          maxPlayers,
		StartGapHours:       2,
		StartGapPlayers:     gapPlayers,
		EnrollmentEndsAt:    now.Add(24 * time.Hour),
		TurnSchedule:        "0 */6 * * *",
		TargetEngineVersion: "1.0.0",
		Now:                 now,
	})
	require.NoError(t, err)
	gameRecord.Status = game.StatusEnrollmentOpen
	require.NoError(t, games.Save(context.Background(), gameRecord))

	rec := &intentRec{}
	return &fixture{
		now:              now,
		games:            games,
		memberships:      memberships,
		applications:     applications,
		directory:        dir,
		gapStore:         gapactivationinmem.NewStore(),
		intentRec:        rec,
		intents:          newIntentMock(t, rec),
		ids:              fixedIDs{membershipID: "membership-fixed"},
		openPublicGameID: gameRecord.GameID,
	}
}

func newService(t *testing.T, f *fixture) *approveapplication.Service {
	t.Helper()
	svc, err := approveapplication.NewService(approveapplication.Dependencies{
		Games:        f.games,
		Memberships:  f.memberships,
		Applications: f.applications,
		Directory:    f.directory,
		GapStore:     f.gapStore,
		Intents:      f.intents,
		IDs:          f.ids,
		Clock:        fixedClock(f.now),
		Logger:       silentLogger(),
	})
	require.NoError(t, err)
	return svc
}

func seedSubmittedApplication(t *testing.T, f *fixture, applicationID common.ApplicationID, userID, raceName string) application.Application {
	t.Helper()
	app, err := application.New(application.NewApplicationInput{
		ApplicationID:   applicationID,
		GameID:          f.openPublicGameID,
		ApplicantUserID: userID,
		RaceName:        raceName,
		Now:             f.now,
	})
	require.NoError(t, err)
	require.NoError(t, f.applications.Save(context.Background(), app))
	return app
}

func TestApproveHappyPath(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")
	svc := newService(t, f)

	got, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.NoError(t, err)
	assert.Equal(t, common.MembershipID("membership-fixed"), got.MembershipID)
	assert.Equal(t, "SolarPilot", got.RaceName)
	assert.Equal(t, "solarpilot", got.CanonicalKey)
	assert.Equal(t, membership.StatusActive, got.Status)
	assert.Equal(t, f.now, got.JoinedAt)

	updated, err := f.applications.Get(context.Background(), app.ApplicationID)
	require.NoError(t, err)
	assert.Equal(t, application.StatusApproved, updated.Status)

	availability, err := f.directory.Check(context.Background(), "SolarPilot", "user-2")
	require.NoError(t, err)
	assert.True(t, availability.Taken)
	assert.Equal(t, "user-1", availability.HolderUserID)

	intents := f.intentRec.snapshot()
	require.Len(t, intents, 1)
	assert.Equal(t, notificationintent.NotificationTypeLobbyMembershipApproved, intents[0].NotificationType)
	assert.Equal(t, []string{"user-1"}, intents[0].RecipientUserIDs)

	assert.False(t, f.gapStore.WasActivated(f.openPublicGameID))
}

func TestApproveActivatesGapAtMaxPlayers(t *testing.T) {
	t.Parallel()
	// max=2, gap=1; pre-seed 1 active member. Approval pushes count to 2 (== max).
	f := newFixture(t, 2, 1)
	preexisting, err := membership.New(membership.NewMembershipInput{
		MembershipID: "membership-pre",
		GameID:       f.openPublicGameID,
		UserID:       "user-pre",
		RaceName:     "VoidRunner",
		CanonicalKey: "voidrunner",
		Now:          f.now,
	})
	require.NoError(t, err)
	require.NoError(t, f.memberships.Save(context.Background(), preexisting))

	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")
	svc := newService(t, f)

	_, err = svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.NoError(t, err)
	assert.True(t, f.gapStore.WasActivated(f.openPublicGameID))
	assert.Equal(t, f.now, f.gapStore.ActivatedAt(f.openPublicGameID))
}

func TestApproveDoesNotActivateGapBelowMax(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")
	svc := newService(t, f)

	_, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.NoError(t, err)
	assert.False(t, f.gapStore.WasActivated(f.openPublicGameID))
}

func TestApproveUserActorForbidden(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")
	svc := newService(t, f)

	_, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewUserActor("user-1"),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.ErrorIs(t, err, shared.ErrForbidden)
}

func TestApproveApplicationNotFound(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	svc := newService(t, f)

	_, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: "application-missing",
	})
	require.ErrorIs(t, err, application.ErrNotFound)
}

func TestApproveCrossGameApplicationNotFound(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")
	svc := newService(t, f)

	_, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        "game-other",
		ApplicationID: app.ApplicationID,
	})
	require.ErrorIs(t, err, application.ErrNotFound)
}

func TestApproveAlreadyDecidedConflict(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")
	require.NoError(t, f.applications.UpdateStatus(context.Background(), ports.UpdateApplicationStatusInput{
		ApplicationID: app.ApplicationID,
		ExpectedFrom:  application.StatusSubmitted,
		To:            application.StatusRejected,
		At:            f.now,
	}))

	svc := newService(t, f)
	_, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.ErrorIs(t, err, application.ErrConflict)
}

func TestApproveGameNotEnrollmentOpenConflict(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")

	rec, err := f.games.Get(context.Background(), f.openPublicGameID)
	require.NoError(t, err)
	rec.Status = game.StatusReadyToStart
	require.NoError(t, f.games.Save(context.Background(), rec))

	svc := newService(t, f)
	_, err = svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.ErrorIs(t, err, game.ErrConflict)
}

func TestApproveRosterFullConflict(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 2, 1)
	for i := range 3 {
		member, err := membership.New(membership.NewMembershipInput{
			MembershipID: common.MembershipID("membership-seed-" + string(rune('a'+i))),
			GameID:       f.openPublicGameID,
			UserID:       "seed-user-" + string(rune('a'+i)),
			RaceName:     "Seed " + string(rune('A'+i)),
			CanonicalKey: "seed" + string(rune('a'+i)),
			Now:          f.now,
		})
		require.NoError(t, err)
		require.NoError(t, f.memberships.Save(context.Background(), member))
	}
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")

	svc := newService(t, f)
	_, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.ErrorIs(t, err, game.ErrConflict)
}

func TestApproveNameTakenByAnotherUser(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	require.NoError(t, f.directory.Reserve(context.Background(), "game-other", "user-other", "SolarPilot"))
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")

	svc := newService(t, f)
	_, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.ErrorIs(t, err, ports.ErrNameTaken)

	availability, err := f.directory.Check(context.Background(), "SolarPilot", "user-1")
	require.NoError(t, err)
	assert.True(t, availability.Taken)
	assert.Equal(t, "user-other", availability.HolderUserID)
}

// approveCASStub wraps applicationinmem.Store but injects ErrConflict on
// the next UpdateStatus call so we can observe the rollback path.
type approveCASStub struct {
	*applicationinmem.Store
	failNext bool
}

func (s *approveCASStub) UpdateStatus(ctx context.Context, input ports.UpdateApplicationStatusInput) error {
	if s.failNext {
		s.failNext = false
		return application.ErrConflict
	}
	return s.Store.UpdateStatus(ctx, input)
}

func TestApproveCASConflictReleasesReservation(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")

	cas := &approveCASStub{Store: f.applications, failNext: true}
	svc, err := approveapplication.NewService(approveapplication.Dependencies{
		Games:        f.games,
		Memberships:  f.memberships,
		Applications: cas,
		Directory:    f.directory,
		GapStore:     f.gapStore,
		Intents:      f.intents,
		IDs:          f.ids,
		Clock:        fixedClock(f.now),
		Logger:       silentLogger(),
	})
	require.NoError(t, err)

	_, err = svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.ErrorIs(t, err, application.ErrConflict)

	availability, err := f.directory.Check(context.Background(), "SolarPilot", "user-2")
	require.NoError(t, err)
	assert.False(t, availability.Taken, "reservation must have been released after CAS failure")
	assert.Empty(t, availability.HolderUserID)
}

func TestApprovePublishFailureDoesNotRollback(t *testing.T) {
	t.Parallel()
	f := newFixture(t, 4, 1)
	app := seedSubmittedApplication(t, f, "application-1", "user-1", "SolarPilot")
	f.intentRec.setErr(errors.New("publish failed"))

	svc := newService(t, f)
	got, err := svc.Handle(context.Background(), approveapplication.Input{
		Actor:         shared.NewAdminActor(),
		GameID:        f.openPublicGameID,
		ApplicationID: app.ApplicationID,
	})
	require.NoError(t, err)
	assert.Equal(t, common.MembershipID("membership-fixed"), got.MembershipID)

	updated, err := f.applications.Get(context.Background(), app.ApplicationID)
	require.NoError(t, err)
	assert.Equal(t, application.StatusApproved, updated.Status)
}