implement paywall (#161)

* implement core foundation

* inject deps

* fix incorrect migration

* tail migration

* use transaction for migration

* fix: inject deps for tests

* cleanup billing management for admin

* upgrade stripe sdk to v85

* set price env variables

* cleanup billing management

* allow multiple dev windows

* fix: settings scroll

* feat: show nice video thumbnail in listview

* feat: implement freemium restrictions

* remove unnecessary comments

* refactor

* docs

* format

* tweak network settings better hierarchy

go/internal/network/service.go

@@ -9,8 +9,11 @@ import (
 	"strings"
 
 	pbaero "github.com/flowy-live/llink/genproto/aero"
+	"github.com/flowy-live/llink/internal/billing"
 	"github.com/flowy-live/llink/internal/utils"
+	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
+	"slices"
 )
 
 var ErrNotFound = errors.New("network not found")
@@ -25,8 +28,11 @@ type Service interface {
 	GetByID(ctx context.Context, id string) (*Network, error)
 	// SetName returns ErrNotFound or ErrInvalidName.
 	SetName(ctx context.Context, id, name string) error
+	// AddMembers inserts members and syncs the new seat count to billing
+	// atomically; a Stripe failure rolls the insert back.
 	AddMembers(ctx context.Context, networkID string, humanIds []string) error
 	RemoveMember(ctx context.Context, networkID, humanId string) error
+	CountSeats(ctx context.Context, networkID string) (int, error)
 	ListForHuman(ctx context.Context, humanId string) ([]*Network, error)
 	IsMember(ctx context.Context, networkID, humanId string) (bool, error)
 	// ListAll returns all networks with their members
@@ -41,12 +47,19 @@ type Service interface {
 }
 
 type serviceImpl struct {
-	repo    repository
-	aeroSvc pbaero.PrimaryClient
+	pool       *pgxpool.Pool
+	repo       repository
+	aeroSvc    pbaero.PrimaryClient
+	billingSvc billing.Service
 }
 
-func NewService(pool *pgxpool.Pool, aeroSvc pbaero.PrimaryClient) Service {
-	return &serviceImpl{repo: newRepository(pool), aeroSvc: aeroSvc}
+func NewService(pool *pgxpool.Pool, aeroSvc pbaero.PrimaryClient, billingSvc billing.Service) Service {
+	return &serviceImpl{
+		pool:       pool,
+		repo:       newRepository(pool),
+		aeroSvc:    aeroSvc,
+		billingSvc: billingSvc,
+	}
 }
 
 func (s *serviceImpl) Create(ctx context.Context, name, adminHumanId string) (*Network, error) {
@@ -60,8 +73,7 @@ func (s *serviceImpl) Create(ctx context.Context, name, adminHumanId string) (*N
 		return nil, err
 	}
 
-	err = s.AddMembers(ctx, network.ID, []string{adminHumanId})
-	if err != nil {
+	if err := s.AddMembers(ctx, network.ID, []string{adminHumanId}); err != nil {
 		return nil, err
 	}
 
@@ -90,22 +102,58 @@ func (s *serviceImpl) SetName(ctx context.Context, id, name string) error {
 }
 
 func (s *serviceImpl) AddMembers(ctx context.Context, networkID string, humanIds []string) error {
-	for _, humanId := range humanIds {
-		if humanId == "" {
-			return fmt.Errorf("invalid humanId")
-		}
-		if err := s.repo.addMember(ctx, networkID, humanId); err != nil {
-			return err
-		}
+	if slices.Contains(humanIds, "") {
+		return fmt.Errorf("invalid humanId")
 	}
-	return nil
+	return s.mutateMembers(ctx, networkID, func(tx pgx.Tx) error {
+		for _, humanId := range humanIds {
+			if err := s.repo.addMember(ctx, tx, networkID, humanId); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
 }
 
 func (s *serviceImpl) RemoveMember(ctx context.Context, networkID, humanId string) error {
 	if humanId == "" {
 		return fmt.Errorf("invalid humanId")
 	}
-	return s.repo.removeMember(ctx, networkID, humanId)
+	return s.mutateMembers(ctx, networkID, func(tx pgx.Tx) error {
+		return s.repo.removeMember(ctx, tx, networkID, humanId)
+	})
+}
+
+// mutateMembers runs fn in a tx, recounts seats, calls billing.SyncSeats,
+// and commits. Any error rolls the membership change back.
+func (s *serviceImpl) mutateMembers(ctx context.Context, networkID string, fn func(pgx.Tx) error) error {
+	tx, err := s.pool.Begin(ctx)
+	if err != nil {
+		return fmt.Errorf("begin tx: %w", err)
+	}
+	defer tx.Rollback(ctx)
+
+	if err := fn(tx); err != nil {
+		return err
+	}
+
+	seats, err := s.repo.countSeats(ctx, tx, networkID)
+	if err != nil {
+		return fmt.Errorf("count seats: %w", err)
+	}
+
+	if err := s.billingSvc.SyncSeats(ctx, networkID, seats); err != nil {
+		return fmt.Errorf("sync billing seats: %w", err)
+	}
+
+	if err := tx.Commit(ctx); err != nil {
+		return fmt.Errorf("commit tx: %w", err)
+	}
+	return nil
+}
+
+func (s *serviceImpl) CountSeats(ctx context.Context, networkID string) (int, error) {
+	return s.repo.countSeats(ctx, s.pool, networkID)
 }
 
 func (s *serviceImpl) ListForHuman(ctx context.Context, humanId string) ([]*Network, error) {
@@ -126,8 +174,6 @@ func (s *serviceImpl) ListAll(ctx context.Context) ([]*Network, error) {
 	return s.repo.listAll(ctx)
 }
 
-// Invitation methods
-
 func (s *serviceImpl) InviteByEmail(ctx context.Context, networkID string, emails []string) error {
 	network, err := s.repo.getByID(ctx, networkID)
 	if err != nil {
@@ -180,10 +226,13 @@ func (s *serviceImpl) AcceptInvitation(ctx context.Context, networkID, email, hu
 		return fmt.Errorf("invalid humanId")
 	}
 
-	if err := s.repo.deleteInvitation(ctx, networkID, normalized); err != nil {
-		return err
-	}
-	return s.repo.addMember(ctx, networkID, humanId)
+	return s.mutateMembers(ctx, networkID, func(tx pgx.Tx) error {
+		err := s.repo.deleteInvitation(ctx, tx, networkID, normalized)
+		if err != nil {
+			return err
+		}
+		return s.repo.addMember(ctx, tx, networkID, humanId)
+	})
 }
 
 func (s *serviceImpl) RevokeInvitation(ctx context.Context, networkID, email string) error {
@@ -191,7 +240,7 @@ func (s *serviceImpl) RevokeInvitation(ctx context.Context, networkID, email str
 	if err != nil {
 		return fmt.Errorf("invalid email: %w", err)
 	}
-	return s.repo.deleteInvitation(ctx, networkID, normalized)
+	return s.repo.deleteInvitation(ctx, s.pool, networkID, normalized)
 }
 
 func buildInvitationHTML(networkName string) string {