add service

internal/repository/interfaces.go

@@ -12,6 +12,7 @@ type UserRepository interface {
 	FindByEmailHash(ctx context.Context, emailHash string) (*model.User, error)
 	FindByID(ctx context.Context, userID int) (*model.User, error)
 	Create(ctx context.Context, user *model.User) error
+	CreateTx(ctx context.Context, tx pgx.Tx, user *model.User) error
 	UpdateBalance(ctx context.Context, userID int, delta float64) error
 	UpdateBalanceTx(ctx context.Context, tx pgx.Tx, userID int, delta float64) error
 	GetBalance(ctx context.Context, userID int) (float64, error)
@@ -35,7 +36,9 @@ type InviteRepository interface {
 	Create(ctx context.Context, invite *model.InviteCode) error
 	CreateTx(ctx context.Context, tx pgx.Tx, invite *model.InviteCode) error
 	FindByCode(ctx context.Context, code int64) (*model.InviteCode, error)
+	FindActiveByCode(ctx context.Context, code int64) (*model.InviteCode, error)
 	IncrementUsedCount(ctx context.Context, code int64) error
+	DecrementCanBeUsedCountTx(ctx context.Context, tx pgx.Tx, code int64) error
 	DeactivateExpired(ctx context.Context) (int, error)
 	GetUserInvites(ctx context.Context, userID int) ([]*model.InviteCode, error)
 }

internal/repository/invite.go

@@ -78,6 +78,38 @@ func (r *inviteRepository) FindByCode(ctx context.Context, code int64) (*model.I
 	return invite, nil
 }
 
+func (r *inviteRepository) FindActiveByCode(ctx context.Context, code int64) (*model.InviteCode, error) {
+	query := r.qb.Select(
+		"id", "user_id", "code", "can_be_used_count", "used_count",
+		"is_active", "created_at", "expires_at",
+	).From("invite_codes").Where(sq.And{
+		sq.Eq{"code": code},
+		sq.Eq{"is_active": true},
+		sq.Expr("expires_at > now()"),
+		sq.Expr("can_be_used_count > used_count"),
+	})
+
+	sqlQuery, args, err := query.ToSql()
+	if err != nil {
+		return nil, errs.NewInternalError(errs.DatabaseError, "failed to build query", err)
+	}
+
+	invite := &model.InviteCode{}
+	err = r.pool.QueryRow(ctx, sqlQuery, args...).Scan(
+		&invite.ID, &invite.UserID, &invite.Code, &invite.CanBeUsedCount,
+		&invite.UsedCount, &invite.IsActive, &invite.CreatedAt, &invite.ExpiresAt,
+	)
+
+	if errors.Is(err, pgx.ErrNoRows) {
+		return nil, errs.NewBusinessError(errs.InviteInvalidOrExpired, "invite code is invalid or expired")
+	}
+	if err != nil {
+		return nil, errs.NewInternalError(errs.DatabaseError, "failed to find active invite code", err)
+	}
+
+	return invite, nil
+}
+
 func (r *inviteRepository) IncrementUsedCount(ctx context.Context, code int64) error {
 	query := r.qb.Update("invite_codes").
 		Set("used_count", sq.Expr("used_count + 1")).
@@ -96,6 +128,25 @@ func (r *inviteRepository) IncrementUsedCount(ctx context.Context, code int64) e
 	return nil
 }
 
+func (r *inviteRepository) DecrementCanBeUsedCountTx(ctx context.Context, tx pgx.Tx, code int64) error {
+	query := r.qb.Update("invite_codes").
+		Set("used_count", sq.Expr("used_count + 1")).
+		Set("is_active", sq.Expr("CASE WHEN used_count + 1 >= can_be_used_count THEN false ELSE is_active END")).
+		Where(sq.Eq{"code": code})
+
+	sqlQuery, args, err := query.ToSql()
+	if err != nil {
+		return errs.NewInternalError(errs.DatabaseError, "failed to build query", err)
+	}
+
+	_, err = tx.Exec(ctx, sqlQuery, args...)
+	if err != nil {
+		return errs.NewInternalError(errs.DatabaseError, "failed to decrement can_be_used_count", err)
+	}
+
+	return nil
+}
+
 func (r *inviteRepository) DeactivateExpired(ctx context.Context) (int, error) {
 	query := r.qb.Update("invite_codes").
 		Set("is_active", false).

internal/repository/user.go

@@ -86,6 +86,14 @@ func (r *userRepository) FindByID(ctx context.Context, userID int) (*model.User,
 }
 
 func (r *userRepository) Create(ctx context.Context, user *model.User) error {
+	return r.createWithExecutor(ctx, r.pool, user)
+}
+
+func (r *userRepository) CreateTx(ctx context.Context, tx pgx.Tx, user *model.User) error {
+	return r.createWithExecutor(ctx, tx, user)
+}
+
+func (r *userRepository) createWithExecutor(ctx context.Context, exec DBTX, user *model.User) error {
 	encryptedEmail, err := r.cryptoHelper.Encrypt(user.Email)
 	if err != nil {
 		return errs.NewInternalError(errs.EncryptionError, "failed to encrypt email", err)
@@ -114,7 +122,7 @@ func (r *userRepository) Create(ctx context.Context, user *model.User) error {
 		return errs.NewInternalError(errs.DatabaseError, "failed to build query", err)
 	}
 
-	err = r.pool.QueryRow(ctx, sqlQuery, args...).Scan(&user.ID)
+	err = exec.QueryRow(ctx, sqlQuery, args...).Scan(&user.ID)
 	if err != nil {
 		return errs.NewInternalError(errs.DatabaseError, "failed to create user", err)
 	}