package service

import (
	"context"
	"time"

	"git.threesix.ai/jordan/slack5-1770574304/pkg/logging"
	"git.threesix.ai/jordan/slack5-1770574304/services/preferences-api/internal/domain"
	"git.threesix.ai/jordan/slack5-1770574304/services/preferences-api/internal/port"
)

// PreferenceService handles preference-related business logic.
type PreferenceService struct {
	repo   port.PreferenceRepository
	logger *logging.Logger
}

// NewPreferenceService creates a new preference service.
func NewPreferenceService(repo port.PreferenceRepository, logger *logging.Logger) *PreferenceService {
	return &PreferenceService{
		repo:   repo,
		logger: logger.WithService("PreferenceService"),
	}
}

// GetPreferences returns the preferences for a user.
// Returns default preferences if none are stored.
func (s *PreferenceService) GetPreferences(ctx context.Context, userID string) (*domain.UserPreferences, error) {
	prefs, err := s.repo.Get(ctx, userID)
	if err != nil {
		return nil, err
	}
	if prefs == nil {
		return domain.DefaultPreferences(userID), nil
	}
	return prefs, nil
}

// UpdatePreferences validates and persists user preferences.
func (s *PreferenceService) UpdatePreferences(ctx context.Context, userID string, prefs *domain.UserPreferences) (*domain.UserPreferences, error) {
	prefs.UserID = userID
	prefs.UpdatedAt = time.Now().UTC()

	if err := prefs.Validate(); err != nil {
		return nil, err
	}

	if err := s.repo.Upsert(ctx, prefs); err != nil {
		return nil, err
	}

	s.logger.Info("preferences updated", "user_id", userID)

	// Re-fetch to get the DB-set updated_at timestamp
	return s.repo.Get(ctx, userID)
}