package useCases

import (
	"RenewCMS/internal/domain/audit"
	"RenewCMS/internal/domain/user"
	"context"
	"strings"
	"unicode/utf8"
)

const maxDisplayNameRunes = 60

type UpdateUserProfileUseCase struct {
	userRepository user.Repository
	recorder       audit.Recorder
}

func NewUpdateUserProfileUseCase(userRepository user.Repository, recorder audit.Recorder) *UpdateUserProfileUseCase {
	return &UpdateUserProfileUseCase{userRepository, recorder}
}

func (u *UpdateUserProfileUseCase) UpdateDisplayName(ctx context.Context, userId uint32, displayName string) (user.User, error) {
	before, err := u.userRepository.Get(userId)
	if err != nil {
		return user.User{}, err
	}

	event := audit.NewEvent(audit.ActionUserUpdateProfile, audit.CategoryUsers)
	event.Target = userTarget(before)
	trimmed := strings.TrimSpace(displayName)
	if utf8.RuneCountInString(trimmed) > maxDisplayNameRunes {
		recordFailure(ctx, u.recorder, event, user.ErrInvalidDisplayName)
		return user.User{}, user.ErrInvalidDisplayName
	}

	updated, err := u.userRepository.UpdateDisplayName(userId, trimmed)
	if err != nil {
		recordFailure(ctx, u.recorder, event, err)
		return user.User{}, err
	}
	if updated.DisplayName != before.DisplayName {
		event.Target = userTarget(updated)
		event.Changes = []audit.Change{audit.TextChange(audit.FieldDisplayName, before.DisplayName, updated.DisplayName)}
		u.recorder.Record(ctx, event)
	}
	return updated, nil
}

func userTarget(u user.User) audit.Target {
	return audit.NewTarget(audit.TargetUser, u.ID, audit.UserActor(u).Name)
}