package service

import (
	"carrot_bbs/internal/model"
	"carrot_bbs/internal/repository"
)

type ChannelService interface {
	ListActive() ([]*model.Channel, error)
	ListAll() ([]*model.Channel, error)
	MapByIDs(ids []string) (map[string]*model.Channel, error)
	Create(name, slug, description string, sortOrder int, isActive bool) (*model.Channel, error)
	Update(id, name, slug, description string, sortOrder int, isActive bool) (*model.Channel, error)
	Delete(id string) error
}

type channelServiceImpl struct {
	channelRepo *repository.ChannelRepository
}

func NewChannelService(channelRepo *repository.ChannelRepository) ChannelService {
	return &channelServiceImpl{channelRepo: channelRepo}
}

func (s *channelServiceImpl) ListActive() ([]*model.Channel, error) {
	return s.channelRepo.ListActive()
}

func (s *channelServiceImpl) ListAll() ([]*model.Channel, error) {
	return s.channelRepo.ListAll()
}

func (s *channelServiceImpl) MapByIDs(ids []string) (map[string]*model.Channel, error) {
	list, err := s.channelRepo.ListByIDs(ids)
	if err != nil {
		return nil, err
	}
	m := make(map[string]*model.Channel, len(list))
	for _, ch := range list {
		if ch != nil {
			m[ch.ID] = ch
		}
	}
	return m, nil
}

func (s *channelServiceImpl) Create(name, slug, description string, sortOrder int, isActive bool) (*model.Channel, error) {
	channel := &model.Channel{
		Name:        name,
		Slug:        slug,
		Description: description,
		SortOrder:   sortOrder,
		IsActive:    isActive,
	}
	if err := s.channelRepo.Create(channel); err != nil {
		return nil, err
	}
	return channel, nil
}

func (s *channelServiceImpl) Update(id, name, slug, description string, sortOrder int, isActive bool) (*model.Channel, error) {
	channel, err := s.channelRepo.GetByID(id)
	if err != nil {
		return nil, err
	}
	channel.Name = name
	channel.Slug = slug
	channel.Description = description
	channel.SortOrder = sortOrder
	channel.IsActive = isActive
	if err := s.channelRepo.Update(channel); err != nil {
		return nil, err
	}
	return channel, nil
}

func (s *channelServiceImpl) Delete(id string) error {
	return s.channelRepo.Delete(id)
}