package services

import (
	"context"
	"git.aiterp.net/rpdata/api/models"
	"git.aiterp.net/rpdata/api/models/changekeys"
	"git.aiterp.net/rpdata/api/repositories"
	"git.aiterp.net/rpdata/api/services/loaders"
)

// ChannelService is an application service for dealing with channels.
type ChannelService struct {
	channels      repositories.ChannelRepository
	loader        *loaders.ChannelLoader
	changeService *ChangeService
	authService   *AuthService
}

func (s *ChannelService) Find(ctx context.Context, id string) (*models.Channel, error) {
	return s.loader.Load(id)
}

func (s *ChannelService) List(ctx context.Context, filter models.ChannelFilter) ([]*models.Channel, error) {
	if filter.LocationName != nil && filter.EventName != nil && filter.Logged != nil && filter.Limit == 0 && len(filter.Names) > 0 {
		channels, errs := s.loader.LoadAll(filter.Names)
		for _, err := range errs {
			if err != nil && err != repositories.ErrNotFound {
				return nil, err
			}
		}

		output := make([]*models.Channel, 0, len(channels))
		for _, channel := range channels {
			if channel == nil {
				continue
			}
			output = append(output, channel)
		}

		return output, nil
	}

	return s.channels.List(ctx, filter)
}

func (s *ChannelService) Create(ctx context.Context, name string, logged, hub bool, eventName, locationName string) (*models.Channel, error) {
	err := s.authService.CheckPermission(ctx, "add", &models.Channel{})
	if err != nil {
		return nil, err
	}

	channel, err := s.channels.Insert(ctx, models.Channel{
		Name:         name,
		Logged:       logged,
		Hub:          hub,
		EventName:    eventName,
		LocationName: locationName,
	})
	if err != nil {
		return nil, err
	}

	s.changeService.Submit(ctx, "Channel", "add", true, changekeys.Listed(channel), channel)

	return channel, nil
}

func (s *ChannelService) Ensure(ctx context.Context, name string) (*models.Channel, error) {
	channel, err := s.channels.Find(ctx, name)
	if err != nil {
		channel, err = s.channels.Insert(ctx, models.Channel{
			Name:         name,
			Logged:       false,
			Hub:          false,
			EventName:    "",
			LocationName: "",
		})
		if err != nil {
			return nil, err
		}

		s.changeService.Submit(ctx, "Channel", "add", true, changekeys.Listed(channel), channel)
	}

	return channel, nil
}

func (s *ChannelService) Update(ctx context.Context, name string, update models.ChannelUpdate) (*models.Channel, error) {
	channel, err := s.channels.Find(ctx, name)
	if err != nil {
		return nil, err
	}

	err = s.authService.CheckPermission(ctx, "edit", channel)
	if err != nil {
		return nil, err
	}

	channel, err = s.channels.Update(ctx, *channel, update)
	if err != nil {
		return nil, err
	}

	s.loader.Clear(channel.Name)

	s.changeService.Submit(ctx, "Channel", "edit", true, changekeys.Listed(channel), channel)

	return channel, nil
}

func (s *ChannelService) Delete(ctx context.Context, name string) (*models.Channel, error) {
	channel, err := s.channels.Find(ctx, name)
	if err != nil {
		return nil, err
	}

	err = s.authService.CheckPermission(ctx, "remove", channel)
	if err != nil {
		return nil, err
	}

	err = s.channels.Remove(ctx, *channel)
	if err != nil {
		return nil, err
	}

	s.changeService.Submit(ctx, "Channel", "remove", true, changekeys.Listed(channel), channel)

	s.loader.Clear(channel.Name)

	return channel, nil
}