package service

import (
	"context"
	"fmt"
	"github.com/grandcat/zeroconf"
	"slices"
	"work_cation/cfg"
	"work_cation/models"
)

type zeroconfService struct {
	server  *zeroconf.Server
	onlines []models.Online
}

var Zeroconf = &zeroconfService{}

// Register 注册被发现服务
func (s *zeroconfService) Register(user *models.Users) error {
	if s.server != nil {
		return nil // already registered
	}
	server, err := zeroconf.Register(cfg.T.ZeroconfKey, "_http._tcp",
		"local.", cfg.T.ZeroconfPort, models.UserTOnlineList(user), nil)
	if err != nil {
		return err
	}
	s.server = server
	return nil
}

func (s *zeroconfService) Close() {
	if s.server != nil {
		s.server.Shutdown()
		s.server = nil
	}
}

// FindService 查找被发现服务
func (s *zeroconfService) FindService() ([]models.Online, error) {
	return s.onlines, nil
}

func (s *zeroconfService) GetOnline(id string) *models.Online {
	for _, online := range s.onlines {
		if online.ID == id {
			return &online
		}
	}
	return nil
}

func (s *zeroconfService) StartFindService() error {
	resolver, err := zeroconf.NewResolver(nil)
	if err != nil {
		return err
	}
	allEntries := make(chan *zeroconf.ServiceEntry)
	go func(results <-chan *zeroconf.ServiceEntry) {
		for entry := range results {
			fmt.Println(entry.AddrIPv4, entry.ServiceInstanceName())
			if entry.ServiceInstanceName() == fmt.Sprintf("%s._http._tcp.local.", cfg.T.ZeroconfKey) {
				online, err := models.NewOnline(entry)
				if err != nil {
					continue
				}
				delOnlines := slices.DeleteFunc(s.onlines, func(item models.Online) bool {
					return item.ID == online.ID
				})
				s.onlines = append(delOnlines, *online)
			}
		}
	}(allEntries)
	err = resolver.Browse(context.Background(), "_http._tcp", "local.", allEntries)
	return err
}