package dns

import (
	"net"

	"github.com/Dreamacro/clash/component/trie"
	"github.com/Dreamacro/clash/log"
	"github.com/Dreamacro/clash/rule/geodata"
	"github.com/Dreamacro/clash/rule/geodata/router"
	_ "github.com/Dreamacro/clash/rule/geodata/standard"
)

var geoIPMatcher *router.GeoIPMatcher

type fallbackIPFilter interface {
	Match(net.IP) bool
}

type geoipFilter struct{}

func (gf *geoipFilter) Match(ip net.IP) bool {
	if geoIPMatcher == nil {
		countryCode := "cn"
		geoLoader, err := geodata.GetGeoDataLoader("standard")
		if err != nil {
			log.Errorln("[GeoIPFilter] GetGeoDataLoader error: %s", err.Error())
			return false
		}

		records, err := geoLoader.LoadGeoIP(countryCode)
		if err != nil {
			log.Errorln("[GeoIPFilter] LoadGeoIP error: %s", err.Error())
			return false
		}

		geoIP := &router.GeoIP{
			CountryCode:  countryCode,
			Cidr:         records,
			ReverseMatch: false,
		}

		geoIPMatcher, err = router.NewGeoIPMatcher(geoIP)

		if err != nil {
			log.Errorln("[GeoIPFilter] NewGeoIPMatcher error: %s", err.Error())
			return false
		}
	}

	return !geoIPMatcher.Match(ip)
}

type ipnetFilter struct {
	ipnet *net.IPNet
}

func (inf *ipnetFilter) Match(ip net.IP) bool {
	return inf.ipnet.Contains(ip)
}

type fallbackDomainFilter interface {
	Match(domain string) bool
}
type domainFilter struct {
	tree *trie.DomainTrie
}

func NewDomainFilter(domains []string) *domainFilter {
	df := domainFilter{tree: trie.New()}
	for _, domain := range domains {
		df.tree.Insert(domain, "")
	}
	return &df
}

func (df *domainFilter) Match(domain string) bool {
	return df.tree.Search(domain) != nil
}