chore: cleanup hostValue code

component/resolver/host.go

@@ -8,7 +8,6 @@ import (
 	"strings"
 	_ "unsafe"
 
-	"github.com/metacubex/mihomo/common/utils"
 	"github.com/metacubex/mihomo/component/resolver/hosts"
 	"github.com/metacubex/mihomo/component/trie"
 	"github.com/metacubex/randv2"
@@ -66,37 +65,35 @@ type HostValue struct {
 	Domain   string
 }
 
-func NewHostValue(value any) (HostValue, error) {
+func NewHostValue(value []string) (HostValue, error) {
 	isDomain := true
-	ips := make([]netip.Addr, 0)
+	ips := make([]netip.Addr, 0, len(value))
 	domain := ""
-	if valueArr, err := utils.ToStringSlice(value); err != nil {
-		return HostValue{}, err
-	} else {
-		if len(valueArr) > 1 {
+	switch len(value) {
+	case 0:
+		return HostValue{}, errors.New("value is empty")
+	case 1:
+		host := value[0]
+		if ip, err := netip.ParseAddr(host); err == nil {
+			ips = append(ips, ip.Unmap())
 			isDomain = false
-			for _, str := range valueArr {
-				if ip, err := netip.ParseAddr(str); err == nil {
-					ips = append(ips, ip.Unmap())
-				} else {
-					return HostValue{}, err
-				}
-			}
-		} else if len(valueArr) == 1 {
-			host := valueArr[0]
-			if ip, err := netip.ParseAddr(host); err == nil {
+		} else {
+			domain = host
+		}
+	default: // > 1
+		isDomain = false
+		for _, str := range value {
+			if ip, err := netip.ParseAddr(str); err == nil {
 				ips = append(ips, ip.Unmap())
-				isDomain = false
 			} else {
-				domain = host
+				return HostValue{}, err
 			}
 		}
 	}
 	if isDomain {
 		return NewHostValueByDomain(domain)
-	} else {
-		return NewHostValueByIPs(ips)
 	}
+	return NewHostValueByIPs(ips)
 }
 
 func NewHostValueByIPs(ips []netip.Addr) (HostValue, error) {

config/config.go

@@ -1115,22 +1115,23 @@ func parseHosts(cfg *RawConfig) (*trie.DomainTrie[resolver.HostValue], error) {
 
 	if len(cfg.Hosts) != 0 {
 		for domain, anyValue := range cfg.Hosts {
-			if str, ok := anyValue.(string); ok && str == "lan" {
+			hosts, err := utils.ToStringSlice(anyValue)
+			if err != nil {
+				return nil, err
+			}
+			if len(hosts) == 1 && hosts[0] == "lan" {
 				if addrs, err := net.InterfaceAddrs(); err != nil {
 					log.Errorln("insert lan to host error: %s", err)
 				} else {
-					ips := make([]netip.Addr, 0)
+					hosts = make([]string, 0, len(addrs))
 					for _, addr := range addrs {
 						if ipnet, ok := addr.(*net.IPNet); ok && !ipnet.IP.IsLoopback() && !ipnet.IP.IsLinkLocalUnicast() {
-							if ip, err := netip.ParseAddr(ipnet.IP.String()); err == nil {
-								ips = append(ips, ip)
-							}
+							hosts = append(hosts, ipnet.IP.String())
 						}
 					}
-					anyValue = ips
 				}
 			}
-			value, err := resolver.NewHostValue(anyValue)
+			value, err := resolver.NewHostValue(hosts)
 			if err != nil {
 				return nil, fmt.Errorf("%s is not a valid value", anyValue)
 			}