From c684388153f61601ee7cb740a7513d80429c5ec9 Mon Sep 17 00:00:00 2001
From: 77-QiQi <87052253+77-QiQi@users.noreply.github.com>
Date: Tue, 8 Sep 2026 12:07:23 +0800
Subject: [PATCH] Improve: Delete the corresponding DNS record if the IPv4/IPv6
 address is empty.

---
 pkg/ddns/ddns.go | 86 +++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 82 insertions(+), 4 deletions(-)

diff --git a/pkg/ddns/ddns.go b/pkg/ddns/ddns.go
index 7759df54..77779c0b 100644
--- a/pkg/ddns/ddns.go
+++ b/pkg/ddns/ddns.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"net/netip"
+	"strings"
 	"time"
 
 	"github.com/libdns/libdns"
@@ -54,10 +55,13 @@ func (provider *Provider) updateDomain(ctx context.Context, domain string) error
 		return err
 	}
 
-	// 独立处理 IPv4 更新
+	// 独立处理 IPv4 更新或删除
 	if *provider.DDNSProfile.EnableIPv4 {
 		if provider.IPAddrs.IPv4Addr == "" {
-			log.Printf("NEZHA>> Skip IPv4 update for domain %s: IPv4 address is empty", domain)
+			log.Printf("NEZHA>> IPv4 address is empty for domain %s, deleting A record...", domain)
+			if err = provider.deleteDomainRecord(ctx, "A"); err != nil {
+				return fmt.Errorf("failed to delete IPv4 record: %w", err)
+			}
 		} else {
 			if err = provider.addDomainRecord(ctx, "A", provider.IPAddrs.IPv4Addr); err != nil {
 				return err
@@ -65,10 +69,13 @@ func (provider *Provider) updateDomain(ctx context.Context, domain string) error
 		}
 	}
 
-	// 独立处理 IPv6 更新
+	// 独立处理 IPv6 更新或删除
 	if *provider.DDNSProfile.EnableIPv6 {
 		if provider.IPAddrs.IPv6Addr == "" {
-			log.Printf("NEZHA>> Skip IPv6 update for domain %s: IPv6 address is empty", domain)
+			log.Printf("NEZHA>> IPv6 address is empty for domain %s, deleting AAAA record...", domain)
+			if err = provider.deleteDomainRecord(ctx, "AAAA"); err != nil {
+				return fmt.Errorf("failed to delete IPv6 record: %w", err)
+			}
 		} else {
 			if err = provider.addDomainRecord(ctx, "AAAA", provider.IPAddrs.IPv6Addr); err != nil {
 				return err
@@ -96,6 +103,77 @@ func (provider *Provider) addDomainRecord(ctx context.Context, recType, addr str
 	return err
 }
 
+// deleteDomainRecord 用于删除指定类型的解析记录
+func (provider *Provider) deleteDomainRecord(ctx context.Context, recType string) error {
+	// 检查 libdns.RecordGetter 和 libdns.RecordDeleter
+	getter, ok := provider.Setter.(libdns.RecordGetter)
+	if !ok {
+		return fmt.Errorf("dns provider does not support record getting")
+	}
+
+	deleter, ok := provider.Setter.(libdns.RecordDeleter)
+	if !ok {
+		return fmt.Errorf("dns provider does not support record deletion")
+	}
+
+	// 获取 DNS 记录
+	allRecords, err := getter.GetRecords(ctx, provider.zone)
+	if err != nil {
+		return fmt.Errorf("failed to get DNS records: %w", err)
+	}
+
+	cleanName := func(name string) string {
+		return strings.ToLower(strings.TrimSuffix(name, "."))
+	}
+
+	cleanPrefix := cleanName(provider.prefix)
+	cleanZone := cleanName(provider.zone)
+	targetRecType := strings.ToUpper(recType)
+
+	// 筛选和匹配
+	var targetRecords []libdns.Record
+	for _, rec := range allRecords {
+		rr := rec.RR()
+        recName := rr.Name
+        currentType := strings.ToUpper(rr.Type)
+
+		if currentType != targetRecType {
+			continue
+		}
+
+		relName := libdns.RelativeName(recName, provider.zone)
+		cleanRel := cleanName(relName)
+		cleanRRName := cleanName(recName)
+
+		var matchedName bool
+		if cleanPrefix == "" {
+			matchedName = cleanRel == "" || cleanRel == "@" || cleanRRName == cleanZone
+		} else {
+			matchedName = cleanRel == cleanPrefix || cleanRRName == cleanPrefix
+		}
+
+		// 保留原始的 rec 接口（包含 Cloudflare 所需的 ProviderData 元数据），用于精准删除
+		if matchedName {
+			targetRecords = append(targetRecords, rec)
+		}
+	}
+
+	// 若未找到对应记录，则直接返回成功（视为已删除或不存在）
+	if len(targetRecords) == 0 {
+		log.Printf("NEZHA>> No matching %s record found for deletion under zone %s", recType, provider.zone)
+		return nil
+	}
+
+	// 执行删除操作
+	_, err = deleter.DeleteRecords(ctx, provider.zone, targetRecords)
+	if err != nil {
+		return fmt.Errorf("deleter.DeleteRecords failed: %w", err)
+	}
+
+	log.Printf("NEZHA>> Successfully deleted %d matching %s record(s) for %s.%s", len(targetRecords), recType, provider.prefix, provider.zone)
+	return nil
+}
+
 func (provider *Provider) splitDomainSOA(ctx context.Context, domain string) (prefix string, zone string, err error) {
 	c := &dns.Client{Timeout: dnsTimeOut}