using System.Collections.Generic;
using System.Data;
using System.Net;
using System.Net.NetworkInformation;
using System.Reactive;
using System.Text;
using DynamicData;
using ServiceLib.Models;

namespace ServiceLib.Services.CoreConfig;

public class CoreConfigSingboxService
{
    private Config _config;
    private static readonly string _tag = "CoreConfigSingboxService";

    public CoreConfigSingboxService(Config config)
    {
        _config = config;
    }

    #region public gen function

    public async Task<RetResult> GenerateClientConfigContent(ProfileItem node)
    {
        var ret = new RetResult();
        try
        {
            if (node == null
                || node.Port <= 0)
            {
                ret.Msg = ResUI.CheckServerSettings;
                return ret;
            }
            if (node.GetNetwork() is nameof(ETransport.kcp) or nameof(ETransport.xhttp))
            {
                ret.Msg = ResUI.Incorrectconfiguration + $" - {node.GetNetwork()}";
                return ret;
            }

            ret.Msg = ResUI.InitialConfiguration;

            string result = EmbedUtils.GetEmbedText(Global.SingboxSampleClient);
            if (result.IsNullOrEmpty())
            {
                ret.Msg = ResUI.FailedGetDefaultConfiguration;
                return ret;
            }

            var singboxConfig = JsonUtils.Deserialize<SingboxConfig>(result);
            if (singboxConfig == null)
            {
                ret.Msg = ResUI.FailedGenDefaultConfiguration;
                return ret;
            }

            await GenLog(singboxConfig);

            await GenInbounds(singboxConfig);

            if (node.ConfigType == EConfigType.WireGuard)
            {
                singboxConfig.outbounds.RemoveAt(0);
                var endpoints = new Endpoints4Sbox();
                await GenEndpoint(node, endpoints);
                endpoints.tag = Global.ProxyTag;
                singboxConfig.endpoints = new() { endpoints };
            }
            else
            {
                await GenOutbound(node, singboxConfig.outbounds.First());
            }

            await GenMoreOutbounds(node, singboxConfig);

            await GenRouting(singboxConfig);

            await GenDns(singboxConfig);

            await GenExperimental(singboxConfig);

            await ConvertGeo2Ruleset(singboxConfig);

            ret.Msg = string.Format(ResUI.SuccessfulConfiguration, "");
            ret.Success = true;
            ret.Data = JsonUtils.Serialize(singboxConfig);
            return ret;
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
            ret.Msg = ResUI.FailedGenDefaultConfiguration;
            return ret;
        }
    }

    public async Task<RetResult> GenerateClientSpeedtestConfig(List<ServerTestItem> selecteds)
    {
        var ret = new RetResult();
        try
        {
            if (_config == null)
            {
                ret.Msg = ResUI.CheckServerSettings;
                return ret;
            }

            ret.Msg = ResUI.InitialConfiguration;

            var result = EmbedUtils.GetEmbedText(Global.SingboxSampleClient);
            var txtOutbound = EmbedUtils.GetEmbedText(Global.SingboxSampleOutbound);
            if (result.IsNullOrEmpty() || txtOutbound.IsNullOrEmpty())
            {
                ret.Msg = ResUI.FailedGetDefaultConfiguration;
                return ret;
            }

            var singboxConfig = JsonUtils.Deserialize<SingboxConfig>(result);
            if (singboxConfig == null)
            {
                ret.Msg = ResUI.FailedGenDefaultConfiguration;
                return ret;
            }
            List<IPEndPoint> lstIpEndPoints = new();
            List<TcpConnectionInformation> lstTcpConns = new();
            try
            {
                lstIpEndPoints.AddRange(IPGlobalProperties.GetIPGlobalProperties().GetActiveTcpListeners());
                lstIpEndPoints.AddRange(IPGlobalProperties.GetIPGlobalProperties().GetActiveUdpListeners());
                lstTcpConns.AddRange(IPGlobalProperties.GetIPGlobalProperties().GetActiveTcpConnections());
            }
            catch (Exception ex)
            {
                Logging.SaveLog(_tag, ex);
            }

            await GenLog(singboxConfig);
            //GenDns(new(), singboxConfig);
            singboxConfig.inbounds.Clear();
            singboxConfig.outbounds.RemoveAt(0);

            var initPort = AppHandler.Instance.GetLocalPort(EInboundProtocol.speedtest);

            foreach (var it in selecteds)
            {
                if (it.ConfigType == EConfigType.Custom)
                {
                    continue;
                }
                if (it.Port <= 0)
                {
                    continue;
                }
                var item = await AppHandler.Instance.GetProfileItem(it.IndexId);
                if (it.ConfigType is EConfigType.VMess or EConfigType.VLESS)
                {
                    if (item is null || item.Id.IsNullOrEmpty() || !Utils.IsGuidByParse(item.Id))
                    {
                        continue;
                    }
                }

                //find unused port
                var port = initPort;
                for (int k = initPort; k < Global.MaxPort; k++)
                {
                    if (lstIpEndPoints?.FindIndex(_it => _it.Port == k) >= 0)
                    {
                        continue;
                    }
                    if (lstTcpConns?.FindIndex(_it => _it.LocalEndPoint.Port == k) >= 0)
                    {
                        continue;
                    }
                    //found
                    port = k;
                    initPort = port + 1;
                    break;
                }

                //Port In Used
                if (lstIpEndPoints?.FindIndex(_it => _it.Port == port) >= 0)
                {
                    continue;
                }
                it.Port = port;
                it.AllowTest = true;

                //inbound
                Inbound4Sbox inbound = new()
                {
                    listen = Global.Loopback,
                    listen_port = port,
                    type = EInboundProtocol.mixed.ToString(),
                };
                inbound.tag = inbound.type + inbound.listen_port.ToString();
                singboxConfig.inbounds.Add(inbound);

                //outbound
                if (item is null)
                {
                    continue;
                }
                if (item.ConfigType == EConfigType.Shadowsocks
                    && !Global.SsSecuritiesInSingbox.Contains(item.Security))
                {
                    continue;
                }
                if (item.ConfigType == EConfigType.VLESS
                 && !Global.Flows.Contains(item.Flow))
                {
                    continue;
                }
                if (it.ConfigType is EConfigType.VLESS or EConfigType.Trojan
                    && item.StreamSecurity == Global.StreamSecurityReality
                    && item.PublicKey.IsNullOrEmpty())
                {
                    continue;
                }

                var server = await GenServer(item);
                if (server is null)
                {
                    ret.Msg = ResUI.FailedGenDefaultConfiguration;
                    return ret;
                }
                var tag = Global.ProxyTag + inbound.listen_port.ToString();
                server.tag = tag;
                if (server is Endpoints4Sbox endpoint)
                {
                    singboxConfig.endpoints ??= new();
                    singboxConfig.endpoints.Add(endpoint);
                }
                else if (server is Outbound4Sbox outbound)
                {
                    singboxConfig.outbounds.Add(outbound);
                }

                //rule
                Rule4Sbox rule = new()
                {
                    inbound = new List<string> { inbound.tag },
                    outbound = tag
                };
                singboxConfig.route.rules.Add(rule);
            }

            await GenDnsDomains(singboxConfig, _config.DNSItem);
            //var dnsServer = singboxConfig.dns?.servers.FirstOrDefault();
            //if (dnsServer != null)
            //{
            //    dnsServer.detour = singboxConfig.route.rules.LastOrDefault()?.outbound;
            //}
            //var dnsRule = singboxConfig.dns?.rules.Where(t => t.outbound != null).FirstOrDefault();
            //if (dnsRule != null)
            //{
            //    singboxConfig.dns.rules = [];
            //    singboxConfig.dns.rules.Add(dnsRule);
            //}

            //ret.Msg =string.Format(ResUI.SuccessfulConfiguration"), node.getSummary());
            ret.Success = true;
            ret.Data = JsonUtils.Serialize(singboxConfig);
            return ret;
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
            ret.Msg = ResUI.FailedGenDefaultConfiguration;
            return ret;
        }
    }

    public async Task<RetResult> GenerateClientSpeedtestConfig(ProfileItem node, int port)
    {
        var ret = new RetResult();
        try
        {
            if (node is not { Port: > 0 })
            {
                ret.Msg = ResUI.CheckServerSettings;
                return ret;
            }
            if (node.GetNetwork() is nameof(ETransport.kcp) or nameof(ETransport.xhttp))
            {
                ret.Msg = ResUI.Incorrectconfiguration + $" - {node.GetNetwork()}";
                return ret;
            }

            ret.Msg = ResUI.InitialConfiguration;

            var result = EmbedUtils.GetEmbedText(Global.SingboxSampleClient);
            if (result.IsNullOrEmpty())
            {
                ret.Msg = ResUI.FailedGetDefaultConfiguration;
                return ret;
            }

            var singboxConfig = JsonUtils.Deserialize<SingboxConfig>(result);
            if (singboxConfig == null)
            {
                ret.Msg = ResUI.FailedGenDefaultConfiguration;
                return ret;
            }

            await GenLog(singboxConfig);
            if (node.ConfigType == EConfigType.WireGuard)
            {
                singboxConfig.outbounds.RemoveAt(0);
                var endpoints = new Endpoints4Sbox();
                await GenEndpoint(node, endpoints);
                endpoints.tag = Global.ProxyTag;
                singboxConfig.endpoints = new() { endpoints };
            }
            else
            {
                await GenOutbound(node, singboxConfig.outbounds.First());
            }
            await GenMoreOutbounds(node, singboxConfig);
            await GenDnsDomains(singboxConfig, _config.DNSItem);

            singboxConfig.route.rules.Clear();
            singboxConfig.inbounds.Clear();
            singboxConfig.inbounds.Add(new()
            {
                tag = $"{EInboundProtocol.mixed}{port}",
                listen = Global.Loopback,
                listen_port = port,
                type = EInboundProtocol.mixed.ToString(),
            });

            ret.Msg = string.Format(ResUI.SuccessfulConfiguration, "");
            ret.Success = true;
            ret.Data = JsonUtils.Serialize(singboxConfig);
            return ret;
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
            ret.Msg = ResUI.FailedGenDefaultConfiguration;
            return ret;
        }
    }

    public async Task<RetResult> GenerateClientMultipleLoadConfig(List<ProfileItem> selecteds)
    {
        var ret = new RetResult();
        try
        {
            if (_config == null)
            {
                ret.Msg = ResUI.CheckServerSettings;
                return ret;
            }

            ret.Msg = ResUI.InitialConfiguration;

            string result = EmbedUtils.GetEmbedText(Global.SingboxSampleClient);
            string txtOutbound = EmbedUtils.GetEmbedText(Global.SingboxSampleOutbound);
            if (result.IsNullOrEmpty() || txtOutbound.IsNullOrEmpty())
            {
                ret.Msg = ResUI.FailedGetDefaultConfiguration;
                return ret;
            }

            var singboxConfig = JsonUtils.Deserialize<SingboxConfig>(result);
            if (singboxConfig == null)
            {
                ret.Msg = ResUI.FailedGenDefaultConfiguration;
                return ret;
            }

            await GenLog(singboxConfig);
            await GenInbounds(singboxConfig);
            await GenRouting(singboxConfig);
            await GenExperimental(singboxConfig);
            singboxConfig.outbounds.RemoveAt(0);

            var proxyProfiles = new List<ProfileItem>();
            foreach (var it in selecteds)
            {
                if (it.ConfigType == EConfigType.Custom)
                {
                    continue;
                }
                if (it.Port <= 0)
                {
                    continue;
                }
                var item = await AppHandler.Instance.GetProfileItem(it.IndexId);
                if (item is null)
                {
                    continue;
                }
                if (it.ConfigType is EConfigType.VMess or EConfigType.VLESS)
                {
                    if (item.Id.IsNullOrEmpty() || !Utils.IsGuidByParse(item.Id))
                    {
                        continue;
                    }
                }
                if (item.ConfigType == EConfigType.Shadowsocks
                  && !Global.SsSecuritiesInSingbox.Contains(item.Security))
                {
                    continue;
                }
                if (item.ConfigType == EConfigType.VLESS && !Global.Flows.Contains(item.Flow))
                {
                    continue;
                }

                //outbound
                proxyProfiles.Add(item);
            }
            if (proxyProfiles.Count <= 0)
            {
                ret.Msg = ResUI.FailedGenDefaultConfiguration;
                return ret;
            }
            await GenOutboundsList(proxyProfiles, singboxConfig);

            await GenDns(singboxConfig);
            await ConvertGeo2Ruleset(singboxConfig);

            ret.Success = true;
            ret.Data = JsonUtils.Serialize(singboxConfig);
            return ret;
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
            ret.Msg = ResUI.FailedGenDefaultConfiguration;
            return ret;
        }
    }

    public async Task<RetResult> GenerateClientCustomConfig(ProfileItem node, string? fileName)
    {
        var ret = new RetResult();
        if (node == null || fileName is null)
        {
            ret.Msg = ResUI.CheckServerSettings;
            return ret;
        }

        ret.Msg = ResUI.InitialConfiguration;

        try
        {
            if (node == null)
            {
                ret.Msg = ResUI.CheckServerSettings;
                return ret;
            }

            if (File.Exists(fileName))
            {
                File.Delete(fileName);
            }

            string addressFileName = node.Address;
            if (addressFileName.IsNullOrEmpty())
            {
                ret.Msg = ResUI.FailedGetDefaultConfiguration;
                return ret;
            }
            if (!File.Exists(addressFileName))
            {
                addressFileName = Path.Combine(Utils.GetConfigPath(), addressFileName);
            }
            if (!File.Exists(addressFileName))
            {
                ret.Msg = ResUI.FailedReadConfiguration + "1";
                return ret;
            }

            if (node.Address == Global.CoreMultipleLoadConfigFileName)
            {
                var txtFile = File.ReadAllText(addressFileName);
                var singboxConfig = JsonUtils.Deserialize<SingboxConfig>(txtFile);
                if (singboxConfig == null)
                {
                    File.Copy(addressFileName, fileName);
                }
                else
                {
                    await GenInbounds(singboxConfig);
                    await GenExperimental(singboxConfig);

                    var content = JsonUtils.Serialize(singboxConfig, true);
                    await File.WriteAllTextAsync(fileName, content);
                }
            }
            else
            {
                File.Copy(addressFileName, fileName);
            }

            //check again
            if (!File.Exists(fileName))
            {
                ret.Msg = ResUI.FailedReadConfiguration + "2";
                return ret;
            }

            ret.Msg = string.Format(ResUI.SuccessfulConfiguration, "");
            ret.Success = true;
            return ret;
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
            ret.Msg = ResUI.FailedGenDefaultConfiguration;
            return ret;
        }
    }

    #endregion public gen function

    #region private gen function

    private async Task<int> GenLog(SingboxConfig singboxConfig)
    {
        try
        {
            switch (_config.CoreBasicItem.Loglevel)
            {
                case "debug":
                case "info":
                case "error":
                    singboxConfig.log.level = _config.CoreBasicItem.Loglevel;
                    break;

                case "warning":
                    singboxConfig.log.level = "warn";
                    break;

                default:
                    break;
            }
            if (_config.CoreBasicItem.Loglevel == Global.None)
            {
                singboxConfig.log.disabled = true;
            }
            if (_config.CoreBasicItem.LogEnabled)
            {
                var dtNow = DateTime.Now;
                singboxConfig.log.output = Utils.GetLogPath($"sbox_{dtNow:yyyy-MM-dd}.txt");
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return await Task.FromResult(0);
    }

    private async Task<int> GenInbounds(SingboxConfig singboxConfig)
    {
        try
        {
            var listen = "0.0.0.0";
            singboxConfig.inbounds = [];

            if (!_config.TunModeItem.EnableTun
                || (_config.TunModeItem.EnableTun && _config.TunModeItem.EnableExInbound && _config.RunningCoreType == ECoreType.sing_box))
            {
                var inbound = new Inbound4Sbox()
                {
                    type = EInboundProtocol.mixed.ToString(),
                    tag = EInboundProtocol.socks.ToString(),
                    listen = Global.Loopback,
                };
                singboxConfig.inbounds.Add(inbound);

                inbound.listen_port = AppHandler.Instance.GetLocalPort(EInboundProtocol.socks);

                if (_config.Inbound.First().SecondLocalPortEnabled)
                {
                    var inbound2 = GetInbound(inbound, EInboundProtocol.socks2, true);
                    singboxConfig.inbounds.Add(inbound2);
                }

                if (_config.Inbound.First().AllowLANConn)
                {
                    if (_config.Inbound.First().NewPort4LAN)
                    {
                        var inbound3 = GetInbound(inbound, EInboundProtocol.socks3, true);
                        inbound3.listen = listen;
                        singboxConfig.inbounds.Add(inbound3);

                        //auth
                        if (_config.Inbound.First().User.IsNotEmpty() && _config.Inbound.First().Pass.IsNotEmpty())
                        {
                            inbound3.users = new() { new() { username = _config.Inbound.First().User, password = _config.Inbound.First().Pass } };
                        }
                    }
                    else
                    {
                        inbound.listen = listen;
                    }
                }
            }

            if (_config.TunModeItem.EnableTun)
            {
                if (_config.TunModeItem.Mtu <= 0)
                {
                    _config.TunModeItem.Mtu = Global.TunMtus.First();
                }
                if (_config.TunModeItem.Stack.IsNullOrEmpty())
                {
                    _config.TunModeItem.Stack = Global.TunStacks.First();
                }

                var tunInbound = JsonUtils.Deserialize<Inbound4Sbox>(EmbedUtils.GetEmbedText(Global.TunSingboxInboundFileName)) ?? new Inbound4Sbox { };
                tunInbound.interface_name = Utils.IsOSX() ? $"utun{new Random().Next(99)}" : "singbox_tun";
                tunInbound.mtu = _config.TunModeItem.Mtu;
                tunInbound.strict_route = _config.TunModeItem.StrictRoute;
                tunInbound.stack = _config.TunModeItem.Stack;
                if (_config.TunModeItem.EnableIPv6Address == false)
                {
                    tunInbound.address = ["172.18.0.1/30"];
                }

                singboxConfig.inbounds.Add(tunInbound);
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return 0;
    }

    private Inbound4Sbox GetInbound(Inbound4Sbox inItem, EInboundProtocol protocol, bool bSocks)
    {
        var inbound = JsonUtils.DeepCopy(inItem);
        inbound.tag = protocol.ToString();
        inbound.listen_port = inItem.listen_port + (int)protocol;
        inbound.type = EInboundProtocol.mixed.ToString();
        return inbound;
    }

    private async Task<int> GenOutbound(ProfileItem node, Outbound4Sbox outbound)
    {
        try
        {
            outbound.server = node.Address;
            outbound.server_port = node.Port;
            outbound.type = Global.ProtocolTypes[node.ConfigType];

            switch (node.ConfigType)
            {
                case EConfigType.VMess:
                    {
                        outbound.uuid = node.Id;
                        outbound.alter_id = node.AlterId;
                        if (Global.VmessSecurities.Contains(node.Security))
                        {
                            outbound.security = node.Security;
                        }
                        else
                        {
                            outbound.security = Global.DefaultSecurity;
                        }

                        await GenOutboundMux(node, outbound);
                        break;
                    }
                case EConfigType.Shadowsocks:
                    {
                        outbound.method = AppHandler.Instance.GetShadowsocksSecurities(node).Contains(node.Security) ? node.Security : Global.None;
                        outbound.password = node.Id;

                        await GenOutboundMux(node, outbound);
                        break;
                    }
                case EConfigType.SOCKS:
                    {
                        outbound.version = "5";
                        if (node.Security.IsNotEmpty()
                          && node.Id.IsNotEmpty())
                        {
                            outbound.username = node.Security;
                            outbound.password = node.Id;
                        }
                        break;
                    }
                case EConfigType.HTTP:
                    {
                        if (node.Security.IsNotEmpty()
                          && node.Id.IsNotEmpty())
                        {
                            outbound.username = node.Security;
                            outbound.password = node.Id;
                        }
                        break;
                    }
                case EConfigType.VLESS:
                    {
                        outbound.uuid = node.Id;

                        outbound.packet_encoding = "xudp";

                        if (node.Flow.IsNullOrEmpty())
                        {
                            await GenOutboundMux(node, outbound);
                        }
                        else
                        {
                            outbound.flow = node.Flow;
                        }
                        break;
                    }
                case EConfigType.Trojan:
                    {
                        outbound.password = node.Id;

                        await GenOutboundMux(node, outbound);
                        break;
                    }
                case EConfigType.Hysteria2:
                    {
                        outbound.password = node.Id;

                        if (node.Path.IsNotEmpty())
                        {
                            outbound.obfs = new()
                            {
                                type = "salamander",
                                password = node.Path.TrimEx(),
                            };
                        }

                        outbound.up_mbps = _config.HysteriaItem.UpMbps > 0 ? _config.HysteriaItem.UpMbps : null;
                        outbound.down_mbps = _config.HysteriaItem.DownMbps > 0 ? _config.HysteriaItem.DownMbps : null;
                        if (node.Ports.IsNotEmpty() && (node.Ports.Contains(':') || node.Ports.Contains('-') || node.Ports.Contains(',')))
                        {
                            outbound.server_port = null;
                            outbound.server_ports = node.Ports.Split(',')
                                .Select(p => p.Trim())
                                .Where(p => p.IsNotEmpty())
                                .Select(p =>
                                {
                                    var port = p.Replace('-', ':');
                                    return port.Contains(':') ? port : $"{port}:{port}";
                                })
                                .ToList();
                            outbound.hop_interval = _config.HysteriaItem.HopInterval > 0 ? $"{_config.HysteriaItem.HopInterval}s" : null;
                        }

                        break;
                    }
                case EConfigType.TUIC:
                    {
                        outbound.uuid = node.Id;
                        outbound.password = node.Security;
                        outbound.congestion_control = node.HeaderType;
                        break;
                    }
                case EConfigType.Anytls:
                    {
                        outbound.password = node.Id;
                        break;
                    }
            }

            await GenOutboundTls(node, outbound);

            await GenOutboundTransport(node, outbound);
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return 0;
    }

    private async Task<int> GenEndpoint(ProfileItem node, Endpoints4Sbox endpoint)
    {
        try
        {
            endpoint.address = Utils.String2List(node.RequestHost);
            endpoint.type = Global.ProtocolTypes[node.ConfigType];

            switch (node.ConfigType)
            {
                case EConfigType.WireGuard:
                    {
                        var peer = new Peer4Sbox
                        {
                            public_key = node.PublicKey,
                            reserved = Utils.String2List(node.Path)?.Select(int.Parse).ToList(),
                            address = node.Address,
                            port = node.Port,
                            // TODO default ["0.0.0.0/0", "::/0"]
                            allowed_ips = new() { "0.0.0.0/0", "::/0" },
                        };
                        endpoint.private_key = node.Id;
                        endpoint.mtu = node.ShortId.IsNullOrEmpty() ? Global.TunMtus.First() : node.ShortId.ToInt();
                        endpoint.peers = new() { peer };
                        break;
                    }
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return await Task.FromResult(0);
    }

    private async Task<BaseServer4Sbox?> GenServer(ProfileItem node)
    {
        try
        {
            var txtOutbound = EmbedUtils.GetEmbedText(Global.SingboxSampleOutbound);
            if (node.ConfigType == EConfigType.WireGuard)
            {
                var endpoint = JsonUtils.Deserialize<Endpoints4Sbox>(txtOutbound);
                await GenEndpoint(node, endpoint);
                return endpoint;
            }
            else
            {
                var outbound = JsonUtils.Deserialize<Outbound4Sbox>(txtOutbound);
                await GenOutbound(node, outbound);
                return outbound;
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return await Task.FromResult<BaseServer4Sbox?>(null);
    }

    private async Task<int> GenOutboundMux(ProfileItem node, Outbound4Sbox outbound)
    {
        try
        {
            var muxEnabled = node.MuxEnabled ?? _config.CoreBasicItem.MuxEnabled;
            if (muxEnabled && _config.Mux4SboxItem.Protocol.IsNotEmpty())
            {
                var mux = new Multiplex4Sbox()
                {
                    enabled = true,
                    protocol = _config.Mux4SboxItem.Protocol,
                    max_connections = _config.Mux4SboxItem.MaxConnections,
                    padding = _config.Mux4SboxItem.Padding,
                };
                outbound.multiplex = mux;
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return await Task.FromResult(0);
    }

    private async Task<int> GenOutboundTls(ProfileItem node, Outbound4Sbox outbound)
    {
        try
        {
            if (node.StreamSecurity == Global.StreamSecurityReality || node.StreamSecurity == Global.StreamSecurity)
            {
                var server_name = string.Empty;
                if (node.Sni.IsNotEmpty())
                {
                    server_name = node.Sni;
                }
                else if (node.RequestHost.IsNotEmpty())
                {
                    server_name = Utils.String2List(node.RequestHost)?.First();
                }
                var tls = new Tls4Sbox()
                {
                    enabled = true,
                    server_name = server_name,
                    insecure = Utils.ToBool(node.AllowInsecure.IsNullOrEmpty() ? _config.CoreBasicItem.DefAllowInsecure.ToString().ToLower() : node.AllowInsecure),
                    alpn = node.GetAlpn(),
                };
                if (node.Fingerprint.IsNotEmpty())
                {
                    tls.utls = new Utls4Sbox()
                    {
                        enabled = true,
                        fingerprint = node.Fingerprint.IsNullOrEmpty() ? _config.CoreBasicItem.DefFingerprint : node.Fingerprint
                    };
                }
                if (node.StreamSecurity == Global.StreamSecurityReality)
                {
                    tls.reality = new Reality4Sbox()
                    {
                        enabled = true,
                        public_key = node.PublicKey,
                        short_id = node.ShortId
                    };
                    tls.insecure = false;
                }
                outbound.tls = tls;
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return await Task.FromResult(0);
    }

    private async Task<int> GenOutboundTransport(ProfileItem node, Outbound4Sbox outbound)
    {
        try
        {
            var transport = new Transport4Sbox();

            switch (node.GetNetwork())
            {
                case nameof(ETransport.h2):
                    transport.type = nameof(ETransport.http);
                    transport.host = node.RequestHost.IsNullOrEmpty() ? null : Utils.String2List(node.RequestHost);
                    transport.path = node.Path.IsNullOrEmpty() ? null : node.Path;
                    break;

                case nameof(ETransport.tcp):   //http
                    if (node.HeaderType == Global.TcpHeaderHttp)
                    {
                        if (node.ConfigType == EConfigType.Shadowsocks)
                        {
                            outbound.plugin = "obfs-local";
                            outbound.plugin_opts = $"obfs=http;obfs-host={node.RequestHost};";
                        }
                        else
                        {
                            transport.type = nameof(ETransport.http);
                            transport.host = node.RequestHost.IsNullOrEmpty() ? null : Utils.String2List(node.RequestHost);
                            transport.path = node.Path.IsNullOrEmpty() ? null : node.Path;
                        }
                    }
                    break;

                case nameof(ETransport.ws):
                    transport.type = nameof(ETransport.ws);
                    transport.path = node.Path.IsNullOrEmpty() ? null : node.Path;
                    if (node.RequestHost.IsNotEmpty())
                    {
                        transport.headers = new()
                        {
                            Host = node.RequestHost
                        };
                    }
                    break;

                case nameof(ETransport.httpupgrade):
                    transport.type = nameof(ETransport.httpupgrade);
                    transport.path = node.Path.IsNullOrEmpty() ? null : node.Path;
                    transport.host = node.RequestHost.IsNullOrEmpty() ? null : node.RequestHost;

                    break;

                case nameof(ETransport.quic):
                    transport.type = nameof(ETransport.quic);
                    break;

                case nameof(ETransport.grpc):
                    transport.type = nameof(ETransport.grpc);
                    transport.service_name = node.Path;
                    transport.idle_timeout = _config.GrpcItem.IdleTimeout?.ToString("##s");
                    transport.ping_timeout = _config.GrpcItem.HealthCheckTimeout?.ToString("##s");
                    transport.permit_without_stream = _config.GrpcItem.PermitWithoutStream;
                    break;

                default:
                    break;
            }
            if (transport.type != null)
            {
                outbound.transport = transport;
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return await Task.FromResult(0);
    }

    private async Task<int> GenMoreOutbounds(ProfileItem node, SingboxConfig singboxConfig)
    {
        if (node.Subid.IsNullOrEmpty())
        {
            return 0;
        }
        try
        {
            var subItem = await AppHandler.Instance.GetSubItem(node.Subid);
            if (subItem is null)
            {
                return 0;
            }

            //current proxy
            BaseServer4Sbox? outbound = singboxConfig.endpoints?.FirstOrDefault(t => t.tag == Global.ProxyTag) == null ? singboxConfig.outbounds.First() : null;

            var txtOutbound = EmbedUtils.GetEmbedText(Global.SingboxSampleOutbound);

            //Previous proxy
            var prevNode = await AppHandler.Instance.GetProfileItemViaRemarks(subItem.PrevProfile);
            string? prevOutboundTag = null;
            if (prevNode is not null
                && prevNode.ConfigType != EConfigType.Custom)
            {
                prevOutboundTag = $"prev-{Global.ProxyTag}";
                var prevServer = await GenServer(prevNode);
                prevServer.tag = prevOutboundTag;
                if (prevServer is Endpoints4Sbox endpoint)
                {
                    singboxConfig.endpoints ??= new();
                    singboxConfig.endpoints.Add(endpoint);
                }
                else if (prevServer is Outbound4Sbox outboundPrev)
                {
                    singboxConfig.outbounds.Add(outboundPrev);
                }
            }
            var nextServer = await GenChainOutbounds(subItem, outbound, prevOutboundTag);

            if (nextServer is not null)
            {
                if (nextServer is Endpoints4Sbox endpoint)
                {
                    singboxConfig.endpoints ??= new();
                    singboxConfig.endpoints.Insert(0, endpoint);
                }
                else if (nextServer is Outbound4Sbox outboundNext)
                {
                    singboxConfig.outbounds.Insert(0, outboundNext);
                }
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }

        return 0;
    }

    private async Task<int> GenOutboundsList(List<ProfileItem> nodes, SingboxConfig singboxConfig)
    {
        try
        {
            // Get outbound template and initialize lists
            var txtOutbound = EmbedUtils.GetEmbedText(Global.SingboxSampleOutbound);
            if (txtOutbound.IsNullOrEmpty())
            {
                return 0;
            }

            var resultOutbounds = new List<Outbound4Sbox>();
            var resultEndpoints = new List<Endpoints4Sbox>(); // For endpoints
            var prevOutbounds = new List<Outbound4Sbox>(); // Separate list for prev outbounds
            var prevEndpoints = new List<Endpoints4Sbox>(); // Separate list for prev endpoints
            var proxyTags = new List<string>(); // For selector and urltest outbounds

            // Cache for chain proxies to avoid duplicate generation
            var nextProxyCache = new Dictionary<string, BaseServer4Sbox?>();
            var prevProxyTags = new Dictionary<string, string?>(); // Map from profile name to tag
            int prevIndex = 0; // Index for prev outbounds

            // Process each node
            int index = 0;
            foreach (var node in nodes)
            {
                index++;

                // Handle proxy chain
                string? prevTag = null;
                var currentServer = await GenServer(node);
                var nextServer = nextProxyCache.GetValueOrDefault(node.Subid, null);
                if (nextServer != null)
                {
                    nextServer = JsonUtils.DeepCopy(nextServer);
                }

                var subItem = await AppHandler.Instance.GetSubItem(node.Subid);

                // current proxy
                currentServer.tag = $"{Global.ProxyTag}-{index}";
                proxyTags.Add(currentServer.tag);

                if (!node.Subid.IsNullOrEmpty())
                {
                    if (prevProxyTags.TryGetValue(node.Subid, out var value))
                    {
                        prevTag = value; // maybe null
                    }
                    else
                    {
                        var prevNode = await AppHandler.Instance.GetProfileItemViaRemarks(subItem.PrevProfile);
                        if (prevNode is not null
                            && prevNode.ConfigType != EConfigType.Custom)
                        {
                            var prevOutbound = JsonUtils.Deserialize<Outbound4Sbox>(txtOutbound);
                            await GenOutbound(prevNode, prevOutbound);
                            prevTag = $"prev-{Global.ProxyTag}-{++prevIndex}";
                            prevOutbound.tag = prevTag;
                            prevOutbounds.Add(prevOutbound);
                        }
                        prevProxyTags[node.Subid] = prevTag;
                    }

                    nextServer = await GenChainOutbounds(subItem, currentServer, prevTag, nextServer);
                    if (!nextProxyCache.ContainsKey(node.Subid))
                    {
                        nextProxyCache[node.Subid] = nextServer;
                    }
                }

                if (nextServer is not null)
                {
                    if (nextServer is Endpoints4Sbox nextEndpoint)
                    {
                        resultEndpoints.Add(nextEndpoint);
                    }
                    else if (nextServer is Outbound4Sbox nextOutbound)
                    {
                        resultOutbounds.Add(nextOutbound);
                    }
                }
                if (currentServer is Endpoints4Sbox currentEndpoint)
                {
                    resultEndpoints.Add(currentEndpoint);
                }
                else if (currentServer is Outbound4Sbox currentOutbound)
                {
                    resultOutbounds.Add(currentOutbound);
                }
            }

            // Add urltest outbound (auto selection based on latency)
            if (proxyTags.Count > 0)
            {
                var outUrltest = new Outbound4Sbox
                {
                    type = "urltest",
                    tag = $"{Global.ProxyTag}-auto",
                    outbounds = proxyTags,
                    interrupt_exist_connections = false,
                };

                // Add selector outbound (manual selection)
                var outSelector = new Outbound4Sbox
                {
                    type = "selector",
                    tag = Global.ProxyTag,
                    outbounds = JsonUtils.DeepCopy(proxyTags),
                    interrupt_exist_connections = false,
                };
                outSelector.outbounds.Insert(0, outUrltest.tag);

                // Insert these at the beginning
                resultOutbounds.Insert(0, outUrltest);
                resultOutbounds.Insert(0, outSelector);
            }

            // Merge results: first the selector/urltest/proxies, then other outbounds, and finally prev outbounds
            resultOutbounds.AddRange(prevOutbounds);
            resultOutbounds.AddRange(singboxConfig.outbounds);
            singboxConfig.outbounds = resultOutbounds;
            singboxConfig.endpoints ??= new List<Endpoints4Sbox>();
            resultEndpoints.AddRange(singboxConfig.endpoints);
            singboxConfig.endpoints = resultEndpoints;
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }

        return 0;
    }

    /// <summary>
    /// Generates a chained outbound configuration for the given subItem and outbound.
    /// The outbound's tag must be set before calling this method.
    /// Returns the next proxy's outbound configuration, which may be null if no next proxy exists.
    /// </summary>
    /// <param name="subItem">The subscription item containing proxy chain information.</param>
    /// <param name="outbound">The current outbound configuration. Its tag must be set before calling this method.</param>
    /// <param name="prevOutboundTag">The tag of the previous outbound in the chain, if any.</param>
    /// <param name="nextOutbound">The outbound for the next proxy in the chain, if already created. If null, will be created inside.</param>
    /// <returns>
    /// The outbound configuration for the next proxy in the chain, or null if no next proxy exists.
    /// </returns>
    private async Task<BaseServer4Sbox?> GenChainOutbounds(SubItem subItem, BaseServer4Sbox outbound, string? prevOutboundTag, BaseServer4Sbox? nextOutbound = null)
    {
        try
        {
            var txtOutbound = EmbedUtils.GetEmbedText(Global.SingboxSampleOutbound);

            if (!prevOutboundTag.IsNullOrEmpty())
            {
                outbound.detour = prevOutboundTag;
            }

            // Next proxy
            var nextNode = await AppHandler.Instance.GetProfileItemViaRemarks(subItem.NextProfile);
            if (nextNode is not null
                && nextNode.ConfigType != EConfigType.Custom)
            {
                nextOutbound ??= await GenServer(nextNode);
                nextOutbound.tag = outbound.tag;

                outbound.tag = $"mid-{outbound.tag}";
                nextOutbound.detour = outbound.tag;
            }
            return nextOutbound;
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return null;
    }

    private async Task<int> GenRouting(SingboxConfig singboxConfig)
    {
        try
        {
            singboxConfig.route.final = Global.ProxyTag;
            var item = _config.DNSItem;
            singboxConfig.route.default_domain_resolver = new()
            {
                server = "outbound_resolver",
                strategy = item.SingboxStrategy4Direct
            };

            if (_config.TunModeItem.EnableTun)
            {
                singboxConfig.route.auto_detect_interface = true;

                var tunRules = JsonUtils.Deserialize<List<Rule4Sbox>>(EmbedUtils.GetEmbedText(Global.TunSingboxRulesFileName));
                if (tunRules != null)
                {
                    singboxConfig.route.rules.AddRange(tunRules);
                }

                GenRoutingDirectExe(out List<string> lstDnsExe, out List<string> lstDirectExe);
                singboxConfig.route.rules.Add(new()
                {
                    port = new() { 53 },
                    action = "hijack-dns",
                    process_name = lstDnsExe
                });

                singboxConfig.route.rules.Add(new()
                {
                    outbound = Global.DirectTag,
                    process_name = lstDirectExe
                });
            }

            if (_config.Inbound.First().SniffingEnabled)
            {
                singboxConfig.route.rules.Add(new()
                {
                    action = "sniff"
                });
                singboxConfig.route.rules.Add(new()
                {
                    protocol = new() { "dns" },
                    action = "hijack-dns"
                });
            }
            else
            {
                singboxConfig.route.rules.Add(new()
                {
                    port = new() { 53 },
                    network = new() { "udp" },
                    action = "hijack-dns"
                });
            }

            singboxConfig.route.rules.Add(new()
            {
                outbound = Global.DirectTag,
                clash_mode = ERuleMode.Direct.ToString()
            });
            singboxConfig.route.rules.Add(new()
            {
                outbound = Global.ProxyTag,
                clash_mode = ERuleMode.Global.ToString()
            });

            var domainStrategy = _config.RoutingBasicItem.DomainStrategy4Singbox.IsNullOrEmpty() ? null : _config.RoutingBasicItem.DomainStrategy4Singbox;
            var defaultRouting = await ConfigHandler.GetDefaultRouting(_config);
            if (defaultRouting.DomainStrategy4Singbox.IsNotEmpty())
            {
                domainStrategy = defaultRouting.DomainStrategy4Singbox;
            }
            var resolveRule = new Rule4Sbox
            {
                action = "resolve",
                strategy = domainStrategy
            };
            if (_config.RoutingBasicItem.DomainStrategy == "IPOnDemand")
            {
                singboxConfig.route.rules.Add(resolveRule);
            }

            var routing = await ConfigHandler.GetDefaultRouting(_config);
            var ipRules = new List<RulesItem>();
            if (routing != null)
            {
                var rules = JsonUtils.Deserialize<List<RulesItem>>(routing.RuleSet);
                foreach (var item1 in rules ?? [])
                {
                    if (item1.Enabled)
                    {
                        await GenRoutingUserRule(item1, singboxConfig);
                        if (item1.Ip != null && item1.Ip.Count > 0)
                        {
                            ipRules.Add(item1);
                        }
                    }
                }
            }
            if (_config.RoutingBasicItem.DomainStrategy == "IPIfNonMatch")
            {
                singboxConfig.route.rules.Add(resolveRule);
                foreach (var item2 in ipRules)
                {
                    await GenRoutingUserRule(item2, singboxConfig);
                }
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return 0;
    }

    private void GenRoutingDirectExe(out List<string> lstDnsExe, out List<string> lstDirectExe)
    {
        var dnsExeSet = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var directExeSet = new HashSet<string>(StringComparer.OrdinalIgnoreCase);

        var coreInfoResult = CoreInfoHandler.Instance.GetCoreInfo();

        foreach (var coreConfig in coreInfoResult)
        {
            if (coreConfig.CoreType == ECoreType.v2rayN)
            {
                continue;
            }

            foreach (var baseExeName in coreConfig.CoreExes)
            {
                if (coreConfig.CoreType != ECoreType.sing_box)
                {
                    dnsExeSet.Add(Utils.GetExeName(baseExeName));
                }
                directExeSet.Add(Utils.GetExeName(baseExeName));
            }
        }

        lstDnsExe = new List<string>(dnsExeSet);
        lstDirectExe = new List<string>(directExeSet);
    }

    private async Task<int> GenRoutingUserRule(RulesItem item, SingboxConfig singboxConfig)
    {
        try
        {
            if (item == null)
            {
                return 0;
            }
            item.OutboundTag = await GenRoutingUserRuleOutbound(item.OutboundTag, singboxConfig);
            var rules = singboxConfig.route.rules;

            var rule = new Rule4Sbox();
            if (item.OutboundTag == "block")
            {
                rule.action = "reject";
            }
            else
            {
                rule.outbound = item.OutboundTag;
            }

            if (item.Port.IsNotEmpty())
            {
                var portRanges = item.Port.Split(',').Where(it => it.Contains('-')).Select(it => it.Replace("-", ":")).ToList();
                var ports = item.Port.Split(',').Where(it => !it.Contains('-')).Select(it => it.ToInt()).ToList();

                rule.port_range = portRanges.Count > 0 ? portRanges : null;
                rule.port = ports.Count > 0 ? ports : null;
            }
            if (item.Network.IsNotEmpty())
            {
                rule.network = Utils.String2List(item.Network);
            }
            if (item.Protocol?.Count > 0)
            {
                rule.protocol = item.Protocol;
            }
            if (item.InboundTag?.Count >= 0)
            {
                rule.inbound = item.InboundTag;
            }
            var rule1 = JsonUtils.DeepCopy(rule);
            var rule2 = JsonUtils.DeepCopy(rule);
            var rule3 = JsonUtils.DeepCopy(rule);

            var hasDomainIp = false;
            if (item.Domain?.Count > 0)
            {
                var countDomain = 0;
                foreach (var it in item.Domain)
                {
                    if (ParseV2Domain(it, rule1))
                        countDomain++;
                }
                if (countDomain > 0)
                {
                    rules.Add(rule1);
                    hasDomainIp = true;
                }
            }

            if (item.Ip?.Count > 0)
            {
                var countIp = 0;
                foreach (var it in item.Ip)
                {
                    if (ParseV2Address(it, rule2))
                        countIp++;
                }
                if (countIp > 0)
                {
                    rules.Add(rule2);
                    hasDomainIp = true;
                }
            }

            if (_config.TunModeItem.EnableTun && item.Process?.Count > 0)
            {
                rule3.process_name = item.Process;
                rules.Add(rule3);
                hasDomainIp = true;
            }

            if (!hasDomainIp
                && (rule.port != null || rule.port_range != null || rule.protocol != null || rule.inbound != null || rule.network != null))
            {
                rules.Add(rule);
            }
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return await Task.FromResult(0);
    }

    private bool ParseV2Domain(string domain, Rule4Sbox rule)
    {
        if (domain.StartsWith("#") || domain.StartsWith("ext:") || domain.StartsWith("ext-domain:"))
        {
            return false;
        }
        else if (domain.StartsWith("geosite:"))
        {
            rule.geosite ??= [];
            rule.geosite?.Add(domain.Substring(8));
        }
        else if (domain.StartsWith("regexp:"))
        {
            rule.domain_regex ??= [];
            rule.domain_regex?.Add(domain.Replace(Global.RoutingRuleComma, ",").Substring(7));
        }
        else if (domain.StartsWith("domain:"))
        {
            rule.domain ??= [];
            rule.domain_suffix ??= [];
            rule.domain?.Add(domain.Substring(7));
            rule.domain_suffix?.Add("." + domain.Substring(7));
        }
        else if (domain.StartsWith("full:"))
        {
            rule.domain ??= [];
            rule.domain?.Add(domain.Substring(5));
        }
        else if (domain.StartsWith("keyword:"))
        {
            rule.domain_keyword ??= [];
            rule.domain_keyword?.Add(domain.Substring(8));
        }
        else
        {
            rule.domain_keyword ??= [];
            rule.domain_keyword?.Add(domain);
        }
        return true;
    }

    private bool ParseV2Address(string address, Rule4Sbox rule)
    {
        if (address.StartsWith("ext:") || address.StartsWith("ext-ip:"))
        {
            return false;
        }
        else if (address.Equals("geoip:private"))
        {
            rule.ip_is_private = true;
        }
        else if (address.StartsWith("geoip:"))
        {
            rule.geoip ??= new();
            rule.geoip?.Add(address.Substring(6));
        }
        else if (address.Equals("geoip:!private"))
        {
            rule.ip_is_private = false;
        }
        else if (address.StartsWith("geoip:!"))
        {
            rule.geoip ??= new();
            rule.geoip?.Add(address.Substring(6));
            rule.invert = true;
        }
        else
        {
            rule.ip_cidr ??= new();
            rule.ip_cidr?.Add(address);
        }
        return true;
    }

    private async Task<string?> GenRoutingUserRuleOutbound(string outboundTag, SingboxConfig singboxConfig)
    {
        if (Global.OutboundTags.Contains(outboundTag))
        {
            return outboundTag;
        }

        var node = await AppHandler.Instance.GetProfileItemViaRemarks(outboundTag);
        if (node == null
            || node.ConfigType == EConfigType.Custom)
        {
            return Global.ProxyTag;
        }

        var server = await GenServer(node);
        if (server is null)
        {
            return Global.ProxyTag;
        }

        server.tag = Global.ProxyTag + node.IndexId.ToString();
        if (server is Endpoints4Sbox endpoint)
        {
            singboxConfig.endpoints ??= new();
            singboxConfig.endpoints.Add(endpoint);
        }
        else if (server is Outbound4Sbox outbound)
        {
            singboxConfig.outbounds.Add(outbound);
        }

        return server.tag;
    }

    private async Task<int> GenDns(SingboxConfig singboxConfig)
    {
        try
        {
            var dNSItem = _config.DNSItem;
            await GenDnsServers(singboxConfig, dNSItem);
            await GenDnsRules(singboxConfig, dNSItem);

            singboxConfig.dns ??= new Dns4Sbox();
            singboxConfig.dns.independent_cache = true;
            singboxConfig.dns.final = "dns_remote"; // TODO: Select fallback DNS server based on routing rules
        }
        catch (Exception ex)
        {
            Logging.SaveLog(_tag, ex);
        }
        return 0;
    }

    private async Task<int> GenDnsServers(SingboxConfig singboxConfig, DNSItem dNSItem)
    {
        var finalDns = await GenDnsDomains(singboxConfig, dNSItem);

        var directDns = ParseDnsAddress(dNSItem.DirectDNS);
        directDns.tag = "dns_direct";
        directDns.domain_resolver = "final_resolver";

        var remoteDns = ParseDnsAddress(dNSItem.RemoteDNS);
        remoteDns.tag = "dns_remote";
        remoteDns.detour = Global.ProxyTag;
        remoteDns.domain_resolver = "final_resolver";

        var resolverDns = ParseDnsAddress(dNSItem.SingboxOutboundsResolveDNS);
        resolverDns.tag = "outbound_resolver";
        resolverDns.domain_resolver = "final_resolver";

        var hostsDns = new Server4Sbox
        {
            tag = "dns_hosts",
            type = "hosts",
        };
        if (dNSItem.AddCommonHosts == true)
        {
            hostsDns.predefined = Global.PredefinedHosts;
        }
        var userHostsMap = dNSItem.Hosts?
            .Split(new[] { '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries)
            .Where(line => !string.IsNullOrWhiteSpace(line))
            .Where(line => line.Contains(' '))
            .ToDictionary(
                line =>
                {
                    var parts = line.Trim().Split(new[] { ' ', '\t' }, StringSplitOptions.RemoveEmptyEntries);
                    return parts[0];
                },
                line =>
                {
                    var parts = line.Trim().Split(new[] { ' ', '\t' }, StringSplitOptions.RemoveEmptyEntries);
                    var values = parts.Skip(1).ToList();
                    return values;
                }
            );

        if (userHostsMap != null)
        {
            foreach (var kvp in userHostsMap)
            {
                hostsDns.predefined[kvp.Key] = kvp.Value;
            }
        }

        foreach (var host in hostsDns.predefined)
        {
            if (finalDns.server == host.Key)
            {
                finalDns.domain_resolver = "dns_hosts";
            }
            if (remoteDns.server == host.Key)
            {
                remoteDns.domain_resolver = "dns_hosts";
            }
            if (resolverDns.server == host.Key)
            {
                resolverDns.domain_resolver = "dns_hosts";
            }
            if (directDns.server == host.Key)
            {
                directDns.domain_resolver = "dns_hosts";
            }
        }

        singboxConfig.dns ??= new Dns4Sbox();
        singboxConfig.dns.servers ??= new List<Server4Sbox>();
        singboxConfig.dns.servers.Add(remoteDns);
        singboxConfig.dns.servers.Add(directDns);
        singboxConfig.dns.servers.Add(resolverDns);
        singboxConfig.dns.servers.Add(hostsDns);

        // fake ip
        if (dNSItem.FakeIP == true)
        {
            var fakeip = new Server4Sbox
            {
                tag = "dns-fake",
                type = "fakeip",
                inet4_range = "198.18.0.0/15",
                inet6_range = "fc00::/18",
            };
            singboxConfig.dns.servers.Add(fakeip);
        }

        return await Task.FromResult(0);
    }

    private async Task<Server4Sbox> GenDnsDomains(SingboxConfig singboxConfig, DNSItem? dNSItem)
    {
        var finalDns = ParseDnsAddress(dNSItem.SingboxFinalResolveDNS);
        finalDns.tag = "final_resolver";
        singboxConfig.dns ??= new Dns4Sbox();
        singboxConfig.dns.servers ??= new List<Server4Sbox>();
        singboxConfig.dns.servers.Add(finalDns);
        return await Task.FromResult(finalDns);
    }

    private async Task<int> GenDnsRules(SingboxConfig singboxConfig, DNSItem dNSItem)
    {
        singboxConfig.dns ??= new Dns4Sbox();
        singboxConfig.dns.rules ??= new List<Rule4Sbox>();

        singboxConfig.dns.rules.AddRange(new[]
            {
            new Rule4Sbox { ip_accept_any = true, server = "dns_hosts" },
            new Rule4Sbox
            {
                server = "dns_remote",
                strategy = string.IsNullOrEmpty(dNSItem.SingboxStrategy4Proxy) ? null : dNSItem.SingboxStrategy4Proxy,
                clash_mode = ERuleMode.Global.ToString()
            },
            new Rule4Sbox
            {
                server = "dns_direct",
                strategy = string.IsNullOrEmpty(dNSItem.SingboxStrategy4Direct) ? null : dNSItem.SingboxStrategy4Direct,
                clash_mode = ERuleMode.Direct.ToString()
            },
            new Rule4Sbox
            {
                query_type = new List<int> { 64, 65 },
                action = "predefined",
                rcode = "NOTIMP"
            }
        });

        var routing = await ConfigHandler.GetDefaultRouting(_config);
        if (routing == null)
            return 0;

        var rules = JsonUtils.Deserialize<List<RulesItem>>(routing.RuleSet) ?? [];
        var expectedIPCidr = new List<string>();
        var expectedIPsRegions = new List<string>();
        var regionNames = new HashSet<string>();

        if (!string.IsNullOrEmpty(dNSItem?.DirectExpectedIPs))
        {
            var ipItems = dNSItem.DirectExpectedIPs
                .Split(new[] { ',', ';' }, StringSplitOptions.RemoveEmptyEntries)
                .Select(s => s.Trim())
                .Where(s => !string.IsNullOrEmpty(s))
                .ToList();

            foreach (var ip in ipItems)
            {
                if (ip.StartsWith("geoip:", StringComparison.OrdinalIgnoreCase))
                {
                    var region = ip["geoip:".Length..];
                    if (!string.IsNullOrEmpty(region))
                    {
                        expectedIPsRegions.Add(region);
                        regionNames.Add(region);
                        regionNames.Add($"geolocation-{region}");
                        regionNames.Add($"tld-{region}");
                    }
                }
                else
                {
                    expectedIPCidr.Add(ip);
                }
            }
        }

        foreach (var item in rules)
        {
            if (!item.Enabled || item.Domain is null || item.Domain.Count == 0)
            {
                continue;
            }

            var rule = new Rule4Sbox();
            var validDomains = item.Domain.Count(it => ParseV2Domain(it, rule));
            if (validDomains <= 0)
            {
                continue;
            }

            if (item.OutboundTag == Global.DirectTag)
            {
                rule.server = "dns_direct";
                rule.strategy = string.IsNullOrEmpty(dNSItem.SingboxStrategy4Direct) ? null : dNSItem.SingboxStrategy4Direct;

                if (expectedIPsRegions.Count > 0 && rule.geosite?.Count > 0)
                {
                    var geositeSet = new HashSet<string>(rule.geosite);
                    if (regionNames.Intersect(geositeSet).Any())
                    {
                        if (expectedIPsRegions.Count > 0)
                        {
                            rule.geoip = expectedIPsRegions;
                        }
                        if (expectedIPCidr.Count > 0)
                        {
                            rule.ip_cidr = expectedIPCidr;
                        }
                    }
                }
            }
            else if (item.OutboundTag == Global.ProxyTag)
            {
                if (dNSItem.FakeIP == true)
                {
                    var rule4Fake = JsonUtils.DeepCopy(rule);
                    rule4Fake.server = "dns-fake";
                    singboxConfig.dns.rules.Add(rule4Fake);
                }
                rule.server = "dns_remote";
                rule.strategy = string.IsNullOrEmpty(dNSItem.SingboxStrategy4Proxy) ? null : dNSItem.SingboxStrategy4Proxy;
            }
            else if (item.OutboundTag == Global.BlockTag)
            {
                rule.action = "predefined";
                rule.rcode = "NOERROR";
                rule.answer = new List<string> { "A" };
            }

            singboxConfig.dns.rules.Add(rule);
        }

        return 0;
    }

    private static Server4Sbox? ParseDnsAddress(string address)
    {
        var addressFirst = address?.Split(address.Contains(',') ? ',' : ';').FirstOrDefault()?.Trim();
        if (string.IsNullOrEmpty(addressFirst))
        {
            return null;
        }

        var server = new Server4Sbox();

        if (addressFirst is "local" or "localhost")
        {
            server.type = "local";
            return server;
        }

        if (addressFirst.StartsWith("dhcp://", StringComparison.OrdinalIgnoreCase))
        {
            var interface_name = addressFirst.Substring(7);
            server.type = "dhcp";
            server.Interface = interface_name == "auto" ? null : interface_name;
            return server;
        }

        if (!addressFirst.Contains("://"))
        {
            // udp dns
            server.type = "udp";
            server.server = addressFirst;
            return server;
        }

        try
        {
            var protocolEndIndex = addressFirst.IndexOf("://", StringComparison.Ordinal);
            server.type = addressFirst.Substring(0, protocolEndIndex).ToLower();

            var uri = new Uri(addressFirst);
            server.server = uri.Host;

            if (!uri.IsDefaultPort)
            {
                server.server_port = uri.Port;
            }

            if ((server.type == "https" || server.type == "h3") && !string.IsNullOrEmpty(uri.AbsolutePath) && uri.AbsolutePath != "/")
            {
                server.path = uri.AbsolutePath;
            }
        }
        catch (UriFormatException)
        {
            var protocolEndIndex = addressFirst.IndexOf("://", StringComparison.Ordinal);
            if (protocolEndIndex > 0)
            {
                server.type = addressFirst.Substring(0, protocolEndIndex).ToLower();
                var remaining = addressFirst.Substring(protocolEndIndex + 3);

                var portIndex = remaining.IndexOf(':');
                var pathIndex = remaining.IndexOf('/');

                if (portIndex > 0)
                {
                    server.server = remaining.Substring(0, portIndex);
                    var portPart = pathIndex > portIndex
                        ? remaining.Substring(portIndex + 1, pathIndex - portIndex - 1)
                        : remaining.Substring(portIndex + 1);

                    if (int.TryParse(portPart, out var parsedPort))
                    {
                        server.server_port = parsedPort;
                    }
                }
                else if (pathIndex > 0)
                {
                    server.server = remaining.Substring(0, pathIndex);
                }
                else
                {
                    server.server = remaining;
                }

                if (pathIndex > 0 && (server.type == "https" || server.type == "h3"))
                {
                    server.path = remaining.Substring(pathIndex);
                }
            }
        }

        return server;
    }

    private async Task<int> GenExperimental(SingboxConfig singboxConfig)
    {
        //if (_config.guiItem.enableStatistics)
        {
            singboxConfig.experimental ??= new Experimental4Sbox();
            singboxConfig.experimental.clash_api = new Clash_Api4Sbox()
            {
                external_controller = $"{Global.Loopback}:{AppHandler.Instance.StatePort2}",
            };
        }

        if (_config.CoreBasicItem.EnableCacheFile4Sbox)
        {
            singboxConfig.experimental ??= new Experimental4Sbox();
            singboxConfig.experimental.cache_file = new CacheFile4Sbox()
            {
                enabled = true,
                path = Utils.GetBinPath("cache.db"),
                store_fakeip = _config.DNSItem.FakeIP == true
            };
        }

        return await Task.FromResult(0);
    }

    private async Task<int> ConvertGeo2Ruleset(SingboxConfig singboxConfig)
    {
        static void AddRuleSets(List<string> ruleSets, List<string>? rule_set)
        {
            if (rule_set != null)
                ruleSets.AddRange(rule_set);
        }
        var geosite = "geosite";
        var geoip = "geoip";
        var ruleSets = new List<string>();

        //convert route geosite & geoip to ruleset
        foreach (var rule in singboxConfig.route.rules.Where(t => t.geosite?.Count > 0).ToList() ?? [])
        {
            rule.rule_set ??= new List<string>();
            rule.rule_set.AddRange(rule?.geosite?.Select(t => $"{geosite}-{t}").ToList());
            rule.geosite = null;
            AddRuleSets(ruleSets, rule.rule_set);
        }
        foreach (var rule in singboxConfig.route.rules.Where(t => t.geoip?.Count > 0).ToList() ?? [])
        {
            rule.rule_set ??= new List<string>();
            rule.rule_set.AddRange(rule?.geoip?.Select(t => $"{geoip}-{t}").ToList());
            rule.geoip = null;
            AddRuleSets(ruleSets, rule.rule_set);
        }

        //convert dns geosite & geoip to ruleset
        foreach (var rule in singboxConfig.dns?.rules.Where(t => t.geosite?.Count > 0).ToList() ?? [])
        {
            rule.rule_set ??= new List<string>();
            rule.rule_set.AddRange(rule?.geosite?.Select(t => $"{geosite}-{t}").ToList());
            rule.geosite = null;
        }
        foreach (var rule in singboxConfig.dns?.rules.Where(t => t.geoip?.Count > 0).ToList() ?? [])
        {
            rule.rule_set ??= new List<string>();
            rule.rule_set.AddRange(rule?.geoip?.Select(t => $"{geoip}-{t}").ToList());
            rule.geoip = null;
        }
        foreach (var dnsRule in singboxConfig.dns?.rules.Where(t => t.rule_set?.Count > 0).ToList() ?? [])
        {
            AddRuleSets(ruleSets, dnsRule.rule_set);
        }
        //rules in rules
        foreach (var item in singboxConfig.dns?.rules.Where(t => t.rules?.Count > 0).Select(t => t.rules).ToList() ?? [])
        {
            foreach (var item2 in item ?? [])
            {
                AddRuleSets(ruleSets, item2.rule_set);
            }
        }

        //load custom ruleset file
        List<Ruleset4Sbox> customRulesets = [];

        var routing = await ConfigHandler.GetDefaultRouting(_config);
        if (routing.CustomRulesetPath4Singbox.IsNotEmpty())
        {
            var result = EmbedUtils.LoadResource(routing.CustomRulesetPath4Singbox);
            if (result.IsNotEmpty())
            {
                customRulesets = (JsonUtils.Deserialize<List<Ruleset4Sbox>>(result) ?? [])
                    .Where(t => t.tag != null)
                    .Where(t => t.type != null)
                    .Where(t => t.format != null)
                    .ToList();
            }
        }

        //Local srs files address
        var localSrss = Utils.GetBinPath("srss");

        //Add ruleset srs
        singboxConfig.route.rule_set = [];
        foreach (var item in new HashSet<string>(ruleSets))
        {
            if (item.IsNullOrEmpty())
            { continue; }
            var customRuleset = customRulesets.FirstOrDefault(t => t.tag != null && t.tag.Equals(item));
            if (customRuleset is null)
            {
                var pathSrs = Path.Combine(localSrss, $"{item}.srs");
                if (File.Exists(pathSrs))
                {
                    customRuleset = new()
                    {
                        type = "local",
                        format = "binary",
                        tag = item,
                        path = pathSrs
                    };
                }
                else
                {
                    var srsUrl = string.IsNullOrEmpty(_config.ConstItem.SrsSourceUrl)
                        ? Global.SingboxRulesetUrl
                        : _config.ConstItem.SrsSourceUrl;

                    customRuleset = new()
                    {
                        type = "remote",
                        format = "binary",
                        tag = item,
                        url = string.Format(srsUrl, item.StartsWith(geosite) ? geosite : geoip, item),
                        download_detour = Global.ProxyTag
                    };
                }
            }
            singboxConfig.route.rule_set.Add(customRuleset);
        }

        return 0;
    }

    #endregion private gen function
}