using System;
using System.Collections.Generic;
using System.IO;

namespace Rainbow.Services;

/// <summary>Linux 发行版适配工具。处理 Ubuntu/CentOS/Debian 等发行版差异</summary>
public static class DistroAdapter
{
    /// <summary>检测当前发行版</summary>
    public static String DetectDistro()
    {
        try
        {
            // 优先读取 /etc/os-release
            if (File.Exists("/etc/os-release"))
            {
                var lines = File.ReadAllLines("/etc/os-release");
                foreach (var line in lines)
                {
                    if (line.StartsWith("ID="))
                    {
                        var id = line.Substring(3).Trim('"', '\'');
                        if (id == "ubuntu") return "Ubuntu";
                        if (id == "debian") return "Debian";
                        if (id == "centos") return "CentOS";
                        if (id == "rhel") return "RHEL";
                        if (id == "fedora") return "Fedora";
                        return id;
                    }
                }
            }

            // 回退到 lsb_release
            if (File.Exists("/etc/lsb-release"))
            {
                var lines = File.ReadAllLines("/etc/lsb-release");
                foreach (var line in lines)
                    if (line.StartsWith("DISTRIB_ID="))
                        return line.Substring(12).Trim('"', '\'');
            }
        }
        catch { }

        return "Unknown";
    }

    /// <summary>获取发行版对应的包管理器命令</summary>
    public static String GetPackageManager(String distro)
    {
        return distro switch
        {
            "Ubuntu" or "Debian" => "apt",
            "CentOS" or "RHEL" or "Fedora" => "dnf",
            _ => "apt",
        };
    }

    /// <summary>获取发行版对应的服务管理器</summary>
    public static String GetServiceManager() => "systemctl";

    /// <summary>获取发行版适配的包名映射</summary>
    public static Dictionary<String, String> GetPackageNames(String distro)
    {
        var packages = new Dictionary<String, String>
        {
            ["pppoe"] = "pppoe",
            ["dnsmasq"] = "dnsmasq",
            ["iptables"] = "iptables",
            ["wireguard"] = "wireguard-tools",
            ["openvpn"] = "openvpn",
            ["bind9"] = "bind9",
        };

        // CentOS/RHEL 使用不同包名
        if (distro == "CentOS" || distro == "RHEL")
        {
            packages["dnsmasq"] = "dnsmasq";
            packages["bind9"] = "bind";
        }

        return packages;
    }
}