using System.Management;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.Runtime.InteropServices;

namespace DeviceAgent.Services;

public class DeviceInfoService
{
    private readonly ILogger<DeviceInfoService> _logger;

    public DeviceInfoService(ILogger<DeviceInfoService> logger)
    {
        _logger = logger;
    }

    public DeviceInfo GetDeviceInfo()
    {
        var info = new DeviceInfo
        {
            CollectedAt = DateTime.UtcNow
        };

        try
        {
            // 获取系统 UUID
            info.Uuid = GetSystemUuid();
            
            // 获取主机名
            info.Hostname = Environment.MachineName;
            
            // 获取操作系统信息
            info.OsName = RuntimeInformation.OSDescription;
            info.OsVersion = Environment.OSVersion.VersionString;
            info.OsArchitecture = RuntimeInformation.OSArchitecture.ToString();
            
            // 获取网络信息
            var networkInfo = GetNetworkInfo();
            info.IpAddress = networkInfo.IpAddress;
            info.MacAddress = networkInfo.MacAddress;
            info.SubnetMask = networkInfo.SubnetMask;
            info.Gateway = networkInfo.Gateway;
            
            // 获取硬件信息
            info.CpuName = GetCpuName();
            info.TotalMemoryMB = GetTotalMemoryMB();
            info.Manufacturer = GetManufacturer();
            info.Model = GetModel();
            info.SerialNumber = GetSerialNumber();
            
            // 获取磁盘信息
            info.Disks = GetDiskInfo();
            
            // 获取当前登录用户
            info.CurrentUser = Environment.UserName;
            info.UserDomain = Environment.UserDomainName;
            
            // 系统启动时间
            info.BootTime = GetBootTime();
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "获取设备信息失败");
        }

        return info;
    }

    private string GetSystemUuid()
    {
        try
        {
            using var searcher = new ManagementObjectSearcher("SELECT UUID FROM Win32_ComputerSystemProduct");
            foreach (var obj in searcher.Get())
            {
                return obj["UUID"]?.ToString() ?? "";
            }
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "获取系统UUID失败");
        }
        return "";
    }

    private (string IpAddress, string MacAddress, string SubnetMask, string Gateway) GetNetworkInfo()
    {
        string ipAddress = "";
        string macAddress = "";
        string subnetMask = "";
        string gateway = "";

        try
        {
            var interfaces = NetworkInterface.GetAllNetworkInterfaces()
                .Where(n => n.OperationalStatus == OperationalStatus.Up
                    && n.NetworkInterfaceType != NetworkInterfaceType.Loopback
                    && n.NetworkInterfaceType != NetworkInterfaceType.Tunnel)
                .OrderByDescending(n => n.NetworkInterfaceType == NetworkInterfaceType.Ethernet)
                .ThenByDescending(n => n.Speed)
                .ToList();

            foreach (var ni in interfaces)
            {
                var ipProps = ni.GetIPProperties();
                var unicast = ipProps.UnicastAddresses
                    .FirstOrDefault(u => u.Address.AddressFamily == AddressFamily.InterNetwork);

                if (unicast != null)
                {
                    ipAddress = unicast.Address.ToString();
                    macAddress = BitConverter.ToString(ni.GetPhysicalAddress().GetAddressBytes()).Replace("-", ":");
                    subnetMask = unicast.IPv4Mask?.ToString() ?? "";
                    
                    var gw = ipProps.GatewayAddresses
                        .FirstOrDefault(g => g.Address.AddressFamily == AddressFamily.InterNetwork);
                    gateway = gw?.Address.ToString() ?? "";
                    
                    break;
                }
            }
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "获取网络信息失败");
        }

        return (ipAddress, macAddress, subnetMask, gateway);
    }

    private string GetCpuName()
    {
        try
        {
            using var searcher = new ManagementObjectSearcher("SELECT Name FROM Win32_Processor");
            foreach (var obj in searcher.Get())
            {
                return obj["Name"]?.ToString() ?? "";
            }
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "获取CPU信息失败");
        }
        return "";
    }

    private long GetTotalMemoryMB()
    {
        try
        {
            using var searcher = new ManagementObjectSearcher("SELECT TotalPhysicalMemory FROM Win32_ComputerSystem");
            foreach (var obj in searcher.Get())
            {
                var bytes = Convert.ToInt64(obj["TotalPhysicalMemory"]);
                return bytes / 1024 / 1024;
            }
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "获取内存信息失败");
        }
        return 0;
    }

    private string GetManufacturer()
    {
        try
        {
            using var searcher = new ManagementObjectSearcher("SELECT Manufacturer FROM Win32_ComputerSystem");
            foreach (var obj in searcher.Get())
            {
                return obj["Manufacturer"]?.ToString() ?? "";
            }
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "获取制造商信息失败");
        }
        return "";
    }

    private string GetModel()
    {
        try
        {
            using var searcher = new ManagementObjectSearcher("SELECT Model FROM Win32_ComputerSystem");
            foreach (var obj in searcher.Get())
            {
                return obj["Model"]?.ToString() ?? "";
            }
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "获取型号信息失败");
        }
        return "";
    }

    private string GetSerialNumber()
    {
        try
        {
            using var searcher = new ManagementObjectSearcher("SELECT SerialNumber FROM Win32_BIOS");
            foreach (var obj in searcher.Get())
            {
                return obj["SerialNumber"]?.ToString() ?? "";
            }
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "获取序列号失败");
        }
        return "";
    }

    private List<DiskInfo> GetDiskInfo()
    {
        var disks = new List<DiskInfo>();
        try
        {
            foreach (var drive in DriveInfo.GetDrives().Where(d => d.IsReady && d.DriveType == DriveType.Fixed))
            {
                disks.Add(new DiskInfo
                {
                    Name = drive.Name,
                    Label = drive.VolumeLabel,
                    TotalSizeGB = drive.TotalSize / 1024 / 1024 / 1024,
                    FreeSpaceGB = drive.AvailableFreeSpace / 1024 / 1024 / 1024,
                    FileSystem = drive.DriveFormat
                });
            }
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "获取磁盘信息失败");
        }
        return disks;
    }

    private DateTime? GetBootTime()
    {
        try
        {
            var uptime = TimeSpan.FromMilliseconds(Environment.TickCount64);
            return DateTime.Now - uptime;
        }
        catch
        {
            return null;
        }
    }
}

public class DeviceInfo
{
    public string Uuid { get; set; } = "";
    public string Hostname { get; set; } = "";
    public string IpAddress { get; set; } = "";
    public string MacAddress { get; set; } = "";
    public string SubnetMask { get; set; } = "";
    public string Gateway { get; set; } = "";
    
    public string OsName { get; set; } = "";
    public string OsVersion { get; set; } = "";
    public string OsArchitecture { get; set; } = "";
    
    public string CpuName { get; set; } = "";
    public long TotalMemoryMB { get; set; }
    public string Manufacturer { get; set; } = "";
    public string Model { get; set; } = "";
    public string SerialNumber { get; set; } = "";
    
    public List<DiskInfo> Disks { get; set; } = new();
    
    public string CurrentUser { get; set; } = "";
    public string UserDomain { get; set; } = "";
    
    public DateTime? BootTime { get; set; }
    public DateTime CollectedAt { get; set; }
}

public class DiskInfo
{
    public string Name { get; set; } = "";
    public string Label { get; set; } = "";
    public long TotalSizeGB { get; set; }
    public long FreeSpaceGB { get; set; }
    public string FileSystem { get; set; } = "";
}