using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.Management;
using System.Text;
using System.Threading.Tasks;

namespace Hopetry.Provider
{
    public class SystemInfo
    {
        public string MachineId { get; set; }
        public HardwareInfo Hardware { get; set; }
        public OSInfo OS { get; set; }
        public NetworkInfo Network { get; set; }
        public DateTime Timestamp { get; set; }
    }

    public class HardwareInfo
    {
        public string CPU { get; set; }
        public string CPUID { get; set; }
        public string Memory { get; set; }
        public List<DiskInfo> Disks { get; set; }
    }

    public class DiskInfo
    {
        public string Model { get; set; }
        public string Size { get; set; }
    }

    public class OSInfo
    {
        public string Version { get; set; }
        public DateTime InstallDate { get; set; }
    }

    public class NetworkInfo
    {
        public string IPv4 { get; set; }
        public string MAC { get; set; }
    }

    public static class SystemInfoCollector
    {
        public static SystemInfo Collect()
        {
            return new SystemInfo
            {
                MachineId = GetMACAddress(),
                Timestamp = DateTime.UtcNow,
                Hardware = new HardwareInfo
                {
                    CPU = GetCPUInfo(),
                    CPUID = GetCPUID(),
                    Memory = $"{GetTotalMemory()}GB",
                    Disks = GetDiskInfo()
                },
                OS = new OSInfo
                {
                    Version = GetOSVersion(),
                    InstallDate = GetOSInstallDate()
                },
                Network = new NetworkInfo
                {
                    IPv4 = GetIPv4Address(),
                    MAC = GetMACAddress()
                }
            };
        }

        private static string GetCPUInfo()
        {
            using var searcher = new ManagementObjectSearcher("SELECT Name FROM Win32_Processor");
            return searcher.Get().Cast<ManagementObject>().First()["Name"].ToString();
        }

        private static string GetCPUID()
        {
            using var searcher = new ManagementObjectSearcher("SELECT ProcessorId FROM Win32_Processor");
            return searcher.Get().Cast<ManagementObject>().First()["ProcessorId"].ToString();
        }

        private static double GetTotalMemory()
        {
            using var searcher = new ManagementObjectSearcher("SELECT Capacity FROM Win32_PhysicalMemory");
            var total = searcher.Get()
                .Cast<ManagementObject>()
                .Sum(m => Convert.ToDouble(m["Capacity"])) / (1024 * 1024 * 1024);
            return Math.Round(total, 1);
        }

        private static List<DiskInfo> GetDiskInfo()
        {
            using var searcher = new ManagementObjectSearcher("SELECT Model,Size FROM Win32_DiskDrive");
            return searcher.Get().Cast<ManagementObject>().Select(m => new DiskInfo
            {
                Model = m["Model"].ToString().Trim(),
                Size = $"{Convert.ToDouble(m["Size"]) / (1024 * 1024 * 1024):N1}GB"
            }).ToList();
        }

        private static string GetOSVersion()
        {
            using var searcher = new ManagementObjectSearcher("SELECT Caption,Version FROM Win32_OperatingSystem");
            var os = searcher.Get().Cast<ManagementObject>().First();
            return $"{os["Caption"]} {os["Version"]}";
        }

        private static DateTime GetOSInstallDate()
        {
            using var searcher = new ManagementObjectSearcher("SELECT InstallDate FROM Win32_OperatingSystem");
            var installDate = searcher.Get().Cast<ManagementObject>().First()["InstallDate"].ToString();
            return ManagementDateTimeConverter.ToDateTime(installDate);
        }

        private static string GetIPv4Address()
        {
            return NetworkInterface.GetAllNetworkInterfaces()
                .Where(n => n.OperationalStatus == OperationalStatus.Up)
                .SelectMany(n => n.GetIPProperties().UnicastAddresses)
                .FirstOrDefault(a => a.Address.AddressFamily == AddressFamily.InterNetwork)?.Address.ToString();
        }

        private static string GetMACAddress()
        {
            return NetworkInterface.GetAllNetworkInterfaces()
                .Where(n => n.OperationalStatus == OperationalStatus.Up)
                .Select(n => n.GetPhysicalAddress().ToString())
                .FirstOrDefault() ?? string.Empty;
        }
    }
}