using Microsoft.Extensions.Logging;
using Microsoft.Win32;
using RmmAgent.Models;
using System.Management;

namespace RmmAgent.Services;

#pragma warning disable CA1416

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

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

    public SystemInfo CollectBasic()
    {
        string osName = "", osVersion = "", osBuild = "", cpuModel = "";
        int ramTotalMb = 0;

        try
        {
            using var os = new ManagementObjectSearcher("SELECT Caption, Version, BuildNumber FROM Win32_OperatingSystem");
            foreach (var o in os.Get())
            {
                osName = o["Caption"]?.ToString() ?? "";
                osVersion = o["Version"]?.ToString() ?? "";
                osBuild = o["BuildNumber"]?.ToString() ?? "";
                break;
            }
        } catch (Exception ex) { _logger.LogWarning(ex, "OS info failed"); }

        try
        {
            using var cpu = new ManagementObjectSearcher("SELECT Name FROM Win32_Processor");
            foreach (var c in cpu.Get()) { cpuModel = c["Name"]?.ToString()?.Trim() ?? ""; break; }
        } catch (Exception ex) { _logger.LogWarning(ex, "CPU info failed"); }

        try
        {
            using var mem = new ManagementObjectSearcher("SELECT TotalPhysicalMemory FROM Win32_ComputerSystem");
            foreach (var m in mem.Get())
            {
                ramTotalMb = (int)(Convert.ToInt64(m["TotalPhysicalMemory"]) / (1024 * 1024));
                break;
            }
        } catch (Exception ex) { _logger.LogWarning(ex, "RAM info failed"); }

        return new SystemInfo(osName, osVersion, osBuild, cpuModel, ramTotalMb);
    }

    public InventoryRequest Collect()
    {
        return new InventoryRequest(
            Hardware: CollectHardware(),
            Software: CollectSoftware(),
            Services: CollectServices(),
            Users: CollectUsers(),
            Security: CollectSecurity());
    }

    private object CollectHardware()
    {
        var data = new Dictionary<string, object?>();

        try {
            using var sys = new ManagementObjectSearcher("SELECT Manufacturer, Model, TotalPhysicalMemory FROM Win32_ComputerSystem");
            foreach (var s in sys.Get()) {
                data["manufacturer"] = s["Manufacturer"]?.ToString();
                data["model"] = s["Model"]?.ToString();
                data["totalRamMb"] = Convert.ToInt64(s["TotalPhysicalMemory"]) / (1024 * 1024);
                break;
            }
        } catch { }

        try {
            using var bios = new ManagementObjectSearcher("SELECT Manufacturer, SerialNumber, SMBIOSBIOSVersion FROM Win32_BIOS");
            foreach (var b in bios.Get()) {
                data["biosVendor"] = b["Manufacturer"]?.ToString();
                data["biosVersion"] = b["SMBIOSBIOSVersion"]?.ToString();
                data["serialNumber"] = b["SerialNumber"]?.ToString();
                break;
            }
        } catch { }

        try {
            var cpus = new List<object>();
            using var cpu = new ManagementObjectSearcher("SELECT Name, NumberOfCores, NumberOfLogicalProcessors, MaxClockSpeed FROM Win32_Processor");
            foreach (var c in cpu.Get())
                cpus.Add(new { name = c["Name"]?.ToString()?.Trim(), cores = c["NumberOfCores"], threads = c["NumberOfLogicalProcessors"], maxClockMhz = c["MaxClockSpeed"] });
            data["cpus"] = cpus;
        } catch { }

        try {
            var disks = new List<object>();
            foreach (var drive in DriveInfo.GetDrives()) {
                if (!drive.IsReady) continue;
                disks.Add(new { name = drive.Name, label = drive.VolumeLabel, fileSystem = drive.DriveFormat, type = drive.DriveType.ToString(), totalGb = Math.Round(drive.TotalSize / 1e9, 2), freeGb = Math.Round(drive.AvailableFreeSpace / 1e9, 2) });
            }
            data["disks"] = disks;
        } catch { }

        try {
            var nics = new List<object>();
            using var net = new ManagementObjectSearcher("SELECT Description, MACAddress, IPAddress FROM Win32_NetworkAdapterConfiguration WHERE IPEnabled = TRUE");
            foreach (var n in net.Get())
                nics.Add(new { description = n["Description"]?.ToString(), mac = n["MACAddress"]?.ToString(), ipAddresses = n["IPAddress"] as string[] });
            data["network"] = nics;
        } catch { }

        try {
            var gpus = new List<object>();
            using var gpu = new ManagementObjectSearcher("SELECT Name, AdapterRAM, DriverVersion FROM Win32_VideoController");
            foreach (var g in gpu.Get())
                gpus.Add(new { name = g["Name"]?.ToString(), vramMb = g["AdapterRAM"] != null ? Convert.ToInt64(g["AdapterRAM"]) / (1024 * 1024) : 0, driver = g["DriverVersion"]?.ToString() });
            data["gpus"] = gpus;
        } catch { }

        return data;
    }

    private object CollectSoftware()
    {
        var apps = new List<object>();
        var keys = new[] {
            @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall",
            @"SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall",
        };
        foreach (var keyPath in keys) {
            try {
                using var key = Registry.LocalMachine.OpenSubKey(keyPath);
                if (key is null) continue;
                foreach (var subName in key.GetSubKeyNames()) {
                    using var sub = key.OpenSubKey(subName);
                    if (sub is null) continue;
                    var name = sub.GetValue("DisplayName") as string;
                    if (string.IsNullOrWhiteSpace(name)) continue;
                    var sc = sub.GetValue("SystemComponent");
                    if (sc is int v && v == 1) continue;
                    apps.Add(new { name, version = sub.GetValue("DisplayVersion") as string, publisher = sub.GetValue("Publisher") as string, installDate = sub.GetValue("InstallDate") as string });
                }
            } catch (Exception ex) { _logger.LogDebug(ex, "Registry walk failed"); }
        }
        return new { count = apps.Count, items = apps };
    }

    private object CollectServices()
    {
        var services = new List<object>();
        try {
            using var s = new ManagementObjectSearcher("SELECT Name, DisplayName, State, StartMode FROM Win32_Service");
            foreach (var svc in s.Get())
                services.Add(new { name = svc["Name"]?.ToString(), displayName = svc["DisplayName"]?.ToString(), state = svc["State"]?.ToString(), startMode = svc["StartMode"]?.ToString() });
        } catch (Exception ex) { _logger.LogWarning(ex, "Services collect failed"); }
        return new { count = services.Count, items = services };
    }

    private object CollectUsers()
    {
        var users = new List<object>();
        try {
            using var u = new ManagementObjectSearcher("SELECT Name, FullName, Disabled FROM Win32_UserAccount WHERE LocalAccount = TRUE");
            foreach (var user in u.Get())
                users.Add(new { name = user["Name"]?.ToString(), fullName = user["FullName"]?.ToString(), disabled = user["Disabled"] });
        } catch (Exception ex) { _logger.LogWarning(ex, "Users collect failed"); }
        return new { items = users };
    }

    private object CollectSecurity()
    {
        var sec = new Dictionary<string, object?>();

        try {
            using var av = new ManagementObjectSearcher(@"\\.\root\SecurityCenter2", "SELECT displayName, productState FROM AntiVirusProduct");
            foreach (var p in av.Get()) {
                sec["antivirus"] = new { product = p["displayName"]?.ToString(), state = p["productState"] };
                break;
            }
        } catch { sec["antivirus"] = null; }

        try {
            using var bl = new ManagementObjectSearcher(@"\\.\root\CIMv2\Security\MicrosoftVolumeEncryption", "SELECT * FROM Win32_EncryptableVolume");
            int encrypted = 0, total = 0;
            foreach (var v in bl.Get()) {
                total++;
                if (v["ProtectionStatus"] is int s && s == 1) encrypted++;
            }
            sec["bitlocker"] = new { enabled = encrypted > 0, encryptedVolumes = encrypted, totalVolumes = total };
        } catch { sec["bitlocker"] = new { enabled = false }; }

        try {
            using var fw = new ManagementObjectSearcher(@"\\.\root\StandardCimv2", "SELECT * FROM MSFT_NetFirewallProfile");
            bool anyEnabled = false;
            foreach (var p in fw.Get()) {
                if (p["Enabled"] is ushort u && u == 1) { anyEnabled = true; break; }
                if (p["Enabled"] is bool b && b) { anyEnabled = true; break; }
            }
            sec["firewall"] = new { enabled = anyEnabled };
        } catch { sec["firewall"] = new { enabled = false }; }

        return sec;
    }
}