using System.Runtime.Versioning;
using System.Security.Principal;
using Duplicati.Library.Snapshots;
using Duplicati.WebserverCore.Abstractions;
using Duplicati.WebserverCore.Exceptions;
using Microsoft.AspNetCore.Mvc;

namespace Duplicati.WebserverCore.Endpoints.V1;

public class HyperV : IEndpointV1
{
    public static void Map(RouteGroupBuilder group)
    {
        group.MapGet("/hyperv", () => Execute(null)).RequireAuthorization();
        group.MapGet("/hyperv/{key}", ([FromRoute] string key) => Execute(key)).RequireAuthorization();
    }

    private static IEnumerable<Dto.TreeNodeDto> Execute(string? key)
    {
        if (!OperatingSystem.IsWindows())
            return [];

        return ExecuteOnWindows(key);
    }

    // Make sure the JIT does not attempt to inline this call and thus load
    // referenced types from System.Management here
    [SupportedOSPlatform("windows")]
    [System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.NoInlining)]
    private static IEnumerable<Dto.TreeNodeDto> ExecuteOnWindows(string? key)
    {
        var hypervUtility = new HyperVUtility();

        if (!hypervUtility.IsHyperVInstalled || !new WindowsPrincipal(WindowsIdentity.GetCurrent()).IsInRole(WindowsBuiltInRole.Administrator))
            return [];

        try
        {
            if (string.IsNullOrEmpty(key))
            {
                hypervUtility.QueryHyperVGuestsInfo();
                return hypervUtility.Guests.Select(x => new Dto.TreeNodeDto()
                {
                    id = x.ID.ToString(),
                    text = x.Name,
                    cls = "hyperv",
                    iconCls = "x-tree-icon-hyperv",
                    check = false,
                    temporary = false,
                    leaf = false,
                    systemFile = false,
                    hidden = false,
                    symlink = false,
                    fileSize = -1,
                    resolvedpath = null
                }).ToList();
            }
            else
            {
                hypervUtility.QueryHyperVGuestsInfo(true);
                var foundVMs = hypervUtility.Guests.FindAll(x => x.ID.Equals(new Guid(key)));

                if (foundVMs.Count != 1)
                    throw new NotFoundException(string.Format($"Cannot find VM with ID {key}"));
                return foundVMs[0].DataPaths.Select(x => new Dto.TreeNodeDto()
                {
                    text = x,
                    id = x,
                    cls = "folder",
                    iconCls = "x-tree-icon-hypervmachine",
                    check = false,
                    leaf = true,
                    hidden = false,
                    systemFile = false,
                    temporary = false,
                    symlink = false,
                    fileSize = -1,
                    resolvedpath = null
                }).ToList();
            }
        }
        catch (Exception ex)
        {
            throw new Exception($"Failed to enumerate Hyper-V virtual machines: {ex.Message}", ex);
        }
    }
}