using System.Collections;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using System.Linq;
using Vanara.Collections;
using Vanara.PInvoke;
using static Vanara.PInvoke.SetupAPI;

namespace Vanara.Diagnostics;

/// <summary>A dictionary of properties.</summary>
/// <typeparam name="TKey">The type of the key.</typeparam>
/// <typeparam name="TValue">The type of the value.</typeparam>
/// <seealso cref="System.Collections.Generic.IDictionary{TKey, TValue}"/>
public interface IPropertyProvider<TKey, TValue> : IDictionary<TKey, TValue> where TKey : notnull
{
}

/// <summary>Extension methods for SetupAPI functions and structs.</summary>
public static class DeviceExtensions
{
	/// <summary>
	/// Trys to get friendly name for the property key. If not available via <c>PSGetNameFromPropertyKey</c>, then the name of the
	/// defined field is returned (i.e. "DEVPKEY_Device_Class"). If not available, then the Guid and ID are returned.
	/// </summary>
	/// <param name="propKey">The property key.</param>
	/// <returns>The best string representation available.</returns>
	public static string LookupName(this DEVPROPKEY propKey)
	{
		if (PropSys.PSGetNameFromPropertyKey(new Ole32.PROPERTYKEY(propKey.fmtid, propKey.pid), out var str).Succeeded)
			return str;
		return LookupField(propKey)?.Name ?? $"{propKey.fmtid:B}[{propKey.pid}]";
	}

	internal static IEnumerable<Type> GetCorrespondingTypes(this DEVPROPKEY propKey)
	{
		var fi = LookupField(propKey);
		if (fi is null) return Enumerable.Empty<Type>();
		return fi.GetCustomAttributes<CorrespondingTypeAttribute>().Select(a => a.TypeRef).WhereNotNull();
	}

	internal static System.Reflection.FieldInfo? LookupField(this DEVPROPKEY propKey) =>
		typeof(SetupAPI).GetFields(System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.Public).
		Where(fi => fi.FieldType == typeof(DEVPROPKEY) && fi.Name.StartsWith("DEVPKEY") && propKey.Equals((DEVPROPKEY)fi.GetValue(null)!)).FirstOrDefault();
}

/// <summary>A class that represents a device on a machine.</summary>
public class Device : IDisposable
{
	private readonly SafeHDEVINFO hdi;
	private readonly Lazy<SP_DEVINSTALL_PARAMS> instParam;
	private readonly Lazy<string> name, desc, instId;
	private SP_DEVINFO_DATA data;
	private DeviceProperties? props;
	private DeviceRegProperties? rprops;

	internal Device(SafeHDEVINFO hdi, SP_DEVINFO_DATA data)
	{
		this.hdi = hdi;
		this.data = data;
		name = new Lazy<string>(() => Properties[DEVPKEY_NAME]?.ToString() ?? "");
		desc = new Lazy<string>(() => RegistryProperties[SPDRP.SPDRP_DEVICEDESC]?.ToString() ?? "");
		instId = new Lazy<string>(() => Properties[DEVPKEY_Device_InstanceId]?.ToString() ?? "");
		instParam = new Lazy<SP_DEVINSTALL_PARAMS>(GetInstallParams);
	}

	/// <summary>The GUID of the device's setup class.</summary>
	public Guid ClassGuid => data.ClassGuid;

	/// <summary>Gets the data the identifies the device.</summary>
	/// <value>A SP_DEVINFO_DATA structure with identifying device information.</value>
	public SP_DEVINFO_DATA Data => data;

	/// <summary>The description of the device instance.</summary>
	/// <value>The description.</value>
	public string Description => desc.Value;

	/// <summary>Gets the driver path.</summary>
	public string DriverPath => instParam.Value.DriverPath;

	/// <summary>Gets the handle to the device.</summary>
	/// <value>A HDEVINFO handle.</value>
	public HDEVINFO Handle => hdi;

	/// <summary>
	/// Gets the flags that control installation and user interface operations. Some flags can be set before sending the device
	/// installation request while other flags are set automatically during the processing of some requests.
	/// </summary>
	public DI_FLAGS InstallFlags => instParam.Value.Flags;

	/// <summary>
	/// Gets additional flags that provide control over installation and user interface operations. Some flags can be set before calling
	/// the device installer functions while other flags are set automatically during the processing of some functions.
	/// </summary>
	public DI_FLAGSEX InstallFlagsEx => instParam.Value.FlagsEx;

	/// <summary>The instance identifier of the device instance.</summary>
	/// <value>The instance identifier.</value>
	public string InstanceId => instId.Value;

	/// <summary>
	/// A string that contains the name of the remote computer. If the device information set is for the local computer, this member is
	/// <see langword="null"/>.
	/// </summary>
	public string? MachineName => hdi.MachineName;

	/// <summary>The name of the device instance.</summary>
	/// <value>The name.</value>
	public string Name => name.Value;

	/// <summary>Gets a dictionary of properties.</summary>
	/// <value>The properties.</value>
	public IPropertyProvider<DEVPROPKEY, object?> Properties =>
		props ??= (MachineName is null ? new DeviceProperties(this) : throw new InvalidOperationException("Properties cannot be retrieved for remote devices."));

	/// <summary>Gets a dictionary of registry properties.</summary>
	/// <value>The registry properties.</value>
	public IPropertyProvider<SPDRP, object?> RegistryProperties =>
		rprops ??= (MachineName is null ? new DeviceRegProperties(this) : throw new InvalidOperationException("Properties cannot be retrieved for remote devices."));

	/// <inheritdoc/>
	public void Dispose() { }

	/// <summary>Retrieves a specified custom device property from the registry.</summary>
	/// <param name="propName">A registry value name representing a custom property.</param>
	/// <param name="combine">
	/// If <see langword="true"/>, the function retrieves both device instance-specific property values and hardware ID-specific
	/// property values, concatenated as a REG_MULTI_SZ-typed string.
	/// </param>
	/// <returns>The requested property information or <see langword="null"/> if the property does not exist.</returns>
	public object? GetCustomProperty(string propName, bool combine = false)
	{
		if (!SetupDiGetCustomDeviceProperty(hdi, data, propName, combine ? DICUSTOMDEVPROP.DICUSTOMDEVPROP_MERGE_MULTISZ : 0, out _, default, 0, out var bufSz) &&
			Win32Error.GetLastError() == Win32Error.ERROR_INSUFFICIENT_BUFFER)
		{
			using var mem = new SafeCoTaskMemHandle(bufSz);
			Win32Error.ThrowLastErrorIfFalse(SetupDiGetCustomDeviceProperty(hdi, data, propName, combine ? DICUSTOMDEVPROP.DICUSTOMDEVPROP_MERGE_MULTISZ : 0, out var regType, mem, mem.Size, out bufSz));
			return DeviceClass.DeviceClassRegProperties.GetRegValue(mem, regType);
		}
		return null;
	}

	/// <summary>Retrieves an icon for this device.</summary>
	/// <param name="iconSize">
	/// The size, in pixels, of the icon to be retrieved. Use the system metric index SM_CXICON to specify a default-sized icon or use
	/// the system metric index SM_CXSMICON to specify a small icon.
	/// </param>
	/// <returns>A safe handle to the icon that this function retrieves.</returns>
	/// <remarks>
	/// <para><c>GetIcon</c> attempts to retrieve an icon for the device as follows:</para>
	/// <list type="bullet">
	/// <item>
	/// <term>
	/// If the DEVPKEY_DrvPkg_Icon device property of the device includes a list of resource-identifier strings, the function attempts
	/// to retrieve the icon that is specified by the first resource-identifier string in the list.
	/// </term>
	/// </item>
	/// <item>
	/// <term>
	/// If the function cannot retrieve a device-specific icon, it will then attempt to retrieve the class icon for the device. For
	/// information about class icons, see SetupDiLoadClassIcon.
	/// </term>
	/// </item>
	/// <item>
	/// <term>
	/// If the function cannot retrieve the class icon for the device, it will then attempt to retrieve the icon for the Unknown device
	/// setup class, where the icon for the Unknown device setup class includes the image of a question mark (?).
	/// </term>
	/// </item>
	/// </list>
	/// </remarks>
	public User32.SafeHICON GetIcon(System.Drawing.Size iconSize)
	{
		Win32Error.ThrowLastErrorIfFalse(SetupDiLoadDeviceIcon(hdi, data, (uint)iconSize.Width, (uint)iconSize.Height, 0, out var hIcon));
		return new User32.SafeHICON((IntPtr)hIcon);
	}

	private SP_DEVINSTALL_PARAMS GetInstallParams()
	{
		var p = StructHelper.InitWithSize<SP_DEVINSTALL_PARAMS>();
		Win32Error.ThrowLastErrorIfFalse(SetupDiGetDeviceInstallParams(hdi, data, ref p));
		return p;
	}

	/// <summary>Accesses properties with a device.</summary>
	public class DeviceProperties : VirtualDictionary<DEVPROPKEY, object?>, IPropertyProvider<DEVPROPKEY, object?>
	{
		private readonly Device parent;

		internal DeviceProperties(Device dev) : base(false) => parent = dev;

		private DeviceProperties() : base(false) => throw new InvalidOperationException();

		/// <inheritdoc/>
		public override int Count
		{
			get
			{
				SetupDiGetDevicePropertyKeys(parent.hdi, parent.data, null, 0, out var cnt);
				Win32Error.ThrowLastErrorUnless(Win32Error.ERROR_INSUFFICIENT_BUFFER);
				return (int)cnt;
			}
		}

		/// <inheritdoc/>
		public override ICollection<DEVPROPKEY> Keys
		{
			get
			{
				SetupDiGetDevicePropertyKeys(parent.hdi, parent.data, null, 0, out var cnt);
				Win32Error.ThrowLastErrorUnless(Win32Error.ERROR_INSUFFICIENT_BUFFER);
				var propKeys = new DEVPROPKEY[(int)cnt];
				Win32Error.ThrowLastErrorIfFalse(SetupDiGetDevicePropertyKeys(parent.hdi, parent.data, propKeys, cnt, out _));
				return propKeys;
			}
		}

		/// <inheritdoc/>
		public override bool Remove(DEVPROPKEY key) =>
			SetupDiSetDeviceProperty(parent.hdi, parent.data, key, 0, default, 0);

		/// <inheritdoc/>
		public override bool TryGetValue(DEVPROPKEY key, [NotNullWhen(true)] out object? value) => (uint)GetValue(key, out value) is Win32Error.ERROR_SUCCESS or Win32Error.ERROR_NOT_FOUND;

		/// <inheritdoc/>
		protected override void SetValue(DEVPROPKEY key, object? value)
		{
			value = DeviceClass.DeviceClassProperties.CommonPropConv(value);
			var type = GetPropType(key, value?.GetType());
			var mem = DeviceClass.DeviceClassProperties.PrepValue(value, type);
			try
			{
				if (mem is null)
					throw new ArgumentException("Unable to convert object to property type.", nameof(value));
				Win32Error.ThrowLastErrorIfFalse(SetupDiSetDeviceProperty(parent.hdi, parent.data, key, type, mem.DangerousGetHandle(), mem.Size));
			}
			finally
			{
				mem?.Dispose();
			}
		}

		private DEVPROPTYPE GetPropType(DEVPROPKEY propKey, Type? valType)
		{
			if (SetupDiGetDeviceProperty(parent.hdi, parent.data, propKey, out var type, default, default, out _))
				return type;
			var fi = typeof(DEVPROPTYPE).GetFields().Where(fi => fi.IsLiteral && fi.GetCustomAttributes<CorrespondingTypeAttribute>(false, a => a.TypeRef == valType).Any()).FirstOrDefault();
			return fi is not null ? (DEVPROPTYPE)fi.GetValue(null)! : throw new ArgumentException("Unable to determine DEVPROPTYPE.");
		}

		private Win32Error GetValue(in DEVPROPKEY propKey, out object? value)
		{
			value = null;
			if (!SetupDiGetDeviceProperty(parent.hdi, parent.data, propKey, out _, default, 0, out var bufSz))
			{
				var err = Win32Error.GetLastError();
				if (err != Win32Error.ERROR_INSUFFICIENT_BUFFER)
					return err;
				using var mem = new SafeCoTaskMemHandle(bufSz);
				if (!SetupDiGetDeviceProperty(parent.hdi, parent.data, propKey, out var propType, mem, mem.Size, out bufSz))
					return Win32Error.GetLastError();
				value = SetupDiPropertyToManagedObject(mem, propType, propKey.GetCorrespondingTypes().FirstOrDefault());
			}
			return Win32Error.ERROR_SUCCESS;
		}
	}

	/// <summary>Accesses registry properties with a device class.</summary>
	public class DeviceRegProperties : VirtualDictionary<SPDRP, object?>, IPropertyProvider<SPDRP, object?>
	{
		private readonly Device parent;

		internal DeviceRegProperties(Device dev) : base(false) => parent = dev;

		private DeviceRegProperties() : base(false) => throw new InvalidOperationException();

		/// <inheritdoc/>
		public override int Count => Enum.GetValues(typeof(SPDRP)).Length;

		/// <inheritdoc/>
		public override ICollection<SPDRP> Keys => (ICollection<SPDRP>)Enum.GetValues(typeof(SPDRP));

		/// <inheritdoc/>
		public override bool Remove(SPDRP key) => SetupDiSetDeviceRegistryProperty(parent.hdi, ref parent.data, key, default, 0);

		/// <inheritdoc/>
		public override bool TryGetValue(SPDRP key, [NotNullWhen(true)] out object? value) => (uint)GetValue(key, out value) is Win32Error.ERROR_SUCCESS or Win32Error.ERROR_NOT_FOUND;

		/// <inheritdoc/>
		protected override void SetValue(SPDRP key, object? value)
		{
			if (value is null)
				throw new ArgumentNullException(nameof(value));
			value = DeviceClass.DeviceClassRegProperties.CommonPropConv(value);
			if (!CorrespondingTypeAttribute.CanSet(key, value.GetType()))
				throw new ArgumentException("Value type not valid for key.");
			SafeAllocatedMemoryHandle mem = value switch
			{
				var v when v.GetType().IsValueType && !v.GetType().IsEnum => SafeCoTaskMemHandle.CreateFromStructure(value),
				var v when v.GetType().IsValueType && v.GetType().IsEnum => SafeCoTaskMemHandle.CreateFromStructure((uint)value),
				IEnumerable<string> ies => SafeCoTaskMemHandle.CreateFromStringList(ies),
				byte[] ba => new SafeCoTaskMemHandle(ba),
				string s => new SafeCoTaskMemString(s, CharSet.Auto),
				_ => throw new ArgumentException("Unable to convert object to property type.", nameof(value))
			};
			try
			{
				Win32Error.ThrowLastErrorIfFalse(SetupDiSetDeviceRegistryProperty(parent.hdi, ref parent.data, key, mem.DangerousGetHandle(), mem.Size));
			}
			finally
			{
				mem?.Dispose();
			}
		}

		private Win32Error GetValue(SPDRP propKey, out object? value)
		{
			value = null;
			if (!SetupDiGetDeviceRegistryProperty(parent.hdi, parent.data, propKey, out _, default, 0, out var bufSz))
			{
				if (bufSz == 0)
					return Win32Error.ERROR_NOT_FOUND;
				using var mem = new SafeCoTaskMemHandle(bufSz);
				if (!SetupDiGetDeviceRegistryProperty(parent.hdi, parent.data, propKey, out var propType, mem, mem.Size, out bufSz))
					return Win32Error.GetLastError();
				value = DeviceClass.DeviceClassRegProperties.GetRegValue(propKey, mem, propType);
			}
			return Win32Error.ERROR_SUCCESS;
		}
	}
}

/// <summary>A class that provides detail about a device setup class available on a machine.</summary>
/// <remarks>
/// Device setup classes provide a mechanism for grouping devices that are installed and configured in the same way. A setup class
/// identifies the class installer and class co-installers that are involved in installing the devices that belong to the class. For
/// example, all CD-ROM drives belong to the CDROM setup class and will use the same co-installer when installed.
/// </remarks>
public class DeviceClass : IDisposable
{
	private static readonly Dictionary<string, SP_CLASSIMAGELIST_DATA> imgListData = new();
#pragma warning disable IDE0052 // Remove unread private members
	private static readonly FinalizeImgLists imgListFinalizer = new();
#pragma warning restore IDE0052 // Remove unread private members
	private readonly Lazy<int?> bmpIdx, imgIdx;
	private readonly Lazy<string> name, desc;
	private DeviceClassProperties? props;
	private DeviceClassRegProperties? rprops;

	/// <summary>Initializes a new instance of the <see cref="DeviceClass"/> class with its GUID and optional machine name.</summary>
	/// <param name="guid">The GUID for the device setup class.</param>
	/// <param name="machineName">
	/// The name of the machine on which devices are managed. <see langword="null"/> indicates the local machine.
	/// </param>
	public DeviceClass(Guid guid, string? machineName = null)
	{
		Guid = guid;
		MachineName = machineName;
		name = new Lazy<string>(() => GetClassString(SetupDiClassNameFromGuidEx, 32));
		desc = new Lazy<string>(() => GetClassString(SetupDiGetClassDescriptionEx, 256));
		bmpIdx = new Lazy<int?>(() => SetupDiGetClassBitmapIndex(Guid, out var idx) ? idx : null);
		imgIdx = new Lazy<int?>(() => SetupDiGetClassImageIndex(GetImageList(), Guid, out var idx) ? idx : null);
	}

	/// <summary>Initializes a new instance of the <see cref="DeviceClass"/> class from its class name and optional machine name.</summary>
	/// <param name="name">The name of the class.</param>
	/// <param name="machineName">
	/// The name of the machine on which devices are managed. <see langword="null"/> indicates the local machine.
	/// </param>
	public DeviceClass(string name, string? machineName = null) : this(FromName(name, machineName), machineName)
	{
	}

	private delegate bool GetClassStringDelegate(in Guid ClassGuid, StringBuilder ClassName, uint ClassNameSize, out uint RequiredSize,
		string? MachineName, IntPtr Reserved = default);

	/// <summary>Gets the index of the mini-icon supplied for this class.</summary>
	/// <value>The index of the mini-icon supplied for this class.</value>
	public int? BitmapIndex => bmpIdx.Value;

	/// <summary>Gets the class description associated with the specified setup class GUID.</summary>
	/// <value>The class description associated with the specified setup class GUID.</value>
	/// <remarks>
	/// If there is a friendly name in the registry key for the class, this routine returns the friendly name. Otherwise, this routine
	/// returns the class name.
	/// </remarks>
	public string Description => desc.Value;

	/// <summary>Gets the GUID for this setup class.</summary>
	/// <value>The GUID for this setup class.</value>
	public Guid Guid { get; }

	/// <summary>Gets the index within the class image list.</summary>
	/// <value>The index within the class image list.</value>
	public int? ImageIndex => imgIdx.Value;

	/// <summary>Gets the image list of bitmaps for every class installed on this system.</summary>
	/// <value>The image list handle of bitmaps for every class installed on this system.</value>
	public HIMAGELIST ImageListHandle => GetImageList().ImageList;

	/// <summary>Gets the name of the machine on which devices are managed. <see langword="null"/> indicates the local machine.</summary>
	/// <value>The machine name for this manager.</value>
	public string? MachineName { get; }

	/// <summary>Gets the class name associated with a class GUID.</summary>
	/// <value>The class name associated with a class GUID.</value>
	public string Name => name.Value;

	/// <summary>Gets a value that controls whether devices in this setup class are displayed by the Device Manager.</summary>
	public bool? NoDisplay => Properties.TryGetValue(DEVPKEY_DeviceClass_NoDisplayClass, out var val) ? (bool?)val : null;

	/// <summary>Gets a value that controls whether devices in this device setup class are displayed in the <c>Add Hardware Wizard</c>.</summary>
	public bool? NoInstall => (bool?)Properties[DEVPKEY_DeviceClass_NoInstallClass];

	/// <summary>Gets a dictionary of properties.</summary>
	/// <value>The properties.</value>
	public IPropertyProvider<DEVPROPKEY, object?> Properties => props ??= new DeviceClassProperties(Guid, MachineName);

	/// <summary>Gets a dictionary of registry properties.</summary>
	/// <value>The registry properties.</value>
	public IPropertyProvider<SPCRP, object?> RegistryProperties => rprops ??= new DeviceClassRegProperties(Guid, MachineName);

	/// <summary>Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.</summary>
	public void Dispose()
	{
	}

	/// <summary>Gets the devices associated with this device class.</summary>
	/// <returns>A sequence of <see cref="Device"/> instances with this device class.</returns>
	public IEnumerable<Device> GetDevices() => new DeviceCollection(Guid, null, MachineName);

	private static Guid FromName(string name, string? machine)
	{
		SetupDiClassGuidsFromNameEx(name, null, 0, out var len, machine);
		if (len == 0) Win32Error.ThrowLastError();
		var guids = new Guid[(int)len];
		Win32Error.ThrowLastErrorIfFalse(SetupDiClassGuidsFromNameEx(name, guids, len, out _, machine));
		return guids[0];
	}

	private string GetClassString(GetClassStringDelegate f, uint initSz)
	{
		var sz = initSz;
		var sb = new StringBuilder((int)sz);
		if (!f(Guid, sb, sz, out sz, MachineName))
		{
			Win32Error.ThrowLastErrorUnless(Win32Error.ERROR_INSUFFICIENT_BUFFER);
			sb.Capacity = (int)sz;
			Win32Error.ThrowLastErrorIfFalse(f(Guid, sb, sz, out _, MachineName));
		}
		return sb.ToString();
	}

	private SP_CLASSIMAGELIST_DATA GetImageList()
	{
		if (!imgListData.TryGetValue(MachineName ?? "", out var data))
		{
			data = StructHelper.InitWithSize<SP_CLASSIMAGELIST_DATA>();
			Win32Error.ThrowLastErrorIfFalse(SetupDiGetClassImageListEx(ref data, MachineName));
			imgListData.Add(MachineName ?? "", data);
		}
		return data;
	}

	/// <summary>Accesses properties with a device class.</summary>
	public class DeviceClassProperties : VirtualDictionary<DEVPROPKEY, object?>, IPropertyProvider<DEVPROPKEY, object?>
	{
		private readonly Guid Guid;

		private readonly string? MachineName;

		internal DeviceClassProperties(Guid guid, string? machineName) : base(false)
		{
			Guid = guid;
			MachineName = machineName;
		}

		private DeviceClassProperties() : base(false) => throw new InvalidOperationException();

		/// <inheritdoc/>
		public override int Count
		{
			get
			{
				SetupDiGetClassPropertyKeysEx(Guid, null, 0, out var cnt, DICLASSPROP.DICLASSPROP_INSTALLER, MachineName);
				Win32Error.ThrowLastErrorUnless(Win32Error.ERROR_INSUFFICIENT_BUFFER);
				return (int)cnt;
			}
		}

		/// <inheritdoc/>
		public override ICollection<DEVPROPKEY> Keys
		{
			get
			{
				SetupDiGetClassPropertyKeysEx(Guid, null, 0, out var cnt, DICLASSPROP.DICLASSPROP_INSTALLER, MachineName);
				Win32Error.ThrowLastErrorUnless(Win32Error.ERROR_INSUFFICIENT_BUFFER);
				var propKeys = new DEVPROPKEY[(int)cnt];
				Win32Error.ThrowLastErrorIfFalse(SetupDiGetClassPropertyKeysEx(Guid, propKeys, cnt, out _, DICLASSPROP.DICLASSPROP_INSTALLER, MachineName));
				return propKeys;
			}
		}

		/// <inheritdoc/>
		public override bool Remove(DEVPROPKEY key) =>
			SetupDiSetClassPropertyEx(Guid, key, 0, default, 0, DICLASSPROP.DICLASSPROP_INSTALLER, MachineName);

		/// <inheritdoc/>
		public override bool TryGetValue(DEVPROPKEY key, [NotNullWhen(true)] out object? value) => (uint)GetValue(key, out value) is Win32Error.ERROR_SUCCESS or Win32Error.ERROR_NOT_FOUND;

		internal static object? CommonPropConv(object? value) => value switch
		{
			bool b => (BOOLEAN)b,
			DateTime dt => dt.ToFileTimeStruct(),
			decimal dec => new CY(dec),
			ISafeMemoryHandle h => h.GetBytes(0, h.Size),
			_ => value,
		};

		internal static ISafeMemoryHandle PrepValue(object? value, DEVPROPTYPE type)
		{
			// Changes types that need conversion or quick outs
			if (value is null)
				return SafeCoTaskMemHandle.Null;
			if (value is IEnumerable<string> sa && (type.IsFlagSet(DEVPROPTYPE.DEVPROP_TYPEMOD_LIST) && (type.IsFlagSet(DEVPROPTYPE.DEVPROP_TYPE_STRING) || type.IsFlagSet(DEVPROPTYPE.DEVPROP_TYPE_SECURITY_DESCRIPTOR_STRING))))
				return SafeCoTaskMemHandle.CreateFromStringList(sa, StringListPackMethod.Concatenated, CharSet.Unicode);
			var valType = value.GetType();

			// Validate type of property against supplied type
			if (type.IsFlagSet(DEVPROPTYPE.DEVPROP_TYPEMOD_LIST))
				throw new ArgumentException("Invalid list.", nameof(value));
			if (type.IsFlagSet(DEVPROPTYPE.DEVPROP_TYPEMOD_ARRAY))
			{
				if (!valType.IsArray)
					throw new ArgumentException("Array required.", nameof(value));
				valType = valType.GetElementType()!;
				type &= DEVPROPTYPE.DEVPROP_MASK_TYPE;
			}
			var cTypes = CorrespondingTypeAttribute.GetCorrespondingTypes(type & DEVPROPTYPE.DEVPROP_MASK_TYPE).ToArray();
			if (cTypes.Length > 0 && Array.IndexOf(cTypes, valType) < 0)
				throw new ArgumentException($"Value type or element type cannot be {valType.Name}", nameof(value));

			// Push value into mem
			switch (value)
			{
				case byte[] ba:
					return new SafeCoTaskMemHandle(ba);

				case string s:
					return new SafeCoTaskMemHandle(s);

				default:
					var sz = InteropExtensions.SizeOf(valType);
					if (valType.IsArray) sz *= ((Array)value).Length;
					var mem = new SafeCoTaskMemHandle(sz);
					mem.DangerousGetHandle().Write(value, 0, mem.Size);
					return mem;
			}
		}

		/// <inheritdoc/>
		protected override void SetValue(DEVPROPKEY key, object? value)
		{
			value = CommonPropConv(value);
			var type = GetPropType(key, value?.GetType());
			var mem = PrepValue(value, type);
			try
			{
				if (mem is null)
					throw new ArgumentException("Unable to convert object to property type.", nameof(value));
				Win32Error.ThrowLastErrorIfFalse(SetupDiSetClassPropertyEx(Guid, key, type, mem.DangerousGetHandle(), mem.Size, DICLASSPROP.DICLASSPROP_INSTALLER, MachineName));
			}
			finally
			{
				mem?.Dispose();
			}
		}

		private DEVPROPTYPE GetPropType(DEVPROPKEY propKey, Type? valType)
		{
			if (SetupDiGetClassPropertyEx(Guid, propKey, out var type, default, default, out _, DICLASSPROP.DICLASSPROP_INSTALLER, MachineName))
				return type;
			var fi = typeof(DEVPROPTYPE).GetFields().Where(fi => fi.IsLiteral && fi.GetCustomAttributes<CorrespondingTypeAttribute>(false, a => a.TypeRef == valType).Any()).FirstOrDefault();
			return fi is not null ? (DEVPROPTYPE)fi.GetValue(null)! : throw new ArgumentException("Unable to determine DEVPROPTYPE.");
		}

		private Win32Error GetValue(in DEVPROPKEY propKey, out object? value)
		{
			value = null;
			if (!SetupDiGetClassPropertyEx(Guid, propKey, out _, default, 0, out var bufSz, DICLASSPROP.DICLASSPROP_INSTALLER, MachineName))
			{
				var err = Win32Error.GetLastError();
				if (err != Win32Error.ERROR_INSUFFICIENT_BUFFER)
					return err;
				using var mem = new SafeCoTaskMemHandle(bufSz);
				if (!SetupDiGetClassPropertyEx(Guid, propKey, out var propType, mem, mem.Size, out bufSz, DICLASSPROP.DICLASSPROP_INSTALLER, MachineName))
					return Win32Error.GetLastError();
				value = SetupDiPropertyToManagedObject(mem, propType, propKey.GetCorrespondingTypes().FirstOrDefault());
			}
			return Win32Error.ERROR_SUCCESS;
		}
	}

	/// <summary>Accesses registry properties with a device class.</summary>
	public class DeviceClassRegProperties : VirtualDictionary<SPCRP, object?>, IPropertyProvider<SPCRP, object?>
	{
		private readonly Guid Guid;

		private readonly string? MachineName;

		internal DeviceClassRegProperties(Guid guid, string? machineName) : base(false)
		{
			Guid = guid;
			MachineName = machineName;
		}

		private DeviceClassRegProperties() : base(false) => throw new InvalidOperationException();

		/// <inheritdoc/>
		public override int Count => Enum.GetValues(typeof(SPCRP)).Length;

		/// <inheritdoc/>
		public override ICollection<SPCRP> Keys => (ICollection<SPCRP>)Enum.GetValues(typeof(SPCRP));

		/// <inheritdoc/>
		public override bool Remove(SPCRP key) => SetupDiSetClassRegistryProperty(Guid, key, default, 0, MachineName);

		/// <inheritdoc/>
		public override bool TryGetValue(SPCRP key, [NotNullWhen(true)] out object? value) => (uint)GetValue(key, out value) is Win32Error.ERROR_SUCCESS or Win32Error.ERROR_NOT_FOUND;

		internal static object CommonPropConv(object value) => value switch
		{
			bool b => (BOOL)b,
			ISafeMemoryHandle h => h.GetBytes(0, h.Size),
			_ => value,
		};

		internal static object? GetRegValue<T>(T key, SafeAllocatedMemoryHandle mem, REG_VALUE_TYPE propType) where T : Enum => 
			GetRegValue(mem, propType, CorrespondingTypeAttribute.GetCorrespondingTypes(key).FirstOrDefault());

		internal static object? GetRegValue(SafeAllocatedMemoryHandle mem, REG_VALUE_TYPE propType, Type? cType = null) => propType switch
		{
			REG_VALUE_TYPE.REG_DWORD when cType is not null => ((IntPtr)mem).Convert(mem.Size, cType),
			REG_VALUE_TYPE.REG_BINARY when cType is not null && cType != typeof(byte[]) => ((IntPtr)mem).Convert(mem.Size, cType),
			_ => propType.GetValue(mem, mem.Size),
		};

		/// <inheritdoc/>
		protected override void SetValue(SPCRP key, object? value)
		{
			if (value is null)
				throw new ArgumentNullException(nameof(value));
			value = CommonPropConv(value);
			if (!CorrespondingTypeAttribute.CanSet(key, value.GetType()))
				throw new ArgumentException("Value type not valid for key.");
			SafeAllocatedMemoryHandle? mem = key switch
			{
				SPCRP.SPCRP_UPPERFILTERS => value is IEnumerable<string> uf ? SafeCoTaskMemHandle.CreateFromStringList(uf) : null,
				SPCRP.SPCRP_LOWERFILTERS => value is IEnumerable<string> lf ? SafeCoTaskMemHandle.CreateFromStringList(lf) : null,
				SPCRP.SPCRP_SECURITY => value is byte[] ba ? new SafeCoTaskMemHandle(ba) : null,
				SPCRP.SPCRP_SECURITY_SDS => value is string s ? new SafeCoTaskMemString(s, CharSet.Auto) : null,
				SPCRP.SPCRP_DEVTYPE => value is FILE_DEVICE fd ? SafeCoTaskMemHandle.CreateFromStructure(fd) : null,
				SPCRP.SPCRP_EXCLUSIVE => value is BOOL b ? SafeCoTaskMemHandle.CreateFromStructure(b) : null,
				SPCRP.SPCRP_CHARACTERISTICS => value is uint u ? SafeCoTaskMemHandle.CreateFromStructure(u) : null,
				_ => null,
			};
			try
			{
				if (mem is null)
					throw new ArgumentException("Unable to convert object to property type.", nameof(value));
				Win32Error.ThrowLastErrorIfFalse(SetupDiSetClassRegistryProperty(Guid, key, mem.DangerousGetHandle(), mem.Size, MachineName));
			}
			finally
			{
				mem?.Dispose();
			}
		}

		private Win32Error GetValue(SPCRP propKey, out object? value)
		{
			value = null;
			if (!SetupDiGetClassRegistryProperty(Guid, propKey, out _, default, 0, out var bufSz, MachineName))
			{
				_ = Win32Error.GetLastError();
				if (bufSz == 0)
					return Win32Error.ERROR_NOT_FOUND;
				using var mem = new SafeCoTaskMemHandle(bufSz);
				if (!SetupDiGetClassRegistryProperty(Guid, propKey, out var propType, mem, mem.Size, out bufSz, MachineName))
					return Win32Error.GetLastError();
				value = GetRegValue(propKey, mem, propType);
			}
			return Win32Error.ERROR_SUCCESS;
		}
	}

	private sealed class FinalizeImgLists
	{
		~FinalizeImgLists()
		{
			foreach (var val in imgListData.Values)
				SetupDiDestroyClassImageList(val);
		}
	}
}

/// <summary>A class that provides the collection of device setup classes available on a machine.</summary>
public class DeviceClassCollection : IReadOnlyCollection<DeviceClass>, IDisposable
{
	/// <summary>
	/// Initializes a new instance of the <see cref="DeviceClassCollection"/> class with the flags and machine name to be used by <see
	/// cref="SetupDiBuildClassInfoListEx"/> to retrieve the classes.
	/// </summary>
	/// <param name="flags">
	/// <para>
	/// Flags used to control exclusion of classes from the list. If no flags are specified, all setup classes are included in the list.
	/// Can be a combination of the following values:
	/// </para>
	/// <para>DIBCI_NOINSTALLCLASS</para>
	/// <para>Exclude a class if it has the <c>NoInstallClass</c> value entry in its registry key.</para>
	/// <para>DIBCI_NODISPLAYCLASS</para>
	/// <para>Exclude a class if it has the <c>NoDisplayClass</c> value entry in its registry key.</para>
	/// </param>
	/// <param name="machineName">
	/// A string that contains the name of a remote computer from which to retrieve installed setup classes. This parameter is optional
	/// and can be <see langword="null"/>. If MachineName is <see langword="null"/>, this class provides a list of classes installed on
	/// the local computer.
	/// </param>
	public DeviceClassCollection(DIBCI flags = 0, string? machineName = null)
	{
		Flags = flags;
		MachineName = machineName;
	}

	/// <summary>Gets the number of elements in the collection.</summary>
	/// <value>The number of elements in the collection.</value>
	public int Count
	{
		get
		{
			SetupDiBuildClassInfoListEx(Flags, null, 0, out var len, MachineName);
			return (int)len;
		}
	}

	/// <summary>
	/// Gets the flags used to control exclusion of classes from the list. If no flags are specified, all setup classes are included in
	/// the list.
	/// </summary>
	/// <value>
	/// Flags used to control exclusion of classes from the list. If no flags are specified, all setup classes are included in the list.
	/// </value>
	public DIBCI Flags { get; }

	/// <summary>Gets the name of the machine on which devices are managed. <see langword="null"/> indicates the local machine.</summary>
	/// <value>The machine name for this manager.</value>
	public string? MachineName { get; }

	// TODO
	//bool ICollection<DeviceClass>.IsReadOnly => false;
	//public void Add(DeviceClass item) => throw new NotImplementedException();
	//public void Clear() => throw new NotImplementedException();
	//public bool Contains(DeviceClass item) => throw new NotImplementedException();
	//public void CopyTo(DeviceClass[] array, int arrayIndex) => throw new NotImplementedException();
	//public bool Remove(DeviceClass item) => throw new NotImplementedException();

	/// <summary>Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.</summary>
	public void Dispose()
	{
	}

	/// <summary>Returns an enumerator that iterates through the collection.</summary>
	/// <returns>A <see cref="T:System.Collections.Generic.IEnumerator`1"/> that can be used to iterate through the collection.</returns>
	public IEnumerator<DeviceClass> GetEnumerator()
	{
		SetupDiBuildClassInfoListEx(Flags, null, 0, out var len, MachineName);
		if (len == 0) Win32Error.ThrowLastError();

		var guids = new Guid[(int)len];
		Win32Error.ThrowLastErrorIfFalse(SetupDiBuildClassInfoListEx(Flags, guids, len, out _, MachineName));
		for (int i = 0; i < len; i++)
			yield return new DeviceClass(guids[i], MachineName);
	}

	/// <summary>Returns an enumerator that iterates through a collection.</summary>
	/// <returns>An <see cref="T:System.Collections.IEnumerator"/> object that can be used to iterate through the collection.</returns>
	IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
}

/// <summary>A class that provides the collection of devices available on a machine.</summary>
/// <seealso cref="System.Collections.Generic.IEnumerable{T}"/>
/// <seealso cref="System.IDisposable"/>
public class DeviceCollection : IEnumerable<Device>, IDisposable
{
	private SafeHDEVINFO devInfoSet;

	/// <summary>Initializes a new instance of the <see cref="DeviceCollection"/> class.</summary>
	/// <param name="classGuid">
	/// The GUID for a device setup class or a device interface class. This value is optional and can be <see langword="null"/>. If a
	/// GUID value is not used to select devices, set <paramref name="classGuid"/> to <see langword="null"/>.
	/// </param>
	/// <param name="enumerator">
	/// <para>A string that specifies:</para>
	/// <list type="bullet">
	/// <item>
	/// <term>
	/// An identifier (ID) of a Plug and Play (PnP) enumerator. This ID can either be the enumerator's globally unique identifier (GUID)
	/// or symbolic name. For example, "PCI" can be used to specify the PCI PnP enumerator. Other examples of symbolic names for PnP
	/// enumerators include "USB", "PCMCIA", and "SCSI".
	/// </term>
	/// </item>
	/// <item>
	/// <term>
	/// A PnP device instance IDs. When specifying a PnP device instance ID, DIGCF_DEVICEINTERFACE must be set in the <see
	/// cref="Filter"/> property.
	/// </term>
	/// </item>
	/// </list>
	/// <para>This value is optional and can be <see langword="null"/>.</para>
	/// </param>
	/// <param name="machineName">
	/// A string that contains the name of a remote computer on which the devices reside. A value of <see langword="null"/> for
	/// <paramref name="machineName"/> specifies that the device is installed on the local computer.
	/// </param>
	/// <param name="filter">
	/// Specifies control options that filter the device information elements that are added to the device information set. This
	/// property can be a bitwise OR of one or more of the <see cref="DIGCF"/> flags.
	/// </param>
	public DeviceCollection(Guid? classGuid = null, string? enumerator = null, string? machineName = null, DIGCF filter = DIGCF.DIGCF_PRESENT)
	{
		ClassGuid = classGuid;
		PnPEnumeratorOrDevInstId = enumerator;
		MachineName = machineName;
		Filter = PnPEnumeratorOrDevInstId is null ? filter : filter.SetFlags(DIGCF.DIGCF_DEVICEINTERFACE, PnPEnumeratorOrDevInstId.Contains("\\"));
		Reset();
	}

	/// <summary>Gets the GUID for the device's setup class or interface class. This value is optional and may be <see langword="null"/>.</summary>
	/// <value>The GUID for the device's setup class or interface class. This value is optional and may be <see langword="null"/>.</value>
	public Guid? ClassGuid { get; }

	/// <summary>
	/// Gets a value that specifies control options that filter the device information elements that are added to the device information
	/// set. This property can be a bitwise OR of one or more of the <see cref="DIGCF"/> flags.
	/// </summary>
	/// <value>The filter options.</value>
	public DIGCF Filter { get; }

	/// <summary>
	/// Gets the name of a remote computer on which the devices reside. A value of <see langword="null"/> specifies that the device is
	/// installed on the local computer.
	/// </summary>
	/// <value>
	/// The name of a remote computer on which the devices reside. A value of <see langword="null"/> specifies that the device is
	/// installed on the local computer.
	/// </value>
	public string? MachineName { get; }

	/// <summary>
	/// <para>Gets a string that specifies:</para>
	/// <list type="bullet">
	/// <item>
	/// <term>
	/// An identifier (ID) of a Plug and Play (PnP) enumerator. This ID can either be the enumerator's globally unique identifier (GUID)
	/// or symbolic name. For example, "PCI" can be used to specify the PCI PnP enumerator. Other examples of symbolic names for PnP
	/// enumerators include "USB", "PCMCIA", and "SCSI".
	/// </term>
	/// </item>
	/// <item>
	/// <term>
	/// A PnP device instance IDs. When specifying a PnP device instance ID, DIGCF_DEVICEINTERFACE must be set in the <see
	/// cref="Filter"/> property.
	/// </term>
	/// </item>
	/// </list>
	/// <para>This value is optional and can be <see langword="null"/>.</para>
	/// </summary>
	/// <value>The PnP enumerator or device instance ID.</value>
	public string? PnPEnumeratorOrDevInstId { get; }

	/// <summary>Releases unmanaged and - optionally - managed resources.</summary>
	public void Dispose() { }

	/// <inheritdoc/>
	public IEnumerator<Device> GetEnumerator()
	{
		var data = StructHelper.InitWithSize<SP_DEVINFO_DATA>();
		for (uint i = 0; SetupDiEnumDeviceInfo(devInfoSet, i, ref data); i++)
			yield return new Device(devInfoSet, data);
		Win32Error.ThrowLastErrorUnless(Win32Error.ERROR_NO_MORE_ITEMS);
	}

	/// <inheritdoc/>
	IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();

	[MemberNotNull(nameof(devInfoSet))]
	private void Reset()
	{
		devInfoSet?.Dispose();
		devInfoSet = SafeHDEVINFO.Create(ClassGuid, Filter, PnPEnumeratorOrDevInstId, MachineName);
		Win32Error.ThrowLastErrorIfInvalid(devInfoSet);
	}
}

/// <summary>Class to manage local and remote devices.</summary>
public class DeviceManager
{
	private static readonly Lazy<DeviceManager> local = new(() => new DeviceManager(null));

	/// <summary>Initializes a new instance of the <see cref="DeviceManager"/> class on a specified machine.</summary>
	/// <param name="machineName">Name of the machine on which to manage devices. Specify <see langword="null"/> for the local machine.</param>
	public DeviceManager(string? machineName = null) => MachineName = machineName;

	/// <summary>Provides access to the local machine's devices.</summary>
	public static DeviceManager LocalInstance => local.Value;

	/// <summary>Gets the name of the machine on which devices are managed. <see langword="null"/> indicates the local machine.</summary>
	/// <value>The machine name for this manager.</value>
	public string? MachineName { get; }

	/// <summary>Gets the devices associated with this machine.</summary>
	/// <param name="filter">
	/// Specifies control options that filter the device information elements that are added to the device information set. This
	/// property can be a bitwise OR of one or more of the <see cref="DIGCF"/> flags.
	/// </param>
	/// <returns>A sequence of <see cref="Device"/> instances on this machine.</returns>
	public IEnumerable<Device> GetDevices(DIGCF filter = DIGCF.DIGCF_PRESENT) => new DeviceCollection(null, null, MachineName, filter);

	/// <summary>Gets the setup classes available on the machine.</summary>
	/// <value>A class that provides the collection of setup classes.</value>
	public IEnumerable<DeviceClass> GetSetupClasses() => new DeviceClassCollection(0, MachineName);
}

// TODO
internal class DeviceInterface
{
}