// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
// If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// Copyright (C) LibreHardwareMonitor and Contributors.
// All Rights Reserved.

using System;
using System.Runtime.InteropServices;

// ReSharper disable InconsistentNaming

namespace LibreHardwareMonitor.Interop;

internal class NtDll
{
    private const string DllName = "ntdll";

    [StructLayout(LayoutKind.Sequential)]
    internal struct SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION
    {
        public long IdleTime;
        public long KernelTime;
        public long UserTime;
        public long Reserved0;
        public long Reserved1;
        public ulong Reserved2;
    }

    internal enum SYSTEM_INFORMATION_CLASS
    {
        SystemBasicInformation,
        SystemProcessorInformation,
        SystemPerformanceInformation,
        SystemTimeOfDayInformation,
        SystemPathInformation,
        SystemProcessInformation,
        SystemCallCountInformation,
        SystemDeviceInformation,
        SystemProcessorPerformanceInformation,
        SystemFlagsInformation,
        SystemCallTimeInformation,
        SystemModuleInformation,
        SystemLocksInformation,
        SystemStackTraceInformation,
        SystemPagedPoolInformation,
        SystemNonPagedPoolInformation,
        SystemHandleInformation,
        SystemObjectInformation,
        SystemPageFileInformation,
        SystemVdmInstemulInformation,
        SystemVdmBopInformation,
        SystemFileCacheInformation,
        SystemPoolTagInformation,
        SystemInterruptInformation,
        SystemDpcBehaviorInformation,
        SystemFullMemoryInformation,
        SystemLoadGdiDriverInformation,
        SystemUnloadGdiDriverInformation,
        SystemTimeAdjustmentInformation,
        SystemSummaryMemoryInformation,
        SystemNextEventIdInformation,
        SystemEventIdsInformation,
        SystemCrashDumpInformation,
        SystemExceptionInformation,
        SystemCrashDumpStateInformation,
        SystemKernelDebuggerInformation,
        SystemContextSwitchInformation,
        SystemRegistryQuotaInformation,
        SystemExtendServiceTableInformation,
        SystemPrioritySeperation,
        SystemPlugPlayBusInformation,
        SystemDockInformation,
        SystemPowerInformation,
        SystemProcessorSpeedInformation,
        SystemCurrentTimeZoneInformation,
        SystemLookasideInformation
    }

    [DllImport(DllName)]
    [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
    internal static extern int NtQuerySystemInformation(SYSTEM_INFORMATION_CLASS SystemInformationClass, [Out] SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION[] SystemInformation, int SystemInformationLength, out IntPtr ReturnLength);
}