using Microsoft.SharePoint.Administration;
using System;
using System.Runtime.InteropServices;
namespace SPSolutions.SharePoint.Logging
{
	public static class TraceProvider
	{
		private static class NativeMethods
		{
			internal enum TraceFlags
			{
				TRACE_FLAG_START = 1,
				TRACE_FLAG_END,
				TRACE_FLAG_MIDDLE,
				TRACE_FLAG_ID_AS_ASCII
			}
			internal struct EVENT_TRACE_HEADER_CLASS
			{
				internal byte Type;
				internal byte Level;
				internal ushort Version;
			}
			internal struct EVENT_TRACE_HEADER
			{
				internal ushort Size;
				internal ushort FieldTypeFlags;
				internal TraceProvider.NativeMethods.EVENT_TRACE_HEADER_CLASS Class;
				internal uint ThreadId;
				internal uint ProcessId;
				internal long TimeStamp;
				internal Guid Guid;
				internal uint ClientContext;
				internal uint Flags;
			}
			[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
			internal struct ULSTraceHeader
			{
				internal ushort Size;
				internal uint dwVersion;
				internal uint Id;
				internal Guid correlationID;
				internal TraceProvider.NativeMethods.TraceFlags dwFlags;
				[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
				internal string wzExeName;
				[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
				internal string wzProduct;
				[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
				internal string wzCategory;
				[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 800)]
				internal string wzMessage;
			}
			internal struct ULSTrace
			{
				internal TraceProvider.NativeMethods.EVENT_TRACE_HEADER Header;
				internal TraceProvider.NativeMethods.ULSTraceHeader ULSHeader;
			}
			internal enum WMIDPREQUESTCODE
			{
				WMI_GET_ALL_DATA,
				WMI_GET_SINGLE_INSTANCE,
				WMI_SET_SINGLE_INSTANCE,
				WMI_SET_SINGLE_ITEM,
				WMI_ENABLE_EVENTS,
				WMI_DISABLE_EVENTS,
				WMI_ENABLE_COLLECTION,
				WMI_DISABLE_COLLECTION,
				WMI_REGINFO,
				WMI_EXECUTE_METHOD
			}
			internal unsafe delegate uint EtwProc(TraceProvider.NativeMethods.WMIDPREQUESTCODE requestCode, IntPtr requestContext, uint* bufferSize, IntPtr buffer);
			internal const int TRACE_VERSION_CURRENT = 1;
			internal const int ERROR_SUCCESS = 0;
			internal const int ERROR_INVALID_PARAMETER = 87;
			internal const int WNODE_FLAG_TRACED_GUID = 131072;
			[DllImport("advapi32.dll", CharSet = CharSet.Unicode)]
			internal unsafe static extern uint RegisterTraceGuids([In] TraceProvider.NativeMethods.EtwProc cbFunc, [In] void* context, [In] ref Guid controlGuid, [In] uint guidCount, IntPtr guidReg, [In] string mofImagePath, [In] string mofResourceName, out ulong regHandle);
			[DllImport("advapi32.dll", CharSet = CharSet.Unicode)]
			internal static extern uint UnregisterTraceGuids([In] ulong regHandle);
			[DllImport("advapi32.dll", CharSet = CharSet.Unicode)]
			internal static extern ulong GetTraceLoggerHandle([In] IntPtr Buffer);
			[DllImport("advapi32.dll", SetLastError = true)]
			internal static extern uint TraceEvent([In] ulong traceHandle, [In] ref TraceProvider.NativeMethods.ULSTrace evnt);
		}
		public enum TraceSeverity
		{
			Unassigned,
			CriticalEvent,
			WarningEvent,
			InformationEvent,
			Exception,
			Assert = 7,
			Unexpected = 10,
			Monitorable = 15,
			High = 20,
			Medium = 50,
			Verbose = 100
		}
		private static ulong hTraceLog;
		private static ulong hTraceReg;
		public static void WriteTrace(uint tag, TraceProvider.TraceSeverity level, Guid correlationGuid, string exeName, string productName, string categoryName, string message)
		{
			TraceProvider.NativeMethods.ULSTrace uLSTrace = default(TraceProvider.NativeMethods.ULSTrace);
			uLSTrace.Header.Size = (ushort)Marshal.SizeOf(typeof(TraceProvider.NativeMethods.ULSTrace));
			uLSTrace.Header.Flags = 131072u;
			uLSTrace.ULSHeader.dwVersion = 1u;
			uLSTrace.ULSHeader.dwFlags = TraceProvider.NativeMethods.TraceFlags.TRACE_FLAG_ID_AS_ASCII;
			uLSTrace.ULSHeader.Size = (ushort)Marshal.SizeOf(typeof(TraceProvider.NativeMethods.ULSTraceHeader));
			uLSTrace.ULSHeader.Id = tag;
			uLSTrace.Header.Class.Level = (byte)level;
			uLSTrace.ULSHeader.wzExeName = exeName;
			uLSTrace.ULSHeader.wzProduct = productName;
			uLSTrace.ULSHeader.wzCategory = categoryName;
			uLSTrace.ULSHeader.wzMessage = message;
			uLSTrace.ULSHeader.correlationID = correlationGuid;
			if (message.Length < 800)
			{
				ushort num = (ushort)((800 - (message.Length + 1)) * 2);
                uLSTrace.Header.Size = (ushort)(uLSTrace.Header.Size - num);
                uLSTrace.ULSHeader.Size = (ushort)(uLSTrace.ULSHeader.Size - num);
			}
			if (TraceProvider.hTraceLog != 0uL)
			{
				TraceProvider.NativeMethods.TraceEvent(TraceProvider.hTraceLog, ref uLSTrace);
			}
		}
		public static void WriteMultiLineTrace(uint tag, TraceProvider.TraceSeverity level, Guid correlationGuid, string exeName, string productName, string categoryName, string message)
		{
			int num = 700;
			int i = 0;
			int num2 = 1;
			if (message.Length <= num)
			{
				TraceProvider.WriteTrace(tag, level, correlationGuid, exeName, productName, categoryName, message);
				return;
			}
			TraceProvider.WriteTrace(tag, level, correlationGuid, exeName, productName, categoryName, string.Format("{0}", message.Substring(i, num)));
			int num3;
			for (i = num + 1; i < message.Length; i += num3)
			{
				if (message.Length - i >= num)
				{
					num3 = num;
				}
				else
				{
					num3 = message.Length - i;
				}
				TraceProvider.WriteTrace(tag, level, correlationGuid, exeName, productName, categoryName, string.Format("{0}...{1}", num2, message.Substring(i, num3)));
				num2++;
			}
		}
		public static void WriteMultiLineTrace(uint tag, TraceProvider.TraceSeverity level, Guid correlationGuid, string exeName, string productName, string categoryName, string lineheader, string message)
		{
			int num = 700;
			int i = 0;
			int num2 = 1;
			if (message.Length <= num)
			{
				TraceProvider.WriteTrace(tag, level, correlationGuid, exeName, productName, categoryName, message);
				return;
			}
			TraceProvider.WriteTrace(tag, level, correlationGuid, exeName, productName, categoryName, string.Format("{0}0...{1}", lineheader, message.Substring(i, num)));
			int num3;
			for (i = num + 1; i < message.Length; i += num3)
			{
				if (message.Length - i >= num)
				{
					num3 = num;
				}
				else
				{
					num3 = message.Length - i;
				}
				TraceProvider.WriteTrace(tag, level, correlationGuid, exeName, productName, categoryName, string.Format("{0}{1}...{2}", lineheader, num2, message.Substring(i, num3)));
				num2++;
			}
		}
		public static void RegisterTraceProvider()
		{
			SPFarm local = SPFarm.Local;
			Guid traceSessionGuid = local.TraceSessionGuid;
            unsafe
            {
                TraceProvider.NativeMethods.RegisterTraceGuids(new TraceProvider.NativeMethods.EtwProc(TraceProvider.ControlCallback), null, ref traceSessionGuid, 0u, IntPtr.Zero, null, null, out TraceProvider.hTraceReg);
            }
		}
		public static void UnregisterTraceProvider()
		{
			TraceProvider.NativeMethods.UnregisterTraceGuids(TraceProvider.hTraceReg);
		}
		public static uint TagFromString(string wzTag)
		{
			return (uint)((uint)wzTag[0] << 24 | (uint)wzTag[1] << 16 | (uint)wzTag[2] << 8 | wzTag[3]);
		}
		private unsafe static uint ControlCallback(TraceProvider.NativeMethods.WMIDPREQUESTCODE RequestCode, IntPtr Context, uint* InOutBufferSize, IntPtr Buffer)
		{
			uint result;
			switch (RequestCode)
			{
			case TraceProvider.NativeMethods.WMIDPREQUESTCODE.WMI_ENABLE_EVENTS:
				TraceProvider.hTraceLog = TraceProvider.NativeMethods.GetTraceLoggerHandle(Buffer);
				result = 0u;
				break;
			case TraceProvider.NativeMethods.WMIDPREQUESTCODE.WMI_DISABLE_EVENTS:
				TraceProvider.hTraceLog = 0uL;
				result = 0u;
				break;
			default:
				result = 87u;
				break;
			}
			*InOutBufferSize = 0u;
			return result;
		}
	}
}