TweetDuck/Utils/NativeMethods.cs

using System;
using System.Diagnostics.CodeAnalysis;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace TweetDuck.Utils {
	[SuppressMessage("ReSharper", "FieldCanBeMadeReadOnly.Local")]
	[SuppressMessage("ReSharper", "MemberCanBePrivate.Local")]
	[SuppressMessage("ReSharper", "InconsistentNaming")]
	static class NativeMethods {
		public static readonly IntPtr HWND_BROADCAST = new IntPtr(0xFFFF);
		public static readonly IntPtr HOOK_HANDLED = new IntPtr(-1);

		public const int HWND_TOPMOST = -1;
		public const uint SWP_NOACTIVATE = 0x0010;
		public const int WS_DISABLED = 0x08000000;
		public const int GWL_STYLE = -16;

		public const int SB_HORZ = 0;
		public const int EM_SETCUEBANNER = 0x1501;

		public const int WM_MOUSE_LL = 14;
		public const int WM_MOUSEWHEEL = 0x020A;
		public const int WM_XBUTTONDOWN = 0x020B;
		public const int WM_XBUTTONUP = 0x020C;
		public const int WM_PARENTNOTIFY = 0x0210;

		[StructLayout(LayoutKind.Sequential)]
		[SuppressMessage("ReSharper", "InconsistentNaming")]
		private struct LASTINPUTINFO {
			public static readonly uint Size = (uint) Marshal.SizeOf(typeof(LASTINPUTINFO));

			public uint cbSize;
			public uint dwTime;
		}

		[StructLayout(LayoutKind.Sequential)]
		[SuppressMessage("ReSharper", "InconsistentNaming")]
		private struct POINT {
			public int X;
			public int Y;
		}

		[StructLayout(LayoutKind.Sequential)]
		[SuppressMessage("ReSharper", "InconsistentNaming")]
		private struct MSLLHOOKSTRUCT {
			public POINT pt;
			public int mouseData;
			public int flags;
			public int time;
			public UIntPtr dwExtraInfo;
		}

		public delegate IntPtr HookProc(int nCode, IntPtr wParam, IntPtr lParam);

		[DllImport("user32.dll", EntryPoint = "SetWindowPos")]
		private static extern bool SetWindowPos(int hWnd, int hWndOrder, int x, int y, int width, int height, uint flags);

		[DllImport("user32.dll")]
		public static extern bool SendMessage(IntPtr hWnd, int msg, int wParam, [MarshalAs(UnmanagedType.LPWStr)] string lParam);

		[DllImport("user32.dll")]
		public static extern bool PostMessage(IntPtr hWnd, uint msg, UIntPtr wParam, IntPtr lParam);

		[DllImport("user32.dll")]
		public static extern uint RegisterWindowMessage(string messageName);

		[DllImport("user32.dll")]
		private static extern bool GetLastInputInfo(ref LASTINPUTINFO info);

		[DllImport("user32.dll")]
		[return: MarshalAs(UnmanagedType.Bool)]
		public static extern bool ShowScrollBar(IntPtr hWnd, int wBar, bool bShow);

		[DllImport("user32.dll")]
		public static extern IntPtr SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);

		[DllImport("user32.dll")]
		public static extern bool UnhookWindowsHookEx(IntPtr idHook);

		[DllImport("user32.dll")]
		public static extern IntPtr CallNextHookEx(IntPtr idHook, int nCode, IntPtr wParam, IntPtr lParam);

		[DllImport("user32.dll")]
		private static extern int GetWindowLong(IntPtr hWnd, int nIndex);

		[DllImport("user32.dll")]
		private static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);

		public static void SetFormPos(Form form, int hWndOrder, uint flags) {
			SetWindowPos(form.Handle.ToInt32(), hWndOrder, form.Left, form.Top, form.Width, form.Height, flags);
		}

		public static void SetFormDisabled(Form form, bool disabled) {
			if (disabled) {
				SetWindowLong(form.Handle, GWL_STYLE, GetWindowLong(form.Handle, GWL_STYLE) | WS_DISABLED);
			}
			else {
				SetWindowLong(form.Handle, GWL_STYLE, GetWindowLong(form.Handle, GWL_STYLE) & ~WS_DISABLED);
			}
		}

		public static void BroadcastMessage(uint msg, uint wParam, int lParam) {
			PostMessage(HWND_BROADCAST, msg, new UIntPtr(wParam), new IntPtr(lParam));
		}

		public static int GetMouseHookData(IntPtr ptr) {
			return Marshal.PtrToStructure<MSLLHOOKSTRUCT>(ptr).mouseData >> 16;
		}

		public static int GetIdleSeconds() {
			LASTINPUTINFO info = new LASTINPUTINFO {
				cbSize = LASTINPUTINFO.Size
			};

			if (!GetLastInputInfo(ref info)) {
				return 0;
			}

			uint ticks;

			unchecked {
				ticks = (uint) Environment.TickCount;
			}

			int seconds = (int) Math.Floor(TimeSpan.FromMilliseconds(ticks - info.dwTime).TotalSeconds);
			return Math.Max(0, seconds); // ignore rollover after several weeks of uptime
		}
	}
}