Native.cs

using System;
using System.Runtime.InteropServices;

namespace Snapper
{
    /// <summary>
    /// Most code based on code from http://pinvoke.net/default.aspx.
    /// 
    /// See http://pinvoke.net/termsofuse.htm for license.
    /// </summary>
    public static class Native
    {
        [StructLayout(LayoutKind.Sequential)]
        public struct RECT
        {
            public int Left, Top, Right, Bottom;

            public RECT(int left, int top, int right, int bottom)
            {
                Left = left;
                Top = top;
                Right = right;
                Bottom = bottom;
            }

            public RECT(System.Drawing.Rectangle r) : this(r.Left, r.Top, r.Right, r.Bottom) { }

            public int X
            {
                get { return Left; }
                set { Right -= (Left - value); Left = value; }
            }

            public int Y
            {
                get { return Top; }
                set { Bottom -= (Top - value); Top = value; }
            }

            public int Height
            {
                get { return Bottom - Top; }
                set { Bottom = value + Top; }
            }

            public int Width
            {
                get { return Right - Left; }
                set { Right = value + Left; }
            }

            public System.Drawing.Point Location
            {
                get { return new System.Drawing.Point(Left, Top); }
                set { X = value.X; Y = value.Y; }
            }

            public System.Drawing.Size Size
            {
                get { return new System.Drawing.Size(Width, Height); }
                set { Width = value.Width; Height = value.Height; }
            }

            public static implicit operator System.Drawing.Rectangle(RECT r)
            {
                return new System.Drawing.Rectangle(r.Left, r.Top, r.Width, r.Height);
            }

            public static implicit operator RECT(System.Drawing.Rectangle r)
            {
                return new RECT(r);
            }

            public static bool operator ==(RECT r1, RECT r2)
            {
                return r1.Equals(r2);
            }

            public static bool operator !=(RECT r1, RECT r2)
            {
                return !r1.Equals(r2);
            }

            public bool Equals(RECT r)
            {
                return r.Left == Left && r.Top == Top && r.Right == Right && r.Bottom == Bottom;
            }

            public override bool Equals(object obj)
            {
                if (obj is RECT)
                    return Equals((RECT)obj);
                else if (obj is System.Drawing.Rectangle)
                    return Equals(new RECT((System.Drawing.Rectangle)obj));
                return false;
            }

            public override int GetHashCode()
            {
                return ((System.Drawing.Rectangle)this).GetHashCode();
            }

            public override string ToString()
            {
                return string.Format(System.Globalization.CultureInfo.CurrentCulture, "{{Left={0},Top={1},Right={2},Bottom={3}}}", Left, Top, Right, Bottom);
            }
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct POINT
        {
            public int X;
            public int Y;

            public POINT(int x, int y)
            {
                this.X = x;
                this.Y = y;
            }

            public static implicit operator System.Drawing.Point(POINT p)
            {
                return new System.Drawing.Point(p.X, p.Y);
            }

            public static implicit operator POINT(System.Drawing.Point p)
            {
                return new POINT(p.X, p.Y);
            }

            public override string ToString()
            {
                return string.Format(System.Globalization.CultureInfo.CurrentCulture, "{{X={0},Y={1}}}", X, Y);
            }
        }


        // Not all SWP_* values are here as we only need a few of them.
        public const uint SWP_ASYNCWINDOWPOS = 0x4000;
        public const uint SWP_NOCOPYBITS = 0x0100;

        // Same for SW_* values as above.
        public const int SW_RESTORE = 9;

        // Same for WM_* values as above.
        public const int WM_HOTKEY = 0x0312;

        [return: MarshalAs(UnmanagedType.Bool)]
        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern bool RegisterHotKey(IntPtr hWnd, int id, int fsModifiers, int vk);

        [return: MarshalAs(UnmanagedType.Bool)]
        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern bool UnregisterHotKey(IntPtr hWnd, int id);

        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern IntPtr GetForegroundWindow();

        [return: MarshalAs(UnmanagedType.Bool)]
        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern bool SetWindowPos(IntPtr hWnd, IntPtr hWndInsertAfter, int x, int y, int cx, int cy, uint uFlags);

        [return: MarshalAs(UnmanagedType.Bool)]
        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern bool GetClientRect(IntPtr hWnd, out RECT lpRect);

        [return: MarshalAs(UnmanagedType.Bool)]
        [DllImport("user32.dll")]
        public static extern bool GetWindowRect(IntPtr hwnd, out RECT lpRect);

        [return: MarshalAs(UnmanagedType.Bool)]
        [DllImport("user32.dll")]
        public static extern bool ScreenToClient(IntPtr hWnd, ref POINT lpPoint);

        [return: MarshalAs(UnmanagedType.Bool)]
        [DllImport("user32.dll")]
        public static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
    }
}