Class Native

loader/Main/Native.cs:6–49

namespace PenguLoader.Main
{
    static class Native
    {
        public static IntPtr SetWindowLongPtr(IntPtr hWnd, int nIndex, IntPtr dwNewLong)
        {
            return IntPtr.Size == 8
                ? SetWindowLongPtr64(hWnd, nIndex, dwNewLong)
                : new IntPtr(SetWindowLong32(hWnd, nIndex, dwNewLong.ToInt32()));
        }

        public static IntPtr GetWindowLongPtr(IntPtr hWnd, int nIndex)
        {
            return IntPtr.Size == 8
                ? GetWindowLongPtr64(hWnd, nIndex)
                : GetWindowLongPtr32(hWnd, nIndex);
        }

        public static void SetFocusToPreviousInstance()
        {
            PostMessage((IntPtr)HWND_BROADCAST, WM_SHOWME, IntPtr.Zero, IntPtr.Zero);
        }

        const int HWND_BROADCAST = 0xFFFF;

        public static readonly int WM_SHOWME = RegisterWindowMessage(Program.Name);

        [DllImport("user32.dll", EntryPoint = "SetWindowLong")]
        static extern int SetWindowLong32(IntPtr hWnd, int nIndex, int dwNewLong);

        [DllImport("user32.dll", EntryPoint = "SetWindowLongPtr")]
        static extern IntPtr SetWindowLongPtr64(IntPtr hWnd, int nIndex, IntPtr dwNewLong);

        [DllImport("user32.dll", EntryPoint = "GetWindowLong")]
        private static extern IntPtr GetWindowLongPtr32(IntPtr hWnd, int nIndex);

        [DllImport("user32.dll", EntryPoint = "GetWindowLongPtr")]
        private static extern IntPtr GetWindowLongPtr64(IntPtr hWnd, int nIndex);

        [DllImport("user32.dll", EntryPoint = "RegisterWindowMessageW", CharSet = CharSet.Unicode)]
        static extern int RegisterWindowMessage(string message);

        [DllImport("user32.dll", EntryPoint = "PostMessageW")]
        [return: MarshalAs(UnmanagedType.Bool)]
        static extern bool PostMessage(IntPtr hwnd, int msg, IntPtr wparam, IntPtr lparam);
    }
}