NativeMethods.cs

using System.Runtime.InteropServices;

namespace ZeroWubiLens;

internal static class NativeMethods
{
    // ---- structs ----
    [StructLayout(LayoutKind.Sequential)]
    public struct POINT
    {
        public int X;
        public int Y;
        public POINT(int x, int y) { X = x; Y = y; }
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct RECT
    {
        public int Left, Top, Right, Bottom;
        public int Width => Right - Left;
        public int Height => Bottom - Top;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct MONITORINFO
    {
        public int cbSize;
        public RECT rcMonitor;
        public RECT rcWork;
        public uint dwFlags;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct GUITHREADINFO
    {
        public int cbSize;
        public uint flags;
        public IntPtr hwndActive;
        public IntPtr hwndFocus;
        public IntPtr hwndCapture;
        public IntPtr hwndMenuOwner;
        public IntPtr hwndMoveSize;
        public IntPtr hwndCaret;
        public RECT rcCaret;
    }

    // ---- window styles ----
    public const int GWL_EXSTYLE = -20;
    public const int WS_EX_NOACTIVATE = 0x08000000;
    public const int WS_EX_TOOLWINDOW = 0x00000080;
    public const int WS_EX_TOPMOST = 0x00000008;
    public const int WS_EX_TRANSPARENT = 0x00000020;

    // ---- SetWindowPos ----
    public static readonly IntPtr HWND_TOPMOST = new(-1);
    public const uint SWP_NOSIZE = 0x0001;
    public const uint SWP_NOACTIVATE = 0x0010;
    public const uint SWP_SHOWWINDOW = 0x0040;
    public const uint SWP_NOZORDER = 0x0004;

    public const uint MONITOR_DEFAULTTONEAREST = 2;
    public const int MDT_EFFECTIVE_DPI = 0;

    // ---- P/Invoke ----
    [DllImport("user32.dll", SetLastError = true)]
    public static extern int GetWindowLong(IntPtr hWnd, int nIndex);

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

    [DllImport("user32.dll", SetLastError = true)]
    public static extern bool SetWindowPos(IntPtr hWnd, IntPtr hWndInsertAfter,
        int X, int Y, int cx, int cy, uint uFlags);

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

    [DllImport("user32.dll")]
    public static extern bool GetCursorPos(out POINT lpPoint);

    [DllImport("user32.dll")]
    public static extern IntPtr MonitorFromPoint(POINT pt, uint dwFlags);

    [DllImport("user32.dll", CharSet = CharSet.Unicode)]
    public static extern bool GetMonitorInfo(IntPtr hMonitor, ref MONITORINFO lpmi);

    [DllImport("user32.dll")]
    public static extern uint GetWindowThreadProcessId(IntPtr hWnd, IntPtr processId);

    [DllImport("user32.dll")]
    public static extern bool GetGUIThreadInfo(uint idThread, ref GUITHREADINFO lpgui);

    [DllImport("shcore.dll")]
    public static extern int GetDpiForMonitor(IntPtr hmonitor, int dpiType,
        out uint dpiX, out uint dpiY);
}