fixed bug - careet in notepad and menu start OS

CursorLang/Interop/CaretNative.cs

@@ -15,29 +15,6 @@ namespace CursorLang.Interop;
 /// </remarks>
 internal static class CaretNative
 {
-    [StructLayout(LayoutKind.Sequential)]
-    private 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 PopupWindowNative.Rect rcCaret;
-    }
-
-    [DllImport("user32.dll")]
-    private static extern bool GetGUIThreadInfo(uint idThread, ref GuiThreadInfo lpgui);
-
-    [DllImport("user32.dll")]
-    private static extern IntPtr GetForegroundWindow();
-
-    [DllImport("user32.dll")]
-    private static extern uint GetWindowThreadProcessId(IntPtr hWnd, IntPtr lpdwProcessId);
-
     [DllImport("user32.dll")]
     private static extern bool ClientToScreen(IntPtr hWnd, ref PopupWindowNative.Point lpPoint);
 
@@ -45,6 +22,12 @@ internal static class CaretNative
     private static extern int AccessibleObjectFromWindow(IntPtr hwnd, uint dwObjectId,
         ref Guid riid, out IAccessible ppvObject);
 
+    [DllImport("user32.dll")]
+    private static extern bool GetWindowRect(IntPtr hWnd, out PopupWindowNative.Rect lpRect);
+
+    [DllImport("user32.dll")]
+    private static extern uint GetDpiForWindow(IntPtr hWnd);
+
     private const uint OBJID_CARET = 0xFFFFFFF8;
     private const int CHILDID_SELF = 0;
 
@@ -54,18 +37,55 @@ internal static class CaretNative
     /// </summary>
     internal static PopupWindowNative.Rect? TryGetCaretRect()
     {
-        var info = new GuiThreadInfo { cbSize = Marshal.SizeOf<GuiThreadInfo>() };
-        uint threadId = GetWindowThreadProcessId(GetForegroundWindow(), IntPtr.Zero);
-        if (!GetGUIThreadInfo(threadId, ref info))
+        if (!ForegroundInputNative.TryGetInfo(out ForegroundInputNative.GuiThreadInfo info))
         {
             return null;
         }
 
-        return TryGetSystemCaret(info)
+        PopupWindowNative.Rect? caret = TryGetSystemCaret(info)
             ?? TryGetAccessibleCaret(info.hwndFocus)
             ?? TryGetAutomationCaret();
+
+        return caret is null ? null : Validate(caret.Value, info.hwndFocus);
     }
 
+    /// <summary>
+    /// Отсеивает заведомо неверные координаты.
+    /// </summary>
+    /// <remarks>
+    /// Часть приложений отдаёт положение каретки в своей системе координат либо
+    /// без учёта масштаба экрана, и подсказка уезжает далеко от поля ввода.
+    /// Каретка обязана находиться внутри окна ввода — это и проверяем, а перед
+    /// отказом пробуем истолковать координаты как немасштабированные.
+    /// </remarks>
+    private static PopupWindowNative.Rect? Validate(PopupWindowNative.Rect caret, IntPtr hwndFocus)
+    {
+        if (hwndFocus == IntPtr.Zero || !GetWindowRect(hwndFocus, out PopupWindowNative.Rect window))
+        {
+            return caret;
+        }
+
+        if (IsInside(caret, window))
+        {
+            return caret;
+        }
+
+        double scale = GetDpiForWindow(hwndFocus) / 96.0;
+        var scaled = new PopupWindowNative.Rect
+        {
+            Left = (int)(caret.Left * scale),
+            Top = (int)(caret.Top * scale),
+            Right = (int)(caret.Right * scale),
+            Bottom = (int)(caret.Bottom * scale),
+        };
+
+        return IsInside(scaled, window) ? scaled : null;
+    }
+
+    private static bool IsInside(PopupWindowNative.Rect inner, PopupWindowNative.Rect outer) =>
+        inner.Left >= outer.Left && inner.Right <= outer.Right &&
+        inner.Top >= outer.Top && inner.Bottom <= outer.Bottom;
+
     /// <summary>Сколько ждём ответа от чужого приложения по UI Automation.</summary>
     private static readonly TimeSpan AutomationTimeout = TimeSpan.FromMilliseconds(150);
 
@@ -127,7 +147,7 @@ internal static class CaretNative
     }
 
     // Системная каретка: координаты приходят относительно окна, которому она принадлежит
-    private static PopupWindowNative.Rect? TryGetSystemCaret(GuiThreadInfo info)
+    private static PopupWindowNative.Rect? TryGetSystemCaret(ForegroundInputNative.GuiThreadInfo info)
     {
         if (info.hwndCaret == IntPtr.Zero || IsEmpty(info.rcCaret))
         {