lightweight variant (#1)

Reviewed-on: #1
Co-authored-by: Aleksandr Neychev <alexnejchev73@gmail.com>

CursorLang.Core/Services/ILayoutPopupWindow.cs

@@ -0,0 +1,28 @@
+namespace CursorLang.Core.Services;
+
+/// <summary>
+/// The popup window as seen by whoever decides when it is shown.
+/// </summary>
+/// <remarks>
+/// The window picks its place and size itself, and only three actions are needed from
+/// it on the outside. The tests check the work of the popup service through the same
+/// interface: there is no point bringing up a real window to check a timer.
+/// </remarks>
+public interface ILayoutPopupWindow
+{
+    /// <summary>
+    /// Shows the window with the given text at the place set by the settings.
+    /// </summary>
+    /// <remarks>
+    /// The text is passed in rather than bound: there is no view model behind the
+    /// window any more, and no data binding either — it is a Win32 window that paints
+    /// one line of text itself.
+    /// </remarks>
+    void ShowPopup(string shortName);
+
+    /// <summary>Takes the window off the screen without destroying it.</summary>
+    void Hide();
+
+    /// <summary>Closes the window for good.</summary>
+    void Close();
+}