wind: Stop tracking windows after they're closed

wind/IPC.cpp

@@ -1,4 +1,5 @@
 #include "IPC.h"
+#include "Mouse.h"
 #include "Screen.h"
 #include <luna/Alignment.h>
 #include <luna/String.h>
@@ -129,6 +130,7 @@ static Result<void> handle_close_window_message(Client& client)
     auto* window = client.windows[request.window];
     client.windows[request.window] = nullptr;
     g_windows.remove(window);
+    Mouse::the().window_did_close(window);
     delete window;
 
     return {};

wind/Mouse.cpp

@@ -7,6 +7,8 @@
 
 static SharedPtr<ui::Image> g_mouse_cursor;
 
+static Mouse* s_mouse;
+
 Mouse::Mouse(ui::Canvas& screen)
 {
     m_position.x = screen.width / 2;
@@ -14,6 +16,14 @@ Mouse::Mouse(ui::Canvas& screen)
     m_screen_rect = screen.rect();
 
     g_mouse_cursor = ui::Image::load("/usr/share/cursors/default.tga").value_or({});
+
+    s_mouse = this;
+}
+
+Mouse& Mouse::the()
+{
+    check(s_mouse);
+    return *s_mouse;
 }
 
 void Mouse::draw(ui::Canvas& screen)
@@ -110,3 +120,10 @@ void Mouse::update(const moon::MousePacket& packet)
         m_active_window = new_active_window;
     }
 }
+
+void Mouse::window_did_close(Window* window)
+{
+    if (m_dragging_window == window) { m_dragging_window = nullptr; }
+
+    if (m_active_window == window) { m_active_window = nullptr; }
+}

wind/Mouse.h

@@ -13,6 +13,10 @@ class Mouse
 
     void draw(ui::Canvas& screen);
 
+    void window_did_close(Window* window);
+
+    static Mouse& the();
+
   private:
     ui::Point m_position;
     ui::Rect m_screen_rect;

wind/main.cpp

@@ -179,6 +179,7 @@ Result<int> luna_main(int argc, char** argv)
                     if (window)
                     {
                         g_windows.remove(window);
+                        mouse_pointer.window_did_close(window);
                         delete window;
                     }
                 }