[gtk+/wip/gbsneto/edge-constraints-gtk4: 2/6] window: handle tiled edges separately

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 84448ce96a1af3cc30c766ff11272cd48f75a597
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Thu Aug 17 00:30:31 2017 -0300

    window: handle tiled edges separately
    
    GTK windows don't have their tiling states really
    hooked into the client-side decoration code, and
    the only effect it has is disabling the resizing
    edges.
    
    With the introduction of per-edge tiling information,
    we are backed by much more precise data on how the
    window manager wants the app to behave.
    
    This patch, then, fixes GtkWindow to take into account
    per-edge tiling information. For compatibility purposes,
    the previous tiled field was kept, and thing will just
    continue working if no edge information is supplied.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=783669

 gtk/gtkwindow.c |   44 +++++++++++++++++++++++++++++++++++++-------
 1 files changed, 37 insertions(+), 7 deletions(-)
---
diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index 2e8f5b4..d2af718 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -215,6 +215,7 @@ struct _GtkWindowPrivate
   GtkWidget *popup_menu;
 
   gint       initial_fullscreen_monitor;
+  guint      edge_constraints;
 
   /* The following flags are initially TRUE (before a window is mapped).
    * They cause us to compute a configure request that involves
@@ -1702,11 +1703,13 @@ edge_under_coordinates (GtkWindow     *window,
   if (priv->type != GTK_WINDOW_TOPLEVEL ||
       !priv->client_decorated ||
       !priv->resizable ||
-      priv->tiled ||
       priv->fullscreen ||
       priv->maximized)
     return FALSE;
 
+  if (priv->tiled && !priv->edge_constraints)
+    return FALSE;
+
   _gtk_widget_get_allocation (GTK_WIDGET (window), &allocation);
   context = _gtk_widget_get_style_context (GTK_WIDGET (window));
   gtk_style_context_save_to_node (context, priv->decoration_node);
@@ -1740,6 +1743,9 @@ edge_under_coordinates (GtkWindow     *window,
           edge != GDK_WINDOW_EDGE_WEST &&
           edge != GDK_WINDOW_EDGE_SOUTH_WEST)
         return FALSE;
+
+      if (!(priv->edge_constraints & GDK_WINDOW_STATE_LEFT_RESIZABLE))
+        return FALSE;
     }
   else if (x >= allocation.x + allocation.width - border.right - handle_h)
     {
@@ -1747,6 +1753,9 @@ edge_under_coordinates (GtkWindow     *window,
           edge != GDK_WINDOW_EDGE_EAST &&
           edge != GDK_WINDOW_EDGE_SOUTH_EAST)
         return FALSE;
+
+      if (!(priv->edge_constraints & GDK_WINDOW_STATE_RIGHT_RESIZABLE))
+        return FALSE;
     }
   else if (edge != GDK_WINDOW_EDGE_NORTH &&
            edge != GDK_WINDOW_EDGE_SOUTH)
@@ -1759,6 +1768,9 @@ edge_under_coordinates (GtkWindow     *window,
           edge != GDK_WINDOW_EDGE_NORTH &&
           edge != GDK_WINDOW_EDGE_NORTH_EAST)
         return FALSE;
+
+      if (!(priv->edge_constraints & GDK_WINDOW_STATE_TOP_RESIZABLE))
+        return FALSE;
     }
   else if (y > allocation.y + allocation.height - border.bottom - handle_v)
     {
@@ -1766,6 +1778,9 @@ edge_under_coordinates (GtkWindow     *window,
           edge != GDK_WINDOW_EDGE_SOUTH &&
           edge != GDK_WINDOW_EDGE_SOUTH_EAST)
         return FALSE;
+
+      if (!(priv->edge_constraints & GDK_WINDOW_STATE_BOTTOM_RESIZABLE))
+        return FALSE;
     }
   else if (edge != GDK_WINDOW_EDGE_WEST &&
            edge != GDK_WINDOW_EDGE_EAST)
@@ -7132,6 +7147,25 @@ gtk_window_configure_event (GtkWidget         *widget,
   return TRUE;
 }
 
+static void
+update_edge_constraints (GtkWindow           *window,
+                         GdkEventWindowState *event)
+{
+  GtkWindowPrivate *priv = window->priv;
+  GdkWindowState state = event->new_window_state;
+
+  priv->edge_constraints = (state & GDK_WINDOW_STATE_TOP_TILED) |
+                           (state & GDK_WINDOW_STATE_TOP_RESIZABLE) |
+                           (state & GDK_WINDOW_STATE_RIGHT_TILED) |
+                           (state & GDK_WINDOW_STATE_RIGHT_RESIZABLE) |
+                           (state & GDK_WINDOW_STATE_BOTTOM_TILED) |
+                           (state & GDK_WINDOW_STATE_BOTTOM_RESIZABLE) |
+                           (state & GDK_WINDOW_STATE_LEFT_TILED) |
+                           (state & GDK_WINDOW_STATE_LEFT_RESIZABLE);
+
+  priv->tiled = (state & GDK_WINDOW_STATE_TILED) ? 1 : 0;
+}
+
 static gboolean
 gtk_window_state_event (GtkWidget           *widget,
                         GdkEventWindowState *event)
@@ -7148,12 +7182,6 @@ gtk_window_state_event (GtkWidget           *widget,
         (event->new_window_state & GDK_WINDOW_STATE_FULLSCREEN) ? 1 : 0;
     }
 
-  if (event->changed_mask & GDK_WINDOW_STATE_TILED)
-    {
-      priv->tiled =
-        (event->new_window_state & GDK_WINDOW_STATE_TILED) ? 1 : 0;
-    }
-
   if (event->changed_mask & GDK_WINDOW_STATE_MAXIMIZED)
     {
       priv->maximized =
@@ -7161,6 +7189,8 @@ gtk_window_state_event (GtkWidget           *widget,
       g_object_notify_by_pspec (G_OBJECT (widget), window_props[PROP_IS_MAXIMIZED]);
     }
 
+  update_edge_constraints (window, event);
+
   if (event->changed_mask & (GDK_WINDOW_STATE_FULLSCREEN | GDK_WINDOW_STATE_MAXIMIZED | 
GDK_WINDOW_STATE_TILED))
     {
       update_window_style_classes (window);