[mutter/wip/exalm/focused-appearance: 751/752] window: Make default focus window on each workspace appear focused

[Alexander Mikhaylenko <alexm src gnome org>]

commit b81b39c7cddedcf481d798ff46fd6acb070a7616
Author: Alexander Mikhaylenko <exalm7659 gmail com>
Date:   Sat Oct 12 23:55:26 2019 +0500

    window: Make default focus window on each workspace appear focused
    
    Makes workspace transitions in gnome-shell look more seamless, since
    both outgoing and incoming workspace have focused windows.
    
    This is only done for click focus mode, since it's not known which
    window would be focused for the other modes.
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/850

 src/core/window-private.h |  2 ++
 src/core/window.c         | 21 +++++++++++++++++++--
 src/core/workspace.c      | 26 ++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 2 deletions(-)
---
diff --git a/src/core/window-private.h b/src/core/window-private.h
index 0d1ff6831..f316b83c9 100644
--- a/src/core/window-private.h
+++ b/src/core/window-private.h
@@ -704,6 +704,8 @@ void        meta_window_get_session_geometry (MetaWindow  *window,
 
 void        meta_window_update_unfocused_button_grabs (MetaWindow *window);
 
+void        meta_window_appears_focused_changed (MetaWindow *window);
+
 void     meta_window_set_focused_internal (MetaWindow *window,
                                            gboolean    focused);
 
diff --git a/src/core/window.c b/src/core/window.c
index 75012ed6c..3e23d7e85 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -251,6 +251,10 @@ prefs_changed_callback (MetaPreference pref,
       meta_window_recalc_features (window);
       meta_window_queue (window, META_QUEUE_MOVE_RESIZE);
     }
+  else if (pref == META_PREF_FOCUS_MODE)
+    {
+      meta_window_appears_focused_changed (window);
+    }
 }
 
 static void
@@ -4872,6 +4876,9 @@ set_workspace_state (MetaWindow    *window,
         }
     }
 
+  if (!window->constructing)
+    meta_window_appears_focused_changed (window);
+
   /* queue a move_resize since changing workspaces may change
    * the relevant struts
    */
@@ -5171,7 +5178,7 @@ meta_window_change_workspace_by_index (MetaWindow *window,
     meta_window_change_workspace (window, workspace);
 }
 
-static void
+void
 meta_window_appears_focused_changed (MetaWindow *window)
 {
   set_net_wm_state (window);
@@ -7255,7 +7262,17 @@ meta_window_get_frame (MetaWindow *window)
 gboolean
 meta_window_appears_focused (MetaWindow *window)
 {
-  return window->has_focus || (window->attached_focus_window != NULL);
+  MetaWorkspaceManager *workspace_manager;
+  MetaWorkspace *workspace;
+  MetaWindow *default_window = NULL;
+
+  workspace_manager = window->display->workspace_manager;
+  workspace = meta_window_get_workspace (window);
+
+  if (workspace && workspace != workspace_manager->active_workspace)
+    default_window = meta_workspace_get_default_focus_window (workspace);
+
+  return window->has_focus || (window->attached_focus_window != NULL) || (window == default_window);
 }
 
 gboolean
diff --git a/src/core/workspace.c b/src/core/workspace.c
index 4847220a8..cf8e1253a 100644
--- a/src/core/workspace.c
+++ b/src/core/workspace.c
@@ -356,10 +356,27 @@ meta_workspace_remove (MetaWorkspace *workspace)
    */
 }
 
+static void
+workspace_default_focus_changed (MetaWorkspace *workspace,
+                                 MetaWindow    *not_this_one)
+{
+  GSList *windows, *l;
+
+  windows = meta_display_list_windows (workspace->display, META_LIST_DEFAULT);
+  for (l = windows; l; l = l->next) {
+    MetaWindow *window = META_WINDOW (l->data);
+
+    if (meta_window_located_on_workspace (window, workspace) && window != not_this_one)
+      meta_window_appears_focused_changed (window);
+  }
+}
+
 void
 meta_workspace_add_window (MetaWorkspace *workspace,
                            MetaWindow    *window)
 {
+  MetaWorkspaceManager *manager = workspace->display->workspace_manager;
+
   COGL_TRACE_BEGIN_SCOPED (MetaWorkspaceAddWindow,
                            "Workspace (add window)");
 
@@ -376,6 +393,9 @@ meta_workspace_add_window (MetaWorkspace *workspace,
       meta_workspace_invalidate_work_area (workspace);
     }
 
+  if (workspace != manager->active_workspace)
+    workspace_default_focus_changed (workspace, window);
+
   g_signal_emit (workspace, signals[WINDOW_ADDED], 0, window);
   g_object_notify_by_pspec (G_OBJECT (workspace), obj_props[PROP_N_WINDOWS]);
 }
@@ -384,6 +404,8 @@ void
 meta_workspace_remove_window (MetaWorkspace *workspace,
                               MetaWindow    *window)
 {
+  MetaWorkspaceManager *manager = workspace->display->workspace_manager;
+
   COGL_TRACE_BEGIN_SCOPED (MetaWorkspaceRemoveWindow,
                            "Workspace (remove window)");
 
@@ -400,6 +422,9 @@ meta_workspace_remove_window (MetaWorkspace *workspace,
       meta_workspace_invalidate_work_area (workspace);
     }
 
+  if (workspace != manager->active_workspace)
+    workspace_default_focus_changed (workspace, window);
+
   g_signal_emit (workspace, signals[WINDOW_REMOVED], 0, window);
   g_object_notify (G_OBJECT (workspace), "n-windows");
 }
@@ -644,6 +669,7 @@ meta_workspace_activate_with_focus (MetaWorkspace *workspace,
   if (focus_this)
     {
       meta_window_activate (focus_this, timestamp);
+      workspace_default_focus_changed (workspace, focus_this);
     }
   else if (move_window)
     {