Implement focus handling for containers

The previous implementation of focus handling assumed that only views can be
focused. Containers can also be focused with a command like `focus parent` or
`focus child`.

Change `set_focused_container()` to handle the case of the given container
being a container with children and update borders accordingly.

3 files changed, 36 insertions, 18 deletions

diff --git a/include/border.h b/include/border.h
index b629ba46..b61b0f8a 100644
--- a/include/border.h
+++ b/include/border.h
@@ -16,6 +16,11 @@ struct border {
  */
 void border_clear(struct border *border);
 
+/**
+ * Recursively update all of the borders within a container.
+ */
+void update_container_border(swayc_t *container);
+
 void render_view_borders(wlc_handle view);
 void update_view_border(swayc_t *view);
 void map_update_view_border(swayc_t *view, void *data);
diff --git a/sway/border.c b/sway/border.c
index c1a62bc6..c3e1004a 100644
--- a/sway/border.c
+++ b/sway/border.c
@@ -308,6 +308,9 @@ void update_view_border(swayc_t *view) {
         swayc_t *focused = get_focused_view(&root_container);
         swayc_t *container = swayc_parent_by_type(view, C_CONTAINER);
         swayc_t *focused_inactive = NULL;
+
+        bool is_child_of_focused = swayc_is_parent_of(get_focused_container(&root_container), view);
+
         if (container) {
                 focused_inactive = swayc_focus_by_type(container, C_VIEW);
         } else {
@@ -334,7 +337,7 @@ void update_view_border(swayc_t *view) {
                 cr = create_border_buffer(view, g, &surface);
 
                 bool render_top = !should_hide_top_border(view, view->y);
-                if (view == focused) {
+                if (view == focused || is_child_of_focused) {
                         render_borders(view, cr, &config->border_colors.focused, render_top);
                 } else {
                         render_borders(view, cr, &config->border_colors.focused_inactive, render_top);
@@ -360,7 +363,7 @@ void update_view_border(swayc_t *view) {
                                 break;
                         }
 
-                        if (focused == view) {
+                        if (focused == view || is_child_of_focused) {
                                 render_borders(view, cr, &config->border_colors.focused, true);
                         } else if (focused_inactive == view) {
                                 render_borders(view, cr, &config->border_colors.focused_inactive, true);
@@ -375,7 +378,7 @@ void update_view_border(swayc_t *view) {
                                 break;
                         }
 
-                        if (focused == view) {
+                        if (focused == view || is_child_of_focused) {
                                 render_borders(view, cr, &config->border_colors.focused, false);
                                 render_title_bar(view, cr, &view->border_geometry,
                                         &config->border_colors.focused);
@@ -403,6 +406,17 @@ void update_view_border(swayc_t *view) {
         }
 }
 
+void update_container_border(swayc_t *container) {
+        if (container->type == C_VIEW) {
+                update_view_border(container);
+                return;
+        } else {
+                for (int i = 0; i < container->children->length; ++i) {
+                        update_container_border(container->children->items[i]);
+                }
+        }
+}
+
 void render_view_borders(wlc_handle view) {
         swayc_t *c = swayc_by_handle(view);
 
diff --git a/sway/focus.c b/sway/focus.c
index 0f629e1e..576a5e9b 100644
--- a/sway/focus.c
+++ b/sway/focus.c
@@ -115,7 +115,7 @@ bool set_focused_container(swayc_t *c) {
 
         // Get workspace for c, get that workspaces current focused container.
         swayc_t *workspace = swayc_active_workspace_for(c);
-        swayc_t *focused = get_focused_view(workspace);
+        swayc_t *focused = get_focused_container(workspace);
 
         if (swayc_is_fullscreen(focused) && focused != c) {
                 // if switching to a workspace with a fullscreen view,
@@ -140,33 +140,32 @@ bool set_focused_container(swayc_t *c) {
         }
 
         // get new focused view and set focus to it.
-        p = get_focused_view(c);
-        if (p->type == C_VIEW && !(wlc_view_get_type(p->handle) & WLC_BIT_POPUP)) {
+        if (c->type == C_CONTAINER || (c->type == C_VIEW && !(wlc_view_get_type(p->handle) & WLC_BIT_POPUP))) {
                 // unactivate previous focus
                 if (focused->type == C_VIEW) {
                         wlc_view_set_state(focused->handle, WLC_BIT_ACTIVATED, false);
-                        update_view_border(focused);
                 }
+                update_container_border(focused);
                 // activate current focus
-                if (p->type == C_VIEW) {
-                        wlc_view_set_state(p->handle, WLC_BIT_ACTIVATED, true);
-                        // set focus if view_focus is unlocked
-                        if (!locked_view_focus) {
-                                wlc_view_focus(p->handle);
-                                if (p->parent->layout != L_TABBED
-                                        && p->parent->layout != L_STACKED) {
-                                        update_view_border(p);
-                                }
+                if (c->type == C_VIEW) {
+                        wlc_view_set_state(c->handle, WLC_BIT_ACTIVATED, true);
+                }
+                // set focus if view_focus is unlocked
+                if (!locked_view_focus) {
+                        wlc_view_focus(c->handle);
+                        if (c->parent->layout != L_TABBED
+                                        && c->parent->layout != L_STACKED) {
+                                update_container_border(c);
                         }
                 }
 
                 // rearrange if parent container is tabbed/stacked
-                swayc_t *parent = swayc_tabbed_stacked_ancestor(p);
+                swayc_t *parent = swayc_tabbed_stacked_ancestor(c);
                 if (parent != NULL) {
                         arrange_backgrounds();
                         arrange_windows(parent, -1, -1);
                 }
-        } else if (p->type == C_WORKSPACE) {
+        } else if (c->type == C_WORKSPACE) {
                 // remove previous focus if view_focus is unlocked
                 if (!locked_view_focus) {
                         wlc_view_focus(0);