swaybar: handle mode/hidden_state changes

As well as adding the hidden_state property to the bar config struct,
this commit handles barconfig_update events when the mode or
hidden_state changes, and uses a new function determine_bar_visibility
to hide or show the bar as required, using, respectively,
destroy_layer_surface, which is also newly added, and add_layer_surface,
which has been changed to allow dynamically adding the surface.

4 files changed, 108 insertions, 11 deletions

diff --git a/swaybar/bar.c b/swaybar/bar.c
index 77294136..6894383d 100644
--- a/swaybar/bar.c
+++ b/swaybar/bar.c
@@ -32,6 +32,7 @@
 
 static void bar_init(struct swaybar *bar) {
         bar->config = init_config();
+        bar->visible = true;
         wl_list_init(&bar->outputs);
 }
 
@@ -338,21 +339,65 @@ const struct wl_seat_listener seat_listener = {
 };
 
 static void add_layer_surface(struct swaybar_output *output) {
-        if (output->surface != NULL) {
+        if (output->layer_surface) {
                 return;
         }
         struct swaybar *bar = output->bar;
 
-        output->surface = wl_compositor_create_surface(bar->compositor);
-        assert(output->surface);
+        struct swaybar_config *config = bar->config;
+        bool hidden = strcmp(config->mode, "hide") == 0;
         output->layer_surface = zwlr_layer_shell_v1_get_layer_surface(
                         bar->layer_shell, output->surface, output->output,
+                        hidden ? ZWLR_LAYER_SHELL_V1_LAYER_TOP :
                         ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM, "panel");
         assert(output->layer_surface);
         zwlr_layer_surface_v1_add_listener(output->layer_surface,
                         &layer_surface_listener, output);
-        zwlr_layer_surface_v1_set_anchor(output->layer_surface,
-                        bar->config->position);
+
+        zwlr_layer_surface_v1_set_anchor(output->layer_surface, config->position);
+        if (hidden) {
+                zwlr_layer_surface_v1_set_exclusive_zone(output->layer_surface, -1);
+        }
+}
+
+static void destroy_layer_surface(struct swaybar_output *output) {
+        if (!output->layer_surface) {
+                return;
+        }
+        zwlr_layer_surface_v1_destroy(output->layer_surface);
+        wl_surface_attach(output->surface, NULL, 0, 0); // detach buffer
+        output->layer_surface = NULL;
+        output->height = 0;
+        output->width = 0;
+        output->frame_scheduled = false;
+}
+
+bool determine_bar_visibility(struct swaybar *bar, bool moving_layer) {
+        struct swaybar_config *config = bar->config;
+        bool visible = !(strcmp(config->mode, "invisible") == 0 ||
+                (strcmp(config->mode, config->hidden_state) == 0 // both "hide"
+                        && !bar->visible_by_modifier && !bar->visible_by_urgency));
+
+        struct swaybar_output *output;
+        if (visible == bar->visible) {
+                if (visible && moving_layer) {
+                        // need to destroy layer surface to move to a different layer
+                        wl_list_for_each(output, &bar->outputs, link) {
+                                destroy_layer_surface(output);
+                                add_layer_surface(output);
+                        }
+                }
+        } else {
+                bar->visible = visible;
+                wl_list_for_each(output, &bar->outputs, link) {
+                        if (visible) {
+                                add_layer_surface(output);
+                        } else {
+                                destroy_layer_surface(output);
+                        }
+                }
+        }
+        return visible;
 }
 
 static bool bar_uses_output(struct swaybar *bar, const char *name) {
@@ -423,8 +468,11 @@ static void xdg_output_handle_done(void *data,
                 wl_list_remove(&output->link);
                 wl_list_insert(&bar->outputs, &output->link);
 
-                add_layer_surface(output);
-                set_output_dirty(output);
+                output->surface = wl_compositor_create_surface(bar->compositor);
+                assert(output->surface);
+                if (bar->visible) {
+                        add_layer_surface(output);
+                }
         }
 }
 
diff --git a/swaybar/config.c b/swaybar/config.c
index 09d40c24..eafb0b69 100644
--- a/swaybar/config.c
+++ b/swaybar/config.c
@@ -30,7 +30,8 @@ struct swaybar_config *init_config(void) {
         config->pango_markup = false;
         config->position = parse_position("bottom");
         config->font = strdup("monospace 10");
-        config->mode = NULL;
+        config->mode = strdup("dock");
+        config->hidden_state = strdup("hide");
         config->sep_symbol = NULL;
         config->strip_workspace_numbers = false;
         config->binding_mode_indicator = true;
@@ -84,6 +85,7 @@ void free_config(struct swaybar_config *config) {
         free(config->status_command);
         free(config->font);
         free(config->mode);
+        free(config->hidden_state);
         free(config->sep_symbol);
         for (int i = 0; i < config->bindings->length; i++) {
                 struct swaybar_binding *binding = config->bindings->items[i];
diff --git a/swaybar/ipc.c b/swaybar/ipc.c
index 6013c2de..56379fdb 100644
--- a/swaybar/ipc.c
+++ b/swaybar/ipc.c
@@ -152,12 +152,12 @@ static bool ipc_parse_config(
                 json_object_put(bar_config);
                 return false;
         }
-        json_object *markup, *mode, *hidden_bar, *position, *status_command;
+        json_object *markup, *mode, *hidden_state, *position, *status_command;
         json_object *font, *bar_height, *wrap_scroll, *workspace_buttons, *strip_workspace_numbers;
         json_object *binding_mode_indicator, *verbose, *colors, *sep_symbol, *outputs;
         json_object *bindings;
         json_object_object_get_ex(bar_config, "mode", &mode);
-        json_object_object_get_ex(bar_config, "hidden_bar", &hidden_bar);
+        json_object_object_get_ex(bar_config, "hidden_state", &hidden_state);
         json_object_object_get_ex(bar_config, "position", &position);
         json_object_object_get_ex(bar_config, "status_command", &status_command);
         json_object_object_get_ex(bar_config, "font", &font);
@@ -220,6 +220,14 @@ static bool ipc_parse_config(
                         list_add(config->bindings, binding);
                 }
         }
+        if (hidden_state) {
+                free(config->hidden_state);
+                config->hidden_state = strdup(json_object_get_string(hidden_state));
+        }
+        if (mode) {
+                free(config->mode);
+                config->mode = strdup(json_object_get_string(mode));
+        }
 
         struct config_output *output, *tmp;
         wl_list_for_each_safe(output, tmp, &config->outputs, link) {
@@ -367,6 +375,37 @@ bool ipc_initialize(struct swaybar *bar) {
         return true;
 }
 
+static bool handle_barconfig_update(struct swaybar *bar,
+                json_object *json_config) {
+        json_object *json_id;
+        json_object_object_get_ex(json_config, "id", &json_id);
+        const char *id = json_object_get_string(json_id);
+        if (strcmp(id, bar->id) != 0) {
+                return false;
+        }
+
+        struct swaybar_config *config = bar->config;
+
+        json_object *json_state;
+        json_object_object_get_ex(json_config, "hidden_state", &json_state);
+        const char *new_state = json_object_get_string(json_state);
+        char *old_state = config->hidden_state;
+        if (strcmp(new_state, old_state) != 0) {
+                wlr_log(WLR_DEBUG, "Changing bar hidden state to %s", new_state);
+                free(old_state);
+                config->hidden_state = strdup(new_state);
+                return determine_bar_visibility(bar, false);
+        }
+
+        free(config->mode);
+        json_object *json_mode;
+        json_object_object_get_ex(json_config, "mode", &json_mode);
+        config->mode = strdup(json_object_get_string(json_mode));
+        wlr_log(WLR_DEBUG, "Changing bar mode to %s", config->mode);
+
+        return determine_bar_visibility(bar, true);
+}
+
 bool handle_ipc_readable(struct swaybar *bar) {
         struct ipc_response *resp = ipc_recv_response(bar->ipc_event_socketfd);
         if (!resp) {
@@ -402,6 +441,9 @@ bool handle_ipc_readable(struct swaybar *bar) {
                 }
                 break;
         }
+        case IPC_EVENT_BARCONFIG_UPDATE:
+                bar_is_dirty = handle_barconfig_update(bar, result);
+                break;
         default:
                 bar_is_dirty = false;
                 break;
diff --git a/swaybar/render.c b/swaybar/render.c
index d226ba32..670630cf 100644
--- a/swaybar/render.c
+++ b/swaybar/render.c
@@ -494,6 +494,9 @@ static const struct wl_callback_listener output_frame_listener = {
 
 void render_frame(struct swaybar_output *output) {
         assert(output->surface != NULL);
+        if (!output->layer_surface) {
+                return;
+        }
 
         free_hotspots(&output->hotspots);
 
@@ -519,7 +522,9 @@ void render_frame(struct swaybar_output *output) {
         if (height != output->height) {
                 // Reconfigure surface
                 zwlr_layer_surface_v1_set_size(output->layer_surface, 0, height);
-                zwlr_layer_surface_v1_set_exclusive_zone(output->layer_surface, height);
+                if (strcmp(output->bar->config->mode, "dock") == 0) {
+                        zwlr_layer_surface_v1_set_exclusive_zone(output->layer_surface, height);
+                }
                 // TODO: this could infinite loop if the compositor assigns us a
                 // different height than what we asked for
                 wl_surface_commit(output->surface);