feat(display) output status widget shows ble information when preferred

Shows the active ble connnection when it is the preferred connection
this allows unbonded and inactive connections to be toggled through
even if the keyboard has an active connection of another transport type.

Changes TRANSPORT_NONE symbol to minus so it is different to the
inactive ble connection icon

Author: yrb

app/src/display/widgets/output_status.c

@@ -14,15 +14,22 @@ LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
 #include <zmk/event_manager.h>
 #include <zmk/events/ble_active_profile_changed.h>
 #include <zmk/events/endpoint_changed.h>
+#include <zmk/events/preferred_transport_changed.h>
 #include <zmk/usb.h>
 #include <zmk/ble.h>
 #include <zmk/endpoints.h>
 
+static const char TRANSPORT_SYMBOL_NONE[] = LV_SYMBOL_CLOSE;
+static const char TRANSPORT_SYMBOL_BLE[] = LV_SYMBOL_WIFI;
+static const char TRANSPORT_SYMBOL_USB[] = LV_SYMBOL_USB;
+static const char TRANSPORT_SYMBOL_UNKNOWN[] = "?";
+
 static sys_slist_t widgets = SYS_SLIST_STATIC_INIT(&widgets);
 
 struct output_status_state {
     struct zmk_endpoint_instance selected_endpoint;
     enum zmk_transport preferred_transport;
+    int active_profile_index;
     bool active_profile_connected;
     bool active_profile_bonded;
 };
@@ -31,48 +38,67 @@ static struct output_status_state get_state(const zmk_event_t *_eh) {
     return (struct output_status_state){
         .selected_endpoint = zmk_endpoint_get_selected(),
         .preferred_transport = zmk_endpoint_get_preferred_transport(),
+        .active_profile_index = zmk_ble_active_profile_index(),
         .active_profile_connected = zmk_ble_active_profile_is_connected(),
         .active_profile_bonded = !zmk_ble_active_profile_is_open(),
     };
 }
 
+static const char *symbol_for_transport(enum zmk_transport transport) {
+    switch (transport) {
+    case ZMK_TRANSPORT_NONE:
+        return TRANSPORT_SYMBOL_NONE;
+    case ZMK_TRANSPORT_BLE:
+        return TRANSPORT_SYMBOL_BLE;
+    case ZMK_TRANSPORT_USB:
+        return TRANSPORT_SYMBOL_USB;
+    default:
+        return TRANSPORT_SYMBOL_UNKNOWN;
+    }
+}
+
 static void set_status_symbol(lv_obj_t *label, struct output_status_state state) {
     char text[20] = {};
 
     enum zmk_transport transport = state.selected_endpoint.transport;
-    bool connected = transport != ZMK_TRANSPORT_NONE;
+    const char *transport_symbol = symbol_for_transport(transport);
 
-    // If we aren't connected, show what we're *trying* to connect to.
-    if (!connected) {
-        transport = state.preferred_transport;
-    }
-
-    switch (transport) {
-    case ZMK_TRANSPORT_NONE:
-        strcat(text, LV_SYMBOL_CLOSE);
-        break;
+    bool connected = transport != ZMK_TRANSPORT_NONE;
 
-    case ZMK_TRANSPORT_USB:
-        strcat(text, LV_SYMBOL_USB);
-        if (!connected) {
-            strcat(text, " " LV_SYMBOL_CLOSE);
+    // If we are ble is connected or the preferred_transport show the active profile status
+    // This allows you to navigate through the active ble profiles, even when they are unable
+    // to be connected to.
+    if (transport == ZMK_TRANSPORT_BLE || state.preferred_transport == ZMK_TRANSPORT_BLE) {
+        const char *active_profile_status = "?";
+
+        // When the preferred transport if ble but it is disconneted, the state is represented
+        // by the active_profile_status, just display the ble symbol. This is like this
+        // so it will display the active transport (eg. usb) when we are connected to it
+        // but still keep displaying the ble profile.
+        if (transport == ZMK_TRANSPORT_NONE) {
+            transport_symbol = TRANSPORT_SYMBOL_BLE;
         }
-        break;
 
-    case ZMK_TRANSPORT_BLE:
         if (state.active_profile_bonded) {
             if (state.active_profile_connected) {
-                snprintf(text, sizeof(text), LV_SYMBOL_WIFI " %i " LV_SYMBOL_OK,
-                         state.selected_endpoint.ble.profile_index + 1);
+                active_profile_status = LV_SYMBOL_OK;
             } else {
-                snprintf(text, sizeof(text), LV_SYMBOL_WIFI " %i " LV_SYMBOL_CLOSE,
-                         state.selected_endpoint.ble.profile_index + 1);
+                active_profile_status = LV_SYMBOL_CLOSE;
             }
         } else {
-            snprintf(text, sizeof(text), LV_SYMBOL_WIFI " %i " LV_SYMBOL_SETTINGS,
-                     state.selected_endpoint.ble.profile_index + 1);
+            active_profile_status = LV_SYMBOL_SETTINGS;
         }
-        break;
+
+        snprintf(text, sizeof(text), "%s %i %s", transport_symbol, state.active_profile_index + 1,
+                 active_profile_status);
+
+    } else if (!connected && state.preferred_transport != ZMK_TRANSPORT_NONE) {
+        // When we are not connected but have a preferred transport
+        // indicate that we are disconnected from it.
+        snprintf(text, sizeof(text), "%s " LV_SYMBOL_CLOSE,
+                 symbol_for_transport(state.preferred_transport));
+    } else {
+        strcat(text, transport_symbol);
     }
 
     lv_label_set_text(label, text);
@@ -86,6 +112,7 @@ static void output_status_update_cb(struct output_status_state state) {
 ZMK_DISPLAY_WIDGET_LISTENER(widget_output_status, struct output_status_state,
                             output_status_update_cb, get_state)
 ZMK_SUBSCRIPTION(widget_output_status, zmk_endpoint_changed);
+ZMK_SUBSCRIPTION(widget_output_status, zmk_preferred_transport_changed);
 // We don't get an endpoint changed event when the active profile connects/disconnects
 // but there wasn't another endpoint to switch from/to, so update on BLE events too.
 #if defined(CONFIG_ZMK_BLE)